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941.
Nguyen?Bich?HongEmail author Mitsuyasu?Yabe 《Environment, Development and Sustainability》2017,19(4):1247-1263
Irrigation is indispensable to overcome insufficient rainfall and to achieve a stabilized yield for tea production. As the severe scarcity of water resources because of climate change, water conservation through efficient irrigation has turned into a vital strategy for tea sector in solving this rising challenge. This paper analyzes irrigation water use efficiency of small-scale tea farms in Vietnam and identifies its determinants applying stochastic frontier analysis. Results showed that under decreasing returns to scale, the mean irrigation water use efficiency was 42.19 %, indicating the existence of substantial water waste. If farmers become more efficient in using water, saving 57.81 % of irrigation water is possible unaccompanied by reducing the observed output. The factors affecting tea farms’ irrigation water use efficiency were investigated by Tobit model. Gender, water shortage awareness, soil and water conservation practice, off-farm income share, extension services access and well water utilization showed significant influence on the efficiency of irrigation water. The study’ results provide insights to policymakers in implementing better water resource management amid climate change. 相似文献
942.
Enhancing viability of biofuel-based decentralized power projects for rural electrification in India
Debajit?PalitEmail authorView authors OrcID profile Ramit?Malhotra Sanjay?Mande 《Environment, Development and Sustainability》2017,19(1):263-283
Decentralized power generation, using locally available biofuels from non-edible oilseeds, is an option for rural electrification in many developing countries. However, due to prevailing high price of non-edible oilseeds, such as Jatropha curcas, the cost of electricity generation is very high. This paper provides detailed financial analysis of straight vegetable oil (SVO)-based decentralized power project and proposes an innovative model for enhancing their financial viability. While for implementing agency operational cost recovery is the key for viability, affordable tariff is crucial for end-users. The paper attempts to estimate minimum desired price of electricity from the stakeholders' (producer and users) perspective using data gathered from selected operational SVO-based power generation projects in India. Analysis carried out in this paper indicates that operating the decentralized power plant at higher capacity utilization factor, by introduction of productive load, and differentiated tariffs for commercial and domestic consumers may not alone be sufficient to achieve the financial viability. The paper proposes an innovative integrated model of using biogas, obtained from the by-product de-oiled cake of non-edible oilseeds, as a feedstock for power generation, instead of using the SVO in engines. This reduces the fuel cost of power generation, thereby helping to bring down the tariff within the paying capacity of rural consumers. The main produce, viz. extracted non-edible oil, which was otherwise used as fuel for generating power, can be sold in local market for earning revenue, thereby enhancing the project’s economic viability. This paper sets forth the proposed integrated model as a viable biofuel-based decentralized power project for sustainable rural development in areas with adequate availability of oilseeds. 相似文献
943.
Belarmino?Carneiro?da?Silva Neto André?Luiz?Borba?do?Nascimento Nicola?Schiel R?mulo?Romeu?Nóbrega AlvesEmail author Antonio?Souto Ulysses?Paulino?AlbuquerqueEmail author 《Environment, Development and Sustainability》2017,19(5):1795-1813
The hunting of wild animals remains a common activity in various parts of the world, especially in rural communities with poor socioeconomic conditions. To investigate patterns of mammal hunting, this study adopted a rural community located in semiarid Brazil as a model to test whether variables such as perceived abundance, activity period (day or night) and animal biomass could influence the consumption potential of mammal taxa. For this study, a checklist/interview technique using 32 photographs of mammals recorded in the region and two photographs of species that did not occur in the region, which acted as “control” species, was used, in addition to other visual stimuli and free lists. All species presented in the photographs, with the exception of the “control” species, were recognized as occurring in the region. Fourteen species were cited as being those most hunted locally. The species cited as most hunted had an average perceived abundance higher than the group of the least-hunted species. However, there was no significant relationship between hunting of a species and its locally perceived abundance. No significant difference in hunting pressure between diurnal and nocturnal species was found, nor was a relationship between animal biomass and hunting pressure observed. Our findings suggest that perceived abundance is an important factor for choosing a resource fauna, but other factors such as intended use, meat flavor and vulnerability to hunting, among others, may influence the potential use of a species. 相似文献
944.
Walter?Alfredo?Salas-ZapataEmail authorView authors OrcID profile Leonardo?Alberto?Ríos-Osorio Jorge?Antonio?Mejía-Escobar 《Environment, Development and Sustainability》2017,19(6):2237-2252
The term ‘sustainability science’ has been employed to refer to a scientific trend, movement or program aimed at studying problems related to human–nature interactions. However, since it does not have its own set of principles for knowledge building and lack of a definition of a study object, sustainability science is not a science, at least in the usual sense of the word. A study object is the conceptual delimitation of the problems tackled by a science, and therefore, its search in the context of a science of sustainability requires exploring different notions of sustainability. This article presents different perspectives on the concept of sustainability and analyzes the viability to assume them as study object of sustainability science. Such exploration demands concepts based on a processual ontology that directs the researcher toward the dynamic, historic and temporal and social-ecological character of problems of unsustainability. The concept of social-ecological resilience seems to comply with such requirements. 相似文献
945.
