Spatial distribution and abundance of small fishes in Xiaosihai Lake,a shallow lake along the Changjiang (Yangtze) River, China

Spatial distribution and abundance of small fishes were studied in autumn 2007 in the Xiaosihai Lake, a shallow lake along the middle reach of the Changjiang (Yangtze) River. Based on the plant cover, the lake was divided into three major habitats: Myriophyllum spicatum habitat (MS habitat), Trapa bispinosa habitat (TB habitat), and non-vegetation habitat (NV habitat). A modified pop-net was used for quantitative sampling of small fishes in the three habitats, and the Zippin’s removal method was used for estimating densities of the small fishes. A total of 13 species belonging to 5 families were collected, with 11 species in MS habitat, 7 species in TB habitat, and 5 species in NV habitat. Habitat type had significant effect on the spatial distribution of small fishes. The Shannon-Wiener diversity index in the MS, TB and NV habitats were 1.28, 0.56 and 0.54, respectively. The total density and biomass of small fishes were significantly higher in the MS habitat (13.68 ind/m2 and 4.44 g/m2) than in the TB habitat (1.41 ind/m2 and 0.54 g/m2) and the NV habitat (1.08 ind/m2 and 0.40 g/m2), and were not significantly different between the TB habitat and the NV habitat. Water depth had no significant effect on spatial distribution of the small fishes. It was suggested that vegetation type played an important role in habitat selectivity of small fishes, and the presence of submersed vegetation should be of significance in the conservation of small fish diversity

洪泽湖大型底栖动物群落结构及其与环境因子的关系

洪泽湖是我国第四大淡水湖,然而关于洪泽湖大型底栖动物的报道较少。为了研究洪泽湖大型底栖动物群落结构特征及其影响因子,在洪泽湖设置20个采样点,进行了为期1周年的季度调查(2010年5月-2011年2月)。共采集到大型底栖动物14种,寡毛类、摇蚊科幼虫和软体动物分别有5种(占总物种数的35.7%)、3种(21.4%)和6种(42.9%)。河蚬为第一优势种(优势度Y=0.18),其次分别为苏氏尾鳃蚓(0.09)、羽摇蚊(0.07)、霍甫水丝蚓(0.06)和铜锈环棱螺(0.06)。群落的平均密度和平均生物量分别为(45.45±7.38)个/m2和(52.43±12.04)g/m2,其中软体动物平均密度和平均生物量最高[(24.80±6.20)个/m2和(49.55±11.94)g/m2],摇蚊类次之[(13.76±2.87)个/m2和(2.28±0.71)g/m2],寡毛类最低[(6.96±2.41)个/m2和(0.60±0.18)g/m2]。全湖Shannon-Wiener、Margalef和Pielou指数分别为2.69、1.10和0.71,各指数季节差异不明显。冗余分析(RDA)结果共解释物种数据累计方差的35.0%;MonteCarlo检验表明,洪泽湖水体中硝酸盐氮、总氮和化学耗氧量是影响底栖动物群落分布最关键的环境因子(F=2.181～3.277,P<0.05)

water resource allocation for the Songhua River Region, China under the uncertainty of water supply

<span class="MedBlackText">Water resources allocation (WRA) is a useful and yet complicated topic in water resources management. The solution of WRA may be uncertain due to the uncertainty of the input, the structure itself, and the parameters of the models. So far, very few studies deal with the topic about how much these uncertainties influence the solution and how to adapt the situation. By using Dependent-Chance Goal Programming (DCGP), this paper built a WRA under the uncertainty of water supply for the Songhua River Region (SHRR) located in the northeast of China, one of China's most important commercial grain bases. Two sets of WRA results were obtained under the two ranges of uncertainty relative to bad (S1) and good (S2) water supply situations. Situation SI takes a higher water shortage rate and S2 takes a lower water shortage rate than the routine WRA results by the SHRR Commission's comprehensive plan, but all keeping the rate of water resources exploitation approaching or lower than the international standards. The result helps SHRR to make a more resilient decision to the change of water supply condition in meeting the national needs of Newly Increasing Yield of 10 &times; 10¹¹ Jin. </span

新兴古典经济学与我国的税收征管改革

本文从新兴古典经济学的角度对我国的税收征管改革进行了分析,认为税收征管改革的实质就是分工专业化经济的好处与交易费用的权衡比较问题;税收征管改革的目标就是实现分工专业化经济的好处最大化,同时最大限度地减少交易费用

