Advanced Materials Research Vols. 518-523

Abstract: Biological utilization of Saline soil is an effective way to improve land utilization and ecological environment. Oat is a unique crop of Inner Mongolia and has strong resistance to salt. This study setting five sowing depth of 3 cm, 5 cm, 7 cm, 9 cm and 11 cm on the morphological and physiological characteristics of two oat cultivars. The K⁺ /Na⁺ and selective absorption and migration, yield and nutrient quality, and soil salt content were measured from a field experiment. The highest yield of oat on saline land was obtained at sowing depth of 7 cm. The dry matter of stem and leaf accumulated more rapidly at 7 cm, membrane damage was less, leaf chlorophyll content was higher and kept higher photosynthetic capacity, K⁺ /Na⁺ and SK+, Na+ (migration) of stem and leaf were higher. So it showed stronger salinity adaptability and higher yield, and the yield was between 43.1% and 64.1% higher than conventional seed planting’s and it occupied between 37.2% and 42.7% of loam soil, and the crude fat content was higher. Sowing depth of 5 cm was the second choice, but sowing depth of 9 and 11 centimeter was not suitable to plant salt-enduring cultivar. The decrease sequence of oat yield and quality under salt stress was: grain yield > fresh yield > hay yield > crude fat > crude fiber. The grain yield and crude fat of salt-enduring cultivar Nei nong da you 1 were favorable for improving oat’s salinity adaptability and increasing the desalination in soil. The study can provide a theoretical basis to improve saline land utilization and high-yield cultivation of oat.

Abstract: Naiman County is the typical area in Korqin sand land. Chose cultivated land in Naiman County, this article carried on comparative analysis for soil physicochemical properties of cultivated land in different farming years. This included change characteristics of soil physicochemical properties with different farming years in different slope positions (windward slope, sloping top and leeward slope) of cultivated land and quantitative analysis between farming years and soil physicochemical properties. The results showed that: (1) there were different changes in soil texture in different slope positions of cultivated land in different farming years: at first 15 years, in the windward slope, the soil texture emerged good trend year by year, but after 30 years of farming, the soil texture get significantly worse. In the sloping top and leeward slope, the soil texture was changed for the better trend along with the increase of farming years. (2)There were different changes in soil nutrients in different slope positions of cultivated land during different farming years: in the windward slope, farmed from 3 years to 15 years, upward trend showed among the most nutrients and until 30 years, it obviously reduced and drop back to level of the 3 years; There was a rising trend in the leeward part of the nutrients; sloping top was between the middle and more indicators decline in nutrient content than that of increasing. (3) There was relationship between the farming years and soil physicochemical properties: the effects on soil texture was higher than the soil nutrients and correlation between different slope positions was different: in the windward slope, farming years correlated positively with sand and available P and a negative correlation was found between farming years and other indicators. In the sloping top, farming years correlated negatively with sand, total N, total K, alkaline N and available P, correlated positively with other indicators. In the leeward slope, farming years correlated negatively only with sand and total K, correlated positively with all of other indicators.

Abstract: The paper analyzed soil water evaporation variation of spring maize under film and straw mulching. The evaporation had the character of higher at early period and telophase, and lower in the middle. The soil water evaporation was significant different at different mulching material between before and after heading stage. It built an estimation method to cumulative soil water evaporation with spring maize height, and the model could product soil water evaporation early.

Abstract: Analyzed the relationships between rainfall and warp dam block sediment in Jinghe watershed in different years by regression analysis method base on the nearest material, the date shows: (1) The respond relation is changes between the warp dam retains sand and the rain in Jinghe river basin,80's is the biggest. The critical value is 1×107 t/a;the 1d and rain season and year rain critical value is bigger than 40mm,350mm,450mm. (2) The relationships between rainfall and warp dam block sediment in Jinghe watershed were different, it had two areas include high and low block sediment base the rainfall; the high value is 3.55 times than low value. The block sediment amount of warp dam will be calculated by the corresponding relation base the actual amount of rainfall flood in watershed. (3) The warp dam retains sand amount is about 0.016t/m3 in 1 m3 flood at 80's in Jinghe river basin, the warp dam retains sand is about 0.0045t/m3 in 1 m3 flood at other years in Jinghe river basin, was growing to 0.021t/m3 near period. (4) They have the line relation between warp dams reduce sediment and soil erosion in different spatial scale river basin in middle of yellow river. The rate of reduce sediment to retain sand increase with the area decrease.

Abstract: The Huajiang Demonstration Area, which is a representative karst area with typical rocky desertification landscape in Guizhou was chosen as the study area. Based on the 5m resolution Spot 5 remote sensing images, the topographic maps (1:10 000) and the land use map etc, the rocky desertification of the area was interpreted. We took quantitative analysis through introducing two concepts: the rocky desertification occurrence among land use/land cover and the land use/ cover structure value of rocky desertification. The data showed that(1) the proportion of highly steep slopes in the study area is one of the reasons leading to large area of rocky desertification; (2)The rocky desertification occurrence among different land use/cover is different, and the land use/ cover type structure among rocky desertification is also different among all grades of desertification; (3)Rocky desertification intensity in different land use/cover can’t be measured in means of rocky desertification occurrence, high rocky desertification occurrence may be in a low-intensity state, and vice versa. (4)It is suggested that land use conditions, rocky desertification grades, and terrain of the land should be fully considered in the process of designing and matching rocky desertification control measures.

