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Given the concern about biodiversity loss, there are a number of arguments used for biodiversity conservation ranging from those emphasising the intrinsic value of biodiversity to those on the direct use value of ecosystems. Yet arguing the case for biodiversity conservation effectively requires an understanding of why people value biodiversity. We used Q methodology to explore and understand how different conservation practitioners (social and natural science researchers, environmental non-Governmental organisations and decision-makers) in nine European countries argue for conservation. We found that there was a plurality of views about biodiversity and its conservation. A moral argument and some arguments around the intrinsic and ecological value of biodiversity were held by all stakeholder groups. They also shared the view that species valuation does not justify the destruction of nature. However, there were also some differences within and between the groups, which primarily reflected the espousal of either ecocentric or anthropocentric viewpoints. Our findings suggest that moral arguments and those around biodiversity’s intrinsic and ecological value could potentially serve as a starting point for building consensus among conservation practitioners.  相似文献   

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Because of an increasing demand for animal-source foods, an increasing desire to reduce poverty and an increasing need to reduce the environmental impact of livestock production, tropical farming systems with livestock must increase their productivity. An important share of the global human and livestock populations are found within smallholder mixed-crop–livestock systems, which should, therefore, contribute significantly towards this increase in livestock production. The present paper argues that increased livestock production in smallholder mixed-crop–livestock systems faces many constraints at the level of the farm and the value chain. The present paper aims to describe and explain the impact of increased production from the farm and farmers’ perspective, in order to understand the constraints for increased livestock production. A framework is presented that links farming systems to livestock value chains. It is concluded that farming systems that pass from subsistence to commercial livestock production will: (1) shift from rural to urban markets; (2) become part of a different value chain (with lower prices, higher demands for product quality and increased competition from peri-urban producers and imports); and (3) have to face changes in within-farm mechanisms and crop–livestock relationships. A model study showed that feed limitation, which is common in tropical farming systems with livestock, implies that maximum herd output is achieved with small herd sizes, leaving low-quality feeds unutilised. Maximal herd output is not achieved at maximal individual animal output. Having more animals than required for optimal production – which is often the case as a larger herd size supports non-production functions of livestock, such as manure production, draught, traction and capital storage – goes at the expense of animal-source food output. Improving low-quality feeds by treatment allows keeping more animals while maintaining the same level of production. Ruminant methane emission per kg of milk produced is mainly determined by the level of milk production per cow. Part of the methane emissions, however, should be attributed to the non-production functions of ruminants. It was concluded that understanding the farm and farmers’ perceptions of increased production helps with the understanding of productivity increase constraints and adds information to that reported in the literature at the level of technology, markets and institutions.  相似文献   

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Despite widely acknowledged handicaps of the species approach to identifying priority conservation areas, many workers continue to use these flawed techniques as the backbone of their analyses. Species-based approaches address only a small part of biological diversity by ignoring different levels of organisation as well as the functional linkages among these levels. These data are often biased and incomplete and are often used in preference to data dealing with higher biological levels of organisation though the latter may be readily available. Within the framework of Noss's [(1990) Conservation Biology 4: 355–364] hierarchical definition of biodiversity (and Scott etal. [(1993) Wildlife Monographs 123: 1–31] gap analysis), we propose a top-down model dealing with broad organisational levels first, and finer-scale species distributions last. Note that we do not discard the latter approach, but merely argue for its use at a stage when, in our opinion, it adds most to the value of the prioritisation exercise. The model is flexible so that additional information, particularly those related to threats to biological diversity, can be added when they are available.  相似文献   

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Six regions of northwestern (NW) Baja California (Sierra de Juárez, Sierra de San Pedro Mártir, Punta Banda, Colonet, San Quintín and Valle Tranquilo) were compared for their floristic diversity. Checklists for each region were analyzed by their total, native, and endemic floras to give measures of floristic similarity and overlap, and to identify the strongest gradients affecting species distributions. Each region was floristically distinct, with significant variation in the distribution of state endemic taxa. The six regions are readily differentiated by their geographical position in a Principal Components Analysis. The strongest gradients were (a) the W–E gradient from the coast to the mountains and (b) the latitudinal gradient from N to S. These six adjacent regions are found within a local and global biodiversity hotspot that is subject to intense conservation challenges. Conservation of many areas is essential to adequately preserve the diversity of locally endemic taxa with restricted ranges, yet the coast lacks any protected areas at the state and federal level. Private reserves such as Reserva Natural San Quintín may be critical to the conservation of regionally endemic taxa.  相似文献   

