华阳河湖群地区滩涂地动态遥感监测研究

Study on Tidal Flat of Huayang Rivers and Lakes District Based on Remote Sensing Dynamic Monitoring

本文首先对华阳河湖群地区1990年、2002年、2010年TM,ETM+数据进行分类,基于GIS软件对近20a滩涂地时空变化、转移过程及典型样带质心转移进行了分析,并应用马尔科夫链预测了未来土地利用变化,为本区滩涂地保护和利用及渔业发展提供一定的科学依据。结果如下:(1)滩涂地总面积减少。1990—2002年减少了4.44km2,2002—2010年减少了10.31km2。(2)以农业生产为主的复兴镇、洲头乡由于滩涂围垦导致滩涂地向耕地转移,面积减少;作为水产养殖大镇的下仓因围网养殖和围湖造田使得湖泊转换为滩涂地,滩涂地面积增加。(3)下仓样带滩涂地质心呈集中趋势,距离缩小;汇口样带呈分散趋势,距离增大。(4)马尔科夫链预测显示,滩涂地、湖泊在未来依然呈减少趋势,耕地、建设用地会持续增加,而其他地类相对稳定。

Based on remote sensing and geography information system, and TM and ETM＋ data of the year 1990,2002 and 2010 in the region of Huayang rivers and lakes district were used. We got seven land use types including cultivated land, forest land, grassland, reservoirs and ponds, buildings, lakes and tidal flat, through the method of maximum likelihood. On the view of time and space, the dynamic changes of tidal flat, change ratio and transfer matrix of land use were analyzed. The centroids of tidal flat were analyzed by setting up two patterns along the lakeshore. In the end, following the Markov chain model, future tendency of the land use was predicted, and the results were satisfactory. The results were as follows： first, during 1990--2002, the tidal flat area decreased by 4.44 km^2 （from 15.67 km^2 in 1 990 to 41.23 km2 in 2002） ; dur- ing 2002--2010, it decreased by 10.31 km2 （from 41.32 km2 in 2002 to 30.92 km2）. The decrease rate during 2002--2010 was faster than that during 1990--2002. The areas of cultivated land, forest land and buildings increased, the increased areas were 96.03 km^2 , 10.03 km^2 , 4.32 km^2 , respectively. The areas of grassland, lakes and reservoirs decreased, the decreased areas were 1.91 km^2, 82.46 km^2, 11.26 km^2, respectively; second, the tidal flat decreased obviously in Fuxing and Zhoutou villages. The chief reason for that is the in- come mainly comes from farming in these villages, such as significantly inning and reclamation during recent 2 decades. However, the tidal flat in Xiacang village increased because Xiacang is one of the biggest villages with abundant fishery resources, cultivation and reclaim land from lakes lead to lakes dwindling and tidal flats increase gradually; and the major trends of the land utilization in this region are that lakes turned into tidal flat while tidal flat turned into cultivated land; third, by setting up patterns outside one kilometer of lakeshore in Xiacang village and Huikou village, the Changes of the centroid of tidal flat were analyzed, in the Xiacang pattern, the result showed that the centroids of tidal flat in different years obviously centralized and the distance reduced during the study period. It indicated that in this pattern, human activities as lake reclamation were centralized in the east shoreline of Huanghu. At the same time, in the Huikou pattern, the centroids of tidal flat were separated and the distance increased. It＇s separated because the exploitation and utilization of tidal flat were separated;last, Markov chain pvediction result showed that the areas of tidal flat and lakes would still decrease in the future, and the areas of cultivated and buildings would increase, while others areas of land types would keep stable. This study can provide scientific basis for the tidal flat protec- tion and rational utilization, and also play an important role in development of fishery in the region of Huay- ang rivers and lakes area.