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Spatio-Temporal Variability of Soil Salinity in Alluvial Plain of the Lower Reaches of the Yellow River——A Case Study

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Pedosphere 2011年第6期21卷 793-801页

作者： LI Kai-Li CHEN Jie tan man-zhi ZHAO Bing-Zi MI Shu-Xiao SHI Xue-Zheng State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Graduate University of Chinese Academy of Sciences Beijing 100049 （China） Department of Geography Jiangsu Institute of Education Nanjing 210013 （China） School of Water Conservation and Environment Zhengzhou University Zhengzhou 450000 （China）

Soil salinity and hydrologic datasets were assembled to analyze the spatio-temporal variability of salinization in Fengqiu County, Henan Province, China, in the alluvial plain of the lower reaches of the Yellow River. The saline soil and groundwater depth data of the county in 1981 were obtained to serve as a historical reference. Electrical conductivity （EC） of 293 surface soil samples taken from 2 kin x 2 km grids in 2007 and 4{） soil profiles acquired in 2（108 was analyzed and used for comparative mapping. Ordinary kriging was applied to predict EC at unobserved locations to derive the horizontal and vertical distribution patterns and variation of soil salinity. Groundwater table data from 22 observation wells in 2008 were collected and used as input for regression kriging to predict the maximum groundwater depth of the county in 2008. Changes in the groundwater level of Fengqiu County in 27 years from 1981 to 2008 was calculated. Two quantitative criteria, the mean error or bias （ME） and the mean squared error （MSE）, were computed to assess the estimation accuracy of the kriging predictions. The results demonstrated that the soil salinity in the upper soil layers decreased dramatically and the taxonomically defined saline soils were present only in a few micro-landscapes after 27 years. Presently, the soils with relatively elevated salt content were mainly distributed in depressions along the Yellow River bed. The reduction in surface soil salinity corresponded to the locations with deepened maximum groundwater depth. It could be concluded that groundwater table recession allowed water to move deeper into the soil profile, transporting salts with it, and thus played an important role in reducing soil salinity in this region. Accumulation of salts in the soil profiles at various depths below the surface indicated that secondary soil salinization would occur when the groundwater was not controlled at a safe depth.

关键词： electrical conductivity groundwater table kriging salinization salt content

Effect of Soil Sampling Density on Detected Spatial Variability of Soil Organic Carbon in a Red Soil Region of China

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Pedosphere 2011年第2期21卷 207-213页

作者： YU Dong-Sheng ZHANG Zhong-Qi YANG Hao SHI Xue-Zheng tan man-zhi SUN Wei-Xia WANG Hong-Jie College of Geographical Sciences Nanjing Normal University Nanjing 210046 (China) State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008(China) Graduate University of Chinese Academy of Sciences Beijing 100099 (China) Xuzhou Normal Unsiversity Xuzhou 221116 (China)

Spatial variability of soil organic carbon (SOC) of different land use patterns and soil types was examined in a county-wide red soil region of South China,using six sampling densities,14,34,68,130,255,and 525 samples designed by the method of grid sampling in 6 different grid sizes,labeled as D14,D34,D68,D130,D255,and D525,*** results showed that the coefficients of variation (CVs) of SOC decreased gradually from 62.8% to 47.4% with the increase in soil sampling *** SOC CVs in the paddy field change slightly from 30.8% to 28.7%,while those of the dry farmland and forest land decreased remarkably from 58.1% to 48.7% and from 99.3% to 64.4%,*** SOC CVs of the paddy soil change slightly,while those of red soil decreased remarkably from 82.8% to 63.9%.About 604,500,and 353 (P tant effect on the detection of SOC variability in the county-wide region,the equal interval grid sampling was not efficient enough,and the respective CV of each land use or soil type should be fully considered when determining the sampling number in the future.

