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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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Spatial pattern of grassland aboveground biomass and its environmental controls in the Eurasian steppe

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Journal of Geographical Sciences 2017年第1期27卷 3-22页

作者： JIAO Cuicui YU Guirui HE Nianpeng MA Anna GE Jianping HU Zhongmin Synthesis Research Center of Chinese Ecosystem Research Network Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China College of Life Sciences Beijing Normal UniversityBeijing 100875China

Vegetation biomass is an important component of terrestrial ecosystem carbon stocks. Grasslands are one of the most widespread biomes worldwideplaying an important role in global carbon cycling. Thereforestudying spatial patterns of biomass and their correlations to environment in grasslands is fundamental to quantifying terrestrial carbon budgets. The Eurasian steppean important part of global grasslandsis the largest and relatively well preserved grassland in the world. In this studywe analyzed the spatial pattern of aboveground biomass（AGB）and correlations of AGB to its environment in the Eurasian steppe by meta-analysis. AGB data used in this study were derived from the harvesting method and were obtained from three data sources（literatureglobal NPP database at the Oak Ridge National laboratory Distributed Active Archive Center（ORNL）some data provided by other researchers）. Our results demonstrated that：（1） as for the Eurasian steppe overallthe spatial variation in AGB exhibited significant horizontal and vertical zonality. In detailAGB showed an inverted parabola curve with the latitude and with the elevationwhile a parabola curve with the longitude. In additionthe spatial pattern of AGB had marked horizontal zonality in the Black Sea-Kazakhstan steppe subregion and the Mongolian Plateau steppe subregionwhile horizontal and vertical zonality in the Tibetan Plateau alpine steppe subregion.（2） Of the examined environmental variablesthe spatial variation of AGB was related to mean annual precipitation（MAP）mean annual temperature（MAT）mean annual solar radiation（MAR）soil Gravel contentsoil p H and soil organic content（SOC） at the depth of 0–30 cm. NeverthelessMAP dominated spatial patterns of AGB in the Eurasian steppe and its three subregions.（3） A Gaussian function was found between AGB and MAP in the Eurasian steppe overallwhich was primarily determined by unique patterns of grasslands and environment in the Tibetan Plateau. AGB was significantly positively relat

关键词： the Eurasian steppe aboveground biomass spatial pattern parabola curve Gaussian function

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

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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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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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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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Partial organic substitution for chemical fertilizer reduces N₂O emissions but increases the risk of N loss through nitrification in Tibetan farmland

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Scientific Reports 2025年第1期15卷 1-14页

作者： Huang, Xiaofang Yu, Chengqun Sun, Wei Shi, Peili Wu, Junxi Yu, Jialuo Wang, Jiabao Mu, Tao Key Laboratory of Ecosystem Network Observation and Modelling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences (CAS) Beijing 100101 China College of Resources and Environment University of Chinese Academy of Sciences Beijing 100190 China College of Plant Science and Technology Huazhong Agricultural University Hubei Wuhan 430070 China Institute of Plateau Biology Lhasa Science and Technology Bureau Lhasa 850011 China

The combination of organic fertilizers (OFs) and chemical fertilizers (CF) is a promising agricultural management strategy to improve soil fertility while mitigating N2O emissions in croplands. However, there is still... 详细信息

The combination of organic fertilizers (OFs) and chemical fertilizers (CF) is a promising agricultural management strategy to improve soil fertility while mitigating N₂O emissions in croplands. However, there is still lacking of in-depth understanding of the effects of different OF and CF blends on N₂O emissions and the underlying drivers. To this end, we conducted a short-term soil incubation to address the influences of partial OF substitutions for CF, i.e., 40% substitution of compost (CP), Yak dung (YD), Qingke straw (QS), and sheep dung (SD) on the processes of nitrification and denitrification in sandy loam soils in the Lhasa Valley. We found that CP, QS, and SD reduced cumulative N₂O emissions by 53.43%, 25.96% and 16.64%, respectively compared to pure chemical fertilizer (N), except YD caused a significant higher in total N₂O emissions. Fertilization treatments primarily regulate potential N₂O emissions by affecting denitrification processes. While ammonia-oxidizing archaea (AOA amoA) could be the main driver of nitrification, and nirS abundance explained most of the cumulative N₂O emissions. In addition, NO₃⁻–N tends to accumulate in the farmland soils, indicating an increase in the risk of leaching and nutrient loss. Overall, soil N₂O emission reduction was favored by applying partial organic fertilizer substitution especially after through compost. Co-composting of animal manure and crop residue has more impressive potential for mitigating farmland N₂O emissions. © The Author(s) 2025.

关键词： Denitrification Microbial gene abundance N2O emissions Nitrification Partial organic substitution Soil incubation

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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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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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Revegetation with artificial plants improves topsoil hydrological properties but intensifies deep-soil drying in northern Loess Plateau,China

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Journal of Arid Land 2018年第3期10卷 335-346页

作者： ZHANG Qingyin JIA Xiaoxu ZHAO Chunlei SHAO Ming'an State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F University Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences

Knowledge about the effects of vegetation types on soil properties and on water dynamics in the soil profile is critical for revegetation strategies in water-scarce regions, especially the choice of vegetation type and human management measures. We focused on the analysis of the effects of vegetation type on soil hydrological properties and soil moisture variation in the 0–400 cm soil layer based on a long-term（2004―2016） experimental data in the northern Loess Plateau region, China. Soil bulk density（BD）, saturated soil hydraulic conductivity（Ks）, field capacity（FC） and soil organic carbon（SOC） in 2016, as well as the volumetric soil moisture content during 2004–2016, were measured in four vegetation types, i.e., shrubland（korshinsk peashrub）, artificial grassland（alfalfa）, fallow land and cropland（millet or potato）. Compared with cropland, revegetation with peashrub and alfalfa significantly decreased BD and increased Ks, FC, and SOC in the 0–40 cm soil layer, and fallow land significantly increased FC and SOC in the 0–10 cm soil layer. Soil water storage（SWS） significantly declined in shrubland and grassland in the 40–400 cm soil layer, causing severe soil drought in the deep soil layers. The study suggested that converting cropland to grassland（alfalfa） and shrubland（peashrub） improved soil-hydrological properties, but worsened water conditions in the deep soil profile. However, natural restoration did not intensify deep-soil drying. The results imply that natural restoration could be better than revegetation with peashrub and alfalfa in terms of good soil hydrological processes in the semi-arid Loess Plateau region.

关键词： soil drying soil hydrological property soil moisture vegetation restoration Loess Plateau

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