Abstract: The baseline values of Copper (Cu) and Lead(Pb) in four subtypes of soil in Hohhot, Inner Mongolia in China were proposed by testing the Cu and Pb contents in surface soils over an area of 4713km2．The soil subtypes were distinguished by GIS (Geographic Information System) and the 928 sample locations were roughly uniformly distributed using portable GPS (Global Positioning System).The proposed baseline values of Cu and Pb were derived from the experimental results of ICP-MS analyses and then were calculated by probability density function. The results illustrate that the baseline value of Cu in the Fluvo—aquic Soil was the highest(18.83 mg kg-1 ),and that Pb in Diluvial Alluvial Topsoil was the highest (17.50 mg kg-1),which are far lower than the corresponding Class One thresholds in Environmental Quality Standard for Soils in China (GB15618-1995) (EQSSC).This experience gained in this work further suggests that baseline values should be proposed in other areas in the world.

Abstract: A monitoring system was implemented to monitor the hydrodynamic and deformation response of a preexisting landslide in the Three Gorges Reservoir area. The monitoring results indicate that the deformation is mainly caused by reservoir impounding and is mainly composed of the deformation of the slip band. The effect of reservoir level fluctuation on landslide stability mainly depend on two aspects, one is the change of shear stress and shear strength on the slip surface due to the change of slide body weight and pore water pressure, the other is seepage pressure.

Abstract: Aiming at reducing agricultural pollution caused by plastic film, the effects of re-used plastic film mulching on soil moisture, temperatures and soil erosion during fallow period of cropland were studied, the study also investigated plastic film residue and sunflower’s yield, which compared with new plastic film mulching and bare field in Hetao region. The results showed that, compared with bare field, (1) the average soil moisture in 0~100 cm of re-used film mulching increased 2.1%, the water storage capacity in 0~100 cm and 0~20 cm increased 24.8~33.0mm and 14.9~15.5mm separately. (2) The soil average temperature significantly increased 3.1~2.8°C, especially soil temperature in 5 cm and 10 cm increased 1.7~4.6°C and 2.8~4.1°C separately (p < 0.05). (3) The amount of soil erosion significantly reduced by 68.77%. (4) Compared with new plastic film mulching, the residual plastic film of re-used film mulching cropland significantly reduced 50%, and the film use efficiency increased 1 time. (5) In addition, compared with bare field, sunflower yield of re-used film mulching was significantly increased 11.4% in 2010 and 16.8% in 2011 (p < 0.01), and compared to the new film treatment, the yield decreased 3.3% in 2010 and 2.6% in 2011 (p < 0.05). So re-used plastic film mulching can improve the ecological environment of cropland in fallow period, reduce the film pollution and increase grain yield.

Abstract: In recent years, a variety of soil amendments came out and achieved certain results in the modification of desertification soil. However, most soil amendments belong to chemical product. They’re cost and produce secondary pollution easily. In order to further study on the measures to improve degeneration soil, make full use of renewable resources, and minimize secondary pollution, corn straw, bentonite and PAM were used simultaneously in the pot experiment to explore their synergic effect on the structure of sandy soil. In this test, corn straw is selected as the research objects. Different amounts of straw modified materials are applied in the pot experiment. Physical properties such as pH, bulk density, and aggregates were analyzed at 10 days, 30 days, 60 days and 90 days. Results showed that under the condition of different additions and doses of straw modified material, with the increase of PAM, the straw modified material did not have significant influence on pH value of sandy soils. Bulk density of the sandy soil decreased under the effect of the straw modified material. The higher the doses, or the more the content of PAM (but still<2%), the more apparently the bulk density decreased. With the increase of time, bulk density of the soil first increased and then decreased, reaching minimum at 60 days. The content of 1~5 mm aggregate increased obviously at 90 days with the addition of modified material, which was 2.12 times of control value. With the increase of content of PAM (<2%), the content of 1~5 mm aggregate increased gradually. When the content of PAM continued to increase (reaching 3%), the content of 1~5 mm aggregate decreased instead. Effect of straw modified material on sandy soil was optimum under the condition of corn straw, bentonite (albany grease, 200 item) and PAM (anionic poluacrylamides, 1.0×107 daltons, and solution 30%) 900:100:20, 10g/5kg for 60 days of pot experiment.

Abstract: There was less vegetation on the bare slope of mountainous area due to sterile soil in Beijing than other places. Soil and water loss was so serious that vegetation restoration became important one of ecological engineering. So experiment was executed to plant eco-grass on the bare slope in Miyun reservoir watershed and Guanting reservoir watershed, and study effect of eco-grass on soil and water conservation. The results indicated that vegetation restored quickly on the bare slope of mountainous area after eco-grass planted for a year, roughness length on the earth’s surface increased, and soil and water loss reduced clearly. Meanwhile soil bulk density reduced, and soil infiltration and available nutrients increased obviously. So soil physical and chemical properties improved batter in a short time than no eco-grass.