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Journal of Forestry Research 2024年第4期35卷 156-170页

作者： Shengwang Meng Qianyanzhou Ecological Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101People’s Republic of China

Quantifying the biomass of saplings in the regeneration component is critical for understanding biogeochemical processes of forest ***,accurate allometric equations have yet to be developed in sufficient *** develop species-specific and generalized allometric equations,154 saplings of eight Fagaceae tree species in subtropical China’s evergreen broadleaved forests were *** dendrometric variables,root collar diameter(d),height(h),and crown area(ca)were applied in the model by the weighted nonlinear seemingly unrelated regression *** only d as an input variable,the species-specific and generalized allometric equations estimated the aboveground biomass reasonably,with R _(adj)^(2) values generally>*** h and/or ca improved the fitting of some biomass components to a certain *** equations showed a relatively large coefficient of variation but comparable bias to species-specific *** in the absence of species-specific equations at a given location are generalized equations for mixed species *** developed regression equations can be used to accurately calculate the aboveground biomass of understory Fagaceae regeneration trees in China’s subtropical evergreen broadleaved forests.

关键词： Allometry Aboveground biomass Additivity Regeneration Subtropical China

key processes of carbon cycle and sink enhancement paths in natural wetland ecosystems in China

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Science China Earth Sciences 2024年第8期67卷 2444-2459页

作者： Jinshuai LI Tianxiang HAO Meng YANG Guirui YU key laboratory of ecosystem network observation and modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Wetland ecosystems have become one of the long-term solutions for mitigating global climate change due to their strong carbon sequestration ***,the key carbon cycle processes in wetland ecosystems still lack a systematic *** the context of wetland protection and restoration,there is still a lack of consensus on the technical pathways to realize carbon sink multiplication in wetland *** this paper,the key processes of carbon cycle,such as photosynthetic carbon uptake,microbial carbon decomposition and carbon deposition and burial,are sorted out and summarized in four major wetland types,namely,swamp and peat wetlands,river and riparian wetlands,lake and lakeshore wetlands,and estuarine and coastal *** on the key processes of carbon cycle,three technological pathways for carbon sink multiplication are proposed,including,vegetation carbon sequestration and sink enhancement technology,soil carbon emission reduction technology and carbon deposition and burial *** key technologies under each pathway are further *** the carbon sink effects of the carbon sink technologies in different wetland types are qualitatively ***,wetland protection and restoration methods in corresponding regions are given in the light of the regional characteristics of wetlands in *** will provide a scientific basis for the strategy of doubling the carbon sinks of China′s wetland ecosystems.

关键词： Wetlands Carbon cycle Carbon sinks Technology pathways Conservation and restoration

Off-farm employment,agriculture production activities,and household dietary diversity in environmentally and economically vulnerable areas of Asia

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Journal of Integrative Agriculture 2024年第2期23卷 359-373页

作者： Yunli Bai Xuanye Zeng Chao Fu Linxiu Zhang key laboratory of ecosystem network observation and modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China United Nations Environment Programme-International ecosystem Management Partnership(UNEP-IEMP) Beijing 100101China University of Chinese Academy of Sciences Beijing 100101China

Access to off-farm employment has been expected to be a critical approach to ending hunger and all forms of malnutrition,two important targets of achieving Zero *** study aims to investigate the role of off-farm employment in improving dietary diversity through substitution effect and complementary effect with agricultural production activities and income *** study adopts Poisson/Tobit/Probit/OLS regressions and the instrument variable method based on the primary survey data collected among 1,282 households at 12 sites in environmentally and economically vulnerable areas of China,Nepal,Cambodia,Thailand,and Myanmar in *** results show that off-farm employment is positively associated with household dietary diversity and the consumption of flesh meat,fish and other aquatic animals,fruits,and milk and dairy products,which are rich in protein and *** results of mechanism analysis show that off-farm employment contributes to household dietary diversity by improving crop diversity,especially for poor households,boosting the probability of livestock raising for households with the middle one-third disposal income,and increasing household *** positive association between off-farm employment and household dietary diversity is much higher for households with the bottom one-third disposal income,low illiteracy,and from upper-middle income *** findings imply that off-farm employment does play a vital role in achieving multiple benefits of poverty alleviation,malnutrition reduction,and agrobiodiversity conservation in environmentally and economically vulnerable ***,it may enlarge the gaps in dietary diversity between households with low human capital and from low and lower-middle income countries and those with high human capital and from middle-high countries.

