Article Forest Land Quality Evaluation and the Protection Zoning of Subtropical Humid Evergreen Broadleaf Forest Region Based on the PSO-TOPSIS Model and the Local Indicator of Spatial Association: A Case Study of Hefeng County, Province, China

Li Wang 1,2,3 , Yong Zhou 1,2,3,*, Qing Li 1,2,3 , Qian Zuo 1,2,3 , Haoran Gao 1,2,3, Jingyi Liu 1,2,3 and Yang Tian 1,2,3

1 The College of Urban & Environmental Sciences, Central China Normal University, 430079, China; [email protected] (L.W.); [email protected] (Q.L.); [email protected] (Q.Z.); [email protected] (H.G.); [email protected] (J.L.); [email protected] (Y.T.) 2 Key Laboratory for Geographical Process Analysis & Simulation in Hubei Province, Central China Normal University, Wuhan 430079, China 3 Land Science Research Center, Central China Normal University, Wuhan 430079, China * Correspondence: [email protected]; Tel.: +86-027-67867020

Abstract: Forest land is the carrier for growing forests. It is of great significance to evaluate the forest land quality scientifically and delineate forestland protection zones reasonably for realizing   better forest land management, promoting ecological civilization construction, and coping with global climate change. In this study, taking Hefeng County, Hubei Province, a subtropical humid Citation: Wang, L.; Zhou, Y.; Li, Q.; Zuo, Q.; Gao, H.; Liu, J.; Tian, Y. evergreen broad-leaved forest region in China, as the study area, 14 indicators were selected from four Forest Land Quality Evaluation and dimensions—climatic conditions, terrain, soil conditions, and socioeconomics—to construct a forest the Protection Zoning of Subtropical land quality evaluation index system. Based on the Technique for Order Preference by Similarity to Humid Evergreen Broadleaf Forest Ideal Solution (TOPSIS) model, we introduced the Particle Swarm Optimization (PSO) algorithm to Region Based on the PSO-TOPSIS design the evaluation model to evaluate the forest land quality and analyze the distribution of forest Model and the Local Indicator of land quality in Hefeng. Further, we used the Local Indicator of Spatial Association (LISA) to explore Spatial Association: A Case Study of the spatial distribution of forest land quality and delineate the forest land protection zones. The Hefeng County, Hubei Province, results showed the following: (1) the overall quality of forest land was high, with some variability China. Forests 2021, 12, 325. between regions. The range of Forest Land Quality Index (FLQI) in Hefeng was 0.4091–0.8601, with a https://doi.org/10.3390/f12030325 mean value of 0.6337. The forest land quality grades were mainly first and second grade, with the higher-grade forest land mainly distributed in the central and southeastern low mountain regions of Received: 23 January 2021 Zouma, Wuli, and Yanzi. The lower-grade forest land was mainly distributed in the northwestern Accepted: 9 March 2021 Published: 11 March 2021 middle and high mountain regions of Zhongying, Taiping, and Rongmei. (2) The global spatial autocorrelation index of forest land quality in Hefeng County was 0.7562, indicating that the forest

Publisher’s Note: MDPI stays neutral land quality in the county had a strong spatial similarity. The spatial distribution of similarity types with regard to jurisdictional claims in high-high (HH) and low-low (LL) was more clustered, while the spatial distribution of dissimilarity published maps and institutional affil- types high-low (HL) and low-high (LH) was generally dispersed. (3) Based on the LISA of forest land iations. quality, forest land protection zones were divided into three types: key protection zones (KPZs), active protection zones (APZs), and general protection zones (GPZs). The forest land protection zoning basically coincided with the forest land quality. Combining the characteristics of self-correlated types in different forestland protection zones, corresponding management and protection measures Copyright: © 2021 by the authors. were proposed. This showed that the PSO-TOPSIS model can be effectively used for forest land Licensee MDPI, Basel, Switzerland. quality evaluation. At the same time, the spatial attributes of forest land were incorporated into This article is an open access article the development of forest land protection zoning scheme, which expands the method of forest land distributed under the terms and protection zoning, and can provide a scientific basis and methodological reference for the reasonable conditions of the Creative Commons formulation of forest land use planning in Hefeng County, while also serving as a reference for similar Attribution (CC BY) license (https:// regions and countries. creativecommons.org/licenses/by/ 4.0/).

Forests 2021, 12, 325. https://doi.org/10.3390/f12030325 https://www.mdpi.com/journal/forests Forests 2021, 12, 325 2 of 25

Keywords: forest land quality; protection zoning; PSO-TOPSIS model; LISA; Hefeng County

1. Introduction Forest land is the carrier on which forests grow, with which they form an important terrestrial ecological barrier, accounting for 30% of the Earth’s surface land area and ap- proximate 4 billion ha, and is an important natural resource for sustaining human survival and social development [1–3]. In addition to a variety of ecological services such as water connotation, soil and water conservation, air purification, and carbon storage, forest land is also a main raw material for manufacturing industries and has an important ecological and economic benefit [4–7]. About 25% of the global population depends on forests for food and work [8]. In addition, forest land is also home to nearly 80% of the world’s terrestrial species, and such a rich diversity of species makes them important in maintaining a global ecosystem balance and responding to global environmental change [9]. To emphasize the importance of forest land, the United Nations General Assembly considered the adoption of the United Nations Strategic Plan for Forests (2017–2030) in 2017, which proposes a global action plan for each country to manage various forests land resources sustainably and to improve forest land quality effectively [10]. China is a vast country with a complex and diverse terrain. The high latitudinal difference between the north and south boundaries and the high western and low eastern terrain have created a rich and diverse climate type and physical geography in China, thus nurturing forest land resources with a wide variety of biological species and vegetation types. According to the report on the 9th Inventory of China’s Forest Resources (2014– 2018) [11], China has a forest land area of 324 million ha, a forest cover of 22.96%, a forest stock of 17.56 billion m3, a total forest vegetation biomass of 18.80 billion tons, and a carbon stock of 9.19 billion tons. Although the total area of forest land in China is among the highest in the world, the per capita area of forest land is only 0.61 ha, which is less than 1/3 of the per capita area of forest land in the world [12]. In addition, since China’s reform and opening up in 1978, with the rapid socioeconomic development and population increase in China, much forest land has been transformed into arable land and construction land, resulting in a drastic decrease in forest land area. To strengthen the protection of forest land and improve the efficiency of forest land utilization, China’s State Council adopted the Outline of National Forest Land Protection and Utilization Plan (2010–2020) in 2010, which emphasized the importance of forest land in maintaining the ecological environment, promoting the ecological civilization construction and addressing global climate change [13]. As a result, the area of forest land in China has increased in the last 10 years with reference to the China Forest Resources Report (2014–2018) [11]. With the rapid socioeconomic development, the demand for forest land resources is increasing and the damage to forest land is becoming increasingly severe, causing a decline in the forest land quality. Additionally, climate change and forest fires are also important factors that cause damage to forest land resources resulting in a decline in forest land quality [14,15]. Since the 21st century, under the influence of the global greenhouse effect, continued climate warming has led to a significant increase in the frequency of forest fires and fire area [16,17]. China is a country with large forest land resources, which also is one of the countries with the highest risk of forest fires. Based on the China Forest Fire Protection Industry Current Research and Future Development Trend Analysis Report (2020–2026), in the past 10 years, the area of forest fires in China reached 225,625 ha [18], accounting for 0.07% of the total forest area in China [11], mainly in the northeast and southwest forest areas [19], which not only causes substantial losses to the society and economy, but also results in the degradation of the forest land ecological environment, which directly threatens the sustainable development of forestry and national ecological security [20]. In addition, climate change affects forest soil carbon and nitrogen cycling processes, mainly in terms of its effects on forest land soil respiration, soil carbon and nitrogen pools, and soil Forests 2021, 12, 325 3 of 25

methane and nitrous oxide emissions, thus affecting forest land soil quality [21]. It is thus clear that there is a coupling between forest land degradation and global climate change, and effectively addressing forest land degradation is the key to cope with global climate change. Therefore, a comprehensive understanding of forest land quality, curbing land degradation, and enhancing forest land quality plays a vital role in improving climate change and ensuring national ecological security. Forest land quality is a reflection of the state and condition of the land [22]. Forest land quality is a combination of multiple qualities and is influenced by the type of forest land and its combined characteristics [23]. Therefore, forest land quality evaluation should be based on terrain, soil, and other natural environmental factors closely related to the growth of forest vegetation and relevant management conditions to evaluate forest land quality comprehensively [24]. Scholars have often used terrain, climate, and soil fertility as the major indicators to assess the quality of forest land in the past [25]. Bonilla-Bedoya et al. [26] studied the effect of land-use change on the physicochemical quality of forest soils in the Western Amazonian landscape. Lu F.Z. et al. [27] selected terrain and soil fertility indicators and used the integrated index model to assess the quality of forest land. Wang Y.F. et al. [28] used Delphi to select indicators from soil fertility and wood biomass, which were used to construct a forest land quality evaluation indicator system. With the development of the social economy, people’s understanding of forest land quality has changed, and the evaluation of forest land quality should not merely consider soil fertility, but also land productive potential, land suitability, and ecological safety [29]. At the same time, the selection of indicators differs with different evaluation purposes. In the term of assessment of forest land productive potential, soil physicochemical indicators are mainly selected to reflect basic soil fertility, soil environment, and soil health [30]. When evaluating forest land suitability, climate and terrain factors will be used to select suitable tree species in addition to soil fertility factors that directly affect the productivity of forest land [31]. Additionally, the intensive application of computer technology and “3S” technology, which refers to global positioning systems (GPS), remote sensing (RS), and geographic information systems (GIS), has led to the development of more methods for farmland quality, ranging from simple qualitative description to quantitative analysis. Currently, the main methods commonly used for forest land quality evaluation are entropy weight (EW) [32], fuzzy assessment [33], the analytic hierarchy process (AHP) [34], and gray correlation analysis [35]. These methods all have the characteristics of simple models, strong data compatibility, and wide application. The EW objectively assigns weights based on the physical characteristics of the data, but does not introduce human cognitive discriminations of evaluation indicators [36]. The fuzzy assessment and gray correlation analysis are less stable in dealing with high-dimensional data, and it is difficult to dig deeper into nonlinear information [37,38]. The AHP is more subjective and less sensitive in determining index weights [39]. In recent years, many new algorithms have emerged to integrate different methods to achieve a combination of advantages, reduce the limitations of data analysis on evaluation methods, and improve the objectivity of evaluation results. Among them, the Particle Swarm Optimization (PSO) algorithm and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) algorithm have been used in many aspects such as risk decision analysis, land suitability evaluation, and land ecological safety evaluation [40–43] and have achieved good results. Han G.Y. et al. [44] combined the PSO algorithm and the TOPSIS model to construct an improved TOPSIS model based on the weight of the PSO for the corporate collaborative innovation partner selection model. Ali Bagherzadeh [45] evaluated the suitability of arable land for irrigated alfalfa production in the Joveyn plain of Northeastern Iran using a parameter-based neural network and TOPSIS model. Chen M. et al. [46] applied the EW and TOPSIS model to dynamically evaluate the sustainable land use level in Chengdu of China. Forest land is a special type of land use, and the quality of forest land is affected by the combination of various influencing factors, not in a purely linear relationship, while PSO and TOPSIS are suitable for the processing of nonlinear information problems Forests 2021, 12, 325 4 of 25

