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1.
葛藤的饲用价值及其在攀西地区畜牧业中的应用   总被引:7,自引:0,他引:7  
葛藤的根、茎、枝、叶不但富含蛋白质、碳水化合物等易消化吸收的营养物质,而且还具有防治动物疾病的作用,是饲药合用、牲畜和家禽喜食的优质牧草和饲料.研究了葛藤的饲用价值和饲用方法,提出了在攀西地区畜牧业中的应用建议.  相似文献   

2.
马桑(C.sinica)属马桑科马桑属的一种落叶灌木.具有生长快、适应性强,耐干旱瘠薄土壤的特点.马桑喜光,在阳坡上生长良好,郁闭度0.4以下的疏林内也能生长.其鲜嫩叶含氮0.5%~0.6%,磷0.09%~0.15%、钾0.2%~0.34%,每500kg 叶的肥效相当于12.5~15kg 硫酸铵、2~4kg 过磷酸钙,2~3.5kg 硫酸钾.马桑鲜叶富含营养物质,是养蚕的良好原料.  相似文献   

3.
本文对穿心莲内酯、水飞蓟素、颅通定、利血平、薯芋皂素的来源、含量、分布、应用、市场及提取方法等方面作了简要概述,指出了开发利用途径。  相似文献   

4.
中科院成都生物研究所1986年受成都市科委委托的项目——淀粉废渣(包括玉米,红苕、木薯、芭蕉芋等淀粉)生产蛋白饲料的研究,经科研人员深入系统研究,将  相似文献   

5.
通过对四姑娘山自然保护区四川红杉林、岷江冷杉林、中国沙棘林3种典型植被类型林下枯落物的实验分析,四姑娘山自然保护区内四川红杉林、岷江冷杉林、中国沙棘林林下枯落物数量、持水能力要高于一般的针叶林和阔叶林,四川红杉林、岷江冷杉林、中国沙棘林林下枯落物最大持水率差异不显著(P=0.080)。LSD多重比较结果可知,中国沙棘林最大持水率显著高于岷江冷杉林、四川红杉林,而岷江冷杉林、四川红杉林间最大持水率差异不显著。  相似文献   

6.
人参(见图1)是国家二级保护植物。人参的根茎叶及果实均可入药,是极其珍贵的药材。野生人参多生长在以红松为主的针阔混交林及阔叶林下,喜生长在腐质值层肥厚,排水良好,荫蔽适宜的地方。目前国内只有吉林省的长白山区各县,黑龙江的大、小兴安岭有野生人参生长,河北省兴隆县雾灵山等地亦有少量分布。  相似文献   

7.
塔里木河流域的自然环境保护问题   总被引:1,自引:0,他引:1  
塔里木河是我国最长的内陆河,也是世界上最大的内陆河之一。流域光照热量充足,适合喜温作物和长绒棉生长。土地资源丰富,约占全疆宜农荒地九分之一,在塔里木盆地各荒区中,质量居于第一。草场面积宽阔,适合耐粗饲、抗干旱,能够生产珍贵羔皮的三北羊放牧。胡杨林虽经严重破坏,但保留下来的面积仍是我国及世界最集中的地区。灌溉水源基本不缺,在合理利用情况下,尚能满足现有农、林、牧业灌溉需要。  相似文献   

8.
珠芽魔芋种子5苗接力生长当年形成商品芋技术   总被引:1,自引:0,他引:1  
首次提出珠芽魔芋种子具有5苗接力生长的生物学特性。种子能在一个不间断的生长周期中积累最大生物产量,避免魔芋需反复"换头"种植3—4年才能收获商品芋的低产生长模式,使魔芋的膨大系数由块茎的低于10倍提高到种子最高约7000倍,所获地下球茎重量平均达1560g。采用种子种植当年即可获用于加工的商品芋,消除了魔芋种植过程中固有的风险,使魔芋由低产作物变成高产作物,魔芋多糖总量将实现跨越式增长。  相似文献   

