水稻节水高产灌溉模式及土壤水分能量调控标准研究

根据土壤—植物—大气连续系统原理，1989～1998年在沈阳农业大学灌溉试验场通过盆载、蒸渗仪、小区及大田进行试验，分析了水稻的需要水规律及稻田土壤水分能量的变化特点，论述了土壤水分状况与水稻腾发强度之间的关系、不同灌模式对水稻腾发量的调控作用以及水分胁迫对水稻产量的影响，提出了水稻节水高产灌溉模式和土壤水分能量调控标准。     

浅议广东森林自然度划分标准

森林自然度反映现实森林类型与地带性原始顶板森林类型的差异程度。是反映森林质量和生态状况的一项重要指标。文章叙述了广东省森林自然度划分标准及实践应用情况。探讨了实践应用中存在的问题，提出了完善划分标准的建议。     

An Economic Investigation of Early-Generation Quality Testing in a Wheat Breeding Program

Public plant breeders, in seeking the most efficient means of achieving their objectives, face decisions on the appropriate breeding strategy and program structure to use. This paper reports an analysis comparing the changes in costs and benefits from the introduction of recent technology enabling testing for flour and dough properties to be carried out on small samples in the early-generations of a wheat breeding program in Australia. The average costs of a suite of early-generation tests are higher than the equivalent (unreplicated) yield testing. The analysis presented confirms that the introduction of early-generation quality testing leads to a faster rate of expected progress in quality, but a slower rate of progress in yield. The estimated market value of an increase in yield is greater than that for quality, based on current market information. Thus, the result of incorporating early-generation quality testing is higher costs and lower expected returns, so that there is a loss of community welfare from using early-generation quality testing if the resultant cultivar is released from each program. However, the probability of the higher-quality cultivar being released for commercial cultivation is greater, so that recognition of the probability of release means that there may be net gains from the use of early-generation quality testing.     

Comparison of production systems and selection criteria of Ankole cattle by breeders in Burundi, Rwanda, Tanzania and Uganda

A survey in Burundi, Rwanda, Tanzania and Uganda was conducted in order to determine the different production systems under which Ankole cattle are currently kept. Additionally, selection criteria of livestock keepers were documented. In Burundi, Rwanda and parts of Uganda, livestock keepers are sedentary and herds are small, whereas in the other areas Ankole cattle are kept in large herds, some of them still under a (semi-)nomadic system. Milk is the main product in all areas, and is partly for home consumption and partly for sale. Although the production systems vary in many aspects, the selection criteria for cows are similar. Productive traits such as milk yield, fertility and body size were ranked highly. For bulls, the trait ‘growth’ was ranked highly in all study areas. Phenotypic features (coat colour, horn shape and size) and ancestral information are more important in bulls than in cows. The only adaptive trait mentioned by livestock keepers was disease resistance. In areas of land scarcity (Burundi, Rwanda, western Uganda), a clear trend from pure Ankole cattle towards cross-bred animals can be observed.     

医疗网站信息服务质量评价标准

介绍了国内外医疗网站信息服务的评价方法和标准,阐述了目前互联网医疗网站信息服务的评价研究现状及发展趋势。     

Fuzzy Assessment Method for Seismic Damage of CFST Arch Bridges

In order to investigate the conditions of damage and failure of concrete-filled steel tube(CFST) arch bridges, considering the structural and mechanical characteristics of CFST arch bridges, the dual damage criteria assessment models of the various components based on deformation or strength and energy were developed. The nonlinear seismic response of CFST arch bridges was analyzed by finite element method and the fuzzy evaluation method of seismic damage based on fuzzy theory and analytic hierarchy process was studied. Finally, taking a long-span CFST arch bridge as example, the damage index of the bridge was 0.150, 0.152, 0.172 and 0.318 respectively when the seismic peak acceleration was respectively 0.1g, 0.2g, 0.4g and 0.8g. The results show that the CFST arch bridge is slightly damaged under the earthquake when the seismic peak acceleration is 0.4g, and the bridge is damaged moderately when the peak acceleration is 0.8g.     

六价铬对黄颡鱼仔鱼和稚鱼的急性毒性效应研究

利用静水式鱼类急性毒性测试法,分别以黄颡鱼（Pelteobagrus fulvidraco）仔鱼和稚鱼为受试对象,通过六价铬的急性毒性试验,获得24、48、72、96 h相应的半数致死浓度LC50值,比较了六价铬对黄颡鱼仔鱼和稚鱼的致毒敏感性,计算了六价铬对黄颡鱼的安全质量浓度并对六价铬对于黄颡鱼急性毒性等级进行了评价。旨在通过开展我国本土水生生物的急性毒性效应的研究,获得相应的毒理学数据,为推导符合我国生态分区特点的水质基准提供基础信息。结果表明,在水温为（23±2）℃条件下,六价铬对黄颡鱼仔鱼24、48、72、96 h的半数致死浓度LC50分别为28.32、21.99、17.70、15.79 mg.L-1,而对黄颡鱼稚鱼24、48、72、96 h的LC50分别为138.5、88.36、68.55、57.98 mg.L^-1,说明黄颡鱼仔鱼对于六价铬毒性的敏感性明显高于稚鱼。六价铬对黄颡鱼仔鱼和稚鱼的安全浓度分别为1.579、5.798 mg.L^-1,依据急性毒性结果和鱼类急性毒性分级标准,六价铬对于黄颡鱼毒性等级属于中等毒性。     

