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《新疆环境保护》2017,(2)
植被对荒漠绿洲交错带的水土保持和生态系统恢复具有重要意义。通过LI-6400XT光合系统对准噶尔荒漠绿洲交错带的7种早春短命植物和7种典型荒漠灌木的光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)与水分利用效率(WUE)进行测定,结果表明:所观测的14种植物的光合速率差异较大,其中7种早春植物平均光合速率为29.6μmol CO_2/m~2·s;7种荒漠典型灌木的为11.2μmol CO_2/m~2·s;短命植物和荒漠灌木的Gs与Pn呈负相关关系,相关系数分别为-0.81和-0.69,Tr与Gs之间的响应趋势都存在正相关系;在适合的水分条件下,7种命植物的Pn要显著高于7种荒漠灌木的,表现出更高的光合潜能。 相似文献
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四种短命植物若干生态学特性的研究 总被引:5,自引:0,他引:5
1.前言短命植物是温带荒漠地带重要的植物类群之一,通常被定义为:生长发育周期短暂,在春末夏初约两个月左右的时间内迅速完成全部生长周期的一年生草本植物,主要分布于北非、西亚、中亚、北美、南美和澳大利亚等广大地区的干旱荒漠中,亦存在于部分草原、山地草甸和山地林中,以苏联中亚地区较为繁茂,在我国,短命植物主要分布于新疆西北部荒漠及毗邻的草原植被中,局部地段可构成优势层片,甚或形成群聚,从而使北疆植被显著区别于我国其 相似文献
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对山海关滨海盐生植物及盐生植被景观和群落配置情况进行实地调查并参考历史文献,发现山海关滨海湿地共有盐生种子植物26科44属51种。结合山海关海岸带的气候、土壤理化性质及土地覆盖和利用的现状,选择乔、灌木类盐生植物3种,藤本类盐生植物1种,中生草本盐生植物5种,旱生草本盐生植物2种,湿生植物4种,共计15种作为滨海地区盐碱地改良和植被恢复的野生植物种类。 相似文献
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黄山市分布有49种国家级保护植物。依据药用、食用、材用、绿化观赏、芳香、栲胶等利用价值和科学研究价值将它们分为7类,阐述了各类代表植物的利用价值,对黄山市国家级保护植物的保护措施和开发利用提出建议。 相似文献
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一珍稀濒危植物是指植物在科学研究、经济文化等方面具有重要意义的珍贵、稀有、受威胁、濒临灭绝的种类。据估计,在全球约25万种维管束植物中,处于稀有或受严重威胁状况的植物不少于2.5万种,占10%以上。我国的植物资源相当丰富,现估计在大约3万种高等植物中有3000种(即占10%的种类)处于这种状态。目前世界上把受威胁的植物分为渐危、稀有、濒危三大类。我国也 相似文献
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笔者通过多年调查研究,初步统计了江西药用维管植物约有2400种,隶属166科665属,并分析了各属的区系成分。根据药用植物的用途和药用价值,将它们分成5类,即中草药植物、兽用药用植物、土农药植物、观赏药用植物和珍稀濒危药用植物。分别叙述了各类药用植物的主要种类,为江西药用植物资源合理利用与保护提供了有关科学依据。 相似文献
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秦皇岛市地处北温带,其气候温和,地貌齐全,自然条件复杂,植物资源丰富多样,据调查统计有高等维管植物1682种,隶属167科,746属,其中栽培种有570种,野生种1112种,有珍稀濒危保护野生植物12种.目前,泰皇岛市的植物资源还未充分开发利用,不同程废的毁林开荒和过度放牧等现象时有发生.有关部门对此应引起高度重视.建议:①将老岭建成自然保护区;②加强对珍稀濒危植物的保护和管理工作;③进一步开发利用中草药资源;④结合旅游事业大力发展果品加工;⑤重视山珍海味的利用和发展;⑥加强沿海滩涂的开发利用;⑦开展 相似文献
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城镇化是推动我国经济社会发展的重要动力,在高速发展的同时,带来大量污染排放,威胁乡村环境质量与可持续发展。在对乡村生态环境问题剖析的基础上,从战略、实施、方式等层面探索解决思路,围绕科学规划、发展方式、基础建设、管理机制、宣传教育等方面分析关键点,加强乡村环境保护,保障城镇化建设健康发展,为促进农村农业持续发展提供持久动力。 相似文献
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Trametes versicolor decolorized 2000 mg L(-1) of the mono-azo substituted naphthalenic dye Amaranth with no dye sorption observed visually. The changes in the toxicity were assessed over a period of 30 d for the dye-treated viable culture, control (no dye added), and a boiled culture treated with dye, using the Microtox Acute Toxicity assay. Before dye addition, the culture filtrate had some toxicity, which increased after the dye addition. The toxicity of the dye-treated culture decreased during the treatment. The loss of toxicity occurred at the same time, with the loss of color suggesting that detoxification is associated with decoloration. The change in pH was due to natural metabolic processes and had a small effect on detoxification. Because the toxicity of the treatment was similar to that of the control at the end of the treatment, the effluent seems to be safe for release into the environment, potentially rendering this treatment suitable for industrial application. 相似文献
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泵站树状给水管网流量具有随机性,而这种随机性变化会直接影响管网的建设费用和动力费用.针对这-特点,应用随机规划原理,建立泵站树状给水管网机会约束模型,编写基于随机模拟的遗传算法程序求解该模型.机会约束模型能较客观地反映该管网的实际工况,使优化设计结果更符合实际. 相似文献
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Günay Kocasoy 《Environmental management》1989,13(4):469-475
The increase in the number of tourists visiting a coast is desired by most of the countries for economic reasons. However, this increase in tourism may cause pollution of the sea. This can be only avoided by proper planning and by predicting the carrying capacity of the coast in terms of sea pollution. This is especially important for developing countries where part of the wastewater is discharged without any treatment into the sea.In the present study the beaches were classified according to their use — and consequently the amount of waste discharged into the sea — into four groups: (1) coasts that are used only for swimming and recreational purposes; (2) coasts used simultaneously for dwelling, swimming, and recreational purposes; (3) coasts along which only dwellings exist; and (4) natural and man-made harbors, i.e., coasts used as shelters. During the survey,40,320 observations were made between December 1985 and February 1988 to determine the effect of the number of tourists on seawater quality. The results obtained were analyzed by a multilinear regression program to obtain an empirical equation giving the extent of the sea pollution in terms of coliform concentration as a function of population density and some other environmental factors.The equations derived in this study enable the determination of the carrying capacity of a beach in terms of pollution as well as the expected degree of pollution corresponding to a given population density. Furthermore, it allows the prediction of the extra carrying capacity that can be obtained by improving the waste-disposal conditions. 相似文献
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阐释了信息产业专门化街区的内涵,结合对合肥市黄山路信息产业专门化街区构成要素的分类及其邻近度的分析,分别从空间结构演化、景观演化、功能演化三方面阐述了合肥市黄山路由"电子一条街"向"信息产业专门化街区"的总体演化阶段,探讨了信息产业专门化街区的未来发展趋势。 相似文献
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