杉木与楠木凋落叶混合分解及其P、K动态     

江淼华  程徐冰  杨建忠  郭剑芬 《福建地理》2012,(3):14-19

将杉木、楠木凋落叶及以二者不同比例混合的凋落叶置于果园林内进行分解和P、K动态的研究,结果表明：杉木和楠木凋落叶混合处理的分解速率均大于单独分解的纯杉木和纯楠木凋落叶.各凋落叶分解过程中,P浓度略有增加,而K浓度基本呈下降趋势.纯杉木凋落叶分解过程中P、K残留率均比纯楠木叶的低.杉楠混合分解的P、K释放率基本上大于单独的纯楠木叶.杉木与楠木凋落叶混合分解对其P和K的释放有一定的促进作用.  相似文献   

ANALYSIS OF THE WESTWARD EXTENSION OFWESTERN PACIFIC SUBTROPICAL HIGH DURING A HEAVY RAIN PERIOD OVERSOUTHERN CHINA IN JUNE 2005     

司东  徐海明  温敏  何金海 《热带气象学报(英文版)》2008,14(2):93-96

The NCEP/NCAR II daily mean reanalysis data and observed precipitation data are employed to investigate the westward extension of the western Pacific subtropical high (WPSH) during the heavy rain period over the southern China in June 2005. Results show that there may exist a relationship between the east-west shift of the WPSH and the process of a southern China heavy rain. The analysis indicates that the vertical motion in the WPSH area is mainly caused by the latent heat release of monsoon rain belts on its northern and southern sides. The vertical motion could cause the accumulation of air mass in the center and west of the WPSH, which leads to its strengthening. The appearance of the northern and southern monsoon rain belts could not only enhance the WPSH by strengthening the descending draft, but also excite the development of positive vorticity and restrict the WPSH’s movement in the north–south direction. Moreover, the Indian monsoon rainfall to the west of the WPSH may excite the development of anticyclonic vorticity on its eastern side, which leads to the westward extension of the WPSH.  相似文献   

高原东移对流系统对西南低涡形成的作用   总被引：2，自引：0，他引：2       下载免费PDF全文

FU Shen-Ming  SUN Jian-Hu  ZHAO Si-Xiong  LI Wan-Li 《大气和海洋科学快报》2010,3(1):51-57

Based on the temperature of the black body (TBB), station observed and NCEP reanalysis data, the impacts of the eastward propagation of convective cloud systems over the Tibetan Plateau on the southwest vortex (SWV) formation that occurred at 1800 UTC on 29 June 2003 are analyzed by using the Zwack-Okossi (Z-O) equation to diagnose the thermal and dynamic processes. It is found that, in summer, severe convective activities often occur over the Tibetan Plateau due to the abundant supply of moisture. The convective cloud near the east edge of the plateau could move eastward with a short-wave trough in the westerly. The divergent center that is induced by latent heat release, which is associated with severe convective activities, moves out with the convective cloud and contributes to the low level decompression which is favorable for the formation of plateau edge cyclogenesis (PEC). The Z-O equation indicates that, in this case, the latent heat release and convergence are the two most important factors for SWV formation, which amounts to about 42% and 15% of the term TOTAL, respectively. It is implied that the thermal process effect was more important than the dynamic process during SWV formation.  相似文献   

http://www.sciencedirect.com/science/article/pii/S1674987110000095   总被引：1，自引：0，他引：1  

Xiluo Hao  Kwunlun Leung  Rucheng Wang  Weidong Sun  Yiliang Li 《地学前缘(英文版)》2010,1(1):81-89

