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侵蚀性降雨标准研究

水土保持学报 2000年第4期14卷 6-11页

作者：谢云刘宝元章文波北京师范大学环境演变与自然灾害教育部重点实验室北京100875

建立侵蚀性降雨标准 ,是为了区分发生和不发生侵蚀的降雨事件 ,从而大大减少计算降雨侵蚀力的工作量 ,并提高土壤侵蚀预报精度。利用陕西团山沟小流域及所在 3个小区 1961- 1969年的降雨过程资料 ,以漏选和多选降雨事件的降雨侵蚀力相... 详细信息

建立侵蚀性降雨标准 ,是为了区分发生和不发生侵蚀的降雨事件 ,从而大大减少计算降雨侵蚀力的工作量 ,并提高土壤侵蚀预报精度。利用陕西团山沟小流域及所在 3个小区 1961- 1969年的降雨过程资料 ,以漏选和多选降雨事件的降雨侵蚀力相等为原则 ,分别建立了黄土高原坡面侵蚀的侵蚀性降雨雨量标准 12 mm,平均雨强标准 0 .0 4 mm/min,最大 30 min雨强标准 0 .2 5mm/min。其中时段雨强标准筛选精度最高 ,可剔除 88%以上的降雨事件 ,只有5.3%的错选度。其次是平均雨强标准 ,雨量标准筛选精度最差。漏选降雨侵蚀力之和与多选降雨侵蚀力之和相抵为原则建立的侵蚀性降雨标准 ,对于计算降雨侵蚀力 ,提高土壤侵蚀预报精度 ,具有重要意义。

关键词：侵蚀性降雨标准降雨侵蚀力土壤侵蚀预报降雨强度

AGRICULTURAL HAIL DAMAGE AND ITS SEASONAL REGIONALIZATION IN china

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natural disaster Reduction in china 2003年第3期 24-27页

作者： Wang Ying1, Wang Jingai2, Wu Wenbin3 and Li Wenhang2 (1. Institute of Resource Sciences, beijing normal university, key laboratory of Environment change and natural disaster,ministry of education of china, beijing 100875 2.Department of Resources and environmental Sciences, beijing normal university, beijing 100875, china 3.Institute of natural Resources and Regional Planning, Chinese Academy of Agriculture Sciences, beijing 100087, china)

According to the hail damage database of china, both the damage affected area and seriously affected area show a descending trend, while the ratio of the latter to the former ascends on the contrary. The seasonal variation of hail damage is quite obvious, spring and summer are the main periods of time of hail shooting throughout the whole country, and the frequency of hail shooting during April～September accounts for 92.3% of whole year. The distribution zone of hail shooting and seriously hail damage-affected area have an evident difference, and the center of hail damage is located in the Huang-Huai-Hai Plain and hilly regions on the south of the Yangtze River. Based on the map of county-level seasonal hail damage and the map of agriculture comprehensive regional planning, this paper designs the seasonal regionalization of hail damage by the methods of “from top to bottom” and “from bottom to top”, and china is divided into 5 types of hail damage zones with 16 second regions and 28 thrid regions. The 5 types are: summer type (I); later-spring/early-summer and summer type (II); later-spring and early-summer and double peak type (III); spring type (IV); summer and double peak type (V).

关键词： hail damage agriculture seasonal regionalization china

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东北漫岗黑土区春季冻融期浅沟侵蚀

山地学报 2006年第3期24卷 306-311页

作者：张永光伍永秋刘宝元北京师范大学沙漠与沙区资源研究所北京师范大学环境演变与自然灾害教育部重点实验室北京师范大学地理与遥感科学学院

浅沟侵蚀是东北漫岗黑土区农耕地上常见的水蚀类型,往往对坡耕地造成严重的破坏。2005年春季,通过对两个小流域浅沟侵蚀的调查测量,发现该区浅沟侵蚀相当严重,两流域分别形成浅沟14条、16条,浅沟总长度分别达3 269 m、2 146 m,浅沟密度... 详细信息

浅沟侵蚀是东北漫岗黑土区农耕地上常见的水蚀类型,往往对坡耕地造成严重的破坏。2005年春季,通过对两个小流域浅沟侵蚀的调查测量,发现该区浅沟侵蚀相当严重,两流域分别形成浅沟14条、16条,浅沟总长度分别达3 269 m、2 146 m,浅沟密度分别为908 m/km2、766 m/km2,侵蚀深度分别为0.17 mm、0.16 mm,侵蚀模数分别达181.8 t/km2、173.6 t/km2。2005年春季两流域浅沟侵蚀期的径流深分别是6.8 mm、7.7 mm。分析表明,研究区在春季表层土壤解冻、地表裸露和存在季节性冻土层的条件下,春季融雪及强降水易造成强烈的浅沟侵蚀。在分布上,浅沟一般位于坡面的中下部,而且多发育在瓦背状坡面的集流水路上。另外,耕作措施对浅沟的形成和发展也有重要影响。

