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631.
Jack H. Hatfield Jos Barlow Carlos A. Joly Alexander C. Lees Celso Henrique de Freitas Parruco Joseph A. Tobias C. David L. Orme Cristina Banks-Leite 《Conservation biology》2020,34(2):395-404
Habitat loss, fragmentation, and degradation have pervasive detrimental effects on tropical forest biodiversity, but the role of the surrounding land use (i.e., matrix) in determining the severity of these impacts remains poorly understood. We surveyed bird species across an interior-edge-matrix gradient to assess the effects of matrix type on biodiversity at 49 different sites with varying levels of landscape fragmentation in the Brazilian Atlantic Forest—a highly threatened biodiversity hotspot. Both area and edge effects were more pronounced in forest patches bordering pasture matrix, whereas patches bordering Eucalyptus plantation maintained compositionally similar bird communities between the edge and the interior and exhibited reduced effects of patch size. These results suggest the type of matrix in which forest fragments are situated can explain a substantial amount of the widely reported variability in biodiversity responses to forest loss and fragmentation. 相似文献
632.
633.
L. Ignacio Vilchis Joseph R. Evenson Scott F. Pearson Karen L. Barry Peter Davidson Martin G. Raphael Joseph K. Gaydos 《Conservation biology》2015,29(1):154-163
Identifying drivers of ecosystem change in large marine ecosystems is central for their effective management and conservation. This is a sizable challenge, particularly in ecosystems transcending international borders, where monitoring and conservation of long‐range migratory species and their habitats are logistically and financially problematic. Here, using tools borrowed from epidemiology, we elucidated common drivers underlying species declines within a marine ecosystem, much in the way epidemiological analyses evaluate risk factors for negative health outcomes to better inform decisions. Thus, we identified ecological traits and dietary specializations associated with species declines in a community of marine predators that could be reflective of ecosystem change. To do so, we integrated count data from winter surveys collected in long‐term marine bird monitoring programs conducted throughout the Salish Sea—a transboundary large marine ecosystem in North America's Pacific Northwest. We found that decadal declines in winter counts were most prevalent among pursuit divers such as alcids (Alcidae) and grebes (Podicipedidae) that have specialized diets based on forage fish, and that wide‐ranging species without local breeding colonies were more prone to these declines. Although a combination of factors is most likely driving declines of diving forage fish specialists, we propose that changes in the availability of low‐trophic prey may be forcing wintering range shifts of diving birds in the Salish Sea. Such a synthesis of long‐term trends in a marine predator community not only provides unique insights into the types of species that are at risk of extirpation and why, but may also inform proactive conservation measures to counteract threats—information that is paramount for species‐specific and ecosystem‐wide conservation. Evaluación de las Correlaciones Ecológicas de las Declinaciones de Aves Marinas para Informar a la Conservación Marina 相似文献
634.
Nicholas Joseph Tavares da Cruz Álvaro Guillermo Rojas Lezana Paulo da Cruz Freire dos Santos Ibsen Mateus Bittencourt Santana Pinto Claudio Zancan Gustavo Henrique Silva de Souza 《Environmental science and pollution research international》2017,24(31):24121-24134
Cemeteries and crematoria are the main funeral ways used in the world nowadays. It is a little-studied segment in the present days, mainly as for the possible environmental impacts in the environment, such as those derived from dental amalgam, prostheses, and dioxins, among other. This article aimed to identify the environmental impacts caused by cemeteries and crematoria and to point out new trends in funeral processes such as freeze-drying and alkaline hydrolysis. The study is justified due to the large part of the Brazilian population that do not know the environmental impacts caused by cemeteries and crematoria, as well as to bring information about the new processes. For that, a research was carried out with 400 people. The main results show that among all the funeral processes, the new freeze-drying process was opted by 33% of the sample. We also identified that the main reasons for choosing the funeral process were less environmental impact (28%), no after-death expenses (grave payment) (16.1%), and the possibility of putting away or throwing away the remains wherever you want (14.9%). Finally, new funeral processes were well accepted by the Brazilian population—those who were interviewed—due to their benefits. 相似文献
635.
