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Developing individual tree-based models for estimating aboveground biomass of five key coniferous species in China

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Journal of forestry Research 2018年第5期29卷 1251-1261页

作者： Weisheng Zeng Liyong Fu Ming Xu Xuejun Wang Zhenxiong Chen Shunbin Yao academy of forest inventory and planning State Forestry Administration Research Institute of forest Resource Information Techniques Chinese Academy of Forestry Department of Ecology Evolution & Natural ResourcesRutgers University Central South forest inventory and planning Institute State Forestry Administration East China forest inventory and planning Institute State Forestry Administration

Estimating individual tree biomass is critical to forest carbon accounting and ecosystem service *** this study,we developed one-（tree diameter only） and two-variable（tree diameter and height） biomass equations,biomass conversion factor（BCF） models,and an integrated simultaneous equation system（ISES） to estimate the aboveground biomass for five conifer species in China,i.e.,Cunninghamia lanceolata（Lamb.） Hook.,Pinus massoniana Lamb.,*** Faranch,*** *** *** Engelm.,based on the field measurement data of aboveground biomass and stem volumes from 105. destructive sample trees across the *** found that all three methods,including the one-and two-variable equations,could adequately estimate aboveground biomass with a mean prediction error less than 5.,except for Pinus yunnanensis which yielded an error of about 6%.The BCF method was slightly poorer than the biomass equation and the ISES *** average coefficients of determination（R^2） were 0.944,0.938 and 0.943 and the mean prediction errors were 4.26,4.49 and 4.29% for the biomass equation method,the BCF method and the ISES method,*** ISES method was the best approach for estimating aboveground biomass,which not only had high accuracy but also could estimate stocking volumes simultaneously that was compatible with aboveground *** addition,we found that it is possible to develop a species-invariant one-variable allometric model for estimating aboveground biomass of all the five coniferous *** model had an exponent parameter of 7/3 and the intercept parameter a_0 could be estimated indirectly from stem basic density（a_0= 0.294 q）.

关键词： Biomass models Allometric equations Biomass conversion factor Error-in-variable simultaneous equations

Development of monitoring and assessment of forest biomass and carbon storage in China

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forest Ecosystems 2015年第1期2卷 1-10页

作者： Wei-Sheng Zeng academy of forest inventory and planning State Forestry Administration

Addressing climate change has become a common issue around the world in the 21st century and equally an important mission in Chinese *** the development of monitoring and assessment of forest biomass and carbon storage in China is important for promoting the evaluation of forest carbon sequestration capacity of *** author conducts a systematic analysis of domestic publications addressing＂monitoring and assessment of forest biomass and carbon storage＂in order to understand the development trends,describes the brief history through three stages,and gives the situation of new *** the end of the 20th century,a large number of papers on biomass and productivity of the major forest types in China had been published,covering the exploration and efforts of more than 20 years,while investigations into assessment of forest carbon storage had barely *** on the data of the 7th and 8th National forest Inventories,forest biomass and carbon storage of the entire country were assessed using individual tree biomass models and carbon conversion factors of major tree species,both previously published and newly *** the implementation of the 8th National forest inventory,a program of individual tree biomass modeling for major tree species in China was carried out *** means of thematic research on classification of modeling populations,as well as procedures for collecting samples and methodology for biomass modeling,two technical regulations on sample collection and model construction were published as ministerial standards for *** for approval of individual tree biomass models and carbon accounting parameters of major tree species have been issued for approval as ministerial *** the improvement of biomass models and carbon accounting parameters,thematic assessment of forest biomass and carbon storage will be gradually changed into a general monitoring of forest biomass and carbo

关键词： Biomass models Carbon accounting parameters Biomass conversion factor Root-to-shoot ratio Carbon storage

Applied research of landscape ecology in desertification monitoring and assessment

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Journal of Environmental Sciences 2000年第3期12卷 349-354页

作者： LI Feng, SUN Si heng (academy of forest inventory and planning/China National Desertification Monitoring Center, State forestry Administration, Beijing 100714, China) academy of forest inventory and planning/China National Dese 北京 1 0 0 71 4

A preliminary research on landscape ecology in desertification monitoring and assessment was reported. Also, this paper laid stress on the study of landscape diversity, dominance, evenness and Markov Matrix model and their respective landscape ecological meanings in the desertification monitoring and assessment. Concurrently, it took Shazhuyu Experimental Area, Qinghai Province as a specific case study.

关键词： landscape ecology desertification monitoring and assessment Shazhuyu Experimental Area

ON YIELD TABLE AND ITS GENERAL RESEARCH CONDITION IN CHINA

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Journal of Northeast forestry University 1992年第2期3卷 70-77页

作者： WengGuoqing Chang Kun forest inventory and planning academy Hao Wenkang Zhang Yanli Northeast forestry University Lcc Longchang Zhejiang forestry Institutc forest inventory and planning academy China Northeast forestry University China Zhejiang forestry Institute China

The development and rc research condition about yield table in China were in-troduced in this *** methods of constructing yield table were also described and studied in brief.

