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Wenchao Xue May Zaw Xiaochan An Yunxia Hu Allan Sriratana Tabucanon 《Frontiers of Environmental Science & Engineering》2020,14(2):32
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Implementing effective conservation requires an understanding of factors affecting deforestation and forest degradation. Previous studies have investigated factors affecting deforestation, while few studies have examined the determinants of both of deforestation and forest degradation for more than one period. To address this gap, this study examined factors influencing deforestation and forest degradation during 1989–2000 and 2000–2005 in the Popa Mountain Park, Myanmar. We applied multinomial logistic regression (MNL) using land cover maps derived from Landsat images as the dependent variables as well as spatial and biophysical factors as the independent variables. The MNL models revealed influences of the determinants on deforestation and forest degradation changes over time. For example, during 1989–2000, deforestation from closed forest was positively correlated to the distance from the park boundary and was negatively correlated with distance from villages, roads, the park circular road, slope, western aspect and elevation. On the other hand, during 2000–2005, deforestation of closed forest was positively correlated with distance from villages, roads, the park circular road, slope and western aspect, and negatively correlated with distance from the park boundary and elevation. Similar scenarios were observed for the deforestation of open forest and forest degradation of closed forest. The study also found most of the determinants influenced deforestation and forest degradation differently. The changes in determinants of deforestation and forest degradation over time might be attributable to the general decrease in resource availability and to the effect of conservation measures conducted by the park. 相似文献
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Van Thinh Nguyen Matsumoto Masaru Zaw Myo Kuwahara Yoshihiro Xie Yiping Ozaki Akinori Kurosawa Kiyoshi 《Environmental geochemistry and health》2022,44(10):3249-3263
Environmental Geochemistry and Health - The arsenic-contaminated groundwater has attracted attention in much south and southeast Asian deltas, however, mainly on the deep aquifers. Here, arsenic... 相似文献
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Very little is known of the factors controlling soil-to-plant transfer of radionuclides in tropical environments. As part of an IAEA/FAO coordinated research project (CRP) designed to elucidate some of those factors, near-surface samples of two agricultural red-earth soils (Blain and Tippera) were collected from a study site in the Northern Territory. The climate is tropical monsoonal with crops being grown over the wet season from December to March/April. It is important to understand soil variables that may be related to this dramatic seasonality. In this investigation, soil redox state and microbial populations were assessed before and after the growing season with a view to generating hypotheses for future evaluation. The X-ray absorption near edge structure (XANES) technique was used to determine overall changes in the solid-state redox speciation of Fe and Mn in soils across the growing period. Fe speciation did not change but approximately 10% of the total Mn was oxidised from Mn(II) to Mn(III) and Mn(IV) in both soils between October 1999 and April 2000. An apparent disconnect between Fe and Mn was not unexpected given the >10 times higher concentration of Fe in the soils compared with Mn. These results have implications for the bioavailability of redox sensitive radionuclides such as Tc and Pu. Similarly, microbial population estimates were derived before and after the growing period. Total bacterial populations did not vary from 10(6) to 10(7) colonies per gram. Fungal populations increased over the growing season from 3-6 x 10(5) to 1-4 x 10(6) colonies per gram of soil. Fungi have the potential to decrease soil pH and hence increase the bioavailability of radionuclides such as Cs. In addition, fungi act to facilitate plant nutrition. This could lead to enhanced accumulation of nutrient analogues (e.g. Sr and Ra for Ca; Tc for Mn), but this effect may be masked by improved biomass production. 相似文献
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Hunting is a threat to wildlife within the Hkakaborazi National Park in north Myanmar. We used questionnaire surveys to obtain
data on variables such as commonly targeted species, prices of traded wildlife, reasons for hunting and the relative importance
of livelihood sources. We examine (a) the significance of hunting and trade for livelihoods and explore (b) the impacts of
hunting on targeted species. Ninety per cent of trade records (n = 803) was constituted by seven species commonly targeted by hunters (serow, red goral, muntjac, bear, Assamese macaque,
black musk deer and takin). Commercially valuable species previously targeted by hunters (tiger, otter, pangolin) appear to
be completely absent from current harvest records and potentially in decline. Although farming is the predominant occupation,
hunting (driven by trade) represents a significantly higher source of income than other livelihood activities. Management
recommendations include increased investment in enforcement, education and outreach, small livestock development, improved
crop productivity, demarcation of no-take areas for wildlife and biological monitoring of targeted species. 相似文献
