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Quantitative Relationship Between Land Use and Phosphorus Discharge in Subtropical Hilly Regions of China

Pedosphere 2003年第1期13卷 67-74页

作者： yang jinling and {2. {3. of soil Science, the chinese Academy of sciences, nanjing 2.0008 (China) Institute of soil Science the Chinese Academy of Sciences Nanjing 210008

The increase of phosphorus concentration is a crucial factor causing the eutrophication of water body,while land use has an important impact on agricultural non-point sources (NPS) phosphorus discharge. Sevensites controlling the water in four sub-watersheds and the main exit of the Meicun Watershed of XuanchengCounty, Anhui Province, were investigated by dynamic monitoring of stream water and nutrient discharge,integrating interpretation of aerial image and GIS analysis to find out how the land use affects phosphorusloss with stream water in typical agriculture-forest watershed in subtropical China. These monitored sitesare different in structure of land use. Phosphorus concentration of the stream water was analyzed everyweek and at the next day of rainfall. The velocity of flow was measured by kinemometer to calculatethe runoff flux and phosphorus discharge. The results showed that the runoff flux and the discharges ofdissolved phosphorus (DP), particle-associated phosphorus (PAP) and total phosphorus (TP) had significantexponential relationships with the area percentages of forest, pond and paddy field. There existed a significantlinear relationship between the TP and PAP concentrations in stream water and the area percentages of forest,pond and paddy field, and the discharge of PAP was also significantly linearly correlated with the dischargeof suspended soil particles. There was a logarithmic linear relationship between DP and PAP discharges. Thestudy indicated that the adjustment of land use patterns and construction of ecologically sound landscapewould be an important measure to reduce the runoff discharge of phosphorus. The results would be veryuseful in building the best management practices (BMPs) of agricultural watershed in subtropics.

关键词： land use phosphorus runoff watershed

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Nutrient Discharges from a Typical Watershed in the Hilly Area of Subtropical China

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Pedosphere 2003年第1期13卷 23-30页

作者： zhang GANLIN, yang {2. and ZHAO YUGUOInstitute of {3. Science, the chinese Academy of sciences, nanjing 2.0008 (China) Institute of soilScience the Chinese Academy of sciences Nanjing 210008

Agriculture is still the biggest contributor of non-point source (NPS) pollution to water bodies andrunoff discharges of nutrients and other chemicals are one of the most important pathways. This studywas conducted during 1998～1999 in a typical watershed with complex agriculture and forestry systems aswell as dotted farmer villages, in a transitional region between the mid- and northern subtropical zones ofChina. Continuous sampling of stream water was performed regularly at a weekly frequency, with additionalsampling after all major rainfall events. The discharges of N and P nutrients and suspended materials weremeasured and the total and area-averaged annual discharges of all components were calculated. The resultsshowed an uneven seasonal distribution of nutrient discharges with summer storms contributing most tothe total fluxes. This study demonstrated a high dependence of runoff volume on rainfall but the overallrunoff coefficients were dependent on land use type and watershed size. The area-averaged annual dischargesvaried greatly among the sub-watersheds with different sizes and land use structures. This is the first studyestimating the area-averaged annual discharges of N and P in the hilly areas of subtropical China, which were1.5 g m-2.a-1 and 0.1 g m-2.a-1, respectively, providing important reference values for the assessment ofregional agricultural non-point source pollution.

关键词： discharge nutrients runoff subtropical china watershed

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赣南稀土尾矿山土体硝态氮累积特征研究

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土壤学报 2024年第3期61卷 727-736页

作者：许哲杨金玲赵越张甘霖土壤与农业可持续发展国家重点实验室(中国科学院南京土壤研究所) 南京210008 中国科学院大学北京100049 中国科学院南京地理与湖泊研究所南京210008

稀土开采会造成大量浸矿剂(硫酸铵)残留在土壤中,高浓度铵态氮(NH_(4)^(+)-N)可能在生物化学作用下转化为硝态氮(NO_(3.^(-)-N)。为探明NO_(3.^(-)-N在稀土尾矿山土体内的含量及影响因素,明确硝酸盐污染程度,本研究选择赣南地区一个离... 详细信息