关键词： coefficient of variation county-wide region grid sampling land use soil type

Soil degradation: a global problem endangering sustainable development

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Journal of Geographical Sciences 2002年第2期12卷 120-129页

作者： Chen Jie Chen Jing-zhang tan man-zhi Gong Zi-tong Institute of Soil Science CAS Nanjing 210008

Soil degradation, defined as lowering and losing of soil functions, is becoming more and more serious worldwide in recent decades, and poses a threat to agricultural production and terrestrial ecosystem. It is estimated that nearly 2 billion ha of soil resources in the world have been degraded, namely approximately 22% of the total cropland, pasture, forest, and woodland. Globally, soil erosion, chemical deterioration and physical degradation are the important parts amongst various types of soil degradation. As a natural process, soil degradation can be enhanced or dampened by a variety of human activities such as inappropriate agricultural management, overgrazing, deforestation, etc. Degraded soil means less food. As a result of soil degradation, it is estimated that about 11.9-13.4% of the global agricultural supply has been lost in the past five decades. Besides, soil degradation is also associated with off-site problems of sedimentation, climate change, watershed functions, and changes in natural habitats leading to loss of genetic stock and biodiversity. Therefore, it is essential to combat soil degradation at different levels and scales worldwide, not only for food security and ecological health, but also for the guarantee of global sustainable development.

关键词： soil soil degradation erosion food security sustainable development

Regional Diferences in the Efect of Climate and Soil Texture on Soil Organic Carbon

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Pedosphere 2013年第6期23卷 799-807页

作者： WANG Mei-Yan SHI Xue-Zheng YU Dong-Sheng XU Sheng-Xiang tan man-zhi SUN Wei-Xia ZHAO Yong-Cun State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of Sciences Graduate University of Chinese Academy of Sciences

The agricultural soil carbon pool plays an important role in mitigating greenhouse gas emission ana unaerstanamg the son orgamc carbon-climate-soil texture relationship is of great significance for estimating cropland soil carbon pool responses to climate change. Using data from 900 soil profiles, obtained from the Second National Soil Survey of China, we investigated the soil organic carbon （SOC） depth distribution in relation to climate and soil texture under various climate regimes of the cold northeast region （NER） and the warmer Huang-Huai-Hai region （HHHR） of China. The results demonstrated that the SOC content was higher in NER than in HHHR. For both regions, the SOC content at all soil depths had significant negative relationships with mean annual temperature （MAT）, but was related to mean annual precipitation （MAP） just at the surface 0-20 cm. The climate effect on SOC content was more pronounced in NER than in HHHR. Regional differences in the effect of soil texture on SOC content were not found. However, the dominant texture factors were different. The effect of sand content on SOC was more pronounced than that of clay content in NER. Conversely, the effect of clay on SOC was more pronounced than sand in HHHR. Climate and soil texture jointly explained the greatest SOC variability of 49.0% （0-20 cm） and 33.5% （20-30 cm） in NER and HHHR, respectively. Moreover, regional differences occurred in the importance of climate vs. soil texture in explaining SOC variability. In NER, the SOC content of the shallow layers （0-30 cm） was mainly determined by climate factor, specifically MAT, but the SOC content of the deeper soil layers （30-100 cm） was more affected by texture factor, specifically sand content. In HHHR, all the SOC variability in all soil layers was predominantly best explained by clay content. Therefore, when temperature was colder, the climate effect became stronger and this trend was restricted by soil depth. The regional differences and soil depth

关键词： climate change cropland soil carbon pool soil depth temperature

Spatial Prediction of Heavy Metal Pollution for Soils in Peri-Urban Beijing, China Based on Fuzzy Set Theory

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Pedosphere 2006年第5期16卷 545-554页

作者： tan man-zhi XU Fang-Ming CHEN Jie ZHANG Xue-Lei CHEN Jing-Zhong State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Graduate school of the Chinese Academy of Sciences Beijing 100039 Chengdu University of Technology Chengdu 610059 （China） Nanjing Station of Soil and Fertilizer Nanjing 210036 （China）

