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Status and path of intergenerational transmission of poverty in rural China:A human capital investment perspective

Journal of Integrative Agriculture 2021年第4期20卷 1080-1091页

作者： BAI Yun-li ZHANG Lin-xiu SUN Ming-xing XU Xiang-bo Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101P.R.China UN Environment Programme-International Ecosystem Management Partnership Beijing 100101P.R.China

This paper focused on the intergenerational transmission of poverty in rural China by estimating the intergenerational transmission of earnings and stated its mechanism from the perspective of human capital investment before children participated in the labor *** data used in this study were longitude data collected in 2000 households of 100 villages among 25 counties across five provinces in 2005,2008,2012,2016,and *** and quantitative methods were *** found a significant intergenerational transmission of earnings in rural China,especially for the pairs of father–children and parents–*** intergenerational earnings'elasticities were much less than those in urban areas,which indicated better social mobility in rural areas than that in urban *** children with parents who could earn much were more likely to be invested before they participated in the labor market,gain a high education and have more *** cases further showed that the mechanism of human capital investment in children breaking the intergenerational transmission of poverty and promoting social mobility.

关键词： poverty intergenerational transmission human capital rural China

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Total phosphorus concentrations in surface water of typical agro- and forest ecosystems in China, 2004-2010

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Frontiers of Environmental Science & Engineering 2014年第4期8卷 561-569页

作者： Juan XIE Xinyu ZHANG Zhiwei XU Guofu YUAN Xinzhai TANG Xiaomin SUN D.J. BALLANTINE Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Department of Environmental Science Xi'an Jiaotong-Liverpool University Suzhou 215123 China

The concentrations of total phosphorus （TP） from 83 surface water sampling sites in 29 of the Chinese ecosystem Research network （CERN） monitored ecosystems, representing typical agro- and forest ecosystems, were assessed using monitoring data collected between 2004 and 2010 from still and flowing surface water. Results showed that, TP concentrations were significantly higher in agro-ecosystems than those in forest ecosystems both for still and flowing surface water. For agro- ecosystems, TP concentrations in the southern area were significantly higher than those in the northern and north- western areas for both still and flowing surface water, however no distinct spatial pattern was observed for forest ecosystems. In general, the median values of TP within agro- and forest ecosystems did not exceed the Class V guideline for still （0.2mg.L-1） or flowing （0.4mg.L-1） surface water, however, surface water at some agro- ecosystem sampling sites was frequently polluted by TE Elevated concentrations were mainly found in still surface water at the Changshu, Fukang, Linze and Naiman monitored ecosystems, where exceedance （〉 0.2 mg.L-1） frequencies varied from 43% to 78%. For flowing water, elevated TP concentrations were found at the Hailun, Changshu and Shapotou monitored ecosystems, where exceedance （〉 0.4 mg. L-1） frequencies varied from 29% to 100%. Irrational fertilization, frequent irrigation and livestock manure input might be the main contributors of high TP concentrations in these areas, and reduced fertilizer applications, improvements in irrigation practices and centralized treatment of animal waste are necessary to control P loss in these TP vulnerable zones.

关键词： Chinese ecosystem Research network

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Effects of climate and forest age on the ecosystem carbon exchange of afforestation

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Journal of Forestry Research 2020年第2期31卷 365-374页

作者： Zhi Chen Guirui Yu Qiufeng Wang Synthesis Research Center of Chinese Ecosystem Research Network and Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101People’s Republic of China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049People’s Republic of China

Afforestation is believed to be an effective practice to reduce global warming by sequestering large amounts of carbon in plant biomass and ***,the factors that determine the rate of carbon sequestration with afforestation are still poorly *** analyzed ecosystem carbon exchange after afforestation based on eddy covariance measurements with the aim to identify factors responsible for the rate of carbon exchange following *** results indicated that afforestation in the tropical/subtropical and temperate climate zones had greater capacities for carbon sequestration than those in boreal *** ecosystem production(NEP),gross primary production(GPP)and ecosystem respiration(RE)varied greatly with age groups over ***,NEP was initially less than zero in the\10 year group and then increased to its peak in the 10-20 year *** of varied previous land use types and planting of diverse tree species did not result in different carbon *** general linear model showed that climate zone and age of afforestation were the dominant factors influencing carbon *** factors jointly controlled 51%,61%and 63%of the variation in NEP,GPP and RE,*** to the strong regulation of climate on GPP and RE,NEP showed greater sensitivity to the age of *** results increase our understanding of the variation in ecosystem carbon exchange of afforestation and suggest that afforestation in subtropical and temperate areas after 20 years would yield greater carbon sink benefits than would afforestation of boreal regions.