稀土开采会造成大量浸矿剂(硫酸铵)残留在土壤中,高浓度铵态氮(NH_(4)^(+)-N)可能在生物化学作用下转化为硝态氮(NO_(3.^(-)-N)。为探明NO_(3.^(-)-N在稀土尾矿山土体内的含量及影响因素,明确硝酸盐污染程度,本研究选择赣南地区一个离子型稀土原地浸矿尾矿山,由表土分层采样至基岩面,并分析土壤NO_(3.^(-)-N及相关的理化性质。研究结果表明,尾矿山土体NO_(3.^(-)-N含量变异范围非常大(2.80~193.99 mg·kg^(–1)),其平均值为46.3.±55.16 mg·kg^(–1),表层土壤NO_(3.^(-)-N含量范围为2.89~6.75 mg·kg^(–1),与自然土壤相近;表层以下土壤NO_(3.^(-)-N含量明显高于自然土壤。尾矿山土体深部含矿层土壤NO_(3.^(-)-N含量明显高于表层,NO_(3.^(-)-N含量随深度的分布规律与自然土壤相反,这是矿体部分残留大量浸矿剂造成的。土壤NH_(4)^(+)-N含量主导了NO_(3.^(-)-N的产生量,但NO_(3.^(-)-N在土体不同深度、山体不同部位的累积量还受降雨淋溶及NO_(3.^(-)-N迁移过程的控制。开采结束4年后,尾矿山内累积的NO_(3.^(-)-N仍不断向环境中释放。长期来看,尾矿山土壤中富集的NH_(4)^(+)-N将不断转化为NO_(3.^(-)-N并随水迁移,持续威胁生态环境及人类健康。本研究可为稀土原地浸矿场地土壤及下游水体污染的评价和治理提供理论基础与科学支撑。

关键词：氮转化硝态氮分布硝态氮迁移离子型稀土矿区土壤

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Improvement of modelling accuracy by using high resolution soil data in a coupled surface-subsurface water flow model

Improvement of modelling accuracy by using high resolution s...

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2.11 World Congress on Engineering and Technology(CET 2.11)

作者： Qi zhang State Key Laboratory of Lake Science and Environment nanjing Institute of Geography and Limnology {2. Academy of {3. nanjing 2.0008 China jinling yang Institute of soil Science {2. Academy of {3. nanjing 2.0008 China

This paper tested the effects of refined soil property on the hydrological modelling results, exemplified in the surface runoff-groundwater coupled model for Xitiaoxi catchment, Lake Taihu basin, by extending the previous study where a relatively coarse soil map was used. This study finds that the refined soil property, associated with a finer model grid size significantly improves the accuracy in modelling the stream flow for dry seasons, when the groundwater base flow （groundwater discharged to rivers） dominates the stream flow. Since the groundwater base flow is highly dependent on the soil water percolation processes, the accurate simulation of base flow requires an accurate representation of the soil property and soil water processes. This finding implies that the soil resolution may affect the partitioning of surface and subsurface water flow, and should be appropriately considered in coupled simulation of surface and subsurface water flow, especially for the cases that stream flow simulations for dry seasons demand for a high accuracy.

关键词： soil resolution surface-subsurface water flow modelling accuracy dry seasons WATLAC Xitiaoxi catchment

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Chemistry and source identification of wet precipitation in a rural watershed of subtropical China

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chinese Journal Of Geochemistry 2012年第4期31卷 347-354页

作者： HUANG Laiming yang jinling {2. Ganlin State Key Laboratory of Sod and Sustamable Agrtculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Graduate University of chinese Academy of sciences Beijing 100049China

South China is one of the regions severely suffering from acid rain in the ***,few systematic studies of rural precipitation chemistry have been performed in comparison with the extensive studies on their urban counterparts of this *** order to characterize the current acid rain status and identify its possible sources in the rural area of South China,we analyzed precipitation collected event by event from a rural forested watershed in southern Anhui Province between March 2.07 and February *** results showed that the concentrations of major ions within precipitation in the studied rural area were significantly lower than those reported for the urban areas of the same latitude in ***,the precipitation acidity(with an average pH value of 4.49) and the frequency of acid rain(95%) were considerably *** relatively high ratio of(SO42. NO 3./(Ca2. +NH4+) was the main cause of acid rain in this rural area,as SO 2.and NO x were the main precursors of acid rain,while Ca2. and NH4+acted as the dominant neutralizers to the *** identification indicated that Ca2. and Mg2. mainly were derived from alkaline dust,SO42.NO 3.and NH4+originated mainly from anthropogenic sources such as industrial and agricultural activities,most Na +,Cl,K + and some of Mg2. were derived from the *** results suggested that the major ions within precipitation in the rural area of South China were related to the meso-scale and long-range transport of particles and aerosols in the air.