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The expertise and knowledge of veterinary advisors on improving animal health management is key towards a better herd health status. However, veterinary advisors are not always aware of the goals and priorities of dairy farmers. To dairy farmers animal health is only one aspect of farm management and resources may be allocated to other more preferred areas. Veterinary advisors may experience this as non-compliant with their advice. To explore the preferences of European Union (EU) organic dairy farmers for improved animal health management relative to other farm management areas an adaptive conjoint analysis (ACA) was performed. A total of 215 farmers participated originating from organic dairy farms in France (n=70), Germany (n=60), Spain (n=28) and Sweden (n=57). The management areas udder health and claw health represented animal health management whereas barn, calf and pasture management represented potential conflicting management areas. Results indicate that EU organic dairy farmers differ in their preferences for improved animal health management within the farming system. In general, improved calf management was the most preferred area and improved claw health management was found to be least preferred, the remaining areas were of intermediate interest. Cluster analyses on claw health measures and udder health measures resulted in respectively seven and nine distinct preference profiles. The results indicate a high degree of variation in farmers’ preference, which cannot be explained by the typical herd characteristics. With the individual preferences revealed by ACA, a veterinary advisor can now find out whether his intended advice is directed at a favourable or unfavourable management area of the farmer. If the latter is the case the veterinarian should first create awareness of the problem to the farmer. Insights in individual farmers preferences will allow veterinary advisors to better understand why farmers were incompliant with their advice and improve their advice by showing, for example, the potential benefits of their advice.  相似文献   

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Biodiversity conservation efforts in Europe have traditionally focused on farmland and open nature areas such as grasslands, heathlands and meadows, while little attention has been devoted to conservation actions in forest. Using detailed information on the geographical distribution of about 900 terrestrial species in Denmark we apply systematic conservation planning techniques to identify how to protect biodiversity at the lowest cost to society. The results suggest that conservation actions in forest should be given a higher priority. Thus, three to four times the number of forest species are protected per million € compared with species living in open land natural areas. Furthermore, a gap analysis finds the current designation of Natura 2000 and other protected areas is skewed toward open land natural areas, and insufficient to meet the conservation targets on forest species.  相似文献   

8.
China has a long history of deforestation and environmental degradation. Because China is also lacking biological reserves, off-reserve conservation is a major contributor to its conservation efforts. Off-reserve conservation in China is primarily being achieved within afforestation and low-intensity agriculture. We compare ant diversity of three habitats: Natural Forest, Disturbed Forest and Plantation, to assess the conservation potential of these multiple land uses. Natural Forest consistently had the greatest plot-level species richness of the three habitats, but this pattern was only statistically significant for arboreal ants. Functional group profiles showed that Specialist Predators were significantly more represented in Disturbed Forest, Opportunists were significantly more represented in one Plantation site, coupled with a lack of Subordinate Camponotini, and Generalised Myrmicinae were more represented in a second Plantation site coupled with a complete lack of Cryptic Species. Multivariate analysis revealed significant differences of ant species composition between habitats. Within IndVal analyses, 17 species were associated with Natural Forest and nine with Plantation. No species were associated with Disturbed Forest. Reforestation and low-intensity agriculture clearly provide habitat for many species, but will not necessarily substitute for undisturbed habitat for many other species, especially specialised species. China’s off-reserve conservation could be enhanced by developing a greater understanding of agricultural practices and reforestation techniques that promote species diversity, especially for uncommon, threatened and specialised species.  相似文献   