with a multifactor influence [44]. Therefore, it is feasible to combine the PSO algorithm and the TOPSIS model for forest land quality evaluation. Nilsson H. et al. [47] studied participatory forest planning in the municipality of Vilhelmina in Northern Sweden, where AHP was used to set weights for objectives based on stakeholder preferences and TOPSIS was used to generate an overall ranking of alternatives. Cai X.T. et al. [48] used the improved TOPSIS model, the hierarchical dynamic attitude model, the Markov chain model, GIS spatial analysis technology, and the barrier degree model to analyze the spatial and temporal patterns, and barrier factors, of forest ecological security in China during 2005–2015. Among a variety of optimization algorithms, the PSO has the unique advantage of a fast computational speed and better global search capability for solving large-scale mathematical optimization problems through memory and feedback mechanisms, with faster convergence than evolutionary algorithms and genetic algorithms, simple parameter settings, a strong local search capability, and a lower likelihood of falling into a local optimum [41]. Zhang Z.D. et al. [49] combined the subjective and objective weights obtained from the PSOAHP model and rough set theory to obtain the combined weights based on the linear weighting idea and evaluated the irrigation water use efficiency of agricultural land using the fuzzy comprehensive evaluation model. At present, the evaluation of forest land quality mainly revolves around the evaluation content, indicator system, and evaluation methods that have been intensively explored, which has enriched the system of forest land quality evaluation; however, there is a lack of study on the differential characteristics of forest land quality in spatial distribution. Hinsley S.A. et al. [50] used airborne laser scanning to study the distribution of forest land structure and bird habitat quality. Ford M.M. et al. [51] assessed the potential of forest rangelands in Minnesota and their spatial distribution by comparing the yields of unmanaged forest land grazing, forest rangeland, and open range systems. Fu X. et al. [52] integrated multitree species to study the spatial distribution of forest land quality and production potential in forest areas. Xing S.H. and Wei H. [53] conducted a zoning study of regional forest land productivity with the help of a dynamic cluster analysis model. In general, the current studies on the spatial characterization of forest land quality tend to describe qualitatively, lacking quantitative analysis, and fail to fully consider the impact of spatial attribute characteristics of forest land quality on forest land conservation. As a spatial entity, the quality of forest land is necessarily influenced by spatial factors, in addition to its natural properties and socioeconomics, and thus has certain spatial distribution characteristics [54]. The delineation of previous forest land protection zones mainly focuses on differences in forest land quality [22,53], ignoring the spatial characteristics of forest land. In addition, forest land protection zoning is a systematic project, and its delineation is not only the result of quality ranking, but also a process of spatial positioning and boundary dropping. Therefore, spatial factors need to be considered in the delineation of forest land protection zones. Subtropical broadleaf evergreen forest is a forest vegetation type with broadleaf ev- ergreen trees as the dominant species growing in a warm and humid subtropical climate. The subtropical broadleaf evergreen forests in China are an important part of the world’s broadleaf evergreen forests and play an important role in maintaining global ecological bal- ance and sustainable human development [55]. As a mountainous region, Hefeng County in Hubei Province of China is an important ecological function reserve in China’s subtropi- cal humid evergreen broad-leaved forest region, with forest land accounting for 88.70% of the county’s total land area. In this study, taking Hefeng County as the study area, we selected 14 indicators including average annual temperature, average annual precipitation, ≥10 ◦C accumulated temperature, wetness index, elevation, slope, soil organic matter, soil layer thickness, soil type, soil texture, soil pH, land degradation, traffic location, and forest disaster grade to construct a forest land quality comprehensive evaluation indicator system. Based on the TOPSIS model, we introduced the PSO algorithm to design the evaluation model to evaluate the forest land quality and analyze the distribution of forest land quality grades in Hefeng County. We then used the Local Indicator of Spatial Association (LISA) Forests 2021, 12, 325 5 of 25

to explore the spatial aggregation characteristics of forest land quality at the village scale by taking the forest land quality index as a spatial variable. The delineation scheme of forest land protection zones was formulated based on the spatial autocorrelation types, and different zoning management measures were proposed, which can provide a scientific basis and methodological reference for the reasonable delineation of forest land protection zones and meet the real needs of forest land differentiated protection and management in Hefeng, while also serving as a reference for similar regions and countries. This study not only introduced the PSO-TOPSIS model, aiming to explore new ways to evaluate forest land quality, but also incorporated spatial attributes of forest land quality into the development of forest land protection zoning schemes, expanding the means of forest land protection zoning, which can provide a scientific basis and methodological reference for the formulation of forest land rational development and utilization policies, in addition to serving as a reference for similar studies.

2. Materials and Methods 2.1. Study Area Hefeng County, which belongs to Enshi Miao and Tujia of Hubei Province in China, is located between 109◦450–110◦380 E and 29◦380–30◦140 W. This county, which has nine towns and an area of 286,800 ha, is located in the Southwestern Hubei Province in China, bordering Province in China (Figure1a). Hefeng belongs to a subtropical continental monsoon climate with abundant sunshine, four distinct seasons, suitable temperature, and abundant precipitation. The territory of this county is character- ized by long stretches of mountains and gullies, with the terrain gradually decreasing from the northwest to southeast, dominated by high mountains (Figure1b). Hefeng belongs to the subtropical humid evergreen broad-leaved forest region and is rich in forest land resources, with an area of 25.44 million ha, accounting for 88.70% of the total land area. According to the 2018 national economic and social development statistics of Hefeng, the forest coverage rate of the county reached 72.7%. Hefeng, that has an overall sensitive ecological environment with severe soil erosion, is an important ecological function reserve in China [56]. In the past 20 years, with the acceleration of the local urbanization process, much forest land has been converted to arable land and construction land, resulting in a decrease in the amount of forest land [57]. In addition, the quality of forest land of Hefeng county has been severely degraded, mainly due to rapid socioeconomic development, dramatic population growth, and increased market demand. The frequent occurrence of forest fires has exacerbated forest land degradation, resulting in severe soil erosion and loss of biodiversity, which has become a bottleneck affecting the sustainable use of forest land and coordinated economic and social development [58]. Therefore, it is of great significance to evaluate forestland quality scientifically and delineate forest land protection zones reasonably in Hefeng for fine forest land management and to guarantee ecological security of the national land in the local area, and it can also provide a reference for similar countries and regions. Forests 2021, 12, x FOR PEER REVIEW 6 of 25 Forests 2021, 12, 325 6 of 25

Figure 1. Study area: ( aa)) location of of Hefeng County in the Hubei Province, China; ( b) digital elevation map (DEM) of Hefeng County.

2.2. Data Data Collection Collection and Processing The ba basicsic data involved in this study mainly includes the following: (1) the current landland use use map map and and administrative administrative division map were obtained from the Land Use Change Survey Database in 2018 2018 (1:10,000) (1:10,000) provided provided by by the the Natural Natural Resources Resources Bureau Bureau of of Hefeng. Hefeng. (2) Th Thee meteorological data of average annual precipitation, precipitation, average average annual annual temperature, temperature, ◦ ≥10≥10 °CC accumulated accumulated temperature, temperature, which which is the is thesum sum of the of daily the daily average average temperature temperature dur- ◦ ingduring the thecontinuous continuous period period of ≥10 of ≥°C10 in Ca year, in a year,and the and wetness the wetness index index in the in study the study area wareaere wereobtained obtained from month from month-by-month-by-month observations observations in 31 meteorological in 31 meteorological stations stationsdistrib- uteddistributed in Hubei in Province Hubei Province of China of from China 1949 from to 19492018, tofrom 2018, the from National the National Weather Weather Science DataScience Center Data (http://data.cma.cn/, Center (http://data.cma.cn/ accessed on, accessed10 April 2020 on 10). (3) April Slope 2020). was extracted (3) Slope us wasing aextracted 30 m resolution using a digital 30 m resolution elevation digitalmodel elevation(DEM) from model the (DEM)Geospatial from Data the GeospatialCloud Platform Data (http://www.gscloud.cn/,Cloud Platform (http://www.gscloud.cn/ accessed on 22 April, accessed 2020). (4) on Soil 22 Apriltype, 2020).soil layer (4) thickness, Soil type, soil texture,layer thickness, land degradation, soil texture, traffic land location, degradation, and forest traffic disaster location, grad ande forestwere disasterobtained grade from thewere Forest obtained Resources from the Planning Forest Resourcesand Design Planning Survey Database and Design in Survey2018 (1:10,000) Database provided in 2018 by(1:10,000) the Forestry provided Bureau by the of ForestryHefeng. (5) Bureau Soil organic of Hefeng. matter (5) Soil and organic soil pH matter (1 km andresolution) soil pH were(1 km obtained resolution) from were the obtained National from Earth the National System Earth Science System Data Science Center Data Soil Center subcenter Soil (http://soil.geodata.cn/index.html,subcenter (http://soil.geodata.cn/index.html accessed on, accessed 8 May 2020 on 8). May (6) Socioeconomics 2020). (6) Socioeconomics and other statisticaland other data statistical were datafrom were the 2018 from Statistical the 2018 StatisticalYearbook Yearbookand related and agricultural related agricultural statistics instatistics Hefeng. in Hefeng. We used ArcGIS 10.2 software (Environmental Systems Research Institute, Redlands, We used ArcGIS 10.2 software (Environmental Systems Research Institute, Redlands, CA, USA) for the projection transformation and vectorization of each evaluation indicator. CA, USA) for the projection transformation and vectorization of each evaluation indicator. 2.3. Methods 2.3. Methods 2.3.1. Evaluation Indicator System 2.3.1. Evaluation Indicator System The process of evaluation index system construction is shown in Figure2. First, the evaluationThe process unit of evaluation was delineated. index system The evaluation construction unit is isshown an independent in Figure 2. unitFirst with, the evaluationrelatively consistent unit was delineated. natural and The socioeconomics evaluation unit attributes. is an independent The same evaluationunit with relatively unit has consistentsimilar attributes, natural whileand socioeconomics the different unit attributes. has significant The differencessame evaluation [59]. The unit patch has formedsimilar attributes,by overlaying while the the current different land unit use has map, significant soil map, differences and administrative [59]. The unitpatch map formed is often by overlayingused as the the land current evaluation land use unit map, [60,61 soil]. Tomap, facilitate and administrative the investigation unit andmap managementis often used asof the forest land resources, evaluation a surveyunit [60,61] unit. To based facilitate on the the forest investigation land subcompartment and management has of been for- estestablished resources, in a thesurvey forest unit resource based on planning the forest and land design subcompartment survey in China. has been According established to inprevious the forest research resource [27,28 planning], the forest and land design subcompartment survey in China. was usedAccording as the to evaluation previous unit re- searchof forest [27,28], land quality the forest in this land study. subcompartment A total of 80,024 was forest used landas the subcompartments evaluation unit of with forest an landarea ofquality 254,000 in hathis were study. extracted A total fromof 80,024 theForest forest Resourcesland subcompartments Planning and with Design an Surveyarea of 254,000Database ha of were Hefeng extracted in 2018 from (1:10,000). the Forest Resources Planning and Design Survey Data- base of Hefeng in 2018 (1:10,000).

Forests 20212021,, 1212,, 325x FOR PEER REVIEW 78 of 25

The forest land The evaluation unit is delineated. subcompartment

The evaluation indicators are selected and standardized.

Climatic conditions Terrain Soil conditions Socioeconomics

≥10 Ave Ave ℃ Soil Fore rage rage 、 Soil Lan Wet laye Traf st ann ann accu Elev Soil orga d ness Slop Soil r Soil fic disa ual ual mul atio text nic degr inde e type thic pH loca ster tem prec ated n ure matt adat x knes tion grad pera ipita tem er ion s e ture tion pera ture

Evaluation indicator weights are Python The PSO algorithm calculated.

The forest land quality index is The TOPSIS model calculated.

Figure 2. The processprocess ofof evaluationevaluation index index system system construction. construction. Note: Note: PSO PSO is is the the abbreviation abbreviation of Particleof Particle Swarm Swarm Optimization. Optimiza- TOPSIStion. TOPSIS is the is abbreviation the abbreviation of Technique of Technique for Order for Order Preference Preference by Similarity by Similarity to Ideal to Solution.Ideal Solution.

