Research on the Energy Analysis of Lake Ecological Functions

The energy flow and material flux of Poyang Lake ecosystem were quantitatively analyzed in this paper under the direction of energy analysis theory of eco-economic system established by H. T. Odum. In the process of traditional energy flow analysis, emergy values of different natures and different types can not be compared with each other or calculated easily. While based on the theory and method of energy analysis, fluxes of energy, material, value and population can be analyzed quantitatively with a uniform measurement standard. In this article, such conclusion was obtained that 4 steps necessary for the energy analysis of Lake´ s ecological benefits were that: (1) conceptual energy analysis system should be built up, which can reflect the energy analysis method; (2) energy analysis table should be drafted out and the emergy values should be calculated; (3) energy indices should be estimated; (4) wetland ecological benefits should be expatiated according to analytical tables of energy indices system and energy schemes. By collecting field investigating data and historical information, using the method listed in this article and analyzing the energy schemes and tables of lake ecosystem, we got that in 2005 the solar energy input was 2.75 × 10¹⁹ sej, solar energy output was 6.90 × 10²⁰ sej, the primary productivity is 4.51 × 10¹⁹ sej, the solar emergy values of ecological service, ecological tourism and research work in the input/output system are 7.79 × 10¹⁹ se, 6.86 × 10¹⁹ sej and 2.01 × 10¹⁹ sej respectively, and the sum was 1.67 × 10²⁰ sej. The total value of the natural resources in Poyang Lake was 1.03 × 10⁹ Em$.