2011年洪湖和梁子湖受旱程度差异和成因分析

湿地是水陆交错的生态系统,往往受旱灾影响大,故此,对不同湖泊湿地受旱程度差异及其原因分析,可为减灾和湿地保护提供科学依据。本文利用2010年5月和2011年5月2个时相的HJ-1卫星CCD影像,提取洪湖和梁子湖2个时相的湿地水面积,结合统计资料和问卷调查数据,从湿地水面积及空间分布变化、湿地生态系统功能退化、湿地生态系统,对人类福祉影响3方面,分析了两湖湿地受旱程度的差异。并综合气象数据、统计资料和问卷调查数据,从气象因子、区域自然地理环境、湿地类型及特点、区域水文条件和湿地受保护程度5方面探讨两湖受旱程度差异的原因。结果表明：（1）2011年春旱期间,洪湖比梁子湖受旱程度更严重。旱灾时,洪湖水面积减少83.93 km2,减小比例为26%,梁子湖水面积减少13.02 km2,减小比例为4%;两湖的涵养水源、保护生物多样性、物质生产和水质净化功能均受到损害,洪湖较梁子湖更严重;受旱灾影响,洪湖湿地对人类福祉的消极影响大于梁子湖。（2）降雨量、气温和风速等气象因素、湖泊湿地成因类型、区域自然地理环境和水文条件是影响两湖受旱程度差异的主要因素,另外,湿地保护措施的差异及效果也会造成两湖受旱程度不同。

Analysis of the Difference and Genetic in Drought Degree of Honghu Lake and Liangzi Lake in 2011

Wetlands are ecosystems interlaced between water and land that are highly affected by drought. Analysis of the differing degree of drought from different wetlands can provide scientific bases for disaster mitigation and wetland conservation. Based on HJ-CCD images in two periods（May 2010 and May 2011）, we extracted the wetland water areas of Honghu Lake and Liangzi Lake, and then combining with statistical and questionnaire data we analyzed the differences of drought degree between the two lakes from three aspects：（1） the wetland water area change and its spatial distribution;（2） wetland ecosystem functional degeneration and（3） the influences of wetland ecosystem to human well-being. Subsequently, the differences of drought degree between the two lakes were analyzed from meteorological factors, wetland forming reasons and wetland types, regional geographical environment, regional hydrological condition and the wetland conservation degree. The three main meteorological factors, i.e. monthly average precipitation, temperature and wind speed, were selected because precipitation mainly affects the inflow of the lakes, while temperature and wind speed are the main factors in outflow of the lakes. Moreover, we also used the questionnaire data to analyze the differences of the wetland conservation measures and the understanding of local people to wetland protection. The results show that, the drought degree of Honghu Lake is more serious than Liangzi Lake. During the drought, water area of Honghu Lake has reduced83.93 km^2, with the proportion of 26%, while the water area reduction of Liangzi Lake is 13.02 km^2 with the proportion of only 4%. Many functions of the two lakes are damaged such as water conservation, biological diversity conservation, material production and water purification function. Since the damage degree of these functions of Honghu Lake is more serious than Liangzi Lake, Honghu Lake brings more negative impacts on human wellbeing than Liangzi Lake. The results also indicate that the