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11.
Attitude data from a national sample of 2300 working adults are reported. The data show that employees feel they should have more influence on a number of decisions. This feeling is stronger for decisions affecting how their job is done, than for matters of corporate policy and personnel decisions. However, it is in the policy and personnel areas that they perceive the greatest discrepancy between the amount of influence they presently have and the amount of influence they feel they should have. Older, better educated, and higher-paid respondents felt they should have more influence on all decisions. The implications of these findings for the Quality of Work Life movement were considered. The data suggest a favourable future climate for certain types of employee influence/Quality of Work Life projects. 相似文献
12.
Genetic variation in defense chemistry in wild cabbages affects herbivores and their endoparasitoids 总被引:2,自引:0,他引:2
Gols R Wagenaar R Bukovinszky T van Dam NM Dicke M Bullock JM Harvey JA 《Ecology》2008,89(6):1616-1626
Populations of wild Brassica oleracea L. grow naturally along the Atlantic coastlines of the United Kingdom and France. Over a very small spatial scale (i.e., <15 km) these populations differ in the expression of the defensive compounds, glucosinolates (GS). Thus far, very few studies have examined interactions between genetically distinct populations of a wild plant species and associated consumers in a multitrophic framework. Here, we compared the development of a specialist (Pieris rapae) and a generalist (Mamestra brassicae) insect herbivore and their endoparasitoids (Cotesia rubecula and Microplitis mediator, respectively) on three wild populations and one cultivar of B. oleracea under controlled greenhouse conditions. Herbivore performance was differentially affected by the plant population on which they were reared. Plant population influenced only development time and pupal mass in P. rapae, whereas plant population also had a dramatic effect on survival of M. brassicae. Prolonged development time in P. rapae corresponded with high levels of the indole GS, neoglucobrassicin, whereas reduced survival in M. brassicae coincided with high levels of the aliphatic GS, gluconapin and sinigrin. The difference between the two species can be explained by the fact that the specialist P. rapae is adapted to feed on plants containing GS and has evolved an effective detoxification system against aliphatic GS. The different B. oleracea populations also affected development of the endoparasitoids. Differences in food-plant quality for the hosts were reflected in adult size in C. rubecula and survival in M. mediator, and further showed that parasitoid performance is also affected by herbivore diet. 相似文献
13.
Understanding and Integrating Local Perceptions of Trees and Forests into Incentives for Sustainable Landscape Management 总被引:1,自引:0,他引:1
Pfund JL Watts JD Boissière M Boucard A Bullock RM Ekadinata A Dewi S Feintrenie L Levang P Rantala S Sheil D Sunderland T Sunderland TC Urech ZL 《Environmental management》2011,48(2):334-349
We examine five forested landscapes in Africa (Cameroon, Madagascar, and Tanzania) and Asia (Indonesia and Laos) at different stages of landscape change. In all five areas, forest cover (outside of protected areas) continues to decrease despite local people's recognition of the importance of forest products and services. After forest conversion, agroforestry systems and fallows provide multiple functions and valued products, and retain significant biodiversity. But there are indications that such land use is transitory, with gradual simplification and loss of complex agroforests and fallows as land use becomes increasingly individualistic and profit driven. In Indonesia and Tanzania, farmers favor monocultures (rubber and oil palm, and sugarcane, respectively) for their high financial returns, with these systems replacing existing complex agroforests. In the study sites in Madagascar and Laos, investments in agroforests and new crops remain rare, despite government attempts to eradicate swidden systems and their multifunctional fallows. We discuss approaches to assessing local values related to landscape cover and associated goods and services. We highlight discrepancies between individual and collective responses in characterizing land use tendencies, and discuss the effects of accessibility on land management. We conclude that a combination of social, economic, and spatially explicit assessment methods is necessary to inform land use planning. Furthermore, any efforts to modify current trends will require clear incentives, such as through carbon finance. We speculate on the nature of such incentive schemes and the possibility of rewarding the provision of ecosystem services at a landscape scale and in a socially equitable manner. 相似文献
14.
