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1.
Environmental assessment methods are needed by agronomists working on the enhancement of cropping systems to meet the demand for more sustainable farming practices. A growing number of operational methods based on a set of indicators have been designed, more for arable crops and livestock than for perennial crops like viticulture. Among them, the INDIGO® method, originally developed for arable crops, offers a compromise between feasibility and predictive quality. Here we present a modified and expanded version of INDIGO® for viticulture. The development of new indicators specific to viticulture and the adaptation of existing ones followed a five step approach: (i) preliminary definition of the objectives and identification of the end-users, (ii) construction of the indicator, (iii) selection of a reference value, (iv) sensitivity analysis and (v) validation. Stakeholders from professional institutions and winegrower organizations were closely associated with step (i) to define the framework and step (ii) to supply technical databases. We designed INDIGO® indicators with all available scientific and expert knowledge which was aggregated into expert systems associating fuzzy subsets or, when possible, quantitative equations.Four indicators; pesticides, nitrogen, energy and soil organic matter, were directly adapted from the initial INDIGO® method, whereas soil cover and frost protection management were new indicators. Potentialities of their use are highlighted by examples of implementation on different scales and for various purposes.  相似文献   
2.
Sheep production is the main agricultural activity in Patagonia. Since the middle of the 20th century, sheep numbers have declined steadly. We used historical records of stock numbers in four ranches to analyze the importance of regional factors so as to explain the decline of the Patagonian sheep flocks. We found that the stocks of all the four ranches declined with a similar trend but fluctuated independently, thus reflecting a complex interaction between regional and local factors. Aboveground net primary production (ANPP) and vegetation physiognomy explained most of the differences in the flocks declining rates. We estimated demographic parameters for two ranches differing in their average annual growth rates. From these demographic parameters, we constructed deterministic and stochastic matrix models to establish the relative contribution of demographic processes to the observed decline. Matrix models projected a faster decline than that observed in the ranch used to calibrate the model. This suggests that the recorded demographic parameters could drive most stocks to extinction in less than 100 years. We concluded that the observed dynamics would be generated by demographic processes, but extinction is delayed or avoided by a continuous intake of animals. Ewe survival was the most important parameter in controlling the growth rate of the flocks. The environmental stochastic model showed that the growth of the stocks was highly sensitive to increases in the frequency of good years (those that produce a positive growth) and in the transition from normal years to bad years. All these evidences point out the existence of biological constraints to sheep production in Patagonia: ANPP and vegetation structure would control flock population dynamics throughout its effects on key demographic parameters, ewe survival and marking rate (a recruitment measure). Our model results suggest that the decline in sheep numbers, and hence the sustainability of the activity, is driven, to a large extent, by the demographic characteristics of the flocks.  相似文献   
3.
This paper evaluates the resource and energy requirements of six different types of land-based, hatchery production systems located in the U.S. Pacific Northwest: flow-through with a gravity water supply, flow-through with a pumped water supply, flow-through with pure oxygen, partial reuse system, partial reuse with heating, and a reuse system for the production of Atlantic salmon (Salmo salar) smolts. Key parameters used in the evaluation include direct energy, indirect energy, transportation energy, greenhouse gas emissions, and pollutant discharges.Power (electricity and natural gas) and feed energy accounted for the majority of the required energy for all the rearing option evaluated. The sum of the fixed capital and chemicals components accounted for less than 2–12% of the total energy budget for any rearing option. The energy efficiency (energy output/energy input) of the six options ranges from 0.97% for flow-through with pumped supply to 3.49% for the flow-through with gravity supply. The rearing options with the three highest energy efficiencies were flow-through with gravity supply (3.49%), partial reuse (2.75%), and reuse (2.64%).On a kg of smolt produced basis, the six rearing options showed a wide range in performance. The reuse system had the lowest water (2 m3 kg− 1) and land (0.13 m2 kg− 1) requirements and the third lowest total energy requirement (288 MJ kg− 1). The partial reuse system had the second lowest total power requirement (276 MJ kg− 1), a low land requirement (0.21 m2 kg− 1), and moderate water requirements (33 m3 kg− 1). The partial reuse with temperature control had the second highest total power requirement (657 MJ kg− 1) and land and water requirements similar to the partial reuse system without temperature control. The flow-through system with pumped water supply had the highest water (289 m3 kg− 1), land (2.19 m2 kg− 1), and energy requirements (786 MJ kg− 1) of any of the rearing options. By comparison, the flow-through system with gravity water supply had the lowest energy requirement (218 MJ kg− 1), a moderate land requirement (0.78 m2 kg− 1), and a high water requirement (214 m3 kg− 1). The ranking of the six rearing options based capital and operating costs are likely to be quite different from those based on energy, water, and greenhouse gas emissions.  相似文献   
4.
Although the linkages between economics and environment are absolute, they are not emphasized either by the economic or by the environmental professions. The economics of natural resources remains a minor unpopular theme in orthodox economics today. Similarly, the relationship of the economic subsystem to the overall ecosystem is only mentioned in most environmental science texts. Attention to the environmental dimensions of economic development burgeoned in the early 1970s and has yet to become systematic. There are encouraging signs that this is improving. The integration of economics and environmental studies has been the focus of several recent conferences and books, e.g. Brundtland, 1987; Conway, 1985; IIED, 1987; Jansson, 1984; Pearce, 1985 and at least two journals (Environmental Economics from 1976, and Ecology and Economics from 1987; excluding the vast literature mainly on pollution economics. This paper mentions four environmental aspects of economic development: the concept of sustainability, carrying capacity, ethics and irreversibility. It then focuses on one important irreversible—the loss of biodiversity—and outlines progress with the World Bank's policies in this regard.  相似文献   
5.
食品安全内涵及评价指标体系研究   总被引:15,自引:0,他引:15  
食品安全问题是一个国家经济持续稳定发展的基础,是社会稳定与繁荣的保证.食品安全包括食品数量安全、食品质量安全和食品可持续安全.中国食品安全综合水平处于安全状态,食品安全综合指数为0.551,但仍是较低水平的安全.  相似文献   
6.
在云南省绿春县的有些村庄,由砍柴造成的森林破坏是造成环境退化的主要原因。在黑河流域的上游,不断加剧的水土流失和河床抬升对下游上百万的人们构成威胁。尽管人们对森林破坏和土地的可持续利用、社区可持续发展之间的关系不是不了解,但当生存压力存在的时候就会忽略由此造成的对未来的影响。对于村民来说,他们已经意识到了他们的生存状况,并讨论解决的有效途径,而不是单纯等待外界的援助和干预。问题的关键是如何将这些变化和影响以一种直观和形象的方式向村民解释,并且让包括文盲在内的所有人都能理解。从这方面考虑,图形的东西比文字和数字分析更有优势。本文采用MIGIS(移动交互式地理信息系统的英文缩写,它包括两部分的内容,即PLA-参与式学习和行动和GIS-地理信息系统)在云南省绿春县哈尼族村寨来协助进行村民自发的造林规划。图6表1参16。  相似文献   
7.
Landings in the blue crab, Portunus trituberculatus, fishery in Korean waters of the Yellow Sea have declined substantially from 11,000 t in the 1980s to 2,300 t in 2004. Blue crab habitat quality in the Yellow Sea has been degraded by anthropogenic activities including sand mining, land reclamation, and coastal pollution. Various traditional management measures have been implemented, including closed seasons during spawning and size limits, but these measures alone have been unsuccessful to conserve blue crab stocks. Consequently, a total allowable catch and a stock-rebuilding program using an ecosystem-based management approach were implemented in 2003 and 2006, respectively to rebuild blue crab stocks and restore habitats. This program involved assessment of both blue crab stock status and trammel-net fishery impacts at an ecosystem-level using an ecosystem-based fisheries assessment method ( [Zhang et al., 2009] and [Zhang et al., 2010]), which considered fishery data from catch and effort time-series, crab population biology, and ecosystem characteristics, including habitats and environmental conditions. Recent (2008) management status indices have shown significant positive change compared to conditions in 2000 with respect to sustainability of the stock and fishery and with regards to biodiversity and ecosystem habitat quality.  相似文献   
8.
This investigation aims to classify, describe and evaluate the sustainability of dairy goat production systems (GPS) in South Spain Sierra de Cadiz. The research took place throughout 25 goat farms during the 2001–2002 campaigns, with the method posed by Masera et al. (1999) [Masera, O., Astier, M., S., López-Ridaura. 1999. Sustentabilidad y manejo de recursos naturales. El marco de evaluación MESMIS (Sustainability and natural resource management. The MESMIS evaluation framework). Mundi-Prensa, S.A., Gira, IE-UNAM, México. 109 pp.] and adapted to animal production systems, as the guideline and framework to evaluate sustainability.