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The Hponkanrazi Wildlife Sanctuary, North Myanmar and three contiguous protected areas, comprise some of the largest expanses
of natural forest remaining in the region. Demand for wildlife products has resulted in unsustainable exploitation of commercially
valuable species resulting in local extirpation of vulnerable species. Camera trap, track and sign, and questionnaire-based
surveys were used to examine (a) wildlife species targeted by hunters, (b) the importance of wild meat for household consumption,
and (c) the significance of hunting as a livelihood activity for resident villages. Certain commercially valuable species
highly preferred by hunters were either completely absent from hunt records (tiger, musk deer and otter) or infrequently obtained
during actual hunts (bear, pangolin). Species obtained by hunters were commonly occurring species such as muntjacs with low
commercial value and not highly preferred by hunters. Fifty eight percent of respondents (n = 84) indicated trade, 27% listed subsistence use and 14% listed human-wildlife conflict as the main reason for hunting (n = 84). Average amount of wild meat consumed per month is not significantly higher during the hunting season compared to the
planting season (paired t-test, P > 0.05). Throughout the year, the average amount of fish consumed per month was higher than livestock or wild meat (Friedman
test, P < 0.0001). Hunting is driven largely by trade and wild meat, while not a critical source of food for a large number of families
could potentially be an important, indirect source of access to food for hunting families. Findings and trends from this study
are potentially useful in helping design effective conservation strategies to address globally prevalent problems of declining
wildlife populations and dependent human communities. The study provides recommendations to reduce illegal hunting and protect
vulnerable species by strengthening park management through enforcement, increasing the opportunity costs of poaching, establishing
no-take zones and research to determine the economic significance of hunting for livelihoods. 相似文献
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A long-term study of the effect of artificial aeration (destratification) of a water storage dam upon the speciation of iron and manganese in the dam waters has been undertaken. Separation of dam samples into soluble and insoluble forms by selective membrane filtration was undertaken before using the techniques of EPR spectroscopy, ion chromatography and gel filtration to assess the speciation of soluble species, and selective extraction and surface analysis (ESCA, SIMS and SEM) techniques to determine the speciation of particulate iron and manganese species. The percentages of soluble iron and manganese before (1983–85) and after (1986–88) artificial aeration are compared for the periods Jan–Dec, Jan–Mar, and Jun–Aug at three depths 6 m, 15 m and 0.5 m above the dam base, to assess the importance of seasonal changes in the various depths of the dam. Although aeration had an initial marked reduction in levels of soluble iron and manganese at all depths of the dam, the concentrations of these mtals showed a steady increase over succeeding years. Analysis of the figures over summer and winter periods shows that the reduction of soluble iron was maintained in summer, but not during winter. Upon aeration, the initial reduction of soluble manganese concentration was maintained in succeeding years in the epilimnic regions of the dam, but not in the hypolimnion. Statistical analysis of data has been undertaken to correlate the changes in relationship between the various forms of iron and manganese with the advent of aeration. 相似文献
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A century ago, tigers were considered pests in Myanmar. Hunters claimed thousands, yet populations persisted. In the past
century, because of habitat loss and prey depletion, coupled with the recent demand for traditional medicines, tiger populations
have been reduced to a few hundred individuals. As a first step toward long-term planning for tigers, and to guide efforts
to increase protected area coverage, the Myanmar government in 1998 initiated a project to develop a revised National Tiger
Action Plan. Extensive surveys confirmed tigers in only 4 of 17 survey locations. Significant populations are thought to persist
in the far North and far South of the country, where large, intact forests offer the potential for tiger recovery. With partnerships
and collaborations, tiger populations can be protected in the short term (<5 years) by expanding protected areas and corridors,
mobilizing enforcement staff to reduce poaching of tigers and prey, and amending existing wildlife legislation in accordance
with international laws. Over the long term (5–20 years), recovery of Myanmar’s tiger populations will depend on increasing
support from local people, zoning tiger areas to reduce habitat loss and disturbance, and maintaining connectivity of existing
national and transboundary forests. This article reviews the development of a new National Tiger Action Plan for the Union
of Myanmar and discusses a blueprint for conservation measures aimed at saving tigers from extinction. 相似文献
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Zaw Aye Cho Cho Gathuka Lincoln W. Takai Atsushi Katsumi Takeshi 《Journal of Material Cycles and Waste Management》2022,24(4):1423-1431
Journal of Material Cycles and Waste Management - Dredged soils are typically mixed with additives to improve their mechanical properties and reduce the risks of leaching toxic elements. An... 相似文献
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