首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   12篇
  免费   0篇
废物处理   1篇
环保管理   5篇
综合类   1篇
基础理论   3篇
评价与监测   2篇
  2019年   1篇
  2011年   1篇
  2010年   2篇
  2005年   2篇
  1999年   1篇
  1997年   1篇
  1993年   2篇
  1991年   1篇
  1990年   1篇
排序方式: 共有12条查询结果,搜索用时 17 毫秒
1.
ABSTRACT: Irrigation development in Saskatchewan was initiated as an instrument to bring forth regional stability through drought proofing and diversification in the agricultural sector. This development has been surrounded by controversies. Particularly, some critics questioning its economic value to the farmer. In this study, irrigation on a farm is compared as a growth alternative to the expansion of dryland farming. Under relatively conservative machine replacement policies, modest family withdrawals, government subsidized irrigation loans, and relatively favorable gross operating margins, irrigation can be a profitable undertaking in the South Saskatchewan River Basin.  相似文献   
2.
ABSTRACT: Presence of a river in an urban setting may contribute positively to an aesthetically pleasing environment. Such aesthetic effects are not typically linked to specific economic activities and occur, for example, when residents are exposed to a river-view. Qualities enhancing the aesthetic value of the river include the presence of parks, trails, and vegetation along the riverbanks. The value of aesthetic amenities provided by the South Saskatchewan to the City of Saskatoon residents was estimated in this study using non-market methods. The implicit price of the river view was estimated using the Hedonic Price Model, whereas value through willingness to pay for property taxes or higher rents were also estimated using actual market data. The total annual value of the river to the City of Saskatoon through addition of aesthetic amenities was estimated at $1.2 million in 1989 dollars.  相似文献   
3.
Handmade paper and cardboard industries are involved in processing of cellulosic and ligno-cellulosic substances for making paper by hand or simple machinery. In the present study solid sludge and effluent of both cardboard and handmade paper industries was collected for developing a mushroom cultivation technique to achieve zero waste discharges. Findings of present research work reveals that when 50% paper industries waste is used by mixing with 50% (w/w) wheat straw, significant increase (96.38%) in biological efficiency over control of wheat straw was observed. Further, cultivated basidiocarps showed normal morphology of stipe and pileus. Cross section of lamellae did not show any abnormality in the attachment of basidiospores, hymenal trama and basidium. No toxicity was found when fruiting bodies were tested chemically.  相似文献   
4.
The present paper deals with the rich avifauna available at Jamwa Ramgarh Lake of Rajasthan in India. More than 100 species of birds belonging to 38 families were recorded at lake during the year 2002, maximum species were sighted during the winter season. Due to scanty rainfall in 2002, this lake was also affected and had only one-fourth of water of its total capacity, which affected the numbers of migratory waterfowl also. In the wetland most water birds were found to be migratory and few being resident. Some rare, endangered, uncommon, vulnerable, threatened and near threatened species of birds those already listed in Red Data Book were sighted.  相似文献   
5.
Droughts can have severe negative effects on the environment, society and economy. The drought of 2001–2002 caused severe strain on economic and social activities in western Canada, particularly on rural communities through changes in water resources. This paper examines physical and social vulnerabilities and associated adaptation measures undertaken and the adaptive capacity in communities in the South Saskatchewan River Basin, Canada. Although all of these communities were exposed to the 2001–2002 drought, they had different levels of impacts, resulting in different types of drought adaptation measures, some due to experience with previous droughts and some in response to the 2001–2002 drought. Communities with unreliable water supply were the most vulnerable to these droughts. This vulnerability resulted in historic adaptations being implemented (e.g., Hanna, Alberta) and re-active adaptations (e.g., Cabri, Saskatchewan). It is important to examine the effectiveness of the current adaptive strategies to cope with more extensive and extended drought situations. First Nation communities, such as the Kainai Blood Indian Reserve, have many social and environmental issues but the impacts from the drought were minor. The Reserve had implemented economic changes in the late 1980s to make it less vulnerable to drought but resulted in negative impacts to the Reserve’s social health. It is imperative to determine how vulnerable First Nation communities are and will to improve future adaptive capacity. This paper provides a snap shot view of how Canadian Prairie Communities have adapted to drought and how vulnerable they are to future drought situations.  相似文献   
6.
