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Estimating tropical biomass is critical for establishment of conservation inventories and landscape monitoring. However, monitoring biomass in a complex and dynamic environment using traditional methods is challenging. Recently, biomass estimates based on remotely sensed data and ecological variables have shown great potential. The present study explored the utility of remotely sensed data and topo-edaphic factors to improve biomass estimation in the Eastern Arc Mountains of Tanzania. Twenty-nine vegetation indices were calculated from RapidEye data, while topo-edaphic factors were taken from field measurements. Results showed that using topo-edaphic variables or vegetation indices, biomass could be predicted with an R2 of 0.4. A combination of topo-edaphic variables and vegetation indices improved the prediction accuracy to an R2 of 0.6. Results further showed a decrease in biomass estimates from 1162 ton ha?1 in 1980 to 285.38 ton ha?1 in 2012. This study demonstrates the value of combining remotely sensed data with topo-edaphic variables in biomass estimation. 相似文献
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GeoJournal - Renewable energy is key to the development of Ghana’s power sector especially for the replacement of fossil fuels, which have become much a talk globally for contributing to... 相似文献
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Natural Hazards - This article constitutes an effort towards providing an academic overview and grounding for the concept of capacities in the context of disaster studies and disaster risk... 相似文献
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Wen-Kui Dai Grace Mercy Amboka Edwin Luguba Kadiori Qing-Feng Wang Chun-Feng Yang 《山地科学学报》2017,14(10):1995-2002
Phenotypic plasticity and/or pollinator-mediated selection may be responsible for the changes in floral traits of plants when they are forced to live in new conditions. Although the two events could be independent, we hypothesized that phenotypic plasticity in floral traits might help to coordinate plant-pollinator interactions and enhance plant reproductive success in changing habitats. To test this hypothesis, we investigated floral traits and pollination on three natural populations of a lousewort (Pedicularis siphonantha) ranging at different elevations, as well as two downward transplanted populations in Shangeri-La County and Deqin County, northwest Yunnan, China. The results indicated that floral traits, i.e. phenology, longevity, display size, corolla tube length and pollen production differed significantly among populations. Moreover, or the two transplanted populations, floral traits diverged from their original populations, but converged to their host populations. Although the phenotypic plasticity in floral traits might be a rapid response to abiotic factor such as warmer environment, the changes in floral traits were found to be well adapted to pollination environment of the host population. Compared with plants of their original habitats in higher elevation, the transplanted individuals advanced flowering time, shortened flower longevity, reduced floral display size and pollen production, received higher visiting frequency and yielded more seeds. These findings suggested that phenotypic plasticity of floral traits might help plants adjust their resource allocation strategy between preand post-pollination stages in response to harsh or temperate conditions, which might correspondingly meet a pollinator-poor or hyphen rich environment. This would be beneficial for the widely-distributed species to adapt to various environmental changes. 相似文献
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Asante-Okyere Solomon Shen Chuanbo Ziggah Yao Yevenyo Rulegeya Mercy Moses Zhu Xiangfeng 《Natural Resources Research》2020,29(4):2257-2273
Natural Resources Research - The significant body of research on lithology identification in recent years has laid emphasis on the improvement of classification performance using hybrid machine... 相似文献
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Conflicts undermine forest-based livelihoods for the rural poor. Conflict management is key to preventing such conflicts. This article analyzes actor perceptions of forest- and tree-related conflicts and conflict management in Ghana's high forest zone. It also assesses a phased methodology that promotes shared problem definition and ownership of recommendations on conflict resolution strategies through the presentation and discussion of findings from document analysis, surveys, interviews, and focus-group discussions at a workshop with forest professionals held in Kumasi, Ghana. The study found that conflicts are inherent in forest-based livelihoods due to policy and legislative failures and institutional deficiencies, perceived goal incompatibility, opportunities for interfering with the attainment of one another's goals, and environmental scarcity. Ongoing forest governance reforms in Ghana should consider the stepwise conflict management model developed by the workshop participants involved in this study, but expand it to include the views of other stakeholder groups. 相似文献
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Beppu R Nojima K Tsuruda S Gomez-Delan G Barte-Quilantang M Taniyama S Sagara T Nishio S Takayama H Miyazawa K Asakawa M 《Marine pollution bulletin》2008,56(4):758-763
During surveillance of the distribution of the paralytic shellfish poison (PSP)-producing dinoflagellate in 2003, 2004 and 2005 along the coastlines of the Seto Inland Sea, Hiroshima Prefecture, Japan, some species of toxic phytoplankton were isolated from the eastern coasts, Bingo-Nada, the central regions of the Seto Inland Sea. It was rather unexpectedly revealed from the basis of the morphological characteristics that they were unambiguously identified as Alexandrium tamiyavanichii and Alexandrium catenella. Two strains (ATY041106, ATY051018) of A. tamiyavanichii showed a specific toxicity of 38.7 x 10(-6) and 111.5 x 10(-6)MU/cell, respectively. These values seemed to be several times or much higher than that of A. catenella (AC030816, AC040614), having a specific toxicity of 4.5 x 10(-6) and 4.1 x 10(-6)MU/cell, respectively, isolated in the same area. From the results of HPLC-furuorometric analysis, it revealed that the toxins in ATY041106 exist almost exclusively as beta-epimers (C2, GTX3, GTX4), which accounted for 72.7 mol%. The toxin profiles of this strain are featured by the presence of a large amount of GTX3 (59.1 mol%) and a small amount (20.6%) of C1 and 2 in comparison with the PSP compositions of A. tamarense, which is isolated as the main responsible species in Hiroshima Bay, a western part of coastal sea in Hiroshima Prefecture. On the other hand, it revealed that the toxin profiles of two strains (AC030816, AC040614) of A. catenella exist almost exclusively as beta-epimers (C2, GTX3, GTX4), which accounted for 81.8 and 56.5 mol%, as the same manner. The toxin profiles of these two strains are featured by the presence of a large amount of C2 (80.5 and 46.3 mol%) in comparison with the PSP compositions of A. tamiyavanichii. To our knowledge, this is the first record to show the distribution and harmful influence of A. tamiyavanichii and A. catenella in Bingo-Nada in Hiroshima Prefecture. Though contamination of bivalves with these PSP-producing planktons in this area has not occurred yet so far, attention should be paid to this species as well as the other causative dinoflagellate from the stand point of public health and food hygiene. 相似文献
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Engaging communities in managing multiple hazards: Reflections from small islands in North Sulawesi,Indonesia 
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下载免费PDF全文 Mercy M.F. Rampengan Lisa Law J.C. Gaillard Agni Klintuni Boedhihartono Jeffrey Sayer 《Singapore journal of tropical geography》2016,37(2):249-267
Participatory methods are a common approach for giving voice to local communities in hazard and disaster research. Drawing on a study that trialled and modified a range of participatory methods in North Sulawesi, eastern Indonesia, this paper reflects on how such methods help document the capacities of small island communities. We assessed capacity from a sustainable livelihoods perspective, identifying the assets that enable villagers to cope with hazards. This overall approach promoted a discourse of strengths and resourcefulness, contrasting with vulnerability and needs‐assessment approaches common to government and non‐governmental organizations, which tend to focus on weaknesses and can sometimes fuel undeliverable expectations of funding. We provide a critical reflection on participatory methods and their significance for researchers, policy makers and funding agencies working with communities in hazard‐prone regions. 相似文献
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