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21.
Transformation toward a sustainable future requires an earth stewardship approach to shift society from its current goal of increasing material wealth to a vision of sustaining built, natural, human, and social capital—equitably distributed across society, within and among nations. Widespread concern about earth’s current trajectory and support for actions that would foster more sustainable pathways suggests potential social tipping points in public demand for an earth stewardship vision. Here, we draw on empirical studies and theory to show that movement toward a stewardship vision can be facilitated by changes in either policy incentives or social norms. Our novel contribution is to point out that both norms and incentives must change and can do so interactively. This can be facilitated through leverage points and complementarities across policy areas, based on values, system design, and agency. Potential catalysts include novel democratic institutions and engagement of non-governmental actors, such as businesses, civic leaders, and social movements as agents for redistribution of power. Because no single intervention will transform the world, a key challenge is to align actions to be synergistic, persistent, and scalable.  相似文献   
22.
This study advances the limited research on work alignment and work engagement by investigating how perceived alignment of job tasks and organizational strategic priorities (strategic alignment) influences work engagement. Measures of job control and work social support were also included to enable comparisons between strategic alignment and other well‐established job resources. A total of 1011 employees of an Australian state police service responded to three electronic, self‐report surveys. A reciprocal model was assessed over three waves of data, with varying time lags: 18 (Time 1 to Time 2), 12 (Time 2 to Time 3), and 30 months (Time 1 to Time 3). Longitudinal, reciprocal relationships were observed for work engagement and job control, strategic alignment, and colleague support. Work engagement also predicted supervisor support over time (reverse effect). This study demonstrated that, in addition to job resources, perceived alignment of job tasks and organizational priorities plays an important role in maintaining high levels of work engagement over time. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
23.
Stirzaker R  Biggs H  Roux D  Cilliers P 《Ambio》2010,39(8):600-607
Decision makers responsible for natural resource management often complain that science delivers fragmented information that is not useful at the scale of implementation. We offer a way of negotiating complex problems by putting forward a requisite simplicity. A requisite simplicity attempts to discard some detail, while retaining conceptual clarity and scientific rigor, and helps us move to a new position where we can benefit from new knowledge. We illustrate the above using three case studies: elephant densities and vegetation change in a national park, the use of rules of thumb to support decision making in agriculture, and the management of salt in irrigation. We identify potential requisite simplicities that can allow us to generate new understanding, lead to action and provide opportunities for structured learning.  相似文献   
24.
This research demonstrated that sterol-inhibiting fungicides alter the population structure of some pest and beneficial arthropods in apple orchards. Orchard populations of European red mite, Panonychus ulmi (Koch) (Acarina: Tetranychidae); the predacious mite, Typhlodromus caudiglans Schuster (Acarina: Phytoseiidae); the spotted tentiform leafminer, Phyllonorycter blancardella Fabr. (Lepidoptera: Gracillariidae); the leafminer parasite Pholetesor ornigis Weed (Hymenoptera: Braconidae); the green apple aphid, Aphis pomi DeGeer (Homoptera: Aphididae); white apple leafhopper, Typhlocyba pomaria McAtee (Homoptera: Cicadellidae); Campylomma verbasci Meyer (Hemiptera: Miridae); chalcids, primarily Sympiesis sericeicornis Nees (Hymenoptera: Chalcididae), were monitored for two growing seasons in a McIntosh apple orchard that had received applications, at 2-week intervals, of two sterol-inhibiting fungicides, bitertanol and flusilazole. High rates of flusilazole were associated with increased numbers of European red mite and decreased numbers of predacious mite species, particularly T. caudiglans. Trees receiving a high rate of bitertanol had fewer European red mites and predacious mite species. Fungicides did not influence spotted tentiform leafminer oviposition or the number of leafminer larvae in May and June 1985. However, in September 1985 there were fewer leafminer pupae in plots treated with the two lower rates of flusilazole and more larvae in plots treated with the high rate of bitertanol, relative to trees sprayed with captan. In 1986, there were more leafminer eggs in plots treated with the low rate of bitertanol compared with captan and non-sprayed trees. However, by 24 June, all treatments showed similar levels of leafminer larvae and pupae. Populations of P. ornigis were generally higher in trees treated with flusilazole in both years. Numbers of aphids and mullein bug were higher in trees treated with flusilazole relative to non-sprayed and captan-treated trees. Chalcid populations were higher in bitertanol-treated trees. Fungicides had no apparent effect on populations of white apple leafhopper.  相似文献   
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The loss of phosphorous (P) from the landscape is commonly viewed as deleterious for surface water quality. However, the quantities lost and the impact this can have on surface waters depends on numerous mechanisms that occur whilst en route. The aim of this review is to give an outline of these mechanisms and thus how sources of P in the agricultural landscape are connected to the impairment of surface water quality. Processes are dealt with by examining the potential for P loss from the landscape and its availability to aquatic plants during flow overland and subsurface flow and once in streamflow or a lake or reservoir. By examining the connectivity between P loss and the impact on surface water quality, potential mitigation and management of P losses are discussed for various aquatic systems.  相似文献   
27.
The concept of an organism's niche is central to ecological theory, but an operational definition is needed that allows both its experimental delineation and interpretation of field distributions of the species. Here we use population growth rate (hereafter, pgr) to define the niche as the set of points in niche space where pgr > 0. If there are just two axes to the niche space, their relationship to pgr can be pictured as a contour map in which pgr varies along the axes in the same way that the height of land above sea level varies with latitude and longitude. In laboratory experiments we measured the pgr of Daphnia magna over a grid of values of pH and Ca2+, and so defined its "laboratory niche" in pH-Ca2+ space. The position of the laboratory niche boundary suggests that population persistence is only possible above 0.5 mg Ca2+/L and between pH 5.75 and pH 9, though more Ca2+ is needed at lower pH values. To see how well the measured niche predicts the field distribution of D. magna, we examined relevant field data from 422 sites in England and Wales. Of the 58 colonized water bodies, 56 lay within the laboratory niche. Very few of the sites near the niche boundary were colonized, probably because pgr there is so low that populations are vulnerable to extinction by other factors. Our study shows how the niche can be quantified and used to predict field distributions successfully.  相似文献   
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