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51.
Skinner JR 《Disasters》1990,14(1):55-62
Recent drought in the Sahel has focussed attention on the important role played by natural resources in the rural economy and, together with the increasing environmental awareness of donors, has spawned a series of field projects aimed at improving the management of existing natural resources. This paper is a working document; a contribution to the discussion of how to evaluate the success or failure of natural resource management projects and of whether important components of successful projects can be replicated elsewhere. 相似文献
52.
Behavioral Ecology and Sociobiology - Shared behavioural traits result from the interaction of two or more individuals, making it difficult to discern which individual is in control of the... 相似文献
53.
Pagsuyoin Sheree A. Salcedo Gustavo Santos Joost R. Skinner Christopher B. 《The Environmentalist》2022,42(3):350-361
Environment Systems and Decisions - In this paper, we analyzed the association among trends in COVID-19 cases, climate, air quality, and mobility changes during the first and second waves of the... 相似文献
54.
Adaptation options in agriculture to climate change: a typology 总被引:9,自引:0,他引:9
Adaptation in agriculture to climate change is important for impact andvulnerability assessment and for the development of climate change policy. A wide variety of adaptation options has been proposed as having thepotential to reduce vulnerability of agricultural systems to risks related toclimate change, often in an ad hoc fashion. This paper develops atypology of adaptation to systematically classify and characterize agriculturaladaptation options to climate change, drawing primarily on the Canadiansituation. In particular, it differentiates adaptation options in agricultureaccording to the involvement of different agents (producers, industries,governments); the intent, timing and duration of employment of theadaptation; the form and type of the adaptive measure; and the relationshipto processes already in place to cope with risks associated with climatestresses. A synthesis of research on adaptation options in Canadianagriculture identifies four main categories: (i) technological developments,(ii) government programs and insurance, (iii) farm production practices,and (iv) farm financial management. In addition to these `directadaptations', there are options, particularly information provision, that maystimulate adaptation initiatives. The results reveal that most adaptationoptions are modifications to on-going farm practices and public policydecision-making processes with respect to a suite of changing climatic(including variability and extremes) and non-climatic conditions (political,economic and social). For progress on implementing adaptations to climatechange in agriculture there is a need to better understand the relationshipbetween potential adaptation options and existing farm-level andgovernment decision-making processes and risk management frameworks. 相似文献
55.
Sasha Skinner Philip DeKoninck Kelly Crossley Benjamin Amberg Jan Deprest Stuart Hooper Ryan Hodges 《黑龙江环境通报》2018,38(13):983-993
Partial amniotic carbon dioxide insufflation (PACI) involves insufflating the amniotic sac with carbon dioxide (CO2) and, in some cases, draining some of the amniotic fluid. The creation of a gaseous intra-amniotic compartment improves visualization, even in the presence of limited bleeding, and creates the work space required for complex fetoscopic procedures. Clinically, PACI is mostly used to perform fetoscopic myelomeningocele (MMC) repair, enabling a minimally invasive alternative to open fetal surgery. However, evidence of the fetal safety of PACI is limited. Previous animal experiments in sheep demonstrate that PACI induces fetal hypercapnia and acidosis with largely unknown short and longer term implications. In this review, we examine the literature for the physiological effects of intrauterine insufflation pressure, duration, humidity, and the role of maternal hyperventilation on fetal physiology and well-being. 相似文献
56.
Relationships among Isolated Wetland Size, Hydroperiod, and Amphibian Species Richness: Implications for Wetland Regulations 总被引:6,自引:0,他引:6
Joel W. Snodgrass †‡ Mark J. Komoroski † A. Lawrence Bryan JR. † Joanna Burger 《Conservation biology》2000,14(2):414-419
Abstract: Wetland development within the United States is regulated primarily by size. Decisions concerning wetland destruction or conservation are therefore based in part on three inherent assumptions: (1) small wetlands contain water for short portions of the year; (2) small wetlands support few species; and (3) species found in small wetlands are also found in larger wetlands. We tested these assumptions using data on wetland size, relative hydroperiod (drying scores), and relative species richness of amphibians in depression wetlands of the southeastern United States. We found a significant (p = 0.03) but weak (r2 = 0.05) relationship between hydroperiod and wetland size and no relationship (p = 0.48) between amphibian species richness and wetland size. Furthermore, synthetic models of lentic communities predict that short-hydroperiod wetlands support a unique group of species. Empirical investigations support this prediction. Our results indicate that hydroperiod length should be included as a primary criterion in wetland regulations. We advocate a landscape approach to wetlands regulation, focused in part on conserving a diversity of wetlands that represent the entire hydroperiod gradient. 相似文献
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59.
TIMOTHY J. SMYSER SCOTT A. JOHNSON L. KRISTEN PAGE CASSIE M. HUDSON OLIN E. RHODES JR. 《Conservation biology》2013,27(4):752-762
Translocations are an important tool for wildlife conservation, although progress in the field of reintroduction biology has been hindered by the ad hoc and opportunistic nature of many translocations. We used an experimental translocation to elucidate the role of raccoon roundworm (Baylisascaris procyonis) and inbreeding depression in the decline of the Allegheny woodrat (Neotoma magister), an endangered species. We translocated woodrats from genetically diverse populations in the core of the species range to 4 previously occupied sites (reintroductions) and 2 sites supporting genetically depauperate populations (reinforcements) in Indiana (U.S.A.). In 2 reintroduction sites and 1 reinforcement site, we distributed anthelmintic baits to passively deworm raccoons and reduce the risk of woodrat exposure to roundworms. The remaining sites served as controls. We used raccoon latrine surveys and fecal flotation to monitor temporal variability in roundworm prevalence and effect of treatment. We used live trapping and microsatellite genotyping to monitor the demographic and genetic response of translocated populations over the following 54 months. At the conclusion of the study, 4 of 6 translocations were successfully maintaining abundance through local recruitment. The distribution of anthelmintic baits reduced levels of roundworm contamination, but levels of contamination were also low in 2 of 3 control sites. Reintroductions failed at control sites, one of which was due to high roundworm exposure. The other failed control reintroduction was likely attributable to demographic stochasticity and limited reproductive potential following initial mortality within the first 4 months. In both control and treatment reinforcements, increases in both allelic richness and heterozygosity were accompanied by increases in abundance, which is suggestive of genetic rescue. Our results demonstrate that mitigation of roundworm exposure through the distribution of anthelmintic baits can facilitate woodrat recovery and that diversity within genetically depauperate populations can be restored through the introduction of a limited number of individuals. El Uso de Reubicaciones Experimentales de Neotoma magister para Descifrar Agentes Causales de Disminución 相似文献
60.
Women and Wildlife in Southern Africa 总被引:4,自引:0,他引:4
MALCOLM L. HUNTER JR. ROBERT K. HITCHCOCK BARBARA WYCKOFF-BAIRD† 《Conservation biology》1990,4(4):448-451