Mariam?Ameli Saeed?MansourEmail author Amir?Ahmadi-Javid 《Environment, Development and Sustainability》2017,19(6):2443-2456
In today’s competitive market, corporations have learned that taking sustainability issues into account can significantly improve their public image. Modern producers therefore must simultaneously reduce the environmental impact of their products and make economic gains. Therefore, making trade-offs between economic and environmental issues is required to ensure a company’s continuity. In doing so, companies have attached a great deal of importance to the new product design phase. However, optimization at the design stage becomes very complex for a product with a large number of parts, which can have several design alternatives with similar forms and functionality, but different costs and environmental impacts. In the automobile, shipbuilding and aircraft industries, if the conventional complete enumeration method is applied, the time required for selecting the optimal combination of design alternatives with respect to life cycle cost and environmental impact may exceed a human’s natural life span. To overcome this limitation, this paper introduces an optimization method for use as a design aid tool that enables a designer to assess the life cycle cost and environmental impact of his/her design very early in the product development process. To support the developed method, an illustration is provided using a case study on a locally manufactured automobile. 相似文献
946.
Ruth?WaldickEmail author Livia?Bizikova Denis?White Kathryn?Lindsay 《Regional Environmental Change》2017,17(1):187-200
The amount of information required to adapt to climate change is vast: downscaled climate projections, information on environmental impact, sectoral performance, external drivers, regional strategies, policies and practices. It can be argued that most of this information is accessible at the community/regional level, and thus, the important challenges to adaptation are not information gaps, but constraints created by fragmented planning decisions and a sector-by-sector basis for financial and human resource allocations. To strategically address this through adaptation planning, we developed and tested a place-based decision-making framework that creates an integrated platform for considering regional and global sectoral drivers in Eastern Ontario, Canada. Using available socioeconomic and biophysical information from regional authorities, alternative future scenarios were used to describe the range of socioeconomic futures and their vulnerabilities to climate change. We found that: (1) integration of diverse sets of available data (rather than narrowly focused sectoral assessments) helped identify shared common objectives (maximizing the long-term environmental, economic, social well-being within the region), (2) a high degree of congruence existed as the key drivers of change, irrespective of sector, (3) exploring the future scenarios highlighted shared regional priorities and helped identify adaptation priorities requiring more integrated regional planning. 相似文献
947.
Devendra?S.?WagareEmail authorView authors OrcID profile Prashant?D.?Netankar Mujahed?Shaikh Mazahar?Farooqui Ayesha?Durrani 《Environmental Chemistry Letters》2017,15(3):475-479
The thiazole ring system is one of the most important heterocycles in nature, as it represents an important structural motif of many biological compounds, including vitamin B1 (Thiamin), carboxylase and penicillin. There is, therefore, an urgent need to design rapid, efficient and environmentally benign protocols for the synthesis of thiazoles. Herein, we have developed a one-pot protocol for the synthesis of 4-aryl-2-aminothiazoles from the reaction of aromatic ketones, NBS (N-Bromosuccinimide) and thioureas under microwave irradiation at 80–85 °C in PEG (polyethylene glycol)-400 and water as a green reaction medium. The products were obtained in 84–89% yields in 28–32 min. The method has several advantages such as use of green solvent, easy work-up, excellent yield and avoiding use of lachrymatric α-haloketones. 相似文献
948.
Jeyaraj?PandiarajanEmail author Muthukalingan?Krishnan 《Environmental Chemistry Letters》2017,15(3):387-397
Silver nanoparticles are actually used in several industrial sectors and end up in the environment, thus inducing a possible toxicity for living organisms. This article reviews the properties, synthesis and toxicology of silver nanoparticles, with focus on the toxicity for insects such as Bombyx mori. 相似文献
949.
Quentin?Rendu Emmanuel?MignotEmail authorView authors OrcID profile Nicolas?Riviere Barbara?Lamberti-Raverot Sara?Puijalon Florence?Piola 《Environmental Fluid Mechanics》2017,17(5):1051-1065
Seed and fruit dispersal along watercourses favours the long-distance migration of invasive species, not only for aquatic or wetland species, but also for terrestrial wind-dispersed plants, like the Japanese knotweed. The present paper aims at investigating the role of watercourses in the dispersal of the knotweed due to its frequent occurrence on riverbanks and production of fertile achenes (type of fruit of the Japanese knotweed). This dispersal occurs along two steps after the fruits deposit on the water surface: floatation first and then sinking towards the bottom of the watercourse. Regarding the first step, the effects of agitation of the water, temperature, surface tension and luminosity on the achenes floatability are experimentally studied. While no influence of luminosity is observed, an increase of temperature greatly decreases the floating time. Floating time also decreases as the contact between water and the fruit is enhanced (through submersion of achenes, agitation of the water or lower surface tension). Regarding the second step, the fall velocity of the fruits in water at rest is measured and appears to be independent of the seed history (floating time). 3D helical motions are systematically observed with constant tangential velocity with respect to the falling velocity. The trajectory of the fruits in a shear flow is then measured and the evolution of their velocity components along the sinking process is discussed. Finally, the contribution of both steps to the long-distance migration of the seeds is estimated. 相似文献
950.
The flow structure in the aerated region of the roller generated by breaking waves remains a great challenge to study, with large quantities of entrained air and turbulence interactions making it very difficult to investigate in details. A number of analogies were proposed between breaking waves in deep or shallow water, tidal bores and hydraulic jumps. Many numerical models used to simulate waves in the surf zone do not implicitly simulate the breaking process of the waves, but are required to parameterise the wave-breaking effects, thus relying on experimental data. Analogies are also assumed to quantify the roller dynamics and the energy dissipation. The scope of this paper is to review the different analogies proposed in the literature and to discuss current practices. A thorough survey is offered and a discussion is developed an aimed at improving the use of possible breaking proxies. The most recent data are revisited and scrutinised for the use of most advanced numerical models to educe the surf zone hydrodynamics. In particular, the roller dynamics and geometrical characteristics are discussed. An open discussion is proposed to explore the actual practices and propose perspectives based on the most appropriate analogy, namely the tidal bore. 相似文献