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The Yangtze River is an important production base of China's aquatic products, pond culture is the most important supply of aquatic products. Most pond culture has been the fertilizer fish, low utilization of nitrogen and phosphorus fertilizer breeding process, resulting in large amounts of nitrogen, phosphorus deposited in the pond sediment and lost to the surrounding lakes and rivers. The same time, the major fertilizer-based farming feeding object is carp, bighead carp and grass carp, compared with non-traditional fishing unit area of ??lower economic output. From the point of view of wetland environmental protection and sustainable use of wetland resources in Hubei Province from March 2004 to December 2005 Zhangdu Lake Wetland experimental pond field sampling and monitoring and laboratory analysis. From pond fish culture throughout the growing cycle analysis and comparison of three treatments three parallel herring and blunt snout bream A mode, B-mode mainly to grass carp and silver carp, bighead-based C mode fish stocking, growing, harvesting, changes in water quality and economic efficiency. Material balance method, analysis and comparison of the A, B, C three species of fish farming model into the drainage, fish stocking, feed inputs, fertilizer inputs, forage inputs, into a fish pond fish farming throughout the growing cycle. harvest nitrogen, phosphorus input and output to calculate the various modes of nitrogen, phosphorus utilization and loss. Calculated according to the balance of payments of the the three parallel experiment Lianchi nitrogen and phosphorus transfer, calculated based on the input-output experimental pools economic income, monthly analysis of the physical and chemical the experimental Lianchi water quality indicators and total nitrogen in the sediment, ~ 5cm, 5 ~ 10cm, 10 ~ 50cm and total phosphorus, 0 ~ 5cm, 5-10cm, 10 to 50 cm of the content. The main results and conclusions are as follows: the the wetland pond fish culture A mode ZHANGDU herring, blunt snout bream fish production was 7941 ± 165 1011 ± 23 kg (mean ± standard deviation) kg / ha, B-mode / ha, C mode for 717 ± 10 kg / ha, there is a significant difference (P lt; 0.05) between the mode A, B, C mode; A mode of silver carp, bighead carp and other filter-feeding fish production was 5211 ± 97 kg / ha, B-mode 6094 ± 273 kg / ha, C mode of 8110 ± 185 kg / ha, mode A and B, C mode there is a significant difference (P lt; 0.05); B mode grass carp production to 3378 ± 177 kg / ha, C mode is 2351 ± 24 kg / ha, there is a significant difference (P lt; 0.05) between the two. A mode of economic benefits 31268 ± 1100 yuan / ha, B-mode 15213 ± 2257 yuan / ha, C mode 12042 ± 462 yuan / ha, there are significant differences (P between mode A, B, C mode lt; 0.05). A mode output input ratio of 1.38 ± 0.01 to 1.30 ± 0.04 B mode, C mode and 1.23 ± 0.01, there is a significant difference (P lt; 0.05) between the mode A, B, C mode. The three pond fish farming mode A mode of nitrogen loss average of 1064.19 kg / ha, B
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