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The purposes of this paper are: (a) to describe a framework designed for multi-scale sustainability evaluation of Natural Resource Management Systems (NRMS), and (b) to illustrate its application for quantitative analysis using linear programming. The framework described here is intended to contribute to the operationalisation of the concept of sustainability by supporting the processes of design, evaluation and implementation of alternative NRMS at different scales. In this paper, Linear Programming is used for the quantitative analysis of indicators and their trade-offs; using a schematised example, the basic characteristics of the Multi-scale Multiple Goal Linear Programming (M-MGLP) method are described. In M-MGLP, indicators pertaining to different scales of analysis can be set as objectives or constraints for the optimisation. In this way, stakeholders interacting in a specific region can be made aware of the consequences of alternative NRMS in terms of the different indicators at the same scale and/or for indicators at other scales of analysis. The paper ends with a discussion of the main strengths and limitations of the framework and, specifically, of linear programming.  相似文献   
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印染行业清洁生产技术   总被引:3,自引:0,他引:3  
论述了目前印染行业水污染的现状及原因,指出调整产业结构、应用新工艺、大力提倡节约用水、清沽生产将是印染行业实现可持续发展的必由之路。  相似文献   
3.
Equality of feeding roles and the maintenance of monogamy in tree swallows   总被引:2,自引:0,他引:2  
Summary We investigated the division of labor in male and female tree swallows by measuring the rate of food delivery to nestlings at 36 nests. By observing natural nests and performing brood manipulations we found that males and females divided the feeding duties about equally and responded similarly to changes in brood size and age. Feeding rate was most highly correlated with brood mass. Manipulation and removal experiments showed that increased feeding rates could be elicited, but only for limited periods of time. Male and female tree swallows could only partially compensate in feeding nestlings when mates were removed. This, along with the higher mortality in enlarged broods and in those raised by single parents, indicates that both male and female are required to raise an entire brood to fledging. We argue that this requirement contributes to the absence of mate guarding and the maintenance of monogamy in the tree swallow.  相似文献   
4.
The processes of nutrient depletion and soil degradation that limit productivity of smallholder African farms are spatially heterogeneous. Causes of variability in soil fertility management at different scales of analysis are both biophysical and socio-economic. Such heterogeneity is categorised in this study, which quantifies its impact on nutrient flows and soil fertility status at region and farm scales, as a first step in identifying spatial and temporal niches for targeting of soil fertility management strategies and technologies. Transects for soil profile observation, participatory rural appraisal techniques and classical soil sampling and chemical analysis were sampled across 60 farms in three sub-locations (Emuhaia, Shinyalu, Aludeka), which together represent much of the variability found in the highlands of western Kenya. Five representative farm types were identified using socio-economic information and considering production activities, household objectives and the main constraints faced by farmers. Soil fertility management and nutrient resource flows were studied for each farm type and related to differences in soil fertility status at farm scale. Farm types 1 and 2 were the wealthiest; the former relied on off-farm income and farmed small pieces of land (0.6–1.1 ha) while the latter farmed relatively large land areas (1.6–3.8 ha) mainly with cash crops. The poorest farm type 5 also farmed small pieces of land (0.4–1.0 ha) but relied on low wages derived from working for wealthier farmers. Both farm types 1 and 5 relied on off-farm earnings and sold the least amounts of farm produce to the market, though the magnitude of their cash, labour and nutrient flows was contrasting. Farms of types 3 and 4 were intermediate in size and wealth, and represented different crop production strategies for self-consumption and the market. Average grain yields fluctuated around 1 t ha−1 year−1 for all farm types and sub-locations. Grain production by farms of types 4 and 5 was much below annual family requirements, estimated at 170 kg person−1 year−1. Household wealth and production orientation affected the pattern of resource flow at farm scale. In the land-constrained farms of type 1, mineral fertilisers were often used more intensively (ca. 50 kg ha−1), though with varying application rates (14–92 kg ha−1). The use of animal manure in such small farms (e.g. 2.2 t year−1) represented intensities of use of up to 8 t ha−1, and a net accumulation of C and macronutrients brought into the farm by livestock. In farms of type 5, intensities of use of mineral and organic fertilisers ranged between 0–12 kg ha−1 and 0–0.5 t ha−1, respectively. A consistent trend of decreasing input use from farm types 1–5 was generally observed, but nutrient resources and land management practices (e.g. fallow) differed enormously between sub-locations. Inputs of nutrients were almost nil in Aludeka farms. Both inherent soil properties and management explained the variability found in soil fertility status. Texture explained the variation observed in soil C and related total N between sub-locations, whereas P availability varied mainly between farm types as affected by input use.  相似文献   
5.
