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Seamus D. Maclennan Rosemary J. Groom David W. Macdonald Laurence G. Frank 《Biological conservation》2009,142(11):2419-2427
Lions (Panthera leo) are in decline throughout most of their range due to human persecution, largely provoked by depredation on livestock, and there is debate as to the usefulness of financial instruments to mitigate this conflict. Intending to reduce local lion-killing, the Mbirikani Predator Compensation Fund compensates members of Mbirikani Group Ranch for livestock depredation at a flat rate (close to average market value), after the kill has been verified and with penalties imposed for poor husbandry. Despite penalizing claimants, 55% of claims arose because livestock were lost in the bush. Between 1st April 2003 and 31st December 2006, 754 cattle, 80 donkeys and 1844 sheep/goats were killed (2.31% of the total livestock herd each year). Forty-three percent of kills were ascribed to spotted hyaenas (Crocuta crocuta); leopards (Panthera pardus) and cheetahs (Acinonyx jubatus) were blamed for 37% of cases, lions 7%, jackals (Canis mesomelas) 7% and buffalo (Syncerus caffer) and elephants (Loxodonta africana) together 6%. Significantly more attacks took place during months of lower rainfall but the rate of attacks was not related to the density of livestock on the ranch, or the ratio of wild herbivores to domestic stock. There was no correlation between local market prices and the number of claims per month. Despite compensation, at least one lion per year was killed in 2004, 2005 and 2006. We describe some features of large carnivore depredation in the study area and suggest that regional recovery of the lion population may require compensation on a wider scale. 相似文献
24.
Leela Hazzah Monique Borgerhoff Mulder Laurence Frank 《Biological conservation》2009,142(11):2428-2437
African lion (Panthera leo) populations are in decline throughout most of Africa, but the problem is particularly acute in southern Kenya, where Maasai people are spearing and poisoning lions at a rate that will ensure near term local extinction. Lion killing is shaped by Maasai perception of livestock depredation, socio-economic factors, and the complex relationship between Maasai and conservation. These all affect tolerance for lions and consequently Maasai behavior towards conservation initiatives and carnivores in general. We used an in-depth quantitative questionnaire and participatory rural appraisals (PRAs) to identify the social and ecological predictors of lion killing and to investigate the effect of a compensation scheme on individual tolerance. Individuals who lose a greater proportion of their livestock to predators relative to their overall livestock loss, those affiliated with an evangelical church, and those who mainly sell rather than accumulate livestock all reported a higher propensity to kill carnivores. The future of carnivore conservation in this region depends on a better understanding of the nuances of human–carnivore conflict and a concerted effort to address appropriate cultural and community-level institutions, chiefly by providing economic benefits to local people who engage in positive conservation activities. 相似文献
25.
Laurence Haller Essoêfli Amedegnato John Poté Walter Wildi 《Water, air, and soil pollution》2009,203(1-4):217-227
Extended persistence of enteric bacteria in coastal sediments and potential remobilization of pathogens during natural turbulence or human activities may induce an increased risk of human infections. In this study, the effect of sediment characteristics such as particle grain size and nutrient and organic matter contents on the survival of fecal indicator bacteria (FIB) including total coliforms, Escherichia coli, and Enterococcus was investigated. The experimentation was carried out for 50 days in microcosms containing lake water and different contaminated freshwater sediments in continuous-flow and batch conditions. Results of this study revealed: (1) extended FIB survival in sediments up to 50 days, (2) higher growth and lower decay rates of FIB in sediments with high levels of organic matter and nutrients and small (mainly silt) grain size, and (3) longer survival of Enterococcus sp. compared to E. coli and total coliforms. FIB survival in sediments and possible resuspension are of considerable significance for the understanding of permanent microbial pollution in water column and therefore human risk during recreational activities. 相似文献
26.
Hypnotically created memory among highly hypnotizable subjects 总被引:2,自引:0,他引:2
A pseudomemory of having been awakened by some loud noises during a night of the previous week was suggested to 27 highly hypnotizable subjects during hypnosis. Posthypnotically, 13 of them stated that the suggested event had actually occurred. This finding has implications for the investigative use of hypnosis in a legal context. 相似文献
27.
