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排序方式: 共有196条查询结果,搜索用时 31 毫秒
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Götz Schroth Peter Laderach Jan Dempewolf Stacy Philpott Jeremy Haggar Hallie Eakin Teresa Castillejos Jaime Garcia Moreno Lorena Soto Pinto Ricardo Hernandez Anton Eitzinger Julian Ramirez-Villegas 《Mitigation and Adaptation Strategies for Global Change》2009,14(7):605-625
The mountain chain of the Sierra Madre de Chiapas in southern Mexico is globally significant for its biodiversity and is one of the most important coffee production areas of Mexico. It provides water for several municipalities and its biosphere reserves are important tourist attractions. Much of the forest cover outside the core protected areas is in fact coffee grown under traditional forest shade. Unless this (agro)forest cover can be sustained, the biodiversity of the Sierra Madre and the environmental services it provides are at risk. We analyzed the threats to livelihoods and environment from climate change through crop suitability modeling based on downscaled climate scenarios for the period 2040 to 2069 (referred to as 2050s) and developed adaptation options through an expert workshop. Significant areas of forest and occasionally coffee are destroyed every year by wildfires, and this problem is bound to increase in a hotter and drier future climate. Widespread landslides and inundations, including on coffee farms, have recently been caused by hurricanes whose intensity is predicted to increase. A hotter climate with more irregular rainfall will be less favorable to the production of quality coffee and lower profitability may compel farmers to abandon shade coffee and expand other land uses of less biodiversity value, probably at the expense of forest. A comprehensive strategy to sustain the biodiversity, ecosystem services and livelihoods of the Sierra Madre in the face of climate change should include the promotion of biodiversity friendly coffee growing and processing practices including complex shade which can offer some hurricane protection and product diversification; payments for forest conservation and restoration from existing government programs complemented by private initiatives; diversification of income sources to mitigate risks associated with unstable environmental conditions and coffee markets; integrated fire management; development of markets that reward sustainable land use practices and forest conservation; crop insurance programs that are accessible to smallholders; and the strengthening of local capacity for adaptive resource management. 相似文献
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Breda Jakovac-Strajn Katarina Pavšič-Vrtač Igor Ujčič-Vrhovnik Anton Vengušt Gabrijela Tavčar-Kalcher 《毒物与环境化学》2013,95(8):1551-1563
This study was aimed at investigating the contamination of grains, which are grown and used for animal diets by Slovene farmers. A total of 107 samples were examined for mesofilic aerobic molds and yeasts. The leading contaminants among molds were from Fusarium spp., detected in 73 samples, mostly in maize (50). In accordance with the European Feed Microbiology Organisation criteria, 68% of all tested samples were of the quality level I, with normal microbiological flora, and 9% of samples were estimated as quality level IV and not suitable for animal feed. Using liquid and gas chromatography methods, the presence of various mycotoxins (expressed as 12% of moisture content) was found in 77% of all samples; mostly deoxynivalenol (71%) in concentration of 150–14,420 µg kg?1, followed by zearalenone (32%, 20–640 µg kg?1), fumonisin B1 (31%, 10–4863 µg kg?1), fumonisin B2 (22%, 10–1629 µg kg?1), while HT-2 and T-2 toxins were found in low concentration in two samples, and aflatoxin B1 and ochratoxin A in one sample. By statistical evaluation, significant positive correlations were noted between the presence of deoxynivalenol and zearalenone as well as between fumonisin B1 and B2. 相似文献
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C. Hoolohan A. Larkin C. McLachlan R. Falconer I. Soutar J. Suckling L. Varga I. Haltas A. Druckman D. Lumbroso M. Scott D. Gilmour R. Ledbetter S. McGrane C. Mitchell D. Yu 《Sustainability Science》2018,13(5):1415-1426
The water–energy–food (WEF) nexus has become a popular, and potentially powerful, frame through which to analyse interactions and interdependencies between these three systems. Though the case for transdisciplinary research in this space has been made, the extent of stakeholder engagement in research remains limited with stakeholders most commonly incorporated in research as end-users. Yet, stakeholders interact with nexus issues in a variety of ways, consequently there is much that collaboration might offer to develop nexus research and enhance its application. This paper outlines four aspects of nexus research and considers the value and potential challenges for transdisciplinary research in each. We focus on assessing and visualising nexus systems; understanding governance and capacity building; the importance of scale; and the implications of future change. The paper then proceeds to describe a novel mixed-method study that deeply integrates stakeholder knowledge with insights from multiple disciplines. We argue that mixed-method research designs—in this case orientated around a number of cases studies—are best suited to understanding and addressing real-world nexus challenges, with their inevitable complex, non-linear system characteristics. Moreover, integrating multiple forms of knowledge in the manner described in this paper enables research to assess the potential for, and processes of, scaling-up innovations in the nexus space, to contribute insights to policy and decision making. 相似文献
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This study evaluated yield production and changes in the patterns of functional growth analysis parameters of greenhouse-grown soybeans exposed to low concentrations of ozone (O3). Plants were exposed over a 113-day interval for 341 h to four concentrations of O3 (2.0, 4.6, 7.0 and 9.7 pphm O3) on an intermittent basis. Destructive harvests were periodically taken from all treatments to monitor plant response and to provide the basis for growth analysis techniques. Relative to the ambient greenhouse air control treatment (2.0 pphm O3), 7.0 and 9.7 pphm O3 typically reduced plant biomass accumulation, leaf area and expansion, relative growth rate, unit leaf rate, seeds per plant (35% reduction), and other yield components; however, the growth and yield parameters of the 4.6 pphm O3 treatment were often stimulated. With this one exception, O3 reduced soybean vegetative growth and altered the pattern of biomass partitioning. As a consequence, the soybean yields were also reduced. 相似文献
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Carbon consumption and nitrogen requirements were estimated for populations of the sandy beach bivalve Donax serra on nine beaches of the west coast of South Africa. Subtidal populations composed mainly of adult clams were responsible for
the bulk of standing stock (3538 g C m−1), annual carbon consumption (13 444 g C m−1 yr−1), faeces production (6478 g C m−1 yr−1 ) and nitrogen regeneration (2525 g N m−1 yr−1). Kelp detritus, bacteria and kelp consumers' faeces available in the water column surpass several times the carbon and nitrogen
requirements of intertidal and subtidal clam populations. Individual Donax serra pop ulations, in turn, may regenerate up to 3.2% of the total nitrogen requirements of all primary producers from kelp beds
and 14% of the requirements of phytoplankton. These high standing stocks of clams are presumably supported mainly by organic
matter originating from kelp which, in contrast to phytoplankton, is in constant supply and comprises the largest proportion
of the annual production of particulate organic matter on this coast. Wide and shallow continental shelves with gentle slopes
probably limit the penetration of upwelled waters to the nearshore waters, decreasing the influence of external inputs and
increasing the importance of internal flows of nutrients and carbon within the nearshore zone. In this context, sandy beaches,
rocky shores and kelp beds may be more closely interlinked compartments of a larger ecosystem encompassing the whole nearshore
than traditionally thought.
Received: 28 August 1996 / Accepted: 7 October 1996 相似文献