石林保护区所在地域经济发展评析

文章在了解石林保护区基本概况的基础上，重点评析了保护区所在地域经济发展水平，产业结构和存在的问题，进而提出了相应的对策。     

Diversity of leaf-litter anurans in a fragmented landscape of the Atlantic Plateau of São Paulo State,southeastern Brazil

Brazil is a tropical country and has the greatest anuran species richness in the world: the Atlantic Forest has roughly half of these species. We contribute to the knowledge of the anurans of the Brazilian Atlantic Plateau, determining the composition of anuran fauna associated with leaf litter in six landscapes, patterns of spatial distribution and levels of similarity among these landscapes and other communities. The sampling by pitfall traps was conducted in São Paulo state, at a total of 68 sites distributed among continuous and fragmented landscapes. The anuran fauna of these sites is typical of dense ombrophilous forest, and the composition resembled those of other localities of the Atlantic Forest. A cluster analysis comparing the six landscapes resulted in three main groups (Caucaia + Reserva do Morro Grande; Tapiraí + Ribeirão Grande; Fazenda Paraíso + Parque Estadual Jurupará). In the cluster analysis comparing these faunas to those of other localities, we could not find an effect of geographic distance on the differences in composition among areas.     

一类生态系统演化模型的极限定理及其应用

生态系统演化模型有着重要的应用.首先定义了一类生态演化模型,然后给出了时间趋向于无穷大时,系统的总人口数的期望是爆炸(即为无穷大),还是灭绝(即为有限)的充分必要条件.并且作为一个应用,证明了系统的总人口数的期望有限等价于一类随机游动具有一个正速度.     

贵阳二环林带主要造林树种生物学特性研究

采用野外调查和野外观察方法对贵阳二环林带主要造林树种:猴樟、杜英、银杏、香樟、紫薇、刺槐、川黄柏、大叶女贞、栾树、杜仲和南酸枣的形态学特性和生长状况等生物学特性进行了研究,研究发现它们对项目区的气候、水分、土壤因子等均能表现出较强的适应性.     

多种群捕食-竞争系统的持久性和稳定性

通过构造Liapunov函数,讨论了一类多种群Lotka-Volterra混合系统,得出该系统一致持续生存和全局渐近稳定的充分条件。     

Existence and Stability for Periodic Solution of Cooperation Ecosystem with Diffusion

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Existence and Stability of Positive PeriodicSolution of Delay Logistic Ecosystem with Feedback Control and Diffusion

1IntroductionWeconsiderthedelaylogisticecosystemwithfeedbackcontrolanddiffusionoftheformConcerningthestabilityproblemofpositivestead-stateforsystem(1.1),ithasbeendiscussedbyX.Shengli[1],whereastheasymptoticbehaviorofsolutionsofsystem(1.1)withoutdiffusionhasalsobeenconsideredbyK.Gopalsamy[2]andtheoscillationofsystem(1.1)withoutdiffusionandfeedbackcontrolcanbefoundinreference[3](K.GopalsamyandG.Ladas),Inreference[4],J.Dangpinghasgivedsufficientconditionsofexistenceandstabilityofperiodicsolut…     

贵州、广西石炭纪晚期生物礁群落生态系统对比

为了深入认识石炭纪晚期生物礁的生物和环境因素对礁体发育的影响，通过礁群落生态和栖息环境两个方面，对贵州、广西石炭纪晚期造礁生物群落生态特征、生物因素对礁群落发育的影响、礁体发育背景和礁体建造规模的影响等方面进行对比研究.贵州猴场地区造礁生物群落中关键种优势地位明显，造礁生物生长迅速、统殖能力强，礁体规模大使得生物礁发育较成熟；广西浪平地区点礁中没有明显的关键种和优势种，造礁生物生态特点不突出、造礁能力弱，滩相环境影响显著和礁体规模偏小是其礁体发育差的直接原因.     

GEP核算实践探讨及研究展望

主要针对GEP核算的起源、发展、不足等方面进行概括和分析，系统阐述了国内外GEP核算代表性的研究成果，指出不同时期所提出GEP核算机制的缺陷。最后，提出国内GEP研究方向与发展趋势。     

海燕650B轻型飞机防治森林虫害作业技术研究

应用海燕６５０Ｂ轻型飞机，采用ＨＹ－１型风动式雾化器防治闽北丘陵林区松毛虫和刚竹毒蛾。利用简易沙土临时机场，应用ＧＰＳ卫星导航仪定位近距离作业。作业航速１１０－１２０ｋｍ／ｈ，作业高度１０－２０ｍ，喷洒溴氰菊酯和白僵菌生物制剂的混合剂，取得较理想的防治效果。