Table 1. ForestSecond, land quality the evaluation indicator indicators grading were standards selected and and their standardized. scores. The study of an indicator system is the basis for land evaluationScore [62]. The factors affecting the quality of Criteria Layer Indicator Layer Weight forest land are complex,10 involving8 natural, ecological6 environment,4 and socioeconomics.2 Average annual tempera- Natural0.12 factors mainly>16.0 include14.0 climate,–16.0 soil, hydrology,12.0–14.0 and terrain,10.0–12.0 which are<10.0 the basis ture/°C for the development of forestry and are the basic indicators reflecting the quality of forest Average annual precipita- Climatic condi- 0.11 >2000 1600–2000 1200–1600 800–1200 <800 tion/mm land. Socioeconomics factors generally affect the quality of forest land by influencing its tions ≥10 °C accumulated tem-management level, mainly including land use, land management, location, and disaster, 0.08 >7000 6000–7000 6000–5000 5000–4000 <4000 perature/°C which are also important factors affecting the quality of forest land. Climate is the basis Wetness index for the0.1 photosynthesis1 >120 of vegetation100–120 and has a80 strong–100 influence60– on80 the quality<60 of forest Elevation/m 0.04 <200 200–800 800–1400 1400–2000 >2000 Terrain land. According to previous research, temperature and precipitation are generally selected Slope/° 0.02 <5 5–14 15–24 25–34 ≥35 to evaluate the climatic production potential of forest land [63]. In addition, forest land Fresh soil, desert Drifting ash soil, quality evaluationBlack indicators soil, have a time-scale effect, and differentsoil, sandy indicators black have different chestnut calcium scales for thebrown time conifer- change.Tide According soil, gray forest to the response timesoil, of limestone soil physical soil, C andoarse chemicalbone soil, soil, chestnut brown ous soil, brown soil, gray-brown soil, peat soil, purple grass felt soil, gray- properties, the response time of the soil typesoil, is greater yellow cotton than 1000 years, the response time of Soil conditions Soil type 0.01 loam, black cal- dry red soil, yellow soil, red soil, white brown desert soil, soil layer thickness is between 100 and 1000soil, years, brick andred soil, the response time of soil texture is careous soil, loam, yellow-brown pulp soil, silt soil, red clay soil, cracked red soil, volcanic ash located betweenbrown 10 soil, and dark 100 yearssoil [64 ]. Soil organic matter ismountain the main meadow source of vegetationsoil soil, yellow-brown nutrients, andbrown it is alsoloam therefore an important indicator ofsoil, soil forested fertility [65]. Soil pH is loam closely related to fertilizer uptake efficiency, and most vegetationmeadow growssoil best when it is

Forests 2021, 12, 325 8 of 25

between 6.5 and 7.5 [66]. Land degradation is the main factor limiting the improvement of forest land quality [28]. Therefore, soil organic matter, soil type, soil texture, soil layer thickness, soil pH, and land degradation were selected as indicators of soil environment in forest land. The terrain is closely related to forest land quality and determines the spatial distribution of forest land quality. Elevation and slope were selected to evaluate the suitability of forest land [67]. Socioeconomic conditions affect the level of forest land management, and the transportation location and forest disaster grade were selected to assess the economic quality of forest land [24]. Based on the above analysis, the principles of comprehensiveness, dominance, and differentiation [46] were followed in this study, referring to the evaluation system es- tablished in the Technical Regulations for Defining Forest Land Border in Forest Land Planning on Protection and Utilization developed by the National Forestry Administration of China [68]. Fourteen indicators of average annual temperature, average annual precipi- tation, ≥10 ◦C accumulated temperature, wetness index, elevation, slope, soil type, soil layer thickness, soil organic matter, soil texture, soil pH, land degradation, traffic location, and forest disaster grade were selected from four dimensions—climatic conditions, terrain, soil conditions, and socioeconomics—to construct a forest land quality evaluation indicator system. To eliminate the influence of the evaluation indicator scale, the indicators were graded according to their influence on the quality of the forest land and their scores are assigned. The indicator score is assigned based on its indicator grade. The higher the score, the higher the quality of forest land. Indicators were standardized concerning the Technical Regulations for Defining Forest Land Border in Forest Land Planning on Protection and Utilization [68], Technical Regulations for Continuous Forest Inventory [69], Regulation for Gradation on Agriculture Land Quality [70], and Cultivated Land Quality Grade [71]. The evaluation indicator system of forest land quality is shown in Table1. Third, evaluation indicator weights were calculated. The PSO algorithm is an evo- lutionary computational technique proposed by Kennedy J. and Eberhart R. in 1995 [72]. The basic principle of PSO is to move individuals in the population to good positions according to the size of their adaptation to the environment, which is not only fast in computation but also has a strong global optimal search capability for nonlinear prob- lems [41]. In this study, we constructed a nonlinear programming model of evaluation indicator weights by aiming at minimizing the sum of the distances between the weights of evaluation indicators and their maximum and minimum values. We then calculated the weight of each indicator by PSO, which can enter into mining the nonlinear information implied by the data. The calculation steps are as follows. (1) The original evaluation indicators are normalized to obtain the judgment matrix X.  X = (X )  ij m×n xij Xij = m (1)  ∑ xij i=1

where Xij is the ratio of the indicator value of the ith evaluation unit under the jth indicator, m is the number of evaluation units, n is the number of evaluation indicators, and xij is the indicator value of the ith evaluation unit under the jth indicator. (2) Based on the judgment matrix X, the weight adaptation equation is constructed. Let the optimal object be H = (1, 1, . . . , 1)T and the inferior object be L = (0, 0, . . . , 0)T. The objective is then as follows.

   n n n m (1 − X )2 + X2 = 2 ij ij  ∑ wj 1 min f (w) = f (w) = w s.t = (2) ∑ j ∑ ∑ j  ×  j 1 j= j= i= m n  1 1 1 wj ≥ 0

where minf (w) is the planning equation of the weight, fj(w) is the planning equation of the weight of the jth indicator, and wj is the weight of the jth indicator. Forests 2021, 12, 325 9 of 25

Table 1. Forest land quality evaluation indicator grading standards and their scores.

Score Criteria Layer Indicator Layer Weight 10 8 6 4 2 Average annual 0.12 >16.0 14.0–16.0 12.0–14.0 10.0–12.0 <10.0 temperature/◦C Average annual 0.11 >2000 1600–2000 1200–1600 800–1200 <800 Climatic conditions precipitation/mm ≥10 ◦C accumulated 0.08 >7000 6000–7000 6000–5000 5000–4000 <4000 temperature/◦C Wetness index 0.11 >120 100–120 80–100 60–80 <60 Elevation/m 0.04 <200 200–800 800–1400 1400–2000 >2000 Terrain Slope/◦ 0.02 <5 5–14 15–24 25–34 ≥35 Fresh soil, desert soil, Drifting ash soil, Black soil, brown sandy black soil, Tide soil, gray forest chestnut calcium soil, Coarse bone soil, coniferous soil, limestone soil, peat soil, gray-brown soil, chestnut brown soil, grass felt soil, brown loam, black soil, purple soil, red Soil type 0.01 dry red soil, yellow yellow cotton soil, gray-brown desert calcareous soil, soil, white pulp soil, loam, yellow-brown brick red soil, red soil, red clay soil, brown soil, dark silt soil, mountain soil soil, volcanic ash soil, cracked soil brown loam meadow soil, yellow-brown loam forested meadow soil Soil conditions Soil layer thickness/cm 0.04 >8 40–80 <40 Loamy sandy soil, Soil texture 0.06 Loamy soil Clay, sandy clay sandy loam Soil organic 0.12 >40 30–40 20–30 10–20 <10 matter/(g/kg) Soil pH 0.08 6.0–7.9 5.5–6.0; 7.9–8.5 5.0–5.5; 8.5–9.0 4.5–5.0 <4.5; ≥9.0 Land degradation 0.02 None Light Moderate Intense High intensity Traffic location 0.09 First grade Second grade Third grade Fourth grade Fifth grade Socioeconomics Forest disaster grade 0.10 None Light Medium Heavy Forests 2021, 12, 325 10 of 25

To calculate the weights using the PSO, the planning Equation (2) is transformed into an adaptation equation.   n 2 n m 2 2 (1 − Xij) + Xij P(w) = E( w − 1) + F w2 (3) ∑ j ∑ ∑ j  ×  j=1 j=1 i=1 m n

where E and F are penalty factors, whose values vary depending on the judgment matrix R. (3) The PSO is applied to solve the weights.

 v = w ∗ v + c ∗ rand() ∗ (p − x ) + c ∗ Rand() ∗ (p − x ) id id 1 id id 2 gd id (4) xid = xid + vid

where xid is the ith particle, vid is the velocity of particle i, pid is the best-adapted value, pgd is the indicator number of the best-adapted value, w is the inertia weight, c1 and c2 are acceleration constants, rand() and Rand() are random values in the range [0,1], and d is the dimensionality of the search space. In this study, the PSO was used to solve the weights of each evaluation indicator using Python 3.8, which was designed by Rossum G.V. in the early 1990s [73] (Table1) . Its parameters in Python were set as follows: the number of iterations was 1000, the number of populations was 200, the inertia weight was 1.0, the spatial dimension was 14, the acceleration constant c1 = c2 = 1.8, and the incremental threshold of the optimal fitness value was 0.002. Finally, the forest land quality index was calculated. TOPSIS is a comprehensive evaluation method first proposed by Hwang C.L. and Yoon K. in 1981 [43]. Based on the normalized original evaluation indicator matrix, the cosine is used to calculate the optimal and inferior solutions of each evaluation indicator. The Euclidean distance between the evaluation indicator and the optimal and inferior solutions is used as the criterion for the evaluation solutions [47]. TOPSIS is widely used in land evaluation in various parts of world [42,46,74,75]. Jozi S.A. and Majd N.M. [76] used the TOPSIS and AHP models to evaluate ecological land capacity evaluation of Dehloran County. Luo W.B. and Tong Z. [77] used the TOPSIS model with information entropy weights to construct a rural land consolidation performance evaluation index system between 31 Chinese provinces from 2003 to 2007. Therefore, in this study, we used the improved TOPSIS model, which introduced weights [46] to evaluate the forest land quality and its calculation process is as follows. (1) Standardization of evaluation indicators. The extreme value method is usually applied to standardize the evaluation indicators to determine the status of the original values of each evaluation indicator in the weights. (2) Weighted judgment matrix construction. The indicator weight matrix U calculated based on the PSO is involved in the construction of the judgment matrix, i.e., the P = (p ) X weighted judgment matrix ( ij m×n) is obtained by multiplying the matrix with its weight U.     p11 p12 ... p1n x11.u1 x11.u1 ... x11.u1  p p ... p n   x .u x .u ... x n.u  P =  21 22 2  =  21 2 21 2 2 2  (5)  ......   ......  pm1 pm1 pmn xm1.um xm1.um ... xmn.um

(3) The optimal solution P+ and the inferior solution P− are sought.

+   + + + P = maxpij j = 1, 2, . . . , n = p1 , p2 ... pn −   − − − (6) P = maxpij j = 1, 2, . . . , n = p1 , p2 ... pn Forests 2021, 12, 325 11 of 25

(4) Calculate the distance. Calculate the R+ and R− distances of each evaluation unit from the optimal solution, respectively.

s n + + 2 Ri = ∑ (pij − pi ) , i = 1, 2, . . . m j=1 s n − − 2 (7) Ri = ∑ (pij − pi ) , i = 1, 2, . . . m j=1

(5) Calculate the closeness of each evaluation unit to the optimal solution Ci.

− Ri Ci = + − (8) Ri + Ri

where larger Ci means better quality of the ith evaluation unit and Ci takes values in the range of [0,1]. When Ci is 0, it means the worst quality of forest land, and when Ci is 1, it means the best quality of forest land.

