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In order to explore the effects of 2 kinds of biomass improver, corn straw and EM inoculants on soil erosion factors (rainfallerodibility R and soil erodibility K) in southwest China, this paper used the micro plot (1 m x 1 m) and unified the slope, used 2 kinds of biomass improver in ration and set the original soil to observe and analyze the changes of runoff and sediment and the changes of physical and chemical properties on soil. The results show that both of the 2 improved methods compared with original soil have the function of reducing soil erosion: in the rainy season (from June to October), soil erosion under the straw returning to field decreases by 52. 8%, 53%, 63%, 62. 1% and 63. 5% respectively, and soil erosion under the microbial inoculant application decreases by 34%, 33. 9%, 43. 7%, 39. 2% and 41. 3% respectively; percent of soil erosion degree: straw returning to field < microbial inoculant application < original control, soil erosion amount and soil erosion factors show good correlation, the ranges of correlation coefficient are 0. 733 7-0. 993 1 and 0. 692 1-0. 974 3 respectively, and the 2 different ways of straw returning and microbial inoculant application can significantly reduce K value, the numerical ranges are 0. 215 8-0. 249 6 and 0. 297 9-0. 320 4 respectively. The comprehensive analysis shows that the soil erosion and soil erosion factors are significantly correlated with the biomass improvement and the effect of R on soil erosion in the center of Yunnan Province is greater than that of K; 2 kinds of biomass soil improvement methods can effectively enhance soil corrosion resistance and the consolidation effect of straw returning to field is greater than that of the microbial inoculant application. [ABSTRACT FROM AUTHOR]

This paper selected the representativephreatic water lever data of 5 monitoring stations in Taiyuan alluvial plain area. It identified those data’s trend, persistence and mutation by using linear trend estimation and Mann-Kendall mutation test method. The results show that the groundwater level in Chengbei and Xigu stations is less fluctuated, while the water levels of Nangunian, Dajingyu and Lianglong stations are higher; the trends of groundwater level are declining in Dajingyu, Chengbei and Xigu stations and the decreasing rate is 0. 49 m/ a in Dajingyu where the rate is the greatest; the least decreasing rate is 0. 02 m/ a in Chengbei, while it is 0. 36 m/ a in Lianglong Station; Nangunian and Xigu stations show rising trend with the rate of 1. 09 m/ a and 0. 06 m/ a respectively; the M-K mutation test shows that the decline trend of Lianglong Station is significant, while the trends in the rest of stations are not significant. The mutation times in Nangunian, Dajingyu and Xigu stations occur in 2006, 2002 and 2003 respectively, while Chengbei and Lianglong stations have not mutation points. [ABSTRACT FROM AUTHOR]

This paper analyzed the spatial and temporal variation characteristics of the vegetation coverage based on FVC inversed by dimidiate pixel model using Landsat data of 2001, 2010 and 2015 in Zeku County of Three-River Source Region. The results indicate that the high vegetation coverage distributes in east and south, and the low vegetation coverage distributes in northwest. The vegetation coverage had been significantly improved in 2001-2015 and has the trend to medium and high coverage. The uptrend is mainly distributed in mid-east and the downtrend is mainly distributed in mid-north and southwest. The higher vegetation coverage grade gradually becomes the superiority landscape and the ecological engineering and the human activities of Three-River source region has some influence to the improvement of vegetation coverage of the study area. [ABSTRACT FROM AUTHOR]

The northern Xinjiang water supply project has been refilled as the largest caliber of fiberglass in China and the technical problems are very prominent, and the pipeline has high demands for raw materials, layers structure, manufacturing and construction and so on. This paper introduced the existing construction of partially inverted siphon project at home and abroad and studied the key technologies such as design parameter determination, pavement design, performance testing, production process, field test and whole process quality control of the glass steel pipe in this project and it had been studied in the cold region, with a diameter of 2. 5 m, the stiffness of the pipe was 8 000 N/ m2, the joint stiffness was more than 25 000 N/ m2 and the maximum allowable vertical deflection of the pipe was 3%. [ABSTRACT FROM AUTHOR]