Fuzzy classification combined with spatial prediction was used to assess the state of soil pollution in the peri-urban Beijing area. Total concentrations of As, Cr, Cd, Hg, and Pb were determined in 220 topsoil samples （0-20 cm） collected using a grid design in a study area of 2 600 kin2. Heavy metal concentrations were grouped into three classes according to the optimum number of classes and fuzziness exponent using the fuzzy comean （FCM） algorithm. Membership values were interpolated using ordinary kriging. The polluted soils of the study area induced by the measured heavy metals were concentrated in the northwest corner and eastern part, especially the southeastern part close to the urban zone, whereas the soils free of pollution were mainly distributed in the southwestern part. The soils with potential risk of heavy metal pollution were located in isolated spots mainly in the northern part and southeastern corner of the study region. The FCM algorithm combined with geostatistical techniques, as compared to conventional single geostatistical kriging methods, could produce a prediction with a quantitative uncertainty evaluation and higher reliability. Successful prediction of soil pollution achieved with FCM algorithm in this study indicated that fuzzy set theory had great potential for use in other areas of soil science.

关键词： continuous classification fuzzy c-means heavy metal soil pollution spatial prediction

Modeling Carbon Dynamics in Paddy Soils in Jiangsu Province of China with Soil Databases Differing in Spatial Resolution

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Pedosphere 2011年第6期21卷 696-705页

作者： XU Sheng-Xiang SHI Xue-Zheng ZHAO Yong-Cun YU Dong-Sheng WANG Shi-Hang ZHANG Li-Ming C. S. LI tan man-zhi State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Graduate University of Chinese Academy of Sciences Beijing 100049 （China） College of Environmental and Resource Sciences Fujian Agriculture and Forestry University Fujian 350002 （China） Institute for the Study of Earth Oceans and Space Complex Systems Research Center University of New Hampshire Durham NH03824 （USA）

A number of process-based models have been developed for quantifying carbon(C)sequestration in *** DeNitrification-DeComposition(DNDC)model was used to simulate and quantify long-term(1980-2008)soil organic carbon(SOC)dynamics in the important rice-producing province,Jiangsu,*** in SOC storages were estimated from two soil databases differing in spatial resolution:a county database consisting of 68 polygons and a soil patch-based database of 701 polygons for all 3.7 Mha of rice fields in *** simulated SOC storage with the coarse resolution county database ranged between 131.0-320.6 Tg C in 1980 and 170.3-305.1 Tg C in 2008,respectively,while that estimated with the fine resolution database was 201.6 and 216.2 Tg C in 1980 and 2008,*** results modeled with the soil databases differing in spatial resolution indicated that using the soil input data with higher resolution substantially increased the accuracy of the modeled results;and when lacking detailed soil datasets,the DNDC model,parameterized with the most sensitive factor(MSF) method to cope with attribute uncertainty,could still produce acceptable results although with deviations of up to 60% for the case study reported in this paper.

关键词： 1:1 000000 soil map C sequestration rate DeNitrification-DeComposition (DNDC) greenhouse gas soil organic carbon (SOC)

土壤模糊隶属度不同数据转换方法及其对空间插值结果的影响

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生态学报 2009年第6期29卷 3147-3153页

作者：檀满枝陈杰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 郑州大学自然资源与生态环境研究所郑州450001

应用模糊c-均值算法对土壤进行连续分类时,其输出的土壤模糊隶属度值具有成分数据的结构特点。直接基于土壤隶属度数据实施普通克里格插值,其空间预测结果缺乏可信度。因此,在进行插值预测之前,必须对土壤模糊隶属度值进行必要的数据转... 详细信息