关键词：黑土区强降水冻融浅沟侵蚀

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国内外降雨侵蚀力简易计算方法的比较

水土保持学报 2001年第3期15卷 31-34页

作者：伍育鹏谢云章文波北京师范大学资源与环境科学系环境演变与自然灾害教育部重点实验室北京100875

降雨是引起土壤侵蚀的主要动力 ,用 EI30 指标度量。计算 EI30 时 ,需要降雨过程资料 ,而且计算繁琐和费时 ,为此 ,很多学者采用常规降雨资料计算降雨侵蚀力的简易算法。它们往往利用区域资料经验拟合求得 ,如要推广使用 ,需要进行验证... 详细信息

降雨是引起土壤侵蚀的主要动力 ,用 EI30 指标度量。计算 EI30 时 ,需要降雨过程资料 ,而且计算繁琐和费时 ,为此 ,很多学者采用常规降雨资料计算降雨侵蚀力的简易算法。它们往往利用区域资料经验拟合求得 ,如要推广使用 ,需要进行验证。利用我国 10个气象站降雨过程和常规降雨资料 ,通过对国内外 9种比较有代表性的多年平均年降雨侵蚀力简易计算方法的比较 ,建议采用年雨量的指数函数形式作为估算我国多年平均年降雨侵蚀力的简易计算方法。为保证计算结果的区域稳定性 ,应分不同区域进行拟合。

关键词：土壤侵蚀降雨侵蚀力 EI30 简易计算方法

Climatic changes documented by stable isotopes of sedimentary carbonate in Lake Sugan, northeastern Tibetan Plateau of china,since 2 kaBP

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Science Bulletin 2005年第17期 116-125页

作者： QIANG Mingrui1,2, CHEN Fahu2, ZHANG Jiawu2, GAO Shangyu1 & ZHOU Aifeng2 1. china Center of Desert Research at beijing normal university and key laboratory of environmental changes and natural disaster, ministry of education of china, beijing normal university, beijing 100875, china 2. Center for Arid Environment and Paleoclimate Research (CAEP), National laboratory of Western china’s environmental System, Min-istry of education of china, Lanzhou university, Lanzhou 730000, china

Lake Sugan at the northern edge of the Qaidam Basin was selected as the research object. The temporal se-quence of sedimentary cores retrieved from Lake Sugan since 2 kaBP was reconstructed using the 210Pb, AMS 14C and conventional 14C dating methods. Carbon and oxygen iso-topes of carbonate in the fine-grained lake sediments were analysed. Combined with the changes of δ 18O values of sur-face water and air temperature observation data in the study area, it might be thought that the δ 18O value of the carbon-ate indicates effective moisture, and the changes in δ 13C val-ues are related to annual freeze-up duration of the lake and indirectly indicate air temperature changes in winter half year. From the above, the sequence of climatic changes in the region since 2 kaBP was established. The climatic changes experienced five stages: Warm-dry climate during 0-190 AD; cold-dry climate during 190-580 AD; warm-dry cli-mate during 580-1200 AD (MWP); cold-wet climate during 1200-1880 AD (LIA); cold-dry climate during 1880-1950 AD; and climate warming since 1950s. The air temperature changes in winter half year reflected by carbon isotope since 2 kaBP are in good agreement with the historical literature records and other geologic records, which shows that the climate changes recorded by the stable isotopes from Lake Sugan since 2 kaBP are of universal significance.

关键词： Lake Sugan carbonate stable isotope climatic changes.

Soil Moisture and Oilseed Rape Yields as Affected by Configuration of Ridge-furrow Tillage in the Semiarid Region of china

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Soil Moisture and Oilseed Rape Yields as Affected by Configu...

A preliminary knowledge-driven prediction model of snail distribution in the Poyang Lake region

2007中国科协年会

作者： Liu Muxing~1 Wang Jingai~(2,4) Liu Lianyou~(2,3) Yan Ping~(2,3) 1.College of City and Environment,Huazhong normal university,Wuhan 430079,china 2.key laboratory of environmental change and natural disaster of ministry of education,beijing normal university,beijing 100875.china 3.College of Resources Science & Technology,beijing normal university,beijing 100875.china 4.College of Geography and Remote Sensing Sciences,beijing normal university,beijing 100875.china

