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221.
Sarah Caronni Maria Anna Delaria Augusto Navone Pieraugusto Panzalis Nicola Sechi Giulia Ceccherelli 《Marine Biology》2014,161(8):1787-1798
Chrysophaeum taylorii (Pelagophyceae) is an allochthonous benthic microalga recently recorded in the Mediterranean Sea. During summer, the occurrence of C. taylorii is usually visible to the naked eye due to the large amount of mucilage this species produces. Information on the spatio-temporal variability of this species and on the predictability of massive mucilage events is still scarce and requires to define ad hoc managing strategies of major bloom events. The aim of this work was to identify the relevant scales of variation in the abundance of C. taylorii abundance and to estimate the relative recurrence of its blooms, testing the hypothesis that mucilage was dependent on the cell density. The first approach was the identification of the most appropriate sampling procedure to estimate benthic cell abundance of C. taylorii. The second one was the estimation of the magnitude of variation in C. taylorii cell abundance attributable to each of several spatial (areas, sites, zones and replicates) and temporal scales (fortnights and years) in the Marine Protected Area of Tavolara Punta Coda Cavallo (Western Mediterranean Sea). The results indicate fortnight and year as the most relevant scales of variability in the cell abundance of C. taylorii and highlight the unimportance of small spatial scales (zone and replicates) to the species variability. The collected data also evidence the absence of a direct relationship between the cell density of C. taylorii and the production of mucilage. In conclusion, these results indicate that patterns in the cell abundance of C. taylorii vary notably depending on the considered scale and that future investigations on processes affecting its performance will need to consider the relevant scales of variation evidenced. 相似文献
222.
Some policy problems pit one group?s interests against another?s. One group may determine provision of a project (such as a dam) that benefits group members but hurts others. We introduce a model of such projects. In-group members may contribute to a common fund that benefits them as a public good. Benefits from the project may vary within the group. Provision has negative downstream externalities: contributions hurt agents outside the in-group (“Outsiders”), rendering them anti-social. Many models of social preferences predict that such externalities should reduce provision, although conditional cooperation or a preference for in-group members may counteract this. We test this model with a lab experiment using Outsiders with whom the in-group members have more and less contact. With homogeneous in-group benefits, the presence of negative downstream externalities reduces contributions by half when they have closer contact with Outsiders but not at all when they have had no contact. We introduce a rotating high-return position that allows subjects to trade favors. In this setting, contributions of non-privileged members diminish slightly when faced with the negative externality given closer contact with Outsiders, and not at all with less contact. Reciprocal giving occurs whether or not Outsiders are present. 相似文献
223.
Tomas Chaigneau Sarah Coulthard Katrina Brown Tim M. Daw Björn Schulte-Herbrüggen 《Conservation biology》2019,33(3):655-664
Conservation managers frequently face the challenge of protecting and sustaining biodiversity without producing detrimental outcomes for (often poor) human populations that depend on ecosystem services for their well-being. However, mutually beneficial solutions are often elusive and can mask trade-offs and negative outcomes for people. To deal with such trade-offs, ecological and social thresholds need to be identified to determine the acceptable solution space for conservation. Although human well-being as a concept has recently gained prominence, conservationists still lack tools to evaluate how their actions affect it in a given context. We applied the theory of human needs to conservation by building on an extensive historical application of need approaches in international development. In an innovative participatory method that included focus groups and household surveys, we evaluated how human needs are met based on locally relevant thresholds. We then established connections between human needs and ecosystem services through key-informant focus groups. We applied our method in coastal East Africa to identify households that would not be able to meet their basic needs and to uncover the role of ecosystem services in meeting these. This enabled us to identify how benefits derived from the environment were contributing to meeting basic needs and to consider potential repercussions that could arise through changes to ecosystem service provision. We suggest our approach can help conservationists and planners balance poverty alleviation and biodiversity protection and ensure conservation measures do not, at the very least, cause serious harm to individuals. We further argue it can be used as a basis for monitoring the impacts of conservation on multidimensional poverty. 相似文献
224.
