Relationship between plant species diversity and patch characteristics in a marsh in the Sangjiang Plain, China —Using Yaluhe farm as an example

Based on Quick Bird satellite image data, the present study examined small-scale herbaceous community patches in the marsh of the Sanjiang Plain and measured patch characteristics such as the area, perimeter and shape by GPS. The coenological characteristics of the patches were investigated using quadrat method, and the vascular plant species were recorded using transect method. A total of 219 plant species were recorded, which represents 12.2% of the vascular flora in Heilongjiang Province. Our results showed that species number S correlated with patch area and perimeter; richness index (R) correlated with patch perimeter; Simpson index (D) correlated with patch area and perimeter/area; Shannon-Wiener index (H′) correlated with patch area, perimeter and perimeter/area; Evenness index (Jsw) correlated with perimeter/area. Both S and R have significant difference between different size of patches. Plant diversity in the small-scale herbaceous communities tended to increase with the patch area and perimeter. We concluded that edge effects and the habitat heterogeneity of the patches are important in determining the number of species. The relative smoothness of the patch edges also affects the plant diversity of the patches. The richness of plant species in the marsh in the Sanjiang Plain is highly sensitive to the small-scale patches, which continues to play an important role in preserving plant diversity in the local area.     

Relationship between plant species diversity and patch characteristics in a marsh in the Sangjiang Plain,China—Using Yaluhe farm as an example

Based on Quick Bird satellite image data, the present study examined small-scale herbaceous community patches in the marsh of the Sanjiang Plain and measured patch characteristics such as the area, perimeter and shape by GPS. The coenological characteristics of the patches were investigated using quadrat method, and the vascular plant species were recorded using transect method. A total of 219 plant species were recorded, which represents 12.2% of the vascular flora in Heilongjiang Province. Our results showed that species number S correlated with patch area and perimeter; richness index (R) correlated with patch perimeter; Simpson index (D) correlated with patch area and perimeter/area; Shannon-Wiener index (H′) correlated with patch area, perimeter and perimeter/area; Evenness index (Jsw) correlated with perimeter/area. Both S and R have significant difference between different size of patches. Plant diversity in the small-scale herbaceous communities tended to increase with the patch area and perimeter. We concluded that edge effects and the habitat heterogeneity of the patches are important in determining the number of species. The relative smoothness of the patch edges also affects the plant diversity of the patches. The richness of plant species in the marsh in the Sanjiang Plain is highly sensitive to the small-scale patches, which continues to play an important role in preserving plant diversity in the local area.     

轴对称问题中的无网格Galerkin法

采用无网格Galerkin法分析轴对称问题，得到弹性力学中的对称问题的无网格离散方程．将这一方法与有限元耦合，即在边界处布置有限单元，这样就可以用传统有限元方法方便地处理力学边界条件．算例考察表明：本文方法通过了分片检验，计算结果达到了较高的精度，最大误差不超过5％．     

三角分布下可追加订购的报童问题最优解

在经典报童问题中，订购是一次性的，这容易导致供货服务水平与无缺货风险贮存成本之间的矛盾。笔者研究可追加订购的报童问题，把收益作为目标函数，在追加订购数量有限制的条件下，建立了数学模型在假设需求满足三角分布下，讨论了最优解的具体求法。     

沙坡头地区人工-自然景观空间格局研究

研究人类活动对景观的影响是景观生态学研究的一个很重要的方面。人工－自然荒漠景观的空间结构受其沙漠背景的强烈影响，同时受强化了的人工干扰的影响，其格局带有明显的人为作用，对沙坡头地区荒漠景观生态空间格局基本特点、景观嵌块体类型及人类活动和自然的关系进行了分析，随着人类活动的加剧，景观多样性加大，均匀性、破碎度值和分离度值较大，为人活动已改变了荒漠局地的特性，生态恶化受到一定的遏止，但沙化影响正在威胁着人类对荒漠管理的成果，提出荒漠人工－自然景观研究中应注重景观生态风险及动态监测系统的研究。     

图像拓扑结构的识别及其应用技术研究

快速准确地建立两图像拓扑结构之间的对应关系是要解决的核心问题。通过揭示拓扑结构的本质特性,提出了邻接矩阵模型、局部模型和快速模型三种不同的拓扑结构的识别模型、数据结构及其算法,重点讨论了快速模型,并对其优良性能进行了证明。最后,把快速模型运用于全景图拼接,取得了令人满意的实验结果。     

景观生态学视角的城市绿地系统研究--以常州市新北区为例

从景观生态学的角度对城市绿地系统进行研究，充分考虑到绿地系统的景观和生态两种效应，对其做出科学的评价，并能指导绿地系统空间布局．以常州市新北区为例，利用景观生态学的理论，首先分析评价了新北区的绿地现状，进而提出了本区域的绿地系统的空间布局结构．借用景观生态学中的尺度原理，将整个新北区分成“区域宏观尺度、分区中观尺度以及具体规划设计的微观尺度”这3个尺度层次，并且对每个尺度层次利用景观生态学中相关原理分别进行研究，最终形成层次分明、在功能上相互补充、有机联系的绿地系统结构．     

适用于膜片钳技术的细胞分离及培养技术的研究进展

生物细胞膜片钳技术自八十年代问世以来,已经在电生理领域得到了很大的发展,但由于细胞分离及培养技术的原因,时至今日此项技术手段仍未普及。本文综述了膜片钳技术和组织培养,主要内容包括钳技术,组织培养的历史发展以及适用于膜片钳技术的神经细胞,心肌细胞,骨骼肌细胞等的分离培养方面的进展及前景展望。     

GPX3参与了H2O2对保卫细胞质膜钾通道的调控

通过表皮条生物分析、失水率测定及膜片钳实验研究谷氨酸过氧化物酶3(GPX3)能够调节保卫细胞质膜钾通道活性,并因此来介导H2O2诱导的拟南芥气孔关闭过程.与野生型Col-0相比,gpx3缺失突变在气孔开度和细胞失水方面均有较大差异.全细胞膜片钳模式下,1mmol/L的H2O2处理使野生型保卫细胞质膜钾离子通道外向电流从50pA左右激增到240pA左右,而gpx3的电流则变化不大.单通道电流的进一步分析表明gpx3不能像野生型一样对1mmol/L的H2O2处理产生明显反应,野生型与突变体的单通道电流差距高达10倍以上.据此推断GPX3是通过特异地调节外向钾通道来介导H2O2的信号传递.     

改进高校党校入党积极分子培训工作的思考

随着大学生入党积极分子人数的急剧增加，如何对高校拟列入发展计划的入党积极分子进行系统而有效的培训，是高校党校面临的一项重要课题。在分析高校党校入党积极分子培训工作中存在的问题的基础上，从提高认识、设立二级分党校、改革教学内容与形式、强化师资队伍建设、建立严格的管理机制等五个方面提出相关对策和建议。