关键词： Afforestation Carbon sequestration Eddy covariance Climate Age

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Identification of sand and dust storm source areas in Iran

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Journal of Arid Land 2015年第5期7卷 567-578页

作者： CAO Hui LIU Jian WANG Guizhou YANG Guang LUO Lei Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences International Ecosystem Management Partnership United Nations Environment Programme University of Chinese Academy of Sciences Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences

Sand and dust storms （SDS） are common phenomena in arid and semi-arid areas. In recent years, SDS frequencies and intensities have increased significantly in Iran. A research on SDS sources is important for understanding the mechanisms of dust generation and assessing its socio-economic and environmental impacts. In this paper, we developed a new approach to identify SDS source areas in Iran using a combination of nine related datasets, namely drought events, temperature, precipitation, location of sandy soils, SDS frequency, hu- man-induced soil degradation （HISD）, human influence index （HII）, rain use efficiency （RUE） and net primary pro- ductivity （NPP） loss. To identify SDS source areas, we firstly normalized these datasets under uniform criteria in- cluding layer reprojection using Lambert conformal conic projection, data conversion from shapefile to raster, Min-Max Normalization with data range from 0 to 1, and data interpolation by Kriging and images resampling （resolution of 1 km）. After that, a score map for the possibility of SDS sources was generated through overlaying multiple datasets under average weight allocation criterion, in which each item obtained weight equally. In the score map, the higher the score, the more possible a specific area could be regarded as SDS source area. Exceptions mostly came from large cities, like Tehran and Isfahan. As a result, final SDS source areas were mapped out, and Al-Howizeh/Al-Azim marshes and Sistan Basin were identified as main SDS source areas in Iran. The SDS source area in Al-Howizeh/Al-Azim marshes still keeps expanding. In addition, Al-Howizeh/Al-Azim marshes are now suf- fering rapid land degradation due to natural and human-induced factors and might totally vanish in the near future. Sistan Basin also demonstrates the impacts of soil degradation and wind erosion. With appropriate intensity, dura- tion, wind speed and altitude of the dust storms, sand particles uplifting from this area might have developed

关键词： sand and dust storm weight allocation criterion Kriging interpolation score map AI-Howizeh/AI-Azim marshes Sistan Basin

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A Brief Introduction to Chinese ecosystem Research network(CERN)

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Journal of Resources and Ecology 2015年第3期6卷 192-196页

作者： LI Shenggong YU Guirui YU Xiubo HE Honglin GUO Xuebing Synthesis Center for Chinese Ecosystem Research Network CAS Key Laboratory of Ecosystem Network Observation and Modeling CAS Institute of Geographic Sciences and Natural Resources Research CAS

An ecosystem communities with is one or many a variety of biotic （living organisms including plants, animals and microbes） and abiotic （things like air, water and mineral soil） components that function in an interrelated fashion （Chapin et al. 2012）. These biotic and abiotic components linked together through nutrient cycles and energy flows （Chapin et al. 2012）. ecosystems provide humanity with a wide range of services, which are vital to sustaining human health and well-being, and social and economic development （MEA 2005）. These services are categorized into provisioning, regulating,

关键词：中国生态系统研究网络 CERN 经济社会发展人类健康非生物生态社区功能部件生物成分

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Field and Numerical Tests of the Two-Ponding Depth Procedure for Analysis of Single-Ring Pressure Infiltrometer Data

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Pedosphere 2013年第6期23卷 779-789页

