10 May 2007, Volume 25 Issue 0709

    

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天然草原管理研究专题
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  Advance of Technology of Remote Sensing Monitoring for Grassland Vegetation

  . 2007, 25(0709): 5-8.

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  The advance of technology of remote sensing monitoring for grassland vegetation in China, especially administered by the Ministry of Agriculture of China, is reviewed in this paper. Some key issues are discussed. It is suggested that priority fields should be focused on the precision and standardization. Information management platform of remote sensing monitoring of grassland will also play an important role and should be constructed.
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  Potential of Grassland Agriculture in Southern China and Its Significance to Food Security

  . 2007, 25(0709): 9-15.

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  Discussed in this article are major types of grassland agricultural systems in southern China and their potential productivities in the context of food security. The analysis indicates that southern China, with a favorable climate and diverse land forms, is of great potentiality for grassland agriculture development. Typical types of grassland agriculture in the region include cultivated perennial pastures on temperate uplands, annual ryegrass on winter-fallow paddyfields, integrated warm-cool season annual forage crops, and silvipastoral systems. With rapid economic growth, there has been a decrease in per capita consumption of food grain, but an increase in per capita consumption of meats, which offers a good opportunity for developing grassland agriculture. A simple calculation indicates that the forage production may substitute the grain production in some extent with respect to food consumption demands.
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  Ecological Issues and Improvement System for Rangeland in Arid and Semi-arid Area in Northern China

  . 2007, 25(0709): 16-21.

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  The grassland from arid area in northern China is the primary Rangeland, and also is the main area of original sand storm in China. The facing key limited facts for rangeland are introduced，which the relative information was collected from the national key program and the international program conducted in northern China. Ecological issues surrounding rangeland resources, water supply, grassland degradation and forage productivity are indented to be the most critical issues. As a demonstration sample，Xilingole grassland area is exhibited to sum up the technology system for vegetation recovery and grassland improvement. A series of strangers are suggested to improve grassland management and to increase the grassland management effect.
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  Classification and Development of Husbandary Counties and Semi-husbandary Counties in China

  . 2007, 25(0709): 21-25.

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  In this paper, a new classification scheme of husbandary counties and semi-husbandary counties is proposed, which concerns 111 husbandary counties and 168 semi-husbandary counties, based on the ratio of grassland areas to farmland areas and the ratio of husbandary product to agricultural product. The classification identifies also their industrial types, such as protection and construction type, capital construction type and ecological tourism type. It is concluded that both husbandary counties and semi-husbandary counties should adopt a sustainable development strategy based on the overall regional development.
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  Functions of Ecosystem in the Tibetan Grassland

  . 2007, 25(0709): 26-28.

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  The functions of ecosystem in Tibetan grassland include ecological functions, production functions and living functions. Maintenance and development of the Tibetan grassland ecosystem mainly depend on its intrinsic ecological functions. The production functions play as a key role in the improvement of Tibetan grassland ecosystem. A balance between ecological and productive functions determines the level of the living functions, which reflects the development state of the integrated Tibetan grassland ecosystem management. It is very important to understand fully the interactions among "three functions" for maintenance and development of the Tibetan grassland ecosystem.
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  Reform of the Household Responsibility System for Sustainable Development in Pasturing Area in Northern China

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  . 2007, 25(0709): 29-32.

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  There are some essential differences between cropland and rangeland. Cropland can often be seen as a private renewable resource, while rangeland is usually a public renewable resource, so since the Household Responsibility System in Pasturing area (HRSP) was put in force, the so-called "tragedy of commons" in pasturing area has become worsened. The HRSP should put into account of the difference between rangeland and cropland. The government should take over the main responsibility of property rights, exclusive from herders; the HRSP should involve the household only in benefit allocation, not in rangeland utilization, and should encourage cooperation among herders, instead of building so small ranches in rangeland; and autonomous management and regional management should be encouraged, with the HRSP serving as the foundation of collective actions among herders. So it is crucial to reform the HRSP for better rangeland management. This is important for a sustainable development in pasturing area.
Articles
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  Geometric Structures of Fisher Z Distribution

  . 2007, 25(0709): 33-36.

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  Fisher Z distribution is a widely used statistics distribution in practice. In this paper, the Fisher Z distribution is studied from the viewpoint of information geometry. A dual affine structure is constructed on it and a divergence is defined as a distance like measure. Furthermore, the Riemannian metric, ?琢-connections and ?琢-curvatures of the Fisher Z manifold are given. At last, an immersion from the Fisher Z distribution manifold into the affine space is obtained.
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  Determination of Nitroimidazoles Residue in Chicken Tissues

  . 2007, 25(0709): 36-39.