9.
Agricultural soils with too little soil organic matter (SOM) content are characterized by fertility problems. A number of authors have tried to specify threshold values for SOM content to indicate what is ‘too little’, ranging from 1 to 5%, below which yields may be affected. How much SOM content is sufficient, however, depends on a number of environmental factors. In addition, up to date farmers’ perceptions were not included when developing thresholds. Therefore, this study focuses on the following three objectives: (1) to identify a risk indicator on SOM deficiency based on environmental factors and agricultural land use; (2) to test the risk indicator using farmers’ perceptions and (3) to establish threshold values for SOM content based on farmers’ perceptions.For objective 1, literature was reviewed on effects of environmental factors and land use on SOM deficiency. Findings were combined into nine options for a risk indicator on SOM deficiency, mapped at European scale. For objective 2, a farm survey was done among 1452 arable farmers in five European countries (Belgium, Germany, Austria, Spain and Italy). Associations between perceived deficiency of SOM by farmers and environmental factors, land use and the risk indicator were investigated. For objective 3, farmers’ perceptions on SOM deficiency were related to the average SOM content of their fields.Mapping the risk indicator at European scale gives a high to very high risk of SOM deficiency for 7 to 37% of European agricultural land, mainly located in Southern and Eastern Europe. Of the farmers in our survey, 18% perceived a high to very high SOM deficiency. A weak correlation was found between the risk indicator and farmers’ perceptions of SOM deficiency (0.15-0.18, Spearman’s rank correlation). Stronger relations were found between separate environmental factors and perceived SOM deficiency. Apparently, having a more extreme environmental condition for one factor gives a higher chance of perceiving a deficiency of SOM than a combination of moderate environmental conditions. Based on farmers’ perceptions threshold intervals for SOM content were established (sand: 1.2–4.7%, loam: 0.6–2.6% and clay: 1.0–2.4%).If policies on SOM management want to include benefits for productive capacity, targeting areas with a relatively high risk of SOM deficiency, more extreme environmental conditions or with very low SOM contents (below the given threshold intervals) seems most promising.  相似文献   

10.
Agricultural intensification may result in important shifts in insect community composition and function, but this remains poorly explored. Studying how groups of species with shared traits respond to local and landscape scale land-use management can reveal mechanisms behind such observed impacts. We tested if ground beetles (Coleoptera: Carabidae) divided into trait groups based on body sizes, wing morphologies and dietary preferences respond differently to farming practise (organic and conventional), farming intensity (measured as yield) and landscape complexity (measured as the proportion of arable land within a 1,000 m radius) across Europe. We used data from 143 farms in five regions in northern and central Europe. Organic farms did not differ in abundance or richness of any trait group compared to conventional farms. As farm scale intensity (yield) increased, overall abundance of beetles decreased, but abundances of small and medium sized beetles, as well as that of wingless beetles, were unaffected. Overall species richness was not affected by yield, whereas consideration of traits revealed that phytophagous and omnivorous beetles were less species rich on farms with high yields. Increasing the proportion of arable land in the landscape increased overall beetle abundance. This was driven by an increase in omnivorous beetles. The total species richness was not affected by an increase in the proportion arable land, although the richness of wingless beetles was found to increase. Potential effects on ecosystem functioning need to be taken into account when designing schemes to maintain agricultural biodiversity, because species with different ecological traits respond differently to local management and landscape changes.  相似文献   

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The role of hormones in mammary gland development has been studied in detail using surgical and genetic models. These studies have indicated roles for estrogen in ductal elongation and terminal end bud formation. However, no comprehensive study has quantified how different doses of estrogen affect morphological parameters of mammary gland development. Additionally, comparisons between the estrogen-responsiveness of the mammary gland and uterus, the model organ for estrogen action are incomplete. In this study, immature mice were ovariectomized and implanted with osmotic pumps releasing one of eight doses of 17β-estradiol for 10 days. As expected from the classical uterotrophic assay, the uterus showed a monotonic dose–response curve for all measured endpoints. In contrast, the mammary gland showed a non-monotonic, inverted-U shaped response to estrogen with regard to morphometric parameters, and a monotonic response with regard to gene expression parameters. These results indicate that estrogen has opposing effects in mammary gland morphogenesis depending on estrogen dose, i.e. low to moderate doses induce terminal end bud formation and ductal elongation while higher doses inhibit these processes. This non-monotonic dose–response in the mammary gland may reflect complex interactions, where estrogen can act on multiple targets either as an agonist or antagonist.  相似文献   