9.
本文对穿心莲内酯,水飞蓟素、颅通定,利血平,薯芋皂素的来源,含量,分布,应用,市场及提取方法等方面作了简要概述,指出了开发利用途径。  相似文献   

10.
本文依据实地监测资料,分析了孔雀河下游断流河道的植被退化特征及植物类群与环境的关系,旨在为荒漠河岸生态系统保护与恢复提供参考。结果表明:胡杨作为孔雀河下游荒漠河岸林的建群种及优势种,顺沿河道呈现出死亡数增加的趋势;存留胡杨以成年木较多,存留格局为集聚型。K1断面物种多样性及丰富度平均值都较高,反映出群落相对的稳定性;K2断面多样性与丰富度都较低,且均匀度波动较大,反映出群落的不稳定性。CCA排序把植被分为深水位-适盐类群、深水位-耐盐类群与浅水位-喜盐类群,其中以胡杨为优势的深水位-适盐类群维持了较好的土壤养分,而以盐爪爪、盐穗木为优势的浅水位-喜盐类群,占据了地下水埋深浅、盐分含量高、养分极端贫瘠的生境。  相似文献   

11.
Global land use patterns and increasing pressures on water resources demand creative urban stormwater management. Strategies encouraging infiltration can enhance groundwater recharge and water quality. Urban subsoils are often relatively impermeable, and the construction of many stormwater detention best management practices (D-BMPs) exacerbates this condition. Root paths can act as conduits for water, but this function has not been demonstrated for stormwater BMPs where standing water and dense subsoils create a unique environment. We examined whether tree roots can penetrate compacted subsoils and increase infiltration rates in the context of a novel infiltration BMP (I-BMP). Black oak (Quercus velutina Lam.) and red maple (Acer rubrum L.) trees, and an unplanted control, were installed in cylindrical planting sleeves surrounded by clay loam soil at two compaction levels (bulk density = 1.3 or 1.6 g cm(-3)) in irrigated containers. Roots of both species penetrated the more compacted soil, increasing infiltration rates by an average of 153%. Similarly, green ash (Fraxinus pennsylvanica Marsh.) trees were grown in CUSoil (Amereq Corp., New York) separated from compacted clay loam subsoil (1.6 g cm(-3)) by a geotextile. A drain hole at mid depth in the CUSoil layer mimicked the overflow drain in a stormwater I-BMP thus allowing water to pool above the subsoil. Roots penetrated the geotextile and subsoil and increased average infiltration rate 27-fold compared to unplanted controls. Although high water tables may limit tree rooting depth, some species may be effective tools for increasing water infiltration and enhancing groundwater recharge in this and other I-BMPs (e.g., raingardens and bioswales).  相似文献   

12.
葛根保健食品的开发及利用   总被引:9,自引:0,他引:9  
作者论述了葛根的生长习性、资源分布、保健药效、化学组成及其加工特性,并在此基础上,提出了利用我国野葛自然资源优势开发生产系列保健食品的途径。  相似文献   

13.
Key concepts of Risk Society as elaborated by Ulrich Beck and others (Beck, U., 1992 (trans. Mark Ritter). The Risk Society. Sage Publications, London. Beck, U., 1995, Ecological Politics in the Age of Risk. Polity Press, Cambridge. Beck, U., 1999, World Risk Society. Polity Press, Cambridge. Giddens, A., 1994, Beyond Left and Right. Polity Press, Oxford. Beck, U., Giddens, A. and Lash, S., 1994, Reflexive Modernisation: Politics, Tradition and Aesthetics in the Modern Social Order. Stanford University Press, Stanford. Beck, U., Bonss, W. and Lau, C., 2003, Theory, Culture & Society 2003, Sage, London, 20(2), pp. 1-33.) are illuminated though a case study of managed environmental risk, namely the hexachlorobenzene (HCB) controversy at Botany, a southeast suburb of Sydney. We observe the way multiple stakeholder decision-making plays out a number of Risk Society themes, including the emergence of 'unbounded risk' and of highly 'individualised' and 'reflexive' risk communities. Across several decades, the events of the HCB story support Risk Society predictions of legitimacy problems faced by corporations as they harness technoscientific support for innovation in their products and industrial processes without due recognition of social and environmental risk. Tensions involving identity, trust and access to expert knowledge advance our understanding of democratic 'sub-political' decision-making and ways of distributing environmental risk.  相似文献   

