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Preliminary study on assessment of nutrient transport in the Taihu Basin based on SWAT modeling

Science china Earth sciences 2006年第z1期49卷 135-145页

作者： LAI Geying, YU Ge & GUI Feng Nanjing institute of Geography & Limnology, Chinese academy of sciences, Nanjing 210008,{3. The Graduate School of the Chinese academy of sciences, Beijing 10003.,{3. Key Lab of Poyang Lake Ecological Environment and Resource Development, Jiangxi Normal University, Nanchang 3.0027,{3. 1. Nanjing institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China2. The Graduate School of the Chinese Academy of Sciences Beijing 100039 China3. Key Lab of Poyang Lake Ecological Environment and Resource Development Jiangxi Normal University Nanchang 330027 China

With the Taihu Basin as a study area, using the spatially distributed and mechanism-based SWAT model, preliminary simulations of nutrient transport in the Taihu Basin during the period of 1995～2002 has been carried out. The topography, soil, meteorology and land use with industrial point pollution discharge, the loss of agricultural fertilizers, urban sewerage, and livestock drainages were all considered in the boundary conditions of the simulations. The model was calibrated and validated against water quality monitoring data from 2001 to 2002. The results show that the annual total productions of nitrogen (TN) and phosphorus (TP) into Lake Taihu are 40000t and 2000t respectively. Nutrient from the Huxi Region is a major resource for Lake Taihu. The non-point source (surface source) pollution is the main form of catchment sources of nutrients into Lake Taihu,occupied TN 53. and TP 56% respectively. TN and TP nutrients from industrial point pollution discharge are 3.% and 16%, and sewerage in both forms of point source and non-point source are TN 3.% and TP 47%. Both the loss of agricultural fertilizers and livestock drainages from the catchment should be paid more attention as an important nutrient source. The results also show that SWAT is an effective model for the simulation of temporally and spatially nutrient changes and for the assessment of the trends in a catchment scale.

关键词： Taihu Basin, nutrients, catchment resource inputs, SWAT model, simulation.

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Micromorphological Analysis of soil Structure under No Tillage Management in the Black soil Zone of Northeast china

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Journal of Mountain Science 2009年第2期6卷 173-180页

作者： ZHOU Hu LI Baoguo LU Yizhong Department of soil and Water sciences China Agricultural University Beijing 100193 China

The structure of the ＂black soil＂ in Northeast china has been greatly deteriorated by long-term intensive conventional mouldboard plow tillage （CT） practices. In this study, micro- morphological observation and image analysis of soil thin sections were conducted to evaluate the impacts of 21 years （1986-2007） of no tillage （NT） on soil structure as compared to CT in an experiment near Gongzhuling City, Jilin Province. soil organic matter （SOM）, wet aggregate stability and saturated hydraulic conductivity （Ks） were also analyzed. Total SOM was not significantly affected by tillage systems, but fresher SOM was observed in the surface layer under NT. The aggregates under NT showed different hierarchies in the form of crumbs, and the mean weight diameter （MWD） of NT was significant higher than that of CT in the surface layer. Platy and blocky aggregates were frequently observed in the lower layers under CT practice. The compound pore structure with intertwined intra- and inter- aggregates pores under NT was well developed in a layer from 0-5 cm to 20-25 era. While under CT system, more inter-aggregate pores and fewer intra- aggregate pores were observed, and planes and channels were frequently found in the 20-25 cm layer, where maeroporosity decreased significantly and a plow pan was evident. The Ks values of NT weresignificantly lower at o-5 cm but significantly higher at 20-95 cm compared with CT, which showed the same trend with macroporosity. These results confirmed that long-term CT practice fragmented the tillage layer soil and compacted the lower layer soil and formed a plow pan. While long-term NT practice in the black soil region favored soil aggregation and a stable porous soil structure was formed, which are important to the water infiltration and prevent soil erosion.

