三江平原近50年耕地面积动态变化序列重建

基于1950-2000年三江平原23个县市和3个农垦管理局耕地面积的统计数据,利用空间插值和线性时间内插方法对统计缺失数据进行插补,重建其50年耕地面积时空变化序列。重建的耕地面积变化序列显示,1950年该区域耕地面积仅有88.7万hm2,到2000年增至269.6万hm2,增加了203.9%,除20世纪60年代后期外,该区域耕地基本表现为持续增加。在空间变化方面,近50年三江平原耕地面积增加的重心表现为由早期的平原西部逐渐向中东部转移。耕地面积变化的主要原因在于该区域3个农垦管理局所辖的农场对自然湿地的大规模垦殖,其108.8万hm2的耕地面积几乎全部源于近50年的湿地垦殖。

Building up Annual Series of Cropland Acreage in Sanjiang Plain in the Last 50 Years

Wetland has been persistently reclaimed in Sanjiang Plain from 1950 to 2000,and nearly all of the reclaimed wetland was converted into cropland.With the agricultural statistic data of 23 counties and the three farm administrative agencies in Sanjiang Plain from 1950 to 2000,temporal and spatial changes of cropland acreage in Sanjiang Plain were figured out.In 1950 there were 0.887 million hm2 cropland and after 50 years it increased to 2.696 million hm2,the increment was about 203.9%.Spatial analysis showed that in the early stage the wetland reclamation was conducted in the west part of the plain and moved eastward thereafter.The three farm administrative agencies were the main contributors to the wetland reclamation in Sanjiang Plain.Most of the farms were founded in 1950s,and to the year 2000 they had 1.088 million hm2 cropland.