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221.
Ants are abundant, diverse, and ecologically dominant in tropical forests. Subterranean ants in particular are thought to
have a significant environmental impact, although difficulties associated with collecting ants underground and examining their
ecology and behavior have limited research. In this paper, we present the results of a study of subterranean ant diversity
in Amazonian Ecuador that employs a novel probe to facilitate the discovery of species inhabiting the soil horizon. Forty-seven
species of ants in 19 genera, including new and apparently rare species, were collected in probes. Approximately 19% of the
species collected at different depths in the soil were unique to probe samples. Analysis of similarity (ANOSIM) results showed
that the species composition of ants collected with the probe was significantly different from samples collected using other
techniques. Additionally, ANOSIM computations indicated the species assemblage of ants collected 12.5 cm below the surface
was significantly different from those found at 25, 37.5, and 50 cm. Ant diversity and species accumulation rates decreased
with increasing depth. There were no species unique to the lowest depths, suggesting that subterranean ants may not be distributed
deep in the soil in Amazonia due to the high water table. The technique we describe could be used to gain new insights into
the distribution and biology of subterranean ant species and other members of the species-rich soil invertebrate macrofauna. 相似文献
222.
As with many farmland bird species, the house sparrow Passer domesticus is declining in Europe, mainly due to intensification of agriculture reducing nest sites and food supplies. During 2002–2005,
we studied the population size and nest site characteristics of house sparrows breeding within white stork Ciconia ciconia nests in a large area of agricultural landscape within western Poland. To explain sparrow density within stork nests, we
examined characteristics of white stork nests (position, age, productivity) and the farm type around the nest. House sparrow
density was greatest in the longest established (and hence larger) white stork nests located on traditionally managed farms.
Two recent changes appear to have adverse effects on house sparrows. The first is the intensification of farming and the second
is active management of white stork nests on electric poles to reduce nest size and thus avoid both disruption to the electrical
supply and electrocution of white storks. Because the white stork has such a high profile in Poland, there are numerous schemes
to conserve and enhance this species. In conclusion, we clearly show that protecting one species can have valuable, although
unplanned, benefits to another species of conservation interest, the house sparrow. 相似文献
223.
224.
The term critical habitat is used to describe the subset of habitat that is essential to the survival and recovery of species. Some countries legally require that critical habitat of listed threatened and endangered species be identified and protected. However, there is little evidence to suggest that the identification of critical habitat has had much impact on species recovery. We hypothesized that this may be due at least partly to a mismatch between the intent of critical habitat identification, which is to protect sufficient habitat for species persistence and recovery, and its practice. We used content analysis to systematically review critical habitat documents from the United States, Canada, and Australia. In particular, we identified the major trends in type of information used to identify critical habitat and in occupancy of habitat identified as critical. Information about population viability was used to identify critical habitat for only 1% of the species reviewed, and for most species, designated critical habitat did not include unoccupied habitat. Without reference to population viability, it is difficult to determine how much of a species’ occupied and unoccupied habitat will be required for persistence. We therefore conclude that the identification of critical habitat remains inconsistent with the goal of protecting sufficient habitat to support persistence and recovery of the species. Ensuring that critical habitat identification aligns more closely with its intent will improve the accuracy of the designations and may therefore help improve the benefits to species recovery when combined with adequate implementation and enforcement of legal protections. 相似文献
225.
COLIN M. BEIER 《Conservation biology》2008,22(6):1485-1496
Abstract: To understand how a highly contentious policy process influenced a major conservation effort, I examined the origins, compromises, and outcomes of the Alaska National Interest Lands Conservation Act of 1980 (ANILCA) for the Tongass National Forest. Tongass wilderness designation was among the most controversial issues in the ANILCA debate, and it faced strong opposition from influential lawmakers, land managers, and Alaska residents. To investigate the influence of this opposition on Tongass conservation outcomes, I conducted a gap analysis of Tongass reserves and a policy analysis of the ANILCA debate and traced the influence of specific interests through the amendments, negotiations, and resulting compromises needed to enact ANILCA. Overall, I found that Tongass reserves comprise a broadly representative cross‐section of ecosystems and species habitats in southeastern Alaska. Redrawn reserve boundaries, industry subsidies, and special access regulations reflected compromises to minimize the impact of wilderness conservation on mining, timber, and local stakeholder interests, respectively. Fragmentation of the Admiralty Island National Monument—the most ecologically valuable and politically controversial reserve—resulted from compromises with Alaskan Native (indigenous peoples of Alaska) corporations and timber interests. Despite language to accommodate “reasonable access” to wilderness reserves, ongoing access limitations highlight the concerns of Alaska residents that opposed ANILCA several decades ago. More broadly, the Tongass case suggests that early and ambitious conservation action may offset strong political opposition; compromises needed to establish key reserves often exacerbate development impacts in unprotected areas; and efforts to minimize social conflicts are needed to safeguard the long‐term viability of conservation measures. 相似文献
226.
