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81.
In 2004–05, Niger suffered a food crisis during which global attention focused on high levels of acute malnutrition among children. In response, decentralised emergency nutrition programmes were introduced into much of southern Niger. Child malnutrition, however, is a chronic problem and its links with food production and household food security are complex. This qualitative, anthropological study investigates pathways by which children are rendered vulnerable in the context of a nutritional 'emergency'. It focuses on household-level decisions that determine resource allocation and childcare practices in order to explain why practices apparently detrimental to children's health persist. Risk aversion, the need to maintain self-identity and status, and constrained decision making result in a failure to invest extra necessary resources ingrowth-faltering children. Understanding and responding to the social context of child malnutrition will help humanitarian workers to integrate their efforts more effectively with longer-term development programmes aimed at improving livelihood security. 相似文献
82.
R. Peter Richards 《Journal of the American Water Resources Association》1989,25(4):891-904
ABSTRACT: Evaluation of the non-point source pollutant load entering a lake from multiple tributaries requires either that all tributaries be monitored or that some extrapolation method be used to estimate loads originating in areas not monitored. Unmonitored areas include not only watersheds of tributaries that are not monitored, but also portions of a monitored tributary's drainage basin downstream from the monitoring site and areas of direct drainage. Significant portions of large lake drainage basins are often not monitored, and loads for these areas are often estimated by extrapolation. Six simple extrapolation procedures were evaluated by using them to estimate loads for areas that had been monitored and comparing the estimated loads with the monitored loads. Three approaches were based on inter-basin ratios of area, C-factor, and discharge. The other approaches used regression relationships between concentration and flow to estimate concentrations for the unmonitored basin. The ratio approaches generally were more reliable than the regression approaches. However, extrapolation by any method tested was not very precise. Some methods also were biased when applied to watersheds of a size different than the monitored one. Extrapolation by any of these methods would compromise the precision of the lake-wide load estimate, if the unmonitored area were a significant part of the entire basin. 相似文献
83.
Kate Millar 《Journal of Agricultural and Environmental Ethics》2007,20(3):301-304
84.
Based on preliminary findings of ongoing 'action research' in the war zone in central Sierra Leone, this paper shows how more equitable seed distribution could contribute to fostering a culture of human rights as well as to agricultural rehabilitation. Assessment of seeds-and-toosl programmes in 19 villages found that aid agency targeting and distribution modalities channelled inputs through village committees which denied assistance to intended beneficiary groups. Such distribution inequalities constitute violations of fundamental human rights, exacerbate grievance and division and maintain the threat of social disorder. The benefits and disadvantages of an alternative, more inclusive, rights-based approach to seed distribution are discussed, and preliminary results from the pilot phase of CARE's Rights-based Approach to Food Security Project are presented. Under this project, village-level peace and rights days are held to allow villagers to debate the vulnerabilities that facilitated the war and to elaborate on local notions of human rights. In symbolising new beginnings, seed can be seen as a useful medium through which to debate a more inclusive--and ultimately less vulnerable--society. 相似文献
85.
Kate M. Millar 《Journal of Agricultural and Environmental Ethics》2000,12(1):41-50
An analysis of the ethical impacts of the use of anAutomatic Milking System (AMS) is employed as a casestudy to illustrate the use of a form of bioethicalanalysis in technology assessment. The approach isbased on the Ethical Matrix, where `impacts' areassessed in terms of (lack of) respect for threeethical principles as applied to interest groups. Inthis case, only impacts on dairy cows are examined,and principally in terms of their behaviouralfreedom.In contrast to traditional milking systems, AMS, inprinciple, allow cows to present for milkingvoluntarily. So with AMS, it is claimed that dairymanagement relies on the autonomous interaction of thecow with her environment.One of the roles of bioethical analysis is to identifythe influence of rhetoric and symbolism in technologyassessment, e.g., with respect to the claimed`voluntariness' of cows' presentation. The AMS can beinstalled to allow cows three types of access, viz., i)free choice ii) rewarded access (RA) iii) obligatoryaccess (OA). Studies suggest the desire for milkremoval per se is not critical in the cow'sattendance at the AMS. Continued motivation to bemilked, required for the system to function,principally relies on RA and OA. Both RA and OA aresubject to numerous factors, such as: design of theAMS, location, etc. In turn, these can affect thecows' behavioural freedom and welfare.One of the aims of this approach is to illustrate theethical basis on which public policy is or can beformulated. 相似文献
86.