2.3.2. Spatial Autocorrelation (1) Local Indicator of Spatial Association The first law of geography states that everything is correlated with each other and the closer things are to each other, the higher the correlation [78]. That is, geographic entities show certain correlations in their spatial distribution under the influence of both spatial attraction and spatial diffusion effects [79]. Spatial autocorrelation provides an effective method for exploring the spatial correlation patterns of geographic entities [80]. Spatial autocorrelation is a method to study the correlation between regional variables and their neighboring variables in terms of spatial location, by detecting the dependence of a location variant on its neighboring locations to determine whether it is spatial autocorrelation [81]. In spatial autocorrelation, one of the more commonly used parameters is the global Moran’s I index, which is calculated as follows:

n n n n 2 I = ∑ ∑ Wij(Xi − X)(Xj − X)/S ∑ ∑ Wij (9) i=1 i=1 i=1 i=1

where n is the number of samples of variable X, Xi, and Xj are the actual measurements of 2 the samples at positions i and j, respectively, S is the variance, X is the mean, and Wij is the value of the spatial weight matrix. In 1995, Anselin L. [82] developed the concept of the Local Indicator of Spatial Associ- ation (LISA), which was a decomposed form of global spatial autocorrelation, reflecting the degree of correlation between a spatial unit and its neighboring spatial units on the value of indicators [80], and its expression is as follows:

Ii = Ai∑ Wij Aj j s n (10) (x − x) 1 2 Ai = i / n ∑ (xi − x) i=1

where Ai is the normalized value of the observed values of indicator i of the spatial unit. Xi and Xi are the same as in Equation (9). The spatial pattern can be visualized by combining the local spatial autocorrelation index with the Moran scatter plot map [81], which is divided into four quadrants, repre- senting four different types of autocorrelations [83]. The first and third quadrant points represent spatial similarity. The first quadrant points show high indicator values with high indicator neighbors (high-high), while the third quadrant points show low indicator values with low indicator neighbors (low-low). The second and fourth quadrant points indicate Forests 2021, 12, 325 12 of 25

spatial dissimilarity. The second quadrant points show low indicator values surrounded by high indicator neighbors (low-high). In contrast, the fourth quadrant points show the high indicator values surrounded by low indicator neighbors (high-low). (2) Spatial Unit and Spatial Variable The use of a subcompartment of forest land as an evaluation unit is to analyze the quality of forest land at a microscopic scale. Considering the large study area and the small size of the forest land subcompartment, it is difficult to identify the results of local spatial autocorrelation. In addition, forest land protection zoning is a systematic project, focusing more on medium- and macro-scale protection and utilization. Therefore, in this study, from the practice of forest land protection, the administrative village was taken as the spatial unit, and the village forest land quality index was used as a spatial variable to explore the zoning scheme of forest land conservation at the village scale, coupling the integrated influence of forest land natural, socioeconomics, and spatial attributes in forest land protection. Based on the evaluation of the forest land subcompartment quality, the quality of forest land at the village scale is obtained by taking the ratio of the area of each forest land subcompartment to the total area of forest land subcompartment in the village as the weights, and its calculation is as follows.

Fim × sim Fm = (11) ∑ sim

where Fm is the average forest land quality index of the mth village; Fim is the forest land quality index of the ith forest land subcompartment in the mth village; Sim is the area of the ith forest land subcompartment in the mth village. Meanwhile, the LISA and Moran scatter plot map of this study were implemented with the help of ArcGIS 10.2 (Environmental Systems Research Institute, Redlands, CA, USA) and GeoDa 1.14 (The University of Chicago, Chicago, IL, USA).

3. Results 3.1. Forest Land Quality Evaluation Results 3.1.1. Spatial Distribution of Evaluation Index From the calculation results, the range of Forest Land Quality Index (FLQI) was 0.4091–0.8601, and the county average index was 0.6337, indicating that the overall forest land quality was high. The spatial distribution of the FLQI (Figure3) showed that the FLQI is higher in the central and southeastern parts of the county and lower in the northwestern parts. According to the statistical characteristics of FLQI of towns (Table2), there was some variability in the mean values of FLQI in different towns. According to ANOVA, the p-value was 0.004 at the significance level of 0.05. It is thus clear that p < 0.05 indicates that the variability of FLQI between towns was relatively significant in general. The mean values of the FLQI in Zouma and Yanzi are relatively large, while the mean values of the FLQI in Rongmei, Tielu, and Taiping are relatively small. From the coefficient of variation of the FLQI, the FLQI in Xiaping fluctuated the most, while that in Wuyang fluctuated the least. Forests 2021, 12, x FOR PEER REVIEW 13 of 25

Table 2. Statistical characteristics of forest land quality index (FLQI) of towns.

Name of Towns Mean Value Standard Deviation Maximum Value Minimum Value Coefficient of Variation Rongmei 0.61 0.08 0.80 0.41 13.34 Taiping 0.61 0.08 0.81 0.42 12.39 Tielu 0.61 0.07 0.85 0.42 11.34 Wuyang 0.64 0.06 0.77 0.44 9.61 Wuli 0.63 0.07 0.81 0.42 11.46 Xiaping 0.63 0.08 0.86 0.44 13.43 Yanzi 0.65 0.07 0.86 0.42 10.21 Forests 2021, 12, 325 Zhongying 0.62 0.07 0.83 0.47 11.69 13 of 25 Zouma 0.66 0.07 0.81 0.44 10.48

Figure 3. Spatial distribution of forest land quality index (FLQI) in Hefeng. Figure 3. Spatial distribution of forest land quality index (FLQI) in Hefeng.

Table3.1.2. 2. Statistical Spatial characteristics Distribution ofof forest Evaluation land quality Grades index (FLQI) of towns. Name of Towns Mean ValueTo Standard explore Deviationthe variability Maximum of quality Value among Minimum forest land Value subcompartment, Coefficient of according Variation Rongmei 0.61to the natural breakpoint 0.08 method, the 0.80 quality of forest 0.41land was divided into 13.34 four grades: Taiping 0.61first grade, second 0.08 grade, third grade, 0.81 and fourth grade, 0.42 with areas of 80,692, 12.39 68,372, Tielu 0.6158,043, and 46,928 0.07 ha, respectively. 0.85The largest area of 0.42first-grade forest land 11.34 was 31.76%, Wuyang 0.64and the smallest 0.06 area of fourth-grade 0.77 forest land was 18.47%. 0.44 In terms of the 9.61 distribution Wuli 0.63of forest land 0.07quality grades (Figure 0.81 4), the first-grade 0.42 forest land was the 11.46 most widely Xiaping 0.63 0.08 0.86 0.44 13.43 distributed, mainly concentrated in the southeastern low mountain areas. The natural en- Yanzi 0.65 0.07 0.86 0.42 10.21 Zhongying 0.62vironment of the 0.07 region was excellent. 0.83 Its climate was 0.47 suitable, the terrain 11.69was relatively Zouma 0.66flat, and the ability 0.07 of soil and water 0.81 conservation was 0.44 strong. In addition, 10.48its soil condi- tions were good. Its soil type was mainly brown loam with a loamy texture, thick soil layer, and high soil nutrient content. In addition, convenient transportation conditions in 3.1.2. Spatial Distribution of Evaluation Grades this area effectively enhanced the management of forest land. Therefore, the excellent nat- ural andTo exploresocioeconomic the variability conditions of quality of this among area ensured forest land the stability subcompartment, and high quality according of theto theforest natural land. breakpoint method, the quality of forest land was divided into four grades: first grade, second grade, third grade, and fourth grade, with areas of 80,692, 68,372, 58,043, and 46,928 ha, respectively. The largest area of first-grade forest land was 31.76%, and the smallest area of fourth-grade forest land was 18.47%. In terms of the distribution of forest land quality grades (Figure4), the first-grade forest land was the most widely distributed,

mainly concentrated in the southeastern low mountain areas. The natural environment of the region was excellent. Its climate was suitable, the terrain was relatively flat, and the ability of soil and water conservation was strong. In addition, its soil conditions were good. Its soil type was mainly brown loam with a loamy texture, thick soil layer, and high soil nutrient content. In addition, convenient transportation conditions in this area effectively enhanced the management of forest land. Therefore, the excellent natural and socioeconomic conditions of this area ensured the stability and high quality of the forest land. Forests 2021, 12, x FOR PEER REVIEW 14 of 25 Forests 2021, 12, 325 14 of 25

Figure 4. Spatial distribution of forest land quality grades in Hefeng. Figure 4. Spatial distribution of forest land quality grades in Hefeng. Second-grade forest land was also more commonly distributed in Hefeng, mainly Second-grade forest land was also more commonly distributed in Hefeng, mainly located in the southeastern medium mountain areas, adjacent to first-grade forest land located(Figure in4). the The southeastern natural conditions medium in mountain this area wereareas, also adjacent superior, to first with-grade a more forest suitable land (Figureclimate, 4). a smallThe natural slope, a conditions soil type mainly in this of area yellow-brown were also loam,superior, a soil with layer a thicknessmore suitable above climate,40 cm, aa soilsmall organic slope, matter a soil contenttype mainly between of yellow 30 and-brown 40 g/kg, loam, and a pHsoil betweenlayer thickness 5.5 and above6.0. The 40 cm, forest a soil land organic quality matter in this content region between has been 30 degraded and 40 g/kg, to aand certain a pH extent between due 5.5 to andthe 6.0. terrain, The whichforest land can bequality improved in this through region ha soils been improvement degraded toto increasea certain theextent water due and to thefertilizer terrain, retention which can capacity be improved of the soil. through soil improvement to increase the water and fertilizerThird-grade retention forestcapacity land of the also soil. occupied a high proportion of the area, mainly in the northwesternThird-grade medium forest land and highalso occupied mountain a areas,high proportion adjacent to of second-grade the area, mainly forest in landthe n(Figureorthwestern4). The medium slope was and larger, high the mountain elevation areas, was adjacent generally to above second 1400-grade m, and forest the land soil (Figureand water 4). The conservation slope was capacity larger, the were elevation poor in was this generally region. In above addition, 1400 the m, climate and the in soil the andregion water was conservation highly volatile, capacity with frequentwere poor extreme in this weather region. eventsIn addition, [84]. The the thicknessclimate in of the the regionsoil layer was was highly thinner, volatile, the soilwith was frequent more infertile,extreme landweather degradation events [84] was. The more thickness severe, theof thefrequency soil layer of was forest thinner, fires was the higher soil was [85 ],more and infertile, the traffic land conditions degradation were unfavorablewas more severe, due to thethe frequency terrain in of this forest region. fires Therefore, was higher the [85] quality, and of the forest traffic land conditions in this region were wasunfavorable low, and duethe to main the limitingterrain in factors this region. were terrain, Therefore, climate, the quality and soil. of Forforest this land type in of this forest region land, was soil low,development and the main and utilizationlimiting factors management were terrain, must beclimate, strengthened and soil. to For prevent this type soil erosion.of forest land, soilFourth-grade development forest and land utilization had the least management area and was must mainly be strengthened located in the to northwesternprevent soil erosion.high mountain areas, adjacent to third-grade forest land (Figure4). The climate in the regionFourth was- highlygrade forest volatile, land with had frequent the least extreme area and temperature was mainly and located precipitation in the northwest- events [84]. ernThis high region mountain was at highareas, altitude, adjacent generally to third- abovegrade 2000forest m, land with (Figure large slopes, 4). The the climate most in severe the regionsoil erosion, was highly insufficient volatile, soil with nutrients, frequent and extreme severe temperature soil acidification. and precipitation The main limitingevents [84]factors. This for region the quality was at of high forest altitude, land in generally this region above were climate,2000 m, terrain,with large and slopes, soil. In the addition, most severeforest soil fires erosion, were frequent insufficient in the soil region, nutrients, and the and ecological severe soil degradation acidification. of forestThe main land lim- was itingmore factors severe, for which the quality had a of greater forest impact land in on this the region quality were of forestclimate, land terrain, [85]. and Strict soil. forest In addition,land management forest fires and were protection frequent measures in the region, must and be taken the ecological to reduce thedegradation frequency of of forest forest landdisasters, was more prevent severe, the which ecological had a degradation greater impact of on forest the land,quality improve of forest soil land fertility, [85]. Stric andt forestreduce land soil management acidification. and protection measures must be taken to reduce the frequency In general, on the regional macro scale, forest land quality was highest in the low mountain areas of Hefeng County, followed by the medium mountain areas, medium and

