摘要
对一块面积为１ ｈｍ ２ 麦田内的９８ 个观测点取样分析，测定了代表不同土壤含水率水平下的两个时期土壤表层和底层的 Ｎ Ｈ４ Ｎ、 Ｎ Ｏ３ Ｎ、 Ｏｌｓｅｎ Ｐ、表层有机质和全氮等养分。应用地统计学的方法对所取的数据进行了分析，结果表明底层土壤的 Ｎ Ｈ４ Ｎ、表层土壤的有机质服从正态分布；其余养分基本上服从对数正态分布；按一定的精度和置信水平确定了合理的取样数目。通过半方差函数分析，发现这些养分在一定范围内存在空间相关性；采用 Ｋｒｉｇｉｎｇ 方法对未测点进行了估值，绘制了等值线图，并对两个时期的养分动态的空间变异进行了初步分析。该成果可用于提高氮肥利用率和精确农业（施肥）的研究和实践。
Ninety eight observing points by a square of 10 m×10 m were made in a wheat field approximate 1 hm 2. Soil samplers were obtained from each point under two layers of 0~ 20 cm and 80~100 cm with different soil moisture and different time. Ammonia、NO 3 N、Olsen P in the soils of 0~20 cm and 80~100 cm, organic matter and total N in surface soil (0~20 cm) were measured. The geostatistics theory was applied to analyze the data, the results indicated that both NH 4 N in bottom soil and organic matter in surface soil showed a normal distribution, others with a lognormal distribution. The rational sample number was determined within a given precision at a known confidence level. Semivariance analysis gave that those nutrients were correlated in a given spatial range. The Kriging method was applied to calculate the unobserved points and generate the contour map. Preliminary analysis was made for the spatial dynamic variability of those nutrients in different time. These results shows some merit in increasing nitrogen use efficient and precision agriculture.
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
1999年第3期33-38,共6页
Transactions of the Chinese Society of Agricultural Engineering
基金
中澳合作ACIAR项目(LWR1/96/164)
农业部"九五"科技攻关课题
关键词
土壤养分
空间变异
半方差函数
农田
soil nutrient
spatial variability
geostatistics
semivariance