将时间-活动模式与微环境空气污染物监测相结合估计儿童个体NOx暴露水平. 分别在北京和青岛两市各选择3所学校监测校园环境污染物,并在每个学校选择10名儿童监测其家庭居室空气中ρ(NOx)及个体24 h NOx暴露水平,同时收集其时间-活动信息,采用时间-活动模式估计儿童的个体暴露水平. 交通工具中的NOx暴露水平可通过校门口空气中ρ(NOx)和交通工具的污染水平系数(λ)估计.结果表明:利用时间-活动模式模拟的儿童个体24 h NOx暴露水平为0.041 mg/m3,与调整后的个体暴露实测水平相关性较好(R0.785,P<0.01),差值为(-0.002 6±0.013 0) mg/m3,二者的差异无统计学意义 (t0.139,P>0.05).表明采用时间-活动模式与微环境空气质量监测结果相结合方法估计的儿童NOx暴露水平与个体实际暴露水平一致.   相似文献   
6.
Summary We monitored the time spent at the nest and following behavior of mated tree swallows to determine if males were guarding their mates. The proportion of time spent together at the nest did not decrease significantly between fertile and postfertile periods, and the tendency of males to follow females was not significantly different from that of females to follow males. Following by either sex was infrequent. We suggest that the lack of mate guarding in tree swallows is related to an apparently low probability of extra-pair copulations, which in turn is likely to be due to two factors. Nesting opportunities are limited, perhaps more so for females than males. If the operational sex ratio is skewed towards females, this would not only reduce the risk of extra-pair copulations, but would also select against promiscuous females which would risk being abandoned by their mates. Secondly, under natural conditions, the limited availability of nest sites has selected for territorial defense by both males and females, which may decrease the occurrence of extra-pair copulation. Both factors would lead to relaxed selection for mate guarding behavior.  相似文献   
7.
Design and implementation of more sustainable natural resource management systems is the current objective of many research institutions, development agencies, NGOs and other stakeholders. But, how to assess whether a system is sustainable? How do we know whether the alternatives designed will increase the sustainability of the system? How to evaluate or assess the sustainability of natural resource management systems?In this paper we present a multiscale methodological framework for sustainability evaluation. The framework is based on a systems approach from which five general attributes of sustainable natural resource management systems are defined based on scale- and discipline-independent properties (productivity, stability, resilience, reliability and adaptability).A general operational strategy to derive ‘site-specific’ criteria and indicators for the attributes at different scales is also presented. This strategy is based on the definition of ‘impact scales’, at which the different stakeholders can or want to design alternatives, as well as the main stakeholders’ objectives and constraints. The application of the multiscale framework is illustrated with a case study in the Purhepecha Region of Michoacán, a peasant mountainous region in the west of Mexico. We used stakeholder consultation to identify the main objectives and constraints as well as to select criteria and indicators. The sets of criteria and indicators suggested for the different scales of analysis of the Purhepecha Region are comprehensive, yet not exhaustive, and represent the main issues related to natural resource management in the region. Further work will be directed towards the quantification of indicators at different scales and their relationships and trade-offs.  相似文献   
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