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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 Hunger.This 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 effect.This 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 2019.The 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 micronutrients.The 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 income.The 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 countries.These 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 areas.However,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

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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 Sciences College of Resources and Environment University of Chinese Academy of Sciences

Wetland ecosystems have become one of the long-term solutions for mitigating global climate change due to their strong carbon sequestration potential. However, the key carbon cycle processes in wetland ecosystems still lack a systematic summary. In 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 ecosystems. In 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 wetlands. Based 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 technology. The key technologies under each pathway are further refined. And the carbon sink effects of the carbon sink technologies in different wetland types are qualitatively described. Also, wetland protection and restoration methods in corresponding regions are given in the light of the regional characteristics of wetlands in China. This 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

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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 dynamics.However,assigning parameter values can be a technical challenge for structurally complex natural plant communities;uncertainties in model simulations often arise from inappropriate model parameterization.Here 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

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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 treatment.The 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)) emissions.The incorporation of February orchid and winter oilseed rape decreased nitrate leaching compared with the hairy vetch treatment in the maize growing season.The 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 are critical measures to promote winter cover c

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

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Ecological impacts of the expansion of offshore wind farms on trophic level species of marine food chain

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Journal of Environmental Sciences 2024年第5期139卷 226-244页

作者： Lijing Wang Bangguo Wang Wenxi Cen Rui Xu Yuwei Huang Xin Zhang Yinghui Han Yuanxun Zhang College of Resources and Environment University of Chinese Academy of SciencesBeijing 101408China Yanshan Earth Critical Zone and Surface Fluxes research Station University of Chinese Academy of SciencesBeijing 101408China chinese research Academy of Environmental Sciences Beijing 100012China National Joint research center for Yangtze River Conservation Beijing 100012China College of Environmental Engineering Beijing University of TechnologyBeijing 100124China Institute of Eco-Environmental Forensics Shandong UniversityQingdao 266237China

The global demand for renewable energy has resulted in a rapid expansion of offshore wind farms(OWFs)and increased attention to the ecological impacts of OWFs on the marine ecosystem.Previous reviews mainly focused on the OWFs’impacts on individual species like birds,bats,or mammals.This review collected numerous field-measured data and simulated results to summarize the ecological impacts on phytoplankton,zooplankton,zoobenthos,fishes,and mammals from each trophic level and also analyze their interactions in the marine food chain.Phytoplankton and zooplankton are positively or adversely affected by the‘wave effect’,‘shading effect’,oxygen depletion and predation pressure,leading to a ±10% fluctuation of primary production.Although zoobenthos are threatened transiently by habitat destruction with a reduction of around 60% in biomass in the construction stage,their abundance exhibited an over 90% increase,dominated by sessile species,due to the‘reef effect’in the operation stage.Marine fishes and mammals are to endure the interferences of noise and electromagnetic,but they are also aggregated around OWFs by the‘reef effect’and‘reserve effect’.Furthermore,the complexity of marine ecosystem would increase with a promotion of the total system biomass by 40% through trophic cascade effects strengthen and resource partitioning alternation triggered by the proliferation of filter-feeders.The suitable site selection,long-term monitoring,and life-cycle-assessment of ecological impacts of OWFs that are lacking in current literature have been described in this review,as well as the carbon emission and deposition.

关键词： Offshore wind farms(OWFs) Ecological impacts Plankton Benthos Fish Mammal

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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 hydrology.The impact of environmental changes on water quantity,and the evaluation and quantification of eco-hydrological processes remain poorly addressed.In 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 processes.The 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 seasons.Karst water line-conditioned excess(lc-excess)indicated that karst water interacted with recent precipitation,groundwater,and evaporation across seasons.Owing to its specific hydrogeological structure,surface water and rainwater have a higher contribution rate to groundwater replenishment.The 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 season.In 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

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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 ecosystems.Determining 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 lacking.In 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(R.pseudoacacia and P.sylvestris)and shrub(C.korshinkii and H.rhamnoides)species at 246 meteorological sites over NWD.The 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 species.Spatial 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 species.Spatial 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 R.pseudoacacia and H.rhamnoides.In 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 P.sylvestris,C.korshinkii and H.rhamnoides,respectively.In the desert sub-area(MAP:90 to 500 mm),the OVC ranged from 0.4 t

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

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Strategies on biosynthesis and production of bioactive compounds in medicinal plants

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chinese Herbal Medicines 2024年第1期16卷 13-26页

作者： Miaoxian Guo Haizhou Lv Hongyu Chen Shuting Dong Jianhong Zhang Wanjing Liu Liu He Yimian Ma Hua Yu Shilin Chen Hongmei Luo Key Lab of chinese Medicine Resources Conservation State Administration of Traditional Chinese Medicine of ChinaInstitute of Medicinal Plant DevelopmentChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100193China Engineering research center of chinese Medicine Resource Ministry of EducationBeijing 100193China Key Laboratory of Hangzhou City for ecosystem Protection and Restoration College of Life and Environmental SciencesHangzhou Normal UniversityHangzhou 311121China Chengdu University of Traditional chinese Medicine Chengdu 611137China

