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1.
THERON MORGAN‐BROWN SUSAN K. JACOBSON KENNETH WALD BRIAN CHILD 《Conservation biology》2010,24(2):563-572
Abstract: Scientific understanding of the role of development in conservation has been hindered by the quality of evaluations of integrated conservation and development projects. We used a quasi‐experimental design to quantitatively assess a conservation and development project involving commercial butterfly farming in the East Usambara Mountains of Tanzania. Using a survey of conservation attitudes, beliefs, knowledge, and behavior, we compared 150 butterfly farmers with a control group of 170 fellow community members. Due to the nonrandom assignment of individuals to the two groups, we used propensity‐score matching and weighting in our analyses to control for observed bias. Eighty percent of the farmers believed butterfly farming would be impossible if local forests were cleared, and butterfly farmers reported significantly more participation in forest conservation behaviors and were more likely to believe that conservation behaviors were effective. The two groups did not differ in terms of their general conservation attitudes, attitudes toward conservation officials, or knowledge of conservation‐friendly building techniques. The relationship between butterfly farming and conservation behavior was mediated by dependency on butterfly farming income. Assuming unobserved bias played a limited role, our findings suggest that participation in butterfly farming increased participation in conservation behaviors among project participants because farmers perceive a link between earnings from butterfly farming and forest conservation. 相似文献
2.
Various approaches have been used to classify large geographical areas into smaller regions of similar water quality or extrapolate
water-quality data from a few streams to other unmonitored streams. A combination of some of the strengths of existing techniques
is used to develop a new approach for these purposes. In this new approach, referred to here as SPARTA (SPAtial Regression-Tree
Analysis), environmental characteristics for each monitored stream are first quantified using a Geographic Information System
(GIS) and then regression-tree analysis is used to determine which characteristics are most statistically important in describing
the distribution of a specific water-quality constituent. GIS coverages of only the most statistically significant environmental
characteristics are then used to subdivide the area of interest into relatively homogeneous environmental water-quality zones.
Results from the regression-tree analysis not only define the most important environmental characteristics, but also describe
how to subdivide the coverage of the specific characteristic (for example, areas with <26% or ≥26% soil clay content). The
resulting regionalization scheme is customized for each water-quality constituent based on the environmental characteristics
most statistically related to that constituent. SPARTA was used to delineate areas of similar phosphorus, nitrogen, and sediment
concentrations (by including land-use characteristics) and areas of similar potential water quality (by excluding land-use
characteristics). The SPARTA approach reduced the variability in water-quality concentrations (phosphorus, total nitrogen,
Kjeldahl nitrogen, and suspended sediment) within similarly classified zones from that obtained using the US Environmental
Protection Agency's nutrient ecoregions. 相似文献
3.
The Novel and Endemic Pathogen Hypotheses: Competing Explanations for the Origin of Emerging Infectious Diseases of Wildlife 总被引:7,自引:0,他引:7
LARA J. RACHOWICZ‡‡ JEAN-MARC HERO†‡ ROSS A. ALFORD§ JOHN W. TAYLOR JESS A.T. MORGAN VANCE T. VREDENBURG† JAMES P. COLLINS†† CHERYL J. BRIGGS 《Conservation biology》2005,19(5):1441-1448
Abstract: Chytridiomycosis, caused by the fungal pathogen Batrachochytrium dendrobatidis , is an emerging infectious disease implicated in declines of amphibian populations around the globe. An emerging infectious disease is one that has recently been discovered; has recently increased in incidence, geography, or host range; or is newly evolved. For any given outbreak of an emerging disease, it is therefore possible to state two hypotheses regarding its origin. The novel pathogen hypothesis states that the disease has recently spread into new geographic areas, whereas the endemic pathogen hypothesis suggests that it has been present in the environment but recently has increased in host range or pathogenicity. Distinguishing between these hypotheses is important, because the conservation measures needed to slow or stop the spread of a novel pathogen are likely to differ from those needed to prevent outbreaks of an endemic pathogen. Population genetics may help discriminate among the possible origins of an emerging disease. Current evidence suggests chytridiomycosis may be a novel pathogen being spread worldwide by carriers; until we know how much genetic variation to expect in an endemic strain, however, we cannot yet conclude that B. dendrobatidis is a novel pathogen. 相似文献
4.