The Impact of Educational Attainment on Homeownership Evidence from China Family Panel Studies

住房问题和教育问题是重大的民生问题，也是社会关注的热点问题。房地产市场的快速发展，结合义务教育阶段“按片划分、就近入学”入学政策的实行并不断强化，刺激了学区房的畸形发展。学区房价格不断攀高，引来社会的广泛关注。为了孩子教育去购买住房甚至是学区房，是一般性的普遍行为，还是专属于富人的金钱比拼游戏。本文采用2008年中国家庭经济调查数据（ChinaFamilyPanelStudies,CFPS），研究在北京、上海和广东，有孩子的家庭为了孩子的教育是否有更强烈的动机去购买住房。Probit回归结果表明，总体而言，是否有孩子与是否拥有住房之间不存在显著的关系。考虑到北京、上海和广东这些地区之间在社会经...Housing problem and children’s education are not only major livelihood issues, but also hot issues of social concern. The rapid development of real estate market, combined with admission policy in compulsory education, stimulates the abnormal development of the school district room. School district housing prices have constantly raised, which attracted widespread attention. In order to enter prima...学位：经济学硕士院系专业：王亚南经济研究院_金融学(含保险学)学号：2772011115270

中国国际货物销售合同形式的法律适用

一、中国国际货物销售合同形式的概念就“国际货物销售合同的形式“而言,只能从“合同形式“的狭义上来理解。为本文研究之目的,“中国国际货物销售合同

德国税务诉讼举证责任分配的规则及借鉴

德国税务诉讼采用规范说确定举证责任分配的基本原则,但在税法和财政法院实务中并不拘泥于此,而是按个案以及税法规定的目的,基于与课税要件事实证据的距离对举证责任分配的基本原则予以修正,举证责任在纳税人与税务机关之间分配比较合理,这对完善我国的税务诉讼举证责任制度有积极的借鉴意义

Based on business process reengineering Xiamen Court information system research

随着中国经济的飞速发展，经济发展的不平衡性和市场规则的不完备，利益冲突的加大和社会防范解决机制的滞后，使得大量诉讼涌向厦门法院。这就使得厦门法院必须加强信息化建设，增进资源共享，提高信息的传递速度，节约诉讼资源，方便群众诉讼。更重要的是通过科技网络的信息化手段，为法院的审判管理提供强有力的技术支持，推动法院实现传统管理向现代管理的转变。 本文从诺兰（Nolan，R.L）模型、米歇（Mische）模型的信息系统发展阶段理论，分析说明了厦门法院的信息化发展各个阶段的情况，以便更好地指导厦门法院的信息化建设。 本文通过著名管理学家迈克尔&#8226;哈默（MichaelHammer）的流程再造理...Along with the Chinese economy rapid development, the economical development imbalance and the market rule are incomplete, the conflicts of interest enlarge and the society guard against the solution mechanism the lag, causes the massive lawsuits to rush Xiamen Court. This causes Xiamen Court to have to strengthen the informationization construction, promotes resources sharing, enhances the inform...学位：管理学硕士院系专业：管理学院工商管理教育中心（MBA中心）_工商管理硕士(MBA)学号：X200615507

A Study on the Options and Design of Tax Administration Mode Based on the Underdeveloped Market Economy in China

我国从1997年开始在全国推行“以申报纳税和优质服务为基础，以计算机网络为依托，集中征收、重点稽查”的新的税收征管模式，这一模式体现了以纳税申报、自核自缴为基础，以计算机网络为依托，适应于西方国家发达的市场经济环境，适应于以个人所得税为主体的税制结构。实践证明，新的征管模式实施以来，由于过于强调模式的集中统一，盲目追求税收征管形式上的现代化、表面上的先进性，税收征管模式远未涉及征管改革所要达到的目标，即用尽量低的征收成本和纳税人奉行成本，使税法的字面规定与其实际运行结果尽可能一致。为什么在西方发达国家运行良好的税收征管模式，在我国实施的效果并不理想呢？本文从我国不发达市场经济环境、不发达市场经...The current tax administration mode, which was based on self-assessment and taxation service, which was depended on computer networks and which centralize the collection and stress auditing, was performed in our country from 1997. This mode is suitable to the developed market economy environment and tax system based on personal income tax. From the practice, the current tax administration mode ...学位：经济学博士院系专业：经济学院财政金融系_财政学(含税收学)学号：B20034103