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101.
Rupert Seidl Filip Aggestam Werner Rammer Kristina Blennow Bernhard Wolfslehner 《Ambio》2016,45(4):430-441
Climate vulnerability of managed forest ecosystems is not only determined by ecological processes but also influenced by the adaptive capacity of forest managers. To better understand adaptive behaviour, we conducted a questionnaire study among current and future forest managers (i.e. active managers and forestry students) in Austria. We found widespread belief in climate change (94.7 % of respondents), and no significant difference between current and future managers. Based on intended responses to climate-induced ecosystem changes, we distinguished four groups: highly sensitive managers (27.7 %), those mainly sensitive to changes in growth and regeneration processes (46.7 %), managers primarily sensitive to regeneration changes (11.2 %), and insensitive managers (14.4 %). Experiences and beliefs with regard to disturbance-related tree mortality were found to particularly influence a manager’s sensitivity to climate change. Our findings underline the importance of the social dimension of climate change adaptation, and suggest potentially strong adaptive feedbacks between ecosystems and their managers.
Electronic supplementary material
The online version of this article (doi:10.1007/s13280-015-0737-6) contains supplementary material, which is available to authorized users. 相似文献102.
Cumulative Industrial Activity Alters Lotic Fish Assemblages in Two Boreal Forest Watersheds of Alberta,Canada 总被引:1,自引:0,他引:1
We evaluated the cumulative effects of land use disturbance resulting from forest harvesting, and exploration and extraction
of oil and gas resources on the occurrence and structure of stream fish assemblages in the Kakwa and Simonette watersheds
in Alberta, Canada. Logistic regression models showed that the occurrence of numerically dominant species in both watersheds
was related to two metrics defining industrial activity (i.e., percent disturbance and road density), in addition to stream
wetted width, elevation, reach slope, and percent fines. Occurrences of bull trout, slimy sculpin, and white sucker were negatively
related to percent disturbance and that of Arctic grayling, and mountain whitefish were positively related to percent disturbance
and road density. Assessments of individual sites showed that 76% of the 74 and 46 test sites in the Kakwa and Simonette watersheds
were possibly impaired or impaired. Impaired sites in the Kakwa Watershed supported lower densities of bull trout, mountain
whitefish, and rainbow trout, but higher densities of Arctic grayling compared to appropriate reference sites. Impaired sites
in the Simonette Watershed supported lower densities of bull trout, but higher densities of lake chub compared to reference
sites. Our data suggest that current levels of land use disturbance alters the occurrence and structure of stream fish assemblages. 相似文献
103.
The increasing alienation of people from nature is profoundly concerning because people's interactions with nature affect well-being, affinity for nature, and support of biodiversity conservation. Efforts to restore or enhance people's interactions with nature are, therefore, important to ensure sustainable human and wildlife communities, but little is known about how this can be achieved. A key factor that shapes the way people interact with nature is their affinity for nature (often measured as nature relatedness [NR]). We explored how using cues to experience nature as a means to induce NR situationally can influence the quality of people's nature interactions on visits to green spaces and their positive affect after the visit. Cues to experience are cues that guide individuals on how to interact with nature. We surveyed 1023 visitors to a nature reserve to examine the relationships between trait (i.e., stable and long-lasting) and state (i.e., temporary, brief) NR, the quality of nature interactions, and positive affect. We also conducted a controlled experiment in which 303 participants spent 30 min outdoors on campus and reported the quality of their nature interactions and positive affect. Participants were randomly assigned to 1 of 9 cues-to-experience experimental groups (e.g., smell flowers, observe wildlife, turn off your phone) that differed in the psychological distance from nature that they prompted. Participants who received cues of close psychological distance from nature (e.g., smell and touch natural elements) interacted 3 to 4 times more with nature and reported 0.2 more positive affect than other participants. Our results demonstrate that providing cues to experience nature, which bring people closer to nature and potentially induce state NR, can enhance the quality of people's nature interactions and their positive affect. These results highlight the role of NR in high-quality nature interactions and suggest the use of cues to experience as a promising avenue for inducing state NR and promoting meaningful interactions with biodiversity, thus, reconciling conservation and well-being objectives. 相似文献
104.
Rupert Seidl Paulo M. Fernandes Teresa F. FonsecaFrançois Gillet Anna Maria JönssonKatarína Mergani?ová Sigrid NethererAlexander Arpaci Jean-Daniel BontempsHarald Bugmann Jose Ramon González-OlabarriaPetra Lasch Céline MeredieuFrancisco Moreira Mart-Jan SchelhaasFrits Mohren 《Ecological modelling》2011,222(4):903-924
105.
Previous ecological models for disturbance from energetic perspectives have focused on destructive pulses by which storages in a system are quickly drained during disturbance events and recovered thereafter. However, considering the wide range of disturbance intensities, frequencies, and durations in nature, disturbance effects on ecosystem energetics would be better understood by diversifying the disturbance effects on specific system configurations or energy pathways. Based on two hypotheses, we built simulation models of the variable disturbance-productivity relationships observed in a freshwater aquatic microcosm study. First, we hypothesized that disturbances will differentially alter the intrinsic rates of energy pathways in a system. Second, we hypothesized that there is a disturbance threshold where response of the intrinsic rates changes abruptly. Simulation results showed variable patterns of gross primary productivity (GPP) during the disturbance and post-disturbance periods under the diverse scenarios of disturbance effects on the intrinsic rates. Simulation results confirmed that the second hypothesis (i.e., disturbance threshold) was essential to achieve a U-shaped or peaked disturbance-productivity relationship. We evaluated the models by comparing them with the results of the microcosm tests, and suggested possible mechanisms of the variable disturbance-productivity relationships by varying parameters related to the disturbance effects on the intrinsic rates and the disturbance thresholds. 相似文献
106.
