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101.
Andrew P.Zemek 《生态毒理学报》2003,25(1):53-55
在联合国环境规划署、世界银行集团和采矿、矿产和可持续发展计划( MMSD)一起组织的关注金融机构在为采矿项目提供资金方面作用的研讨会之前,对采矿业投资过程中的关键决策者进行了采访.本文提供了给采矿业提供投资的金融机构对当前环境状态的印象. 相似文献
102.
J. Andrew Grant Dianne Balraj Georgia Mavropoulos‐Vagelis 《Natural resources forum》2013,37(4):269-279
International forestry governance is an integral part of the global policy debates on how to prevent deforestation, illicit extraction, and unsustainable timber practices. Africa is an important producer of timber, yet the region is beset by a lack of capacity and other governance challenges in the management of its forestry sector. We employ a network governance analysis to examine the extent to which the evolution and operation of the Forest Stewardship Council (FSC) and la Commission des Forêts d'Afrique Centrale (COMIFAC) have addressed governance challenges. We assess the strengths and weaknesses of these two leading examples of international forestry governance by introducing recent evidence and insights from Africa. We conclude with a policy‐relevant discussion of how the FSC and COMIFAC might enhance authority, legitimacy, and effectiveness and improve forestry governance in Africa and other parts of the world. 相似文献
103.
Andrew D. M. Dobson E. J. Milner-Gulland Colin M. Beale Harriet Ibbett Aidan Keane 《Conservation biology》2019,33(3):665-675
The threat posed to protected areas by the illegal killing of wildlife is countered principally by ranger patrols that aim to detect and deter potential offenders. Deterring poaching is a fundamental conservation objective, but its achievement is difficult to identify, especially when the prime source of information comes in the form of the patrols’ own records, which inevitably contain biases. The most common metric of deterrence is a plot of illegal activities detected per unit of patrol effort (CPUE) against patrol effort (CPUE-E). We devised a simple, mechanistic model of law breaking and law enforcement in which we simulated deterrence alongside exogenous changes in the frequency of offences under different temporal patterns of enforcement effort. The CPUE-E plots were not reliable indicators of deterrence. However, plots of change in CPUE over change in effort (ΔCPUE-ΔE) reliably identified deterrence, regardless of the temporal distribution of effort or any exogenous change in illegal activity levels as long as the time lag between patrol effort and subsequent behavioral change among offenders was approximately known. The ΔCPUE-ΔE plots offered a robust, simple metric for monitoring patrol effectiveness; were no more conceptually complicated than the basic CPUE-E plots; and required no specialist knowledge or software to produce. Our findings demonstrate the need to account for temporal autocorrelation in patrol data and to consider appropriate (and poaching-activity-specific) intervals for aggregation. They also reveal important gaps in understanding of deterrence in this context, especially the mechanisms by which it occurs. In practical applications, we recommend the use of ΔCPUE-ΔE plots in preference to other basic metrics and advise that deterrence should be suspected only if there is a clear negative slope. Distinct types of illegal activity should not be grouped together for analysis, especially if the signs of their occurrence have different persistence times in the environment. 相似文献
104.
In April, July and August 1989 and February 1990, the delta region of the Fly River was surveyed to establish the aerial extent of mangrove forests, their species composition, tree densities and basal areas, and potential net primary production. Mangrove forests cover 87 400 ha, mainly on islands within the delta. Twentynine mangrove plant species were recorded, but there were only three major forest types in the delta.Rhizophora apiculata-Bruguiera parviflora forests (hereafterRhizophora-Bruguiera forests) predominated in regions where river water salinities were >10. These forests covered 31 500 ha and had mean total tree densities and basal areas of 2027 stems ha–1 and 21 m2 ha–1, respectively. Forests of the palmNypa fruticans (hereafterNypa forests) covered 38 400 ha, mainly in regions where river salinities were ~1 to 10, and had mean total densities and basal areas of 4431 stems ha–1 and 38 m2 ha–1, respectively. Forests dominated byAvicennia marina and/orSonneratia lanceolata (hereafterAvicennia-Sonneratia forests) predominated on accreting banks of sediment and covered 17 500 ha. In very low-salinity (< 1) regions there are large monospecific stands ofS. lanceolata. Mean total densities and basal areas forAvicennia-Sonneratia forests were 7036 stems ha–1 and 22 m2 ha–1, respectively. Mean net primary productivity (kg C ha–1 d–1) was estimated to be 26.7, 27.1 and 19.0 forRhizophora-Bruguiera, Nypa andAvicennia-Sonneratia forests, respectively. Total daily net primary production by all mangrove forests was estimated at 2214 t carbon. Using assumptions based on work in tropical Australia, it was estimated that ~678 t carbon (or 31% of primary production) were exported daily from mangrove forests to the waters of the delta.Contribution No. 550 from the Australian Institute of Marine Science 相似文献
105.
A single population of short-beaked common dolphins (Delphinus delphis Linnaeus) occurs in the western North Atlantic from Florida to Newfoundland. Dolphins killed in a swordfish driftnet fishery
between 1989 and 1998 provided samples for the present study. These were combined with additional observations from carcasses
collected from stranding programs. Samples were examined from 74 female and 161 male short-beaked common dolphins. A highly
significant male bias in the sex ratio of both the bycatch and stranding samples suggests that sex-based habitat partitioning
or school segregation occurs in this population. Age was estimated from decalcified thin sections of teeth and testis and
ovarian samples were examined both macro- and microscopically. Analyses showed that reproduction was both seasonal and synchronized.
