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51.
Josip Kusak Djuro Huber Tomislav Gomerčić Gabriel Schwaderer Goran Gužvica 《European Journal of Wildlife Research》2009,55(1):7-21
The highway from Zagreb to Rijeka stretches 68.5 km through a wildlife core area in Gorski kotar (Croatia). It has 43 viaducts
and tunnels, and one specifically constructed (100 m wide) green bridge (Dedin). One quarter of the total highway length consists
of possible crossing structures. At Dedin green bridge, a total of 12,519 crossings have been recorded during 793 different
days of active infrared monitors being in operation, or 15.8 crossings per day. Two monitored tunnel overpasses had 11.2 and
37.0 crossings per day, respectively, whilst 4.3 crossings occurred per day under one monitored viaduct. Of those crossings,
83.2% were by ungulates and 14.6% by large carnivores. Radio-tracked large carnivores, brown bear (Ursus arctos), grey wolf (Canis lupus) and Eurasian lynx (Lynx lynx), expressed strong positive selection for tunnels and viaducts, whilst avoiding small underpasses or bridges. Selection for
the use of Dedin green bridge was equal to its availability. We conclude that this green bridge, constructed as a measure
to mitigate the negative effects of the studied highway, served its purpose acceptably. Territorial and dispersing radio-tracked
large carnivores crossed the highway 41 times, using both sides of the highway as parts of their home ranges. Overall, the
highway in Gorski kotar does not seem to be a barrier. This demonstrates that it is possible to maintain habitat connectivity
during the process of planning the highway route. 相似文献
52.
Jeff A. Graves Alice Helyar Martin Biuw Mart Jüssi Ivar Jüssi Olle Karlsson 《Conservation Genetics》2009,10(1):59-68
The growing number of grey seals in the Baltic Sea has led to a dramatic increase in interactions between seals and fisheries.
The conflict has become such a problem that hunting was introduced in Finland in 1998 and the Swedish Environment Protection
Agency recommended a cull of grey seals starting in 2001. Culling has been implemented despite the lack of data on population
structure. Low levels of migration between regions would mean that intensive culling in specific geographic areas would have
disproportionate effects on local population structure and genetic diversity. We used eight microsatellite loci and a 489 bp
section of the mtDNA control region to examine the genetic variability and differentiation between three breeding sites in
the Baltic Sea and two in the UK. We found high levels of genetic variability in all sampled Baltic groups for both the microsatellites
and the control region. There were highly significant differences in microsatellite allele frequencies between all three Baltic
breeding sites and between the Baltic sites and the UK sites. However, there were no significant differences in mtDNA control
region haplotypes between the Baltic sites. This genetic substructure of the Baltic grey seal populations should be taken
into consideration when managing the seal population to prevent the hunting regime from having an adverse effect on genetic
diversity by setting hunting quotas separately for the different subpopulations.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
53.
GREGORY J. RETALLACK 《Palaeontology》2011,54(6):1223-1242
Abstract: Red calcareous Middle Cambrian palaeosols from the upper Moodlatana Formation in the eastern Flinders Ranges of South Australia formed in well‐drained subhumid floodplains and include a variety of problematic fossils. The fossils are preserved like trace fossil endichnia but do not appear to be traces of burrows or other animal movement. They are here regarded as remains of sessile organisms, comparable with fungi or plants living in place, and are formally named as palaeobotanical form genera under provisions of the International Code of Botanical Nomenclature. Most common are slender (0.5–2 mm) branching filaments flanked by green‐grey reduction haloes within the red matrix of palaeosol surface horizons (Prasinema gracile gen. et sp. nov.). Other axial structures (Prasinema nodosum and P. adunatum gen. et spp. nov.) are larger and show distinctive surface irregularities (short protuberances and irregular striations, respectively). The size and form of these filaments are most like rhizines of soil‐crust lichens. Other evidence of life on land includes quilted spheroids (Erytholus globosus gen. et sp. nov.) and thallose impressions (Farghera sp. indet.), which may have been slime moulds and lichens, respectively. These distinctive fossils in Cambrian palaeosols represent communities comparable with modern biological soil crusts. 相似文献
54.