The European Environmental Liability Directive aims to ensure that damaged habitats are restored where possible, but allows for complementary remediation with replacement habitat where restoration is not possible within a reasonable time. It also allows for compensatory remediation of the resource based on an assessment of environmental values in cases where there are interim social losses. This paper concurs with the argument that physical remediation without consideration of social values can fail to be equivalent to the resource that has been lost. Using, as a case study, a river in Ireland, it demonstrates that estimating social value can be challenging in practice, noting also differences between the value of environmental gains and losses. The paper argues that estimates of final ecosystem service values, including wastewater treatment costs, can provide a measure of social value and makes a case for the systematic collection of these data to inform decision-making. 相似文献
15.
Dearing JA Bullock S Costanza R Dawson TP Edwards ME Poppy GM Smith GM 《Environmental management》2012,49(4):767-775
The ‘Perfect Storm’ metaphor describes a combination of events that causes a surprising or dramatic impact. It lends an evolutionary
perspective to how social-ecological interactions change. Thus, we argue that an improved understanding of how social-ecological
systems have evolved up to the present is necessary for the modelling, understanding and anticipation of current and future
social-ecological systems. Here we consider the implications of an evolutionary perspective for designing research approaches.
One desirable approach is the creation of multi-decadal records produced by integrating palaeoenvironmental, instrument and
documentary sources at multiple spatial scales. We also consider the potential for improved analytical and modelling approaches
by developing system dynamical, cellular and agent-based models, observing complex behaviour in social-ecological systems
against which to test systems dynamical theory, and drawing better lessons from history. Alongside these is the need to find
more appropriate ways to communicate complex systems, risk and uncertainty to the public and to policy-makers. 相似文献
16.
Seeing the world through a new sense: electroreception in fish 总被引:1,自引:0,他引:1
T H Bullock 《American scientist》1973,61(3):316-325
17.
Craig H. Bullock 《Journal of Environmental Planning and Management》2008,51(1):15-35
Although many cities have guidelines on the quantity of green open space that should accompany residential development, there is less guidance on the type or facilities of these spaces. The study uses an approach to determine whether green space can be valued on the basis of its constituent characteristics and, if so, what characteristics are preferred. The results indicate that preferences vary depending on whether the green space in question is a small local park or a larger municipal park. However, where a base alternative of usual park destination is included in the analysis, the results are affected by collinearity and the actual availability of relevant green space attributes in these destinations. A mixed logit approach is used to tease out this effect from the underlying preference values. 相似文献
18.
John J. Kalvinskas Wallace A. Moser Thomas E. Bullock 《Journal of the American Water Resources Association》1971,7(2):330-342
. Water Reservoir Systems were investigated for urban areas as an alternative or complement to storm water drainage systems for flood control which could provide benefits in water conservation and reduce drainage system costs. The study consisted of: (1) gathering of engineering data on the topographical, hydrological, and precipitation characteristics of the area and urban development and economic statistics 相似文献
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20.
Phosphorus runoff: effect of tillage and soil phosphorus levels 总被引:2,自引:0,他引:2
Daverede IC Kravchenko AN Hoeft RG Nafziger ED Bullock DG Warren JJ Gonzini LC 《Journal of environmental quality》2003,32(4):1436-1444
Continued inputs of fertilizer and manure in excess of crop requirements have led to a build-up of soil phosphorus (P) levels and increased P runoff from agricultural soils. The objectives of this study were to determine the effects of two tillage practices (no-till and chisel plow) and a range of soil P levels on the concentration and loads of dissolved reactive phosphorus (DRP), algal-available phosphorus (AAP), and total phosphorus (TP) losses in runoff, and to evaluate the P loss immediately following tillage in the fall, and after six months, in the spring. Rain simulations were conducted on a Typic Argiudoll under a corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] rotation. Elapsed time after tillage (fall vs. spring) was not related to any form of P in runoff. No-till runoff averaged 0.40 mg L(-1) and 0.05 kg ha(-1) DRP and chisel-plow plots averaged 0.24 mg L(-1) and 0.02 kg ha(-1) DRP concentration and loads, respectively. The relationship between DRP and Bray P1 extraction values was approximated by a logistic function (S-shaped curve) for no-till plots and by a linear function for tilled plots. No significant differences were observed between tillage systems for TP and AAP in runoff. Bray P1 soil extraction values and sediment concentration in runoff were significantly related to the concentrations and amounts of AAP and TP in runoff. These results suggest that soil Bray P1 extraction values and runoff sediment concentration are two easily measured variables for adequate prediction of P runoff from agricultural fields. 相似文献