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41.
- 1. An internationally important population of the freshwater pearl mussel (Margaritifera margaritifera) was rediscovered in a small river in north‐west Russia.
- 2. A survey of visible mussels in 2008/2009 indicated an estimated population of 40 000 individuals. This is the largest population currently known in the Leningrad oblast and is comparable with the entire pearl mussel population of some western European countries.
- 3. The average density of visible mussels was 29.6 individuals m?2 in the middle part of the river. In the four largest mussel beds maximum densities of 1000+ individuals m?2 were recorded. Such densities are exceptional and have not been reported elsewhere in Europe during the last 100 years.
- 4. Live juvenile mussels were recorded, indicating that that this population is viable, although further investigation is required to establish its status.
- 5. Analysis of the population age structure, based on the measurement of empty shells, showed an age class distribution similar to those reported for other healthy Margaritifera populations.
- 6. Only two live juveniles were found. However, this is likely to be due to the survey being restricted to counts of visible mussels only, and the age structure being based on the analysis of dead shells.
- 7. The population's current status and possible reasons for its survival in this river are discussed. Conservation measures should include the construction of a fish ladder to make fish migration through the culvert possible, removal of a metal screen preventing fish migration from the upper reaches of the river to the lake, reduction of recreation activities, and providing the local children's camp with water treatment facilities. Copyright © 2011 John Wiley & Sons, Ltd.
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俄罗斯8号大樱桃是从辽宁省大连市引入合肥市肥西县的新品种,通过观察该品种在合肥地区的果实经济性状、物候期和适应性等性状,研究肥水管理、整形修剪和病虫害防治等管理措施,探索出江淮丘陵地区引进欧洲大樱桃的种植技术。结果表明俄罗斯8号大樱桃为中庸丰产型大樱桃树种,平均单果重12.9g,可溶性固形物含量为18.9%,总糖含量为15.6%,可食率较高,在合肥地区5月上旬开始成熟,成熟期较早,货架期长,在合肥市肥西县采用避雨连栋棚室栽培综合性状表现良好。 相似文献
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本文概述俄罗斯东南部马铃薯甲虫发生现状,分析黑龙江省的地理和季风特点,评估马铃薯甲虫入侵对国家主粮安全风险和黑龙江省马铃薯甲虫监测防控形势,提出相应对策建议。 相似文献
45.
俄罗斯保护竞争法对行政垄断有专门定义,调整行政垄断主体范围广泛,有行政机关、立法机关等,行为种类有单个行政机关、行政机关之间及行政机关与经营者之间的行为,有作为也有不作为。俄罗斯反垄断署有立法、司法及行政执法权,能调查、审理并处罚行政垄断案件,且为行政垄断设置了民事、行政、刑事法律责任制度,规制行政垄断执法效率高、成本低。我国应重新界定行政垄断及其表现形式,调整行政垄断主体范围,完善行政主体法律责任,建立独立权威的执法机构,以实现《反垄断法》对行政垄断的有效规制。 相似文献
46.
Remote sensing observations over areas of the former Soviet Union suggest that there may be important ongoing influences on forested landscapes resulting from divergent land use and forest management associated with the Soviet versus post-Soviet eras. As the Russian Federation implements its new Forest Code and associated regulations, knowledge of existing forest patterns and trends, plus the development of methods with which to understand the landscape-level influence of different forest management strategies is increasingly important. We developed spatial–temporal models and projections of forest patterns and trends over Soviet and early post-Soviet forest management eras for a study site in the Lake Baikal region in southern Siberia. We used Landsat-derived land-cover data, logistic regressions, and Markov and cellular automata methods (CA–Markov) to characterize patterns and trends 1975–1989 and 1990–2001, and to develop predictive scenarios through 2013. Relationships of forest types (Conifer, Mixed, Deciduous) and Agriculture to other explanatory environmental variables indicated mostly consistent forest–environment relationships, but some different spatial relationships between eras were found for Cut and Regeneration disturbance types. Landscape proportional trends showed greater differences between eras. Cut proportions observed via Landsat in 2001 were approximately 74% lower, and the area of Conifer observed was approximately 14% higher, than modeled proportions predicted for 2001 using 1975–1989 Soviet era transition rates. The proportion of Cut projected for 2013 was about 80% lower when based on early post-Soviet era probabilities. Overall, modeled results indicate that should early post-Soviet trends continue, low rates of logging, some agricultural abandonment, re-growing forests especially near access routes, increases in deciduous cover, along with continued or increased fire events in mixed and conifer forests will define the landscape. Should forest management change, for example to Soviet era rates and patterns of harvest, different outcomes are projected. More broadly, results highlight the real and prospective effects that divergent management strategies can have on forested landscapes, and demonstrate that land-cover data combined with emerging spatial–temporal modeling methods provide an approach to understand and project the complex and ongoing influences associated with changing forest management at landscape scales. 相似文献
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对俄罗斯森林资源开发前景、开发潜力、资源结构以及利用价值作了深入的探索研究。通过在俄罗斯远东林区进行森林资源的合理开发利用,缓解国内市场对木材的供需矛盾,并带动了对俄的资源开发和经贸事业的发展。 相似文献
49.
微生物农药在俄罗斯的应用进展 总被引：1，自引：0，他引：1
微生物农药因其副作用小、对环境兼容性好而日益成为全球农药发展的一种趋势和方向。本文以细菌杀虫剂、真菌杀虫剂、病毒杀虫剂、微生物除草剂、植物生长调节剂、农用抗生素作为微生物农药的代表,介绍了微生物农药的研究、应用现状及其在俄罗斯的研究进展,并对我国与俄罗斯在微生物农药领域的合作进行了展望。 相似文献
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