The principal component, namely energy input from grazing (eigenvalue 1.329) which comprises the indicators total area per goat (factorial value 0.664) together with net energy obtained from grazing (factorial value 0.903) allowed to differentiate significantly between semi extensive (SES), semi intensive (SIS) and intensive (IS) goat production systems.

Intensification of the GPS tends to be inefficient, especially in terms of net margin per litre of milk produced (p < 0.05). A higher degree of adaptability of IS (64.8%) derives from a higher investment on new production strategies. Likewise, higher self-management capacity of SES (60.9%) fosters standards of productivity (76.0%) and stability (42.9%). The SIS presented the highest equity values (67.8%).

On the whole, sustainability of GPS tends to decrease as the degree of intensification increases: SES = 57.3%; SIS = 55.7% and IS = 53.1%. The reduction of the dependency on external input alongside with the optimization of natural resources management would surely improve the standard of sustainability.  相似文献   

9.
Kayu putih oil, extracted from the kayu putih tree (Melaleuca leucadendron), is an important non-timber forest product (NTFP) in Indonesia. We compared productivity of kayu putih tree plantations among three different sites in East, Central, and West Java, Indonesia. Leaf-twig, and branch production per tree differed significantly among the three sites. Tree biomass production was highest at the site in West Java practicing tumpangsari (a form of shifting cultivation) of kayu putih with rice (Oryza sativa) on alluvial soils. Tree biomass production was lowest at the site in East Java, practicing tumpangsari of kayu putih with maize (Zea mays) and cassava (Mani- hot esculenta). At this site, tree biomass production increased with increasing stand age and low production was compensated by greater biomass yield of companion crops. Intermediate tree biomass production was observed at the site in Central Java where intercropping is only practiced for the first two years after plantation establishment. Production of tree biomass and kayu putih oil did not increase with increasing stand density, indicating that at a given site, high tree stocking did not lead to high production. Stand-level productivity of the plantations increased with increasing stand age and maximum productivity was attained at 15 to 35 years, after which productivity declined. This suggested unsustainable stand productivity as plantations increase in age.  相似文献   
10.
Aquaculture has been the world's fastestgrowing source of food, with fin fish andshellfish production expanding by an averagecompound rate of growth of 10.9%. This is arate of growth faster than that of terrestrialmeat production. The paper describes policiesthat can promote aquaculture. The focus is oncommercial (for profit) aquaculture, butsubsistence aquaculture is indirectly includedon the assumption that the two systems arecomplementary, rather than mutuallyexclusive.  相似文献   
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