应用模糊c-均值算法对土壤进行连续分类时,其输出的土壤模糊隶属度值具有成分数据的结构特点。直接基于土壤隶属度数据实施普通克里格插值,其空间预测结果缺乏可信度。因此,在进行插值预测之前,必须对土壤模糊隶属度值进行必要的数据转换。研究采用对数正态变换方法、对称对数比转换方法和非对称对数比转换方法对土壤模糊隶属度值进行数据转换,分析了各种数据转换形式对插值结果及其精度的影响。结果表明,对样点土壤模糊隶属度进行简单对数正态转换,其插值结果空间上任意点的土壤对于不同类别的隶属度之和均不为1,因此这样的插值结果理论上缺乏可行性。数据经非对称对数比转换和对称对数比转换后,插值结果均满足各个位置组分之和为1和非负限制,二者相比,后者对区域总体趋势的反映较前者好,且精度较高。因此,在应用对称对数比方法对样点土壤模糊隶属度值进行数据转换的基础上,应用克里格技术实施空间插值可以获得最佳预测结果。

关键词：土壤模糊隶属度成分数据非对称对数比转换对称对数比转换空间预测

乡村振兴背景下非遗传承人与新乡贤的互构机制——以“撒叶儿嗬”传承现状为中心的考察

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中央民族大学学报（哲学社会科学版） 2021年第4期48卷 123-132页

作者：谭志满湖北民族大学民族学与社会学学院湖北恩施445000

非物质文化遗产保护、传承与创新已嵌入我国的公共文化事业建设、地方经济社会发展和国家话语权提升的进程中,也是我国当前开展乡村文化振兴的重要内容。国家级非物质文化遗产"撒叶儿嗬"是清江中游地区土家族具有代表性的传统文化事项。... 详细信息

非物质文化遗产保护、传承与创新已嵌入我国的公共文化事业建设、地方经济社会发展和国家话语权提升的进程中,也是我国当前开展乡村文化振兴的重要内容。国家级非物质文化遗产"撒叶儿嗬"是清江中游地区土家族具有代表性的传统文化事项。在"撒叶儿嗬"的非遗保护实践中,传承空间从家庭走向社区,传承模式从个人自发参与转变为传承基地组织的系统培训与展演;非遗传承人的角色实现从制度性安排向富有情怀的新乡贤身份的转变。新乡贤作为新时代背景下乡村建设过程中重要的参与主体,是具有乡土情怀、有一定资财和威望的社区能人,在传统文化传承创新中起到引领示范作用。非遗传承人和新乡贤是不同语境中连接官方与民间、国家与社会以及大传统与小传统的地方社会精英,不仅在核心理念、基本目标和实践主体上具有相似性;而且在学术认知、政策框架和社会功能上具有互补性。从个人与社会的关系来看,非遗传承人与新乡贤在理念和实践上相互嵌入、共生互动。实现从国家制度安排下的非遗传承人身份向文化引领型新乡贤角色的转变,有助于解决当前对非遗传承人管理及其作用发挥中存在的问题,提升非物质文化遗产保护在乡村社会的功能性、生活性和生产性,助推非物质文化遗产保护实践与乡村振兴战略整体目标的深度融合。

关键词：非遗保护乡村文化振兴非遗传承人新乡贤

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语言人类学视野下的濒危语言研究

中南民族大学学报（人文社会科学版） 2008年第1期28卷 38-41页

作者：谭志满湖北民族学院民族研究所湖北恩施445000

语言人类学是语言学与人类学相互交叉的一个边缘学科。语言人类学在产生之初主要是对"土著"后进民族的语言文化进行研究。在现阶段,语言人类学主要是对濒危语言的关注,并力图通过对濒危语言的抢救与研究来保存人类语言的多元格局,进而... 详细信息

语言人类学是语言学与人类学相互交叉的一个边缘学科。语言人类学在产生之初主要是对"土著"后进民族的语言文化进行研究。在现阶段,语言人类学主要是对濒危语言的关注,并力图通过对濒危语言的抢救与研究来保存人类语言的多元格局,进而保存人类文化的多样性。在当前濒危语言研究的过程中,人类学的理论与方法对其极具启示意义。

关键词：语言人类学濒危语言民族文化