Trunk-Top Relations in a Siberian Pine Forest

In this paper we study relations between trunks and tops of pines in natural Siberian forests. By statistical methods we show that the tops tend to deviate in the direction away from the nearest neighbour tree or from a summary of the trees in a given neighbourhood. In an alternative approach we show that the tops deviate into the direction of the empty space near the trunk position defined by the corresponding Voronoi polygon.     

Taking another look with fluorescence microscopy: Image processing techniques in Langmuir monolayers for the twenty-first century

Fluorescence microscopy has become a powerful and standard complementary technique in the study of amphiphilic films at the air-water interface. For nearly three decades the coupling of traditional thermodynamic measurements with direct visualization has provided a better understanding of self-assembled Langmuir monolayers and their application in the study of the physical properties of membranes and interfaces. As an introduction we provide a brief overview of this established technique and demonstrate its continued utility in the recent observation of novel phase behavior in monolayers of 25-hydroxycholesterol (25-OH) and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC). We then focus our review on new analysis techniques which take advantage of the ability to store, process, and analyze large sets of images. We pay particular attention to efforts measuring the line tension between coexisting two dimensional fluid phases in the Langmuir monolayer. Using non-perturbative methods, we can measure fundamental mechanical properties of these two dimensional systems. Finally, we highlight the use of Model Convolution Microscopy as a new tool to provide insight on the experimental limits in these studies.     

野生杜鹃花迁地保护适应性评价

通过半定量评价法 ,对四川都江堰中国杜鹃园内引种的来自各地的、分属杜鹃属 7亚属、 35组 (或亚组 )的 131种杜鹃花的适应能力和对各生态因子的耐性进行了研究。结果表明 :很适应的占 2 5 % ,适应的占 5 2 % ,欠适应的占 15 % ,不适应的占 8%。常绿杜鹃亚属、杜鹃亚属的多数种类或主要分布于常绿阔叶林、常绿落叶阔叶混交林、针阔混交林、寒温性针叶林中的杜鹃类群 ,很适应或适应中国杜鹃园的生境 ;而主要分布于高山灌丛、高山草甸上和低海拔松 -栎林中的杜鹃类群 ,表现为欠适应或不适应当地的生境条件。从上述证据中我们认为中国杜鹃园地址的选择基本上满足了杜鹃花的迁地保护需要。     

关于使用样线法估计种群密度

样线法是在大范围内估计野生动物种群密度的优良方法这一。我们在本文中说明了使用以平均垂直距离作为有效样带宽度来计算种群密度的简单数学公式一般不会得到可靠的效果。即使野外实施方式正确,使用该数学计算式估计出的密度结果也往往过于偏高。因此,我们建议最好合作计算机软件DISTANCE调查野生动物种群密度,并能熟悉样线距离取样法的理论基础。     

石山稀有濒危植物迁地保护适应性研究(简报)

报道了青檀、桂林紫薇、东京桐、掌叶木、任木、小花异裂菊和海南椴 7种石山稀有濒危植物迁移到酸性红壤上的表现     

The brain 5-HT4 receptor binding is down-regulated in the Flinders Sensitive Line depression model and in response to paroxetine administration

The 5-hydroxytryptamine (5-HT₄) receptor may be implicated in depression and is a new potential target for antidepressant treatment. We have investigated the brain 5-HT₄ receptor [³H]SB207145 binding in the Flinders Sensitive Line rat depression model by quantitative receptor autoradiography, and related this to 5-HT transporter ( S )-[ N -methyl-³H]citalopram binding. We also determined the regulation of 5-HT₄ receptor binding by 1, 14, and 21 days of paroxetine administration and subchronic 5-HT depletion, and compared this with changes in 5-HT_2A receptor [³H]MDL100907 binding. In the Flinders Sensitive Line, the 5-HT₄ receptor and 5-HT transporter binding were decreased in the dorsal and ventral hippocampus, and the changes in binding were directly correlated within the dorsal hippocampus. Chronic but not acute paroxetine administration caused a 16–47% down-regulation of 5-HT₄ receptor binding in all regions evaluated including the basal ganglia and hippocampus, while 5-HT depletion increased the 5-HT₄ receptor binding in the dorsal hippocampus, hypothalamus, and lateral globus pallidus. In comparison, the 5-HT_2A receptor binding was decreased in the frontal and cingulate cortices after chronic paroxetine administration, and markedly reduced in several regions after 5-HT depletion. Thus, the 5-HT₄ receptor binding was decreased in the Flinders Sensitive Line depression model and in response to chronic paroxetine administration.     

