Advanced Materials Research Vols. 610-613

Abstract: Soil was sampled according to the distance surrounding different activities area and on different levels of travel channel around the gold saddle tourist spots of Xilamuren grassland in Inner Mongolia. Soil samples were collected every 5 cm until down to 30cm in each plot with soil wreath knife. Analyze soil compaction, bulk density, soil moisture content, pH, soil organic matter, available P, total N, total P and total K by experiment. Through data analysis, study the response of tourism interference on soil physical and chemical properties. Study shows that the destruction of tourism activities on the grassland soil is big and the intensity of tourism activities are positively correlated to the degree of interference. The nearer to the concentrated region of tourism spots facilities, the greater intensity of tourist disturbance and the greater damage of soil. The damage of soil in south side was significantly greater than that in the north side. Travel interference changes differently in different tourism activity area. The damage extent of interference in obo district and bok field was greater than that on both sides of horse tract. Different levels of travel channel showed that interference degree was different by the frequency size of vehicle rolling and the destruction of soil conditions was consistent with it. Tourism interference is relatively concentrated. It destructs the local environment. As long as the tourism point, tourism activity area, the layout of tourism road should not be spread too disperse and messy, the impact of grassland landscape pattern will be significantly reduced, and the deterioration trend of ecological environment is expected to be controlled. Through analysis of different type of tourism activities zone, basic cover all aspects of the impact of grassland tourism development on grassland environment. The changes of grassland soil could be explained driven by tourism disturbance. It can provide alternative methods for tourism interference study and provide guidance for the management of grassland tourist areas. Grassland tourist spots tend to be concentrated in the excellent area of pasture landscape resources and environment, but also the fragile area in ecological environment. The interference of human activities are extremely sensitive whether in a desert steppe zone of brown soil as matrix soil or in typical grassland zone of chestnut soil as matrix soil, and even in the meadow steppe of chernozem as matrix soil. Once vegetation is destructed, soil has been the strength trampling, sandy desertification would grow rapidly. It would not only affect pasture tourism, but also would threaten the neighboring regions. Therefore, it is necessary to study the effect of tourism interference on the soil of grassland tourist spots.

Abstract: Biological soil crusts cover 40% area of arid land, moss crust is a predominant species of biological soil crusts and plays important role in the fixation of C and N, prevention of soil erosion and infiltration of water into the deep soil; dew condense and water evaporation are indispensable aspects of water cycle in dry land. Although there were many studies about dew condense and evaporation of BSC, but no attention was placed on moss density like vascular plant. In this paper, measurements were taken to investigate the effects of crusted moss density on dew condense and evaporation. Dew amounts and evaporation were measured using micro-lysimeters. The results showed that moss density was positively related to dew condense, and negatively related with water evaporation, the thinner the moss density the higher the total evaporation amount; One-way-ANOVA analysis suggested that moss density had significant effect on dew condense, even very thinner moss crust had higher ability of dew deposition than bare soil.

Abstract: Immanent factors and change process in land degradation through soil degradation process is reflected, the main types of soil degradation are soil erosion and land desertification. This article take soil erosion as main degenerated form research land degradation intrinsic major effect factor. But soil erosion's major indexes are soil anti-scouring, soil anti-scouring macroscopic representation is soil anti-shear strength. How in situ testing, the quantitative reflection soil degradation's intrinsic factor is the soil degradation new problem. To solve this problem, the research and development has been able to reflect the soil degradation major effect factor the apparatus of mensurated soil anti-shear strength. This instrument has functions and so on man-machine interface, data storage, serial port communication, and uses the least square method analysis and digital filtering in order to the data analysis, the curve fitting. After and the traditional experiment's result contrast, has confirmed instrument's feasibility, the usability and the accuracy. Research on prevention of soil degradation in the main factors providing new ideas and concepts; can be a new index for monitoring soil degradation; and monitoring of soil degradation, provides a new technological means.

Abstract: Understanding the effects of land-use changes on soil property is crucial for the sustainable development in an agro-pastoral ecotone of China. Although grassland conversion is an important land-use change in northern China, most studies have focused on zonal grassland areas and the intrazonal grassland areas have been ignored, which is not climatic climax of natural grassland, because it is constrained by terrain, surface water, components of the earth surface and other ecological factors. The present study aims to determine the effects of the conversion of intrazonal grassland into cropland on soil properties in the Bashang area where a typical agro-pastoral ecotone of northern China is found. The results showed that intrazonal grassland conversion and subsequent tillage practices increased soil bulk density and decreased soil porosity, capillary moisture capacity, and soil nutrients content. Available soil zinc content in the study area was at extremely low level, which could not meet the need of crop growing based on the soil trace elements appraisal criteria of China. On the average, the conversion of intrazonal grassland into cropland led soil organic carbon density (SOCD) decreased from 22.49 kg m-2 to 13.24 kg m-2, and soil total nitrogen density (STND) from 2.23 kg m-2 to 1.27 kg m-2; that is, the meadow conversion resulted in a 41-43% reduction of SOCD and STND in 0–60 cm soil depth over about 20 years. To conserve the present status, the further conversion of grassland into cropland should be stopped, and encourage the restoration of cropped area into grassland to combat the soil desertification and degradation in the agro-pasturage ecotone of Northern China.

