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961.
The medicinal and aromatic plants resources of Uttarakhand, India offer significant opportunities of employment and livelihood for rural communities and contribute a large share in the medicinal and aromatic plants trade of India. With the growing trade of medicinal and aromatic plants resources in the global market, the medicinal and aromatic plants business of Uttarakhand is also continuously growing in terms of trade volume, value and market reach. But, considering the ecological importance as well as unregulated exploitations of these resources, the growing business activities in this sector appear incompatible to the sustainability agenda. Through a mini review, this study assesses the medicinal and aromatic plants sector of Uttarakhand and identifies key challenges that seem incompatible for resource and business sustainability and offers some prospective research directions essential for identifying pragmatic solutions to support sustainability in the sector. This review identifies nine key challenges to sustainability in Uttarakhandʼs medicinal and aromatic plants sector. It is therefore pertinent that future research focus on the prevailing challenges of the medicinal and aromatic plants sector of Uttarakhand to develop strategies for sustainable business prospects.  相似文献   
962.
磷酸二氢钙和氯化钾对乌栅土氮素淋失的影响   总被引:1,自引:0,他引:1  
利用土柱淋洗,研究了N、P、K共施对太湖乌栅土氮素(Urea-N、NH4+-N和NO3--N)淋失的影响.结果表明,在不施尿素的条件下,N的淋失以NO3--N为主,占淋失总氮(Urea-N、NH4+-N和NO3--N之和)的93.39%.施加尿素后,Urea-N、NH4+-N和NO3--N的淋失量明显增加,三者占淋失N的比例分别为3.95%、15.25%和80.80%,占施入N的比例分别为0.26%、0.80%和2.54%.Ca(H2PO4)2或KCl均可显著增加3种形态N的淋失,使3种形态N占淋失TN的比例分别为4.54%、24.11%、71.35%和3.45%、24.53%、72.02%,占施入N的比例分别为0.39%、1.86%、3.34%和0.32%、2.12%、4.06%.Ca(H2PO4)2和KCl共施对N素淋失存在着一定的交互作用,使3种形态N占淋失TN的比例分别达到4.10%、27.35%和68.55%,占施入N的比例分别为0.42%、2.60%和4.26%.不同形态N淋失的先后顺序为:Urea-N >NH4+-N>NO3--N,而淋失总量的顺序为:Urea-N < NH4+3--N.  相似文献   
963.
分步沉淀法处理酸性矿山废水   总被引:1,自引:0,他引:1  
采用分步沉淀工艺处理酸性矿山废水,考察了工艺条件对废水中有价金属元素回收效果的影响。实验结果表明:Ca(OH)_2为适宜的废水pH调节剂;调节废水pH至4.00左右并投加0.05 mL/L的H_2O_2,可首先去除Fe~(2+)及Fe~(3+),得到富Fe渣(w(Fe)=51.00%);调节废水pH至6.00~6.50,先投加50 mg/L的Na_2S,去除废水中的Cu~(2+),获得富Cu渣(w(Cu)=10.89%),再将Na_2S的投加量增至100 mg/L,去除废水中的Zn与Mn,获得富Zn-Mn渣(w(Cu)=2.37%,w(Mn)=6.79%,w(Pb)=1.61%);进一步调节废水pH至8.40,可去除剩余的Zn、Mn及其他重金属。分步沉淀工艺处理后的废水可达标排放,产生的富Fe渣、富Cu渣及富Zn-Mn渣可直接出售或具有利用价值。分步沉淀工艺可实现有价金属元素的高效回收,大幅度降低废水处理的实际成本,值得工程应用与推广。  相似文献   
964.
我国风电行业每年产生大量热固性玻璃钢废弃物,这些废弃的热固性复合材料叶片、机舱罩等,在处置过程中广泛存在资源浪费和环境污染问题。对风电行业废玻璃钢的来源、产生量进行分析,概述废玻璃钢的生态毒性,阐述当前玻璃钢废弃物资源化处置技术及其优缺点,并提出风电行业废玻璃钢资源化处置技术的未来发展方向。  相似文献   
965.
As a result of the '16-year drought' that Burkina Faso experienced from the late 1970s to the mid-1980s, there has been significant movement of people from the north of the country to the south. The large numbers of people that were displaced as a result of this natural disaster put pressure on the production systems of the south and caused concern amongst development organisations that environmental degradation would follow. Through a 2-year research period, using participatory approaches, it was found that despite a doubling of the population and the introduction of foreign production systems, the process of communal land control has significantly limited environmental degradation. This paper explains how customary law has controlled the settlement of immigrants (the Mossi and Fulani) and how it has overseen land allocation in three villages. The conclusions of the study indicate that, firstly, the customary law mechanisms in the three villages are effective in addressing communal resource use and, secondly, there is an evolution in customary law systems as they respond to local change. Received: 24 February 1999 · Accepted: 15 May 1999  相似文献   
966.
