检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

赣南稀土尾矿山土体硝态氮累积特征研究

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

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

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2023年第5期33卷 800-807页

作者： Yue zhao jinling yang Nan JIA Yufang SUN Zhe XU {3. zhang 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

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

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2017年第4期27卷 681-693页

作者： SONG Xiaodong LIU Feng zhang ganlin LI Decheng zhao Yuguo yang {3. 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

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

在线全文

学校读者我要写书评

暂无评论

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 {3. 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 22 km^2） in the zhangye 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 2012,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 25% 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

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

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2016年第5期26卷 699-708页

作者： yang Renmin LIU Feng zhang ganlin zhao Yuguo LI Decheng yang jinling 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. 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

Vertical distribution and storage of soil organic and inorganic carbon in a typical inland river basin,Northwest China

在线全文

学校读者我要写书评

暂无评论

Journal of Arid Land 2018年第2期10卷 183-201页

作者： yang Fan HUANG Laiming yang Renmin yang Fei LI Decheng {3. Yuguo yang jinling LIU Feng zhang ganlin State Key Laboratory of soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China University of Chinese academy of sciences Beijing 100049China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Knowledge of soil carbon（C） distribution and its relationship with the environment can improve our understanding of its biogeochemical cycling and help to establish sound regional models of C cycling. However, such knowledge is limited in environments with complex landscape configurations. In this study, we investigated the vertical distribution and storage of soil organic carbon（SOC） and soil inorganic carbon（SIC） in the 10 representative landscapes（alpine meadow, subalpine shrub and meadow, mountain grassland, mountain forest, typical steppe, desert steppe, Hexi Corridor oases cropland, Ruoshui River delta desert, Alxa Gobi desert, and sandy desert） with contrasting bioclimatic regimes in the Heihe River Basin, Northwest China. We also measured the 87 Sr/86 Sr ratio in soil carbonate to understand the sources of SIC because the ratio can be used as a proxy in calculating the contribution of pedogenic inorganic carbon（PIC） to total SIC. Our results showed that SOC contents generally decreased with increasing soil depth in all landscapes, while SIC contents exhibited more complicated variations along soil profiles in relation to pedogenic processes and parent materials at the various landscapes. There were significant differences of C stocks in the top meter among different landscapes, with SOC storage ranging from 0.82 kg C/m^2 in sandy desert to 50.48 kg C/m^2 in mountain forest and SIC storage ranging from 0.19 kg C/m^2 in alpine meadow to 21.91 kg C/m^2 in desert steppe. SIC contributed more than 75% of total C pool when SOC storage was lower than 10 kg C/m^2, and the proportion of PIC to SIC was greater than 70% as calculated from Sr isotopic ratio, suggesting the critical role of PIC in the C budget of this region. The considerable variations of SOC and SIC in different landscapes were attributed to different pedogenic environments resulted from contrasting climatic regimes, parent materials and vegetation types. This study provides an evidence for a general t

关键词： Heihe River Basin arid ecosystem soil landscape pedogenesis pedogenic carbonate SOC CaCO3

Content, Density, Illuviation Mode and Depth of CaCO<sub>3.lt;/sub>in soils of Semiarid-Arid Qilian Mountains—An Altitude Sequence Study of the Hulugou Watershed

在线全文

学校读者我要写书评

暂无评论

Agricultural sciences 2017年第6期8卷 479-491页

作者： Ka Lin Decheng Li ganlin zhang Yuguo zhao {3. yang Feng Liu Xiaodong Song State Key Laboratory of soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing China University of the Chinese academy of sciences Beijing China

The parental material of soils in the Qilian Mountains of northwest China is mainly aeolian loess containing CaCO3.which may remain in soils under the semiarid-arid climate. To disclose the CaCO3.characteristics change with the altitude and the terrain attributes, we surveyed 18 soil profiles in an altitude sequence from 3.76 m to 4510 m in the Hulugou Watershed in the Qilian Mountains, measured CaCO3.contents of all genetic horizon samples, analyzed the densities, illuviation modes and depths of CaCO3.in the profiles, extracted values of the terrain attributes of the profiles including altitude slope, aspect, plane curvature, profile curvature and terrain wetness index (TWI) from the 90 m resolution SRTM3.DEM data on ArcGIS 9.3.platform. We found that CaCO3.weighted content of the profiles ranged from 1.3. g·kg-1 to 93.09 g·kg-1, CaCO3.density from 0.05 kg/m2 to 75.69 kg/m2, CaCO3.illuviation depth from 12 cm to 54 cm. CaCO3.illuviation modes could be divided into three types, i.e., no illuviation mode in which the profile has only A horizon or CaCO3.content -1, middle illuviation mode in which CaCO3.accumulated in a middle horizon, and down illuviation mode in which CaCO3.content increases with the depth. CaCO3.weighted content, density and illuviation depth had significant correlation with certain terrain attributes. In general, the altitude sequence is an effective way to study CaCO3.characteristics in the alpine region, and the data of terrain attributes which can influence the precipitation and its redistribution in soil are potential in predicting soil CaCO3.characteristics in the alpine region.

