Advanced Materials Research Vols. 726-731

Abstract: Ground surface subsidence will cause enormous impact to ecological environment in Coal Gob. But the study concerning the effect of the surface subsidence on soil nutrients is little. Taking Bulianta (Sandstorm--subsidence Area) and Yujialiang (Loess-subsidence Area) coal mine in Shenfu-Dongsheng coal field as study object, The characteristics of soil nutients in non-collapse area and the effect of collapse on soil nutrients are sdudied systematicly by Field sampling and laboratory analysis.The results showed that: With the increasing of soil depth, total soil nutrient content gradually reduced in both stduy areas, While in Sandstorm-subsidence Area, Total nitrogen and total phosphorus increased with soil depth. The total nitrogen and total phosphorus in Sandstorm-subsidence Area is lower than those in Loess-subsidence Area, but the total K is higher than that in Loess-subsidence Area. In a word, the effect of coal mining subsidence on total soil nutrients in both Areas is on the small side.

Abstract: For the last decades, because of increasing attention to global change, the carbon cycle in the terrestrial ecosystem has become a hotspot problem for every country. It has 1.6 Pg/a C to release into atmosphere because of the irrational land-use, quickening the step of global warming trend. But agricultural soil has the double-sword effects. If improper soil tillage practices are adopted, agricultural soil may become the source of carbon dioxide in the atmosphere. And if adopting effective management measurement and scientific tillage technology, agricultural soil may become carbon sink. This paper reviewed the effects of conventional tillage and conservation tillage on soil organic carbon (SOC), and found that conservation tillage has a huge potential for sequestrating organic carbon compared with conventional tillage. Finally, the important significance of agriculture soil carbon sequestration was discussed in detail.

Abstract: This study focuses on the outstanding issues of the serious lack of water resources in semi-arid area of western Liaoning province. Traditional cropping patterns as contrast, studied the effect of unary or binary coverage of three micro-catchment patterns, which were ridge film mulching and furrow seeding (T1), groove ridge mulch film (T2), ridge ditch straw mulching cultivation (T3). Compared with the traditional pattern, micro-catchment patterns have obvious water gathering effect. This experiment, T2 of the best water conservation and water harvesting, compared to the traditional pattern, the average soil moisture content improve 2.38% in the growth period. Followed by T3, improves 1.71%. The third was Tr1, improve 1.43%. Micro-catchment can be avoided the drought of soil deeply by covering mulching film. 63mm precipitation can effectively improve 0-80cm soil moisture. While gullies covering film or direct planting cultivation can significantly increase soil temperature. Although the straw covering did not have the role to increase the soil temperature, the soil temperature was more close to the traditional cropping pattern. Compared with the traditional pattern, the average soil temperature of T2 increased by 2.42°C, T1 increased 1.99°C, T3 reduced 0.21°C.

Abstract: Four kinds of protective measures and three contrast measures were chosen on Harbin-Suifenhe highway to analyze the effects of different types of soil and water conservation measure on highway side slope soil. The results showed that Soil and water conservation measures of highway side slope increased water holding capacity and soil conservation capacity significantly. The saturated water holding capacity, capillary water holding capacity and field water holding capacity of E, PP grid measure were 1.79 times,1.60 times and 1.62 times respectively of that in contrast 1 measure. E, PP grid measure, resin network measure and spread planting measures reduced runoff 58.5%, 59.3% and 50.8% compared with contrast measures. Consider of landscape and cost factors, spread planting measures was recommended to use on the smaller slope degree of highway side, E, PP grid measure, resin network measure were recommended to be used on the steep slope of highway side, hex hollow brick measure was not recommended.

Abstract: Eight enzyme activities involved in N and P cycling and soil basic properties influenced by four years of nitrogen (N) deposition were investigated under a semi-arid grassland soil, Northern China. Results showed that N addition into soil could cause soil acidification significantly. Inorganic dissolved N (NH₄⁺N and NO₃N) concentration increased significantly while Olsen-P concentration changed slowly with simulating N deposition. Soil nitrification potential, protease, nitrate reductase, and phosphodiesterase activities were repressed by higher rate of N deposition caused by higher NH₄⁺ concentration or soil acidification. Soil alkaline phosphomonoesterase activities correlated positively with soil pyrophosphatase activities due to the microbial origin of alkaline phosphatase and pyrophosphate. Positive correlation of acid phosphomonoesterase activities and soil TC was also observed in the study.

