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近年来,绿色建筑成为国内乃至国际建筑界、房地产界的一个热点话题,绿色建筑的发展也越来越受到关注,许多国家都开展了绿色建筑的研究和实践,取得了很多的研究成果.尤其在去年经历了一场与"非典"的斗争之后,人类更加深刻地认识到绿色建筑在生活中的重要性,由此也引发了一场关于绿色建筑的革命,将绿色建筑向更深入、更科学的方向推进. 相似文献
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溶氧超标"毒水症" 危害及症状:水体中因施放过多未经发酵的肥料,生肥在塘底分解出很细小的甲烷和硫化氢的小气泡,鱼苗误当食物吞入.其主要症状是:鱼鳃上会粘附许多小气泡,使鱼体上浮或游动失去平衡.鱼的肠道中有白色气泡,或鱼的体表、鳍条、鳃丝上附有较多的气泡,鱼体漂浮水面,沉不下去,严重的可致鱼类成批死亡. 相似文献
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With the interpreted IKONOS4 satellite images collected in 2005,a 1:10 000 forest map,the data collected in ClassⅡforest survey in 2007,and surface runoff data obtained in the permanent runoff monitoring station,six site factors of slope gradient, slope position,soil thickness,soil thickness of A layer,soil type and soil water content were selected to establish a matter element model suitable to 297 forest sub-compartments.Further,the AHP was applied to modify the spatial structure and form the spatial para allocation of the protection forest system. The results showed that:1) the area allocation of different vegetation types was irrational,the area of a mixed coniferous and broad-leafed forest was 124.39 ha,accounting for 14.97%of the forested land,the mixed forest was consisted of two coniferous species accounted for 27.37%of the total forest land,and the pure forest was consisted of one coniferous species accounted for 42.48%.2) After optimization,the area allocation of different vegetation types in the protection forest system ranked as:the mixed coniferous and broad-leafed forest(31.12%)>shrub land(15.5%)>the economic tree crops(12.28%)>the mixed forest consisting of two coniferous species(11.46%)>the pure broad-leafed forest(11.41%)>the pure coniferous forest(9.51%)>grass land(8.70%). Besides,the annual surface runoff could reduce 43 171 mm or 62.15%,annual soil erosion could decrease 465.97 t or 79.66%.3) The following suggestions for spatial para allocation of the small watershed protection forest system were proposed: (1) Reducing pure cypress or pine forest,and increasing alder-cypress,oak-cypress or pine-cypress mixed forest.As for the current cypress and pine pure forests,alder or oak could be introduced to develop a mixed forest.(2) The canopy closure of pure cypress forest and alder-cypress forests should be maintained within 0.60-0.75,and the canopy closure of oak-cypress,pine-cypress or oak-pine forests should be controlled within 0.60-0.80. (3) For improvement of current pure 相似文献
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中小企业财务管理面临的问题及对策 总被引：3，自引：0，他引：3
中小企业是中国国民经济的重要组成部分,在国家经济生活中占有极其重要的地位.中小企业要快速、稳定、健康地发展,必须要清醒地认识到财务管理在企业经营中的重要地位和作用,本文针对当前我国中小企业财务管理方面存在的问题,从几个方面进行了分析,并提出了相应的措施. 相似文献
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The carbon cycle of forest ecosystems plays a key role in regulating CO2 concentrations in the atmosphere. Research on carbon storage estimation of forest ecosystems has become a major research topic. However, carbon budgets of subtropical forest ecosystems have received little attention. Reports of soil carbon storage and topographic heterogeneity of carbon storage are limited. This study focused on the Jinggang Mountain National Nature Reserve as an example of a mid-subtropical forest and evaluated soil and vegetation carbon storage by field sampling combined with GIS, RS and GPS technology. We classified the forest into nine forest types using ALOS high-resolution remote sensing images. The evergreen broad-leaved forest has the largest area, occupying 26.5% of the total area, followed by coniferous and broad-leaved mixed forests and warm temperate coniferous forest, occupying 24.2 and 22.9%, respectively. The vegetation and soil carbon storage of the whole forest ecosystem were 1,692,344 and 5,514,707 t, with a carbon density of 7.4 and 24.2 kg/m^2, respectively, which suggests that the ecosystem has great carbon storage capacity. The topographic heterogeneity of the carbon storage was also analysed. The largest vegetation storage and soil storage is at 700–800 and 1000–1100 m, respectively. The vegetation carbon storage is highest in the southeast, south and southwest. 相似文献
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《绿色中国(A版)》2009,(Z1)
前两天,在一家网站的涂鸦馆里看到这样一幅图画:一个小牛形状的面包被切成几片站立在我的面前。作者为它的创意起了一个名字叫"分享",意思是面包要一起食用。图画下面一位网友的跟帖引起了我的注意。 相似文献
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我国蓝莓研究 总被引：1，自引：0，他引：1
从蓝莓生产、繁殖、育种等角度综述了我国蓝莓研究现状,并提出今后蓝莓研究热点。我国虽然开展了一定规模的蓝莓种植,但栽培技术不高、效益不好是制约我国蓝莓生产的重要因素,尤其是内蒙古大兴安岭地区极具优势的野生蓝莓栽培生产尚未成熟是一件十分遗憾的事;从繁殖方式上看只有少部分品种实现了快繁,有较多的优良引进品种的快繁体系尚未建立,所以快繁技术还有待于进一步完善,特别是内蒙古大兴安岭高寒地区野生蓝莓的快繁技术的研究还处于研究阶段;种子繁殖正处于起步阶段;蓝莓育种技术的研究在我国尚属空白,生产中使用的品种均为引进种,这些品种耐寒性差,越冬防寒技术要求高是栽培推广的限制因素,而内蒙古的野生蓝莓品种虽然耐寒性强,但产量低、果实贮藏性差、栽培成活率低也是生产中的棘手问题,因此,选育出我国自主蓝莓品种是当务之急,尤其以大兴安岭高寒地区野生蓝莓为基础的新品种培育将成为今后我国蓝莓研究的重要方向。 相似文献
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The most common trees on farm homesteads in Bangladesh were bamboo (several spp.), jackfruit (Artocarpus heterophyllus), mango (Mangifera indica), betelnut (Areca catechu), and jujube (Zizyphus jujube) in all agroecological zones studied. There were regional differences in the less common species. Species for new homestead
planting were chosen mainly by women and tended to include indigenous fruit trees and a few exotics of high timber value.