Medicinal plants are a valuable source of essential medicines and herbal products for healthcare and disease therapy.Compared with chemical synthesis and extraction,the biosynthesis of natural products is a very promising alternative for the successful conservation of medicinal plants,and its rapid development will greatly facilitate the conservation and sustainable utilization of medicinal plants.Here,we summarize the advances in strategies and methods concerning the biosynthesis and production of natural products of medicinal plants.The strategies and methods mainly include genetic engineering,plant cell culture engineering,metabolic engineering,and synthetic biology based on multiple“OMICS”technologies,with paradigms for the biosynthesis of terpenoids and alkaloids.We also highlight the biosynthetic approaches and discuss progress in the production of some valuable natural products,exemplifying compounds such as vindoline(alkaloid),artemisinin and paclitaxel(terpenoids),to illustrate the power of biotechnology in medicinal plants.

关键词： biosynthetic strategies biotechnology natural products medicinal plants synthetic biology

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Reply to “Beyond microbial carbon use efficiency”

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National Science Review 2024年第4期11卷 35-37页

作者： Feng Tao Johannes Lehmann Ying-Ping Wang Lifen Jiang Bernhard Ahrens Kostiantyn Viatkin Stefano Manzoni Benjamin Z.Houlton Yuanyuan Huang Xiaomeng Huang Yiqi Luo Department of Ecology and Evolutionary Biology Cornell University Soil and Crop Sciences Section School of Integrative Plant ScienceCornell University CSIRO Environment Max Planck Institute for Biogeochemistry Department of Physical Geography and Bolin Centre for Climate research Stockholm University Department of Global Development Cornell University Key Laboratory of ecosystem network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Department of Earth System Science Ministry of Education Key Laboratory for Earth System Modelling Institute for Global Change Studies Tsinghua University

In their commentary, Xiao et al.[1]cautioned that the conclusions on the critical role of microbial carbon use efficiency (CUE) in global soil organic carbon (SOC) storage in the paper by Tao et al.[2] might be too simplistic.They claimed that Tao et al.’s study lacked mechanistic consideration of SOC formation and excluded important data sets.Xiao et al. brought up important points,which can be largely reconciled with our findings by understanding the differences in expressing processes in empirical studies and in models.

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The storage and utilization of carbohydrates in response to elevation mediated by tree organs in subtropical evergreen broad-leaved forests

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Forest ecosystems 2024年第1期11卷 52-61页

作者： Bin Xu Xueli Jiang Yingying Zong G.Geoff Wang Fusheng Chen Zhenyu Zhao Xiangmin Fang Key Laboratory of National Forestry and Grassland Administration on Forest ecosystem Protection and Restoration of Poyang Lake Watershed College of ForestryJiangxi Agricultural UniversityNanchang330045China Jiulianshan National Observation and research Station of chinese Forest ecosystem College of ForestryJiangxi Agricultural UniversityNanchang330045China Department of Forestry and Environmental Conservation Clemson UniversityClemsonSC29634USA

Global climate change can affect tree growth and carbon sink function by influencing plant carbohydrate synthesis and utilization,while elevation can be used as an ideal setting under natural conditions to simulate climate change effects.The effect of elevation on tree growth may depend on organ type.However,the allocation patterns of nonstructural and structural carbohydrates(NSCs and SCs,respectively)in different tree organs and their response to elevation remain unclear.We selected four dominant tree species,Schima superba,Castanopsis eyrei,Castanopsis fargesii and Michelia maudiae,along an elevation gradient from 609 to 1,207 m in subtropical evergreen broad-leaved forests and analyzed leaf,trunk,and fine root NSCs,carbon(C),nitrogen(N)and phosphorus(P)concentrations and the relative abundance of SCs.Leaf NSCs increased initially and then decreased,and trunk NSCs increased with increasing elevation.However,root NSCs decreased with increasing elevation.The relative abundance of SCs in leaves and trunks decreased,while the relative abundance of root SCs increased with increasing elevation.No significant correlations between SCs and NSCs in leaves were detected,while there were negative correlations between SCs and NSCs in trunks,roots,and all organs.Hierarchical partitioning analysis indicated that plant C/N and C/P were the main predictors of changes in SCs and NSCs.Our results suggest that tree organs have divergent responses to elevation and that increasing elevation will inhibit the aboveground part growth and enhance the root growth of trees.A tradeoff between the C distribution used for growth and storage was confirmed along the elevation gradient,which is mainly manifested in the"sink"organs of NSCs.Our results provide insight into tree growth in the context of global climate change scenarios in subtropical forest ecosystems.

关键词： Nonstructural carbohydrates Structural carbohydrates Elevation Subtropical evergreen broad-leaved forests Tree organs

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