关键词： off-farm employment dietary diversity income effect substitution effect complementary effect

The Impacts of Climate Change and Human Activities on Cropland Net Primary Productivity in Bangladesh,India and Myanmar

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Journal of Resources and Ecology 2024年第4期15卷 814-825页

作者： WANG Chunyu WANG Junbang School of Geography and Tourism Qilu Normal UniversityJinan 250200China National ecosystem Science Data Center Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Under global change and climate variations,determining the impacts of climate change and human activities on cropland net primary productivity(NPP)in Bangladesh,India and Myanmar(BIM)is of great significance for identifying yield-limiting factors,making adaptive agricultural management plans,and improving *** on the GLOPEM-CEVSA model,through an integration of remote sensing data and LAI simulation,we investigated the impacts and spatiotemporal changes of water and human activities on BIM from 1982 to *** types of cropland NPPs were considered:actual NPP(NPPA),NPP affected by temperature and water(NPPWT),and NPP only affected by temperature(NPPT).Our analysis revealed that the water factor plays a predominant role in determining the NPP level in the *** variability was found to be conducive to NPPT,exhibiting an increasing trend of 10.66 g C m^(-2) yr^(-1).However,this trend was partially offset by precipitation variability,resulting in a net increase of 0.96 g C m^(-2) yr^(-1).In comparing temperature-driven NPP to temperature and water-driven NPP,water stress caused NPPT to decrease by 65.46% compared to NPPWT for the entire *** NPP in northwestern India and the central Deccan Plateau were significantly affected by water ***,the influence of water on NPP in the BIM exhibited a substantial upward trend from 1982 to 2015,with Myanmar experiencing the most significant *** gap between NPPWT and NPPA in BIM demonstrated a notable decreasing trend during the same period,underscoring the positive impact of human activities on *** drawn from our findings suggest that with the implementation of rational and efficient crop management practices,there is a 36.80% potential improvement in NPPA compared to NPPWT in the BIM region,with India and Myanmar showing potential increases of 39.20% and 38.29%,*** insights provide guidance for practical measures aimed at water resource management to en

关键词： NPP climate change human activities water stress GLOPEM-CEVSA model Bangladesh India Myanmar

Isotopic insights on quantitative assessments of interaction of eco-hydrological processes in multi-scale karst watersheds

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International Soil and Water Conservation Research 2024年第1期12卷 156-170页

作者： Zhuo Hao Yang Gao Qingwen Zhang Wen Wen Agricultural Clean Watershed Research Group Institute of Environment and Sustainable Development in AgricultureCAASBeijing100081China key laboratory of ecosystem network observation and modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing100101China School of Humanities and Social Sciences Beijing Institute of TechnologyBeijing100081China

The dynamics of hydrological processes and the storage mechanisms of karst water resources are the most important issues in karst *** impact of environmental changes on water quantity,and the evaluation and quantification of eco-hydrological processes remain poorly *** this study,high-frequency continuous monitoring in multi-scale karst watersheds in Southwest China combined the approaches of water isotopes and the hybrid single-particle lagrangian integrated trajectory(HYSPLIT)model to identify the recharge mechanisms between atmospheric vapor,rainfall,surface water,and groundwater,and to reveal the interaction of eco-hydrological *** dominant moisture sources in Puding(PD)County were the Indian Ocean(43-69%)and local moisture(24-33%).Theδ^(18)O and deuterium excess(d-excess)values showed a positive correlation indicating that secondary or sub-cloud evaporation was prominent in the wet *** water line-conditioned excess(lc-excess)indicated that karst water interacted with recent precipitation,groundwater,and evaporation across *** to its specific hydrogeological structure,surface water and rainwater have a higher contribution rate to groundwater *** Chenqi stream replenished the Houzhai River mainly in the form of groundwater,with percentages ranging from 38.1 to 93.5%in the wet season,and 47.8-80.1%in the dry *** the Houzhai outlet,surface water and groundwater interconverted frequently with a percentage of 45.6-49.1%.We believe this is the first systematic study to quantify the supply relationship between water vapor transport,rainfall,surface water and groundwater in the Chinese karst zone,making a significant move forward in the field of karst hydrological processes and improving the efficiency of water resource evaluation and management.

