荆州市农田植被净初级生产力时空特征分析

Space-Time Characteristics of Net Primary Productivity of Farmland Vegetation in Jingzhou City

基于MODIS数据和光能利用率模型估算的植被净初级生产力(NPP)数据,辅以气候和土地利用数据,利用趋势分析、GIS分析和统计分析方法,探讨了2000—2015年荆州农田NPP的时空特征。结果表明:1)2000—2015年荆州农田年NPP均值略有下降趋势,但整体上趋于平稳。年NPP总量呈增加趋势,2000—2005年呈增加趋势,2005—2009年呈波动性下降趋势,2009—2016年呈增加趋势。2)空间分布上,2000—2015年荆州市农田NPP存在时空异质性,NPP年均最大值为江陵县,最低的地区是沙市区和洪湖市。3)荆州农田NPP有64.32%为无显著变化,显著上升和显著下降区域分别为3.82%和31.86%。农田NPP呈显著上升的区域主要分布在江陵县、沙市区、监利县以及零星分布在洪湖市和松滋市,农田NPP呈显著下降的区域主要分布在荆州市西南部的松滋市、公安县和石首市,东北部的洪湖市,以及西北部的荆州区。

Based on MODIS data and light energy utilization rate model to estimate NPP data,supplemented by climate and land use data,by using the trend analysis,GIS analysis and statistical analysis method,we here discusses the space-time characteristics of vegetation net primary productivity of farmland in Jingzhou City for 2000-2015.The results show that:(1)the annual average NPP of farmland in Jingzhou decreased slightly,but the overall trend was stable during the period from 2000 to 2015.The total amount of NPP increased in 2000-2005,the volatility decreased in 2005-2009 while increased in 2009-2016;(2)in terms of spatial distribution,there are spatial and temporal heterogeneity in farmland NPP of Jingzhou city for 2000-2015.The annual maximum NPP was in Jiangling County,while the lowest area was in Shashi District and Honghu City;(3)there was no significant change in the NPP being about 64.32%of the Jingzhou farmland,while the areas with significant rise and fall were of 3.82%and 31.86%of the farmland,respectively.The areas with significant increase of farmland NPP are mainly distributed in Jiangling County,Shashi district,Jianli County and scattered in Honghu City and Songzi City.The areas with significant decrease of farmland NPP are mainly distributed in in Songzi City,public security county and Shishou City,the southwest of the Jingzhou City,Honghu City;in the northeast,named as Honghu City and in the northwest,i.e.Jingzhou District.