Forests 2021, 12, 325 15 of 25

high mountain areas, and high mountain areas. It can be seen that the quality of forest land was closely related to the terrain, which determined the spatial pattern of forest land quality. In addition, on the town mesoscale, the elevation and the slope reflecting important charac- teristics of the terrain have important impacts on climate and soil physical and chemical properties. The elevation has a great influence on accumulated temperature, effective soil nutrients, and soil pH. As the elevation increases, the accumulated temperature gradually decreases, soil nutrients have a certain degree of decline, and soil pH shows an obvious upward trend, which has a greater impact on the growth of forest trees and decreases the quality of forest land [86]. The slope has a great influence on the soil thickness, soil water and fertilizer conditions, and the growth of trees [27]. The smaller the slope is, the more favorable the growth of forest trees is, and the higher the quality of the forest land is. Furthermore, factors such as climate change, soil fertility, transportation location, and forest fires also have a great influence on the quality of forest land. Thus, on the town mesoscale, there is some variation in forest land quality (Table3). The first-grade forest land was mainly distributed in Zouma, Yanzi, Wuli, and Zhongying with an area of 28.40%, 16.05%, 12.35%, and 12.35%, respectively, and a total area of 69.15%. The second-grade forest land was mainly concentrated in Yanzi, Zouma, and Wuli, accounting for 14.71%, 14.71%, and 13.24% of the area, respectively, with a total area of 42.66%. The third-grade forest land was mainly distributed in Taiping, Zhongying, and Rongmei, with an area of 15.52%, 13.79%, and 13.79%, respectively. Fourth-grade forest land was mainly distributed in Zhongying, Taiping, and Rongmei, accounting for 17.02%, 17.02%, and 17.02% of the area, respectively. It can be seen that the overall quality of forest land in Zouma, Yanzi, and Wuli was higher, with a more suitable climate, a low slope, and convenient transportation, and the soil can better retain water and fertilizer. The quality of forest land in Zhongying, Rongmei, and Taiping was generally low. The climate was poor, the slope was large, the soil erosion was more severe, the soil fertility was poor, the land degradation was severe, and forest disasters were more severe in this region. In addition, it can be seen that, even in areas with the same landform type, there is some variation in forest land quality. For example, both Rongmei and Zouma in Hefeng County had lower elevation (Figure1), but compared with Zouma, the forest land quality in Rongmei was lower (Figure4), which was due to the fact that Rongmei is the center town of socioeconomic development in Hefeng County, with a more developed social economy and a high intensity of forest land utilization, leading to soil erosion, forest disasters, and forest land degradation that are more severe.

Table 3. Area statistics of forest land quality grades in towns.

First Grade Second Grade Third Grade Fourth Grade Towns Area/0000 ha Proportion/% Area/0000 ha Proportion/% Area/0000 ha Proportion/% Area/0000 ha Proportion/% Rongmei 6 7.41 6 8.82 8 13.79 8 17.02 Taiping 6 7.41 7 10.29 9 15.52 8 17.02 Tielu 4 4.94 8 11.76 7 12.07 4 8.51 Wuyang 4 4.94 6 8.82 4 6.90 2 4.26 Wuli 10 12.35 9 13.24 7 12.07 7 14.89 Xiaping 5 6.17 4 5.88 3 5.17 3 6.38 Yanzi 13 16.05 10 14.71 5 8.62 3 6.38 Zhongying 10 12.35 8 11.76 8 13.79 8 17.02 Zouma 23 28.40 10 14.71 7 12.07 4 8.51

3.2. Spatial Autocorrelation Results Taking the administrative village as a spatial unit and the village-scale FLQI as a spatial variable, the global spatial autocorrelation index of forest land quality in Hefeng was calculated to be 0.7562, indicating that the county forest land quality had a strong similarity in spatial distribution and a certain spatial aggregation characteristic. The LISA types of forest land quality (Figure5a) were mapped, reflecting the spatially clustered areas of forest land quality. Forests 2021, 12, x FOR PEER REVIEW 16 of 25

Taking the administrative village as a spatial unit and the village-scale FLQI as a spatial variable, the global spatial autocorrelation index of forest land quality in Hefeng was calculated to be 0.7562, indicating that the county forest land quality had a strong similarity in spatial distribution and a certain spatial aggregation characteristic. The LISA types of forest land quality (Figure 5a) were mapped, reflecting the spatially clustered areas of forest land quality. From the results of LISA, there were five LISA types: high-high (HH), high-low (HL), low-high (LH), low-low (LL), and nonsignificant (NS) in village-scale forest land quality in the county. In terms of number, the spatial similarity type (HH and LL) accounted for 48.51% of the total number of administrative villages, the spatial dissimilarity type (HL and LH) accounted for 35.15%, and the NS accounted for 16.34%. In terms of spatial dis- tribution, the spatial distribution of similarity types (HH and LL) was more clustered, while the spatial distribution of dissimilarity types (HL and LH) was generally dispersed. The HH areas were mainly distributed in Zouma, Wuli, and Yanzi, where, in the county ranked first, the climate was suitable, the slope was small, the soil water and fertilizer retention ability was strong, the forest resources were rich, and the forest coverage rate was above 70%. Therefore, the quality of the forest land in this region was high. The LL areas were mainly concentrated in Rongmei and Taiping, where, in the center of the county’s economic development, forest land resources were relatively small, and the de- gree of fragmentation was high. As a result, forest land quality in this region was generally low due to severe disturbance by human activities. The HL areas were mainly concen- trated in Zhongying and Wuyang. Due to the influence of the low quality of forest land in the surrounding towns (including Rongmei and Taiping), the forest land quality in this region was medium. The LH areas were mainly concentrated in southeastern Zouma and northern Yanzi, which were mostly distributed around the HH areas. The forest land qual- ity was medium due to the influence of high-quality forest land in Zouma. The NS areas were mainly distributed in northern Tielu and Xiaping, where the quality of forest land Forests 2021, 12, 325 was randomly distributed, with both high grades close to the HH areas and low grades16 of 25 located within the LL areas.

Figure 5. (a) Local Indicator of Spatial Association (LISA) type map of forest land quality in Hefeng; (b) forest land Figure 5. (a) Local Indicator of Spatial Association (LISA) type map of forest land quality in Hefeng; (b) forest land pro- protectiontection zoning zoning map. map. From the results of LISA, there were five LISA types: high-high (HH), high-low (HL), low-high (LH), low-low (LL), and nonsignificant (NS) in village-scale forest land quality in the county. In terms of number, the spatial similarity type (HH and LL) accounted for 48.51% of the total number of administrative villages, the spatial dissimilarity type (HL and LH) accounted for 35.15%, and the NS accounted for 16.34%. In terms of spatial distribution, the spatial distribution of similarity types (HH and LL) was more clustered, while the spatial distribution of dissimilarity types (HL and LH) was generally dispersed. The HH areas were mainly distributed in Zouma, Wuli, and Yanzi, where, in the county ranked first, the climate was suitable, the slope was small, the soil water and fertilizer retention ability was strong, the forest resources were rich, and the forest coverage rate was above 70%. Therefore, the quality of the forest land in this region was high. The LL areas were mainly concentrated in Rongmei and Taiping, where, in the center of the county’s economic development, forest land resources were relatively small, and the degree of fragmentation was high. As a result, forest land quality in this region was generally low due to severe disturbance by human activities. The HL areas were mainly concentrated in Zhongying and Wuyang. Due to the influence of the low quality of forest land in the surrounding towns (including Rongmei and Taiping), the forest land quality in this region was medium. The LH areas were mainly concentrated in southeastern Zouma and northern Yanzi, which were mostly distributed around the HH areas. The forest land quality was medium due to the influence of high-quality forest land in Zouma. The NS areas were mainly distributed in northern Tielu and Xiaping, where the quality of forest land was randomly distributed, with both high grades close to the HH areas and low grades located within the LL areas.

3.3. Forest Land Protection Zoning 3.3.1. Forest Land Protection Zoning Standards and Protection Measures Theories and practices related to regional development show that there are diffusion and polarization effects between regions that can expand or reduce spatial differences between regions [87]. In general, the spatial similarity types HH and LL are a reflection of the spatial diffusion effect, while the spatial dissimilarity types LH and HL are a reflection of the spatial polarization effect [88]. Under the interaction of the two effects, based on the results of LISA, and combining the characteristics of the five spatial autocorrelation types, the county’s forest land protection zones can be divided into three types: key protected zones (KPZs), active protected zones (APZs), and general protected zones (GPZs) (Figure5b). The protection zoning standards are shown in Table4. Forests 2021, 12, 325 17 of 25

Table 4. Forest land protection zoning standards.

Local Indicator of Spatial Protection Zoning Type Typical Area Characteristics Association (LISA) Type The forest land quality was Key protection zone (KPZ) HH Zouma, Wuli, and Yanzi high and its spatial distribution was aggregated. The forest land quality Active protection zone (APZ) LH, HL, and NS (medium) Zhongying and Wuyang was medium. The forest land quality was General protection zone (GPZ) LL and NS (low) Rongmei, Taiping, and Tielu low, but its spatial distribution was aggregated.

The HH area is one of an aggregation of patches with a high FLQI, which generally has high forest land quality and entails strong aggregation characteristics in spatial distribution. Therefore, it is designated as an KPZ. In terms of protection measures, it is necessary to actively maintain and improve the quality of existing forest land, strengthen the intensity of protection, strictly protect the good natural ecological and environmental conditions of forest land, greatly reduce the damage to forest land resources from human activities, and strengthen the impact of spatial diffusion effects. In the HL area, the high-quality forest land is concentrated in the center, while its surroundings are mostly surrounded by the low-quality forest land. Under the influence of the spatial polarization effect, the high-quality forest land is easily assimilated by the low- quality forest land, thus evolving into an LL area. Therefore, we should actively strengthen the protection of the central high-quality forest land, reduce the impact of the surrounding low-quality forest land on it, and gradually expand the range of protection. In the contrast, in the LH area, the high-quality forest land is distributed around the low-quality forest land. We should actively improve the protection and improvement of the central low-quality forest land, and emphasize the diffusion effect of the surrounding high-quality forest land to promote their evolution to an HH. On the other hand, non-forestry construction on the low-quality forest land should be avoided to minimize the impact of its polarization effect on the surrounding high-quality forest land. Therefore, the HL and LH are suitable for designation as APZs. The LL area is one of an aggregation of patches with low FLQI, which generally has low forest land quality and entails strong aggregation characteristics in spatial distribution. Therefore, the LL area is suitable for designation as a GPZ. Its improvement should be treated differently, and comprehensive, prioritized, and gradual forest land protection measures should be considered. In addition, if the forest land is to be deagriculturalized, the LL area is an ideal choice. In addition, according to the statistical results, in the NS area, there is both high-quality forest land close to HH and low-quality forest land. Therefore, the NS areas were further classified into two types (medium and low) by the natural breakpoint method: an APZ and a GPZ, respectively. Some conditional protection measures were adopted in conjunction with forest land protection and ecological civilization construction.

3.3.2. Analysis of the Results of Forest Land Protection Zoning To further verify the consistency between the results of forest land protection zoning and the results of forest land quality evaluation, the zoning types and forest land qual- ity grades were compared and analyzed (Table5). First-grade forest land in the KPZs accounted for 56.79% of the total area of first-grade forest land in the county, and first- and second-grade forest land cumulatively accounted for 86.08% of the total area of KPZs. The second- and third-grade forest land in the APZs accounted for 50.00% and 39.66% of the total area of second- and third-grade forest land in the county, respectively. The first- and second-grade forest land cumulatively accounted for 63.63% of the total area of the APZs. The third- and fourth-grade forest land in the GPZs accounted for 46.55% and 65.96% of Forests 2021, 12, 325 18 of 25

the total area of third- and fourth-grade forest land in the county, respectively. The third- and fourth-grade forest land cumulatively accounted for 76.32% of the total area of the GPZs. It can be seen that the KPZs covered most of the high-grade forest land in the county, while the GPZs covered most of the low-grade forest land in the county, and most of the medium-grade forest land was assigned as APZs, indicating that the forest land protection zoning scheme based on the LISA of forest land quality was basically consistent with the forest land quality evaluation results.