关键词：农村地区降水化学分水岭源识别中国沉淀亚热带湿法

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Multi-Source Characteristics of Atmospheric Deposition in nanjing,China,as Controlled by East Asia Monsoons and Urban Activities

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Pedosphere 2016年第3期26卷 374-385页

作者： LI Shanquan zhang Ganlin yang {2. JIA Nan State Key Laboratory of soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China) University of chinese Academy of sciences Beijing 100049 (China)

Atmospheric deposition, a major pathway of metals entering into soils, plays an important role in soil environment, especially in urban regions where a large amount of pollutants are emitted into atmosphere through various sources. In order to understand the characteristics of atmospheric deposition in urban area and its relation with natural and anthropogenic sources, a three-year study of atmospheric deposition at three typical sites, industrial zone(IN), urban residential area(RZ) and suburban forested scenic area(FA),was carried out in {2., a metropolitan city in eastern China from 2.05 to 2.07. The bulk deposition rate and element composition of atmospheric deposition varied spatio-temporally in the urban zones of {2.. The concentrations of Cu, Zn, Pb and Ca in the atmospheric deposits were strongly enriched in the whole {2. region; however, anthropogenic pollutants in atmospheric deposits were diluted by the input of external mineral dust transported from northwestern China. Source apportionment through principal component analysis(PCA) showed that the background atmospheric deposition at the FA site was the combination of external aerosol and local emission sources. The input of long-range transported Asian dust had an important influence on the urban background deposition, especially in spring when the continental dust from the northwestern China prevailed. Marine aerosol source was observed in summer and autumn, the seasons dominated by summer monsoon in {2.. In contrast, the contribution of local anthropogenic emission source was constant regardless of seasons. At the RZ and IN sites, the atmospheric deposition was more significantly affected by the nearby human activities than at the FA site. In addition, different urban activities and both the winter and summer Asian monsoons had substantial impacts on the characteristics of dust deposition in urban {2..

关键词： aerosol anthropogenic pollutants Asian dust metals source apportionment urban environment

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Mapping soil Texture Based on Field soil Moisture Observations at a High Temporal Resolution in an Oasis Agricultural Area

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Pedosphere 2016年第5期26卷 699-708页

作者： yang Renmin LIU Feng zhang Ganlin ZHAO Yuguo LI Decheng yang {3. yang Fei yang Fan State Key Laboratory of soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) University of chinese Academy of sciences Beijing 100049(China)

Due to the almost homogeneous topography in low relief areas, it is usually difficult to make accurate predictions of soil properties using topographic covariates. In this study, we examined how time series of field soil moisture observations can be used to estimate soil texture in an oasis agricultural area with low relief in the semi-arid region of northwest China. Time series of field-observed soil moisture variations were recorded for 13.4}h beginning at the end of an irrigation event during which the surface soil was *** correlation between two time-adjacent soil moisture conditions was used to select the factors for fuzzy c-means clustering. In each of the ten generated clusters, soil texture of the soil sample with the maximum fuzzy membership value was taken as the cluster centroid. Finally, a linearly weighted average was used to predict soil texture from the centroids. The results showed that soil moisture increased with the increase of clay and silt contents, but decreased with the increase of sand content. The spatial patterns of soil moisture changed during the entire soil drying phase. We assumed that these changes were mainly caused by spatial heterogeneity of soil texture. A total of 64 independent samples were used to evaluate the prediction accuracy. The root mean square error(RMSE)values of clay, silt and sand were 1.63. 2.81 and 3.71, respectively. The mean relative error(RE) values were 9.57% for clay, 3.77% for silt and 12.83. for sand. It could be concluded that the method used in this study was effective for soil texture mapping in the low-relief oasis agricultural area and could be applicable in other similar irrigation agricultural areas.

关键词： digital soil mapping fuzzy c-means clustering low relief particle-size distribution semi-arid region water content

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Stoichiometry of base cations and silicon during weathering of a deep soil profile derived from granite

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Pedosphere 2023年第5期33卷 800-807页

作者： Yue ZHAO jinling yang Nan JIA Yufang SUN Zhe XU Ganlin {2. State Key Laboratory of soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China University of chinese Academy of sciences Beijing 100081China State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China soil&Environment Analysis Center Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China

Evaluation of the stoichiometry of base cations(BCs,including K^(+),Na^(+),Ca^(2.),and Mg^(2.))and silicon(Si)(BCs:Si)during soil mineral weathering is essential to accurately quantify soil acidification *** aim of this study was to explore the differences and influencing factors of BCs:Si values of different soil genetic horizons in a deep soil profile derived from granite with different extents of mineral *** type was typic acidi-udic *** samples were collected from Guangzhou,China,which is located in a subtropical *** ensure that the BCs and Si originated from the mineral weathering process,soil exchangeable BCs were washed with an elution *** BCs:Si values during weathering were obtained through a simulated acid rain leaching experiment using the batch *** showed that soil physical,chemical,and mineralogical properties varied from the surface horizon to saprolite in the soil *** BCs:Si values of soil genetic horizons during weathering were 0.3.*** BCs:Si value was 1.7 in the surface horizon(A),1.1–3.7 in the argillic horizon(Bt),and 0.3.0.4 in the cambic(Bw)and transition(BC)horizons,as well as in horizon C(saprolite).The general pattern of BCs:Si values in the different horizons was as follows:Bt>A>Bw,BC,and *** BCs:Si values were influenced by weathering intensity,they did not correlate with the chemical index of alteration(CIA).The release amounts of Si and BCs are the joined impact of soil mineral composition and physical and chemical properties.A comprehensive analysis showed that the BCs:Si values of the soil derived from granite in this study were a combined result of the following factors:soil clay,feldspar,kaolinite,organic matter,pH,and *** main controlling factors of BCs:Si in soils of different parent material types require extensive *** wide variance of BCs:Si values in the deep soil profile indicated that H+consumed by soil mineral weathering was very dissimilar i

