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221.
Techniques and Guidelines for Monitoring Neotropical Butterflies 总被引:11,自引:0,他引:11
Helen R. Sparrow Thomas D. Sisk Paul R. Ehrlich Dennis D. Murphy 《Conservation biology》1994,8(3):800-809
Long-term monitoring of selected species can identify changes in biological diversity, permitting the timely adjustment of management activities to reverse or avoid undesired trends. This paper addresses several related issues bearing on the development of inexpensive and easily implemented monitoring programs for tropical butterflies. First, we discuss the use of butterflies as ecological indicators. Next, we present field evaluations of butterfly sampling techniques, indicating that: (1) light-gap size greatly affects sampling results in forests and should be of critical concern in site selection and sampling design; (2) baited traps and visual censuses provide complementary data on butterfly abundances; (3) monitoring a subset of locally common butterfly species can provide data for comparing community composition and relative abundance of species in areas where species inventories are incomplete. Drawing on these results, we develop guidelines for designing monitoring programs. These address the formulation of explicit questions to be addressed through monitoring and the selection of appropriate study sites, study species, sampling techniques, and sampling frequency. A protocol for the ongoing butterfly monitoring program that emerged from these studies is appended. The techniques and guidelines presented here are intended to serve as an adaptable model for biologists designing monitoring projects to help guide applied conservation efforts in the tropics. 相似文献
222.
When an organization embarks on the path of environmental leadership, how does it track and quantify its efforts? This article describes a system for identifying, tracking, and communicating environmental efforts. 1 Anita Wolfe wishes to recognize Richard P. Wells'S article, “Point of View: Environmental Management in Mexico,” TQEM, Vol. 2, No. 3, as an invaluable source in helping to develop this system. In addition, it examines the experience of Ontario Hydro, Canada'S largest public utility, within a similar framework. 相似文献
223.
Helen Rendell 《Environmental management》1985,9(4):289-301
In this study, the damage caused to one small hilltop town by the southern Italian earthquake of November 1980 is considered in detail. Tricarico, although peripheral to the epicenter zone, was gravely damaged. The distribution of damaged properties within the historic center of the town is described and analyzed. The geological and socioeconomic factors contributing to the pattern of damage are discussed and the problems associated with reconstruction are considered. 相似文献
224.
Natural areas of national parks constitute unique ecological and aesthetic resources. Since the inception of national parks, it has been apparent that they are susceptible to threats that result in significant change and damage. Today, major issues concerning management of parks relate to questions of expanded visitor use and what types of facilities are to be deemed appropriate, that is, the dilemma of preservation versus use. In the United States of America, resolution of this dilemma must, strictly speaking, be based upon intent and meaning of Congressional legislation. The traditional interpretation of legislation in the U.S. has been to provide for a balance of use and preservation. However, extensive review of the literature of national park policy reveals a remarkable lack of elaboration and clarification of legislative meaning. Based upon a critical analysis of pertinent legislation, which has heretofore been ignored, we provide an interpretation of legislative meaning which strongly supports a policy of preservation of park resources. 相似文献
225.
Stout JH Trust KA Cochrane JF Suydam RS Quakenbush LT 《Environmental pollution (Barking, Essex : 1987)》2002,119(2):215-226
Population declines in four species of eider; common (Somateria mollissima), king (Somateria spectabilis), spectacled (Somateria fischeri) and Steller's (Polysticta stelleri), have raised concerns about exposure to contaminants. Livers and kidney tissues were collected from eiders in Alaska and Russia for organic and elemental analyses. Results showed that organochlorine and many elemental levels were below toxic thresholds; however, in many cases, cadmium, copper, lead and serenium appeared high relative to other waterfowl and may warrant concern. With the exception of lead, local anthropogenic sources for these elements are not known. Although adverse physiological responses have not been documented in eiders, these four elements cannot be ruled out as contaminants of potential concern for some eider species. 相似文献
226.
Matthew Gronquist Frank C. Schroeder Helen Ghiradella David Hill Erin M. McCoy Jerrold Meinwald Thomas Eisner 《Chemoecology》2006,16(1):39-43
Summary. Lucidota atra, a diurnal firefly, shares possession of defensive steroids (lucibufagins or LBGs) with nocturnal fireflies of the genus
Photinus. Photinus are protected against predators by their LBGs, but not against fireflies of the genus Photuris, the so-called firefly femmes fatales, which prey upon Photinus, thereby acquiring LBGs for their own defense. We propose that L. atra may have been prompted evolutionarily to become diurnal by the opportunity to avoid, thereby, being hunted by Photuris. Indeed, L. atra, if offered to Photuris, were eagerly devoured by the latter, which sequestered their LBG’s. In feeding on L. atra, Photuris may be driven by a gustatory affinity for LBGs. Persistent nocturnality might therefore have put L. atra at risk vis à vis Photuris. Diurnality freed the firefly from that risk, without compromising its defended status with respect to other predators. Possession
of LBGs may in fact account for L. atra’s unacceptability to birds and spiders. 相似文献
227.
228.
Helen Ingram 《Journal of the American Water Resources Association》1972,8(6):1177-1188
A set of decision rules have governed the traditional politics of water development. This paper identifies these rules, describes their operation, and explains the logic behind their adoption. Personal interviews with a large number of decision makers are cited to substantiate and illustrate particular rules. There are five decision rules: local support, agreement, mutual accommodation, mutual noninterference, and fairness and equity. These guidelines are intended to insure support, lessen conflict, and protect the reputation of water development as a worthwhile federal investment. Since there are current indications that the traditional decision rules are no longer followed, the paper aims to identify why and how the rules are changing. 相似文献
229.
Nina Bhola Helen Klimmek Naomi Kingston Neil D. Burgess Arnout van Soesbergen Colleen Corrigan Jerry Harrison Marcel T. J. Kok 《Conservation biology》2021,35(1):168-178
During 2021, Parties to the Convention on Biological Diversity (CBD) are expected to meet in Kunming, China, to agree on a new global biodiversity framework aimed at halting and reversing biodiversity loss, encouraging the sustainable use of biodiversity, and ensuring the equitable sharing of its benefits. As the post-2020 global biodiversity framework evolves, parties to the convention are being exposed to a range of perspectives on the conservation and sustainable use of biodiversity, relating to the future framework as a whole or to aspects of it. Area-based conservation measures are one such aspect, and there are diverse perspectives on how new targets might be framed in relation to these measures. These perspectives represent different outlooks on the relationship between human and nonhuman life on Earth. However, in most cases there is a lack of clarity on how they would be implemented in practice, the implications this would have for biodiversity and human well-being, and how they would contribute to achieving the 2050 Vision for Biodiversity of “living in harmony with nature.” We sought to clarify these issues by summarizing some of these perspectives in relation to the future of area-based biodiversity conservation. We identified these perspectives through a review of the literature and expert consultation workshops and compiled them into 4 main groups: Aichi+, ambitious area-based conservation perspectives, new conservation, and whole-earth conservation. We found that although the perspectives Aichi+ and whole earth are in some cases at odds with one another, they also have commonalities, and all perspectives have elements that can contribute to developing and implementing the post-2020 global biodiversity framework and achieving the longer term CBD 2050 Vision. 相似文献
230.