<正>Bauxite deposits are studied because of their economic value and because they play an important role in the study of paleoclimate and paleogeography of continents.They provide a rare record of the weathering and evolution of continental surfaces.Geomicrobiological analysis makes it possible to verify that microorganisms have played a critical role during the formation of bauxite with the possibility already intimated in previous studies.Ambient temperature,abundance of water,organic carbon and bioavailable iron and other metal substrates provide a suitable environment for microbes to inhabit.Thio-bacillus, Leptospirilum,Thermophilic bacteria and Heterotrophs have been shown to be able to oxidize ferrous iron and to reduce sulfate-generating sulfuric acid,which can accelerate the weathering of alumi-nosilicates and precipitation of iron oxyhydroxides.Microorganisms referred to the genus Bacillus can mediate the release of alkaline metals.Although the dissimilatory iron-reducing and sulfate-reducing bacteria in bauxites have not yet been identified,some recorded authigenic carbonates and "bacteriopyrites" that appear to be unique in morphology and grain size might record microbial activity.Typical bauxite minerals such as gibbsite,kaolinite,covellite,galena,pyrite,zircon,calcium plagioclase,orthoclase, and albite have been investigated as part of an analysis of microbial mediation.The paleoecology of such bauxitic microorganisms inhabiting continental(sub) surfaces,revealed through geomicrobiolo-gical analysis,will add a further dimension to paleoclimatic and paleoenvironmental studies.  相似文献   

Optimized reservoir operation to balance human and riverine ecosystem needs: model development,and a case study for the Tanghe reservoir,Tang river basin,China     

Xinan Yin  Zhifeng Yang  Wei Yang  Yanwei Zhao  He Chen 《水文研究》2010,24(4):461-471

Reservoirs impose many negative impacts on riverine ecosystems. To balance human and ecosystem needs, we propose a reservoir operation method that combines reservoir operating rule curves with the regulated minimum water release policy to meet the environmental flow requirements of riverine ecosystems. Based on the relative positions of the reservoir and the water intakes, we consider three scenarios: water used for human needs (including industrial, domestic and agricultural) is directly withdrawn from (1) the reservoir; (2) both reservoirs and downstream river channels and (3) downstream river. The proposed method offers two advantages over traditional methods: First, it can be applied to finding the optimal reservoir operating rule curves with the consideration of environmental flow requirement, which is beneficial to the sustainable water uses. Second, it avoids a problem with traditional approaches, which prescribe the minimum environmental flow requirements as the regulated minimum environmental flow releases from reservoirs, implicitly giving lower priority to the riverine ecosystem. Our method instead determines the optimal regulated minimum releases of water to sustain environmental flows while more effectively balancing human and ecosystem needs. To demonstrate practical use of the model, we present a case study for operation of the Tanghe reservoir in China's Tang river basin for the three above‐mentioned scenarios. The results demonstrate that this approach will help the reservoir's managers satisfy both human and environmental requirements. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

基于GIS的重点污染源管理信息查询与分布系统设计的实现   总被引：3，自引：0，他引：3  

张卫东  谢庆胜 《安徽地质》2001,11(4):261-264

系统应用地理信息系统(GIS)技术、数据库技术、多媒体技术、Internet／Intranet技术，实现对污染源空间信息和非空间信息的综舍管理。直现地表现各类污染源的分布特点、总量特征及其排放污染物的动态变化。并通过网络实现污染源信息网上发布。本文概要介绍了系统的组成、结构、数据库以及系统的功能及其实现。  相似文献   

卸荷工程岩体非线性模型的研究与应用     

孙英学 《江苏地质》2001,25(1):41-43

卸荷工程岩体与传统的加载岩体的力学条件有着本质的区别，其非线性特征更为明显，卸荷工程岩体的研究是一个崭新的领域，对卸荷岩体的工程地质特征、力学参数的确定、本构关系及卸荷岩体释放荷载的计算方面进行了初步的探讨。  相似文献   

Remarks on the accelerated moment release model: problems of model formulation, simulation and estimation   总被引：3，自引：0，他引：3  

David Vere&#;Jones  Russell Robinson  Wenzheng Yang 《Geophysical Journal International》2001,144(3):517-531

  相似文献   

钻头模具一次成型新材料的研究          下载免费PDF全文

郭文斌  白洁 《探矿工程》1995,(3):25-29

介绍钻头模具的新型材料－成型砂的特点，选择，配制，成型工艺，产品的制造及测试等。  相似文献   

Promoting　effects　of　1975　Haicheng　foreshocks　on　theoccurrence　of　the　mainshock     

李兴才 《地震学报(英文版)》1994,7(3):409-414

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