作者： V.BAGARELLO M.IOVINO LAI Jian-Bin Dipartimento dei Sistemi Agro-Ambientali Universita degli Studi di PalermoViale delle Scienze Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences

The two-ponding depth （TPD） analysis procedure of single-ring infiltrometer data can yield invalid results, i.e., negative values of the field-saturated soil hydraulic conductivity or the matric flux potential, denoting failure of the two-level run. The objective of this study was to test the performance of the TPD procedure in analyzing the single-ring infiltrometer data of different types of soils. A field investigation carried out in western Sici]y, Italy, yielded higher failure rates （40%） in two clay loam soils than in a sandy loam soil （25%）. A similar result, i.e., fine-textured soils yielding higher failure rates than the coarse-textured one, was obtained using numerically simulated infiltration rates. Soil heterogeneity and reading errors were suggested to be factors determining invalid results in the field. With the numerical data, allowing a less generic definition of soil heterogeneity, invalid TPD results were occasionally obtained with the simultaneous occurrence of a high random variation （standard deviation ≥ 0.5） and a well developed structural correlation for saturated hydraulic conductivity （correlation length 〉 20 cm）. It was concluded that a larger number of replicated runs should be planned to characterize fine-textured soils, where the risk to obtain invalid results is relatively high. Large rings should be used since they appeared more appropriate than the small ones to capture and average soil heterogeneity. Numerical simulation appeared suitable for developing improved strategies of soil characterization for an area of interest, which should also take into account macropore effects.

关键词： field-saturated hydraulic conductivity infiltration rate numerical simulation soil heterogeneity soil texture

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Agricultural Land Suitability of Production Space in the Taihang Mountains, China

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Chinese Geographical Science 2019年第6期29卷 1024-1038页

作者： GENG Shoubao SHI Peili ZONG Ning ZHU Wanrui 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

The contradiction between the shortage of land for agriculture due to rapid expansion of industrialization and urbanization and increasing population pressure is projected to impose great threats to future food *** land suitability evaluation is an effective approach to improve the utilization of land resources for crop production and thus enhance the capacity of food *** this study, we evaluated the land suitability for agriculture of the production space in the Taihang Mountains by three steps: establishing indicator system, determining weights for indicators, and constructing a fuzzy matter-element model to assess the grades of *** showed that the land suitability had a significant linear correlation with potential crop yields, indicating our evaluation was effective to predict crop *** spatial pattern of land suitability for crop production demonstrated that land with higher suitability was generally located in piedmont plains and basins, while land with lower suitability was mostly situated in mountainous *** area of highly, moderately, marginally suitable and unsuitable land for agriculture was 32.13%, 28.58%, 37.49% and 1.80% of the production space, ***, the correlation degree analysis indicated that the requirements of these four suitability grades were currently not satisfied but could be potentially *** terms of indicator weights, soil properties were much more important than topography and location conditions to influence the grades of *** all indicators, slope, soil organic matter, soil texture and soil depth were the most influential factors, so slope farming prevention and organic fertilization were most likely to improve land suitability for *** the outputs of our land suitability evaluation model with the distribution of the existing croplands, we found that about 66.52% of marginally suitable and 54.55% of unsuitable land for agricul

关键词： agricultural land suitability matter-element model production space the Taihang Mountains

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Exploring the relationship between vegetation and dust-storm intensity(DSI) in China

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Journal of Geographical Sciences 2016年第4期26卷 387-396页

作者：谈明洪 Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchCAS

It is difficult to estimate the effects of vegetation on dust-storm intensity （DSI） since land surface data are often recorded aerially while DSI is recorded as point data by weather stations. Based on combining both types of data, this paper analyzed the relationship be- tween vegetation and DSI, using a panel data-analysis method that examined six years of data from 186 observation stations in China. The multiple regression results showed that the relationship between changes in vegetation and variance in DSI became weaker from the sub-humid temperate zone （SHTZ） to dry temperate zone （DTZ）, as the average normalized difference vegetation index decreased in the four zones in the study area. In the SHTZ and DTZ zones, the regression model could account for approximately 24.9% and 8.6% of the DSI variance, respectively. Lastly, this study provides some policy implications for combating dust storms.

