水保所知识产出(1956---)知识库

华北平原作为我国的粮食主产区，土壤水分是制约作物生长的主要限制因子。本文首次运用土壤水分指数
数据，对华北平原土壤水分以及灌溉特征进行空间分析，旨在为区域尺度农田旱情以及农作物产量的实时监测与
预报提供相关参考。研究基于1993—2002 年华北平原逐旬降雨数据和主动微波遥感反演的土壤水分指数数据，
应用地统计分析方法，分析典型干旱年( 1999 年) 该区表层土壤水分时空变异特征，并提取和分析小麦生长期内的
灌溉信息; 通过对逐旬的降水和土壤水分数据的空间叠置分析，提取区域内的灌溉信息。结果表明: 1999 年降水量
比多年( 1993—2002 年) 平均量少约140 mm; 1999 年土壤水分变化与降水变化整体保持一致，低于多年平均水平，
春季和夏季，土壤水分减少尤为明显，土壤干旱非常普遍; 小麦生长期内，大部分地区均存在不同程度的灌溉，其中
中部地区灌溉次数最少，占研究区面积的65%左右的南部和北部地区灌溉次数多为2 ～ 3 旬次。采用降水量和遥
感水分监测数据，可以分析土壤水分变化的原因，提取灌溉的范围和时间特征，并可为旱情遥感监测提供科学
参考。

［Background］ Soil moisture is one of the most important components of soil，it plays a
critical role in the process of soil formation． Moreover，soil moisture is the main source of crop water，and
is one of the most crucial parameters for the agriculture，meteorology and hydrology studies． As the
important agricultural region in China，in addition to the precipitation recharge，soil moisture in the North
China Plain ( NCP) is also largely affected by irrigation． How to monitor and analyze surface soil
moisture，drought and irrigation of a wide range using remote sensing data，has a especially important
value． Studies on soil moisture and irrigation information can provide better understanding about thedrought． ［Methods］ On the basis of 10-day’s precipitation data，active microwave remote sensing
inversion data - soil moisture index ( SWI) data，combined with geo-statistical analysis methods，the
spatial and temporal variation of surface soil moisture under precipitation drought in the NCP was analyzed
and irrigation information in the main growing season of winter wheat was extracted by the method of
spatial overlay analysis． ［Ｒesults］1) There were some differences in the amount and distribution of
precipitation between 1999 and 1993-2002． Precipitation in June，July and August of 1999 was 50 mm
lower than the average of 10 years ( 1993-2002) ，precipitation in September and October of 1999 was a
little higher than the average of 10 years ( 1993-2002) ; precipitation in 1999 was more evenly distributed
than annual average of 1993-2002． Precipitation in the NCP in 1999 was 140 mm less than the average of
10 years ( 1993-2002) ． 2) The change of soil moisture was consistent with the change of precipitation，
which had regular fluctuation． The SWI in 1999 was lower than the average of 10 years ( 1993-2002) ，
especially from March to September，which was consistent with variation of precipitation; the SWI
decreased remarkably in spring and summer，which caused the soil drought to some extent． The
differences of SWI between 1999 and 1993-2002 were different in different regions; the differences of soil
moisture content in different stages was significant in the same area． 3) Most areas in the NCP in 1999
were irrigated in different degrees in the main growing season of winter wheat; the irrigation times in the
middle part was the least，and there existed two or three rounds of irrigation in the northern and southern
parts，which accounted approximately 65% of the total study area． The irrigation cells were 79. 69%
same with extracted result using land use data in 2000． ［Conclusions］The decrease of precipitation in
1999 had an effect on variation of SWI． The soil moisture in 1999 decreased，which was consistent with
the change of precipitation，indicating the arid characteristic of soil． There existed different degrees of
irrigation in the NCP in 1999． The study results and methods may provide references for the agricultural
drought monitoring based on remote sensing．