关键词： No tillage soil structure soilmicromorphology image analysis black soil

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Effect of CO_2 Enrichment on the Growth and Nutrient Uptake of Tomato Seedlings

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Pedosphere 2007年第3期17卷 343-351页

作者： LI Juan ZHOU Jian-Min DUAN Zeng-Qiang DU Chang-Wen WANG Huo-Yan State Key Laboratory of soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of SciencesNanjing 210008 （China） Nanjing institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 （China）

Exposing tomato seedlings to elevated CO2 concentrations may have potentially profound impacts on the tomato yield and quality. A growth chamber experiment was designed to estimate how different nutrient concentrations influenced the effect of elevated CO2 on the growth and nutrient uptake of tomato seedlings. Tomato (Hezuo 906) was grown in pots placed in controlled growth chambers and was subjected to ambient or elevated CO2 (3.0 or 720μL L-1) and four nutrient solutions of different strengths (1/2-, 1/4-, 1/8-, and 1/16-strength Japan Yamazaki nutrient solutions) in a completely randomized design. The results indicated that some agricultural characteristics of the tomato seedlings such as the plant height, stem thickness, total dry and fresh weights of the leaves, stems and roots, the G value (G value = total plant dry weight/seedling age), and the seedling vigor index (seedling vigor index = stem thickness/(plant height×total plant dry weight) increased with the elevated CO2, and the increases were strongly dependent on the nutrient solution concentrations, being greater with higher nutrient solution concentrations. The elevated CO2 did not alter the ratio of root to shoot. The total N, P, K, and C absorbed from all the solutions except P in the 1/8- and 1/16-strength nutrient solutions increased in the elevated CO2 treatment. These results demonstrate that the nutrient demands of the tomato seedlings increased at elevated CO2 concentrations.

关键词： CO2 enrichment nutrient strength nutrient uptake tomato seedlings

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Identification and Practical Application of Silicate-dissolving Bacteria

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agricultural sciences in china 2002年第1期1卷 81-85页

作者： LIN Qi-mei, RAO Zheng-hua, SUN Yan-xing, YAO Jun and XING Li-jun( Department of soil and Water sciences , china {3. University, Beijing 100094 institute of Plant Nutrition and Resources , Beijing academy of {3. and Forestry sciences, Beijing 100081 ) Department of soil and Water sciences China Agricultural University Beijing 100094 institute of Plant Nutrition and Resources Beijing Academy of Agricultural and Forestry Sciences Beijing 100081

Slime-forming bacteria were isolated from soils, rock surface and earthworm intestine, and their effects on dissolving silicate minerals and tomato growth were examined. One of the bacteria, Bacillus mucilaginosus RGBc13. had particularly strong ability to form slime and dissolve silicates. RGBc13.could also colonize and develop in both non-rhizosphere and rhizosphere soil. Total number of slime-forming bacteria increased from 2.9 × 103.cfu·g-1and 8.4 × 103.cfu·g-1 to 9.6 × 106 cfu·g-1 and 6.0 × 107 cfu·g-1 in the non-rhizosphere and rhizosphere soils respectively. Potassium and phosphorus nutritional conditions in the rhizosphere were markedly improved through inoculation of this bacterium. Available K and P respectively increased from 25. 86 and 3. 63.g · kg-1 in the non-rhizosphere soil to 91. 23.and 5. 74mg · kg-1 in the rhizosphere soil. Tomato biomass increased by 125%, K and P uptakes were more than 150%, greater than the non-inoculation. Thus, there is a potential in applying RGBcl3.for improving plant K and P nutrition.

关键词： Silicate-dissolving bacteria Silicates Tomato

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Status and circulation characteristics of soil water in dryland field of southeast Shanxi Province

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Journal of Environmental sciences 1998年第4期10卷 27-34页

作者： Zhong Zhao zhan, Zhao Ju bao, Mei Xu rong institute of Agrometeorology, Chinese academy of agricultural {3., Beijing 100081, china

