The Yellow River Delta Wetland Information Extraction And Dynamic Change Analysis Based On Landsat Data

Wetland resources are precious natural resources in China.With the development of society,great changes have taken place in the wetland environment of our country.The change of the wetlands in the Yellow River Delta is one of the epitomes.To gain a deeper understanding of the temporal and spatial distribution and dynamic changes of the Yellow River Delta wetlands in the past 30 years.Six periods(1986,1992,1998,2004,2010 and 2016)of Landsat satellite data were selected to analyze the spatial and temporal distribution and dynamic changes of the Yellow River Delta Wetland between 1986 and 2016.Additionally,the selected methods such as spectral indices Modified Normalized Difference Water Index(MNDWI)and Normalized Difference Vegetation Index(NDVI),principal component analysis(PCA)and visual interpretation were combined to build the hierarchical classification approach to extract the land cover and wetland classification information.Based on the theoretical analysis of geography information TUPU to analyze the dynamic changes of land cover and wetlands in the research area in the past 30 years.Use the CA-Markov model to predict the land cover types in the study area in 2022.The results showed that:1.Hierarchical classification discrimination method can eliminate the interference of the determined category and improve the classification accuracy.The proposed hierarchical classification method has good classification accuracy.Using the hierarchical classification method,the overall accuracy of land cover and wetland classification in the six periods is higher than 85.00%.The overall classification accuracy of the data in 2010 reached 94.90%,which is suitable for information extraction in the Yellow River Delta region;2.In the study area,between 1986 and 2016,the distribution and area of land cover and wetland had changed greatly,and the serious degradation occurred to natural wetland.The area of mud flat decreased by 741.84 km~2,of which 237.06 km~2 was converted into aquaculture and114.79 km2 into salt pan.The area of swamp wetland reduced by 299.47 km2,of which 221.66km~2 was converted to the farmland.The area of the river has not changed much.Meanwhile,the area of artificial wetlands,such as salt pans,aquaculture and reservoir increased by 225.11 km~2,402.71km2 and 423.51km2 respectively,shows a significant increase trend.The total area of natural and artificial wetlands does not change much.3.Combined with Dongying City Yearbook data,the land cover types and wetland changes in the study area are greatly affected by human activities.The large-scale expansion of artificial wetlands such as aquaculture and salt pans has caused severe damage to local natural wetlands.It is necessary to balance the development of human society Demand and wetland protection.The CA-Markov model predicts that the wetland information of the Yellow River Delta in 2022showed that the aquaculture and salt pans in Dongying City will further expand in 2022.The future wetland protection work needs to reasonably plan the scale of artificial wetlands construction and pollution prevention and control.