论西部大开发中张掖市生态环境建设问题   总被引：3，自引：0，他引：3  

冉永军  丁丽萍  李庆会  郭宝琴  蔡建英 《干旱地区农业研究》2003,21(2):159-162

张掖市长期受干旱、大风及沙尘暴影响,生态环境极为恶劣,制约着西部大开发建设进程。其存在的重要问题是:水资源匮乏,植被破坏严重,覆盖率低等;针对具体情况提出:改善水资源条件和恢复植被是张掖地区生态环境建设的重点。  相似文献   

大型综合医院户外空间植物景观研究     

丁晓浩  李晓婷 《黑龙江农业科学》2014,(6):93-96

为营造良好的医院户外空间,采用文献查阅和综合分析等方法对广州市3家大型综合医院的绿地植物景观进行研究。结果表明:3家医院共有植物116种,其中骨干树种和基调树种的重复率较高,乔灌比值偏小,常绿与落叶比相对合理,色彩应用设计合理。在交往空间的搭配中,广东省中医院的交往空间最丰富,广东省人民医院私密型空间较少,中山大学第一附属医院对病人户外交往空间考虑不够,空间应用的元素较为单一。  相似文献   

Effect of Prosopis (mesquite) invasion and clearing on vegetation cover in semi-arid Nama Karoo rangeland,South Africa     

Thabisisani Ndhlovu  Suzanne J Milton  Karen J Esler 《African Journal of Range and Forage Science》2016,33(1):11-19

The Nama-Karoo is the largest of the three biomes that comprise the semi-arid Karoo-Namib ecoregion of southern Africa. Large tracts of Nama-Karoo rangeland have been invaded by alien leguminous trees of the genus Prosopis. We assessed the impact of Prosopis invasion and clearing on vegetation cover in heavily grazed Nama-Karoo rangeland on two sheep farms in the Beaufort West district of the Western Cape province of South Africa. Our results suggest that, below critical threshold cover levels, Prosopis trees do not affect indigenous vegetation and add to overall rangeland vegetation cover. However, once Prosopis cover exceeds critical thresholds, the trees begin to negatively impact on indigenous vegetation (especially grasses) and overall vegetation cover. In addition, our data suggest that vegetation cover recovers after Prosopis clearing, being temporarily higher than pre-invasion levels possibly as a result of enhanced post-invasion soil fertility. Lastly, our results suggest that Prosopis trees reduce rangeland erosion potential at low cover and increase it after they exceed critical threshold cover. Information about thresholds of Prosopis impact can be used to direct clearing efforts for maximum benefit when resources are limited.  相似文献   

Veterinary Spinal Manipulative Therapy or Animal Chiropractic in Veterinary Rehabilitation     

《Veterinary Clinics of North America: Small Animal Practice》2023,53(4):757-774

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Rehabilitation Therapy for the Degenerative Myelopathy Patient     

《Veterinary Clinics of North America: Small Animal Practice》2023,53(4):845-856

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Modernization of furrow irrigation in the South-East of France automation at field level and its implications     

D. Renault 《Irrigation and Drainage Systems》1988,2(3):229-240

Surface irrigation rehabilitation in the South-East of France has shown success ever since the beginning of its development in the early 1980s. The gradual introduction of surface distributors, mechanized or automated has resulted in water savings and above all in decreased labor input. The distributors used are: gated pipes, layflat tubing, buried low pressure pipe and cablegation. They are used over an ever increasing area which attained about 1000 ha in 1987.Improvement is made in furrow head distribution as well as in field levelling, furrow flow evaluation, flow control at the head of the furrow and in the collective system.The effect of a modernized system and improved knowledge has been to make automated surface irrigation (particularly furrow irrigation) a modern application method in competition with techniques such as sprinklers and localized irrigation.Abbreviations ASAE American Society of Agricultural Engineers - CEMAGREF Centre d'Etude du Machinisme Agricole du Génie Rural des Eaux et des Forêts, Division Irrigation, BP 5095, 34033 Montpellier et BP 31 Le Tholonet 13612 AIX - ENGREF Ecole Nationale du Génie Rural des Eaux et des Forêts, Département Maîtrise de l'Eau et Développement, BP 5093, 34033 Montpellier - IRAT Institute de Recherche en Agronomie Tropicale, Zolad Mini Parc Bt7, 34100 Montpellier - P.V.C. Polyvinyl chloride - RNEDHA Réseau National Expérimentation Démonstration secteur Hydraulique Agricole, BP 5095, 34033 Montpellier - SCP Société du Canal de Provence et d'Aménagement de la Région Provençale, BP 100, 13603 AIX en Provence  相似文献   

