Abstract: In this paper,the data on water surface evaporation are analysed. The change of relative evaporation in windbreak network can be fitted by segmental curve, which includes two parts:the logarithmic one obeies natural logarithmic rule E_h/E₀=a₁+b₁lnh,and the second-degree curve one obeies second-degree curve rule,E_h/E₀=a₂h²十b₂h+c.Based on the characteristic study of horizontal distribution of evaporation,the mean relative evaporation intensity in windbreak network is estimated and the optimum distance space of sheltbelts for water reserve is discussed.

Key words: Shelter forest, Ralative evaporation, Horizontal distribution pattern, Distance space of sheltbets, emergy-ecological footprint approach, sustainability, northeast old industrial area., ecological coordination coefficient, ecological security