巴音布鲁克亚高山草原生态系统CO2源/汇关系初步研究

利用光合作用仪,在牧草生长量最大的7,8月份,对围栏封育条件下亚高山草原CO2的源汇关系进行了初步研究,围栏封育条件下,CO2净固定量为19.65 g/m2.d;而自然放牧条件下则为19.24 g/m2.d,表明自然放牧条件下,草地植被对CO2的固定能力稍弱;从源汇关系日变化来看,围栏封育下,16:00以前是明显的碳的强汇,占到日总CO2净固定量的85.60%;自然放牧条件下,出现了4个弱汇,即9:00,13:00,14:00和21:00,其中15:00~20:00对CO2固定量占到日固定量的70.17%。围栏封育条件下草地植被对CO2的固定呈现先强后弱的趋势,而自然放牧条件下则相反。     

南水北调中线水源区生态旅游开发模式研究

分析了南水北调水源区生态旅游资源的特征,评估了该区生态旅游资源的开发条件,提出了生态旅游资源开发的设想,设计了6种生态旅游开发模式和3类旅游产品,并讨论了南水北调水源区生态旅游资源的开发重点和次序。     

南京玄武湖污染源调查与分析

结合近年的调查数据,分析了玄武湖可能存在的外源和内源污染。结果表明,入湖沟渠污染是玄武湖的主要外源污染,也是加重湖泊内源污染的诱发因素。因此,控制外源污染,改进截流措施,保证入湖水水质对今后的治理工作有很大的意义。     

农业非点源污染状况与防治(综述)

综述了农业非点源污染现状、主要污染途径与为害以及防治策略,并就我国农业非点源污染的研究与防控做了初步展望.     

不同饲料蛋白源对仿刺参幼参生长的影响

在水温12.0～19.5℃条件下,分别以玉米蛋白、大豆蛋白、鱼粉、虾粉和豆粕作蛋白源,添加海泥、鸡粪、马尾藻、贝壳粉、复合矿物盐和维生素,配制成等蛋白(25.0%)和等脂肪(5.0%)饲料,喂养平均体质量4.69g的仿刺参。60d的饲养试验表明,摄食不同试验饲料的仿刺参的特殊生长率由高至低依次为:鱼粉组>虾粉组>玉米蛋白组>大豆蛋白组>豆粕组,但差异不显著(P>0.05)。摄食玉米蛋白的仿刺参对粗蛋白的消化率最高(66.49%),鱼粉组的消化率最低(21.09%);摄食豆粕的仿刺参对粗脂肪的消化率最高(46.07%),鱼粉组最低(25.16%);摄食玉米蛋白的仿刺参体内粗蛋白含量最高,对饱和、不饱和脂肪酸的吸收利用率均最高,投喂植物性为主的饲料时仿刺参的营养价值较高。     

香菇菌丝的液体发酵碳源与多糖产量研究

[目的]研究香菇菌丝液体发酵碳源对香菇多糖产量的影响。[方法]以葡萄糖、淀粉和蔗糖作碳源,苯酚-硫酸法测定多糖,柱层析分离多糖,采用正交设计法对香菇真菌发酵的碳源进行研究。[结果]香菇真菌发酵生产香菇多糖的最佳碳源为6%葡萄糖,4%淀粉,2%蔗糖。淀粉对香菇多糖的产量有显著影响。对比试验发现,添加淀粉作碳源有利于香菇菌丝生长发育和多糖的积累。葡萄糖浓度与吸光度A490nm间存在极显著的线性关系。红外光谱分析显示,香菇菌丝发酵获得的香菇多糖为吡喃型的β-D-葡聚糖,纯化后与由子实体获得的香菇多糖没有本质的不同,但产量不高。[结论]香菇菌丝在富营养化条件下可以积累香菇多糖。该研究对香菇多糖的发酵生产具有一定的指导意义。     

兼抗黄瓜枯萎病、角斑病和黑星病育种材料苗期筛选

通过苗期复合接种法对44份黄瓜高代自交系材料进行枯萎病、角斑病和黑星病多抗抗源鉴定、筛选。接种鉴定结果表明,44份材料对枯萎病均表现为高抗或抗病;14份材料抗角斑病,2份表现感病,其余均为中抗类型;只有2份材料抗黑星病,其余均为高度感病或感病。同时兼抗3种病害的材料只有1份,占2.3%;兼抗枯萎病和角斑病的材料15份,占34.1%,兼抗枯萎病和黑星病的材料只有2份,占4.6%。     

一种绿色环保能源-生物柴油

生物柴油作为一种绿色的可再生能源,可以由动植物油脂通过酯交换反应来制备.本文概述了近年来国内外生物柴油的发展现状、生物柴油的特性、生物柴油的环境效益及社会经济效益和发展生物柴油的建议及展望.     

Yield, Leaf Senescence, and Cry 1 Ac Expression in Response to Removal of Early Fruiting Branches in Transgenic Bt Cotton

Two-year field experiments were conducted at Linqing, Yellow River valley of China, to study the plant response to the removal of early fruiting branches in transgenic Bt (Bacillus thuringiensis) cotton (Gossypium hirsutum L.) from 2003 to 2004. Plants were undamaged and treated by removing two basal fruiting branches (FB) at squaring to form the control and the removal treatment, respectively. The plant height, leaf area (LA), dry weight of fruiting forms (DWFF), the number of fruiting nodes (NFN), photosynthetic (Pn) rate, and levels of leaf chlorophyll (Chl), N, P, K, and Cry 1 Ac protein in mainstem leaves were measured at a 10-or 20-d interval after FB removal, and the sink/source ratio as indicated by NFN/LA and DWFF/LA was determined. FB removal significantly increased the plant height, LA, and plant biomass in both years. Lint yields were increased 7.5 and 5.2% by removal compared with their controls in 2003 and 2004, respectively. Significant increases in boll size (5.7 and 5.1%) were also observed in removal than in control for both years. Either NFN/LA or DWFF/LA was significantly reduced by removal before 40d after removal; however, both NFN/LA and DWFF/LA were significantly enhanced by FB removal at 80d after removal compared to the untreated control. There was no significant difference in fiber quality in the first two harvests between removal and control, but fiber strength and micronarie in the third harvest were significantly improved by FB removal. In terms of leaf Chi, Pn rate, levels of total N, P, and K in late season, leaf senescence was considerably delayed by FB removal. Levels of Cry 1 Ac protein in the fully expanded young leaves were considerably higher in FB-excised plants than in control, indicating FB removal enhanced Cry 1 Ac expression. It is suggested that the yield and quality improvement with FB removal may be attributed to the increased NFN/LA or DWFF/LA in late season and delayed leaf senescence, respectively. FB removal can be a potential practice incorporated into the intensive cultivation system for enhancing transgenic Bt cotton production.     

水源地水质安全评价指标体系研究

在阐述水源地水质安全定义的基础上,根据"压力-状态-响应"(PSR)模型和层次分析的思想,建立了一个适用于水源地水质安全的结构简单、层次分明的一般指标体系,并分析了该指标体系的特点。