Zhenyu Yuan Lisa E. Baranik Robert R. Sinclair Michael T. Sliter Kevin L. Rand Michelle P. Salyers 《组织行为杂志》2019,40(4):417-433
Despite its potential for advancing organizational behavior (OB) research, the topic of death awareness has been vastly understudied. Moreover, research on death awareness has predominantly focused on the anxiety‐provoking aspect of death‐related cognitions, thus overlooking the positive aspect of death awareness, death reflection. This gap is exacerbated by the lack of a valid research instrument to measure death reflection. To address this issue, we offer a systematic conceptualization of death reflection, develop the Death Reflection Scale, and assess its psychometric properties across four studies. Further, using a sample of 268 firefighters, we examine whether death reflection buffers the detrimental impact of mortality cues at work on employee well‐being and safety performance. Results provide strong support for the psychometric properties of the Death Reflection Scale. Further, moderation analysis indicates death reflection weakens the negative effect of mortality cues on firefighters' safety performance. Overall, these findings suggest the newly developed Death Reflection Scale will prove useful in future research on death‐related cognitions. 相似文献
107.
108.
Reintroduction programs for conservation purposes suffer from low post-release survival of captive-bred animals, especially so with fish reintroductions. High mortality is most often due to weakened antipredator skills, which could be enhanced through direct experience with predators and social learning. As yet, the relative efficiency of these learning methods has not been tested, and the significance of the factors determining how efficiently antipredator responses are transmitted socially from experienced (demonstrator) to predator naive (observer) individuals is largely unknown. Using hatchery-bred stock of the endangered Saimaa Arctic charr (Salvelinus alpinus), we show for the first time that: (1) contrary to theoretical predictions, acquired predator recognition was only socially transmitted from predator-experienced to predator-naive fish in groups with a smaller proportion of experienced than naive individuals, and that (2) socially acquired avoidance of the predator odors was as strong as in those fish conditioned with a combination of odors and predator exposure. We conclude that using social transmission procedures in training fish for reintroduction programs may provide considerable ecological, economical and ethical advantages.Communicated by J. Krause 相似文献
109.
Summary. Africanized honey bees (AHBs) of Brazil and Mexico have proven to be tolerant to Varroa destructor mites. In contrast, European honey bees (EHBs: Apis mellifera carnica) at the same tropical study site are highly intolerant to these ectoparasites. A lower attractiveness of Varroa-tolerant AHB larvae has been hypothesised to be an important trait in reducing the susceptibitlity of AHBs to these mites.
Thus, selection for EHB brood that is less attractive to mites is thought to be one possibility for limiting mite population
growth and thus increase the tolerance of EHBs to the mite.?In Ribeir?o Preto, Brazil, European A. m. carnica bees and AHBs were tested with respect to their rate of brood infestation and brood attractiveness to Varroa mites. For the comparison of brood infestation rates, we introduced combs with pieces of EHB and AHB brood into honey bee
colonies (18 repetitions). The relative infestation rate of EHB brood was significantly higher compared to AHB brood.?The
preference behaviour of single Varroa mites was tested in a laboratory bioassay where either living host stages were offered or host extracts were presented on
dummies. By these tests we could confirm the preference of Varroa females for certain developmental host stages and for their corresponding extracts. In contrast to the within-colony results,
Varroa mites in the laboratory bioassay showed a slight preference for AHB compared to EHB larvae.?The gas chromatographic analysis
revealed differences in the chemical spectrum of extracts obtained from different larvae. In accord with the results of the
bioassays, we could detect stage-specific odour differences in larval cuticular compounds, including methyl esters and hydrocarbons
that have been described as kairomones. None of these substances, however, revealed significant race-specific differences.
Therefore, the quantity and composition of certain cuticular compounds seem to be responsible only for the recognition of
a suitable host stage by Varroa females. The different infestation rates in the colonies, however, seem to be caused neither by race-specific differences
in attractiveness of bee larvae nor by an extended attractive period of EHB larvae: both AHB and EHB larvae become attractive
approximately 21 h before capping of the brood cell, and thus have the same window of time when they can be parasitised.?Therefore
differential Varroa-infestation rates are not related to larval attraction but probably are determined by other race-specific and colony-related
factors.
Received 11 June 2001; accepted 19 November 2001. 相似文献
110.
Varenka Lorenzi Ryan L. Earley Matthew S. Grober 《Behavioral ecology and sociobiology》2006,59(6):715-722
Sex change in marine teleost fishes is commonly regulated by social factors. In species that exhibit protogynous sex change,
such as the bluebanded goby Lythrypnus dalli, the most dominant female typically initiates sex change when a male is removed from the social group. Females can use visual,
chemical or tactile cues to assess the presence or absence of a male. The primary goal of our study was to determine whether
the olfactory and visual presence of a male versus its behavioural interactions with females were important for mediating
sex change. We exposed females to three different treatments: absence of a male, presence of a male that could physically
interact with her and presence of a male behind a barrier that allowed visual and olfactory interactions but prohibited physical
interactions. Sex change occurred in the absence of a male but not in the presence of a male that could physically interact
with the female. The presence of a male behind the barrier did not prevent sex change but affected the timing of sex change.
Season appeared to affect the latency to initiate male typical courtship, with a delay at the end of the reproductive season
only when the male was present behind the barrier. We discuss the seasonal results in terms of L. dalli life history and the potential benefits and costs of changing sex late in the season in the presence or absence of aggressive
reinforcement by the male. Our results identify direct behavioural interactions as an important proximate mechanism in the
social regulation of sex change in L. dalli. 相似文献