植物加固路堤边坡浅层土体分析及工程应用   总被引：1，自引：0，他引：1  

夏琼  杨有海  孙彦英 《岩土工程技术》2005,19(5):245-248

在总结植物加固黄土路堤边坡浅层土体的机理之后,结合宝中铁路实际工程,对紫穗槐和柠条两种植物的加固效果进行了详细的分析。  相似文献   

Environmental significance of C/C and O/O ratios of modern land-snail shells from the southern great plains of North America     

Meena Balakrishnan  James L. Theler  Don G. Wyckoff 《Quaternary Research》2005,63(1):15-30

¹³C/¹²C and ¹⁸O/¹⁶O ratios of aragonite shells of modern land snails from the southern Great Plains of North America were measured for samples from twelve localities in a narrow east-west corridor that extended from the Flint Hills in North Central Oklahoma to the foothills of the Sangre de Cristo Mountains in Northern New Mexico, USA. Across the study area, shell δ¹⁸O values (PDB scale) ranged from −4.1‰ to 1.2‰, while δ¹³C values ranged from −13.2‰ to 0.0‰. δ¹⁸O values of the shell aragonite were predicted with a published, steady state, evaporative flux balance model. The predicted values differed (with one exception) by less than 1‰ from locality averages of measured δ¹⁸O values. This similarity suggests that relative humidity at the time of snail activity is an important control on the δ¹⁸O values of the aragonite and emphasizes the seasonal nature of the climatic information preserved in the shells. Correlated δ¹³C values of coexisting Vallonia and Gastrocopta suggest similar feeding habits and imply that these genera can provide information on variations in southern Great Plains plant ecology. Although there is considerable scatter, multispecies, transect average δ¹³C values of the modern aragonite shells are related to variations in the type of photosynthesis (i.e., C₃, C₄) in the local plant communities. The results of this study emphasize the desirability of obtaining isotope ratios representing averages of many shells in a locale to reduce possible biases associated with local variations among individuals, species, etc., and thus better represent the “neighborhood” scale temporal and/or spatial environmental variations of interest in studies of modern and ancient systems.  相似文献   

Nickel speciation in Sebertia acuminata,a plant growing on a lateritic soil of New Caledonia     

Nicolas Perrier  Fabrice Colin  Tanguy Jaffré  Jean-Paul Ambrosi  Jérôme Rose  Jean-Yves Bottero 《Comptes Rendus Geoscience》2004,336(6):567-577

Nickel speciation in a nickel hyperaccumulating plant (Sebertia acuminata) and its associated soil of southern New Caledonia was studied using various analytical methods. The soil is formed of iron oxides (goethite, hematite), which contain almost all the nickel. The available nickel is probably linked to the organic matter in the litter. Sebertia acuminata, acts as a nickel pump, and concentrates the metal in its leaves. It partitions nickel and silica; nickel is concentrated in the cells (probably in the vacuoles) as organometallic complexes, whereas silica forms the framework of the cells, and the phytolithes. A thorough study of these plants seems essential in order to define the soil–plant relations, and to propose appropriate ways for ecological restoration. To cite this article: N. Perrier et al., C. R. Geoscience 336 (2004).  相似文献   

上海地区湿地水生维管束植物及其区系特征   总被引：10，自引：1，他引：10  

王伟  陆健健 《湿地科学》2004,2(3):171-175

在参照相关资料基础上，结合实地调查，得出上海地区湿地水生维管束植物共49科107属179种。从植物生态型和生活型等方面来划分，上海地区水生维管束植物可主要分为内陆河湖水生植物、河口海岸滩涂植物和湿生植物3种类型。从区系组成来看，包含5种以上的12个较大科构成了上海地区水生维管束植物的主体，其中禾本科和莎草科种类最多；区内各属种数都在10种以下，包含3种以上的属有19属，共79种，分别占总属数的17．8％和总种数的44．2％。从区系分布区类型来看，水生蕨类植物种主要有4种分布区类型，世界分布为主要类型；而水生种子植物属有13种分布区类型，其中6个热带分布类型共有39属，占总属数的61．9％，6个温带分布类型共有24属，占总属数的38．1％，表明上海地区水生种子植物区系具有偏热带性质。同时，讨论了水生维管束植物在湿地生态系统以及湿地生态恢复中的重要作用。  相似文献   

浙江天目山自然保护区珍稀濒危植物及其利用与保护     

刘鹏  陈立人 《山地学报》1996,(1)

天目山是浙江省珍稀濒危植物最丰富的地区，共有国家保护的珍稀濒危植物２５科、３４属、３７种，其中属二级保护１３种，三级保护２４种．论述了天目山珍稀濒危植物的区系特点、类型及地理分布，列举了它们的一些利用价值，最后提出了保护天目山珍稀濒危植物的一系列建议．  相似文献   

等高活篱笆试验研究的若干问题^*   总被引：4，自引：0，他引：4  

李秀彬  施迅 《地理研究》1996,15(1):66-72

本文讨论了等高活篱笆技术在设计、管理和效益分析等方面的原则与方法,指出应结合当地的自然条件和社会经济需求,围绕一两种主要功用来应用这种坡地持续利用技术。植物种类选择和篱笆的管理应以篱笆植物的属性、篱笆的形成及农林复合系统中各组分的和谐关系为依据。活篱笆改善生态的功能、社会经济效益宜采用费用-效益分析的方法进行评价。  相似文献   

