From pre-hispanic to future conservation alternatives: lessons from Mexico. (1/2885)

In this paper, we review some past and present trends in biodiversity conservation in Mexico and explore possible explanations of why, in spite of this long history of depredation and ineffective conservation policies, the ecosystems have been able to cope with and retain most of their biological components. We suggest a hypothesis based on the persistence of a complex mosaic of past and present traditional land uses as a possible explanation for this resilience. We propose an agenda for the scope of future conservation research and policy, particularly the need to take the socioeconomic context of environmental degradation into account. We put forth a series of questions that we think need to be investigated if the conservation research community is to participate in developing solutions for the future welfare of the human species and of biodiversity on earth.  (+info)

Gardenification of tropical conserved wildlands: multitasking, multicropping, and multiusers. (2/2885)

Tropical wildlands and their biodiversity will survive in perpetuity only through their integration into human society. One protocol for integration is to explicitly recognize conserved tropical wildlands as wildland gardens. A major way to facilitate the generation of goods and services by a wildland garden is to generate a public-domain Yellow Pages for its organisms. Such a Yellow Pages is part and parcel of high-quality search-and-delivery from wildland gardens. And, as they and their organisms become better understood, they become higher quality biodiversity storage devices than are large freezers. One obstacle to wildland garden survival is that specific goods and services, such as biodiversity prospecting, lack development protocols that automatically shunt the profits back to the source. Other obstacles are that environmental services contracts have the unappealing trait of asking for the payment of environmental credit card bills and implying delegation of centralized governmental authority to decentralized social structures. Many of the potential conflicts associated with wildland gardens may be reduced by recognizing two sets of social rules for perpetuating biodiversity and ecosystems, one set for the wildland garden and one set for the agroscape. In the former, maintaining wildland biodiversity and ecosystem survival in perpetuity through minimally damaging use is paramount, while in the agroscape, wild biodiversity and ecosystems are tools for a healthy and productive agroecosystem, and the loss of much of the original is acceptable.  (+info)

Exposure to airborne microorganisms and volatile organic compounds in different types of waste handling. (3/2885)

Occupational exposure of workers to airborne microorganisms and volatile organic compounds (VOC) in different types of waste treatment situations was examined during summer time. Microorganisms were collected as stationary samples using a six-stage Andersen impactor, while for VOCs both personal and stationary sampling was conducted. The exposure at the waste handling facility was considerably greater than at landfill sites or in waste collection. The concentrations of viable fungi were maximally 10(5) cfu/m3, and the concentrations of both total culturable bacteria and Gram-negative bacteria exceeded the proposed occupational exposure limit values (OELV), being 10(4) and 10(3) cfu/m3, respectively. Exposure to VOCs in the waste handling facility was three times higher than at the landfill sites, being at highest 3000 microg/m3, considered to be the limit for discomfort. The use of personal protective equipment at work, thorough hand washing and changing clothes after the work shift are strongly recommended in the waste handling facility and the landfill sites.  (+info)

Global assessment of deforestation related to tobacco farming. (4/2885)

OBJECTIVES: To assess the global amount of forest and woodland consumed annually for curing tobacco between 1990 and 1995; to estimate tobacco's share in total deforestation; to rank tobacco-growing countries by the degree of impact of tobacco deforestation; and to indicate environmental criticality emerging from tobacco's impact on forest resources. DESIGN: Production of country-specific estimates of forests/woodlands needed and depleted on the basis of growing stock/increment of woody biomass involved and wood consumption of tobacco. Comparison of results with secondary statistics on forest cover, deforestation, and population development. RESULTS: An estimated 200,000 ha of forests/woodlands are removed by tobacco farming each year. Deforestation mainly occurs in the developing world, amounting to 1.7% of global net losses of forest cover or 4.6% of total national deforestation. Environmental criticality exists or is emerging in 35 countries with an estimated serious, high, and medium degree of tobacco-related deforestation, mainly in southern Africa, middle east, south, and east Asia, South America, and the Caribbean. CONCLUSION: The hypothesis that deforestation from tobacco production does not have a significant negative effect has to be challenged. For empirical validation, the globally significant pattern of estimated tobacco-related environmental damage ought to be included in international research agendas on global environmental change, to become an integral and rational part of tobacco control policy.  (+info)

