2016 3rd International Conference on Engineering Technology and Application (ICETA 2016) ISBN: 978-1-60595-383-0

Ecological Stress and Analysis of Ecological Effect in Area

Xuyang Yao & Jiujun Lv* Academy of Environmental Sciences, , Liaoning,

ABSTRACT: Estuarine wetland degradation of Liao River caused by human activities has gradually caught people’s attention. It has left great influence on structure, quality and functions of natural ecological system. This thesis took Panjin area as the research object and applied remote sensing and GIS technology to analyze structure, quality, functions and impact factors of the ecological system in Panjin area. The results show climate warming is an important reason for the influence that causes changes in wetland ecological system of Panjin area. To a cer- tain degree, development of economy, agriculture, and industry has also impacted the changes in structure, qual- ity, and functions of ecological system in Panjin area. Moreover, nature and human factors have played non-ignorable roles in ecological effect and anthropogenic factor has more obvious effect.

Keywords: Panjin area; stress factor; ecological effect

1 INTRODUCTION tigation, social economic statistics, and data of remote sensing, this research combines the influence from Wetland is natural complex formed by interaction natural stress factors and discusses the interactions between land and water. It is one of the most im- among ecological stress factors, wetland distribution portant environment capitals for human, containing pattern, wetland ecological system quality, wetland strong production and service functions. [1] Wetland ecological system service functions, ecological system ecological system is one the ecological systems which structure, and ecological environment by investigating are facing the most serious threat in the world [2]. Un- the influence from man-made stress. It analyzes the der influence from natural factors and human activities, comprehensive ecological effect of the ecological large-scale wetlands have been developed into farm- stress factors in wetland area, aiming to effectively lands with weakened functions. The loss in natural regulate human’s development activities in estuarine wetland is really serious. [3] As coastal wetlands have wetland areas and provide technical support for scien- centralized distribution and various types, corre- tific management. sponding artificial disturbance is strong which has become a hot spot for research on landscape structures of coastal wetland [4-11]. With disturbance from stress 2 OVERVIEW OF RESEARCH AREA factors, structures and functions of coastal wetland have suffered acute changes. Panjin lies in the heart- Panjin locates in the central part of Liaoning Province. land of downstream delta of Liao River. Therefore, It is in the downstream of Liao River and lies on the analysis of the situation, functions, and pressure of coast of Bohai. The geographical coordinates of Pan- wetland ecological system in Panjin can reveal the jin are 121°33′~122°28Eand 40°41′~41°28′N. It is quality, structure, and function conditions of regional mainly composed of wetland, farmland, and urban ecological system and the coupling relation between landscape. The climate there belongs to semi-humid wetland ecological system and social economic de- monsoon-type climate in continental warm tempera- velopment, so as to provide strategic support for eco- ture zone. logical environment protection. Based on field inves-

*Corresponding author: [email protected]

