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Jan Christian Habel Andreas Segerer Werner Ulrich Olena Torchyk Wolfgang W. Weisser Thomas Schmitt 《Conservation biology》2016,30(4):754-762
Environmental changes strongly impact the distribution of species and subsequently the composition of species assemblages. Although most community ecology studies represent temporal snap shots, long‐term observations are rather rare. However, only such time series allow the identification of species composition shifts over several decades or even centuries. We analyzed changes in the species composition of a southeastern German butterfly and burnet moth community over nearly 2 centuries (1840–2013). We classified all species observed over this period according to their ecological tolerance, thereby assessing their degree of habitat specialisation. This classification was based on traits of the butterfly and burnet moth species and on their larval host plants. We collected data on temperature and precipitation for our study area over the same period. The number of species declined substantially from 1840 (117 species) to 2013 (71 species). The proportion of habitat specialists decreased, and most of these are currently endangered. In contrast, the proportion of habitat generalists increased. Species with restricted dispersal behavior and species in need of areas poor in soil nutrients had severe losses. Furthermore, our data indicated a decrease in species composition similarity between different decades over time. These data on species composition changes and the general trends of modifications may reflect effects from climate change and atmospheric nitrogen loads, as indicated by the ecological characteristics of host plant species and local changes in habitat configuration with increasing fragmentation. Our observation of major declines over time of currently threatened and protected species shows the importance of efficient conservation strategies. 相似文献
314.
Guided group discussion (
[Lewin et?al., 1952]
,
[Werner, 2003]
and
[Werner and Adams, 2001]
) was used to persuade groups to replace their toxic home and garden chemicals with nontoxic alternatives. We hypothesized that discussion would allow participants to hear others endorse the new information, and this normative information would facilitate persuasion. Approximately two months after the group discussion, we obtained questionnaires from the organizer of the meeting and a member of the group who had missed the meeting because of another obligation (i.e., not because of disinterest in the topic). Most organizers were female and analyses were limited to females. This quasi-experimental matched control group design indicated that those who attended the meeting were more favorable towards using nontoxics and more interested in sharing leftover toxic products with friends (instead of discarding them). Path and mediation analyses showed that the organizer’s evaluation of the meeting predicted her final attitude, and perceptions that the group endorsed the material (perceived group norm) partially mediated this relationship. A second mediation analysis showed that evaluation of the meeting predicted intention to share leftover toxics and this relationship was fully mediated by the organizer’s impression that the group would also share leftovers. The results support the idea that persuasion is based both on individual evaluation and normative influence, especially when people are not confident others will accept the behavior, such as sharing leftover toxic products. 相似文献
315.
MOTIVATIONS AND BEHAVIORS THAT SUPPORT RECYCLING 总被引:2,自引:0,他引:2
This paper proposes that recycling researchers should pay attention to both attitudes towards recycling and the processes involved in recycling (recyclers' phenomenal experiences and organizing strategies). As predicted by Sansone and colleagues' model of how people induce themselves to engage in necessary but boring tasks, people who had reasons to persist at recycling (that is, who held strong prorecycling attitudes or had a social orientation towards recycling) were more likely to redefine recycling so as to emphasize its pleasures or the sense of satisfaction they gained from contributing to the environment. These people were also more likely to have developed a way of organizing recycling in their homes, to report few interferences with recycling, and—most important—to recycle on both short- and long-term bases. In accord with the model, people who became better recyclers by Time 2 had had stronger prorecycling attitudes at Time 1 than people who remained poor recyclers. Our results are consistent with the view that people who make a valued but uninteresting task more phenomenally interesting and more manageable are more likely to continue at the task. Sansone and colleagues' model provides a useful way to look at recycling and also suggests a new way that attitudes may be linked to behavior—via cognitive transformation of behavior. 相似文献
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318.
Trachurus capensis is an important fisheries resource in the degraded Namibian upwelling ecosystem. Food supply and shoaling of hypoxic zones are hypothesised to influence the species’ recruitment success. This paper is the first to quantify energy requirements and hypoxia tolerance of larval and juvenile stages of a Trachurus species. We measured normoxic respiration rates of T. capensis with a size range from 0.001 to 20.8 g wet mass (WM) collected off Cape Town (33.9°S, 18.5°E, 12/2009) and in the northern Benguela (17–24°S, 11–15°E, 02/2011). Routine metabolic rate (RMR) and standard routine rate (SRR) (mg O2 h?1) followed the allometric functions RMR = 0.418 WM0.774 and SRR = 0.275 WM0.855, respectively. Larvae and juveniles had comparatively high metabolic rates, and the energy demand of juveniles at the upper end of the size range appeared too high to be fuelled by a copepod diet alone. T. capensis’ early life stages showed a high tolerance to hypoxic conditions. RMR in larvae did not change until 30 % O2sat at 18 °C. In juveniles, critical oxygen saturation levels were low (PC for SRR = 11.2 ± 1.7 % O2sat and PC for RMR = 13.2 ± 1.6 % O2sat at 20 °C) and oxy-regulation effective (regulation index = 0.78 ± 0.09). A high hypoxia tolerance may facilitate the retention of larvae in near-shore waters providing favourable feeding conditions and allowing juveniles to exploit food resources in the oxygen minimum zone. These mechanisms seem to well adapt T. capensis to a habitat affected by spreading hypoxic zones and probably enhance its recruitment success. 相似文献
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Biodegradable (compostable) packaging materials made from biopolymers (BP) are introduced into the market to reduce the amounts of conventional packaging materials and at the same time be recovered by the municipal organic waste collection system. The processing of this organic waste mixed with biopolymers has been tested in a commercial treatment facility. The safe use of the compost produced from these materials was demonstrated in a full-scale agricultural application test. 相似文献