13.
Because employer-sponsored health insurance (ESI) is experience rated, employers have an incentive to try to offset its cost by paying lower wages to employees who have greater medical expenditures. The existing evidence on this topic, however, illustrates only that ESI is associated with lower wages for groups of workers who are costlier to cover. In contrast, I use the variation provided by the Affordable Care Act's employer mandate to examine if differences in medical expenditures are passed on to workers at the individual level. My estimates rely on Medical Expenditure Panel Survey data in a dose response difference-in-difference framework that examines how wages change for workers with varying medical expenditures when they must soon be offered ESI. I find that each $1 difference in medical expenditures is associated with a $0.35 to $0.51 wage offset after the employer mandate's announcement wherever ESI must soon be offered to workers. Placebo analyses, focusing on workers whose employers are not affected by the mandate, provide support for a causal interpretation. I also show that my findings are not sensitive to sample selection or data reliability issues and that they cannot be explained by the effects of the Great Recession, demographic characteristics that correlate with medical expenditures, or location- or industry-specific idiosyncratic shocks.  相似文献   

14.
Temperate grasslands have suffered disproportionally from conversion to cropland, degradation and fragmentation. A large proportion of the world’s remaining near-natural grassland is situated in Kazakhstan. We aimed to assess current and emerging threats to steppe and semi-desert biodiversity in Kazakhstan and evaluate conservation research priorities. We conducted a horizon-scanning exercise among conservationists from academia and practice. We first compiled a list of 45 potential threats. These were then ranked by the survey participants according to their perceived severity, the need for research on them, and their novelty. The highest-ranked threats were related to changes in land use (leading to habitat loss and deterioration), direct persecution of wildlife, and rapid infrastructure development due to economic and population growth. Research needs were identified largely in the same areas, and the mean scores of threat severity and research need were highly correlated. Novel threats comprised habitat loss by photovoltaic and wind power stations, climate change and changes in agriculture such as the introduction of biofuels. However, novelty was not correlated with threat severity or research priority, suggesting that the most severe threats are the established ones. Important goals towards more effective steppe and semi-desert conservation in Kazakhstan include more cross-sector collaboration (e.g. by involving stakeholders in conservation and agriculture), greater allocation of funds to under-staffed areas (e.g. protected area management), better representativeness and complementarity in the protected area system and enhanced data collection for wildlife monitoring and threat assessments (including the use of citizen-science databases).  相似文献   

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We currently have a meager understanding of the species attributes viewed as important for conservation by children, despite the fact that arguments for biodiversity conservation often hinge on the bequest value of species. We conducted a study of children between the ages of 4 and 14 (N = 183) on Andros Island, The Bahamas to determine how they prioritized wildlife species for conservation based on five attributes: endemism, use for hunting and fishing, rapid decline in population size, visibility around their home, and ecological significance. Children tended to rank ecological significance as the most important attribute for prioritizing wildlife for protection, followed closely by endemism, with other attributes being less important and not significantly different from one another. However, participants in a local environmental education program (N = 67) placed greater prioritization to species experiencing rapid population declines. We also found that boys prioritized use for hunting and fishing as more important for conservation than girls, older children placed greater importance on species with declining numbers and less importance on visibility of animals around their house, and children who had previously fished placed greater importance on endemism. These findings help elucidate how children value biodiversity, and suggest children’s conservation priorities may align relatively well with those of conservation biologists, especially after exposure to environmental education. We suggest that better understanding how children prioritize wildlife attributes for conservation can lead to more informed biodiversity conservation decisions and more effective policy implementation, as the perspectives of children can help bridge the gap between public opinion and scientific opinion.  相似文献   