Based on the observed soil water data from experimental site located in southeast of Shanxi Province, the physical characteristics of soil water, crop effect on soil moisture, and the field water circulation pattern were studied by using the water balance method. The results suggested that soil water deficit often exists in fields of these areas. From May to June, the amount of water deficit in bare land rises to the maximum (23. 8 mm) and falls to the minimum (66 6 mm) from August to September. By comparison, because of crop transpiration, both soil water deficit and dry soil layer in cultivated land are 15 1—40 4 mm more and 20—70 mm deeper respectively than those of bare land. Crops mainly planted in these areas have a relatively weak utilization ability to soil water. Winter wheat has the highest utilization ability to soil water among the crops planted in these areas. The soil water utilization ability of winter wheat is 26 2%—3. 6% and winter wheat can use soil water that lies in soil layer below a depth of over 200 cm. Spring corn and millet can only consume soil water with the maximum ability of 13.4% and the deepest layer of 0—50 cm or 0—100cm, which shows that the soil water utilization ability of winter wheat is higher than that of spring crops. After crop is ripe, more than 41% of available soil water remains unused in field. So, increasing soil water storage and improving crop utilization ability to soil water by adopting efficient agrotechnique measures are the main ways for improving agricultural productivity in dry farming areas of Northern china.

关键词： soil water field water deficit crop utilization ability to soil water dry land southeast of Shanxi Province.

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研究节源高效持续农业是土肥科学肩负的历史重任

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吉林农业科学 1994年第2期19卷 47-50,60页

作者：孙宏德吉林省农科院土肥所

土壤是人类生存最基本的自然资源．农田的减少及土壤退化、沙化、盐碱化和沼泽化，严重威胁人类的生存．要使我国人均粮食在本世纪末达到４００公斤，就要走节源高效持续农业的道路，即在有限资源条件下，发挥其生产，注重生态系统，物... 详细信息

土壤是人类生存最基本的自然资源．农田的减少及土壤退化、沙化、盐碱化和沼泽化，严重威胁人类的生存．要使我国人均粮食在本世纪末达到４００公斤，就要走节源高效持续农业的道路，即在有限资源条件下，发挥其生产，注重生态系统，物质循环与各类资源的平衡与协调，增加农业产出，并保持其稳定增长．实践证明，土肥科学在研究节源高效持续农业方面，大有用武之地。应增加其投资强度，突出重点，加强综合配套研究。

关键词：持续农业土肥科学综合研究

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Fallout radionuclides (~7Be and ^(13.)Cs) in surface soils and lake sediments in west Yunnan and central guizhou, china

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Chinese Science Bulletin 1999年第S2期44卷 125-126页

作者： BAI Zhanguo~(1,2) and WAN Guojiang~1 1. State Key Laboratory of Environmental Geochemistry, institute of Geochemistry, Chinese academy of sciences, {3. 550002, china 2. State Key Laboratory of Plant Nutrition Research of Chinese Ministry of Agriculture institute of soil and fertilizer, Chinese academy of agricultural sciences, Beijing 100081, china

WEST Yunnan and central guizhou with variable altitudes and similar latitudes, located in the Yunnan-guizhou Plateau of the eastern slope uplifting Himalayas, were selected as study areas in this note. Thetwo areas consist mainly of carbonate rocks discontinuously covered by similar soil types with severe soiland water loss except Lugu Lake catchment. Climate of the study areas is subtropical monsoon, apparently influenced by mingled southeastern monsoon and southwestern monsoon with abundant *** study is to comparatively describe distribution and inventory of 7Be and 13.Cs in the sediments of Erhai Lake, Lugu Lake and Hongfeng Lake as well as in 28 surface soil profiles of their *** results have shown that: （i） In all the soil profiles, 7Be activities decrease exponentially with soil depth. 7Be apparent ac-

关键词： radionuclides soils sediments china.