14.
Ecosystems, though impacted by global environmental change, can also contribute to the adaptation and mitigation of such large scale changes. Therefore, sustainable ecosystem management is crucial in reaching a sustainable future for the biosphere. Based on the published literature and publicly accessible data, this paper discussed the status and trends of forest, grassland, and wetland ecosystems in China that play important roles in the ecological integrity and human welfare of the nation. Ecological degradation has been observed in these ecosystems at various levels and geographic locations. Biophysical (e.g., climate change) and socioeconomic factors (e.g., intensive human use) are the main reasons for ecosystem degradation with the latter factors serving as the dominant driving forces. The three broad categories of ecosystems in China have partially recovered from degradation thanks to large scale ecological restoration projects implemented in the last few decades. China, as the largest and most populated developing nation, still faces huge challenges regarding ecosystem management in a changing and globalizing world. To further improve ecosystem management in China, four recommendations were proposed, including: (1) advance ecosystem management towards an application-oriented, multidisciplinary science; (2) establish a well-functioning national ecological monitoring and data sharing mechanism; (3) develop impact and effectiveness assessment approaches for policies, plans, and ecological restoration projects; and (4) promote legal and institutional innovations to balance the intrinsic needs of ecological and socioeconomic systems. Any change in China’s ecosystem management approach towards a more sustainable one will benefit the whole world. Therefore, international collaborations on ecological and environmental issues need to be expanded.  相似文献   

15.
铅锌矿业废弃地草本植物重金属耐性研究   总被引:9,自引:0,他引:9  
杨刚  伍钧  唐亚  谢丽苹  谢晴 《四川环境》2006,25(4):18-21,38
本文调查了四川甘洛铅锌矿废弃矿区和尾矿库区自然生长的15种草本植物,分析了其体内重金属(Pb、Zn、Cd)的含量,并对植物的重金属耐受性作了初步探讨。研究表明,在所采集的15种草本植物中,地上部分以小飞蓬对Pb、Zn、Cd的富集量最高;地下部分富集量则表现出较大的种间差异性,野烟对Pb的积累量最高,假酸浆对Zn的积累量最高,水蓼对Cd的积累量最高,但均未达到“超积累植物”的标准。  相似文献   

16.
The main aim of this study was to determine how the application of a mulch cover (a mixture of household biocompost and woodchips) onto heavy metal-polluted forest soil affects (i) long-term survival and growth of planted dwarf shrubs and tree seedlings and (ii) natural revegetation. Native woody plants (Pinus sylvestris, Betula pubescens, Empetrum nigrum, and Arctostaphylos uva-ursi) were planted in mulch pockets on mulch-covered and uncovered plots in summer 1996 in a highly polluted Scots pine stand in southwest Finland. Spreading a mulch layer on the soil surface was essential for the recolonization of natural vegetation and increased dwarf shrub survival, partly through protection against drought. Despite initial mortality, transplant establishment was relatively successful during the following 10 yr. Tree species had higher survival rates, but the dwarf shrubs covered a larger area of the soil surface during the experiment. Especially E. nigrum and P. sylvestris proved to be suitable for revegetating heavy metal-polluted and degraded forests. Natural recolonization of pioneer species (e.g., Epilobium angustifolium, Taraxacum coll., and grasses) and tree seedlings (P. sylvestris, Betula sp., and Salix sp.) was strongly enhanced on the mulched plots, whereas there was no natural vegetation on the untreated plots. These results indicate that a heavy metal-polluted site can be ecologically remediated without having to remove the soil. Household compost and woodchips are low-cost mulching materials that are suitable for restoring heavy metal-polluted soil.  相似文献   

