中国农业科学院农业信息研究所 中国农学会
Agricultural Information Institute of CAAS China Association of Agricultural Science Societies
En
Ch
中国农业科学院农业信息研究所 中国农学会 主办

AI检索

订阅

返回顶部
当前位置: 首页 > 文章 > 确定~(137)Cs背景值所需的采样点数与采样面积 核农学报 2009,23 (3) 130-134
Position: Home > Articles > SAMPLING NUMBERS AND AREA FOR THE CONFIRMATION OF ~(137)Cs REFERENCE INVENTORY Journal of Nuclear Agricultural Sciences 2009,23 (3) 130-134

确定~(137)Cs背景值所需的采样点数与采样面积

作  者：
刘志强;杨明义;刘普灵;田均良
单  位：
中国科学院教育部水土保持与生态环境研究中心
关键词：
137Cs背景值;网格采样;空间变异
摘  要：
137Cs背景值的确定是利用核示踪技术研究土壤侵蚀的前提和根本,直接关系到侵蚀速率计算的准确与否。而大部分研究对137Cs背景值的确定均采取随机采样,没有统一的采样点数与确定的采样面积。本研究利用网格加密采样法,对未扰动地和长期耕种且未平整的农耕地各两块样地的137Cs背景值空间变异进行了分析,结果表明:在未扰动地与农耕地采样地块,137Cs采样点数与背景值空间变异系数都存在指数回归关系;在未扰动地块137Cs背景值存在较大空间变异性,且随着网格面积的扩大137Cs空间变异系数表现为增加趋势,在0.25m2范围内选取最少11个样点才能满足试验精度;在农耕地采样地块,因长期的耕种作用使得137Cs在耕层中混合相对均匀,137Cs背景值空间变异性显著变小,最少选取7个样点就能满足试验精度,且不受采样面积的影响。
译  名：
SAMPLING NUMBERS AND AREA FOR THE CONFIRMATION OF ~(137)Cs REFERENCE INVENTORY
作  者：
LIU Zhi-qiang1,2,3 YANG Ming-yi1,2 LIU Pu-ling1,2 TIAN Jun-liang1,2(1.Research Center of Soil and Water Conservation & Ecoe-nvironment,Ministry of Education,Chinese Academy of Sciences,Yangling,Shaanxi 712100;2.State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau,Institute of Soil and Water Conservation/Northwest Sci-Tech University of Agriculture and Forestry,Yangling,Shaanxi 712100;3.Graduate School,Chinese Academy of Sciences,Beijing 100049)
关键词：
137Cs reference inventory;grid sampling;spatial variability
摘  要：
Confirmation of the137Cs reference inventory is the premise and foundation of using137Cs technique to study soil erosion.However,most investigators made the137Cs reference inventory using haphazard approach and lacked the uniform sampling numbers and sampling area.The sampling method of gradually increased grid density was used to study the spatial variation of137Cs reference inventory on undisturbed land and cultivated land in this paper.The results indicated that137Cs inventory showed spatial variation greatly on the undisturbed area.The exponential regression appeared between the number of reference points and CV.With the increasing of grid area,the coefficient of variation of137Cs content displayed the increased trend.And to satisfy the required accuracy of experiment,at least 11 points should be sampled in the area of 0.25m2.However,due to long-term cultivation on crop land,the137Cs content was mixed uniformly within the plough layer,and the spatial variation decreased obviously.The sampling numbers of reference points had also the exponential regression relationship with CV.At least 7 points should be sampled to reach accuracy of experiment,and the sampling numbers were not affected by sampling area.

相似文章

导出引用
计量
文章访问数: 9
HTML全文浏览量: 0
PDF下载量: 0

所属期刊

推荐期刊

友情链接Friendly link
农业信息研究所Agricultural information institute 农业智能知识服务平台Agricultural intelligent knowledge service platform 农业学术服务平台Agricultural Knowledge Service System 中国知网CNKI 维普网VIP 万方WANFANG DATA
联系我们Contact us

电话Tell：010-82109652-808

邮箱E-mail：agrijournal@caas.cn

服务Service
关于我们About us 意见建议Opinions and suggest
版权说明Copyright
单位：中国农业科学院农业信息研究所 中国农学会 © 2017中国农业科学院农业信息研究所 ICP备案号：京ICP备09089781号-46