Kate A. Rawlinson 《Marine Biology》2008,153(5):769-778
Polyclads are mobile predators and possibly an important functional component of hard substrate marine environments globally.
To understand the natural patterns of spatial differences, polyclad assemblages were sampled in seven coastal regions across
the wider Caribbean spanning 15° latitude and 24° longitude between May and June 2005 and May and September 2006. In total,
67 species in 28 genera and 17 families were recorded from 62 sites. Only two species were found in all surveyed regions,
Melloplana ferruginea and Pseudoceros bicolor. Conversely, 41 species were restricted to one or two sites, and 34 species were represented by one or two individuals. The
distribution and abundance of species varied between the two suborders. Cotyleans were most species rich and had a higher
number of species of restricted range, while Acotylea showed a higher proportion of rare species; however, two species were
highly abundant comprising over half of the individuals counted. In most habitats, polyclads were rare, but in some intertidal
habitats two species, Styloplanocera fasciata and Boninia divae were densely aggregated and dominant members of the benthic epifauna. Alpha diversity was variable but showed no evidence
of a relationship with latitude, longitude or depth. Beta diversity increased with the number of habitats sampled and was
highest for cotyleans. Highest gamma diversity was recorded in Jamaica and the US Virgin Islands and was not significantly
correlated to alpha diversity. Overall assemblages from the seven regions were similar, revealing faunal homogeneity across
the wider region. Reef assemblages were distinct from other habitats dominated by species of the Cotylea. Reefs from Panama
and the US Virgin Islands were the most species rich.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
87.
88.
Pair-wise preference experiments were used to reveal predator discrimination by four tit species wintering in the Czech Republic.
The reactions of the tits to a more dangerous predator (sparrowhawk) and a less dangerous (kestrel) one were compared. The
number of visits to a feeder with a predator present expressed the perceived dangerousness of the predator. The tits' behaviour
towards the feeders was in agreement with predictions, according to dynamic risk assessment theory. The presence of any predator
at the feeder lowered the number of visits to the feeder. Similarly, the tits were judged to have evaluated the sparrowhawk
as being more dangerous than the kestrel, as its presence lowered the number of arrivals more than did the kestrel. The duration
of stay and number of pecks of individual birds were also used as measures of predator dangerousness. The results not only
confirm that tits behave according to dynamic risk assessment theory, but also show the exceptional suitability of preference
experiments for the research of predator differentiation and evaluation. 相似文献
89.
Harris KA Yunker MB Dangerfield N Ross PS 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2665-2674
Sediment-associated hydrocarbons can pose a risk to wildlife that rely on benthic marine food webs. We measured hydrocarbons in sediments from the habitat of protected sea otters in coastal British Columbia, Canada. Alkane concentrations were dominated by higher odd-chain n-alkanes at all sites, indicating terrestrial plant inputs. While remote sites were dominated by petrogenic polycyclic aromatic hydrocarbons (PAHs), small harbour sites within sea otter habitat and sites from an urban reference area reflected weathered petroleum and biomass and fossil fuel combustion. The partitioning of hydrocarbons between sediments and adjacent food webs provides an important exposure route for sea otters, as they consume ∼25% of their body weight per day in benthic invertebrates. Thus, exceedences of PAH sediment quality guidelines designed to protect aquatic biota at 20% of the sites in sea otter habitat suggest that sea otters are vulnerable to hydrocarbon contamination even in the absence of catastrophic oil spills. 相似文献
90.
Synthetic fibers as an indicator of land application of sludge 总被引:6,自引:0,他引:6
Synthetic fabric fibers have been proposed as indicators of past spreading of wastewater sludge. Synthetic fiber detectability was examined in sludges (dewatered, pelletized, composted, alkaline-stabilized) and in soils from experimental columns and field sites applied with those sludge products. Fibers (isolated by water extraction and examined using polarized light microscopy) were detectable in sludge products and in soil columns over 5 years after application, retaining characteristics observed in the applied sludge. Concentrations mirrored (within a factor of 2) predictions based on soil dilution. Fibers were detectable in field site soils up to 15 years after application, again retaining the characteristics seen in sludge products. Concentrations correlated with residual sludge metal concentration gradients in a well-characterized field site. Fibers found along preferential flow paths and/or in horizons largely below the mixed layer suggest some potential for translocation. Synthetic fibers were shown to be rapid and semi-quantitative indicators of past sludge application. 相似文献