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21.
孙殿芝 《内蒙古林业调查设计》2007,30(2):15-16
文章在分析牙克石市自然条件及水土流失特点的基础上,提出牙克石市水土保持生态修复的可行性及生态修复的措施,以及近年来牙克石市生态修复所取得的可喜成果。 相似文献
22.
近年来,河南省省委省政府非常重视食品安全工作。但是,由于河南的区域性和食品安全本身的复杂性,在现实中仍然存在着诸多问题,主要从商家自身、消费者、监管部门和媒体等方面分析食品安全问题,并提出从建立完善食品安全追溯体系、加强科普知识宣传、加快培养具有道德约束的专业性科学传播人才、完善食品安全法律法规体系建设、构建食品安全诚信体系等5个方面着手,为加快推进河南食品安全大省建设提供支撑条件。 相似文献
23.
DONOSO Leonito Acosta 《中国林业科技(英文版)》2005,(1)
The Luntiang Kamaynilaan Project (Metro ManilaGreening Project) launched in 1988 planted trees inmajor thoroughfares, center islands, school premisesand other idle public lands, was basically a governmenteffort. When the funds ran out, the project also fizzledout. In both projects however, it is evident that the keyfactor is peoples participation.Gaining lessons from the past two projects, thegovernment established a collaborative effort ofgovernment and non-government organizations. TheCl… 相似文献
24.
从地理位置、水质及沉积物、红树林、珊瑚礁海岸等方面介绍亚龙湾生态自然环境特点,分析其生态旅游发展现状、形式及成效,提出对亚龙湾生态环境保护的建议。 相似文献
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- The once plentiful population of the tufted ghost crab, Ocypode cursor, a legally protected species, suffered a steep decline along the densely populated Mediterranean coast of Israel.
- Here we assessed the effects of recreational disturbance on crab populations in three sandy shore nature reserves and adjacent bathing beaches with differing accessibility during the summers of 2020–2021, employing burrow counts and burrow opening diameter as proxies for population abundance and population size structure.
- A total 6270 burrows were identified, counted and their opening diameter measured during the study period. The number of burrows was greatest close by the waterline and diminished landwards; this landwards decline was notable in the smallest burrows (<20 mm), representing the youngest population fraction. Comparison of population abundance between the surveyed nature reserves and adjacent bathing beaches revealed greater numbers in the former. However, a pronounced postweekend reduction in the number of burrows was apparent in nature reserves during both survey years, across sites and months and clearly indicates elevated recreational activity. The number of burrows in the nature reserve nearest to main population centres and abutting a popular bathing beach was smaller compared with the peripheral nature reserves.
- We observed no postsunrise activity of adult crabs, though in strictly access-restricted beaches, crabs were active diurnally. We thus suggest that the crabs shifted their diel activity patterns as avoidance response to chronic anthropogenic disturbance, enduring a forced curfew and a temporal habitat loss.
- If the sandy nature reserves are to function as true refugia for the tufted ghost crab, restorative management is to include significant conservation and mitigation intervention measurements/actions.
27.
Ulrich Gisi 《Plant pathology》2022,71(1):131-149
Fungal propagules existing in the natural environment can easily be transmitted to the human body, mostly by inhalation of contaminated air or direct contact onto the skin, nails, and mucosa. Fungal infections in humans are, as compared to viral and bacterial infections, rarely serious (life-threatening) unless the immune system is weakened. Because azole fungicides (demethylation inhibitors, DMIs) are among the most important antifungal compounds used broadly in human and animal medicine as well as in agriculture and material protection, fungal propagules may come into contact with azoles almost everywhere, presenting a potential “crossover-use-pattern” and “cross-contamination-risk” for resistant propagules in all areas. A “hot-spot” in terms of the emergence of azole resistance in a fungal species is defined as a habitat in which the species is actively propagating and exposed to a fungicidally effective azole at available concentrations high enough to select for resistant individuals, potentially multiplying and spreading to other habitats. Intrinsic antifungal resistance may exist in less sensitive or insensitive species independent of previous exposure to antifungal compounds, whereas acquired antifungal resistance can evolve if triggered by the exposure of an originally sensitive species (or population) to agricultural or medical antifungal agents, resulting in the selection of resistant individuals. The origin and risks of these developments in medical settings and the wider environment are elucidated for the most relevant life-threatening fungal human pathogens, including several species of Cryptococcus, Candida, Pneumocystis, Aspergillus, Histoplasma, Coccidioides, Rhizopus, Mucor, Fusarium, and Scedosporium. 相似文献
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29.
黄土高原降水资源特征与林木适宜度研究 总被引：2，自引：4，他引：2
黄土高原位于干旱半干旱地区,水资源匮乏,如何根据当地的降水条件来确定适宜的植被类型是生态建设中的一个关键问题.通过对黄土高原68个气象台站1961-2000年逐月降水量的统计,结果表明:黄土高原的降水特征总体表现为年平均降水量区域差异大,由东南部的大于600 mm逐渐递减到西北部的不足200 mm;植物生长期间的降水占全年80%以上,且季节分配不均,表现为春旱、夏多、秋少.依据黄土高原的降水资源特征,从林地水量平衡理论出发,以生长季期间林地的水分收支状况来确定林木的适生程度,并以县为单位对黄土高原的林木适宜性进行分区.结果表明,黄土高原适宜于乔木林和灌木林的区域各占1/4左右. 相似文献
30.
坚持环境与发展综合决策,努力解决吉林省通化县兴林镇曲柳川村经济社会发展及优美村屯建设过程中的生态破坏和环境污染问题,加强兴林镇曲柳川村生态环境的综合整治,努力改善生态环境质量,实现经济、社会和生态环境的可持续均衡发展。 相似文献