Dynamic Monitoring Of Napahai Wetland In Northwest Yunnan Based On GIS, RS & GNSS Technologies

Napahai is a seasonal wetland of the Jinsha River Basin in Northwest Yunnan, which is located in low latitude and high altitude plateau. Be different from wetlands in Northern China and Ruoergai wetland, Napahai wetland has distinctive characteristics, which was developed in limestones. Because strongly affected by the karst, Napahai wetland’s ecosystem was relatively fragile, and it was unique type of Chinese wetlands. Napahai wetlands can regulate snow melt water, surface runoff and river water, control the erosion of soil, and plays an important role on the Yangtze River water levels and water balance. With the development of economic and global temperature changes, the wetland classes of Napahai wetland ecosystems had a great transformation occurred. Therefore, in order to achieve the goal that the sustainable development of wetland protection and ecological in Napahai, it is necessary to monitor the trends for the realization of Napahai plateau wetland.In this paper, the ETM+ images of 2000, 2007 and OLI image of 2014 were used as the master data source, while administrative maps, topographic maps, weather data, historical statistics bulletins and field survey data were assists. Supported by 3S technologies, i.e. Remote Sensing(RS), Geographic Information Systems(GIS) and Global Navigation Satellite System(GNSS) technologies, this paper used human-computer interaction interpretation to extract information, and used landscape pattern analysis and data comparison methods to research the changes for the past 14 years of Napahai wetland. This paper had analyzed driving forces of wetland class changes from natural factors and human activities in terms, and had proposed protection and rational utilization measures of Napahai wetland. The main results are as follows:(1) Process remote sensing images and establish wetland classification system. To process the images such as geometric correction, band combination, image fusion, cutting and other pretreatment, get the remote sensing images of 2000, 2007 and 2014 in the study area. On the basis of the plateau wetland classification system, combined with the characteristics of the study area of natural environment, this paper established a classification system of Napahai wetland.(2) Wetland remote sensing information extraction and spot survey correction. By comprehensive analyzing the features ETM +and OLI images, respectively establish interpretation signs of three images. Using ERDAS and ArcGIS software to human-computer interactive interpretation, got wetlands classification results of three images, including farmland, lake, swamp, meadow and construction land. Through field investigate to verify the classification accuracy, and correct the incorrect parts, so that the extracted information is more accurate.(3) Wetland landscape pattern analysis. The use of GIS spatial analysis and Excel’s statistical functions, in terms of the number of patches, patch area, landscape proportion, patch density index, landscape diversity index and fragmentation index to analyze the landscape pattern of Napahai wetland; from wetlands Class quantity to analyze conversion of Napa wetland from 2000 to 2014. The results showed that: Napahai wetland to lake, swamp and meadow in the main, and the conversion among these were the most active.(4) Simulation of CA-Markov without policy intervention in the case on 2014 in Napahai wetland. Compared the real value with the forest we knew that under the intervention of the normal development of the policy, various types of Napahai Wetland, artificial wetland, water wetland, river wetland and marsh wetland are the output types, leading to atrophy of the lake, marsh meadow; while meadow and the construc tion land are the input types.(5) The driving forces analysis of wetlands classes changed, wetlands optimal utilization and protection of Napahai wetlands. This article mainly analyzed the wetland class changes from the natural factors and human activities, including hydrology, rainfall, temperature, urban and rural construction, overgrazing and tourism. In order to ensure the coordination and sustainable development of the natural environment and the economy, this paper proposed that we should strengthen the management of nature reserves, moderate grazing, promote the development of eco-tourism and legislation and law to protect wetlands and other recommendations.