17.
Composting and the application of compost to the soil follow the principle of recycling and sustainability. Compost can also have a positive effect on physical, chemical, and biological soil parameters. However, little is known about the origin, concentration, and transformation of persistent organic pollutants (POPs) in compost. We therefore compiled literature data on some priority POPs in compost and its main feedstock materials from more than 60 reports. Our data evaluation suggests the following findings. First, median concentrations of Sigma 16 polycyclic aromatic hydrocarbons (PAHs), Sigma 6 polychlorinated biphenyls (PCBs), and Sigma 17 polychlorinated dibenzo-p-dioxins and -furans (PCDD/Fs) were higher in green waste (1803, 15.6 microg/kg dry wt., and 2.5 ng international toxicity equivalent [I-TEQ]/kg dry wt.) than in organic household waste (635, 14.6 microg/kg dry wt., and 2.2 ng I-TEQ/kg dry wt.) and kitchen waste (not available [NA], 14.9 microg/kg dry wt., 0.4 ng I-TEQ/kg dry wt.). The POP concentrations in foliage were up to 12 times higher than in other feedstock materials. Second, in contrast, compost from organic household waste and green waste contained similar amounts of Sigma 16 PAHs, Sigma 6 PCBs, and Sigma 17 PCDD/Fs (1915, 39.8 microg/kg dry wt., and 9.5 ng I-TEQ/kg dry wt., and 1715, 30.6 microg/kg dry wt., and 8.5 ng I-TEQ/kg dry wt., respectively). Third, concentrations of three-ring PAHs were reduced during the composting process, whereas five- to six-ring PAHs and Sigma 6 PCBs increased by roughly a factor of two due to mass reduction during composting. Sigma 17 PCDD/Fs had accumulated by up to a factor of 14. Fourth, urban feedstock and compost had higher POP concentrations than rural material. Fifth, the highest concentrations of POPs were usually observed in summer samples. Finally, median compost concentrations of POPs were greater by up to one order of magnitude than in arable soils, as the primary recipients of compost, but were well within the range of many urban soils. In conclusion, this work provides a basis for the further improvement of composting and for future risk assessments of compost application.  相似文献   

18.
China is rich in energy plant resources. In this article, 64 plant species are identified as potential energy plants in China. The energy plant species include 38 oilseed crops, 5 starch-producing crops, 3 sugar-producing crops and 18 species for lignocellulosic biomass. The species were evaluated on the basis of their production capacity and their resistance to salt, drought, and/or low temperature stress. Ten plant species have high production and/or stress resistance and can be potentially developed as the candidate energy plants. Of these, four species could be the primary energy plants in China: Barbados nut (Jatropha curcas L.), Jerusalem artichoke (Helianthus tuberosus L.), sweet sorghum (Sorghum bicolor L.) and Chinese silvergrass (Miscanthus sinensis Anderss.). We discuss the use of biotechnological techniques such as genome sequencing, molecular markers, and genetic transformation to improve energy plants. These techniques are being used to develop new cultivars and to analyze and manipulate genetic variation to improve attributes of energy plants in China.  相似文献   

19.
For decades, wind erosion has triggered dust and sand storms, buffeting Beijing and areas of northwestern China to the point of being hazardous to human health while rapidly eroding crop and livestock productivity. The EPIC (Environmental Policy Integrated Climate) field-scale simulation model was used to assess long-term effects of improved crop rotations and crop residue management practices on wind erosion in Wuchuan County in Inner Mongolia. Simulation results indicate that preserving crop stalks until land is prepared by zone tillage for the next year's crop in lieu of using them as a source of heating fuel or livestock fodder significantly reduces wind erosion by 60%. At the same time, grain and potato (Solanum tuberosum L.) yields were maintained or improved. Significant reductions in erosion, 35 to 46%, also resulted from delaying stalk removal until late January through late April. Yearly wind erosion was concentrated in April and May, the windiest months. Additionally, the use of alternative crop rotations resulted in differences in wind erosion, largely due to a difference in residue stature and quality and differences in biomass produced. As a result, altering current crop rotation systems by expanding corn (Zea mays L.), wheat (Triticum aestivum L.), and millet [Sorghum bicolor (L.) Moench] and reducing potato and pea (Pisum sativum L.) production significantly reduced simulated wind erosion, thus diminishing the severity of dust and sand storms in northwestern China. Saving and protecting topsoil over time will sustain land productivity and have long-term implications for improving conditions of rural poverty in the region.  相似文献   

20.
Importance of insects in environmental impact assessment   总被引:9,自引:0,他引:9  
Insects are particularly suited for use in environmental impact assessment (e.i.a.) because of their high species diversity, ubiquitous occurrence, and importance in the functioning of natural ecosystems. Examples are given of the use of insects in the predictive phase of e.i.a., in the monitoring and assessment phase, and in the much rarer instance of an e.i.a. that includes both of these phases. The importance of working at the species level to understanding the results of e.i.a. is emphasized.  相似文献   

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