成都郫县土壤氮素养分在城市化进程中的时空变异特征

利用抽样调查法和地统计学方法,在ArcGIS8.1地理信息系统平台上,对地处成都西郊的郫县耕层土壤1981年93个样点和2002年46个样点氮素含量的时空变异特征进行了研究。结果表明,2002年该县土壤全氮和碱解氮含量平均为1.61g/kg和159mg/kg,分别比1981年下降了8.45%和增加了16.99%。21年间由于受城市化进程的影响,全氮区域变化幅度呈由东向西逐渐减小的趋势;而碱解氮含量同时受施肥水平的影响,区域变化幅度为西部高于东部和中部;并且该县不同水稻土的全氮含量和碱解氮含量变化状况也不尽相同。

Temporal and Spatial Variability of Soil Nitrogen in Urbanization Process in Pixian, Chengdu

The temporal and spatial variabilities of soil total nitrogen (STN) and available nitrogen (SAN) were studied by comparing their changes in the arable layer in Pixian county, the suburb of Chengdu in 1981 and 2002. 46 sampling points of 2002 and 93 sampling points of 1981 were selected. The temporal and spatial variabilities of STN and SAN were expressed by spherical semi-variance model and the ordinary kriging interpolated method. The results indicate that the average contents of STN and SAN in the county are 1.61?g/kg and 159?mg/kg in 2002, decreases by 8.45% and increases by 16.99% in contrast with those in 1981, respectively. In Pixian county, because of the urbanization, the variable range of STN in the east is higher than that in the central and the west, and the variable range of SAN in the west is higher than that in the central and the east. At the same time, the variable range of STN and SAN are not the same in different paddy soils.