Sorrel Jones Sarah Papworth Aidan M. Keane Juliet Vickery Freya A. V. St John 《Conservation biology》2021,35(2):722-732
Conservationists need to measure human behavior to guide decisions and evaluate their impact. However, activities can be misreported and reporting accuracy may change following conservation interventions, making it hard to verify any apparent changes. Techniques for asking sensitive questions are increasingly integrated into survey designs to improve data quality, but some can be costly or hard for nonexperts to implement. We demonstrate a straightforward, low-cost approach, the bean method in which respondents give anonymous answers by adding a colored bean to a jar to denote a yes or no response. We applied the bean method to measure wild-meat hunting and trading over 2 years at a conservation-project (hunting reduction) site in Gola Forest, Liberia. We extended the technique to accommodate questions about hunting and meat-selling frequency. We compared responses given using the bean method and direct questioning for groups that did and did not participate in conservation interventions. Results from the bean method corresponded to those from direct questioning, and there was no indication of change in question sensitivity following conservation interventions. Estimates from both methods indicated that wild-meat trading decreased in project and nonproject households (from 36% to 20%) and that hunting decreased in 1 project group (38–28%). Where inconsistent answers were given (2–6% of respondents), differences were in both directions and were most likely attributable to measurement error. The bean method was quick and straightforward to administer in a low-literacy setting. We showed how it can be modified for answers of more than 2 categories and consider it a valuable tool that could be adapted for a wide range of conservation settings. 相似文献
225.
226.
Michael P. Harris Francis Daunt Mark Newell Richard A. Phillips Sarah Wanless 《Marine Biology》2010,157(4):827-836
Most seabirds die outside the breeding season, but understanding the key factors involved is hampered by limited knowledge
of nonbreeding distributions. We used miniature geolocating loggers to examine the movements between breeding seasons of Atlantic
puffins Fratercula arctica from a major North Sea colony where numbers have declined in recent years, apparently due to increased overwinter mortality.
The most intensively used region was the northwestern North Sea but most puffins also made excursions into the east Atlantic
in the early winter. Ringing recoveries previously indicated that adults from British east coast colonies remained within
the North Sea and hence were spatially segregated from those breeding on the west throughout the year. Updated analyses of
ringing recoveries support results from geolocators suggesting that usage of Atlantic waters is a recent phenomenon. We propose
that the increased adult mortality is related to changes in distribution during the nonbreeding period and reflects worsening
conditions in the North Sea. 相似文献
227.
Teodora B. Toshova Dimitar I. Velchev Mitko A. Subchev Miklós Tóth József Vuts John A. Pickett Sarah Y. Dewhirst 《Chemoecology》2010,20(3):199-206
The grey corn weevil, Tanymecus (Episomecus) dilaticollis, is an economically important polyphagous pest in Eastern and Central Europe. The present research is the first published
electrophysiological study of olfactory sensitivity of adult T. dilaticollis to plant volatiles. The electrophysiological responses of male and female antennae were recorded to 20 synthetic volatile
organic compounds (VOCs), previously identified to be released from the preferred host plants, maize and sunflower. Antennae
of both sexes responded to a wide range of volatiles from different chemical classes: fatty acid derivatives, aromatic compounds
and terpenoids. Two green leaf volatiles, (E)-2-hexen-1-ol and (Z)-3-hexen-1-ol, and one terpenoid, (±)-linalool, elicited the strongest electrophysiological responses by male and female
antennae. Relatively high electrophysiological activity by T. dilaticollis antennae was also recorded to benzaldehyde, eugenol and caryophyllene. In the field, (E)-2-hexen-1-ol and (Z)-3-hexen-1-ol, when presented individually, caught significantly more male and female T. dilaticollis than unbaited controls. These compounds could be developed into an attractive trap for the detection and monitoring of T. dilaticollis. 相似文献
228.
Sarah Ewing 《Journal of the American Water Resources Association》1999,35(3):663-673
ABSTRACT: Australia's ‘Landcare’ program is a community-based participatory program established by government to tackle the problem of land degradation. Landcare involves thousands of Australians working together in locally based groups, tackling problems of common concern. Government and community are now looking to ‘scale up’ the Landcare idea to a regional level. State and territory governments have moved to create regional (often watershed-based) frameworks for land management planning and resource conservation, in accordance with the concept of integrated watershed management. Growing out of the success of community involvement in Landcare, many of these approaches involve the community. However scaling up of the Landcare idea introduces problems of both time and space. There have been a number of problems experienced in the implementation of Landcare and integrated watershed management. These problems include the equitable delineation of membership on decision-making bodies; the raising of sufficient funds for program implementation; and the coordination of a diversity of governmental layers, planning processes and management programs. This paper reviews how the State of Victoria has responded to these challenges and suggests what challenges remain. 相似文献
229.
230.
Baglieri Andrea Sidella Sarah Barone Valeria Fragalà Ferdinando Silkina Alla Nègre Michèle Gennari Mara 《Environmental science and pollution research international》2016,23(18):18165-18174
Environmental Science and Pollution Research - This work evaluates the possibility of cultivating Scenedesmus quadricauda and Chlorella vulgaris microalgae in wastewater from the hydroponic... 相似文献