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3 RESEARCH METHOD 3.2.2 Assessment on quality of ecological system Assessment on ecological system quality mainly used 3.1 Selection of stress factors the types, distribution, and surface parameters of Pan- jin in 2010 obtained by remote-sensing interpretation; The remote-sensing data applied in this research came and combined the long-term monitoring data of eco- from “Remote-Sensing Investigation and Assessment logical system or environment position monitoring on Ten-Year Changes of National Ecological Envi- station. This research applied vegetation coverage ronment (2000-2010)—Remote-Sensing Investigation index in unit area to evaluate the ecological system and Assessment on Ten-Year Changes of Ecological quality in each town of Panjin. The method to calcu- Environment in Liaoning Province” program. The data late vegetation coverage is as follows: required in investigation and analysis of natural stress factors of Panjin was mainly obtained by yearbook NDVI- NDVIsoil F = reference and department docking. The temperature c NDVIveg- NDVI soil and rainfall of Panjin in recent 35 years were used to analyze the influence that two natural stress factors, Among which, Fc refers to vegetation coverage; temperature and rainfall, have left on estuarine eco- NDVI shall be calculated through the emissivity of [13-14] logical system . remote-sensing image near-infrared band and of red Man-made stress research was to analyze and in- band; NDVIveg refers to the NDVI value of pure vege- vestigate influence factors, such as human activity tation pixel; and NDVIsoil refers to the NDVI value of intensity, economic construction activities, resource complete non-vegetation coverage pixel. development activities, and agricultural production, and combine field investigation, in order to com- 3.2.3 Assessment on functions of ecological system prehensively decide the analysis indexed selected for service each factor, such as population density, traffic network Based on remote-sensing and ground investigation construction, urban development, and development data, combine the long-term monitoring data of na- pattern of water and electricity, collect and analyze the tional ecological system observation and research influence that man-made stress factors have left on [15-16] network. Apply the assessment model of ecological ecological system . See Table 1 for the assess- system service functions to assess function status and ment indexes for man-made stress factors. spatial features of ecological system, such as biologi- cal diversity maintenance, soil conservation, water Table 1. Assessment indicator system of human stress in ecological system. conservation, wind prevention and sand fixation, car- bon fixation, and product service functions. Calculate First-class Second-class Third-class indicator the ecological system service functions in each town indicator indicator of Panjin, and conduct non-dimensional processing. Population density Urban population density 3.2.4 Calculation of human stress factors GDP density The calculation formula and parameter description of Social economic Density of value-added of different indicators is shown in Table 2. activity intensity primary industry Human Density of value-added of activity secondary industry 3.3 Landscape mapping and data analysis intensity Density of value-added of tertiary industry Landsat TM/ETM remote-sensing image data of 2012 was used to process atmospheric correction, ortho- Development and Construction land construction activity graphic correction, and geometric correction. Based intensity intensity on constructed landscape classification, classified Agricultural activity Usage amount of chemi- interpretation of remote-sensing image was given after intensity cal fertilizer in unit area checking time phase, cloud cover, wave band, noise, deformation, stripe, and pixel size of image. SPSS18.0 software and ArcGIS software were applied in data 3.2 Calculation method of each indicator processing to analyze changes in ecological system structure. In the meantime, CANOCO4.5 software was 3.2.1 Assessment on structure of ecological system used to make grey correlation degree analysis, taking Assessment on ecological system structure mainly construction land index, population density, urban used the types and distribution of ecological systems population density, GDP density, value-added density of Panjin in 2010 obtained by remote-sensing inter- of primary industry, value-added density of secondary pretation. This research applied area of natural eco- industry, value-added density of tertiary industry, and logical system to evaluate the ecological system chemical fertilizer utilizing intensity in each town of structures in each town of Panjin. Panjin as the independent variables while taking area

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Table 2. Calculation method for assessment on human stress in ecological system. Name of indicator Calculation formula Parameter description

P ×10000 PDi,t refers to the population density of No.i town in No.t year (population/km²); Pi,t Population density PD = ,ti refers to the total population of No.i town at the end of No.6 years (10,000); A ,ti A i i refers to the national territorial area of No.i town (km²)

UPDi,t refers to the population density of No.i town in No.t year (population/km²); Urban population UP ,ti ×10000 UPD ,ti = UPi,t refers to the total population of permanent residents of No.i town at the end of density Ai No.t year (10,000); Ai refers to the national territorial area of No.i town (km²)

GDPi, t GDP i,t refers to the GDP density of No.i town in No.t year (unit: 10,000 yuan/km²); GDP density DGDP = i, t UPi,t refers to the GDP of No.i town in No.t year (10,000) Ai USLIi,t refers to the construction land utilizing index of No.i town in No.t year (％); Construction land USLi, t USLI i, t = × 100% USLi,t refers to the construction land area of No.i town in No.t year (km²); Ai refers intensity Ai to the national territorial area of No.i town (km²) CFUIi,t refers to the utilizing intensity of chemical fertilizer of No.i town in No.t Usage amount of CFU ,ti year (ton/km²). Data shall be correct to two digits after decimal point; CFUi,t refers chemical fertilizer in CFUI = ,ti A to the usage amount of chemical fertilizer of No.i town in No.t year (ton); Ai refers unit area i to the national territorial area of No.i town (km²) (1) Similar to the methods of collecting and calculating GDP data, collect and cal- culate the value-added data of primary industry for comparable price of each town Density of value-added over the years; (2) Calculate the value-added of primary industry for comparable