Aquatic fungi growing on dead fragments of submerged plants   总被引：1，自引：0，他引：1  

Bazyli Czeczuga  Boenna Mazalska  Anna Godlewska  Elbieta Muszy&#x;ska 《Limnologica》2005,35(4):283-297

The authors investigated the dead fragments of 22 species of submerged plants in the water from three limnological and trophical different water bodies (spring, river and pond). A total of 184 species of aquatic fungi, including 119 zoosporic and 65 conidial species were found on the fragments investigated plants. The most common fungus species were Aphanomyces laevis, Saprolegnia litoralis, Pythium rostratum (zoosporic fungi) and Acrodictys elaeidicola, Anguillospora longissima, Angulospora aquatica, Lemonniera aquatica, Mirandina corticola, Tetracladium marchalianum, Tetracladium maxiliformis, Trinacrium subtile (conidial fungi).

Most fungus species were observed on the specimens of Elodea canadensis (33 fungus species), Hippuris vulgaris f. submersa (33), Myriophyllum spicatum (34) and Potamogeton crispus (33), fewest on Ceratophyllum demersum (24), Fontinalis dalicarlica and Potamogeton nitens (each 25).

The most fungi were growing in the water from River Supraśl (107), the fewest in the water from Pond Dojlidy (99). Some aquatic fungus species were observed in the water of only one of the three water bodies – in Pond Dojlidy (30), in Spring Jaroszówka (32) and in the River Supraśl (39) species. Seventy-five species growing only on fragments of single submerged plants. A number of zoosporic and conidial species (22 and four, respectively) appeared new to Polish waters. Out of these 119 zoosporic species, some are known as parasites or necrotrophs of fish.  相似文献   

云南白水台钙华水池中水化学日变化及其生物控制的发现   总被引：11，自引：0，他引：11  

刘再华  李强  孙海龙  汪进良  吴孔运 《水文地质工程地质》2005,32(6):10-15

为弄清云南白水台泉及其下游钙华水池中水化学的日变化,选取1号泉及其流经的两个钙华水池(6号和10号)作为研究对象并对其水温、pH值和电导率进行了自动监测。根据Ca2 、HCO3-与电导率存在的线性关系,用WATSPAC软件计算了水中方解石的饱和指数和PCO2。监测发现:泉水不存在显著的水化学日动态变化,而两个钙华水池表现出显著的日动态变化。其中10号钙华水池在白天温度较高时水中的CO2大量逸出并通过水下水生植物的光合作用加速了水中碳酸钙的沉积。6号钙华水池水生植物生长茂盛,其叶片和部分枝干露出水面,因而光合作用主要发生在空中,所以此处水化学表现为白天pH值降低和电导率升高的反常现象,即由温度主导的根呼吸作用,在白天释放更多的CO2进入水体而使沉积下来的碳酸钙重新溶解。  相似文献   

Validation and Application of Plants as Biomonitors of Trace Element Atmospheric Pollution – A Co-Ordinated Effort in 14 Countries     

B. Smodiš  M. L. Pignata  M. Saiki  E. CortÉs  N. Bangfa  B. Markert  B. Nyarko  J. Arunachalam  J. Garty  M. Vutchkov  H. Th. Wolterbeek  E. Steinnes  M. C. Freitas  A. Lucaciu  M. Frontasyeva 《Journal of Atmospheric Chemistry》2004,49(1-3):3-13

The International Atomic Energy Agency (IAEA) organized a co-ordinated research project (CRP) on Validation and application of plants as biomonitors of trace element atmospheric pollution analysed by nuclear and related techniques involving 14 participating countries. The CRPs objective was to identify appropriate bioindicators for local and/or regional application and validate them for general air pollution monitoring. Activities included quantification studies, research into spatial and time resolution for particular organisms, and physiological studies. A number of suitable bioindicators were identified in different parts of the globe and tested during the CRP. Sampling strategies were reviewed and the recommended approach adopted by the group. Appropriate sample preparation procedures were assessed and harmonised to the degree allowed by different geographic and climatic conditions in the participating countries. Two interlaboratory comparison exercises were carried out on lichen and moss materials. Results confirmed definite improvement in analytical performance of the participating laboratories, but also revealed possible inconsistencies due to different sample processing procedures. Several monitoring surveys were carried out and consequently pollution maps drawn for extended areas or countries. Overall results confirmed applicability of lower plants for assessing the degree of atmospheric pollution and provided several countries with effective monitoring tools not used before.  相似文献   

应用地理信息系统(MAPGIS)进行名优作物种植适宜区规划   总被引：3，自引：0，他引：3  

高艳芳 《物探化探计算技术》2000,22(3):257-261

利用地理信息系统对赣南全区的名优作物（烟草、茶叶）种植适宜区进行规划研究,取得了令人满意的成果。作者在文中具体介绍了ＭＡＰＧＩＳ的应用过程,包括基础信息的预处理、空间数据模型的建立、数据检索、空间分析及获取的最终成果等。  相似文献