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  A new HPLC method for determining the Nitroimidazoles in chicken tissues is proposed, based on the studies on the method of pre-processing of tissues and by adjustments of the time and temperature of extraction, the mode of shaking and the dropping rate during cleaning. The results show that the recovery rate is increased from 40%～50% to 70%～80%. This method is easier to be implemented than the previous one and is an optimization of the method in the 236th bulletin of Ministry of Agriculture.
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  Study on the Influence of Plot Area Size on Estimation of Stand Density and Analysis of Patterns of Natural Forests

  . 2007, 25(0709): 40-46.

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  Data from 4 100 m×100 m natural forest plots were used to estimate tree number per hectare and basal area based on plot sizes, the difference between estimated and actual values was calculated. Then a uniform angle index and a pair-correlation function were used to analyze the spatial patterns of trees in forest plots with varying sizes. It is shown that both the spatial and non-spatial structure indices of forest are related to plot sizes. Both densities and patterns become stabilized with increasing plot sizes, indicating that stand densities and forest patterns should be estimated or analyzed with data from big enough plots. According to our study, 2 500 m2 is appropriate for either the estimation of stand densities or analysis of forest patterns.
Reviews
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  Progress in Gene Convertion Research: Molecular Mechanisms and the Application in the Process of nrDNA Concerted Evolution

  . 2007, 25(0709): 47-51.

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  Gene conversion is defined as a non-reciprocal transfer of information between homologous sequences and has been found in a wide variety of karyotic and eukaryotic organisms. It plays an important role in reversion, concerted evolution, antigenic variation, antibiotic resistance and gap repair. Molecular models, including Holliday model, Meselson-Radding model, DSBR model, and SDSA model, can be used to explain gene conversion. In this paper, these molecular mechanisms, as well as the role of gene conversion in the process of nrDNA concerted evolution we reviewed.
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  Spatial Information Technology-based Supporting System for the Development of Mining Industry and Mining Areas: Research Progress and Several Key Techniques

  . 2007, 25(0709): 52-59.

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  For sustainable development of mining industry and mining areas and using Spatial Information Technologies (SIT), the SIT-based supporting system for sustainable development is discussed from regional and industrial aspects. The applications of SIT to four key fields, including safe production and disaster prevention and mitigation, environmental protection and ecological treatment, optimal and intensive use of mineral resources, and Spatial Decision-making Support System (SDSS) for mining areas and mining industrial cities, are analyzed in detail with respect to their current situation and key techniques. Some key issues that should be researched in a near future are pinpointed, and they are integration of multi-sources and heterogeneous information, spatial data mining, spatio-temporal simulation of disaster and environmental processes, quantitative inversion of ecological and environmental parameters and the establishment of SDSS.
研究报告
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  Be Discreet in Quoting SCI

  . 2007, 25(0709): 60-64.

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  The SCI database has been widely used in China for more than a decade. In view of the special nature of its index methods and the recent development of this database, not all items indexed by SCI could be viewed as scientific research papers. Some may be conference papers. The Impact Factor( IF) is affected by many different factors,and is not perfect in representing the quality of the related paper. It's suggested that a discretion be exercised in the use of SCI in the scientific research evaluation system carried out by government departments and academic institutions in China.
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  Study on the Complexity of Enterprise Strategy and a Strategic Design Model

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  . 2007, 25(0709): 65-69.

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  This paper discusses the complex characters of an enterprise strategy system. It is shown that the chaos and fractal phenomena will appear in the system. The management strategies based on complexity science are proposed from such aspects as construction, implementation, control and reform, which may serve as guidelines for managers.
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  Development of Art-Agriculture——With Yangling Area as an Example

  . 2007, 25(0709): 70-73.

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  Artistic agriculture is a new agricultural industry, which combines agriculture and arts. Based on its definition, this paper makes an analysis of the characteristics and the classification of the artistic agriculture. According to a case study of Yangling Area, the feasibility and development strategies of the artistic agriculture development in Yangling Area are discussed.
科技评论
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  My Favorite Three Books

  . 2007, 25(0709): 74-75.

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  Reading is an important thing of one's growing, a man's spirit is based on his reading experience, and the nation's spirit based on the people's reading level. April 23 is the World Reading Day. To most of scientist, the knowledge of culture and literature is limited. Then, three books are introduced to readers: An Outline History of China, The Joy of Thinking, The Kitchen of Beitai.