摘要
以鄱阳湖流域土地利用数据为基础,定量分析2005年以来鄱阳湖流域土地利用变化特征;借助空间自相关、地统计分析等方法,揭示了鄱阳湖流域土地利用变化下生态风险时空演变特征。结果表明:2005—2013年,鄱阳湖流域土地利用转移非农化趋势明显;土地利用生态风险呈小幅上升趋势,在空间分布上具有显著相关性,生态风险"北热南冷"空间分异及等级扩散特征明显;依据空间差值结果可将研究区划分为低生态风险区(ERI<0.15)、较低生态风险区(0.15≤ERI<0.25)、中等生态风险区(0.25≤ERI<0.35)、较高生态风险区(0.35≤ERI<0.45)、高生态风险区(ERI≥0.45)5类;高风险区域主要分布在滨湖区、南昌、九江及赣中部分地区。生态风险等级分布与地形存在显著相关性,随着生态风险等级提高,分布区域表现出明显的地形指向性。以土地利用结构对生态风险进行表征,尝试从宏观上把握大尺度区域生态安全格局,为鄱阳湖流域土地利用格局优化提供了相关借鉴及建议。
The ecological impact of different land use types and intensity could reveal on regional ecosystem structure changes directly, and the changes of structure and function of land ecosystem would profoundly affect regional ecosystem health. Therefore, ecological risk assessment in terms of landscape structure is an effective method to study regional ecological risk pattern. Poyang Lake, the largest freshwater lake in China, plays an essential role in biodiversity protection and water ecological security in Yangtze River basin. However, irrational development and construction activities have resulted in significant landscape changes in recent years, which may aggravate regional ecological risk. This study takes Poyang Lake basin as a case study to explore the impact assessment model derived from land use structure, the of land use change on ecological risk. Based on an ecological risk study tries to explore ecological security pattern and provide a scientific reference for optimizing land utilization in Poyang Lake basin. The characteristics of land use changes in Poyang Lake watershed were analyzed quantitatively based on land variation of the ecological risk and the relationship between use data during 2005--2013. Then, the spatial-temporal ecological risk and terrain factors were investigated by GIS techniques. The result shows that about 9.2% of the total areas experienced land use changes, which 68.5% occurred among farmland, construction land and forests. The major types of land transformation are mutual conversion between forests and farmland, and the conversion of farmland to construction land, showing a remarkable trend of non-agricultural transformation. The average ecological risk index （ERI） increased from 0.237 in 2005 to 0.246 in 2013, probably as the consequence of farmland reduction and rapid expansion of construction land. The ERI showed a positive spatial autocorrelation and obvious local spatial clustering, and generally decreased significantly from north to south. Based on the spatial interpol
出处
《生态学报》
CAS
CSCD
北大核心
2016年第23期7850-7857,共8页
Acta Ecologica Sinica
基金
国家自然科学基金资助项目(41561025)
江西省重大生态安全问题监控协同创新中心资助项目(JXS-EW-00)
