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Long-term intensive use of mineral fertilizers in double rice-cropping systems has led to soil acidification and soil degradation. Manure fertilization was suggested as an alternative strategy to mitigate soil degradation. However, the effects of long-term mineral and manure fertilization on rice grain yield, yield stability, soil organic carbon (SOC) content, soil total nitrogen (TN) content, and the underlying mechanisms are unclear. Based on a long-term experiment established in 1981 in southern China, we compared four treatments: no fertilizer application (Control); application of nitrogen–phosphorus–potassium (NPK); NPK plus green manure in early rice (M1); and M1 plus farmyard manure in late rice and rice straw return in winter (M2). Our results showed that 37 years of NPK, M1, and M2 significantly increased rice grain yield by 54%, 46%, and 72%, and yield stability by 22%, 17%, and 9%, respectively. M1 and M2 significantly increased SOC content by 39% and 23% compared to Control, respectively, whereas there was no difference between Control and NPK. Regarding soil TN content, it was significantly increased by 8%, 46%, and 20% by NPK, M1, and M2, respectively. In addition, M2 significantly increased bacterial OTU richness by 68%, Chao1 index by 79%, and altered the bacterial community composition. Changes in soil nutrient availability and bacterial Simpson index were positively correlated with the changes in grain yield, while shifts in bacterial community were closely related to yield stability. This study provides pioneer comprehensive assessments of the simultaneous responses of grain yield, yield stability, SOC and TN content, nutrient availability, and bacterial community composition to long-term mineral and manure fertilization in a double rice-cropping system. Altogether, this study spanning nearly four decades provides new perspectives for developing sustainable yet intensive rice cultivation to meet growing global demands. [ABSTRACT FROM AUTHOR]

ABSTRACT: The risk analysis of urban rainstorm water logging facing Tianjin city by using methods of probability, investigation and numerical simulation was carried out in this article. Firstly, a mathematical model for the urban rainstorm water logging was established on the basis of one- and two-dimensional unsteady flow theory and the technique of non-structural irregular grid division, Secondly, the precipitation over heavy rain was divided into seven grades, the experiential expression of frequency and rain grades was got according to the observed rainfall from May 1918 to October 1998. Thirdly, the mathematical model was used to simulate various rain process according to the features of the rainstorm and the draining rule, based on the simulated maximum water depths, 3 class of disaster extents were established, the disaster risks were mainly in Class I and Class II, The risk analysis of water logging on traffic were primarily evaluated, and finally, some management and mitigation measures of the urban rainstorm water logging disaster were discussed. [Copyright &y& Elsevier]

ABSTRACT: The risk analysis of urban rainstorm water logging facing Tianjin city by using methods of probability, investigation and numerical simulation was carried out in this article. Firstly, a mathematical model for the urban rainstorm water logging was established on the basis of one- and two-dimensional unsteady flow theory and the technique of non-structural irregular grid division, Secondly, the precipitation over heavy rain was divided into seven grades, the experiential expression of frequency and rain grades was got according to the observed rainfall from May 1918 to October 1998. Thirdly, the mathematical model was used to simulate various rain process according to the features of the rainstorm and the draining rule, based on the simulated maximum water depths, 3 class of disaster extents were established, the disaster risks were mainly in Class I and Class II, The risk analysis of water logging on traffic were primarily evaluated, and finally, some management and mitigation measures of the urban rainstorm water logging disaster were discussed. [Copyright &y& Elsevier]

We aimed to explore changes in basic soil productivity (BSP) under different fertilization regimes in the Poyang Lake region, Jiangxi Province, China. Soil samples were collected from a long-term fertilization experiment (since 1981) that included treatments of no fertilization (CK), chemical fertilization (NPK), and combined chemical and organic fertilization (NPKM). Then, a three-year pot experiment (from 2012 to 2014) with double rice cropping was conducted with two different fertilization regimes (no fertilization, F 0 ; fertilization, F 1 ) using CK, NPK and NPKM soils. Grain yield and BSP were analyzed among soils with different fertilization regimes to identify the key factors driving changes in BSP. Results showed that grain yields in NPKM soil were higher than in NPK and CK soils regardless of fertilization in the pot experiment. Under the F 0 condition, annual grain yields of NPKM soil were 37.7%-143.9% and 20.8%-66.7% higher than CK and NPK soils, respectively. The BSP values of CK, NPK and NPKM soils in three years were 41.8%-53.1%, 45.2%-62.6% and 59.1%-88.1%, respectively. NPKM soil had significantly higher BSP than NPK and CK soils. Furthermore, there were significant positive correlations between soil organic matter and BSP as well as between organic carbon balance and BSP. These results suggested that long-term application of chemical and organic fertilizers could improve BSP in the double rice cropping system of the Poyang Lake region. In addition, soil organic matter and organic carbon balance are important factors for improving BSP in this region.

Objective: To understand the status of schistosomiasis knowledge and behavior and analyze the regional difference of population in Mianzhu City., Methods: Nine towns were divided into 3 groups, and each group had 3 towns. In Group I , there were 5 or more than 5 advanced schistosomiasis patients each town; in Group II , there were 1-4 advanced patients each town; in Group III, there was no advanced patient. A total of 2 743 residents were investigated with questionnaire in all the 9 towns., Results: The overall awareness rate of schistosomiasis control knowledge was 88.12%, and the awareness rates of schistosomiasis control knowledge were 94.55%, 88.21% and 81.10% in Group I , Group II and Group III respectively. The total formation rate of correct behavior was 68.10%, and the formation rates of correct behavior were 73.18%, 67.05% and 63.65% in Group I , Group II and Group III respectively. The awareness rates of schistosome transmission were 95.99%, 89.48% and 79.67%; the awareness rates of Oncomelania snails were 87.67%, 82.54% and 73.92%; the awareness rates of schistosomiasis harm were 95.68%, 93.99% and 80.88%; the rates of residents who thought that schistosomiasis patients did not affect others were 9.97%, 12.83% and 15.58%; the rates of residents who did not know the information of the snails should report to which department were 7.91%, 11.33%, 15.69%; the rates of residents who often had wild bowels were 6.17%, 8.79% and 11.38%; the rates of residents who often washed their hands and feet in ditches and ponds were 58.68%, 58.27%, 61.22%; the rates of residents who would not accept the schistosomiasis checks were 5.86%, 5.66%, 11.49% in Group I , Group II and Group III respectively., Conclusion: As a whole, the population of Mianzhu City has positive behaviors to schistosomiasis control. We should still enhance the schistosomiasis control education and interventions according to the characteristics of the different townships.