Abstract: Some conservationists argue for a focused effort to protect the most critically endangered species, and others suggest a large‐scale endeavor to safeguard common species across large areas. Similar arguments are applicable to the distribution of scientific effort among species. Should conservation scientists focus research efforts on threatened species, common species, or do all species deserve equal attention? We assessed the scientific equity among 1909 mammals, birds, reptiles, and amphibians of southern Africa by relating the number of papers written about each species to their status on the International Union for Conservation of Nature Red List. Threatened large mammals and reptiles had more papers written about them than their nonthreatened counterparts, whereas threatened small mammals and amphibians received less attention than nonthreatened species. Threatened birds received an intermediate amount of attention in the scientific literature. Thus, threat status appears to drive scientific effort among some animal groups, whereas other factors (e.g., pest management and commercial interest) appear to dictate scientific investment in particular species of other groups. Furthermore, the scientific investment per species differed greatly between groups—the mean number of papers per threatened large mammal eclipsed that of threatened reptiles, birds, small mammals, and amphibians by 2.6‐, 15‐, 216‐, and more than 500‐fold, respectively. Thus, in the eyes of science, all species are not created equal. A few species commanded a great proportion of scientific attention, whereas for many species information that might inform conservation is virtually nonexistent. 相似文献
5.
Evaluation of a Market in Wetland Credits: Entrepreneurial Wetland Banking in Chicago 总被引:1,自引:0,他引:1
Abstract: With the rise of market‐led approaches to environmental policy, compensation for permitted discharge of dredge or fill material into wetlands under Section 404 of the U.S. Clean Water Act has been purchased increasingly from entrepreneurial third‐party providers. The growth of this practice (i.e., entrepreneurial wetland banking) has resolved many challenges associated with wetland compensation. But it has also produced (1) quantifiable temporal loss of wetland ecological functions, (2) spatial redistribution of wetland area, and (3) a degree of regulatory instability that may pose a threat to entrepreneurial compensation as a sustainable component of wetland‐compensation policy. We used achieved compensation ratios, lapse between bank credit sale and the attainment of performance standards, distance between impact and bank site, and changes in bank market area to examine these 3 factors. We analyzed data from a census of all such transactions in the Chicago District of the U.S. Army Corps of Engineers, compiled from site visits, Corps databases, and contacts with consultants and Section 404 permittees. Entrepreneurial banking provided compensation at a lower overall ratio than nonbank forms of compensation. Approximately 60% of bank credits were sold after site‐protection standards were met but before ecological performance standards were met at the bank site. The average distance between bank and impact site was approximately 26 km. The area of markets within which established banks can sell wetland credits has fluctuated considerably over the study period. Comparing these data with similar data for other compensation mechanisms will assist in evaluating banking as an element of conservation policy. Data characterizing the performance of entrepreneurial wetland banks in actual regulatory environments are scarce, even though it is the most established of similar markets that have become instrumental to federal policy in administering several major environmental protection laws. 相似文献
6.
MICHAEL A. MCCARTHY ALANA L. MOORE JOCHEN KRAUSS JOHN W. MORGAN CHRISTOPHER F. CLEMENTS 《Conservation biology》2014,28(6):1575-1583
Biodiversity indices often combine data from different species when used in monitoring programs. Heuristic properties can suggest preferred indices, but we lack objective ways to discriminate between indices with similar heuristics. Biodiversity indices can be evaluated by determining how well they reflect management objectives that a monitoring program aims to support. For example, the Convention on Biological Diversity requires reporting about extinction rates, so simple indices that reflect extinction risk would be valuable. We developed 3 biodiversity indices that are based on simple models of population viability that relate extinction risk to abundance. We based the first index on the geometric mean abundance of species and the second on a more general power mean. In a third index, we integrated the geometric mean abundance and trend. These indices require the same data as previous indices, but they also relate directly to extinction risk. Field data for butterflies and woodland plants and experimental studies of protozoan communities show that the indices correlate with local extinction rates. Applying the index based on the geometric mean to global data on changes in avian abundance suggested that the average extinction probability of birds has increased approximately 1% from 1970 to 2009. Conectando Índices para el Monitoreo de la Biodiversidad con la Teoría de Riesgo de Extinción 相似文献
7.