Joseph B. Pfaller Joanna Alfaro-Shigueto George H. Balazs Takashi Ishihara Kerry Kopitsky Jeffrey C. Mangel S. Hoyt Peckham Alan B. Bolten Karen A. Bjorndal 《Marine Biology》2014,161(9):2167-2178
Studies that incorporate information from habitat-specific ecological interactions (e.g., epibiotic associations) can reveal valuable insights into the cryptic habitat-use patterns and behavior of marine vertebrates. Sea turtles, like other large, highly mobile marine vertebrates, are inherently difficult to study, and such information can inform the implementation of conservation measures. The presence of epipelagic epibionts, such as the flotsam crab Planes major, on sea turtles strongly suggests that neritic turtles have recently occupied epipelagic habitats (upper 200 m in areas with >200 m depth) and that epipelagic turtles spend time at or near the surface. We quantified the effects of turtle species, turtle size, and habitat (neritic or epipelagic) on the frequency of epibiosis (F 0) by P. major on sea turtles in the Pacific Ocean. In neritic habitats, we found that loggerhead (F 0 = 27.6 %) and olive ridley turtles (F 0 = 26.2 %) host crabs frequently across a wide range of body sizes, and green turtles almost never host crabs (F 0 = 0.7 %). These results suggest that loggerheads and olive ridleys display variable/flexible epipelagic-neritic transitions, while green turtles tend to transition unidirectionally at small body sizes. In epipelagic habitats, we found that loggerheads host crabs (F 0 = 92.9 %) more frequently than olive ridleys (F 0 = 50 %) and green turtles (F 0 = 38.5 %). These results suggest that epipelagic loggerheads tend to spend more time at or near the surface than epipelagic olive ridleys and green turtles. Results of this study reveal new insights into habitat-use patterns and behavior of sea turtles and display how epibiont data can supplement data from more advanced technologies to gain a better understanding of the ecology of marine vertebrates during cryptic life stages. 相似文献
636.
Dissolved organic carbon concentrations and fluxes in forest catchments and streams: DOC-3 model 总被引:3,自引:0,他引:3
Marie-France JutrasMina Nasr Mark CastonguayChristopher Pit Joseph H. PomeroyTodd P. Smith Cheng-fu ZhangCharles D. Ritchie Fan-Rui MengThomas A. Clair Paul A. Arp 《Ecological modelling》2011,222(14):2291-2313
Dissolved organic carbon (DOC) concentrations in south-western Nova Scotia streams, sampled at weekly to biweekly intervals, varied across streams from about 3 to 40 mg L−1, being highest mid-summer to fall, and lowest during winter to spring. A 3-parameter model (DOC-3) was proposed to project daily stream DOC concentrations and fluxes from modelled estimates for daily soil temperature and moisture, year-round, and in relation to basin size and wetness. The parameters of this model refer to (i) a basin-specific DOC release parameter “kDOC”, related to the wet- and open-water area percentages per basin, (ii) the lag time “τ” between DOC production and subsequent stream DOC emergence, related to the catchment area above the stream sampling location; and (iii) the activation energy “Ea”, to deal with the temperature effect on DOC production. This model was calibrated with the 1988-2006 DOC concentration data from three streams (Pine Marten, Moosepit Brook, and the Mersey River sampled at or near Kejimkujik National Park, or KNP), and was used to interpret the biweekly 1999-2003 DOC concentrations data (stream, ground and lake water, soil lysimeters) of the Pockwock-Bowater Watershed Project near Halifax, Nova Scotia. The data and the model revealed that the DOC concentrations within the streams were not correlated to the DOC concentrations within the soil- and groundwater, but were predictable based on (i) the hydrologically inferred weather-induced changes in soil moisture and temperature next to each stream, and (ii) the topographically inferred basin area and wet- and open-water area percentages associated with each stream (R2 = 0.53; RMSE = 3.5 mg L−1). Model-predicted fluxes accounted 74% of the hydrometrically determined DOC exports at KNP. 相似文献
637.
