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931.
Robert Šakić Trogrlić Grant B. Wright Adebayo J. Adeloye Melanie J. Duncan Faidess Mwale 《Environmental Hazards》2018,17(2):107-127
Current flood risk strategies in Malawi are characterized by community-based flood risk management (CB-FRM), even though studies explicitly documenting evidence of successful CB-FRM remain limited. This paper investigates the realities and challenges of CB-FRM as seen through a lens of different stakeholders. In order to capture the experiences of CB-FRM, a predominantly qualitative research framework was developed. In 2016, 11 focus group discussions with stakeholder groups (local communities, local government and non-governmental organisations) were held. Additionally, informal discussions, field visits, a short survey and an extensive desk study were undertaken. The findings were analysed according to the major themes that emerged related to the realities and challenges of specific stakeholder groups. Although response and relief still remain prominent components of CB-FRM in Malawi, a number of mitigation and preparedness activities is observed. However, a lack of in-country resources, relief-oriented aid approaches and an ‘aid dependency’ syndrome represent obstacles. Different stakeholder groups share similar challenges in terms of financing, participation, decentralised governance and project management. Lack of project sustainability and localised ownership also emerged as major challenges. The identified challenges shed light on the frontiers and directions in which improvements are needed, thus offering a valuable contribution to the existing knowledgebase. 相似文献
932.
传统山区灾害滑坡风险预测方法,对山区滑坡风险进行预测与分析同时,存在预测响应滞后以及预测准确率较低问题。提出山区灾害滑坡风险非线性预测研究方法。基于山区灾害滑坡影响因素,构建非线性斜坡系统,对斜坡单元进行量化分析,完成滑坡非线性动力学模型设计。利用该动力学模型与时间序列的研究,对滑坡形态与时间影响进行综合分析,判定危险滑坡源,对其进行空间相分析,完成山区灾害滑坡风险非线性预测。实验数据表明所提非线性预测方法相比于传统预测方法,响应时间提升96.18%,准确率提升48.95%。 相似文献
933.
采用三重嵌套网格,利用NCEP的1°×1°再分析资料以及新一代中尺度预报模式WRF模式,对2014年6月6日08:00-7日08:00川滇切变线致灾暴雨过程进行了数值模拟实验,并对结果进行诊断分析。结果表明:WRF模式可以较为客观地模拟出暴雨过程的落区和强度,较好地反映了强降水过程的实况和基本特征,模式能很好地指示出强降水发生的高湿水汽条件以及正涡度发展、强烈上升运动和下正上负垂直螺旋度结构的动力条件,模拟的上升运动位置及700 hPa正涡度带和正垂直螺旋带亦对强降水落区有很好的指示性,另外除了模拟的切变线位置稍偏西偏南而导致暴雨区稍偏西偏南外,对高低层影响系统的走向、结构、位置和强度的模拟结果与实际结果相近,表明该模式对云南省切变线致灾暴雨系统具有较好的模拟效果。 相似文献
934.
Alejandro Valladares Germán Manríquez Benjamín A. Suárez-Isla 《Marine Biology》2010,157(12):2731-2738
The pattern of shell shape variation in populations of the mussel, Mytilus chilensis (Hupe 1854) from Southern Chile was analyzed as a function of sample origin (cultivated vs. wild) and latitude, using standard
tools of geometric morphometrics for landmark data. Additionally, posterior adductor muscle index (PAMI), Freeman condition
index and shell thickness were measured in each sample. Highly significant differences in shell shape components were found
among mussel populations. These differences are related to the origin of samples (expansion of the posterior adductor muscle
scar, elongation of the lateral ligament and of the ventral umbo position in non-cultivated samples) and to latitude (more
elongated shells and more extended posterior adductor muscle scar in most southern samples when compared with the northernmost
ones). PAMI and shell thickness were statistically higher in wild population, and Freeman condition index was higher in cultivated
shells. It is suggested that in wild populations of M. chilensis, the mussels may face higher predator pressures and other environmental stress factors. Consequently, individuals may be using
higher energy fraction to reinforce shells and to promote adductor muscle growth at the expense of somatic growth. In contrast,
individuals found in calm aquaculture environments are relatively protected from predators and use most of their assimilated
energy in somatic growth. In turn, this growth depends on changes that covariate with shell morphology. 相似文献
935.