Abstract: The effects of an arbuscular mycorrhizal fungus, Glomus mosseae, on plant growth, soil aggregate stability, and rhizosphere carbon pools of young Citrus junos seedings were investigated with potted experiment in greenhouse. After three months of mycorrhizal inoculation, root colonization was 54.25%. Inoculation with G. mosseae significantly promoted plant height, stem diameter, leaf number, and shoot and root fresh weights. Colonization by G. mosseae significantly increased soil aggregate stability of the citrus rhizosphere through increase of mean weight diameter. G. mosseae could release a specific glycoprotein viz. glomalin into the rhizosphere as glomalin-related soil protein (GRSP). Meanwhile, mycorrhizal colonization was significantly positively correlated with two GRSP fractions. In stabilization of aggregate stability, in GRSP fractions only easy extractable -GRSP might contribute the role. The mycorrhizal symbiosis could increase soil organic carbon, hot-water extractable carbohydrates, and hydrolyzed carbohydrates concentrations, but the differences were not significant. Combined with the correlation analysis, it suggests that GRPS did not significantly regulate rhizospheric carbon pools, due to the short treated time (only 3 months).

Abstract: 1144 sample points were collected using PXRF from an area of 99 square kilometers soil area Zhehai town Huizhe county of Yunnan province to acquire their concentrations and possible sources, and characterize their spatial variability for risk assessment. SPSS16.0 was used to deal the raw date and eliminate the outfits and perform Multivariate analysis (correlation matrix, principal component analysis, and cluster analysis). It discriminate distinct groups of heavy metals. From the Range of the semi-variorum models, it obtained elements spatial structure and the contamination resource caused mainly by natural resource or anthropogenic activities. The result of risk assessment attained the percentage of pollution accounts for whole investigate region, which provides the reference to deal with the soil pollution.

Abstract: Variation in soil humus compositions (SHC) and the effect on soil acidity (SA) were studied in LOP of NE China. The results showed that for rhizosphere soil (RS) and non-rhizosphere soil (NRS), soil organic matter (SOM), carbon (C) in humic acid (HA) and humin increased from young stand (YS) to near mature stand (NMS) over ages, however, SOM, C in fulvic acid (FA) and humin decreased from NMS to mature stand (MS). Soil humification degree (SHD) were higher in secondary forests than in YS and NMS. As compared with young stand in the first rotation (YSFR), for RS, SOM, C in FA and humin decreased by 4.53%, 35.8% and 1.98% in young stand in the second rotation (YSSR), respectively, but for NRS, SOM, C in HA, FA and humin increased by 46.44%, 43.69%, 47.45% and 49.5%, respectively. Correlation between SHC and SA changed over ages. In RS, close correlation existed among SHC, active acidity (pH, AA), exchange and hydrolytic acidity at different development stages (DDS).

Abstract: Soil heavy metal contamination (SHMC) in greenbelt functional areas and their enrichment characteristics in 7 tree species were evaluated. The results showed that Cd contamination is the heaviest in all 4 heavy metals. The pollution level decreases in following order: Industrial Park Greenbelt (IPG), Urban Road Greenbelt (URG), Greenbelt along Both Sides of Songhua River (GBSSR), City Park Greenbelt (CPG), Agricultural Land (AL), Forest and Nursery Greenbelt (FNG). As for Zn, Cu and Cd contaminants, the bioconcentration factor (BCF) of Populus lasiocarpa is higher than other species, therefore, it should be selected as an important species to repair heavy metal polluted soil; the other tree species with relatively lower BCF can be selected as reserved tree species.

Abstract: This paper analyzes the bioavailability of soil heavy metal with morphology, geochemical facies, activity coefficient, migration coefficient, metastasis coefficient of soil heavy metal in the Puyu village, Huayin city. The research results show that: firstly, physiochemical properties of soil (include moisture content, available P, available K, total N, soil texture and so on) are key influencing factors for heavy metal activity, and correlation between total content and various morphology content of heavy metal too; secondly, antagonism and synergism are discovered among various heavy metal; thirdly, the correlation between the total content of heavy metal and physiochemical properties of soil such as PH value, moisture content, available P, available K, total N, soil texture is significant.

Abstract: With the increasing use of plastic film and the growth over time, the film residues are increasing in the field, accumulate on cultivated horizon and the surface layer and affect the soil physicochemical property. The paper, by potting experiment, shows the correlations between quantities of soil microbial populations, soil water, soil porosity and organism quantity under different treatments. And it may lay the foundation for the study of film residues influencing the soil quality.