Natura 2000 is the core of the EU's biodiversity conservation policy. 50% of the overall protected area under Natura 2000 is forest. Yet, comparatively little is known about the implementation of the policy in forests. Building on a rich set of social and natural science data, and an inter- and transdisciplinary discussion process involving scientists from different disciplines as well as EU, national and local stakeholders, this paper identifies five important challenges related to the implementation of Natura 2000 in forests: (1) the balancing of biodiversity conservation and timber production, (2) the integration of conservation (science) and local stakeholders’ demands, (3) climate change, (4) lacking and less effective funding, and (5) conflicts related to other sectoral policies. Subsequently, five possible pathways to tackle these challenges are proposed: (1) a learning approach through better communication and transparency, (2) a pathway emphasizing the role of conservation science in developing management strategies and responding to climate change, (3) an approach of better integrating Europe's citizens in the design and implementation of the policy, (4) an approach highlighting the necessity of an effective funding strategy, and (5) the vision to work towards an integrated European land use and conservation policy. In conclusion, we emphasize, on one hand, the distinct character of the five pathways but, on the other hand, underline that probably all of them need to be followed in order to make the implementation of Natura 2000 in Europe's forests a success story. 相似文献
227.
The footprint of human activities within Antarctica is increasing, making it essential to consider whether current conservation/protection of environmental and scientific values is adequate. The Antarctic protected area network has developed largely without any clear strategy, despite scientific attempts to promote protection of representative habitats. Many Antarctic Specially Protected Area (ASPA) Management Plans do not state clearly if conservation or science is the priority objective. This is problematic as science and conservation may have conflicting management requirements, i.e. visitation may benefit science, but harm conservation values. We examined recent estimated mean annual levels of visitation to ASPAs. On average, ASPAs protecting scientific research interests were visited twice as often as ASPAs conserving Antarctic habitat and biological communities. However, ASPAs protecting both science and conserving habitat were visited three times as often as ASPAs conserving habitat alone. Examination of visitation data showed that the proportion of visitors entering ASPAs for science, environmental management and/or education and tourism purposes, did not reflect the primary reason for designation, i.e. for science and/or conservation. One third of APSAs designated since the Environmental Protocol entered into force (1998) did not describe clearly the main reason for designation. Policy makers should consider (i) for all Management Plans stating unambiguously the reason an area has ASPA designation, e.g. either to protect habitat/environmental values or scientific research, in accordance with adopted guidance, (ii) designating new protected areas where visitation is kept to an absolute minimum to ensure the long-term conservation of Antarctic species and habitats without local human impacts (possibly located far from areas of human activity), and (iii) encouraging the use of zoning in ASPAs to help facilitate the current and future requirements of different scientific disciplines. 相似文献
228.
The present paper addresses the conservation planning and management issues of terrestrial ecosystems with particular insight to small islands (with examples of application in the Macaronesian archipelagos of Cape Verde, Canaries, Madeira and Azores). It analyses specific conservation planning and management approaches and proposes concrete characterization and evaluation frameworks able to support decision and management processes ensuring an active and participative involvement of all concerned stakeholders. These methodological perspectives involve not only new paradigmatic approaches to the process of characterization and evaluation of environmental elements and processes as well as their use and disturbance through land use, but also regarding the individual and collective perspectives regarding benefice and supporting management behaviours. Some examples from islands of the Macaronesian archipelagos, in particular Pico in the archipelago of Azores and Santiago in the Cape Verde archipelago, are used to illustrate some possible management approaches, involving the consideration of the entire island as a conservation object and mobilizing their actors (individuals, groups, administrations or other organizations) as conscious, participative stakeholders. These examples involve possible land use and management changes and trade-off processes specific to each island that are listed and explained. 相似文献
229.
Peter C. Smiley Jr. F. Douglas Shields Jr. Scott S. Knight 《Journal of the American Water Resources Association》2009,45(4):867-878
Abstract: Conservation practices are regularly implemented within agricultural watersheds throughout the United States without evaluating their ecological impacts. Impact assessments documenting how habitat and aquatic biota within streams respond to these practices are needed for evaluating the effects of conservation practices. Numerous sampling protocols have been developed for monitoring streams. However, protocols designed for monitoring studies are not appropriate for impact assessments. We developed guiding principles for designing impact assessments of ecological responses to conservation practices. The guiding principles are as follows: (1) develop the hypothesis first, (2) use replicated experimental designs having controls and treatments, (3) assess the habitat and biological characteristics with quantitative and repeatable sampling methods, (4) use multiple sampling techniques for collecting aquatic organisms, and (5) standardize sampling efforts for aquatic organisms. The guiding principles were applied in designing a study intended to evaluate the influence of herbaceous riparian buffers on channelized headwater streams in central Ohio. Our example highlights that the application of our recommendations will result in impact assessments that are hypothesis‐driven and incorporate quantitative methods for the measurement of abiotic and biotic attributes. 相似文献
230.
Sociological critiques of scientific research processes and their application have developed nuanced understandings of the social, cultural and political forces shaping relationships between science and decision-making. Simultaneously, environmental researchers have sought to construct more engaged, dynamic modes of conducting research to facilitate the application of science in decision-making and action. To date, however, there are relatively few theoretically-oriented approaches that have been able to draw productive connections between the sociological critique and the practical applications that can aid in navigating this complex and diverse milieu. In this article, we propose that the concept of “knowledge governance” can bring together targeted inquiry into the socio-political context in which environmental science is situated, alongside analysis of specific interventions that change knowledge-to-action relationships. Drawing together Jasanoff’s (2005) concept of civic epistemology with Cash et al.’s (2003) knowledge systems for sustainability approach, this knowledge governance inquiry framework offers an integrative lens through which to critically reflect on knowledge-based processes, and incorporate that deeper understanding into intervention efforts. We briefly illustrate its application with reference to a pilot project examining conservation decision-making in the Western Pacific island nation of Palau. 相似文献