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21.
To investigate the impacts of the invasion by bamboo on fluxes of nutrients and pollutants, the nutrient/pollutant fluxes and canopy interactions, including neutralization of acidity, leaching and uptake of nitrogen (N), were characterized in conjunction with rainfall partitioning in a Moso‐bamboo (Phyllostachys pubescens) forest. Measurements of precipitation volume, pH, major ions, and silicate (SiO2) in rainfall, throughfall and stemflow were collected weekly in a Moso‐bamboo forest located in Munakata City, Western Japan for 1 year. Results showed that rainfall partitioning into stemflow was larger than that for other types of forest, which may be due to the properties of Moso‐bamboo forest structure, such as a straight and smooth culm. Inorganic N (NO3 + NH4+) and S (SO42−) fluxes of throughfall and stemflow were approximately 1·6 and 1·3 times higher than that of rainfall, respectively. Contribution of stemflow flux to inorganic N and S fluxes to the forest floor was high. This could be due to lower uptake of inorganic N through culm and a higher rainfall partitioning into stemflow than that for other types of forest. The Moso‐bamboo canopy neutralized rainfall acidity, reducing the fluxes of potentially acidifying compounds via throughfall and stemflow. Canopy leaching of K+ was distinctly higher than that of Mg2+ and Ca2+ and could be related to the high mobility of K+ in plant tissues. Cl and SiO2 were readily leached as for K+. The impact of the invasion by bamboo on nutrient cycling was discussed. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
22.
We investigated the spatial and seasonal variations in throughfall (Tf) in relation to spatial and seasonal variations in canopy structure and gross rainfall (Rf) and assessed the impacts of the variations in Tf on stand‐scale Tf estimates. We observed the canopy structure expressed as the leaf area index (LAI) once a month and Tf once a week in 25 grids placed in a Moso bamboo (Phyllostachys pubescens) forest for 1 year. The mean LAI and spatial variation in LAI did have some seasonal variations. The spatial variations in Tf reduced with increasing Rf, and the relationship between the spatial variation and the Rf held throughout the year. These results indicate that the seasonal change in LAI had little impact on spatial variations in Tf, and that Rf is a critical factor determining the spatial variations in Tf at the study site. We evaluated potential errors in stand‐scale Tf estimates on the basis of measured Tf data using Monte Carlo sampling. The results showed that the error decreases greatly with increasing sample size when the sample size was less than ~8, whereas it was near stable when the sample size was 8 or more, regardless of Rf. A sample size of eight results in less than 10% error for Tf estimates based on Student's t‐value analysis and would be satisfactory for interception loss estimates when considering errors included in Rf data. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
23.
竹醋对生活污水好氧处理的强化作用初步研究   总被引:1,自引:0,他引:1  
采用在生活污水好氧处理之前投加外源物质的方法 ,研究了竹醋 (Bamboo Vinegar,BV)及其主要有机成分 (乙酸 )对污水好氧处理效果的强化作用。结果表明 :1当 VBV/ V污水 的比值达到1 / 1 0 6时 ,BV对污水 CODcr的去除有极显著的强化作用 :CODcr去除率比不加竹醋的对照组提高1 0 %。但是 ,BV对污水中 NH+ 4 - N,T- P的去除率没有影响。 2乙酸单独使用亦可显著提高污水CODcr去除率 ,当 V乙酸 / V污水 为 1 / 1 0 7时 ,强化效果最好 ,CODcr去除率提高 1 3%。由于乙酸具有与BV相似的作用特点 ,所以认为 BV对污水处理效果的强化作用来自其中的乙酸。为了将 BV应用于污水处理中 ,需要进一步研究确定 BV对活性污泥法、生物膜法处理污水的强化效果  相似文献   
24.
The cold-water bamboo coral, dwelling in the depths of global seas, is characterized by the “bamboo-like” skeletal structure of alternating calcite internodes and gorgonin nodes, and has “tree-ring-like” concentric growth rings transversally. Paleoceanograhic reconstructions using bamboo coals would fill the geographic and temporal gaps of traditional means. In this work, the inorganic geochemical proxy methods for bamboo coral are introduced, including Mg/Ca for ambient temperature, Ba/Ca for seawater nutrient content, and δ11B for seawater pH. Also, the potential influences of vital effect on the proxy reconstructions are briefly discussed. With the recent findings of deep-sea bamboo coral forests in the western Pacific region, a new territory of bamboo coral paleoceanography is opened for the scientists from the nearby countries.  相似文献   
25.
试论河南竹产业的发展   总被引:1,自引:0,他引:1  
文章在分析河南省竹产业发展的历史渊源、现状和存在问题的基础上,论述了竹产业发展的重要性。提出河南竹产业发展的对策是:统一认识、转变观念;查清资源、统一规划;依靠科技人才、走科技兴之路;抓好基地建设、综合治理环境等。  相似文献   
26.
从我国边坡防护工程结构工作效力的角度进行检核和反思,例如场地需求匹配度、工程结构稳定性和耐久性、管养维护,等等,总结了落石防护工程的发展内在需求,进而在前人工作的基础上凝炼总结并发展出一种以被动网、落石挡墙等工程防护为临时措施、以散生竹等生态植被防护为永久措施的永临结合防护结构,文章将其命名为混成型生态防护系统。继而,将生态防护作为基本的指导思想,以某景区公路建设为例,通过对防护需求的分析研判,以及建设区域符合防护需求的生态植被的调研,将散生竹作为生态植被用作实践方案进行应用验证防护系统的可行性。文章进行了混成型生态防护系统的防护思路框架的初步探索,也力图通过对散生竹等植被研究资料的再利用、再研究,最后展望了该系统的发展、完善思路和方向。抛砖引玉,以供参考。  相似文献   
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