of primary industry price of unit national territorial area of teach town according to the value-added of primary industry and national territorial area for comparable price of each town over the years (10,000 yuan/km²) (1) Similar to the methods of collecting and calculating GDP data, collect and cal- culate the value-added data of secondary industry for comparable price of each town Density of value-added over the years; (2) Calculate the value-added of secondary industry for comparable

of secondary industry price of unit national territorial area of teach town according to the value-added of secondary industry and national territorial area for comparable price of each town over the years (10,000 yuan/km²) (1) Similar to the methods of collecting and calculating GDP data, collect and cal- culate the value-added data of tertiary industry for comparable price of each town Density of value-added over the years; (2) Calculate the value-added of tertiary industry for comparable

of tertiary industry price of unit national territorial area of teach town according to the value-added of tertiary industry and national territorial area for comparable price of each town over the years (10,000 yuan/km²)

ratio of natural ecological system, ecological system service function in unit area, and vegetation coverage in unit area as the dependent variables [17].

4 ANALYSIS

4.1 Comprehensive investigation and analysis of natural stress factors According to arrangement and calculation of the me- teorological data of Panjin in 35 years, it can be con- Figure 1. Diagram of the annual average temperature and cluded that the average temperature of Panjin in sev- annual precipitation of Panjin from 1978 to 2012. eral years was 9.27℃ with a total sum of annual av- erage rainfall of 633.73mm. The maximum value of According to the annual average temperatures of annual average temperature was 10.4℃ which ap- Panjin from 1978 to 2012 and the average temperature peared in 2004. The minimum value of annual average data in several years, the annual average temperature temperature was 8℃ that appeared in 1985. The departure diagram of Panjin in recent 35 years was maximum value of annual average rainfall was drawn. It can be seen from Figure 2 that most annual 1081.7mm which appeared in 2010. The minimum average temperatures of Panjin from 1978 to 1990 are value of annual average rainfall was 361.4mm which lower than the average value of several years. Howev- appeared in 1980. See Figure 1 for the average tem- er, the annual average temperature is higher than the perature and annual rainfall of Panjin in each year. average value of several years in general since 1990s,

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reflecting the trend of climate change in Panjin. increase or progressive decrease law can be found. Standard deviation computational formula was used to calculate the standard deviation of the annual rainfall of Panjin in recent 35 years and the value was 163.44 which can reflect the fluctuation range of annual rain- fall in Panjin. In years with extreme drought or mois- ture, the influence left on wetland ecological system was great.