Oliveira AC Peres CM Correia Pires JM Silva Pereira C Vitorino S Figueiredo Marques JJ Barreto Crespo MT San Romão MV 《Microbiological research》2003,158(2):117-124
AIMS: The main aims of this work were the study of cork slabs moulds colonization and the evaluation of the moulds diversity during cork processing steps, in different cork stoppers factories. Simultaneously, it was envisaged to perform an evaluation of the air quality. METHODS AND RESULTS: Moulds were isolated and identified from cork slabs and cork samples in four cork stoppers factories. The identification was based on morphological characters and microscopic observation of the reproductive structures. Airborne spore dispersion was assessed using a two stage Andersen sampler. It was observed that Chrysonilia sitophila was always present on cork slabs during the maturing period, but mould diversity appeared to be associated to the different factory configurations and processing steps. CONCLUSIONS: Spatial separation of the different steps of the process, including physical separation of the maturation step, is essential to guarantee high air quality and appropriate cork slabs colonization, i.e. C. sitophila dominance. The sorting and cutting of the edges of cork slabs after boiling and before the maturing step is also recommended. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is very important for the cork stopper industry as it gives clear indications on how to keep high quality manufacturing standards and how to avoid occupational health problems. 相似文献
55.
Field evidence for apparent competition mediated via the shared parasites of two gamebird species 总被引:2,自引:1,他引:1
Although apparent competition mediated via shared parasites is potentially an important force influencing community structure, there is limited evidence to demonstrate its occurrence in the field. Here we show that the intensity of infection by the caecal nematode Heterakis gallinarum picked up by naive grey partridges, both maintained in pens and released on six gamebird estates in the UK, is significantly correlated with the intensity of infection recorded in the previous year from pheasants on those estates. Furthermore, the worm burdens picked up appeared to be sufficient to negatively influence host condition. These results provide evidence that infection from pheasants determines the worm burdens of partridges in the field, supporting the hypothesis that parasite-mediated apparent competition with the pheasant may be a factor influencing the decline and subsequent recovery of wild grey partridges. 相似文献
56.
基于PSR模型的凌河口湿地生态系统健康评价与预警研究 总被引:4,自引:0,他引:4
凌河口湿地自然保护区是辽河流域主要的湿地保护区域。选取1995年、2000年、2005年、2009年和2014年TM影像作为研究的数据源,在3S技术平台支撑下构建了凌河口湿地空间信息数据库,获取了5个时期的景观格局指数。运用PSR数学模型,从压力、状态、响应3个方面选取10个评价指数,构建了凌河口湿地生态系统健康评价指标体系;采用AHP方法确定各项指标权重指数,应用逻辑斯蒂增长模型(Logistic growth model)对各个单项指标进行单因子评价,最后用计算CEI的综合评价法对5个时期湿地的生态健康情况进行综合评价。结果表明:1995年、2000年生态系统健康指数为0.642、0.617,凌河口湿地生态系统状态为比较健康;2005年、2009年和2014年生态健康指数为0.524、0.436和0.405,凌河口湿地生态系统处于亚健康的状态,应及时采取措施对该研究区进行生态系统保护。最后通过选取基于灰色系统理论的预测模型,构建凌河口湿地生态健康预测模型GM(1,1),对模型进行精度检验,发现灰色绝对关联度、后验差比值和小误差概率的精度检验等级均为一级,预测模型精度较为理想,因此采用GM(1,1)模型对凌河口湿地进行生态系统健康预测研究。预测结果表明:未来20年的湿地生态健康值分别为:0.357、0.321、0.291、0.267,研究区处于一般病态,并有向病态发展的趋势,生态健康面临愈来愈严重的威胁,对湿地进行保护和管理刻不容缓。 相似文献
57.
58.