关键词： Yield table

Mapping the potential distribution suitability of 16 tree species under climate change in northeastern China using Maxent modelling

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Journal of forestry Research 2022年第6期33卷 1739-1750页

作者： Dan Liu Xiangdong Lei Wenqiang Gao Hong Guo Yangsheng Xie Liyong Fu Yuancai Lei Yutang Li Zhuoli Zhang Shouzheng Tang Key Laboratory of forest Management and Growth Modelling National Forestry and Grassland AdministrationInstitute of Forest Resource Information TechniquesChinese Academy of ForestryBeijing 100091People’s Republic of China academy of forest inventory and planning of Jilin Province Changchun 130022People’s Republic of China

Knowledge on the potential suitability of tree species to the site is very important for forest management *** forest distribution provides a good reference for afforestation and forest *** this study,we developed species distribution model(SDM)for 16 major tree species with 2,825.permanent sample plots with natural origin from Chinese National forest {5. data collected in Jilin Province using the Maxent *** types of environmental factors including bioclimate,soil and topography with a total of 33 variables were tested as the *** values of area under the curve(AUC,one of the receiver operating characteristics of the Maxent model)in the training and test datasets were between 0.784 and 0.968,indicating that the prediction results were quite *** environmental factors affecting the distribution of species were ranked in terms of their importance to the species ***,the climatic factors had the greatest contribution,which included mean diurnal range,annual mean temperature,temperature annual range,and *** the main environmental factors varied with tree *** suitability maps under current(195.-2000)and future climate scenarios(CCSM4-RCP 2.6 and RCP 6.0 during 205.)were produced for 16 major tree species in Jilin Province using the model *** predicted current and future ranges of habitat suitability of the 16 tree species are likely to be positively and negatively affected by future *** tree species were found to benefit from future climate including B etula costata,Fraxinus mandshurica,Juglans mandshurica,Phellodendron amurense,Populus ussuriensis,Quercus mongolica and Ulmus pumila;five tree species will experience decline in their suitable habitat including ***,Tilia mongolica,Picea asperata,Pinus sylvestris,Pinus koraiensis;and four(Salix koreensis,Abies fabri,Pinus densiflora and Larix olgensis)showed the inconsistency under RCP 2.6 and RC

关键词： Species distribution model National forest inventory data Natural forest Climate change Site suitability mapping Maxent modelling

Soil phosphorus fractions and their availability over natural succession from clear-cut of a mixed broadleaved and Korean pine forest in northeast China

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Journal of forestry Research 2022年第1期33卷 253-260页

作者： Peng Yu Xin Zhang Huiyan Gu Jianping Pan Xiangwei Chen Northeast forestry University Harbin 150040People’s Republic of China academy of forest and Grassland inventory and planning National Forestry and Grassland AdministrationBeijing 100714People’s Republic of China

To assess phosphorus(P)status of forest soil under naturally restored vegetation,P fractions in the 10-cm soil layer were quantified at different successional stages on the clear-cut site of mixed broadleaved and Korean pine *** communities of shrub,softwood broad-leaved forest,softwood and hardwood broad-leaved forest,and hardwood broad-leaved forest represented different successional stages.A soil sample from a primary broad-leaved and Korean pine stand was the control.A sequential P fractionation scheme extracted empirically defined pools of P and path analysis used to partition the direct and indirect contribution of soil P fractions to available *** results show that available P increased significantly with long-term succession,while both sodium bicarbonate-extractable P(NaHCO_(3)-P)and sodium hydroxide-extractable P(NaOHP)fractions were reduced in early successional stages and increased in late *** to the primary forest,concentrations of P fractions in the four stages significantly decreased except for HCl-P,indicating that soil P supplements over the long-term did not return to primary forest *** results of related analysis also showed that NaHCO_(3)-P_(i)levels were significantly related to available *** to the path analysis coefficient,NaHCO_(3)-P_(i)exhibited the highest effect on available P among eight P fractions;the indirect effects of other P fractions via NaHCO_(3)-P_(i)were larger than those with other P ***,this study suggests that soil P bioavailability gradually improved during natural vegetation restoration on clear-cut sites mainly through the increase of NaHCO_(3)-P,where phosphorous is immediately available,and subsequently available phosphorus Na OH-P.

