Advanced Materials Research Vols. 864-867

Abstract: An experiment was conducted to study the physiological and ecological characteristics of the main sand-fixing tree species in Horqin sandy land in order to explore the adaptabilities of tree species to semi-arid environment. The leaf water potential (LWP) and root distribution of ten sand-fixing tree species were measured and compared, and the preferred species were chosen for restoring degraded sand dunes in Horqin sandy land. These results are useful for evaluating the ability of the drought resistance of these species, and have some important implications for establishing artificial plantations that have high stability.

Abstract: Soil sampling was carried out on the experimental plot, and comprehensive analysis of characteristics of soil nutrient and physical and chemical environment based on the soil and water conservation monitoring site topography and vegetation etc., on the basis of present situation investigation. The plant selection analysis of different experiment plot was carried out combined with experiment village construction planning, and the plants by nature, on the basis of the different soil and water conservation monitoring sites have in common in Zhejiang province. Targeted put forward of the construction of the proposed plant and soil improvement measures, for each monitoring site experiment plot of provide the scientific basis for the establishment of soil and water conservation measures.

Abstract: Took the Pinus yunnanensis forest as the research object, and took planted forest for control, carried on a research in soil physicochemical properties of different forest ages of Pinus yunnanensis. The results show that: For secondary forests at different ages, (1) middle-aged forest has the smallest soil bulk density and largest soil natural water content. Compared with the same age planted forest, secondary forest has smaller soil bulk density and larger soil natural water content.(2) Middle-aged forest has the smallest soil pH value, and the tallest total nitrogen content and soil organic matter in the 0-20cm soil layer. Compared with the same age planted forest, secondary forest has smaller pH value. While its soil organic matter and total nitrogen content are more than planted forest significantly.(3)There is an extremely significant negative correlation among pH value, soil organic carbon and total nitrogen content; while an extremely significant positive correlation between soil organic carbon and total nitrogen content.

Abstract: With dry sieving and wet sieving methods, we studied the distribution characteristics and stability of the aggregates in the typical orchard soils with different cultivation years in northern China under long-term freezing-thawing conditions. The results show that: the contents of the aggregates with particle size above 10 mm or between 0.25 and 10 mm are significantly increased with cultivation years and annual growth rates were respectively 1.28% and 0.078%. Fractal dimension in the orchard soils was gradually decreased and lower than that in uncultivated area near the orchard in corresponding cultivation year. MWD of orchard soils shows annual increasing trend of 0.76%. The content of the water stable macro aggregates in orchard soils was increased with the cultivation years and was about 11.65%-20.18% higher than that of uncultivated soils near the orchard. Average annual growth of orchard soils was 0.37%. Fractal dimension was decreased year by year on the water stable macro aggregates. MWD of the water stable macro aggregates was significantly greater than that of uncultivated soils near the orchard and increased with cultivation years. Aggregate destruction rate was gradually decreased to 31.61% of that in the 60^th year and annual average decrease rate was 0.91%. Soil bulk density was gradually decreased.

Abstract: This paper use 2007 and 2010 SPOT-5 images as a data source, combined with RS and GIS technology, introduced the concept of hemeroby, developed a suitable landscape classification system in Ximen Island, systematically evaluated the dynamic changes of hemeroby of Ximen Island marine Protected Areas. The results indicated that from 2007 to 2010, the ecological environment of Ximen Island has gradually improved. Completely disturbed landscape type decreased sharply in total area, while undisturbed types were increased a lot. From the perspective of total characteristics of the spatial distribution of hemeroby index, the residential , traffic land and landscape surrounding anthropogenic interference with the highest index.

Abstract: The concentration and distribution of metal (Mg, K, Ca and Na) elements in agricultural and non-agricultural soils were investigated in upstream of the Pearl River, China. The result showed that total Mg, K, Ca and Na concentrations in agricultural soils were higher than those in non-agricultural soils, indicating that agricultural input, such as water irrigation, fertilizer and pesticide application, may have led to the accumulation of Mg, K, Ca and Na in agricultural soils. Total concentrations of the metal elements in agricultural and non-agricultural soils were compared with the background values of Yunnan soil, the result showed Mg, K and Na were lower in both agricultural and non-agricultural soils in the study area, while Ca was relatively higher, which were possibly due to Karsts geographic environment in the study area.

Abstract: This study sampled and tested the soil samples in wind power station of Huitengxile. Analyze soil bulk density in the different space and time and study the effect of wind power station on soil bulk density in different space and time. Results show that the mean soil bulk density of each year has the tendency of increase with the increase of depth in the range of 0 to 50 centimeters, but the increase extent is not much. The increase of soil bulk density in deep soil layer is the biggest in 1996 and the smallest in 2009 comparing that in the surface soil. The soil bulk density in the range of 0 to 40 centimeters is without obvious change regularity contrasting the control samples. The soil bulk density of control sample is greater than other experiment samples in the range of 40 to 50 centimeters. The change of topsoil soil bulk density is not significant with the increase of wind power station production time in the 10 to 30 centimeters. The change of soil bulk density is significant with the increase of wind power station production time at the depth of 40 to 50 centimeters. The mean soil bulk density takes the trend of decrease with the distance increasing from the wind power station base in different production time. The trend of mean soil bulk density is decreasing more significant in range of 0-60 meters. The change of mean soil bulk density is not big in the range of 80 to 100 meters from the base, and the value of soil bulk density trend to stability. It has not significant change contrasting the mean soil bulk density of different direction. The electricity generated by wind power has not effect on the direction of soil bulk density.

Abstract: Data of natural vegetation coverage in the Central Asia and Xinjiang of Chinese in 2005 was obtained by statistical analysis on MODIS Land cover data, then the ecological water requirement (EWR) of natural vegetation was brought out which based on the evapotranspirtation (ET) retrieval using SEBS model and natural vegetation areas. Results showed that the total EWR of wood land and grass land during the 2005 growing season was 70.10×10⁸m³ and 3251.91×10⁸m³,respectively. It is applicable for reference in the project of regenerating ecology and rationally redistributing water resources in arid areas.

Abstract: A village-scale approach was developed to break the cycle between desertification and poverty by providing sustainable employment and income, promoting environmental restoration by reducing water consumption, and integrating poverty amelioration with environmental restoration to ensure that solving one problem does not create new ones. The advantages of high-efficiency water-saving planting, a profitable livestock system, a sand-processing industry, and sand control and afforestation are integrated into what we call the Zhengxin pattern, which offers overall ecological and environmental benefits superior to those of competing approaches. The overall output efficiency of the Minqin basin water resources will increase threefold.

Abstract: Through laboratory experiments, the effects of adding different maize straw addictive and proportions in soil on the moisture evaporation characteristics were studied under the condition of different burial depth. Results showed that the relationship between soil moisture diffusivity and soil water content can nice described by an exponential function. Under the same soil water suction, soil water content of treatments with maize straw additive are all higher than pure soil. Between the treatments of soil with 3% maize cob and maize leaf, maize leaf treatment has a better water retention effect, but the difference is little in the treatments with 1% maize straw additive; maize leaf is superior to maize cob in the capacity of inhibiting soil water evaporation, and the treatment with 3% maize leaf in the depth of 0-5 centimeter soil layer can reduce soil moisture evaporation effectively. Keywords: maize straw addictive, soil water diffusivity, buried depth, accumulative soil water evaporation, soil water content