Role of lipopeptides produced by Bacillus subtilis GA1 in the reduction of grey mould disease caused by Botrytis cinerea on apple 总被引:5,自引:0,他引:5
AIM: Test of Bacillus subtilis strain GA1 for its potential to control grey mould disease of apple caused by Botrytis cinerea. METHODS AND RESULTS: GA1 was first tested for its ability to antagonize in vitro the growth of a wide variety of plant pathogenic fungi responsible for diseases of economical importance. The potential of strain GA1 to reduce post-harvest infection caused by B. cinerea was tested on apples by treating artificially wounded fruits with endospore suspensions. Strain GA1 was very effective at reducing disease incidence during the first 5 days following pathogen inoculation and a 80% protection level was maintained over the next 10 days. Treatment of fruits with an extract of GA1 culture supernatant also exerted a strong preventive effect on the development of grey mould. Further analysis of this extract revealed that strain GA1 produces a wide variety of antifungal lipopeptide isomers from the iturin, fengycin and surfactin families. A strong evidence for the involvement of such compounds in disease reduction arose from the recovery of fengycins from protected fruit sites colonized by bacterial cells. CONCLUSIONS: The results presented here demonstrate that, despite unfavourable pH, B. subtilis endospores inoculated on apple pulp can readily germinate allowing significant cell populations to establish and efficient in vivo synthesis of lipopeptides which could be related to grey mould reduction. SIGNIFICANCE AND IMPACT OF THE STUDY: This work enables for the first time to correlate the strong protective effect of a particular B. subtilis strain against grey mould with in situ production of fengycins in infected sites of apple fruits. 相似文献
59.
A. E. Kalamarakis N. Petsikos-Panagiotarou B. Mavroidis B. N. Ziogas 《Journal of Phytopathology》2000,148(7-8):449-455
Fluazinam is a new active ingredient for the control of grey mould, belonging to the novel broad spectum phenylpyridinamine fungicides. The effect of fluazinam was studied on one wild type and four strains of Botrytis cinerea , which had been isolated from vegetable crops in Greece, and were resistant to benzimidazoles and/or dicarboximides and to the mixture of benzimidazoles (carbendazim) + phenylcarbamates (diethofencarb). In vitro fluazinam was found to be highly active against strains of B. cinerea which were sensitive or resistant to benzimidazoles or exhibited multiple resistance to benzimidazoles, dicarboximides and to the mixture carbendazim + diethofencarb [EC50 and EC95 values (concentration of active ingredient that suppresses mycelial growth to 50 and 95%, respectively, of that of the fungus on fungicide-free agar medium) calculated with probit analysis, ranged from 0.044 to 0.069 and 0.58 to 1.6 μg/ml, respectively]. No cross-resistance was observed between fluazinam and the market products benomyl, iprodione or carbendazim + diethofencarb. Preventive applications of fluazinam in vivo completely inhibited infections of cucumber seedlings by all the above-mentioned resistant strains of B. cinerea . Benomyl and iprodione did not effectively control the benzimidazole- and dicarboximide-resistant strains. The mixture of carbendazim + diethofencarb insufficiently controlled the strain of B. cinerea with moderate resistance to benzimidazoles. The results of this investigation indicate that it should be possible to use fluazinam as an alternative in resistance management programmes against grey mould. 相似文献
60.
人类活动影响下科尔沁沙地沙漠化动态的敏感性分析及灰色预测 总被引:19,自引:2,他引:19
利用90年代1◊25万和1◊50万的TM遥感影像及GIS获得的数据,结合该区70、80年代遥感调查数据,分析了科尔沁地区6个县的土地覆盖类型和潜在沙漠化动态及敏感因子。结果表明,1980~1990年该区的沙化面积从53%扩大到70%,林地下降10.7%,草地增加8.38%,主要为低覆盖草地。由于10年来人口密度增加了10人·km-2,耕地平均增加了7%,人口增加和活动是土地覆盖变化的敏感性因子。分析该区沙漠化的自然因素表明气候变化导致沙漠化的正逆过程,人类活动是近代该区沙漠化加剧的直接原因。灰色预测表明该地区2000年以后人口增加,而沙漠化呈增加和减少两种趋势. 相似文献