In order to improve the yield and fertilizer utilization of the ricecrayfish rotation and direct seeding rice Nongxiang 32,the effects of different soil preparation and fertilizer application methods on the growth,yie...In order to improve the yield and fertilizer utilization of the ricecrayfish rotation and direct seeding rice Nongxiang 32,the effects of different soil preparation and fertilizer application methods on the growth,yield and fertilizer utilization of the variety were studied.The results showed that,under the rice-crayfish rotation and direct seeding farming mode,the contributions of seed setting rate,1000-grain weight,yield,and fertilizer contribution rate to yield of Nongxiang 32 in the treatments with rotary tillage with base fertilizer,rotary tillage without base fertilizer and no-tillage with base fertilizer were relatively higher than those in the treatments with rotary tillage without fertilizer,no-tillage without fertilizer and no-tillage without base fertilizer,and there were no significant differences between the three treatments.Rotary tillage with base fertilizer and rotary tillage without base fertilizer significantly increased the total number of stems and tillers,total number of ears,and number of effective ears.Rotary tillage and application of base fertilizer also significantly increased the number of tillers,plant weight and weed suppression ability in the early stage of rice growth.Therefore,in the different soil preparation and fertilizer application methods,the application of base fertilizer with rotary tillage was the best,followed by rotary tillage without base fertilizer and no-tillage with base fertilizer.展开更多
To determine the variation of water quality in rice-crayfish(Procambarus clarkii)integrated systems(RCIS)in China,eleven water quality parameters were measured monthly in a typical RCIS located in Qianjiang City(Hubei...To determine the variation of water quality in rice-crayfish(Procambarus clarkii)integrated systems(RCIS)in China,eleven water quality parameters were measured monthly in a typical RCIS located in Qianjiang City(Hubei Province)from July 2014 to June 2015,the parameters were analyzed with principal component analysis(PCA)and compared between the trenches and rice areas during the rice fallow period(Nov-May).The trench and rice area comprehensive results showed that pH(7.48-8.68),NH_(4)^(+)-N(0.2-1.09 mg/L),NO_(2)^(-)-N(<0.052 mg/L)and conductivity(435-951μS/cm)were within the suitable ranges for P.clarkii and that turbidity(TU)was high during the crayfish harvesting and rice planting season.Annual averages of total nitrogen(TN),total phosphorus(TP),permanganate index(CODMn),and chlorophyll a(Chl.a)content were<2(except in Nov-Dec),0.25,10 mg/L,and 50 mg/m^(3)(especially in Nov-May,<10 mg/m^(3)),respectively.Dissolved oxygen(DO)was below 4 mg/L in Mar-Sep,with a minimum of~1 mg/L,and much higher in Oct-Feb.The maximum and minimum monthly average water temperature(WT)were 31.4°C in July and 5.7°C in December,while the maximum and minimum instantaneous WT were 39.7°C and 2.5°C,respectively.PCA analysis showed that the first three axes,which were mainly correlated with DO,WT and nutrient level,described most information of the parameters,and parameters showed seasonal changes.Some differences were observed in water parameters between the trenches and rice areas,i.e.,trenches generally had higher TU,WT and DO,and lower TN,TP and CODMn,although no significant differences were found in some months and some parameters.The study revealed relatively low water nutrient level,probable extreme WT and DO level in some seasons,and certain differences between the trenches and rice areas in typical CRIS in China.Accordingly,some measures should be taken to improve the negative parameters:1)enhance the water fertility;2)increase DO,especially in Mar-Sep;3)increase the trench and water depth to avoid extreme WT.And water quality management should be addressed in both trenches and rice areas.展开更多
文摘In order to improve the yield and fertilizer utilization of the ricecrayfish rotation and direct seeding rice Nongxiang 32,the effects of different soil preparation and fertilizer application methods on the growth,yield and fertilizer utilization of the variety were studied.The results showed that,under the rice-crayfish rotation and direct seeding farming mode,the contributions of seed setting rate,1000-grain weight,yield,and fertilizer contribution rate to yield of Nongxiang 32 in the treatments with rotary tillage with base fertilizer,rotary tillage without base fertilizer and no-tillage with base fertilizer were relatively higher than those in the treatments with rotary tillage without fertilizer,no-tillage without fertilizer and no-tillage without base fertilizer,and there were no significant differences between the three treatments.Rotary tillage with base fertilizer and rotary tillage without base fertilizer significantly increased the total number of stems and tillers,total number of ears,and number of effective ears.Rotary tillage and application of base fertilizer also significantly increased the number of tillers,plant weight and weed suppression ability in the early stage of rice growth.Therefore,in the different soil preparation and fertilizer application methods,the application of base fertilizer with rotary tillage was the best,followed by rotary tillage without base fertilizer and no-tillage with base fertilizer.
基金This work was financially supported by the Special Fund for Agro-scientific Research in the Public Interest(No.201203081)the R&D Program of the Ministry of Science and Technology of China(Nos.2012BAD25B06 and 2015BAD13B02).
文摘To determine the variation of water quality in rice-crayfish(Procambarus clarkii)integrated systems(RCIS)in China,eleven water quality parameters were measured monthly in a typical RCIS located in Qianjiang City(Hubei Province)from July 2014 to June 2015,the parameters were analyzed with principal component analysis(PCA)and compared between the trenches and rice areas during the rice fallow period(Nov-May).The trench and rice area comprehensive results showed that pH(7.48-8.68),NH_(4)^(+)-N(0.2-1.09 mg/L),NO_(2)^(-)-N(<0.052 mg/L)and conductivity(435-951μS/cm)were within the suitable ranges for P.clarkii and that turbidity(TU)was high during the crayfish harvesting and rice planting season.Annual averages of total nitrogen(TN),total phosphorus(TP),permanganate index(CODMn),and chlorophyll a(Chl.a)content were<2(except in Nov-Dec),0.25,10 mg/L,and 50 mg/m^(3)(especially in Nov-May,<10 mg/m^(3)),respectively.Dissolved oxygen(DO)was below 4 mg/L in Mar-Sep,with a minimum of~1 mg/L,and much higher in Oct-Feb.The maximum and minimum monthly average water temperature(WT)were 31.4°C in July and 5.7°C in December,while the maximum and minimum instantaneous WT were 39.7°C and 2.5°C,respectively.PCA analysis showed that the first three axes,which were mainly correlated with DO,WT and nutrient level,described most information of the parameters,and parameters showed seasonal changes.Some differences were observed in water parameters between the trenches and rice areas,i.e.,trenches generally had higher TU,WT and DO,and lower TN,TP and CODMn,although no significant differences were found in some months and some parameters.The study revealed relatively low water nutrient level,probable extreme WT and DO level in some seasons,and certain differences between the trenches and rice areas in typical CRIS in China.Accordingly,some measures should be taken to improve the negative parameters:1)enhance the water fertility;2)increase DO,especially in Mar-Sep;3)increase the trench and water depth to avoid extreme WT.And water quality management should be addressed in both trenches and rice areas.
