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221.
下山桩过渡栽培技术的研究 总被引:5,自引:3,他引:2
为了保证下山桩能够成活、提高其成活率并形成树桩的骨架,从素材选择、采掘、过渡栽培3方面研究了新掘树桩的过渡栽培技术。 相似文献
222.
温室有砂育鳖的水质恶化是育鳖中经常遇到的棘手问题。采用光合细菌 (PSB)、硝化细菌 (NB)、玉垒菌 (S30 )等有益微生物进行温室有砂育鳖 ,结果表明 ,有益微生物联合使用可以有效分解底泥中污染物 ,去除水体中的有机物、氨氮、亚硝态氮 ,减少换水次数 ,节约用水量 ,并起到保护环境的作用 相似文献
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Market‐based, supply‐side interventions such as domestication, cultivation, and wildlife farming have been proposed as legal substitutes for wild‐collected plants and animals in the marketplace. Based on the literature, we devised a list of the conditions under which supply‐side interventions may yield positive conservation outcomes. We applied it to the trade of the orchid Rhynchostylis gigantea, a protected ornamental plant. We conducted a survey of R. gigantea at Jatujak Market in Bangkok, Thailand. Farmed (legal) and wild (illegal, protected) specimens of R. gigantea were sold side‐by‐side at market. These results suggest farmed specimens are not being substituted for wild plants in the marketplace. For any given set of physical plant characteristics (size, condition, flowers), the origin of the plants (wild vs. farmed) did not affect price. For all price classes, farmed plants were of superior quality to wild‐collected plants on the basis of most physical variables. These results suggest wild and farmed specimens represent parallel markets and may not be substitutable goods. Our results with R. gigantea highlight a range of explanations for why supply‐side interventions may lack effectiveness, for example, consumer preferences for wild‐collected products and low financial incentives for farming. Our results suggest that market‐based conservation strategies may not be effective by themselves and may be best utilized as supplements to regulation and education. This approach represents a broad, multidisciplinary evaluation of supply‐side interventions that can be applied to other plant and animal species. Un Marco de Referencia para Evaluar la Oferta de la Conservación de Vida Silvestre 相似文献
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Abstract For natural resource science, resource productivity studying is an important subject. But researches on tourism resource productivity are limited. The most significant influencing factor on tourism resource productivity is the potential market scale of tourist locations, and second most important influencing factor is the resource endowment. Regional urban population is significantly correlated with region tourist numbers, being the decisive factor of region potential tour market scale. In tourism development, the dual model should be adopted: on one hand to enhance tour spot attractiveness, on the other hand to cultivate the potential market by improving urbanization level and other means. In the situation of tourism development fever spreading, the dual model for improving tourism productivity helps to avoid the “Great Leap Forward” which means that too rapid tourism construction divorces from actual market demand. 相似文献
227.
R. K. Sinha 《国际发展与全球生态学杂志》2013,20(4):278-284
SUMMARY In India, since ancient times, several members of the flora and fauna have been identified with particular personalities of the Hindu pantheon and are worshipped. Many wild animals, such as tigers, lions and elephants, and birds such as the peacock, owl and swan have been revered as the vehicles of Gods and Goddesses and worshipped. Several trees, such as mango, coconut, khejri, emblica, tamarind, ashoka, madhuca and wood apple, and herbs such as basil are considered highly sacred and worshipped. This belief and these practices continue in one form or another even today in certain sections of Indian society, particularly the rural folk and the aboriginal tribes living in the forest. Nature worship is a form of tribal belief and the faith of these laymen has helped to conserve many natural ecosystems in India. They have preserved many pristine forests—called ‘sacred groves’ in their original forms. Sacred groves are rich in biodiversity. They are the last refuge of the rare flora and fauna which have otherwise disappeared from the modern world. Sacred groves have become part of the ‘biosphere reserves’ of India. 相似文献
228.
王微 《中国环境管理干部学院学报》2006,16(3):70-74
中国环境管理干部学院在各项工作中实践着特色育人的思想.学院坚持“以服务社会需求为导向,以提高教育教学质量为核心,以培养高素质、高技能人才为根本,培养大学精神,积淀大学文化,铸就大学灵魂,彰显环境教育特色,创建绿色和谐校园“的办学理念,发挥了环境教育特色所带来的优势,注重遵循教育发展的规律,取得了可喜的办学成绩. 相似文献
229.
采用厌氧颗粒污泥为接种污泥,在SBR反应器内培养好氧颗粒污泥,并对其微观特征进行了研究。COD负荷为1.5kg/m3·h~1.8kg/m3·h,表面气体流速在0.0052m/s之间,沉淀时间控制在10~8min时,有利于好氧颗粒污泥的形成。20d后完成好氧颗粒污泥的驯化和培养。研究发现培养的好氧颗粒污泥微生物相以杆菌和丝状菌为主,球菌较少。用扫描电子显微镜(SEM)观察好氧颗粒污泥的微观结构,颗粒污泥具有不平整的表面,轮廓清晰,表面有薄层粘液覆盖并有绒毛状结构。颗粒污泥表面和内部有明显的孔洞或孔隙。研究结果表明,好氧颗粒污泥具有良好的有机物降解能力和同步硝化反硝化能力。 相似文献
230.
无土栽培植物对农村生活污水的净化特性研究 总被引:4,自引:0,他引:4
选取水烛、石菖蒲和黄菖蒲三种挺水植物作为无土栽培系统的培养物,通过动态试验进行农村生活污水处理对比研究。结果表明:相对对照系统,三种植物对农村生活污水均具有较好的适应性,生长量石菖蒲>黄菖蒲>水烛;处理系统对COD、NH+4-N和TN的去除效果依次为石菖蒲>黄菖蒲>水烛>对照;对TP的去除率依次为水烛>黄菖蒲>石菖蒲>对照。同时,通过对处理系统去除氮磷途径的分析,发现植物吸收作用是主要去除方式,沉淀吸附也起着重要的作用。综合三种植物的净化能力,认为石菖蒲更适合无土栽培处理系统。 相似文献