Research On Landscape Change Of The Yellow River Delta During The Last 32 Years

The Yellow River Delta is the youngest area with the most sharply changing in this country, and there is also the most perfect wetland system of temperate regions. Its evolution process of land use/land coverage is always hot spot. Under the effect of two national strategies, named ‘Yellow and Blue’, its land use and landscape pattern change is remarkable. This research, based on a number of remote sensing images, comparing with the newest image of Landsat 8 OLI in 2014, through several space analyzing and data processing technologies of GIS, combining relevant statistical index, is on analyzing the land use and land coverage change qualitatively, relevant dynamic index, transfer matrix and landscape pattern index quantitatively of the Yellow River Delta from 1983 to 2014.The research analyzed the land use evolution and landscape pattern change and the following ecological effects. The results as:⑴Land use types distributions and changes during the 32 yearsArea increase of the Yellow River Delta occurred in estuary regions mostly, and its main power is from sediment depositing; The laws of land use type changes are following: the area of city/neighborhood/building and saltern /aquaculture increased dramatically, and many small size plaques appeared in forest to deepen broken degree much. The area of mud flat reduced clearly year after year and the wetland and farmland are broken. The land use type of the Yellow River Delta connected with different factors in Dong Ying City closely.⑵Analysis of land use of the Yellow River DeltaUse dynamic models to quantitatively describe range and speed of land use change, and the data showed: wetland and mud flat were disappearing from 1983 to 2014, and other land use types were increasing, especially area of city/neighborhood/building and saltern, which increased fastest from 1983 to 1995; Besides, this period was also the best increasing time of city/neighborhood/building and saltern /aquaculture, which is combined with urbanization and living levels closely in the same time; In this period, woodland was missing but not obviously; from 1995 to 2004, area of saltern /aquaculture and woodland increase a lot and city/neighborhood/building following, and mud flat and farmland had small changes. From 2004 to 2014, K value of woodland was the highest as 20.17 percent; the area of saltern /aquaculture and city/neighborhood/building was really increasing much more slowly,and the K value were 7.02 and 3.56 percent; in this time, mud flat was missing quickly as its K value-4.88 percent. Its changing speed was much higher than average levels of last years.⑶Analysis of transfer matrix of land use types of the Yellow River DeltaFrom 1983 to 2014, 1983 to 1995, 1995 to 2004, 2004 to 2014, the transfer matrix of land use type changes was analyzed to show these: wetland had the biggest contribution and most were transferred to farmland, saltern /aquaculture and city/neighborhood/building as 64.16 percent, half of which are transferred to farmland; these three are occupied all the area transferred out 95.33 percent; contribution of transferring in of farmland was the biggest, which were most from wetland and woodland following; in this whole researching period, area of saltern /aquaculture increased most observably, city/neighborhood/building following and farmland as the third.⑷Analysis of driving force of land use of the Yellow River DeltaThese natural factors, such as geographic location, terrain and landscape, hydrology conditions and climate change, as prerequisites influencing land use structure of researched region, decided the main vegetation conditions; these human factors, such as population change, policy guide, economy development and technology levels of land use, were the dominant factors of land use structure change, and was also controllable factors to perfect area land use structure.⑸Analysis of landscape ecology effect change in the 32 years, divided to 8 agesLandscape piece type area index, average plaque area index, plaque number, SHDI, SHEI, and ED were statically analyzed to present: as the basic constitution, farmland and wetland were the main land use types in the Yellow River Delta; human activities leaded to the obviously plaques number increasing and average plaques area changing, which also leaded to a lot of small size plaques coming out, and the broken level of landscape increased a lot; overdevelopment made wetland and mud flat disappearing, who offered living room to the creatures, and made plaque size smaller, which threatened creatures’ minimum living room, lost biodiversity; landscape diversity index continued to rise and landscape heterogeneity was improving; ED was increasing sharply, and edge effect of area was obvious, and safe core area was missing; all these above affected much on stability of living environment.