关键词： Stable isotope Moisture sources Water cycle Karst watersheds

Environmental benefits and farmers' adoption of winter cover crops in the North China Plain

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Pedosphere 2024年第1期34卷 159-169页

作者： Shufang GUO Yitao ZHANG Limei ZHAI Jian LIU Hongyuan WANG Hongbin LIU State key laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China Key Laboratory of Nonpoint Source Pollution ControlMinistry of Agriculture and Rural AffairsInstitute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081China Institute of Agricultural Environment and Resources Yunnan Academy of Agricultural SciencesKunming 650205China Shandong Yucheng Agro-ecosystem National observation Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China The Norwegian Institute of Bioeconomy Research(NIBIO) Akershus 1431Norway

The introduction of cover crops into monoculture systems to improve soil health has been widely adopted worldwide. However, little is known about the environmental risks and application prospects of different cover crops in spring maize(Zea mays L.) monocultures proposed in the North China Plain. A pot experiment was conducted to evaluate the effects of different winter cover crops on subsequent maize yield, soil fertility, and environmental risks of nitrogen(N) loss, and a questionnaire survey was conducted to examine factors influencing farmers' willingness to adopt cover crops in the North China Plain. Based on the same fertilization regime during the maize growing period, four winter cover crop treatments were set up, including bare fallow, hairy vetch(Vicia villosa Roth.), February orchid(Orychophragmus violaceus), and winter oilseed rape(Brassica campestris L.). The results indicated that winter cover crops significantly increased subsequent maize yield and soil organic carbon, total N, and microbial biomass carbon and N compared with the bare fallow *** incorporation of cover crops led to a negligible increase in nitrous oxide(N_(2)O) emissions and had a very limited effect on ammonia(NH_(3)) *** incorporation of February orchid and winter oilseed rape decreased nitrate leaching compared with the hairy vetch treatment in the maize growing *** N losses via N_(2)O and NH_(3) emissions and N leaching accounted for 71%–84% of the N surplus. However, yield increase and environmental benefits were not the main positive factors for farmers to accept cover crops. Financial incentive was rated by 83.9% of farmers as an “extremely important” factor, followed by other costs, when considering winter cover cropping. These results indicate that the environmental benefits depend on the type of cover crop. Maintaining high levels of soil fertility and maize yield, providing sufficient subsidies, and encouraging large-area cultivation of cover crops

关键词： cover crop N leaching NH_(3)emission N_(2)O emission spring maize willingness to accept

Cultivated Grassland Development on the Tibetan Plateau:Current Status,Challenges,Suggestions

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Journal of Resources and Ecology 2024年第4期15卷 804-813页

作者： HOU Ge SHI Peili ZHAO Guangshuai CHEN Xueying HUANG Xiaofang DUAN Cheng key laboratory of ecosystem network observation and modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Development Research Center National Forestry and Grassland AdministrationBeijing 100714China University of Chinese Academy of sciences Beijing 100049China

The Tibetan Plateau is vital for animal husbandry in China,and relies heavily on its natural ***,grassland degradation,increasing livestock numbers,and uneven grazing practices are exacerbating the grass-livestock *** grasslands are a key strategy to address this *** this review,we evaluate the current status,challenges,and suggestions for developing and managing Tibetan Plateau cultivated *** discernible advancements have been made in the cultivated grasslands in this region,persistent challenges *** challenges stem from issues like low awareness and enthusiasm among farmers and herders,uneven cultivated grassland distribution,and limited scientific and technological *** on these challenges,we propose strengthening the promotion of artificial forage,implementing a rationalized grassland layout,and improving the scientific and technological contributions to forage species selection,sowing,management,and *** summary,cultivated grasslands in the Tibetan Plateau offer promising prospects but still face significant *** these obstacles will require innovative approaches to unlock the full potential of cultivated grasslands in this unique ecological niche.

关键词： animal husbandry balance of grass and livestock cultivated grassland Tibetan Plateau

In-situ warming does not change soil priming effect induced by glucose addition in a temperate forest

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Pedosphere 2024年第4期34卷 759-769页

作者： Xiaohan DONG Yunting FANG Dongwei LIU Xin GUAN Kai HUANG Yuqi LIU Qingkui WANG Silong WANG Weidong ZHANG Huitong Experimental Station of Forest Ecology CAS Key Laboratory of Forest Ecology and ManagementInstitute of Applied EcologyShenyang 110016China University of Chinese Academy of Sciences Beijing 101408China Hunan key laboratory for Structure and ecosystem Service of Subtropical Forest Huitong National Research Station of Forest EcosystemHuitong 418307China Qingyuan Forest Chinese ecosystem Research network(CERN) National Observation and Research StationShenyang 110016China key laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016(China)f Key Laboratory of Stable Isotope Techniques and ApplicationsShenyang 110016China key laboratory of Terrestrial ecosystem Carbon Neutrality Shenyang 110016China

Priming effect(PE)on soil organic carbon(SOC)decomposition caused by the addition of organic carbon(C)is an important ecological process in regulating soil C ***,most priming studies are confined to laboratory trials,while the assessment of soil PE under field conditions with variable weather conditions is *** study assessed the direct effects of glucose addition and in-situ warming on the extent of PE under field conditions in a temperate *** evaluated soil PE using 13C-glucose labelling,a simple and novel technique,based on the Keeling plot *** addition significantly enhanced native SOC decomposition and induced strong ***,the effect of in-situ warming on the extent of PE was not *** study confirms the importance of PE in regulating SOC turnover under field conditions.