Abstract: Water and soil resources are important material basis, upon which human subsistence and development are relying. In the meantime, they are also the fundamental conditions for agricultural production. With the development of human activities and irrational exploitation of water and soil resources, the problem of water loss and soil erosion has caught the attention of the world. Water-loss and soil-erosion dominated non-point source pollution in agriculture, due to its very nature of direct combination with regional food security and ecological safety, is now ascending to a problem of regional-resources. This paper firstly introduced the definition and characteristics of water-loss and soil-erosion dominated non-point source pollution. Secondly a technical framework which was primarily supported by simulation of non-point source pollution in regional agriculture, identification of the mechanism for water-loss and soil-erosion dominated non-point source pollution and the scheme against it is established. Finally key issues such as load module construction for semi-distributed non-point source pollution which based upon component structure, theory and method for total quantity control, and charting the sets of solutions and countermeasures were discussed. The paper may help to establish a theoretical foundation for later research.

Abstract: This article takes four different slope lands as the experimental points in Jinsha River dry-hot volley. The double-rings method is adopted to illustrate the soil moisture infiltration characteristics in four different landuse types. The results show that different landues types have obvious differences in soil infiltration capability among four different patterns of landuse. Arbor forest behaved the best infiltration capability and wasteland the worst; the average infiltration and the steadily infiltration attains 1.67mm/min and 0.5mm/min respectively during the first 120min of soil water infiltration process in arbor forest; the rate of whatever the average infiltration or the steadily infiltration express the same regulation: the arbor forest is a little higher than the shrub land, the grassland, than the waste land; the moisture infiltration rate in different landuse types can all be thoroughly defined through the Horton equation; Water infiltration is affected by the soil bulk density. With the bulk density increasing, the steady infiltration rate decreases. And the two are at an exponential function.

Abstract: In order to clarify the influence of saline water irrigation to plant growth and distribution ofsoil water-salt, and providing theoretical basis for sustainable water supply of ecological constructionin desert area, the data of soil water-salt and plant growth was observed at Tarim Desert HighwayShelter-forest Ecological Project No. 17 well. The law of soil water and salt spatial distribution wasanalyzed, and the responses of plant growth to 4 different irrigation amounts were studied by singleelement variance analysis. The results were as follows: the soil water content reaches or is close tosaturation in layer of 100~120cm under the 420mm irrigation water condition; The soil water contentreaches or is close to saturation in layer of 160~180cm under the 233.1mm irrigation water condition;The soil water content reaches or is close to saturation in layer of 180~200cm under the 285.6mm irrigation water condition; The soil water content reaches or is close to saturation in layer of160~180cm under the 201.6mm irrigation water condition. The vertical distribution law of soilssalinity is that the soil salt can enter groundwater after 3 days of irrigation, and be gathered in 0~30cmsoil layer. There were no significant differences except the Tamarix plant height in plant growthindexes among 4 different irrigation quantities treatments.

Abstract: At present, there are only a few theoretical models for researching the electrical resistivity characteristics of multi-phase soil-stone composite medium, as it could be influenced by so many factors. Based on the theory structure models of unsaturated soil electrical resistivity put forward by previous researchers, a theoretical model of multi-phase soil-stone composite medium electrical resistivity properties, suitable for both series connection structure and parallel connection structure of soil stone mixture, is proposed, through which the regular patterns under the influence of water content, porosity, soil-rock ratio, and saturation are analyzed. In line with the results, when the composition of particles are not changed, in the order of sensitive, the main factors that affect electrical resistivity characteristics are water content, porosity, and soil-rock ratio.

Abstract: To provide theoretical basis for vegetation construction surrounding coal mining subsidence crack in semi-arid region, the focus of studying is on the soil moisture surroundings, the coal mining crack in different widths and soil moisture on different directions of a single crack. The result shows that the greater crack width is, the greater influence on soil moisture, the greater influence on deep soil moisture are. The standard deviations of soil moisture at each distance are crack width 0-20cm< width 20-40cm < width 40-60cm < width>60cm. Soil moisture along the crack direction has no obvious distribution regularity, on the vertical crack strike, and within a certain distance, with the increase of distance between crack, the tendency of soil moisture content is increased.