David Gibbs∗ James Longhurst† Clare Braithwaite‡ 《Journal of Environmental Planning and Management》1996,39(3):317-332
The recent growth of interest in sustainable development has led to the incorporation of the concept into policy making at a variety of scales. In all cases particular emphasis is placed upon the local scale as the focus for the implementation of policy and initiatives and especially upon local authorities as the major contributor to this process. There has been little assessment, however, of the extent to which local authorities either can, or are, undertaking such initiatives. This paper examines: the potential role that local authorities can play in integrating economic development and the environment; the forms of response and initiatives that are currently in place, drawing upon survey evidence from urban local authorities in England and Wales; and some of the limits to local authority action. 相似文献
8.
Volunteer Environmental Monitoring and the Role of the Universities: The Case of Citizens' Environment Watch 总被引:1,自引:0,他引:1
Universities can provide a stable home for launching collaborative community research projects. Citizens' Environment Watch
(CEW), an environmental monitoring initiative based at the University of Toronto, has made significant contributions to environmental
education and stewardship in Ontario, Canada. Following dramatic cuts in provincial monitoring programs, citizens and youth
have used chemical parameters and biological indicators to gauge water and air quality, and to identify areas requiring remediation
and pollution prevention efforts. The relationship of Citizens' Environment Watch to government agencies, funders and other
grassroots environmental groups has evolved over the past 5 years as CEW attempts to remain effective without taking on the
investigative and enforcement roles to support the regulatory enforcement that has been largely abandoned by government. We
explore the challenges inherent in developing and maintaining a volunteer organization that carries out rigorous and useful
scientific work and we outline the ability of a university to help overcome these critical challenges. Finally, we present
lessons learned for the benefit of other citizen and youth monitoring projects. 相似文献
9.
This study was conducted to examine adsorption of pesticides bifenthrin, carbosulfan, λ-cyhalothrin, cypermethrin, endosulfan, parathion methyl, monocrotophos and 4-nitrophenol by sandy clay loam (S.C.L) and sandy loam (S.L) soils (with varying organic content). There was no significant difference between the observed soil water partitioning coefficient values (K d) derived from linear and nonlinear Freundlich isotherms. Adsorption of pesticides on S.C.L soils was higher than those on S.L soils. K d values showed significant correlations (r 2?=?0.8???0.99 and 0.65???0.97) with soil organic carbon content (OC) and weak correlations (r 2?=?0.2???0.29 and 0.1???0.18) with clay contents of S.C.L and S.L soil at p?≤?0.05, respectively for all pesticides (except monocrotophos). Observed K oc values (soil-water partitioning constants based on the organic C fraction of the soil) were in accordance with the literature values of Wauchope and Tomlin with a maximum deviation of less than 0.5 log units. Ten Quantitative Property-Property Relationships (QPPR) among water solubility, n-octanol water coefficient (K ow) and K oc were proposed for studied pesticides except monocrotophos. The models were considered acceptable when predicted-observed difference for log?K ow and log?K oc were ≤?0.3 and ≤?0.5?log units, respectively, during the validation procedure. This work indicates that the log?K oc derived from the log Kow, from some of existing relationships, may be a fair predictor where observed values (i.e., K d and K oc) are not available. Furthermore, predicted leaching potential by groundwater ubiquity scores (GUS) equation was solved by using observed K oc values and literature reported half lives of pesticides. GUS ranked the mobility of nonvolatile compounds i.e., bifenthrin, λ-cyhalothrin, cypermethrin and endosulfan extremely low; methyl parathion very low; 4-nitrophenol low; carbofuran and monocrotophos very high in S.C.L and S.L soils, respectively. Results discussed in this paper provide background to prioritize pesticides or chemical groups that should be evaluated under field conditions with regard to their leaching potential to groundwater in arid climates. 相似文献
10.