Jean T. Ellis Joseph P. Spruce Roberta A. Swann James C. Smoot Kent W. Hilbert 《Journal of Coastal Conservation》2011,15(1):139-149
The purpose of this research is to quantify and assess geospatial land-use and land-cover (LULC) changes in the coastal counties
of Mobile and Baldwin, Alabama using nine Landsat images from 1974–2008. A study-specific classification scheme was devised
comprising upland herbaceous, upland forest, non-woody and woody wetlands, open water, and urban categories. Upland forest
was the most dominant terrestrial cover type. Wetlands averaged 17% and urban averaged 7%. A majority of the urban expansion
occurred between 1974 and 1979 (26%). Thirty-four percent of the 2008 urban areas were upland forest in 1974. Watershed-scale
analysis of Three Mile Creek and D’Olive Bay highlights the temporal and spatial differences of urbanization for watersheds
found within the same region. This study is a Gulf of Mexico Alliance (GOMA) Application Pilot project that uses NASA data
products to benefit coastal environmental managers and community members. Results have led to increased effectiveness of coastal
conservation decision-making, increased understanding of post-hurricane LULC change, continued research on habitat change
impacts, and contributed to timely conservation planning efforts. This study has benefited the development of watershed management
plans by the Mobile Bay National Estuary Program, which is especially important given projected climate change. 相似文献
638.
Negative attitudes of resident communities towards conservation are associated with resource decline in developing countries. In Botswana, Community-Based Natural Resource Management (CBNRM) was adopted to address this challenge. CBNRM links rural development and conservation. However, the impact of CBNRM on changes of resident attitudes towards conservation and tourism is not adequately researched. This paper, therefore, assesses the impacts of CBNRM on resident attitudes towards tourism development and conservation in the Okavango Delta, Botswana. The study purposively sampled villages of Khwai, Mababe and Sankoyo. Household data using variables like: economic benefits from CBNRM; level of satisfaction with CBNRM; co-management of natural resources between resident communities and government agencies; and collective action was collected. This data was supplemented by secondary and ethnographic data. Using qualitative and quantitative analysis, results indicate changes in resident attitudes from being negative to positive towards tourism and conservation. These changes are triggered by economic benefits residents derived from CBNRM, co-management in resource management; and, collective action of communities in CBNRM development. Positive attitudes towards conservation and tourism are the first building blocks towards achieving conservation in nature-based tourism destinations. As a result, decision-makers should give priority to CBNRM and use it as a tool to achieve conservation and improved livelihoods in nature-based tourism destinations of developing countries. 相似文献
639.
Over the past several decades, we have argued that cultural evolution can facilitate the evolution of large-scale cooperation
because it often leads to more rapid adaptation than genetic evolution, and, when multiple stable equilibria exist, rapid
adaptation leads to variation among groups. Recently, Lehmann, Feldman, and colleagues have published several papers questioning
this argument. They analyze models showing that cultural evolution can actually reduce the range of conditions under which
cooperation can evolve and interpret these models as indicating that we were wrong to conclude that culture facilitated the
evolution of human cooperation. In the main, their models assume that rates of cultural adaption are not strong enough compared
to migration to maintain persistent variation among groups when payoffs create multiple stable equilibria. We show that Lehmann
et al. reach different conclusions because they have made different assumptions. We argue that the assumptions that underlie
our models are more consistent with the empirical data on large-scale cultural variation in humans than those of Lehmann et
al., and thus, our models provide a more plausible account of the cultural evolution of human cooperation in large groups. 相似文献
640.
Joseph P. Essien Stephen I. Eduok Abass Abiola Olajire 《Environmental monitoring and assessment》2011,176(1-4):99-107
The distribution of polycyclic aromatic hydrocarbons (PAHs) in epipelic and benthic sediments from Iko River estuary mangrove ecosystem has been investigated. Total PAHs ranged from 6.10 to 35.27 mg/kg dry weight. Quantitative difference between the total PAHs in epipelic and benthic sediments showed that the benthic sediment known for higher capability to serve as sink for chemical pollutants accumulated less PAHs. This implies that PAHs in the epipelic sediment may plausibly be from industrial sources via runoff and/or of biogenic origin. A strong pyrolytic source fingerprint has been detected with slight influence of petrogenic sources. Total organic carbon normalized PAHs (sum of 16 PAHs, 59.7 to 372.4 mg/kg OC) were under (except for ES3 and BS3) the threshold effects concentrations (TEC, 290 mg/kg OC). Total PAHs in Iko River estuary sediments were in the range between ERL and ERM. 相似文献