Changes of urban wetland landscape pattern and impacts of urbanization on wetland in Wuhan City

With the acceleration of the process of building a national-level central city in Wuhan, the landscape pattern of the city has undergone tremendous changes. In this paper, remote images are classified through the neural network classification method, based on texture extraction, and the evolution of landscape patterns was quantitatively analyzed, based on the method of moving windows, landscape metrics and urban density calculation, in order to accurately extract landscape types and perform quantitative analyses. Wuhan City is taken as an example. The surface coverage of Wuhan City from 1989 to 2016 is divided into four types: agricultural landscape clusters, forest landscape clusters, water landscape clusters, and urban landscape clusters. It was concluded that, during the study period, the landscape heterogeneity of the entire area in Wuhan has increased, but the central urban area in Wuhan has decreased. The development of urban areas has compacted inwards but expanded outwards. In addition, the western part of Wuhan City developed better than the eastern part.

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CHANGES IN LANDSCAPE PATTERN OF WETLAND AROUND HANGZHOU BAY

ISPRS Annals of Photogrammetry Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-annals-iv-3-153-2018 ◽

2018 ◽

Vol IV-3 ◽

pp. 153-159

Author(s):

Wenpeng Lin ◽

Yuan Li ◽

Dan Xu ◽

Ying Zeng

Keyword(s):

Landscape Pattern ◽

Coastal Wetlands ◽

Coastal Wetland ◽

Diversity Index ◽

Scientific Basis ◽

Paddy Fields ◽

Hangzhou Bay ◽

The Sustainable Development ◽

Wetland Landscape ◽

Ecological Resources

Hangzhou Bay is an important estuarial coastal wetland, which offers a large number of land and ecological resources. It plays a significant role in the sustainable development of resources, environment and economy. In this paper, based on the remote sensing images in 1996, 2005 and 2013, we extracted the coastal wetland data and analyzed the wetland landscape pattern of the Hangzhou Bay in the past 20 years. The results show that: (1) the area of coastal wetland is heading downwards in the recent decades. Paddy field and the coastal wetland diminish greatly. (2) the single dynamic degree of wetland of the Hangzhou Bay displays that paddy fields and coastal wetlands are shrinking, but lakes, reservoirs and ponds are constantly expanding. (3) the wetland landscape pattern index shows that total patch area of the coastal wetland and paddy fields have gradually diminished. The Shannon diversity index, the Shannon evenness index as well as the landscape separation index of the coastal wetlands in the Hangzhou Bay increase steadily. The landscape pattern in the study area has shown a trend of high fragmentation, dominance decreases, but some dominant landscape still exist in this region. (4) Urbanization and natural factors lead to the reduction of wetland area. Besides the pressure of population is a major threat to the wetland. The study will provide scientific basis for long-term planning for this region.

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