Sea lions are generally considered opportunistic feeders. However, studies from different areas suggest their diet consists
mostly of four to five types of prey. Previous studies in Galapagos sea lions have identified at least three feeding strategies
for this species, suggesting diversification of their diet. Diet diversification is favored in organisms with relatively high
trophic position and subject to high intra-specific and low inter-specific competition. Zalophus wollebaeki meet these criteria as the only pinniped on San Cristobal Island, where three sea lion rookeries are located within 11 km:
a distance considerably shorter than their 41 km foraging range. To measure the degree of diet diversification, we used scats
and stable isotope analyses. A total of 270 scat samples from lactating females and 142 fur samples from sea lion pups were
collected during the breeding season 2006. The scat analysis identified distinct diets among rookeries, with minimal trophic
overlap (Cλ = 0.19), a trophic level TL = 4.5 (secondary–tertiary carnivore), and trophic breadth of a specialist predator (B
i
= 0.37). The mean δ15N and δ13C values were 13.07 ± 0.52 and −16.34 ± 0.37, respectively. No significant difference was found in the δ15N values from the sea lion rookeries, but differences were found inter- and intra-population in δ13C values for pups from different groups (ANOVA P < 0.05). Our results indicate that diet diversification is present in the Galapagos sea lion and may play important role
to the survival of the species in a habitat where pinniped populations are limited. 相似文献
936.
Iñaki Rodríguez-Prieto José Martín Esteban Fernández-Juricic 《Behavioral ecology and sociobiology》2010,64(12):1937-1945
Habituation to nonlethal predation stimuli may provide benefits for animals living in areas with frequent encounters with
low-risk predators. On the other hand, individuals can be very consistent in their antipredator responses, with shy individuals
showing greater degree of responsiveness than bold individuals. However, the link between habituation or boldness and individual
benefits has not been thoroughly investigated. We established whether and how two behavioral components associated with antipredator
responses (habituation and boldness, and their interaction) would influence body condition, which is a parameter related to
fitness. We conducted an outdoor semi-natural experiment with Iberian wall lizards (Podarcis hispanica). Individual boldness was consistent across contexts, but we did not find any effect of boldness or the interaction between
boldness and habituation on body condition. However, those individuals that habituated more readily to a frequent predatory
stimulus were able to increase their body condition more relative to lizards that habituated less. This finding highlights
the importance of individual differences in behavioral plasticity, which could influence traits related to fitness. Habituation
can provide benefits for individuals exposed to low-risk predators; however, individuals more prone to habituation could also
experience mortality costs by wrongly habituating to a dangerous predator. 相似文献
937.
938.
Distribution and availability of potentially toxic metals in soil in central area of Belgrade,Serbia 总被引:1,自引:0,他引:1
Rabia Ahmed Ghariani Ivan Gržetić Mališa Antić Snežana Nikolić Mandić 《Environmental Chemistry Letters》2010,8(3):261-269
Belgrade, capital city of Serbia, has over 1,600,000 inhabitants and over 400,000 vehicles trafficking every day on its streets.
The investigation of soil pollution was performed by sequential extraction analysis to investigate the availability of potentially
toxic metals (Zn, Cd, Pb, Co, Ni, Cu, Cr and Mn) under different oxidation and pH conditions. All investigated metals were
mainly extracted from soils with neutral or acidic extractants. Serious pollution was observed along roads and streets with
high traffic frequency, but Pb and Ni pollution was the highest since their concentrations exceed both soil Serbian standard
and Canadian guidance values and is characteristic for all investigated sites. Cd, Cu, Cr and Zn concentrations are moderately
high since they are between Canadian guideline and Serbian standard. 相似文献
939.
Alžbeta Jarošová Jiří Harazim Lenka Krátká Doubravka Kolenčíková 《Environmental Chemistry Letters》2010,8(4):387-391
Phthalates are animal carcinogens and may cause death or tissue deformities. Samples of feedstuffs collected in 2005 and 2006
from industrial feed manufacturers in the Czech Republic were analysed for contamination with phthalic acid esters (PAEs),
specifically di-2-ethylhexyl phthalate (DEHP) and di-n-butyl phthalate (DBP). Samples of feed additives, premixes and raw materials were collected (year 2005, n = 26). For soybean oil, the total volume of phthalates measured (DBP + DEHP) reached a level of 131.42 mg kg−1; for rapeseed oil, fish meal and animal fats, the levels measured were 15.00, 7.96 and 58.87 mg kg−1, respectively. The lowest level of DBP + DEHP was found in corn (2.03 mg kg−1). Since phthalates were detected, samples of feed additives (n = 28) and raw materials (n = 28) were collected again in 2006. The highest levels of DBP + DEHP were found in raw materials containing fat. Phthalate
levels in rapeseed oil samples ranged from 1.38 to 32.40 mg kg−1 DBP + DEHP. For feed additives, contamination levels in vitamins and amino acids ranged from 0.06 to 3.15 and 1.76 to 4.52 mg kg−1 DBP + DEHP, respectively. Here, we show that the levels of PAEs found in cereals such as wheat, barley and corn may be regarded
as being alarmingly high, because cereals make up the largest proportion of compound feed of farm animals. 相似文献
940.
Kormaňáková Marcela Remešová Marcela Vančová Terézia 《Journal of Material Cycles and Waste Management》2021,23(4):1348-1364
Journal of Material Cycles and Waste Management - The problem of food waste is broadly discussed, but empirical data are still missing. The importance of this topic increases as the reporting of... 相似文献