Table 5. Area statistics of forest land quality grades compared with protection zones.

First Grade Second Grade Third Grade Fourth Grade Protection Type Total Area/0000 Proportion Area/0000 Proportion Area/0000 Proportion Area/0000 Proportion ha (n)/% ha (n)/% ha (n)/% ha (n)/% Area/0000 ha 46 58.23 22 27.85 8 10.13 3 3.80 79 KPZs Proportion 56.79 32.35 13.79 6.38 31.10 (m)/% Area/0000 ha 29 29.29 34 34.34 23 23.23 13 13.13 99 APZs Proportion 35.80 50.00 39.66 27.66 38.98 (m)/% Area/0000 ha 6 7.89 12 15.79 27 35.53 31 40.79 76 GPZs Proportion 7.41 17.65 46.55 65.96 29.92 (m)/% Total 81 31.89 68 26.77 58 22.83 47 18.50 254

4. Discussion 4.1. Forest Land Quality Indicator System Construction Whether the construction of the forest land quality evaluation indicator system is reasonable or not is directly related to the accuracy of evaluation results. How to reasonably determine the indicator system according to the purpose of an evaluation is the basic work of forest land quality evaluation. Mo K. [89] constructed a forest land quality evaluation indicator system from three aspects: soil conditions, terrain, and forest conditions. Deng W.Q. [90] established a comprehensive evaluation system of forest land quality from soil conditions and meteorological conditions. There is a close relationship between forest land quality and factors such as soil fertility, terrain, and management [91]. Due to the diversity of factors affecting forest land quality and regional variability, the current forest land quality evaluation indicator system is still not unified [92]. Additionally, the existing indicator system takes more into account factors such as soil fertility and management that affect the quality of forest land and ignores the impact of factors such as climate change and forest fires on land ecological degradation [89]. Hubei Province, which is situated in the middle reaches of the Yangtze River and belongs to the east–west, north–south climate transition zone, is a sensitive area of climate change. According to the Historical Information on Natural Disasters in Hubei Province, it is found that the frequency of droughts and floods in Hubei Province has increased since the 20th century. Gao X. et al. [93] also pointed out that the main areas of extreme temperature in Hubei Province in the last 20 years were concentrated in the north and west. Wu C.H. et al. [94] selected extreme precipitation indicators in Hubei in the last 10 years and found that extreme precipitation was mainly distributed in the western mountainous region and the southern part of Jianghan Plain. It can be seen that the study area, Hefeng County, is located in the western part of Hubei Province, which is one of the most significant areas of climate change in Hubei Province. In addition, it has been shown that climate change has a significant impact on forest fires and forest soil carbon and nitrogen cycling processes, which in turn affects forest land quality [95]. Therefore, it is particularly important to establish a system of indicators that considers climatic conditions and forest fires. Xiong C.S. et al. [54] considered the inclusion of forest fires in the forest land quality evaluation indicator system and constructed a comprehensive evaluation indicator system for forest land quality in terms of terrain, soil conditions, forest condition, traffic location, and forest fires to evaluate the quality Forests 2021, 12, 325 19 of 25

of forest land. In order to further reveal the influence of climate change and forest fires on forest land quality, in this study, we combined the characteristics of the study area and selected 14 indicators of average annual temperature, average annual precipitation, ≥10 ◦C accumulated temperature, wetness index, elevation, slope, soil type, soil layer thickness, soil texture, soil organic matter, soil pH, land degradation, traffic location, and forest disaster grade from four dimensions—climatic conditions, terrain, soil conditions, and socioeconomics—to construct a forest land quality comprehensive evaluation indicator system. According to the evaluation results, the overall quality of forest land in Hefeng was high, but there were large differences between regions, and the low-quality forest land was mainly distributed in the middle and high mountain regions, and the limiting factors were mainly terrain, climate change, and forest fires, which was consistent with existing studies [96,97]. In the selection of climate change and forest fire indicators, due to the lack of data in the study area, only a few indicators such as average annual temperature, average annual precipitation, ≥10 ◦C accumulated temperature, wetness index, and forest disaster grade were used instead, which are not comprehensive enough for the description of climate change and forest fires on forest land quality and need to be further explored. In addition, forest land quality evaluation is a complex system project, and the evaluation indicator system and evaluation criteria established in this study are subject to further in-depth study and validation due to the limitation of data accessibility. As technology develops, further research could combine remote sensing data and observed data to find more suitable and sensible indicators for evaluating the forest land quality and exploring its spatial difference at the county scale.

4.2. Forest Land Quality Evaluation Model Construction Based on the PSO-TOPSIS Model The quality of the evaluation method directly affects the accuracy of the forest land quality evaluation results. Ozkaya G. and Erdin E. [98] conducted a comparative analysis of forest and air quality in 30 countries using TOPSIS and VIKOR models. In this study, the PSO algorithm was introduced to address the shortcomings of the TOPSIS model, and a PSO-TOPSIS model that can be applied to forest land quality evaluation was designed. For the determination of indicator weights in the TOPSIS model, a nonlinear programming model on weights was established by using the PSO algorithm to determine the weight of each indicator by taking the minimum sum of distances to the optimal and inferior objects as the criterion. This weighting method was highly logical and avoided the subjectivity of determining the weights, making the solved weights more objective. In addition, it has a fairly fast approximation of the optimal solution and can effectively optimize the parameters of the system with a strong local search capability [49]. The TOPSIS model is one of the comprehensive evaluation methods for multiobjective decision making with limited solutions. The calculation of the forest land quality index by an improved TOPSIS model eliminated the influence of different indicator scales after the normalized processing of raw data. It can make full use of the information of the original data, reflect the actual situation objectively, obtain the comprehensive evaluation results of forest land quality, and reveal the key influencing factors of forest land quality. Therefore, the PSO- TOPSIS comprehensive evaluation model constructed in this study not only enriches the evaluation method of forest land quality, but also provides a certain reference for further improving the quality evaluation system, which can provide a scientific basis for formulating and regulating the market transfer price of forest land and compensation for occupied and expropriated forest land. Additionally, the evaluation model constructed in this study could be used as a reference for similar countries and regions; however, forest land quality evaluation is influenced by various factors such as climate, terrain, and soil and has significant inheritance and variability characteristics [51]. Due to the limitation of the research conditions, in this study, we only analyzed the spatial distribution characteristics of the current forest land quality evaluation, which does not apply to the dynamic monitoring analysis of forest land quality. Therefore, further improvement of the Forests 2021, 12, 325 20 of 25

forest land quality evaluation model to improve the evaluation accuracy will be the focus and difficulty of the subsequent research.

4.3. Forest Land Protection Zoning Based on the LISA Based on the LISA of forest land quality index, it can delineate forest land protection zones more scientifically and reasonably. The spatial distribution of forest land quality shows certain spatial aggregation variability characteristics. Specifically, the evaluation indicators of forest land quality will show spatially different or similar changes with in- creasing or decreasing distance [80], which in turn will form certain aggregated distribution characteristics in space. Wei S. C. et al. [99] used a combination of Moran scatter plot and LISA to explore the spatial structural characteristics and aggregation patterns of cropland quality in Guangning County of China using the cropland quality index as a spatial vari- able, and proposed a cropland protection zoning scheme. In this study, we used forest land quality index as a spatial variable and used LISA to explore the spatial aggregation pattern of forest land quality at the village scale, and delineated the forest land protection zones. We proposed a zoning protection strategy, which enriched the methods of forest land protection zoning and provided a new idea for the differentiated protection and fine management of forest land. In addition, the theory of territorial differentiation and the theory of coordinated development of integrated regions are important theoretical bases for zoning studies [100]. Further study of forest land zoning needs to be combined with zoning theory to explore the coordination of population, economy, urban construction, and environment in forest land utilization, to better realize the sustainable use of forest land and the coordinated development of society. How to select and identify the key factors of forest land protection zoning to achieve regional sustainable development, and how to combine the natural ecological and human elements of forest land use for forest land zoning need further exploration.

5. Conclusions Based on the scientific evaluation of forest land quality in Hefeng based on the PSO-TOPSIS model, combining the natural conditions, socioeconomics, and spatial distri- bution characteristics of forest land quality, we used the LISA to explore the law of spatial aggregation of forest land quality at the village scale taking the forest land quality index as a spatial variable. A forest land protection zoning scheme was proposed accordingly. By evaluating the quality of forest land, this study found that the range of the forest land quality index in Hefeng was 0.4091–0.8601, with a mean value of 0.6337, indicating that the overall forest land quality was high, but there were some differences among towns. In addition, there were differences between areas with different grades of forest land quality, mainly the first and second grades. The high-grade forest land was mainly distributed in the central and southeastern low mountain areas of Zouma, Wuli, and Yanzi, and the constraints were mainly terrain and traffic location. The low-grade forest land was mainly gathered in the northwestern high mountains of Zhongying, Taiping, and Rongmei, which was mainly affected by terrain, climate, soil fertility, and forest disasters. Based on the evaluation of forest land quality, using spatial autocorrelation analysis, this study showed that the global spatial autocorrelation index of forest land in Hefeng with village forest land quality as a spatial variable was 0.7562, indicating that forest land quality in the county had a strong similar correlation in spatial distribution. There were five LISA types: high-high (HH), high-low (HL), low-high (LH), low-low (LL), and nonsignificant (NS). The spatial distribution of similarity types HH and LL was more clustered, while the spatial distribution of dissimilarity types HH and LL was generally dispersed. Based on the LISA results of forest land quality, this study proposed a scheme of forest land protection zoning. In response to the spatial aggregation characteristics of forest land quality, forest land protection was divided into three types: key protection zones (HH), active protection zones (HL, LH, and NS (medium)), and general protection zones (LL and NS (low)). The research results showed that the zoning scheme basically coincided with the forest land Forests 2021, 12, 325 21 of 25

quality evaluation results. Combining the characteristics of different protection zones of self-correlated types, corresponding management and protection measures were proposed. This study established the PSO-TOPSIS model to explore new methods of evaluating forest land quality, and the spatial attributes of forest land quality were incorporated into the development of forest land protection zoning schemes, which expanded the means of this type of zoning. The quantity of forest land still needs to be considered in the implementation of forest land zoning protection. Determining how effective management and construction can be implemented in the later stages of forest land protection and how a zoning–scale–management trinity can be actualized in a forest land protection system requires further in-depth research.

Author Contributions: Funding acquisition, Y.Z.; conceptualization, L.W. and Y.Z.; methodology, L.W.; investigation, Q.Z., J.L. and H.G.; writing—original draft preparation, L.W., Y.Z. and Q.L.; writing—review and editing, Q.L. and Y.T. All authors have read and agreed to the published version of the manuscript. Funding: This research was funded by the National Natural Science Foundation of the People’s Republic of China project—Impact of land use evolution on watershed water resources and ecological response in the Jianghan Plain over 50 years (No. 41271534) and the Ministry of Natural Resources of the People’s Republic of China Key Project—Preparation of Technical Specification for Forest Land Grade and Classification (No. 20190722). Institutional Review Board Statement: Not applicable. Informed Consent Statement: Not applicable. Data Availability Statement: No new data were created or analyzed in this study. Data sharing is not applicable to this article. Acknowledgments: We would like to express our deepest gratitude to the Hefeng governmental staff for their help in the research process. We would also like to acknowledge the data supports from the Geospatial Data Cloud Platform (http://www.gscloud.cn/sources/, accessed on 22 April 2020) and the National Earth System Science Data Center Soil subcenter (http://soil.geodata.cn/index.html, accessed on 8 May 2020). Conflicts of Interest: The authors declare no conflict of interest.

