摘要
【目的】利用遥感信息技术和DNDC生态过程模型相结合对水稻田排放的温室气体通量进行模拟和定量估测,并分析其排放的时空动态格局【。方法】利用遥感技术对覆盖辽宁省大洼县的卫星图像(LandsatTM和CBRES2)进行土地利用/覆盖分类,提取研究区1988年和2005年的水稻田空间分布特征信息并计算其面积。应用DNDC模型对这两个时期进行温室气体(CO2、N2O、CH4)排放通量模拟,分析辽东湾沿海地区水稻田温室气体排放的时空动态。【结果】与1988年相比,2005年的水稻田的面积约增加7066.2公顷。1988年整个研究区CO2、N2O和CH4排放总量分别为-1.20TgC、2.57×10-4TgN和1.4×10-2TgC,而2005年为-0.72TgC、2.69×10-4TgN和1.7×10-2TgC。空间分布上表现为CO2在东、南部为高吸收,中北部低吸收的特征;N2O在中东部和西部地带排放低,北部排放高的特征;CH4在中东部和西南排放高,北部和东南部地带排放低。同时,净全球增温潜势具有在2005年比1988年空间差异小的特点。【结论】人口和经济因素是影响水稻田面积变化的主要原因。水稻田是一个重要的CO2汇,是N2O和CH4的排放源,并且排放通量的时空差异明显。
[Objective] Integration of remote sensing technique and DNDC model was applied to simulate and estimate quantitatively the flux of greenhouse gas emission from rice paddy field, and the temporal-spatial pattern of emission flux was analyzed in this study [Method] The Landsat TM and CBRES remote sensing images which were acquired in 1988 and 2005 were used for classifying the Land Use/Cover in Dawa county, Liaoning province. The purpose is to extract the temporal-spatial distribution of rice paddy field and compute its area. The DNDC model was driven to simulate the flux of gas （Carbon dioxide, nitrous oxide, methane） emission in two periods, and the spatial-temporal dynamics of greenhouse gas （GHG） emission from rice paddy field in Liaodong coastal region was analyzed. [Result] By comparing area of rice paddy field, there were more 7 066.2 hectares in 2005 than in 1988. The total emission of three GHG （CO2, N20 and CH4） were- 1.20Tg C, 2.57 ×10^-4Tg N, 1.4 ×10^-2Tg C in 1988, and -0.72Tg C, 2.69 ×10^-4Tg N, 1.7 ×10^-2Tg C in 2005, respectively. The spatial distribution of GHG flux rate showed that CO2 high absorb region was in the east and south of the studied area, low absorb region was in the mid-north, low N2O emission was in the mid-east and west, its high emission was in the north, high CH4 emission was in the mid-east and the southwest and low emission was in the north and the southeast, respectively. For the net global warming potential （GWP）, the spatial difference in 2005 were smaller than that in 1988. [ Conclusion ] Demographic and economic benefit are key factors of driving area change of rice paddy field. The rice paddy field is the sink of CO2, source of N2O and CH4. And the temporal-spatial difference of their emission flux is significant.
出处
《中国农业科学》
CAS
CSCD
北大核心
2007年第10期2250-2258,共9页
Scientia Agricultura Sinica
基金
国家重点基础研究发展规划(973)项目(2002CB410810)
辽宁省自然科学基金项目(20032080)
辽宁省科技攻关项目(2006301040)
关键词
温室气体
DNDC模型
水稻田
排放通量
遥感图像
Greenhouse gas
DNDC model
Rice paddy field
Flux of emission
Remote sensing images
作者简介
张远（1975-），男，辽宁台安人，讲师，博士研究生，研究方向为农，林业遥感应用与生态系统模拟研究。E-mail：zhangyuan75@163．com。
通讯作者 吴嘉平（1962-），男，浙江义乌人，教授，研究方向为地理空间过程定量与系统模拟模型。Tel：0571-86971813；E-mail：jw67@zju．edu．cn