27个木槿品种的数量分类和主成分分析

通过观测27个木槿品种的17个数量和质量性状,探究了木槿品种分类的等级和标准,便于为木槿品种的选育与资源研究等提供参考依据。首先对17个性状指标进行R型聚类分析和主成分分析,根据分析结果再对27个木槿品种进行Q型聚类分析。R型聚类分析结果表明,各性状选取是合理的;主成分分析结果表明,17个性状可综合为6个主成分,其累计贡献率达88.096%。Q型聚类结果表明,27个木槿品种根据有无丹心、花型、丹心基部形状、花瓣指数、花径、叶形、丹心线与丹心的关系可被分为2大类、3大类或8大类。16个性状对木槿品种的划分贡献较大。综合而言,有无丹心、花型、花瓣指数、丹心线与丹心的关系是木槿品种分类的主要标准和依据。     

富士和嘎啦苹果叶片面积估算模型构建

【目的】建立准确、无损的适宜于苹果不同品种和枝梢类型的叶面积估算模型。【方法】以富士及嘎啦不同长度的营养枝梢和果台枝梢叶片为试材,采用数字扫描仪获取叶片长度(LL)、宽度(LW)和叶面积(LA)等叶片形态参数,并采用决定系数(R²)、均方根误差(RMSE)、赤池信息准则(AIC)对建立的17个有常数项和无常数项叶面积模型精度进行筛选和适宜性评价。【结果】共获得5 207枚叶片形态参数,其中叶面积变异系数最大,达51.59%。叶片形态受品种及枝梢类型的显著影响,其中长枝梢叶片长、宽和叶面积显著大于同类型短枝梢叶片,而营养枝梢叶片长、宽和叶面积显著大于同长度果台枝梢,嘎啦叶片相比富士更为细长。以LL和LW复合变量为自变量的模型5:LA=a(LL×LW)、模型6:LA=a(LL+LW)²、模型9:LA=aLL²+bLW²、模型16:LA=a(LL×LW)^b、模型17:LA=(LL×LW)^b的精度可满足富士和嘎啦各类枝梢叶面积的估算,但需针对各品种和枝梢类型单独建...     

Traditional leafy vegetables and their use in the Benin Republic

Seventy-three villages randomly selected in 29 ethnic areas and three regions or agro-ecological zones of Benin were investigated by a participatory rural appraisal survey to assess the diversity of the species used as traditional leafy vegetables (TLVs). In total, 187 plant species belonging to 141 genera and 52 families were recorded. Among these, 47 (25.13%) were cultivated and 140 (74.87%) were gathered from the wild. Herbs (64.78%) were the most numerous followed by shrubs (19.78%) and trees (15.50%). The Shannon–Weaver diversity index calculated was 3.232. The total number of TLVs used highly varies, across ethnic groups, from 15 (Toli tribe) to 58 (people Mahi) with, on average, 36 species per ethnic group. The relative proportions of the wild and cultivated species used also vary with the tribes but on average appeared almost the same. Of the species inventoried, 18 of national importance were found among which Solanum macrocarpon, Corchorus olitorius, Amaranthus cruentus and Gymnanthemum amygdalinum ranked first. The matrix scoring technique yielded 12 criteria of different natures used to define preference. Among these, four (taste, ease of preparation, availability and quantity of required condiments) were the most important and represent, all together, more than 72% of responses. Despite the diversity of species used as leafy vegetables, they were all basically consumed in the same way. Sauces were the main type of preparation and involved all the species. The perceived nutritional and medicinal (curative, regulative and stimulative) properties of the species as well as their cultural significance were documented. Some TLVs are known and consumed by all or many ethnic groups while many others were simply ethnospecific or used by only a few peoples. However, no correlation was found between the distribution of the utilisation of the species and their degree of consumption which all depend on the eating habits of the peoples. Cluster analysis revealed that peoples sharing a common geographical space and/or cultural identity or origin seem to consume almost the same types of TLVs and cluster together. Given the large quantity of evidence of the importance of the TLVs, there should be a systematic effort to improve their understanding and their uses to reduce if not alleviate rural poverty and malnutrition in Benin.