4.2 Comprehensive investigation and analysis of human stress factors Figure 2. Diagram of annual average temperature departure of Panjin from 1978 to 2012. Each man-made stress factor index was calculated and the results show that the population density of Panjin SPSS software was used for regression analysis of in 2012 was 360.46; the urban population density was the annual average temperature departure of each year 246.37; the value-added density of primary industry in Panjin. It can be seen from Figure3 that the annual was 303.55; the GDP density was 2537.96; the val- average temperature in Panjin was turning warmer. ue-added density of secondary industry was 1394.50; From 2000 to 2010, the average temperature got high- and the value-added density of tertiary industry was er by 0.447℃. According to this development trend, it 839.91. It can be seen from Figure 5 that the population is estimated that the annual average temperature of density within city and the urban population density of Panjin will reach 10.51℃ and will further accelerate Panjin were higher in the center and lower in the sur- the moisture evaporation rate and evapotranspiration rounding area, among which areas with higher density of water body. Thus, great influence may be brought were mainly distributed in Shuangtaizi, Xinglongtai, to the wetland ecological system of Panjin. and Dawa Town. However, the population density and the urban population density in the southwest of Pan- jin were relatively lower with low human activity intensity. Areas with higher GDP density and val- ue-added density of secondary industry in Panjin were mainly distributed in Shuangtaizi, Xinglongtai, Dawa Town, and Liaobin Coastal Economic Zone. Areas with lower GDP density were mainly distributed in the northwest of Panjin. Towns with lower value-added density of secondary industry were mainly distributed Figure 3. Change trend of annual average temperature depar- in Dongfeng Town, Zhaoquanhe Town, and Erjiegou ture of Panjin from 1978 to 2012. Town. Towns with higher value-added density of primary industry in Panjin were mainly distributed in Dawa Town, Xi’an Town, Erjiegou Town, and Tian- zhuangtai Town. Towns with lower value-added den- sity of primary industry were mainly distributed in the north and the northwest of Panjin. Areas with higher value-added density of tertiary industry in Panjin were Shuangtaizi , Xinglongtai District, Dawa Town, Tianjia Town, and Tianzhuangtai Town. Area with lower value-added density of tertiary industry was Zhaoquanhe Town. Areas with higher construction land index in Panjin were Shuangtaizi District and Figure 4. Diagram of annual rainfall departure of Panjin from Dawa Town. Towns with lower construction land 1978 to 2012. index were mainly distributed in Shaling Town, Baqiangzi Town, Yangquanzi Town, Dongguo Town, According to the annual rainfall data from 1978 to and Zhaoquanhe Town. Towns with higher chemical 2012 in Panjin and the average rainfall data of several fertilizer utilizing intensity in Panjin were Tianjia years, the annual rainfall departure diagram of Panjin Town, Xinli Town, Guchengzi Town, and Xi’an Town. in recent 35 years was drawn. It can be seen from Town with lower chemical fertilizer utilizing intensity Figure 4 that he annual rainfall of Panjin had major were mainly distributed in Yangquanzi Town, fluctuations from 1978 to 1990. No obvious pressive Dongguo Town, and Zhaoquanhe Town.

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town in Panjin, so as to confirm the contribution that stress factors have made in structure, quality, and service function of estuarine wetland ecological sys- tem in Panjin; and to evaluate the comprehensive ef- fect. ArcGIS software was used to calculate the area ra- tio of natural ecological system in each town of Panjin, the ecological system service function of Panjin in unit area; and the vegetation coverage degree in unit area (See Table 3). It can be seen from the table that a. Population density b. Urban population density each index was comparatively high in Yangquanzi Town, Zhaoquanhe Town, Liaobin Economic Zone, and Dongguo Town. Estuarine reed wetland has been in continuous recovery which will be beneficial for estuarine wetland ecological structure conservation and function recovery. However, there were few changes in the other towns. Dongsheng Town has established modern agricultural technology develop- ment zone to develop modernized livestock breeding; and has built standardized bases for planting produc- tion, seeding, and breeding. To develop featured agri- c. Spatial distribution of GDP d. Density of value-added of culture, Dongguo Town has made great effort to de- primary industry velop river crab culturing bases in coastal areas. Lo- cating in the east of Panjin, Hujia Town and Taiping Two has established basic farmland construction areas and part reed fields have been changed into rice field. Area ratio of natural ecological system in Panjin, ecological system service function in unit area, and vegetation coverage degree in unit area were selected as the dependent variables while construction land index, population density, urban population density, GDP density, value-added density of primary industry, value-added density of secondary industry, val- ue-added density of tertiary industry, and chemical e. Density of value-added f. Density of value-added fertilizer utilizing intensity in each town of Panjin of secondary industry of tertiary industry were selected as the independent variables to make grey correlation degree analysis. Higher grey correla- tion degree refers to greater influence that independent variable array has on dependent variables. It can be seen from Table 4 that the order of man-made stress factors which can affect the area ratio of natural ecological system is GDP density > value-added density of tertiary industry > chemical fertilizer utilizing intensity > construction land index > urban population density > population density > val-

ue-added density of primary industry > value-added g. Construction land utilizing h. Utilizing intensity of index of each town chemical fertilizer of each density of secondary industry. The order of man-made town stress factors which can affect ecological system ser- vice function is chemical fertilizer utilizing intensity > Figure 5. Each human stress factor indicator of each town in urban population density > value-added density of Panjin. secondary industry > population density > GDP den- sity > value-added density of primary industry > val- 4.3 Comprehensive ecological effect due to estuarine ue-added density of tertiary industry > construction ecological stress land index. The order of man-made stress factors which can affect vegetation coverage rate is chemical Area ratio of natural ecological system, ecological fertilizer utilizing intensity > population density > system service function, and vegetation coverage were value-added density of secondary industry > val- selected as the representative indexes for assessment ue-added density of primary industry > urban popula- on the changes in ecological system structure of each tion density > construction land index > value-added