17.
Spike length (SL), spikelet number (SPN) per spike, kernel number per spike (KNPS), and thousand-kernel weight (TKW) have strong genetic associations with kernel weight per spike (KWPS) in wheat. To investigate their genetic relationships at the individual quantitative trait locus (QTL) level, both unconditional and conditional QTL mapping for KWPS with respect to SL, SPN, KNPS, and TKW were conducted. Two related F8:9 recombinant inbred line populations, comprising 485 and 229 lines, respectively, were used. The trait phenotypic performances of each population were evaluated in four different environments. Unconditional QTL mapping analysis identified 22 putative additive QTL for KWPS, five of which were stable QTL, and only QKwps-WJ-1B.2 showed significant additive-by-environment interaction effects. In comparison with unconditional QTL mapping analysis, conditional QTL mapping analysis indicated that, at the QTL level, KNPS and TKW contributed more to KWPS than did SL and SPN. Any unconditional QTL for KWPS detected in this study was associated with at least one of its four related traits. The present study will provide assistance in the understanding of the genetic relationships between KWPS and its related traits.  相似文献   

18.
In the UK, the pig industry is leading the way in the adoption of welfare outcome measures as part of their farm assurance scheme. The welfare outcome assessment (WOA), known as Real Welfare, is conducted by the farmers’ own veterinary surgeon. For the first time, this has allowed the pig industry to evaluate welfare by directly assessing the animal itself and to document the welfare of the UK pig industry as a whole. Farmer perspectives of the addition of a welfare outcome assessment to their farm assurance scheme have yet to be explored. Here, we investigate how the introduction of the Real Welfare protocol has been perceived by the farmers involved, what value it has (if any), whether any practical changes on farm have been a direct consequence of Real Welfare and ultimately whether they consider that the welfare of their pigs has been improved by the introduction of the Real Welfare protocol. Semi-structured interviews with 15 English pig farmers were conducted to explore their perceptions and experiences of the Real Welfare process. Our findings fall into three key areas: the lived experience of Real Welfare, on-farm changes resulting from Real Welfare and suggested improvements to the Real Welfare process as it currently stands. In all the three areas, the value farmers placed on the addition of WOA appeared to reflect their veterinary surgeon’s attitude towards the Real Welfare protocol. If the vet was engaged in the process and actively included the farmer, for example through discussion of their findings, the farmers interviewed had a greater appreciation of the benefits of Real Welfare themselves. It is recommended that future similar schemes should work with veterinary surgeons to ensure their understanding and engagement with the process, as well as identifying and promoting how the scheme will practically benefit individual farmers rather than assuming that they will be motivated to engage for the good of the industry alone. Retailers should be encouraged to use Real Welfare as a marketing tool for pig products to enhance the perceived commercial value of this protocol to farmers.  相似文献   

19.

Background

Cowpeas are important staple legumes among the rural poor in northern Ghana. Our objectives were to assess the iron and zinc content of cowpea landraces and identify factors that predict the intention of mothers/caregivers to give cowpeas to their schoolchildren.

Methods and Findings

We performed biochemical analysis on 14 landraces of cowpeas and assessed the opinion of 120 caregiver-child pairs on constructs based on the combined model of the Theory of Planned Behaviour and Health Belief Model. We used correlations and multiple regressions to measure simple associations between constructs and identify predictive constructs. Cowpea landraces contained iron and zinc in the range of 4.9–8.2 mg/100 g d.w and 2.7–4.1 mg/100 g d.w respectively. The landraces also contained high amounts of phytate (477–1110 mg/100 g d.w) and polyphenol (327–1055 mg/100 g d.w). Intention of mothers was strongly associated (rs = 0.72, P<0.001) with and predicted (β = 0.63, P<0.001) behaviour. The constructs, barriers (β = –0.42, P = 0.001) and attitudes towards behaviour (β = 0.25, P<0.028), significantly predicted intention albeit the predictive ability of the model was weak.

Conclusions

We conclude that some cowpea landraces from northern Ghana have appreciable amounts of iron and zinc but probably with poor bioavailability. Attitudes towards giving cowpeas and perception of barriers are important predictors of caregivers’ intention to give cowpeas to their schoolchildren. Finally our results suggest that increasing knowledge on nutritional benefits of cowpeas may increase health values caregivers hold for their children in support of giving cowpeas to schoolchildren.  相似文献   

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