Choices were later influenced by new experience with exotic tree species and by perceptions from secondary information sources.
Farmer-managed action-research was used to test the survival and performance of new trees planted under the Village and Farm
Forestry Programme (VFFP). The main factors influencing tree survival were the role of women in selection of species and planting
site, the degree of personal attention paid aftercare by the owner, and the quality and size of the planting stock. Biophysical
factors and agroecological zones were unimportant. Main recorded causes of tree mortality were, in order of importance: damage
by livestock, pests or diseases, physical damage by people (mainly children playing), and drought. Cause of death could not
be attributed in about 35% of mortality, suggesting that the recorded causes should be treated with caution.
Previous articles 1 and 2 in the series appeared in Agroforestry Systems 25: 193–216 and 31: 39–57 with slightly different
main titles. 相似文献
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Seasonal yields of wetland rice and wheat were measured under traditionally-managed field trees of five species in northwestern
Bangladesh over four years. There was a variable depression of rice (Oryza sativa) and wheat (Triticum aestivum) yields under all tree species. Yield depression overall ranged from 16% for the light-canopiedAcacia catechu to a little over 40% for the dense-canopiedArtocarpus heterophyllus andMangifera indica. Percentage yield depression was independent if agroecological zones, years, and location of the trees on the margins of
centrally in a field. Yield depression in the dry season extended further in area than in the wet season; and for most tree
species was to some extent alleviated by availability of irrigation. Farmers were well aware of and accepted crop yield losses
under different tree species in return for the tree products. Trees with greatest impact on crops yielded products of highest
value, mainly fruits and leaf fodder.
Previous articles 1, 2 and 3 in the series appeared in Agroforestry Systems 25: 193–216, 31: 39–57 and 33: 231–247 respectively,
with slightly different main titles. 相似文献
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基于水经注探讨乌兰布和沙漠景观形成问题 总被引：1，自引：0，他引：1
根据北魏时期郦道元地理名著《水经注》中关于乌兰布和段黄河故道及其与黄河沿岸古城的位置关系,修正了有关现在黄河河道来源、沃野故城被黄河改道冲毁等论断,并从沙源与沙漠内涵、地表大面积流沙裸露堆积形成沙漠景观以及《水经注》中没有记录乌兰布和段沙漠景观等方面探讨了在乌兰布和沙漠景观的形成时间问题。 相似文献
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对当前绿化造林中出现一些问题的思考 总被引：1，自引：0，他引：1
对本市绿化造林中出现的新问题，提出了宜采取的对策，旨在引起领导的关注和有关部门的重视，以促进宁波市林业事业的持续，快速，健康发展。 相似文献
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大庆苏打盐碱地造林研究 总被引：1，自引：0，他引：1
本研究采用田间试验法,应用微生物肥料进行植树造林,栽植树木为16个品种。在不同时间内,采集植物和土壤样品,分别测定树木的形态、生理生化等指标;测定土壤物理、化学参数。经过2004-2007年连续4a的野外观测,通过对比施用活性微生物菌肥与不施用肥料的盐碱土上种植乔木和灌木等绿化树种生长状况进行研究。结果表明,施用活性微生物菌肥的乔木、灌木在成（存）活率、生物量、乔木胸径、新梢生长量、叶绿素含量、根系发育和生长势等各个方面均明显优于对照树木。因此,有望应用活性微生物菌肥在盐碱地的造林方面进行推广。本试验证明微生物肥料可以在盐碱土中广泛使用,在一定程度上能改善盐碱土的理化性质,提高土壤肥力,促进树木的生长。 相似文献