论文部分内容阅读
量化土壤时空变化对生态系统模型、精准农业和自然资源管理有重要意义。为了更好地控制环境问题,本文把传统统计方法、地统计学方法和地理信息系统三者结合起来,研究了中国西北部额济纳旗(1480 km~2)不同植被覆盖类型土壤氮的时空变化。于2011年与2015年从49个样点采集了98个0~15 cm土壤样品,测量了土壤全氮和硝态氮的含量,比较了不同植被覆盖类型土壤全氮和硝态氮的空间变化和时间变化。结果表明:土壤全氮含量明显受植被覆盖类型影响;土壤全氮平均值变幅为0.259~0.904 g kg~(-1),胡杨林地土壤全氮含量>柽柳地土壤全氮含量>梭梭地土壤全氮含量;2011年与2015年同一植被覆盖类型下土壤全氮含量差异不显著;2011年胡杨林地、柽柳地、梭梭地土壤硝态氮含量分别为45.185 mg kg~(-1)、76.95mg kg~(-1)、39.335 mg kg~(-1),2015年胡杨林地、柽柳地、梭梭地土壤硝态氮含量分别为2.259 mg kg~(-1)、21.546 mg kg~(-1)、14.554 mg kg~(-1);胡杨林地和柽柳地土壤全氮呈中等强度空间相关性,梭梭地土壤全氮呈强空间相关性;植被覆盖类型明显影响着植被中氮的转移、转化和吸收;研究区土壤氮素含量呈现剧烈的时空变化。
Quantifying temporal and spatial changes of soil is of great significance to ecosystem modeling, precision agriculture and natural resource management. In order to better control the environmental problems, this paper combines the traditional statistical methods, geostatistics methods and geographic information systems to study the spatio-temporal variations of soil nitrogen in different vegetation cover types in Ejin Banner (1480 km ~ 2) in Northwest China. 98 soil samples 0 cm to 15 cm were collected from 49 sampling sites in 2011 and 2015. The contents of soil total nitrogen and nitrate nitrogen were measured. The spatial variability of soil total nitrogen and nitrate nitrogen was compared between different vegetation cover types And time changes. The results showed that soil total nitrogen content was significantly affected by the vegetation cover types. The mean value of soil total nitrogen varied from 0.259 to 0.904 g kg -1, the total nitrogen content in Populus euphratica forest> the total nitrogen content in Tamarix sargus> The content of soil total nitrogen was not significantly different in the same vegetation cover types between 2011 and 2015. The contents of nitrate nitrogen in Populus euphratica, Tamarix and Haloxylon were 45.185 mg kg -1 in 2011, 76.95 mg kg -1 and 39.335 mg kg -1 respectively. The content of NO 3 -N in soil of Populus euphratica, Tamarix sargassum and Haloxylon ammodendron was 2.259 mg kg -1 and 21.546 mg kg -1 in 2015, -1) and 14.554 mg kg -1, respectively. The soil total nitrogen in Populus euphratica forest and Tamarixche deserticola showed medium-intensity spatial correlation, and the total nitrogen in Haloxylon ammodendron soil had a strong spatial correlation. The vegetation coverage type significantly affected the nitrogen Transfer, transformation and absorption of soil nitrogen content in the study area showed dramatic temporal and spatial changes.