机构地区:[1]江西师范大学地理与环境学院,江西南昌330022 [2]江西省寄生虫病防治研究所
出 处:《中国病原生物学杂志》2018年第10期1113-1120,共8页Journal of Pathogen Biology
基 金:国家自然科学基金项目(No.41361104;81660557);江西省重点研发计划(No.20171BBG70105);江西省重大生态安全问题监控协同创新中心项目(No.JXS-EW-00)
摘 要:目的研究近年来受长期低枯水位影响下的鄱阳湖国家级自然保护区钉螺孳生地时空分布。方法基于2015年10月-12月查获的螺情数据,结合2015年10月11日Landsat8OLI遥感影像反演的归一化植被指数(NDVI)和鄱阳湖湖区湖底地形(DEM),应用相关性分析法研究鄱阳湖湖区螺情与NDVI和DEM之间的关系;根据活螺平均密度在NDVI和DEM的分布规律,获得出钉螺孳生地分布的NDVI和DEM阈值范围,利用面向对象的分类法对研究区内8个时相的Sentinel-2A光学遥感影像进行钉螺孳生地提取并分析其特征。结果鄱阳湖湖区2015年秋季活螺平均密度与NDVI呈正相关性(r=0.665,P<0.01),与DEM呈负相关性为(r=-0.620,P<0.01);有螺框出现率与NDVI呈正相关性(r=0.742,P<0.01),与DEM呈负相关性(r=-0.632,P<0.01)。钉螺密度随着植被指数(NDVI)的增大而上升,8.5~11m高程为钉螺孳生的扩张区域。结论鄱阳湖湖区洲滩植被与钉螺孳生区呈现向洲滩低高程区域缓慢扩张的趋势,8.5~11m高程为钉螺孳生的扩张区域。鄱阳湖国家级自然保护区钉螺孳生地时空变化与同时期星子站水位显著相关,星子站水位越低洲滩出露越多,钉螺孳生区范围月大。Objective To study the spatial and temporal distribution of snails in the Poyang Lake National Nature Reserve as a result of low water levels over the past few years. Methods Snail data from October to December 2015 were combined with 2 environmental remote sensing indicators. The normalized vegetation index (NDVI) was derived from the inverse of remote sensing imagery from Landsat 80LI (October 15, 2015), and the topography of the bottom of Poyang Lake was determined to create a digital elevation model (DEM). Correlation analysis was used to statistically analyze the relationship between the two RS environmental indicators and the snail situation in Poyang Lake. According to both the NDVI and DEM, the mean density of living snails followed a normal distribution. This yielded the NDVI and DEM thresholds for the distribution of Oncomelania breeding grounds. Object-oriented classification was used to identify snail breeding grounds from Sentinel--2A remote sensing imagery of the study area in 8 phases. Results The mean density of living snails in the Poyang Lake area in the autumn of 2015 was significantly related to the NDVI and DEM. The correlation between the mean density of living snails and the NDVI was 0. 665 (P〈0.01), and the correlation between the mean density of living snails and the DEM was -0. 620 (P〈0.01). The correlation between the prevalence of frames with living snails and NDVI is 0. 742 (P〈0.01). and the correlation between the prevalence of frames with living snails [snails are sampled using a square frame] and the DEM was -0. 632 (P〈0.01). The density of Oncomelania snails in creased with an increase in the vegetation index (NDVI). Oneomelania breeding grounds expanded at an elevation of 8.5-11 m. Conclusion Waterline vegetation and Oncomelania breeding areas around Poyang Lake tended to gradually expand where the waterline was low. Oncomelania breeding grounds expanded at an elevation of 8.5-11 m. The spatial and temporal variation of Oncomelania snail ha
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...