Wetlands are playing important roles in flood control, groundwater recharge, climate improvement, air purification and regional ecosystem balance maintenance. With the increasing activities of human interferences and the surrounding environment, the global and China's wetland ecosystems have been seriously damaged in their ecosystem services. Therefore, a reasonable assessment of wetland ecosystem service value helps to accurately quantify the cost of protection and utilization of benefits, maintains wetland ecosystems healthy and stable, and provides a scientific basis for the rational development of wetland resources. Since wetland ecosystem service functions mainly refer to direct impacts on humans, measurements of the value of ecosystem service is better to convert it to "monetary value", so as to gain accurate value based on supply and demand, predictable input and output or different management approaches.
Researches on the contemporary wetland ecosystem service valuation methods can be divided into two categories: researches on calculation methods based on common service categories and researches on wetland ecosystem service category from the point of wetland ecosystem functions and services supply processes. However, due to different valuation methods, perspectives and objects, a decisive valuation method hasn't yet formed, which also leads to great differences in calculating results. It is quite convincing that spatial and temporal lagging and double counting problems in wetland ecosystem service valuation have many uncertainties in calculations when adopting contemporary methods.
Therefore, this paper put forward a multi-dimensional valuation method -Time Dimension, Spatial Dimension and Emergy-Economy Dimension, based on the definitions, categories and beneficiaries of wetland ecosystem services. Time Dimension mainly focused on temporal lagging in subjects of wetland ecosystem service valuation. Spatial Dimension described all the "beneficiaries" of wetland ecosystem service in different service areas. Emergy-Economy Dimension adopted both the methods of biophysics and economy. Meanwhile, clarifications of the advantages of this method in accurately quantifying ecosystem service value and in avoiding spatial and temporal lagging and double counting problems were also discussed in this paper, so as to provide further references for other ecosystem. Finally, an example of Balihe wetlands in Huaihe River Basin was given to provide further explanations of this method.