关键词： lue lblling tchnquegbal wamingrmingt hppidfaty ai solganmattermineralisatn oezme respiration

Estimating the optimal vegetation coverage for the dominant tree and shrub species over China's northwest drylands

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Science China Earth Sciences 2024年第5期67卷 1500-1517页

作者： Zhongdian ZHANG Xiaoxu JIA Ping ZHU Mingbin HUANG Lidong REN Ming’an SHAO School of Geographic Sciences Xinyang Normal UniversityXinyang 464000China key laboratory of ecosystem network observation and modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China Yellow River Delta Modern Agricultural Engineering laboratory Chinese Academy of SciencesBeijing 100101China State key laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China

Anthropogenic revegetation is an effective way to control soil erosion and restore degraded ecosystems in China's northwest drylands(NWD).However,excessive vegetation cover expansion has long been known to increase evapotranspiration,leading to reduced local water availability,which can in turn threaten the health and services of restored *** the optimal vegetation coverage(OVC)is critical for balancing the trade-off between plant growth and water consumption in water-stressed areas,yet quantitative assessments over the entire NWD are still *** this study,a modified Biome BioGeochemical Cycles(Biome-BGC)model was used to simulate the long-term(1961–2020)dynamics of actual evapotranspiration(ET_(a)),net primary productivity(NPP),and leaf area index(LAI)for the dominant non-native tree(*** and ***)and shrub(*** and ***)species at 246 meteorological sites over *** modified model incorporated the Richards equation to simulate transient unsaturated water flow in a multilayer soil module,and both soil and eco-physiological parameters required by the model were validated using field-observed ETadata for each *** distributions of OVC(given by the mean maximum LAI,LAI_(max))for the dominant species were determined within three hydrogeomorphic sub-areas(i.e.,the loess hilly-gully sub-area,the windy and sandy sub-area,and the desert sub-area).The modified Biome-BGC model performed well in terms of simulating ET_(a) dynamics for the four plant *** distributions of mean ET_a,NPP,and LAI_(max)generally exhibited patterns similar to mean annual precipitation(MAP).In the loess hilly-gully sub-area(MAP:210 to 710 mm),the OVC respectively ranged from 1.7 to 2.9 and 0.8 to 2.9 for *** and *** the windy and sandy sub-area(MAP:135 to 500 mm),the OVC ranged from 0.3 to 3.3,0.5 to 2.6 and 0.6 to 2.1for ***,*** and ***,*** the desert sub-

关键词： Optimal vegetation coverage Water balance Leaf area index Biome-BGC model Dryland

Implication of community-level ecophysiological parameterization to modelling ecosystem productivity:a case study across nine contrasting forest sites in eastern China

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Journal of Forestry Research 2024年第1期35卷 1-11页

作者： Minzhe Fang Changjin Cheng Nianpeng He Guoxin Si Osbert Jianxin Sun School of Ecology and Nature Conservation Beijing Forestry UniversityBeijing 100083China Research Institute of Energy Saving Environmental ProtectionOccupational Safety and HealthChina Academy of Railway Sciences Corporation LimitedBeijing 100081China key laboratory of ecosystem network observation and modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Parameterization is a critical step in modelling ecosystem ***,assigning parameter values can be a technical challenge for structurally complex natural plant communities;uncertainties in model simulations often arise from inappropriate model *** we compared five methods for defining community-level specific leaf area(SLA)and leaf C:N across nine contrasting forest sites along the North-South Transect of Eastern China,including biomass-weighted average for the entire plant community(AP_BW)and four simplified selective sampling(biomass-weighted average over five dominant tree species[5DT_BW],basal area weighted average over five dominant tree species[5DT_AW],biomass-weighted average over all tree species[AT_BW]and basal area weighted average over all tree species[AT_AW]).We found that the default values for SLA and leaf C:N embedded in the Biome-BGC v4.2 were higher than the five computational methods produced across the nine sites,with deviations ranging from 28.0 to 73.3%.In addition,there were only slight deviations(ecosystem process modelling,and will support the choice of parameterization methods.

关键词： Biome-BGC Community traits Forest ecosystems Model parameterization