生态脆弱性及其研究进展

生态脆弱性已成为当前全球变化与可持续发展研究中的热点问题.有关生态脆弱性的研究,正逐渐从重点考察某单一生态要素发展到关注区域人地系统的整体性响应.当前生态脆弱性研究的内容主要包括系统变化分析、系统自身的敏感性与外部扰动的潜在影响,人地系统的适应性等.主要的研究方法有情景分析法、生态模拟法和指标评价法.目前生态脆弱性研究中存在的问题主要是情景分析与模拟的不确定性、适应性能力与社会经济发展的关系不明晰、自然因素与社会经济因素脆弱性研究相对不足等.生态脆弱性未来研究的重点是推进脆弱性研究多学科、跨尺度的融合,加强脆弱性中自然与人文因素的厘定和耦合研究,并开展基于历史变化史实的生态脆弱性实证分析.而作为脆弱性研究归宿,适应性研究不仅需要探讨能力建设和策略优化,还应深入研究适应性能力阈值与社会经济发展的关系以及国家、区域和群体之间适应性能力的总体协调与管理.最后,需要加强人地系统对极端自然灾害事件的脆弱性的研究.     

贺兰山东麓酿酒葡萄的生态适应性

从抗寒性、光合特性、生长及其结果性状等方面研究了宁夏贺兰山东麓酿酒葡萄的生态适应性。室内抗寒性鉴定和田间抗寒评价结果表明：‘歌海娜’最不耐寒,抗寒性强的品种有‘长相思’、‘雷司令’、‘黑比诺’、‘佳美,;抗寒力较差的品种有‘赛美容’、‘白诗南’、‘白玉霓’、‘神索’;抗寒力较强的品种是：‘霞多丽’、‘赤霞珠,、‘梅鹿辄’、‘白比诺’、‘西拉’。对酿酒葡萄的光合特性的测定发现：同一立地不同品种的净光合速率（Pn）差异明显,‘赤霞珠’的光合速率远高于‘霞多丽’、‘梅鹿辄’的,各品种光合速率的日变化呈双“S”曲线;全天光合速率的最高峰出现在上午10：00左右,下午14：00出现光合低谷,次高峰出现在下午17：00左右。同一品种在不同立地上的叶面积（LA）、叶鲜重（LFW）、比叶重（SLW）、叶绿素（Ch1）含量均表现差异;不同品种在同一立地条件下以上几个指标也表现不同。酿酒葡萄在贺兰山东麓不同区域的生长结果表现也不同。研究表明：大多数酿酒葡萄品种在贺兰山东麓具有良好的生态适应性,土壤和品种是造成贺兰山东麓酿酒葡萄生态适应性差异的主要因素,该区酿酒葡萄栽培的首要任务是解决抗寒栽培技术和土壤培肥。     

沙生灌木沙漠葳区域栽培试验

在吐鲁番、敦煌、民勤和天水4个地区进行了连续4年的沙漠葳[Chilopsis linearis（Cav．）Sweet]引种栽培试验,结果表明：沙漠葳是嗜热喜光的阳性树种,在吐鲁番生长表现良好,苗高、地茎、冠幅、主根长及侧根数等指标远高于其他试验区,苗高的年平均生长量可达2．26m,是其他3个试验区的3倍以上,2年生苗即可正常开花结实;在敦煌和民勤地区,沙漠葳能开花但种子不能成熟,植株生长量小,且受冬季低温和初春大气干旱的危害严重;在天水地区沙漠葳生长表现较好并能越冬存活,但不能正常开花结实。沙漠蒇的营养生长与年均温度和≥10℃有效积温呈显著正相关,相关系数分别达0．9868和0．9921,而与日照时数和相对湿度的相关性不显著。