Females reached sexual maturation at approximately age eight; males matured at 9.5 years. Conception occurred during July
and August (mean day 24 July). Gestation was estimated to last just under a year, so most females gave birth during July and
August (mean day 15 July). Annual pregnancy rate was estimated to be between 25 and 33%. Males undergo a fivefold seasonal
increase in testes mass and a twofold increase in seminiferous tubule diameter. Peak sperm production potential was observed
in July. At the end of the breeding season testis size and activity decreased after August. Male dolphins in this population
are hypothesized to engage in some form of sperm competition. 相似文献
106.
Correlates of female choice in resource-defending antelope 总被引:2,自引:0,他引:2
Summary Where males offer their mates assistance in rearing offspring as well as access to defended resources, female mate choice should be influenced by both male phenotype and resource quality. In contrast, where there is no paternal care the relative importance of choice for male and territory traits is less well understood. We looked at female distribution across male territories in order to assess mate choice criteria in puku Kobus vardoni, and topi Damaliscus lunatus, two antelope where males defend resources but are not involved in parental care. In both species female distribution was correlated with male phenotype as well as the quality of forage and risk of predation on different territories. Male and territory characteristics were intercorrelated, but statistical analysis revealed that male traits, forage quality and predation risk were all significant, independent predictors of female choice in both study species. This is the first demonstration that female choice in mammals might be simultaneously influenced by male phenotype as well as the quality of defended resources.Correspondence to: A. Balmford 相似文献
107.
Identifying natural and anthropogenic sources of metals in urban and rural soils using GIS-based data,PCA, and spatial interpolation 总被引:2,自引:0,他引:2
Harley T. Davis C. Marjorie Aelion Suzanne McDermott Andrew B. Lawson 《Environmental pollution (Barking, Essex : 1987)》2009,157(8-9):2378-2385
Determining sources of neurotoxic metals in rural and urban soils is important for mitigating human exposure. Surface soil from four areas with significant clusters of mental retardation and developmental delay (MR/DD) in children, and one control site were analyzed for nine metals and characterized by soil type, climate, ecological region, land use and industrial facilities using readily available GIS-based data. Kriging, principal component analysis (PCA) and cluster analysis (CA) were used to identify commonalities of metal distribution. Three MR/DD areas (one rural and two urban) had similar soil types and significantly higher soil metal concentrations. PCA and CA results suggested that Ba, Be and Mn were consistently from natural sources; Pb and Hg from anthropogenic sources; and As, Cr, Cu, and Ni from both sources. Arsenic had low commonality estimates, was highly associated with a third PCA factor, and had a complex distribution, complicating mitigation strategies to minimize concentrations and exposures. 相似文献
108.
G.?BernardiEmail author G.?Bucciarelli D.?Costagliola D.?R.?Robertson J.?B.?Heiser 《Marine Biology》2004,144(2):405-375
Wrasses in the genus Thalassoma comprise 27 recognized species that occur predominantly on coral reefs and subtropical rocky reefs worldwide. The phylogenetic relationships for 26 species were examined based on two mitochondrial genes (cytochrome b and 16S rRNA) and one nuclear intron (the first intron of the ribosomal protein S7). Two closely related species, the bird-wrasses (Gomphosus varius Lacepède, 1801 and G. caerulaeus Lacepède, 1801), were also included in the analysis. These species grouped within the genus Thalassoma. Thalassoma newtoni (Osório, 1891) from Sao Tome, which is generally synonymized with the Atlantic/Mediterranean Thalassoma pavo (Linnaeus, 1758) appears to be a valid species. Using a molecular clock, the genus was estimated to have originally diverged 8–13 million years ago, with Thalassoma ballieui (Vaillant and Sauvage, 1875) from Hawaii and Thalassoma septemfasciata Scott, 1959 from Western Australia as the ancestral species. Approximately 5–10 million years ago, a sudden burst of speciation resulted in seven clades, which were resolved with the sequence data. The terminal Tethyan event and the closing of the Isthmus of Panama were probably the major historical factors shaping the evolution of species in the genus Thalassoma. These data on the spatio-temporal pattern of speciation in the Indo-Pacific indicate that peripheral species have been generated at various times throughout the history of the genus, and that none of the widespread species are relatively young. Thus, there is no clear support for centrifugal (youngest at the periphery) versus centripetal (oldest at the periphery) modes of generation of species, two theories which have been used to account for geographic gradients in species diversity.Electronic Supplementary Material Supplementary material is available in the online version of this article at http://dx.doi.org/10.1007/s00227-003-1199-0.An erratum to this article can be found at
Communicated by J.P. Grassle, New Brunswick 相似文献
109.
Ibrahim Adham Taib Andrew S McIntosh Carlo Caponecchia Melissa T. Baysari 《Safety Science》2012,50(9):1801-1805
Medical error taxonomies are used to report and analyse patient safety incidents. Medical error taxonomies can be generic or domain-specific. In comparing generic and domain-specific medical error taxonomies, the literature compares the information both type of taxonomies classify. There is little evidence the taxonomies have been compared in terms of usability and reliability. Twenty nurses and 21 pharmacists participated in a study comparing the usability and reliability of a generic medical error taxonomy and a medication error taxonomy. The medical error taxonomies utilized were the Patient Safety Event Taxonomy and the NCC MERP Taxonomy of Medication Error. The study found no significant difference in the usability ratings of both taxonomies. The taxonomies required different amount of time to classify patient safety incidents and had significantly different reliability levels. The reliability of the NCC MERP Taxonomy of Medication Error was significantly different when used by nurses and pharmacists. The taxonomy was also preferred by the majority of participants. Some recommendations are made about the design of future medical error taxonomies. 相似文献
110.