Relationship between Land Use Pattern and Water Security of Drinking Water Conservation Areas in Guangzhou

Water conservation and drinking water safty are the prerequisite and basis for urban development.Both delimitation of dringking water conservation areas and rationalization of people ' s mode of life and production are important measures to guarantee regional water quality and drinking water security.Based on TM images,historical environmental data for water quality,and 3S technology,a preliminary study is performed to discuss land use quantity and spatial allocation of water conservation area and its relationship with dringking water safly.This can help us understand the importance of conserving ecological elements around water sources.The main conclusions we reached are:1) Nowadays,with rapid urban expansion,water security should be ensured by a new appropriate conservation area,but the new area planned lags behind practical requirements,and there is an obvious insufficiency of limiting human activities in that area of Guangzhou.Besides,coordination between two regions also limits the effectiveness of conservation area of water supply;2)The quantitative structures of land use in secondary conservation area and prearrangement area are different.In secondary conservation area, construction land area takes the biggest proportion of land use and cultivated land takes the second place while the area structures of the two types of land use in the prearrangement zone are just reverse.It means that when we take measures to protect water quality for the two different areas, we should concern about different pollution sources;3 )The characteristics of landscape of land use show that land use patterns are difference in various areas.The differences between indices of FRAC_MN and COHESION are small,but appear quite significant between the indices of SHDI and PD.The characteristic variation of batch shapes was small,but the characteristic difference of landscape fragmentation was significant.What is more,these above results also reveal that human activities in the conversation areas are still intense.Therefore,it is absolutely necessary and important to take measures to protect water source areas and water quality,so that urban ecological security can be guaranteed.