关键词： mineral weathering soil acidification rate soil evolution soil genesis soil geochemistry weathered sequence

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Mapping soil Organic Carbon Using Local Terrain Attributes： AComparison of Different Polynomial Models

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Pedosphere 2017年第4期27卷 681-693页

作者： SONG Xiaodong LIU Feng zhang Ganlin LI Decheng ZHAO Yuguo yang {2. State Key Laboratory of soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China

Local terrain attributes,which are derived directly from the digital elevation model,have been widely applied in digital soil *** study aimed to evaluate the mapping accuracy of soil organic carbon(SOC) concentration in 2.zones of the Heihe River in China,by combining prediction methods with local terrain attributes derived from different polynomial *** prediction accuracy was used as a benchmark for those who may be more concerned with how accurately the variability of soil properties is modeled in practice,rather than how morphometric variables and their geomorphologic interpretations are understood and *** this study,2.neighborhood types(square and circular) and 6 representative algorithms(Evans-Young,Horn,Zevenbergen-Thorne,Shary,Shi,and Florinsky algorithms) were *** general,3. combinations of first-and second-order derivatives were produced as candidate predictors for soil mapping using two mapping methods(i.e.,kriging with an external drift and geographically weighted regression).The results showed that appropriate local terrain attribute algorithms could better capture the spatial variation of SOC concentration in a region where soil properties are strongly influenced by the *** the different combinations of firstand second-order derivatives used,there was a best combination with a more accurate *** different prediction methods,the relative improvement in the two zones varied between 0.3.% and 9.68%.The SOC maps resulting from the higher-order algorithms(Zevenbergen-Thorne and Florinsky) yielded less interpolation ***,it was concluded that the performance of predictive methods,which incorporated auxiliary variables,could be improved by attempting different terrain analysis algorithms.

关键词： cross-validation digital soil mapping geographically weighted regression kriging with an external drift mapping accuracy

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Modeling spatio-temporal distribution of soil moisture by deep learning-based cellular automata model

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Journal of Arid Land 2016年第5期8卷 734-748页

作者： SONG Xiaodong zhang Ganlin LIU Feng LI Decheng ZHAO Yuguo yang {2. State Key Laboratory of soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of Sciences

soil moisture content （SMC） is a key hydrological parameter in agriculture,meteorology and climate change,and understanding of spatio-temporal distributions of SMC in farmlands is important to address the precise irrigation ***,the hybrid interaction of static and dynamic environmental parameters makes it particularly difficult to accurately and reliably model the distribution of *** present,deep learning wins numerous contests in machine learning and hence deep belief network （DBN） ,a breakthrough in deep learning is trained to extract the transition functions for the simulation of the cell state *** this study,we used a novel macroscopic cellular automata （MCA） model by combining DBN to predict the SMC over an irrigated corn field （an area of 2. km^2. in the {3.ye oasis,Northwest *** and dynamic environmental variables were prepared with regard to the complex hydrological *** widely used neural network,multi-layer perceptron （MLP） ,was utilized for comparison to *** hybrid models （MLP-MCA and DBN-MCA） were calibrated and validated on SMC data within four months,*** to September 2.12.which were automatically observed by a wireless sensor network （WSN） .Compared with MLP-MCA,the DBN-MCA model led to a decrease in root mean squared error （RMSE） by 18%.Thus,the differences of prediction errors increased due to the propagating errors of variables,difficulties of knowing soil properties and recording irrigation amount in *** sequential Gaussian simulation （s Gs） was performed to assess the uncertainty of soil moisture *** with a threshold of SMC for each grid cell,the local uncertainty of simulated results in the post processing suggested that the probability of SMC less than 2.% will be difference in different areas at different time *** current results showed that the DBN-MCA model performs better than the MLP-MCA model,and the DBN-MCA model provides a powerful tool for predicti

关键词： soil moisture soil moisture sensor network macroscopic cellular automata (MCA) deep belief network (DBN) multi-layer perceptron (MLP) uncertainty assessment hydropedology

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