关键词： CaCO3 Altitude Sequence Terrain Attributes The Hulugou Watershed The Qilian Mountains

Change of Tillage Layer Thickness of Farmland in Anhui Province of Eastern China

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Agricultural sciences 2014年第5期5卷 394-401页

作者： Yuxin Ma Decheng Li ganlin zhang Xusheng Li Yuguo zhao {3. yang Feng Liu Mingsong zhao Shanquan Li Changlong Wei Fan yang Laiming Huang School of Geographic and Oceanographic sciences Nanjing University Nanjing China State Key Laboratory of soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing China State Key Laboratory of soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing China School of Geographic and Oceanographic sciences Nanjing University Nanjing China

Tillage layer thickness (TLT) of farmland could be regarded as one of physical indexes in assessing soil productivity and quality. In recent years, tillage layer shallowing was found in China in various regions, mainly due to the adoption of non-tillage or rotary tillage practices, but only little rough and non-quantitative information is available so far on the issue. This research took Anhui, a typical agricultural province in Eastern China as an example and compared the TLTs of 87 typical profiles on provincial scale and 210 on county scale from 1980s to 2010s. The results showed that TLTs of 3.7% and 17.2% of samples in 1980s and 2010s respectively were larger than 20 cm. From 1980s to 2010s the mean TLT increased from 16.3.to 17.4 cm on the provincial scale and from 15.0 to 15.5 cm on the county scale respectively. In the middle and southern regions the mean TLTs increased by 0.4-0.7 cm on the provincial scale and 0.3.3.2 cm on the county scale respectively, but decreased by 2.0 cm in northern region on the county scale. The mean TLT increased by 0.8 cm for paddy-field and 1.4 cm for dry-land on the provincial scale. TLT was influenced comprehensively by the factors of soil texture, the depth of rotary tillage and the farming positivity of the farmers. Generally, TLT of farmland with coarse soil texture was higher than that of farmland with fine soil texture, in 1980s TLT in region of poor-economic condition usually was deeper than in region of good-economic condition, and the adoption of rotary tillage led widely TLTs of farmlands to about 15 cm in 2010s.

关键词： Tillage Layer Thickness Farmland Influential Factor Anhui Province

模拟酸雨淋溶下不同母质发育雏形土矿物风化中的盐基离子与硅计量关系

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

土壤学报 2023年第5期60卷 1456-1467页

作者：赵越杨金玲许哲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 湖泊与环境国家重点实验室(中国科学院地理与湖泊研究所) 南京210008

土壤矿物风化过程中释放的盐基离子(BC)与硅(Si)的比值(BC︰Si)是定量评估土壤矿物风化对土壤酸化过程缓冲作用的基础,是准确估算当前环境下土壤酸化速率的依据。本研究以云母片岩、片麻岩和安山岩3.母质发育的湿润雏形土为研究对象,... 详细信息

土壤矿物风化过程中释放的盐基离子(BC)与硅(Si)的比值(BC︰Si)是定量评估土壤矿物风化对土壤酸化过程缓冲作用的基础,是准确估算当前环境下土壤酸化速率的依据。本研究以云母片岩、片麻岩和安山岩3.母质发育的湿润雏形土为研究对象,测定了其土壤物理、化学和矿物学性质。通过洗脱实验除去土壤交换性盐基以消除土壤胶体吸附的交换性盐基离子对矿物风化计量关系的影响,再利用模拟酸雨淋溶实验,采用Batch方法获取3.不同母质发育土壤的盐基离子和硅的释放量,进一步估算BC︰Si值。结果表明,由于母岩不同,土壤黏粒、pH、有机质、交换性盐基(K^(+)、Na^(+)、Ca^(2+)和Mg^(2+))、阳离子交换量(CEC)和土壤矿物含量存在差异。在模拟酸雨淋溶实验条件下,未洗脱盐基土壤的BC︰Si值为洗脱盐基土壤的3.以上,因此只有洗脱土壤交换性盐基才能获得来自风化过程的BC︰Si值。同一母质发育土壤的腐殖质表层(Ah)BC︰Si最小,母质层(C)最大。不同母质发育土壤的BC︰Si值表现为:片麻岩>云母片岩>安山岩,土壤中斜长石、伊利石、绿泥石和蛭石的含量控制了各自BC︰Si的大小。因此,不同起源母质发育的雏形土应在得到各自相应风化计量关系的基础上,才可准确评估其对酸化过程的响应程度。该成果可为区域土壤酸化速率评价提供数据支撑。

关键词：计量关系矿物风化母质土壤酸化土壤发生地球化学