可再生能源资源评价体系与方法   总被引:8,自引:0,他引:8  
本文根据可再生能源资源的特性以及与技术、市场之间的内在联系,构建了可再生能源的资源评价体系,分析了资源量、生产率、生产经济性及不确定性分析等各环节中的具体评价方法和指标框架,并提出了最小和最大经济获利开发量以度量资源生产的经济性潜力  相似文献   
967.
ABSTRACT: Federal spending on water resource development projects exceeds $10 billion annually. This paper examines the economic theory and practice on which the Federal water resource development plans are based. Existing theoretical and applied problems result in overinvestment. These include 1) no standard of value for the tradeoff of environmental objectives with economic objectives; 2) benefits based on “willingness to pay,” but beneficiaries pay only a fraction of a project's costs; 3) beneficiaries “shop around” among program purposes in order to reduce their commitments; and 4) benefit/cost (B/C) analyses are based on a discount rate, which is consistently below the Federal borrowing rate. Furthermore, the Government Accounting Office (GAO) frequently finds that the agency regulations are inadequate and result in inconsistent and questionable benefit computations. The President has proposed a series of water policy reforms, to reduce some of the apparent overinvestment in water resource development, but fundmental corrective action rests with the members of Congress.  相似文献   
968.
ABSTRACT The American Indian occupies a unique place in the federal system of government There are indications that this relationship will continue and that Indian reservations are at the threshold of economic development. As this occurs, the nature and extent of Indian water rights becomes more important to Indian and non-Indian alike. The determination of these rights is a matter of more than judicial decisions. To a large degree the determination of these rights will rest in the non-judicial arena and will be influenced by the perceptions of those rights held by Indians and water allocation officials, both state and federal. If the perceptions of these political actors are not congruent, then political conflict will occur as the rights become more important. To depend solely upon the judicial system to resolve these conflicts entails risks and costs to both Indians and to allocating officials. Indians are taking seriously the federal policy of Indian self-determination, and water allocation officials run decided risks in failure to realize this. An alternative suggested is to include Indians as consulting parties when decisions are being made that affect Indian interests.  相似文献   
969.
ABSTRACT. A hybrid computer program was developed to predict the water and salt outflow from a river basin in which irrigation is the major user of water. The model combines a chemical model which predicts the quality of water percolated through a soil profile with a general hydrologic model. The chemical model considers the reactions that occur in the soil, including the exchange of calcium, magnesium, and sodium cations on the soil complex, and the dissolution and precipitation of gypsum and lime. The chemical composition of the outflow is a function of these chemical processes within the soil, plus the blending of undiverted inflows, evaporation, transpiration, and the mixing of sub surface return flows with groundwater. The six common ions of western waters, namely calcium (Ca++), magnesium (Mg++), sodium (Na+), sulfate (SO4=), chloride (Cl?), and bicarbonate (HCO3?) were considered in the study. Total dissolved solids (TDS) outflow was obtained by adding the individual ions. The overall model operates on a monthly time unit. The model was tested on a portion of the Little Bear River basin in northern Utah. The model successfully simulated measured outflows of water and each of the six ions for a 24-month period. The usefulness of the model was demonstrated by a management study of the prototype system. For example, preliminary results indicated that the available water supply could be used to irrigate additional land without unduly increasing the salt outflow from the basin. With minor adjustments the model can be applied to other hydrologic areas.  相似文献   
970.
ABSTRACT Attitudes toward the development of the American West have undergone important changes over the past century just as the nature of water resources as factors in development have changed. Viewing these changes processually, stages for water resources definition and use can be identified in the total process of western cultural development. The first stage involves the value of water resource development as a stimulus to population and economic growth in the West. The second stage, still in process', adopts a dominant cultural norm which sees water resource development as inevitable if not necessary to keep up with growth. A third stage to this evolutionary process is incipient. Future cultural values and thinking with respect to water resource development will be to look at development as a means for controlling or managing both the location and quantity of population and economic growth. To this end planners will have to become concerned with the questions of human adaptation. Concern will have to be given to the problems of getting a living which enables individuals to meet the subsistence needs of self and family, to establishing community which provides for cooperation among individuals and the management of conflict, to establishing improved communication which promotes interpersonal interaction, and for fostering innovation which provides the new ideas necessary to adapt to new environmental situations.,  相似文献   
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