Ridge-furrow tillage is a kind of conservation tillage widely used for soil and water conservation in agriculture,with crop planted in ridge or *** previous researches mostly focus on the effects of ridge-furrow tillage with crop planted in ridges on crop growth and soil water content,Influence of ridge-forrow tillage with crop planted in furrows are not well documented,despite it is helpful to crop growth in arid and semiarid *** purpose of this study was evaluating the effect of ridge-furrow tillage with different surface configurations and crop planted in furrow,on the efficiency for rainwater harvesting and crop production,to determine the optimal surface configuration of ridge-furrow *** parameters of ridge heights (H) and ridge-furrow ratios (R,ratio between H and furrow width,W) were defined to determine the configuration of ridge-furrow *** field experiments,seasonal dynamic variation of volumetric soil water content, aboveground biomass and yields of oilseed rape (Brassica napus L.) were *** treatments included four kinds of ridge-furrow tillage with oilseed rape planted in furrow and one kind of conventional field tillage (CT) for *** results indicate that relative to CT,ridge-furrow tillage increased volumetric soil water content of the plow layer (0-30 cm) by 4.2%-12.1%,decreased its fluctuation in the growing season of oilseed *** the soil profile under ridge-furrow tillage,soil layer with the highest soil water content appeared in the depth of 0-30 cm,which helped oilseed rape absorb water by *** aboveground biomass,pods per plant and 1000-seed weigh under ridge-furrow tillage were larger than that under *** field comparison of oilseed rape yields under four forrow planting practices with 15,25 cm H and 1/6,1/12,1/24 R,we found the practice with 25 cm H and 1/24 R increased the efficiency of water harvesting,the growth and yield of the oilseed rape more ***,we recommend furr

关键词： ridge-furrow tillage furrow planting volumetric soil water content aboveground biomass theoretical yield rainfed agriculture

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Chinese Science Bulletin 2008年第1期53卷 115-123页

作者： ZHAO An1,2,3 & BAO ShuMing1 1 The key Lab of Poyang Lake Ecological Environment and Resource Development, Jiangxi normal university, Nanchang 330022, china 2 Institute of Geographic Sciences and Resources Research, Chinese Academy of Sciences, beijing 100101, china 3 School of Geography and environmental Sciences, Jiangxi normal university, Nanchang 330022, china The key Lab of Poyang Lake Ecological Environment and Resource Development Jiangxi Normal University Nanchang China Institute of Geographic Sciences and Resources Research Chinese Academy of Sciences Beijing China School of Geography and environmental Sciences Jiangxi Normal University Nanchang China

Present monitoring and prediction of schistosomiasis’s intermediate parasite, snail, are based on re-mote sensing image’s spectral signatures, and the calculation result is in fact an incom-plete-constraints solution. TM image of the Poyang Lake region on October 31, 2005 was combined with GIS thematic data (DEM, boundary of the Poyang Lake, vegetation, soil and land use) to make a prediction on snail spatial distribution in the region by remote sensing, geo-informatics and knowl-edge-driven modeling according to mechanism of snail occurrence. Result shows that with change of overall fuzzy membership of snail occurrence from high to low, snail occurrence of the snail samples of validation group goes up to 81% within 10% high fuzzy membership range, denoting high efficiency of the model in predicting snail occurrence.

关键词：鄱阳湖区域蜗牛分布模糊分类血吸虫病

Contribution of Root and Microbial Respiration to Soil CO_2 Efflux and Their environmental Controls in a Humid Temperate Grassland of Japan

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Pedosphere 2009年第1期19卷 31-39页

作者： WANG Wei FENG Jiang T. OIKAWA Department of Ecology College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of the Ministry of Education Peking University Beijing 100871 （China） School of Urban and environmental Sciences Northeast Normal University Changchun 130024 （China） Institute of Biological Sciences University of Tsukuba Tsukuba Ibaraki 305-8572 （Japan）

Soil CO2 efflux, root mass, and root production were investigated in a humid temperate grassland of Japan over a growing season （Apr. to Sep.） of 2005 to reveal seasonal changes of soil CO2 efflux, to separate the respective contributions of root and microbial respiration to the total soil CO2 efttux, and to determine the environmental factors that control soil respiration. Minimal microbial respiration rate was estimated based on the linear regression equations between soil CO2 effiux and root mass at different experimental sites. Soil CO2 efflux, ranging from 4.99 to 16.29 μmol CO2 m^-2 s^-1, depended on the seasonal changes in soil temperature. The root mass at 0-10 cm soil depth was 0.82 and 1.27 kg m^-2 in Apr. and Sep., respectively. The root mass at 0-10 cm soil depth comprised 60% of the total root mass at 0-50 cm soil depth. The root productivity at 0-30 cm depth varied from 8 to 180 g m^-2 month^-1. Microbial and root respiration rates ranged from 1.35 to 5.51 and 2.72 to 12.06μmol CO2 m^-2 s^-1, respectively. The contribution of root respiration to the total soil CO2 efflux averaged 53%, ranging from 33% to 72%. The microbial respiration rate was exponentially related to soil temperature at 10 cm depth （R^2 = 0.9400, P = 0.002, n = 6）, and the root respiration rate was linearly related to the root production at 0-30 cm depth （R2 = 0.6561, P = 0.042, n = 6）.

关键词： grasslands microbial respiration root production root respiration

A regression analysis of the effect of natural disaster on agriculture

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A regression analysis of the effect of natural disaster on a...