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Nitrification-denitrifjcation Loss and N_2O Emission from Urea Applied to Crop-soil Systems in North china Plain

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agricultural sciences in china 2002年第2期1卷 184-188页

作者： DING Hong, CAI Gui-xin, WANG Yue-si and CHEN De-li( institute of soil and fertilizer , Fujian {3. of agricultural sciences , Fuzhou 3.0013.institute of soil Science, CAS, Nanjing 210008 LAPC , institute of Atmospheric Physics, CAS, Beijing 100029 institute of Food and Land Resources, Univ Melbourne , PV 3.52 , Australia )

Nitrogen losses are not only important for agriculture but environment as well. Field experiments were set up in summer corn field at Fengqiu Agro-Ecological Experimental Station of CAS in North china Plain. The soil was in maize-chao soil. Nitrification-denitrification losses and N2O emission were determined by acetylene-inhibition soil-core incubation method in the soils applied urea. The results showed that urea was fast hydrolyzed and became to nitrate. The soil with non urea released 0.3.kg N/ha N2O. However, the soil produced 2.91kg N/ha N2O, about 1.94% of the applied N, when the urea was spread on soil surface. N2O emission reduced to 2.50kg N/ha, about 1.67% of the applied N, when the urea was put in deep soil by digging a hole. The denitrification loss was 1.17kg N/ha in control soil. It increased to 3.00kg N/ ha and 2.09kg N/ha, which were 2.00% and 1.3.% of the used N, in the soils received urea on surface and sub-surface respectively. It was suggested that nitrification-denitrification was probably not a main way of fertilizer nitrogen loss in this region.

关键词： Corn Urea N2O emission

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Effect of Long-Term Application of Chemical fertilizers on Microbial Biomass and Functional Diversity of a Black soil

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Pedosphere 2008年第6期18卷 801-808页

作者： KONG Wei-Dong ZHU Yong-Guan FU Bo-Jie HAN Xiao-Zeng ZHANG Lei HE Ji-Zheng Research Center for Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 （China） Northeast institute of Geography and agricultural Ecology Chinese Academy of Sciences Harbin 150040 （China） institute of Microbiology Chinese Academy of Sciences Beijing 100080 （China）

An experiment with seven N, P, K-fertilizer treatments, i.e., control (no fertilizer), NP, NK, PK, NPK, NP2K, and NPK2 where P2 and K2 indicate double amounts of P and K fertilizers respectively, was conducted to examine the effect of long-term continuous application of chemical fertilizers on microbial biomass and functional diversity of a black soil (Udoll in the USDA soil Taxonomy) in Northeast china. The soil microbial biomass C ranged between 94 and 145 mg kg-1, with the NK treatment showing a lower biomass; the functional diversity of soil microbial community ranged from 4.13.to 4.25, with an increasing tendency from control to double-fertilizer treatments, and to triple-fertilizer treatments. The soil microbial biomass, and the microbial functional diversity and evenness did not show any significant differences among the different fertilizer treatments including control, suggesting that the long-term application of chemical fertilization would not result in significant changes in the microbial characteristics of the black soil.

关键词： Biolog black soil chemical fertilizer microbial biomass microbial functional diversity

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A STUDY ON FIELD WATER CIRCULATION PATTERN IN THE DRYLAND OF NORTHERN china

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Journal of Geographical sciences 1997年第4期7卷 36-43页

作者： Zhong Zhaozhan Zhao Jubao institute of Agrometeorology, Chinese academy of agricultural {3. Beijing 100081 People’s Republic of china

Based on the observed data of soil moisture from locating experiments from 1986 to 1990, the pattern of field water circulation in dryland of northern china, where the mean annual precipitation is 3.0 600 mm, is studied in this paper using the method of water balance. The results show that water satisfying ratio of spring seeding crops is 83.7 90.8 percent and that of winter wheat is about 70 percent in these areas; about 80 90 percent of water consumption of spring seeding crops and about 60 70 percent of water consumption of winter wheat comes from precipitation during the growing period, the rest comes from the soil water storage before the seeding period. But the available soil water is not used thoroughly, about 3. 70 percent of available soil water remains unused when the crops are harvested. At the fallow period, the amount of soil water lost by evaporation is very important, which takes up 57 68 percent of precipitation in winter wheat field and 73. 244 percent in field of spring seeding crops. Thus restraining soil evaporation, raising the storage ratio of natural precipitation and the soil water utilization efficiency of crops, strengthening the circulation ability of soil water by adopting efficient measures of agricultural techniques, are the main ways for exploiting and developing the potential productivity of natural precipitation in these areas.

关键词： crop field water soil evaporation crop water consumption field water circulation dryland

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