农村污染缓流水体的修复研究   总被引：2，自引：0，他引：2  

周小锋  田晖 《中国农村水利水电》2007,(5):43-45

农村缓流水体是维系乡村生态平衡的重要组成部分, 水质污染已成为国内乡村缓流水体普遍现状。讨论了农村缓流水体的污染成因，并以水生植物大漂为水体修复主体，进行了大漂的水体修复特性的试验，讨论了在可控条件下用大漂对缓流污染水体进行修复治理的植物修复技术及大漂在水体修复中可能带来的生态风险及其防范。  相似文献   

长兴县煤山镇矿山复绿及景观再现研究     

方何斌  蒋文伟  郭慧慧 《中国园艺文摘》2010,26(12):118-119

分析长兴县煤山镇矿山复绿及景观再现所采取的措施，主要是坡体采用生态石笼护坡技术，边坡挂网技术和混合喷播技术；石壁采用喷混植生技术。引入适宜矿山复绿的植物品种，并借鉴国外相关领域的成功经验，结合矿山的实际情况，尽可能的形成生态景观，以求获得最大的生态效益、社会效益和景观效益。  相似文献   

山西平朔ATB矿退化土地的林业复垦与生态重建研究   总被引：5，自引：0，他引：5  

张震云  张亚昌 《山西林业科技》2000,(2):17-23,27

采用调查、类比、室内模拟和野外试验示范相结合的方法，１９８７年－１９９９年在山西平逆ＡＴＢ矿进行了林业复垦与生态重建研究，结果表明。该矿生态系统演谱分为生态系统破损阶段、生态系统雏形建立阶段和生态系统动脉平衡阶段；生态受损引发因子包括土地挖损、土地压占、土地占用和土地污染；生态重建的实质为林业复垦基础工程的再造与植被重建工程的实施；生态重建的关键技术包括排土场的设计、有毒物质的消除、黄土的覆盖、侵蚀的控制、植物筛选与配置；重建后的生态优于采矿前的原生态。  相似文献   

不同退耕模式林草初夏小气候效应   总被引：5，自引：0，他引：5       下载免费PDF全文

姜艳  徐丽萍  杨改河  任广鑫 《干旱地区农业研究》2007,25(2):162-166

通过对安塞县几种不同类型退耕还林还草模式,如混交林、人工灌木林、野生灌木林及林中革地进行了小气候观测,分析了不同退耕模式林草配置下的主要小气候特征,采用平行对比观测法定点定时观测了空气温湿度,土壤温度,水面蒸发并与对照裸地进行了对比.结果表明4种不同退耕模式林草配置在6月高温时期能显著降低空气温度和地表温度的日均值,提高空气湿度和土壤湿度,减少水面蒸发等,具有明显的调节功能.4种不同退耕模式日平均空气温度变化呈不对称的单峰曲线,较对照裸地可以降低0.41℃～1.2℃;0～20 cm各深度的土壤温度基本都是混交林＜人工灌木林＜野生灌木林＜林中草地＜对照裸地,混交林内地面最高温度为34.78℃,明显比对照裸地42.54℃低;空气相对湿度日动态呈"U"型变化,其中对照裸地相对温度日均值最低,混交林日均值最大,为55.2%,比对照裸地高3.95%;水面蒸发量为裸地最大,混交林及灌木林能有效减少水面蒸发,减少量较对照裸地可达50.54%和55.20%.  相似文献