Summary Flowering plants of Rosa hybrida L. cv Meirutral have been obtained either from direct regeneration of adventitious shoots on leaf and root fragments, or through organogenesis and somatic embryogenesis on calli derived from anther, ovule, petal, sepal, receptacle, leaf, stem internode, root and zygotic embryo tissues. The calli derived from floral parts exhibited rhizogenesis. In this case direct induction of adventitious shoots from selected roots had to be performed in order to generate plants. A histological study of the morphogenetic calli was carried out. The plants regenerated directly and those regenerated from calli of leaf, stem internode, root and zygotic embryo tissues, together with reference plants propagated by cuttings, were compared on a phenotypic basis by taking into account petal number, form and colour, and plant growth habit. From these observations, it can be concluded that directly regenerated plants are as stable as reference plants while plants regenerated from callus are unstable, especially those derived from zygotic embryo tissues.Abbreviations BAP
6-benzylaminopurine
- 2,4-D
2,4-Dichlorophenoxyacetic acid
- GA3
gibberellic acid
- IAA
3-indole-acetic acid
- MS
Murashige and Skoog
- NAA
1-naphthalene acetic acid 相似文献
28.
Ellen B Wiedner Ramiro Isaza Laurence E Galle Kathleen Barrie William A Lindsay 《Journal of zoo and wildlife medicine》2006,37(3):397-400
A 47-yr-old female Asian elephant (Elephas maximus) developed a corneal stromal abscess in her right eye. The elephant was trained to open her eye for topical ophthalmic therapy, and was treated six times daily with antibiotics and an antifungal solution for almost 2 mo. Nonsteroidal anti-inflammatory drugs were used to control pain, and atropine was applied topically to dilate the pupil and provide additional comfort. Vascularization of the abscess began shortly after initiating therapy, and complete resolution was obtained by 7 wk. 相似文献
29.
Mrklas Ole Chu Angus Lunn Stuart Bentley Laurence R. 《Water, air, and soil pollution》2004,159(1):249-263
The release of alkanolamines and glycols into the subsurface soils poses a potential hazard to the environment through impacted soil and groundwater. This study investigated aerobic and anaerobic biodegradability of monoethanolamine (MEA), ethylene glycol (MEG) and triethylene glycol (TEG). Significant levels of MEA (31 000 mg/kg), MEG (500 mg/kg) and TEG (2100 mg/kg) were successfully aerobically biodegraded in bioreactors. The aerobic slurry experiments suggested initial phosphate (P) limitation, as biodegradation rates increased by one order of magnitude after phosphate addition. Anaerobic decay of MEA, MEG and TEG was unaffected by P-addition. MEA, MEG and TEG degradation products such as acetate, ethanol and ammonium at about 75 000 mg/kg, 8100 mg/kg and 8800 mg/kg degraded completely and did not prevent aerobic biodegradation. This study confirms proposed biodegradation pathways of MEA, MEG, TEG and their breakdown products in natural soil and groundwater using indigenous microbes. Levels of contamination studied here are significantly higher than previously reported. 相似文献
30.
Philipp Franken Natalia Requena Britta Bütehorn Franziska Krajinski Gerrit Kuhn Laurence Lapopin 《Archives of Agronomy and Soil Science》2013,59(4):271-286
The molecular analysis of the arbuscular mycorrhizal (AM) symbiosis started at the beginning of this decade. The paper summarises the work of the ‘Laboratorium für Molekulare Genetik arbuskulärer Mykorrhiza’ at the MPI für terrestrische Mikrobiologie in Marburg on three major topics. Firstly, the plant response to the mycorrhizal colonisation was analysed using both, targeted and non‐targeted approaches. As an example, the localisation of the gst1 mRNA in potato mycorrhiza is shown. Second, molecular techniques were established to analyse gene expression of the fungal partner of the symbiosis. We present a differential RNA display analysis of spore germination in two AM fungi and the cloning of a gene from Glomus mosseae that shows expression at all stages of the fungal life cycle. In the last part, we introduce the work we are carrying out with a new root endophytic fungus, Piriformospora indica. Infection experiments on maize showed that despite the fungus performs as a root necrotroph, it has a positive effect on plant growth. 相似文献