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Table 3. Index table of structure, quality and service functions of ecological system of each town in Panjin. Area ratio of natural ecological Vegetation coverage in unit Service functions of ecological Villages and towns system area system in unit area Gaosheng Town 4.66% 0.85% 117.23 Desheng Town 9.70% 0.88% 161.27 Hujia Town 16.52% 0.92% 143.22 Taiping Town 11.47% 0.86% 144.12 Tianshui Town 15.69% 1.29% 74.19 Yangquanzi Town 76.91% 0.74% 172.53 Shixin Town 5.74% 0.79% 153.87 Dongguo Town 76.30% 0.75% 175.75 Chenjia Town 5.07% 0.96% 100.79 Shuangtaizi District 8.14% 1.01% 107.36 Xinglongtai District 16.95% 0.84% 152.61 Wujia Town 3.72% 1.07% 129.69 Shaling Town 2.82% 1.00% 144.59 Guchengzi Town 2.49% 1.21% 144.36 Baqiangzi Town 0.86% 0.96% 40.75 Xinxing Town 20.42% 0.87% 138.93 Zhaoquanhe Town 65.93% 0.78% 157.21 Xinkai Town 0.70% 0.99% 135.68 Xinli Town 0.31% 0.94% 127.45 Dongfeng Town 2.18% 1.14% 136.58 Tianjia Town 0.42% 0.89% 115.09 Qingshui Town 0.52% 0.93% 165.97 Dawa Town 0.86% 0.88% 135.40 Wangjia Town 13.23% 1.31% 104.55 Tangjia Town 11.17% 1.57% 40.75 Xi’an Town 2.50% 1.19% 117.63 Ping’an Town 13.36% 0.90% 159.68 Tianzhuangtai Town 6.76% 1.22% 133.95 Erjiegou Town 13.04% 1.61% 37.49 Liaobin Coastal Economic 33.50% 1.03% 101.90 Zone District

Table 4. Grey relational analysis of ecological effect in Panjin. Index arear ESev Pev Construction land utilizing index 0.8258 0.7127 0.809 Population density 0.8067 0.7666 0.8664 Urban population density 0.8228 0.783 0.839 GDP density 0.8816 0.7498 0.7567 Density of value-added of primary industry 0.803 0.7372 0.8403 Density of value-added of secondary industry 0.7488 0.7777 0.8657 Density of value-added of tertiary industry 0.8766 0.7298 0.7845 density of tertiary industry > GDP density. land ecological recovery and protection while offering technical support for effective regulation on human development activities and scientific management in 5 CONCLUSIONS AND DISCUSSION estuarine wetland area. Urbanization is the main reason that has caused Based on history evolution process of estuarine wet- changes in the ecological system structure in Panjin land and analysis of important degeneration factors while economic development, especially development according to estuarine wetland ecological degenera- of tertiary industry, has brought acute changes in eco- tion and serious pollution problems in Panjin, this logical system pattern and left influence on the pattern thesis started with prediction of future wetland distri- variation in coastal area. Moreover, in order to devel- bution structure and discussed evolution pattern and op agriculture, relieve increasingly strained land and potential ecological risk of estuarine wetland driven water resources, and bring significant impact on agri- by estuarine wetland policy, economic factors and cultural development, Panjin has continuously ex- social factors. Also, it made precautionary analysis of tended the area to raise crabs in paddy field and de- the ecological safety of future estuarine wetland; and velop fish-farming; and has played an important role constructed ecological safety protection system for in changing the ecological structure of Panjin based on estuarine wetland, aiming to provide basis for related significant improvement of industrial management research on comprehensive treatment of estuarine level in agriculture. Population density in estuarine water pollution and technical research subject of wet- wetland area is high while the economic activities are

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