Role of reproductive technologies and genetic resource banks in animal conservation. (5/2885)

In combination with modem reproductive technologies, there is potential to use frozen and stored germplasm (genetic resource banks) to support conservation measures for the maintenance of genetic diversity in threatened species. However, turning this idea into reality is a complex process, requiring interdisciplinary collaboration and clearly defined goals. As the number of species deserving the attention of conservation scientists is overwhelmingly large, yet detailed knowledge of reproductive physiology is restricted to relatively few of them, choosing which species to conserve is one of the most difficult issues to be tackled. Besides the direct application of technologically advanced reproductive procedures, modern approaches to non-invasive endocrine monitoring play an important role in optimizing the success of natural breeding programmes. Through the analysis of urine and faecal samples, this type of technology provides invaluable management information about the reproductive status of diverse species. For example, it is possible to diagnose pregnancy and monitor oestrous cycles in elephants and rhinos without causing stress through restraint for sample collection. In this review, we identify the potential contribution of reproductive biology and genetic resource banks to animal conservation, but also highlight the complexity of issues determining the extent to which this potential can be achieved.  (+info)

Late patency of recycled internal mammary artery: verification by Doppler echocardiography and coronary angiography. (6/2885)

We report the case of a 57-year-old man who had presented with exertional angina early in 1997 and had subsequently undergone myocardial revascularization with the use of both internal mammary arteries. Two months after surgery, the patient was readmitted to the hospital with unstable angina. Coronary angiography revealed a 90% occlusion of the left internal mammary artery anastomosis, which was attached to the left anterior descending coronary artery. At reoperation, the left internal mammary artery was detached from the left anterior descending coronary artery, probed and injected with papaverine, checked for patency, and regrafted to the same coronary artery. Recycling of the left internal mammary artery was facilitated by the harvesting and routing technique that had been used during the previous operation. At the patient's 1-year follow-up visit, both Doppler echocardiography and coronary angiography showed patency of the recycled graft. We conclude that recycling of the left internal mammary artery is a safe and effective option in selected patients who require reoperation after myocardial revascularization.  (+info)

Robustness of reserve selection procedures under temporal species turnover. (7/2885)

Complementarity-based algorithms for the selection of reserve networks emphasize the need to represent biodiversity features efficiently, but this may not be sufficient to maintain those features in the long term. Here, we use data from the Common Birds Census in Britain as an exemplar data set to determine guidelines for the selection of reserve networks which are more robust to temporal turnover in features. The extinction patterns found over the 1981-1991 interval suggest that two such guidelines are to represent species in the best sites where they occur (higher local abundance) and to give priority to the rarer species. We tested five reserve selection strategies, one which finds the minimum representation set and others which incorporate the first or both guidelines proposed. Strategies were tested in terms of their efficiency (inversely related to the total area selected) and effectiveness (inversely related to the percentage of species lost) using data on eight pairs of ten-year intervals. The minimum set strategy was always the most efficient, but suffered higher species loss than the others, suggesting that there is a trade-off between efficiency and effectiveness. A desirable compromise can be achieved by embedding the concerns about the long-term maintenance of the biodiversity features of interest in the complementarity-based algorithms.  (+info)

Subcutaneous atypical mycobacteriosis in captive tiger quolls (Dasyurus maculatus). (8/2885)

From July 1989 to October 1998, 9/37 (24%) adult captive tiger quolls (Dasyurus maculatus) were diagnosed with atypical mycobacterial infection involving the subcutis and skin. Females were more often affected than males (seven females, two males). Grossly, lesions presented as focal thickenings, plaques, and abscesses within the subcutis, often with fistulous tracts. The subcutis and skin overlying cervical and thoracic regions were the primary sites of infection. Cytology of subcutaneous impression smears from all nine affected tiger quolls revealed pyogranulomatous inflammation admixed with several acid-fast bacilli. Histologically, all tiger quolls had nodular to diffuse pyogranulomatous panniculitis and cellulitis. Small numbers of acid-fast bacilli were noted histologically in 7/9 (78%) animals. Skin cultures from seven tiger quolls were positive for one or more different Runyon group IV mycobacteria. The disease described in these tiger quolls is similar to subcutaneous atypical mycobacteriosis of humans and domestic animals.  (+info)