References 1. Stave, J.; Oba, G.; Charlotte, S.B.; Mengistu, Z.; Stenseth, N.C. Spatial and temporal woodland patterns along the lower Turkwel River, Kenya. Afr. J. Ecol. 2015, 41, 224–236. [CrossRef] 2. Li, X.; Du, H.; Mao, F.; Zhou, G.; Xing, L.; Liu, T.; Han, N.; Liu, E.; Ge, H.; Liu, Y. Mapping spatiotemporal decisions for sustainable productivity of bamboo forest land. Land Degrad. Dev. 2020, 31.[CrossRef] 3. Redmond, M.D.; Weisberg, P.J.; Cobb, N.S.; Clifford, M.J. Woodland resilience to regional drought: Dominant controls on tree regeneration following overstorey mortality. J. Ecol. 2018, 106, 625–639. [CrossRef] 4. Vander Yacht, A.L.; Barrioz, S.A.; Keyser, P.D.; Harper, C.A.; Buckley, D.S.; Buehler, D.A.; Applegate, R.D. Vegetation response to canopy disturbance and season of burn during oak woodland and savanna restoration in Tennessee. For. Ecol. Manag. 2017, 390, 187–202. [CrossRef] 5. Zaher, H.; Sabir, M.; Benjelloun, H.; Paul-Igor, H. Effect of forest land use change on carbohydrates, physical soil quality and carbon stocks in Moroccan Cedar area. J. Environ. Manag. 2020, 254, 109544. [CrossRef] 6. Dickie, M.; Serrouya, R.; Demars, C.; Cranston, J.; Boutin, S. Evaluating functional recovery of habitat for threatened woodland caribou. Ecosphere 2017, 8, e01936. [CrossRef] 7. Prober, S.M.; Colloff, M.J.; Abel, N.; Crimp, S.; Doherty, M.D.; Dunlop, M.; Eldridge, D.J.; Gorddard, R.; Lavorel, S.; Metcalfe, D.J. Informing climate adaptation pathways in multi-use woodland landscapes using the values-rules-knowledge framework. Agric. Ecosyst. Environ. 2017, 241, 39–53. [CrossRef] 8. Karkuff, S.A. Quantifying Forest Subsidies to Food Webs in Woodland Pools. Master’s Thesis, State University of New York, Syracuse, NY, USA, 2014. 9. Wong, M.H.; Chan, Y.S.G.; Zhang, C.; Ng, W.W. Comparison of pioneer and native woodland species growing on top of an engineered landfill, Hong Kong: Restoration programme. Land Degrad. Dev. 2016, 27, 500–510. [CrossRef] Forests 2021, 12, 325 22 of 25

10. United Nations General Assembly. International Day of Forests; Food and Agriculture Organization of United Nations: Rome, Italy, 2012. 11. State Forestry and Grassland Administration. China Forest Resources Report (2014–2018); China Forestry Press: Beijing, China, 2019. 12. Köhl, M.; Lasco, R.; Cifuentes, M.; Jonsson, Ö.; Korhnen, K.T.; Mundhenk, P.; de Jesus Navar, J.; Stinson, G. Changes in forest production, biomass and carbon: Results from the 2015 UN FAO Global Forest Resource Assessment. For. Ecol. Manag. 2015, 352, 21–34. [CrossRef] 13. Shi, J.H.; Jiang, A.J. Discussions about identifying forestland in plain areas. For. Resour. Manag. 2015, 23–26. 14. Chmura, D.J.; Anderson, P.D.; Howe, G.T.; Harrington, C.A.; Halofsky, J.E.; Peterson, D.L.; Shaw, D.C.; Clair, J.B.S. Forest responses to climate change in the northwestern United States: Ecophysiological foundations for adaptive management. For. Ecol. Manag. 2011, 261, 1121–1142. [CrossRef] 15. Bowman, D.M.J.S.; Murphy, B.P.; Boer, M.M.; Bradstock, R.A.; Cary, G.J. Forest fire management, climate change, and the risk of catastrophic carbon losses. Front. Ecol. Environ. 2013, 11, 66–68. [CrossRef] 16. Drobyshev, B.; Girardin, M.P.; Gauthier, O. Strong gradients in forest sensitivity to climate change revealed by dynamics of forest fire cycles in the post little ice age era. J. Geophys. Res. Biogeosci. 2017, 122, 2605–2616. [CrossRef] 17. Woolford, D.G.; Cao, J.G.; Dean, C.B.; Martell, D.L. characterizing temporal changes in forest fire ignitions: Looking for climate change signals in a region of the Canadian Boreal Forest (2010). Environmetrics 2011, 21, 789. [CrossRef] 18. Wisdom Research Consulting. China Forest Fire Protection Industry Current Research and Future Development Trend Analysis Report (2020–2026); China Market Research Network: Beijing, China, 2020. 19. Su, L.J.; He, Y.J.; Chen, S.Z. Temporal and spatial characteristics and risk analysis of forest fires in China from 1950 to 2010. Sci. Silv. Sin. 2015, 51, 88–96. 20. Bedia, J.; Camia, A.; Moreno, J.M.; Gutierrez Herrera, S. Forest fire danger projections in the Mediterranean using ENSEMBLES regional climate change scenarios. Clim. Chang. 2014, 122, 185–199. [CrossRef] 21. Jian, S.; Joshua, S.F.; Jason, A.; Lynch, K.H.; Yang, G. Climate-driven Exceedance of Total (Wet + dry) Nitrogen (N) + sulfur (S) deposition to forest soil over the conterminous U.S. Earths Future 2017, 5, 560–576. 22. Chen, L.X.; Shi, G.X. Study on improving the quality of forest land of larch plantations. J. Northeast For. Univ. 1998, 26, 6–11. 23. Yu, K.Y.; Liu, J.; Lai, R.W.; Yang, Z.Q.; Wei, Q.G. Chinese fir commercial forests0 forestland productivity in Minjiang watershed based on 3S technologies. J. For. Environ. 2009, 29, 326–331. 24. Zhang, Z.Y.; Liu, P.J.; Tang, X.M. Evaluation of forest land quality based on rough set and C5.0 decision tree. J. Northwest F Univ. Sci. Ed. 2017, 45, 96–102. 25. Chung, I.K. Quantitative forest land productivity survey and the result: Forest land capability classification in South Korea. Jpn. J. For. Environ. 1978, 19, 31–35. 26. Bonilla-Bedoya, S.; Herrera-Machuca, M.A.; Lopez-Ulloa, M.; Vanwalleghem, T. Effects of land use change on soil quality indicators in forest landscapes of the Western Amazon. Soil Sci. 2017, 182. [CrossRef] 27. Lu, F.Z.; Luo, H.J.; Lu, Y. Study on forestland quality indexes and their application. J. For. Environ. 2015, 35, 87–91. 28. Wang, Y.F.; Wei, A.S.; Li, W.; Wen, X.R. Poplar forest land quality evaluation and suitability districts in Si Yang. J. Fujian For. Sci. Technol. 2014, 41, 198–202. 29. Tan, J. Ways and Measures for Improving the Forest Land Productivity in Dongxing City; FAO: Rome, Italy, 2013. 30. Martens, D.A.; Reedy, T.E.; Lewis, D.T. Soil organic carbon content and composition of 130-year crop, pasture and forest land-use managements. Glob. Chang. Biol. 2010, 10, 65–78. [CrossRef] 31. Fuentes-Montemayor, F.; Macgregor Watts, N.A.; Bitenc, P.K.J. Local-scale attributes determine the suitability of woodland creation sites for diptera. J. Appl. Ecol. 2018, 2018, 1173–1184. 32. Tan, K.Y.; Chen, Z.H.; Huang, N.H.; Zhong, H.Z.; Yang, C.Y. Evaluation of intensive use of forest land based on entropy method—A case study of towns in the Pearl River Delta. For. Environ. Sci. 2017, 33, 98–103. 33. Koch, N.E.; Hirokazu, Y.; Kahle, H.-P.; Hasenauer, H.; Centritto, M.; Kjell, N.; Peng, Z.; Weimin, S.; Fuliang, C.; Shirong, L.; et al. Classification of Integrated Quality of Chinese Woodland Using Fuzzy Mathemtics. In Proceedings of the International Conference on Sustainable Forest Management—Forest Science Forum, Beijing, China, 13–16 October 2012. 34. Goushegir, S.Z.; Feghhi, J.; Mohajer, M.R.M.; Makhdoum, M. Criteria and Indicators of monitoring the sustainable wood production and forest conservation using AHP (Case study: Kheyrud educational and research forest). Afr. J. Agric. Res. 2009, 4, 1041–1048. 35. Chen, Z.; Yang, C.; Deng, D.; Zhihua, L.I. Analysis of influencing factors and model prediction of forest coverage in Guangdong Province: Based on grey correlation analysis and GM (1,1) model. For. Environ. Sci. 2017, 33, 101–106. [CrossRef] 36. Ye, J. Multicriteria fuzzy decision-making method using entropy weights-based correlation coefficients of interval-valued intuitionistic fuzzy sets. Appl. Math. Model. 2010, 34, 3864–3870. [CrossRef] 37. Xia, X.; Sun, Y.; Wu, K.; Jiang, Q. Optimization of a straw ring-die briquetting process combined analytic hierarchy process and grey correlation analysis method. Fuel Process. Technol. 2016, 152, 303–309. [CrossRef] 38. Wang, Z.; Li, K.W.; Xu, J. A Mathematical programming approach to multi-attribute decision making with interval-valued intuitionistic fuzzy assessment information. Expert Syst. Appl. 2011, 38, 12462–12469. [CrossRef] Forests 2021, 12, 325 23 of 25