关键词： Vegetation succession Available phosphorus Phosphorus fractions Correlation analysis Path analysis

The national forest inventory in China:history-results-international context

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forest Ecosystems 2015年第4期2卷 288-303页

作者： Wei Sheng Zeng Erkki Tomppo Sean P.Healey Klaus V.Gadow academy of forest inventory and planning State Forestry Administration Natural Resources Institute Finland forest Service United States Department of Agriculture University of G?ttingen Beijing forestry University Department of forestry and Wood Technology University of Stellenbosch

Background： National forest resource assessments Inventories （NFI＇s）, constitute an important nationa and monitoring, commonly known as National forest information infrastructure in many countries. Methods： This study presents details about developments of the NFI in China, including sampling and plot design and the uses of alternative data sources, and specifically · reviews the evolution of the national forest inventory in China through the 20th and 21st centuries, with some reference to Europe and the US; · highlights the emergence of some common international themes： consistency of measurement; sampling designs; implementation of improved technology; expansion of the variables monitored more efficient scientific transparency;· presents an example of how China＇s expanding NFI exemplifies these global trends. Results： Main results and important changes in China＇s NFI are documented, both to support continued trend analysis and to provide data users with historical perspective. Conclusions： New technologies and data needs ensure that the Chinese NFI, like the national inventories in other countries, will continue to evolve. Within the context of historical change and current conditions, likely directions for this evolution are suggested.

关键词： China Europe USA National forest inventories forest inventory and analysis

A density-dependent matrix model and its applications in optimizing harvest schemes

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Science China(Technological Sciences) 2006年第Z1期49卷 108-117页

作者： Guofan Shao, WANG Fei, DAI Limin, BAI Jianwei & LI Yingshan Department of forestry and Natural Resources, Purdue University, West Lafayette, IN 47907, USA Institute of Applied Ecology, Chinese academy of Sciences, Shenyang 110016, China Inner Mongolia Agriculture University, Hohhot 010019, China academy of forest inventory and {5., State forestry Administration, Beijing 100714, China Department of forestry and Natural Resources Purdue University West Lafayette USA Institute of Applied Ecology Chinese Academy of Sciences Shenyang China Inner Mongolia Agriculture University Hohhot China academy of forest inventory and planning State Forestry Administration Beijing China

Based on temporal data collected from 36 re-measured plots, transition probabilities of trees from a diameter class to a higher class were analyzed for the broad-leaved-Korean pine forest in the Changbai Mountains. It was found that the transition probabilities were related not only to diameter size but also to the total basal area of trees with the diameter class. This paper demonstrates the development of a density-dependent matrix model, DM2, and a series of simulations with it for forest stands with different conditions under different harvest schemes. After validations with independent field data, this model proved a suitable tool for optimization analysis of harvest schemes on computers. The optimum harvest scheme(s) can be determined by referring to stand growth, total timbers harvested, and size diversity changes over time. Three user-friendly interfaces were built with a forest management decision support system forestAR?for easy operations of DM2 by forest managers. This paper also summarizes the advantages and disadvantages of DM2.

关键词： uneven-aged forestry, diameter transition model, harvesting intensity, diameter limit, sustainable forest management.

Mapping forest age using National forest inventory,airborne laser scanning,and Sentinel-2 data

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forest Ecosystems 2020年第4期7卷 793-806页

作者： Johannes Schumacher Marius Hauglin Rasmus Astrup Johannes Breidenbach National forest inventory Norwegian Institute of Bioeconomy ResearchÅsNorway

Background:The age of forest stands is critical information for forest management and conservation,for example for growth modelling,timing of management activities and harvesting,or decisions about protection ***,area-wide information about forest stand age often does not *** this study,we developed regression models for large-scale area-wide prediction of age in Norwegian *** model development we used more than 4800 plots of the Norwegian National forest inventory(NFI)distributed over Norway between latitudes 5.°and 65.N in an 18.2 Mha study *** variables were based on airborne laser scanning(ALS),Sentinel-2,and existing public map *** performed model validation on an independent data set consisting of 63 spruce stands with known ***:The best modelling strategy was to fit independent linear regression models to each observed site index(SI)level and using a SI prediction map in the application of the *** most important predictor variable was an upper percentile of the ALS heights,and root mean squared errors(RMSEs)ranged between 3 and 31 years(6%to 26%)for SI-specific models,and 21 years(25.)on *** deviance(MD)ranged between^(−1) and 3 *** models improved with increasing SI and the RMSEs were largest for low SI stands older than 100 *** a mapped SI,which is required for practical applications,RMSE and MD on plot level ranged from 19 to 5. years(29%to 5.%),and 5.to 37 years(5.to 31%),*** the validation stands,the RMSE and MD were 12(22%)and 2 years(3%),***:Tree height estimated from airborne laser scanning and predicted site index were the most important variables in the models describing ***,we obtained good results,especially for stands with high *** models could be considered for practical applications,although we see considerable potential for improvements if better SI maps were available.

关键词： forest age Lidar Optical satellite images Remote sensing forest inventory