NIGERIA National Forest (Carbon) Inventory WITH TECHNICAL SUPPORT OF: Cover Illustration: ©Lorenzo Catena NIGERIA National Forest (Carbon) Inventory FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS Abuja, 2020 REQUIRED CITATION FAO. 2020. Nigeria - National forest (carbon) inventory. Abuja. https://doi.org/10.4060/cb1328en The designations employed and the presentation of material in this information product do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations (FAO) concerning the legal or development status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. The mention of specific companies or products of manufacturers, whether or not these have been patented, does not imply that these have been endorsed or recommended by FAO in preference to others of a similar nature that are not mentioned. 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Users wishing to reuse material from this work that is attributed to a third party, such as tables, figures or images, are responsible for determining whether permission is needed for that reuse and for obtaining permission from the copyright holder. The risk of claims resulting from infringement of any third-party-owned component in the work rests solely with the user. Sales, rights and licensing. FAO information products are available on the FAO website (www.fao.org/publications) and can be purchased through [email protected]. Requests for commercial use should be submitted via: www.fao. org/contact-us/licence-request. Queries regarding rights and licensing should be submitted to: [email protected]. Contents Acronyms and abbreviations VI 2.7.4 Modelling height-diameter 16 relationship Executive summary IX 2.7.5 Estimation of aboveground 16 1. Introduction 1 biomass 2.7.6 Estimation of belowground 16 1.1 General background 1 biomass 1.2 Brief history of national forest 1 2.7.7 Estimation of biomass for 17 inventory in Nigeria mangrove forests 1.3 Objectives of the national forest 3 2.7.8 Estimation of biomass for 17 inventory in Nigeria standing and lying deadwood 1.4 Scope and limitations to the national 3 2.7.9 Estimation of biomass for 17 forest inventory undertaken stumps 2. Sampling methodology 5 2.7.10 Estimation of biomass for 18 litter 2.1 Sampling design and distribution 5 2.7.11 Estimation of carbon stocks in 18 2.2 Field sample plot layout 6 different ecological zones 3. Results 19 2.3 Field equipment for the Inventory 8 2.4 Team composition 10 3.1 Summary of field data 20 2.4.1 The Inventory team 10 3.2 Tree size distribution by ecological 20 zones 2.4.2 The sensitization team 10 3.3 Tree species diversity and relative 20 2.5 Field data collection from the 11 abundance carbon pools 3.4 Biomass and carbon stock estimates 27 2.5.1 Access to cluster location & 11 plot demarcation 3.4.1 Total (above and 27 belowground) live biomass 2.5.2 Measurement of standing live 11 trees, standing deadwood and 3.4.2 Standing and lying deadwood 27 stump measurements biomass 2.5.3 Downed deadwood 14 3.4.3 Total live and deadwood 28 measurement biomass and carbon stocks 2.5.4 Lower vegetation 14 4. Summary, conclusion, recommendations 31 and saplings 4.1 Summary and conclusion 31 2.5.5 Litter 14 4.2 Recommendations 31 2.5.6 Increment cores for wood 14 density determination References 32 2.6 Data verification and 14 Appendices 33 cleaning 2.7 Data analysis 15 A.1 Wood density data based on 33 increment cores collected during 2.7.1 Calculating the plot area 15 inventory and scaling factor A.2 Compiled wood density data for 34 2.7.2 Wood density determination 15 tree species in Nigeria (based on for live trees increment cores and literature) 2.7. 3 Wood density determination 16 A.3 Location of cluster points sampled 38 for standing and downed across various ecological zones deadwood III Figures Figure 2.1 5 Ecological zones of Nigeria Figure 2.2 7 Sketch diagram of a cluster arrangement and nested plot Figure 3.1 19 Spatial distribution of sample clusters visited and measured in different ecological zones Figure 3.2 21 Percentage frequency distribution for the enumerated trees Figure 3.3 22 Frequency distribution of species by ecological zones Figure 3.4 22 Frequency distribution of species found in the freshwater swamp in Nigeria Figure 3.5 23 Frequency distribution of the most abundant species in the lowland rainforest in Nigeria Figure 3.6 24 Frequency distribution of species found in the mangrove ecosystem in Nigeria Figure 3.7 24 Frequency distribution of species found in the derived savanna in Nigeria Figure 3.8 25 Frequency distribution of major species found in the Guinea savanna in Nigeria Figure 3.9 26 Frequency distribution of species found in the Sudan and Sahel savanna in Nigeria Figure 3.10 26 Frequency distribution of species found in the montane forest in Nigeria IV Tables Table 1.1 2 Distribution of high forest monitoring plots in the lowland rainforest in Nigeria Table 2.1 6 Distribution of the clusters based on ecological zones and states Table 2.2 7 Sample unit specifications Table 2.3 8 List of materials supplied to each inventory team Table 2.5 10 Brief description of roles of the inventory crew members Table 2.6 11 Variables measured/observed in the sample plots Table 2.7 12 Codes used during field enumeration Table 2.8 15 Area of each nest and the corresponding scaling factor Table 2.9 17 Density values for deadwood Table 3.1 19 Number of clusters enumerated in each ecological zone Table 3.2 21 Distribution of enumerated trees into dbh classes in the various ecological zones Table 3.3 27 Biomass estimates for live trees in the different ecological zones in Nigeria Table 3.4 28 Biomass estimates for standing deadwood and lying deadwood in Nigeria Table 3.5 28 Biomass estimates for litter in three ecological zones in Nigeria Table 3.6 28 Total live and dead biomass and carbon stocks for different ecological zones in Nigeria V Acronyms and abbreviations AFDB African Development Bank IPCC Intergovernmental Panel on Climate Change AGB aboveground biomass MRV measurement, reporting BA basal area and verification BGB belowground biomass NFI National Forest Inventory CO carbon dioxide 2 NFMS National Forest Monitoring System CRS Cross River State NMFP Nigerian Montane Forest Project DB diameter at base PSPS permanent sample plots DBH diameter at breast height REDD+ Reducing emissions from deforestation DM diameter at middle and forest degradation and the role of DST stump diameter conservation, sustainable management of forests and enhancement of forest DT diameter at top carbon stocks EEC European Economic Community SLMS Satellite Land Monitoring Systems FAO Food and Agriculture Organization of TSPS Temporary Sample Plots the United Nations UNDP United Nations Development Programme FCPF Forest Carbon Partnership Facility UNFCCC United Nations Framework Convention FDF Federal Department of Forestry on Climate Change FGN Federal Government of Nigeria FMENV Federal Ministry of Environment FORMECU Forestry Management, Evaluation and Coordinating Unit FRELS Forest Reference Emission Levels FRIN Forestry Research Institute of Nigeria FRL forest reference level FRS Forest Resources Study FUTA Federal University of Technology, Akure HFMPP High Forest Monitoring Plots Project HT total height VI ©FAO ©FAO/John Fonweban ©FAO/John Fonweban Executive summary The Forest Carbon Partnership Facility (FCPF) of the World Bank has been supporting the Federal Government of Nigeria (FGN) to develop its REDD+ readiness mechanism and part of the funds were allocated to undertake a “low intensity” forest carbon inventory in Nigeria within the Technical Assistance (TA) Agreement (UTF/NIR/066/NIR) which was signed between the Government and the Food and Agriculture organization of the United Nations (FAO). An inventory design was developed, including a field operations manual, and field training was carried out to build the capacity of technical forestry staff on field data collection, database development and data analysis.