浅析屋顶花园的生态功能   总被引：1，自引：0，他引：1  

贾永亮  王东焱 《现代园艺》2011,(11):140-141

以屋顶绿化为研究对象,探讨屋顶绿化的生态功能。屋顶绿化具有降低能源消耗、缓解"热岛"效应、雨水收集、改善屋顶的物理性能、降温降燥、增加CO2固化效果、保护生物多样性等生态功能。屋顶绿化生态效益明显,顺应可持续发展的潮流,将会成为本世纪的重要产业之一。  相似文献   

西安城市热岛的时空分布特征   总被引：4，自引：1，他引：3  

董妍  李星敏  杨艳超  彭艳  王繁强  杜川利 《干旱区资源与环境》2011,(8):107-112

选取1959-2008年西安市常规气象站和城区加密自动站逐小时气温资料,采用城、郊气温对比法研究西安城市热岛效应的时间变化和空间分布。结果表明：西安城市热岛效应逐年增加,具有明显的季节变化特征;热岛强度日变化呈现双峰分布,两个峰值分别出现在05时和21时左右,最低值出现在11时左右。在西安市城区一直存在一个强城市强热岛...  相似文献   

沙漠水渠人工固沙区沙篙和沙拐枣灌丛的土壤水分特征对比   总被引：1，自引：0，他引：1  

侯建秀  张元明  陶冶  全永威  李铭杰  杜晓虎 《干旱地区农业研究》2011,29(4):164-167

在古尔班通古特沙漠引水渠沿线建植5a的人工固沙区内,选择自然生长的沙蒿和沙拐枣灌丛,依据冠幅大小设置5个水平距离梯度和4个土层深度梯度.对比研究了二者的土壤水分特征.结果表明,随土层深度的增加,两种灌丛土壤含水量均呈增加趋.,中下部2层(20～40 cm和40～60 cm)土壤含水量显著(P<0.05)高于上部2层(0...  相似文献   

Conservation biology for suites of species: Demographic modeling for Pacific island kingfishers     

Dylan C. Kesler  Susan M. Haig 《Biological conservation》2007,136(4):520-530

Conservation practitioners frequently extrapolate data from single-species investigations when managing critically endangered populations. However, few researchers initiate work with the intent of making findings useful to conservation efforts for other species. We presented and explored the concept of conducting conservation-oriented research for suites of geographically separated populations with similar natural histories, resource needs, and extinction threats. An example was provided in the form of an investigation into the population demography of endangered Micronesian kingfishers (Todiramphus cinnamominus). We provided the first demographic parameter estimates for any of the 12 endangered Pacific Todiramphus species, and used results to develop a population projection matrix model for management throughout the insular Pacific. Further, we used the model for elasticity and simulation analyses with demographic values that randomly varied across ranges that might characterize congener populations. Results from elasticity and simulation analyses indicated that changes in breeding adult survival exerted the greatest magnitude of influence on population dynamics. However, changes in nestling survival were more consistently correlated with population dynamics as demographic rates were randomly altered. We concluded that conservation practitioners working with endangered Pacific kingfishers should primarily focus efforts on factors affecting nestling and breeder survival, and secondarily address fledgling juveniles and helpers. Further, we described how the generalized base model might be changed to focus on individual populations and discussed the potential application of multi-species models to other conservation situations.  相似文献   

平潭海岛防护林的减灾稳产效益     

卢成林  陈昌茂 《福建林学院学报》1992,12(1):121-124

本文报导了平潭县营造海岛防护林、经济林的成功经验,详述了海岛防护林在防风固沙、经受台风袭击中所发挥的防护作用及其所带来的经济效益。  相似文献   

Surgical management of a malacic corneal ulcer in a greater one-horned Asian rhinoceros (Rhinoceros unicornis) using a free island tarsoconjunctival graft     

Esson DW  Wellehan JF  Lafortune M  Valverde A  Citino SB 《Veterinary ophthalmology》2006,9(1):65-69

A greater one-horned Asian rhinoceros (Rhinoceros unicornis) presented for presumed ocular trauma to the left eye, with secondary bacterial infection, resulting in severe and progressive corneal ulceration. Following a poor response to medical therapy, the animal was anesthetized for further examination, and a bulbar conjunctival pedicle graft performed. This graft failed by 48-h postsurgery as a result of self-trauma. The animal was re-anesthetized, and a free island tarsoconjunctival graft performed. This second procedure was successful, resulting in globe preservation, cosmesis, and functional vision in the affected eye.  相似文献   

利用Red重组系统敲除APEC毒力岛irp2基因     

李叶芳  涂健  邵颖  刘红梅  祁克宗 《安徽农业大学学报》2012,39(6):854-858

应用质粒pKD46介导的Red同源重组系统,以质粒pKD3为模板,设计irp2基因序列敲除引物,引物5'端有51 bp的拟敲除基因的同源臂,3 '端为扩增引物,扩增两侧含FRT位点的氯霉素抗性基因,通过第1次同源重组将拟敲除的irp2基因替换为氯霉素抗性基因,再通过重组酶质粒pCP20在FRT位点发生第2次同源重组,消除抗性基因.结果表明,利用该重组系统成功敲除了禽致病性大肠杆菌HPI毒力岛irp2基因.为深入研究irp2基因在禽致病性大肠杆菌致病过程中所发挥的作用打下基础.  相似文献   

郑州市热岛效应、植被变化与林业发展对策研究     

邱尧荣  孙伟韬  赵磊 《华东森林经理》2012,(3):56-58

利用郑州市 TM 卫星影像相并波段数据,研究郑州市的地表亮温和 NDVI 植被指数与植被盖度情况,发现该市相对亮温等级以弱热岛和中等热岛为主,绿岛面积仅占16.44%,且主要分布在郑州市防风固沙林面积较多的东部区域、森林面积较多的西南山地及沿黄河湿地地带,进而提出科学合理布局城市林业,防止并减缓“热岛效应”的林业发展对策.  相似文献   

断奶仔猪源产Vero细胞毒素大肠杆菌eaeA基因的检测     

成大荣  徐建生  孙怀昌  高崧 《畜牧与兽医》2005,37(8):14-16

根据文献合成了一对引物,利用PCR方法检测了84株来自断奶仔猪水肿病例的产Vero细胞毒素大肠杆菌(VerotoxigenicEscherichiacoli,VTEC)的LEE(locusofenterocyteeffacement)毒力岛的eaeA基因,以了解携带LEE毒力岛的大肠埃希菌在江苏省断奶仔猪群VTEC中的流行状况。结果发现:从其中17株中可扩增到预期的DNA片断,证实它们携带LEE毒力岛,携带率为20.24%。数据分析提示:LEE毒力岛的分布不仅限于EPEC和EHEC,在断奶仔猪源VTEC中也有一定的分布,并可能成为重要的毒力因子。  相似文献   

基于绿色会计的海南国际旅游岛建设研究     

李盛林 《安徽农业科学》2013,(17):7596-7598

研究基于绿色会计的视角,对海南国际旅游岛的建设进行了探索性的分析,通过文献分析与实地调研相结合的方法,认为海南国际旅游岛的发展必须重视绿色理念、绿色政策、绿色人才的完善。国际旅游岛的建设应以绿色认知为先导,以绿色会计理论为载体,以政府政策制定为保障,通过社会各方主体的共同追求而实现。研究旨在为完善绿色会计理论起到强化作用,有助于国际旅游岛的建设研究。  相似文献