The present investigation is a case study of Lucknow, the main metropolis in Northern India, which succumbs to a major problem of municipal solid waste and its management. A qualitative investigation using strengths, weaknesses, opportunities and threats analysis (SWOT) has been successfully implemented through this community participation study. This qualitative investigation emphasizes the limited capabilities of the municipal corporation's resources to provide proper facilitation of the municipal solid waste management (MSWM) services without community participation in Lucknow city. The SWOT analysis was performed to formulate strategic action plans for MSWM in order to mobilize and utilize the community resources on the one hand and municipal corporation's resources on the other. It has allowed the introduction of a participatory approach for better collaboration between the community and municipal corporation in Lucknow (India). With this stakeholder-based SWOT analysis, efforts were made to explore the ways and means of converting the possible "threats" into "opportunities" and changing the "weaknesses" into "strengths" regarding a community-based MSWM programme. By this investigation, concrete strategic action plans were developed for both the community and municipal corporation to improve MSWM in Lucknow.  相似文献   
7.
Methane is primarily a biogenic gas, which is implicated in global climate change. Among all the sources of methane emission, paddy fields form the most dominant source. An experiment was conducted with a common paddy crop (Oryza sativa var. Vishnuparag) by amending the soils with different organic manures and biofertilizers with a view to find out an inexpensive strategy to mitigate methane emission from the rice-fields. The results revealed that there was a seasonal change in the CH4 flux, registering a peak at heading stage in all treatments. The application of rice straw before flooding and the biofertilizer after flooding enhances CH4 efflux from the rice-fields significantly, while composts of cowdung and leaves did not stimulate CH4 production and, rather, decreased CH4 fluxes. As soil pH and temperature were optimum for methanogenesis, it was likely that the organic C and the redox potential mainly modulated methane production and its emission through rice plants.  相似文献   
8.
ABSTRACT: Water abundance has led most North American societies to use water freely without priorizing its use. As water scarcity becomes reality in the southern part of Saskatchewan, planners and managers of water require information about the value of water in irrigation, as well as in alternative uses. In this study, the value of water to the producer in irrigation is developed both for the short and long run. The basis of this imputation is a derived demand function for water using linear programming. Water demand was bound to be inelastic at lower prices, and highly elastic at higher prices. The short-run value of water varied between $0.44 and $127.82 (1986 dollars) per acre-foot for different levels of product prices. However, the long-run value was estimated between zero and $1.59 per acre-foot of water.  相似文献   
9.
ABSTRACT: The on-farm economic effectiveness of government capital grants, subsidized interest rates, and the Canadian Wheat Board (CWB) delivery quota levels in terms of adoption and/or expansion of irrigation in Saskatchewan is tested. The annualized net income at 5 and 20 years of three representative farm types - a dryland grain farm, an irrigated grain farm, and an irrigated mixed farm - are used in the analysis. Tradeoffs between income levels and the risks associated with adoption/expansion of irrigation are evaluated using mean-standard deviation tradeoff and stochastic dominance. Risk differences arise due to reduced business risk through higher yields and increased financial risk through higher borrowing when adopting or expanding irrigation. Capital grants and subsidized interest rates are effective policy measures for dryland grain farms adopting irrigation because the farms are left in a similar risk position. However, these grants and interest rates are not effective policy measures in the medium run (5 years) for irrigated grain farms expanding irrigation because they lower the farm's risk efficiency. In the long run (20 years), the capital grants and subsidized interest rates need to be combined with open CWB delivery quotas before the risk position can be improved for irrigated grain farms expanding irrigation. Finally, the grants and interest rates need to be combined with increased irrigated hay production for risk efficiency to increase in both the medium and long run (5 and 20 years, respectively) on irrigated mixed farms expanding irrigation.  相似文献   
10.
The plant foliar surface is the most important receptor of atmospheric pollutants. It undergoes several structural and functional changes when particulate-laden air strikes it. In the present investigation, ten annual plant species viz., Abelmoschus esculentus, Celosia cristata, Coleus blumei, Cyamopsis tetragonolobus, Gomphrena globosa, Impatiens balsamina, Ocimum sanctum, Phaseolus vulgaris, Solanum melongena, and Zinnia elegans were studied for their growth parameters and leaf morphological features. They were subjected to dust experimentally for 60 days. The micro-morphological traits like wax, cuticle, epidermis, stomata, and trichomes were observed under light and scanning electron microscopes. Remarkable differences in the growth parameters and micro-morphological features were recorded in the dust-treated plants when compared to the respective controls. The reduction in growth parameters, the size of epidermal cells, and stomata were reduced and cuticle damage was also observed. The relative proportion of fine particles, which play a major role in hampering the overall growth of a plant, was higher in comparison to ultra-fine and coarse particles.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号