关键词： relationship dust-storm intensity land surface feature northern China

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Wetland Restoration Is Effective but Insufficient to Compensate for Soil Organic Carbon Losses From Degradation

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Global Ecology and Biogeography 2025年第5期34卷

作者： Yanan Wu Ruiyang Zhang Andrew S. MacDougall Dashuan Tian Jinsong Wang Shuli Niu Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Department of Integrative Biology University of Guelph Guelph Ontario Canada Department of Environment and Resources University of Chinese Academy of Sciences Beijing China

Aim To assess the effectiveness of wetland restoration in reversing soil organic carbon (SOC) loss from degradation. Location Global. Time Period 1996–2023. Major Taxa Studied Wetland. Methods We conducted a global meta-analysis to compare SOC levels in restored, degraded, and natural wetlands across different restoration approaches and wetland types and to examine the dynamic trajectories of SOC recovery and the influence of climatic and edaphic factors. Results We found that passive restoration increased SOC in degraded sites by 141%, compared to an 8% increase from active restoration. Restored inland wetlands showed an increase in SOC of 118%, while coastal wetlands showed a limited improvement of 5%, in comparison with degraded wetlands. Increases in SOC primarily occurred within the first 10 years after restoration and then levelled off. That being said, SOC accumulation in restored wetlands rarely approached the levels found in natural wetlands, highlighting the importance of protecting wetlands from degradation for SOC targets. key factors for wetland SOC restoration were total soil nitrogen and mean annual temperature. Main Conclusions We conclude that wetland restoration is effective but insufficient to compensate for SOC losses from degradation. This study provides valuable insights for climate change mitigation through wetland restoration, supporting the goals of the United Nations Decade on ecosystem Restoration and the Paris Agreement.

关键词： carbon sequestration dynamic trajectory passive restoration soil organic carbon wetland restoration

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Response of soil CO_2 efflux to precipitation manipulation in a semiarid grassland

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Journal of Environmental Sciences 2016年第7期28卷 207-214页

作者： Xiaorong Wei Yanjiang Zhang Jian Liu Hailong Gao Jun Fan Xiaoxu Jia Jimin Cheng Mingan Shao Xingchang Zhang State Key Laboratory of Soil Erosion and Dryland Farming in the Loess Plateau Northwest A&F University College of Animal Science and Technology Northwest A&F University Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of Sciences

Soil CO_2efflux（SCE） is an important component of ecosystem CO_2 exchange and is largely temperature and moisture dependent, providing feedback between C cycling and the climate system. We used a precipitation manipulation experiment to examine the effects of precipitation treatment on SCE and its dependences on soil temperature and moisture in a semiarid grassland. Precipitation manipulation included ambient precipitation, decreased precipitation（- 43%）, or increased precipitation（＋ 17%）. The SCE was measured from July2013 to December 2014, and CO_2 emission during the experimental period was *** response curves of SCE to soil temperature and moisture were analyzed to determine whether the dependence of SCE on soil temperature or moisture varied with precipitation manipulation. The SCE significantly varied seasonally but was not affected by precipitation treatments regardless of season. Increasing precipitation resulted in an upward shift of SCE–temperature response curves and rightward shift of SCE–moisture response curves,while decreasing precipitation resulted in opposite shifts of such response curves. These shifts in the SCE response curves suggested that increasing precipitation strengthened the dependence of SCE on temperature or moisture, and decreasing precipitation weakened such dependences. Such shifts affected the predictions in soil CO_2 emissions for different precipitation treatments. When considering such shifts, decreasing or increasing precipitation resulted in 43 or 75% less change, respectively, in CO_2 emission compared with changes in emissions predicted without considering such shifts. Furthermore, the effects of shifts in SCE response curves on CO_2 emission prediction were greater during the growing than the non-growing season.

关键词： Soil CO2 efflux response curve Soil moisture Soil temperature Precipitation regimes Semiarid grassland Soil CO2 efflux

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