39. Kumar, V.S. Analytic hierarchy process: An overview of applications. Eur. J. Oper. Res. 2006, 48, 77–80. 40. Awad, G.A.; Sultan, E.I.; Ahmad, N.; Ithnan, N.; Beg, A.H. Multi-objectives model to process security risk assessment based on AHP-PSO. Mod. Appl. Sci. 2011, 5, 3. [CrossRef] 41. Prasannavenkatesan, S.; Kumanan, S. Multi-objective supply chain sourcing strategy design under risk using PSO and simulation. Int. J. Adv. Manuf. Technol. 2012, 61, 325–337. [CrossRef] 42. Yazdanbakhsh; Mohammadi, J. Evaluation of Land Use in Areas of Golestan City Using L.Q. and TOPSIS Models. Int. J. Ecol. Dev. 2015, 30, 43–54. 43. Mukherjee, A.B.; Krishna, A.P.; Patel, N. Application of Remote Sensing Technology, GIS and AHP-TOPSIS Model to Quantify Urban Landscape Vulnerability to Land Use Transformation; Springer: Berlin/Heidelberg, Germany, 2018. 44. Han, G.Y.; Chen, W.; Feng, Z.J. Selection of enterprise’s cooperative innovationpartners-based on PSO fixed weight and ameliorated TOPSIS method. Sci. Res. Manag. 2014, 35, 119–126. 45. Bagherzadeh, A.; Gholizadeh, A. Parametric-based neural networks and TOPSIS modeling in land suitability evaluation for Alfalfa production using GIS. Model. Earth Syst. Environ. 2017, 3, 2. [CrossRef] 46. Min, C.; Min, W.; Haidong, Y. Evaluation of sustainable urban land use based on weighted TOPSIS method: A case study of Chengdu City. Iop Conf. 2019, 227, 62026. 47. Nilsson, H.; Nordstrm, E.-V.; Karin, H. decision support for participatory forest planning using AHP and TOPSIS. Forests 2016, 7, 100. [CrossRef] 48. Cai, X.; Jiang, Y. Evolution of space-time pattern of chinese forest ecological security and its obstacle factor diagnosis. Stat. Decis. 2019, 35, 96–100. 49. Zhang, Z.D.; Liu, D.; Zhang, H.R.; Li, G.X. Irrigation water use efficiency evaluation based on combination weighting of PSO-AHP and rough set theory. Water Sav. Irrig. 2018, 278, 64–72. 50. Hinsley, S.A.; Hill, R.A.; Bellamy, D.L.A.; Gaveaup, E. Quantifying woodland structure and habitat quality for birds using airborne laser scanning. Funct. Ecol. 2002, 16, 851–857. [CrossRef] 51. Ford, M.M.; Zamora, D.S.; Current, D.; Magner, J.; Wyatt, G.; Walter, W.D.; Vaughan, S. Impact of managed woodland grazing on forage quantity, quality and livestock performance: The potential for silvopasture in Central Minnesota, USA. Agrofor. Syst. 2019, 93, 67–79. [CrossRef] 52. Fu, X.; Wang, X.J.; Ma, W.; Cao, L.; Li, L.W.; Huang, G.S.; Chen, X.Y.; Dang, Y.F. Forestland site quality and potential productivity evaluation in Daxing’anling forest region of inner Mongolia. J. Shenyang Agric. Univ. 2019, 50, 99–108. 53. Xing, S.H.; Wei, H. Calculation and division of regional forestry land productivity based on GIS. Mt. Res. 2006, 24, 473–479. 54. Xiong, C.S.; Tan, Y. Quality Evaluation and protection zoning of forest land based on local spatial autocorrelation. J. Nat. Resour. 2016, 31, 457–467. 55. Zhang, P.; Shao, G.; Zhao, G.; Le Master, D.C.; Parker, G.R.; Dunn, J.B. Dunning Ecology-China’s Forest Policy for the 21st Century. Science 2000, 288, 2135–2136. [CrossRef] 56. Chen, Y.Q.; Zhang, Z.J.; Guo, X.D.; Lu, C.Y.; Wang, X.F. Spatial-temporal analysis on ecological land changes in the key ecological functional areas in China. China Land Sci. 2018, 32, 19–26. 57. Zhang, J.C.; Wang, Y.H. Simulation of village-level population distribution based on land use: A case study of Hefeng County in Hubei Province. J. Geo-Inf. Sci. 2014, 16, 435–442. 58. Zhang, H.; Shi, H.N.; Zhang, Q.L. Study on the characteristics of forest fire in Central South of China based on multivariate analysis. J. Temp. For. Res. 2018, 1, 27–34. 59. Nabiollahi, K.; Taghizadeh-Mehrjardi, R.; Kerry, R.; Moradian, S. Assessment of soil quality indices for salt-affected agricultural land in Kurdistan Province, Iran. Ecol. Indic. 2017, 83, 482–494. [CrossRef] 60. Nunes, A.L.P.; Bartz, M.L.; Mello, I.; Bortoluzzi, J.; Roloff, G.; Fuentes Llanillo, R.; Canalli, L.; Wandscheer, C.A.R.; Ralisch, R. No-till system participatory quality index in land management quality assessment in Brazil. Eur. J. Soil Sci. 2020, 71, 974–987. [CrossRef] 61. Román-Figueroa, C.; Padilla, R.; Uribe, J.; Paneque, M. Land suitability assessment for Camelina (Camelina Sativa L.) development in Chile. Sustainability 2017, 9, 154. [CrossRef] 62. Díaz, I.; Mello, A.L.; Salhi, M.; Spinetti, M.; Bessonart, M.; Achkar, M. Multiscalar land suitability assessment for aquaculture production in Uruguay. Aquac. Res. 2017, 48, 3052–3065. [CrossRef] 63. Cotrufo, M.F.; Alberti, G.; Inglima, I.; Marjanovi´c,H.; Lecain, D.; Zaldei, A.; Peressotti, A.; Miglietta, F. Decreased Summer Drought Affects Plant Productivity and Soil Carbon Dynamics in a Mediterranean Woodland. Biogeosciences 2011, 8, 2729–2739. [CrossRef] 64. Li, B.G. Quantification of soil changes and their processe. Adv. Soil Sci. 1995, 23, 33–42. 65. Caulfield, M.E.; Fonte, S.J.; Tittonell, P.; Vanek, S.J.; Groot, J.C.J. Intercommunity and on-farm asymmetric organic matter allocation patterns drive soil fertility gradients in a rural andean landscape. Land Degrad. Dev. 2020, 31.[CrossRef] 66. Santoso, N.A.; Iqbal, M.; Ekawati, G.; Firdaus, R. Study of PH and magnetic susceptibility to fertility rate of agricultural soil around Institut Teknologi Sumatera, Lampung, Indonesia. Iop Conf. 2019, 258, 012001. [CrossRef] 67. Schares, G.; Jutras, C.; Bärwald, A.; Basso, W.; Maksimov, A.; Schares, S.; Tuschy, M.; Conraths, F.J.; Brodeur, V. Besnoitia Tarandi in Canadian woodland caribou–isolation, characterization and suitability for serological tests. Int. J. Parasitol. Parasites Wildl. Sciverse Sci. 2019, 8, 1–9. [CrossRef] Forests 2021, 12, 325 24 of 25

68. National Forestry Administration. Technical Regulations for Defining Forest Land Border in Forest Land Planning on Protection and Utilization; China Standard Press: Beijing, China, 2011. 69. State Administration for Maket Regulation; Standardization Administration. Technical Regulations for Continuous Forest Inventory; China Standard Press: Beijing, China, 2020. 70. General Administration of Quality Supervision, Inspection and Quarantine of the People’s Republic of China; Standardisation Administration of the People’s Republic of China. Regulation for Gradation on Agriculture Land Qaulity; China Standard Press: Beijing, China, 2012. 71. General Administration of Quality Supervision, Inspection and Quarantine of the People’s Republic of China; Standardisation Administration of the People’s Republic of China. Cultivated Land Quality Grade; China Standard Press: Beijing, China, 2016. 72. Kennedy, J.; Eberhart, R. Particle Swarm Optimization. In Proceedings of the ICNN 95-International Conference on Neural Networks, Madrid, Spain, 6–9 August 2002. 73. Rossum, G.V.; Drake, F.L. Python 3 Reference Manual. Dep. Comput. Sci. Cs 1995, 111, 1–52. 74. Elaalem, M.; Comber, A.; Fisher, P. Land Evaluation Techniques Comparing Fuzzy AHP with TOPSIS Methods. In Proceedings of the Agile Conference on Geographic Information Science: “Geospatial Thinking”, Guimarães, Portugal, 11–14 May 2010. 75. Jiang, C.; Zhao, W.; Shan, X.; Yixue, L.I.; Shuxuan, W.U. Evaluation and obstacle analysis of urban land use system based on TOPSIS-PSR model. J. Hubei Univ. Natl. 2018, 36, 475–480. 76. Jozi, S.A.; Majd, N.M. Ecological land capability evaluation of Dehloran County in order to ecotourism development. J. Indian Soc. Remote Sens. 2015, 43, 571–581. [CrossRef] 77. Luo, W.B.; Tong, Z. Performance Evaluation of Rural Land Consolidation and Analysis of Spacial Variation Based on “PSR” Framework and “TOPSIS” Model. In Proceedings of the International Conference on Information Management, Ankara, Turkey, 25–28 October 2012. 78. Daniel, Z. Sui Tobler’s first law of geography: A big idea for a small world? Ann. Assoc. Am. Geogr. 2003, 94, 269–277. 79. Zhu, J.; Shi, X. Analysis of spatial autocorrelation patterns of land use and influence factors in loess hilly region—A case study of Changhe Basin of Jincheng City. Res. Soil Water Conserv. 2018, 25, 234–241. 80. Xiao, G.; Hu, Y.; Li, N.; Yang, D. Spatial autocorrelation analysis of monitoring data of heavy metals in rice in China. Food Control 2018, 89, 32–37. [CrossRef] 81. Li, J.; He, J.; Liu, Y.; Wang, D.; Rafay, L.; Chen, C.; Hong, T.; Fan, H.; Lin, W. Can spatial autocorrelation analysis of multi-scale damaged vegetation in the Wenchuan earthquake-affected area, Southwest China. Forests 2019, 10, 195. [CrossRef] 82. Anselin, L. Local Indicator of Spatial Association-LISA. Geogr. Anal. 1995, 27, 93–115. [CrossRef] 83. Amarasinghe, U.; Samad, M.; Anputhas, M. Spatial clustering of rural poverty and food insecurity in Sri Lanka. Food Policy 2005, 30, 493–509. [CrossRef] 84. Deng, T.; Wang, R.; Jiang, T.; Huang, J.L.; Fang, X.; Liu, R. Simulation and projection of future climate change in Hubei Province using high-resolution regional climate model. Resour. Environ. Yangtze Basin 2017, 26, 937–944. 85. Chen, Z.H. Horizontal and vertical distribution of forest fire disasters in Western Hubei and its corrleation with topographic climate. Geogr. Res. 1992, 11, 98–100. 86. Wang, Y.Y.; Zhao, M.W.; Zhao, K.L.; Ye, Z.Q. Effects of altitude on PH value and available nutrients in Chinese Hickory Orchards. Mod. Agric. Sci. Technol. 2012, 17, 224–231. 87. Chen, Y.G. Reconstructing the mathematical process of spatial autocorrelation based on Moran’s statistics. Geogr. Res. 2009, 28, 1449–1463. 88. Bei, H.L.; Wu, C.F.; Feng, K.; Liu, T.T. Regional disparity and dynamic evolution of land economic density—Evidence from the Yangtze River Delta area. J. Nat. Resour. 2009, 24, 1952–1962. 89. Mo, K. The Study on Quality Assessment Indicator System of Timber Forest and Its Methods at Subcompartment Level. Ph.D. Thesis, Beijing Forestry University, Beijing, China, 2012. 90. Deng, W.Q. Evaluation of Qaulity of Woodland of Changsha City. Master’s Thesis, Central South University of Forestry and Technology, Changsha, China, 2013. 91. Wang, H.B. The Study and Practice of Forestland Modern Management Mode and the Key Issues in China. Ph.D. Thesis, Beijing Forestry University, Beijing, China, 2011. 92. Zhang, H.R.; Lei, X.D.; Li, F.R. Research progress and prospects of forest management science in China. Sci. Silv. Sin. 2020, 56, 130–142. 93. Gao, X.; Li, X.G.C.; Yin, C.J. Empirical analysis of extreme climate events and its impact on climate yield of rice: A case study of Hubei Province. J. China Agric. Univ. 2017, 22, 153–162. 94. Wu, C.H.; Wang, X.L.; You, L.M.; Niu, B.; Wang, S.S.; Li, Y.L. Spatial and temporal characteristics of severe precipitation in Hubei province during the past 10 years and main weather conceptual model. Torrential Rain Disaster 2013, 32, 113–119. 95. Mukhopadhyay, D. Impact of climate change on forest ecosystem and forest fire in India. IOP Conf. 2009, 6, 382027. [CrossRef] 96. Li, X.D.; Du, Y.; Wu, S.J.; Sun, J.Y.; Feng, Q.; Song, Y.J. Evolvement and effects of climate-productivity on climate change in Hubei Province. Syst. Sci. Compr. Stud. Agric. 2009, 25, 294–298. 97. Yuan, M.X.; Zou, L.; Lin, A.W.; Zhu, H.J. Analyzing dynamic vegetation change and response to climatic factors in Hubei Province, China. Acta Ecol. Sin. 2016, 36, 5315–5323. Forests 2021, 12, 325 25 of 25

98. Ozkaya, G.; Erdin, E. Evaluation of sustainable forest and air quality management and the current situation in europe through operation research methods. Sustainability 2020, 12, 10588. [CrossRef] 99. Wei, S.C.; Xiong, C.S.; Luan, Q.L.; Hu, Y.M. Protection zoning of arable land quality index based on local spatial autocorrelation. Trans. Chin. Soc. Agric. Eng. 2014, 30, 249–256. 100. Yang, Y.; Ren, Z.Y.; Fan, X.S. Land use comprehensive evaluation and regionalization in Zhongyuan urban agglomeration. Econ. Geogr. 2017, 9, 179–186.