NrDNA internal transcribed spacer revealed molecular diversity in strains of red seaweed <Emphasis Type="Italic">Porphyra yezoensis</Emphasis> and genetic insights for commercial breeding

Unraveling the cryptic genetic diversity and selective breeding network in various Porphyra strains is of significance for conservation and utilization of economically important nori crops, for both current and future needs. Here, we used nuclear ribosomal spacer (ITS1) region to investigate the genetic variation and intra-specific relatedness of 59 Porphyra yezoensis Ueda specimens worldwide using phylogenetic and parsimony genealogical approaches. 23 nrDNA ITS1 genotypes were revealed and clustering analysis grouped them into two distinct clades. High genetic diversity was detected in wild P. yezoensis strains from Miyagi and Hokkaido Prefectures in Japan, while the cultivated strains from China and South Korea exhibited relatively higher genetic diversity likewise, which provided crucial genetic insights for future commercial breeding of P. yezoensis on a global scale. In addition, phylogenetic study has revealed the genetic relationship of strains with unknown parentage to those with known parentage, and also ITS1 sequence pattern could be correlated with the geographic origin of P. yezoensis specimens. All these pedigree information generated from this research can be used to select parents for inter-specific or intra-specific selective breeding and cross breeding to maximize the preservation of stock resource and sustainable development of nori industry.     

课程改革中需要什么样的教师角色

课程改革毫无疑问需要教师的支持与参与，教师要以什么样的形象参与到课程变革中来？对这个问题的回答决定于课程改革中的教师观，同时也取决于教师专业发展的取向。在中国的课程改革语境下，需要大刀阅斧地改变以往课程变革中无效和无语的教师角色，让教师真正地实现主体意识的自觉，成为课程变革的审议者和教学与课程的研究者。     

青岛市草地资源现状及开发利用对策

详细地综述了青岛市草地资源现状，分析了开发利用的有利条件和草地畜牧业发展趋势，提出了草地开发利用对策。     

高校节能型的水电管理之我见

节能是我国经济和社会发展的一项长远战略方针，也是当前一项极为紧迫的任务，随着社会各项事业的长足发展，水、电、气、地等各种资源、能源消费需求与供给的矛盾日趋突出。节能型高校是宏观政府运用科学发展观，建立和谐社会在高校领域的一个长远规划，它需要从整体上建立高等学校校园运行节能监管体系。     

杨树氮肥适宜用量试验研究

采用田间小区试验,在施用一定量磷钾的基础上,研究不同氮用量对江汉平原杨树的生长及材积量的影响。研究表明:杨树每株施用纯氮100g,材积量每hm~2比对照多增2.84m~3,增产率66.98％,差异达极显著水平;每株杨树施用氮素100g比施用氮素50g,材积量每hm~2多增1.16m~3,多增产19.59％;株施氮素100g比不施用氪素每hm~2净增收入624元,投产比1.00:2.74。综合分析,江汉平原杨树每株施用氮素100g为宜。     

云南金沙江流域华山松人工林水土保持效益研究

以裸地为对照 ,对云南金沙江流域的华山松人工林林地的土壤物理性状及营养成分、林分涵养水源的能力、林冠层降雨截流功能、土壤水分动态变化、土壤渗透能力、林地地表径流及泥沙量以及地表生物量和根系分布状况进行了定点、定量观测研究。结果表明 :华山松林对改良土壤、增加肥力具有明显的作用 ,与裸地相比 ,其林地有机质、土壤月均含水率、渗透性能分别是裸地的 2 74、 1 14、 4 6 1倍 ,土壤最大蓄水量比裸地高5 6 74 % ;华山松林分年降雨截流量为 6 3 7mm ,截流率为 2 0 2 % ,径流率为 5 7%。径流削减率为 91 3% ,泥沙削减率为 95 6 % ;土层 2 0cm之上根系占总量的 83% ,对地面固土保水起着重要的作用     

黑银杏优良无性系选育研究

在对全县银杏种质资源普查的基础上，通过初选、复选和高接栽培对比试验，从２９７株雌银杏古树中发现并选育出了两个具有药用价值高、结实早、丰产稳产、抗逆性强等特点的黑银杏优良无性系———中银黑１号和中银黑２号。黑银杏种仁中总黄酮含量０９ｍｇ／ｋｇ，叶片中总黄酮含量８５ｇ／ｋｇ，分别比普通银杏高５０％和４１７％。文中还介绍了黑银杏的优良经济性状、生物学特性和生态学特性。     

FORESTAR：A decision—support system for multi—objective forest management in Northeast China

Past monoculture forestry in China has contributed to countrywide ecological disasters and economic difficulties in forestry regions. China‘s new forestry programs, Natural Forest Conservation Program and Returning Farmlands to Forests Program, provide opportunities for ecosystem management of mountain forests in China. A decision support system, FORE-STAR, has been developed for better managing and protecting natural forests in Changbai Mountain area. It uses GIS-based forest inventory data at a scale of forestry bureau. The first version contains two sub-modules: forest operation and forest res-toration. Under each sub-module, users can compare several decision options and make optimal choices. It can help field for-esters, forest managers, and policy makers make multi-objective and consistent decisions in planning forest management at hierarchical administrative scales.     

秦皇岛市区园林昆虫种类调查初报

本文作者利用2年时间,对秦皇岛市区园林昆虫区系进行了调查。初步摸清了秦皇岛市区园林害虫种类及天敌昆虫资源情况。共查出园林害虫50科235种,园林天敌昆虫10科22种。为科研、教学及生产提供了依据。     

草炭容器育苗试验

草炭容器 ,是有别于其它种类容器的一种育苗容器 ,是一种无公害容器。采用该种容器培育苗木 ,苗木发芽率高、生长健壮 ,无病虫害。造林时无须撕掉容器 ,成活率高 ,没有缓苗期 ,经过几年的观察 ,长势很好 ,本种容器可适于干旱、半干旱地区和石质山区育苗、造林 ,也可广泛应用于农业、蔬菜、花卉等领域育苗