Study On Plant And Aquaculture Coupling Agriculture System

Centralized and high-intensive aquaculture ponds had brought excess organic matter load to the aquaculture water because of the large remnant baits, excrements and dead bodies, which made the aquaculture water deteriorate. Changing the water could result in tremendous environment pressures to the coastal water in the farming districts. And our country current have no related laws to control the farming wastewater discharge, and also have no satisfactory treatment technology of wastewater in marine culture that conformable to Chinese conditions. On the whole, aquaculture wastewater was discharge without any treatments. For alleviating the increasingly serious aquaculture sea water pollution problems, this research proceeded to monitor the water quality index of the mariculture ponds about the basic water circumstances, and studied the light treatment system to purify aquaculture wastewater. Sieving the saline tolerance plant to regulate aquaculture water, to develop sea water plants and aquacultures coupling agriculture system mode, provide the support of the foundation theories to the improvement and perfect of closed poly-culture. The chief results are showed as follows:1. Along with the increase of farming time, the nourishments (nitrogen, phosphorus et al.) accumulate too many in aquaculture ponds because of the continuously supply of baits, which result in eutrophication. The phytoplankton large quantity breeds, the primary production of phytoplankton also increases, the variety ranges of DO and pH in the water day and night increases. The longer farming time, the more accumulated organic matters in pond bottom because of the sediment of remnant baits, excrements and dead bodies. The organic matter in bottom can generate CO₂, H₂S, Amm-N and so on by heterotrophic bacterial decompose and conversion, making the water pH present the descendent trend. The few indexes have great representative, the variety of the water quality factors reflect the basic circumstance of water. It is very significant to guide the aquaculture and treat the wastewater.2. The system of light treatment had obvious purifying effect in treating the aquaculture wastewater, the removal rations of the chief pollution of NO3-N, NO2-N, Amm-N, TP were high. The average removal of NO₃-N, NO₂-N, Amm-N, TP, COD of...