Study on the dynamic changes of water quality and benthic community of rice-crab co-cropping model in saline-alkali land of Yellow River Delta
Setting 4 different culture densities of Eriocheir sinensis(0,0.45,0.68,0.90 ind/m2)in Dongying,and the changes of water and benthic community were studied.It provides theoretical basis for the construction and optimization of rice-crab co-cropping model in saline-alkali land.The results showed as follows:During the experiment,water temperature(T),dissolved oxygen(DO),total nitrogen(TN)and total phosphorus(TP)were firstly high and then low,which were obviously affected by seasonal changes.There was no significant difference in water indexes among different densities of Eriocheir sinensis(P＞0.05),which may be related to the obvious small culture density compared with the cultivated paddy area.The average annual water nitrogen and phosphorus content of rice and crab co-cropping system was significantly lower than that of rice single cropping system.And it is significantly higher than the single culture of aquaculture pond.The nitrogen and phosphorus absorption capacity of the co-cropping system was the highest in these three aquaculture models.Three species of benthic were detected during the experiment,which were Limnodrilus,Chironomid and Cipangopaludina.The main reason is that the sandy sediment of the Yellow River Delta is not suitable for their survival.The biomass was positively correlated with water salinity(P＜0.05)and negatively correlated with water PO43--P(P＜0.01).In conclusion,rice-crab co-cropping in the improved saline-alkali land has obvious ecological effects.
rice and crab co-croppingwater qualitybenthossaline-alkali landYellow River Delta
万方数据
维普
