Winter losses of nitrogen and phosphorus from Italian ryegrass, meadow fescue and white clover in a northern temperate climate

We have studied to what degree Italian ryegrass (Lolium multiflorum Lam.), white clover (Trifolium repens L.) and meadow fescue (Festuca pratensis L.) are able to preserve nitrogen (N) and phosphorous (P) in shoots and roots from one growing season to the next in a northern temperate climate. Field experiments were performed during four consecutive winters in central southeast Norway (60°42′N, 10°51′E), and N and P in plant biomass were measured in the autumn and in the spring. We also measured the contents of total N, total P and organic carbon (C) in seepage water that percolated through the aboveground plant material. Uptake of N and P in Italian ryegrass and white clover was substantially larger than in meadow fescue. The winter losses varied greatly from year to year, depending on the winter climate. On the average for all three of the plant species, the winter losses of N from aboveground biomass were 6, 35, 68 and 10% in the four experimental years, respectively. The corresponding P losses were 11, 36, 60 and 22%. On the average for all plant species and experimental years, 43 (±12)% (S.E., n = 12) of the N, 34 (±9)% of the P and 4 (±1)% of the C that was lost from the aboveground plant biomass during the winter, was recovered in seepage water, basically as a nutrient pulse in melt water in early spring. The very low C recovery rate in seepage water suggested a considerable microbial growth on lost plant C. Assuming that all un-recovered plant C was consumed by microorganisms not included in measurements of the seepage water, modelling showed that microbial immobilisation theoretically might explain the unexpectedly low recovery rates of N and P. The study was not designed to investigate the possible effects of psychrophilic microbes on N and P cycling. Therefore, it is inconclusive and underlines the need for more knowledge on this matter.     

环境(非关税)贸易壁垒判析及其对策探讨

ＷＴＯ中有关环境的，国际环境公约、ＩＳＯ１４０００、等有关条款，本身并非绿色贸易壁垒，基于此，分析了绿色贸易壁垒的起因特征，对其相模糊的条款与规定，有可能成为绿色贸易壁垒的误区作了判析，提出了绿色贸易壁垒的５种形式：环境税、市场准入、环境技术标准、环境标志和贸易制裁，以及我国的对策思路。     

绿色食品(蔬菜)基地中Hg的调控机理研究

通过野外调查与盆栽试验相结合,探讨配合施用石灰、腐殖酸和膨润土3种抑制剂对降低莴笋可食部分Hg含量的最佳效果.研究结果表明:配合施用腐殖酸、膨润土及石灰修复受Hg污染的土壤,既可保证作物不减产,又能大幅度降低蔬菜可食部分Hg含量.     

原油贮罐工程施工中的安全用电应对措施

针对原油贮罐工程施工中的用电问题,提出改进安全用电的应对措施.     

绿色水处理剂的研究与应用进展

绿色水处理剂是水资源保护的重要环境材料,在水环境治理中发挥着重要作用,是环境工程的重要研究领域。介绍了绿色水处理剂的概念,回顾了绿色絮凝剂、缓蚀阻垢剂、杀生剂及多功能水处理剂的发展与应用,最后展望了绿色水处理剂的发展趋势。     

环境（非关税）贸易壁垒的发展趋势与我国企业的对策

根据国际贸易中的绿争贸易争端分析了绿色贸易壁垒的发展趋势。我国即将加入WTO，作者基于这一现实提出了我国企业在加入WTO后冲破绿色壁垒的七点对策。     

产品生命周期工程中废弃物控制与治理研究

介绍产品生命周期工程的内涵，探讨如何从整个产品生命周期分析研究入手，采用绿色设计的手段，使废弃物减量化，资源化，从而使废弃物对环境产生的负影响最小，以实现人类可持续发展。     

油品储运过程中的静电危险性分析及防范措施

对油品储运过程中存在静电危险性的原因进行了分析,提出了相应的防范措施.     

绿色贸易壁垒与农业生态环境保护

概述了世界贸易组织有关绿色贸易壁垒的原则和规则。阐述了欧盟的有关农产品质量标准和农产品标准的管理法规。分析了绿色贸易壁垒对我国农业结构战略性调整带来的影响以及对农业生态环境建设所提出的要求。最后，提出了我国克服绿色贸易壁垒的措施和手段。     

论长春市绿地生态系统的建设措施

城市的绿地生态系统为城市的可持续发展提供了物质空间基础，分析了长春市目前的绿地系统的现状，及绿化用地的潜力，提出了实行绿地系统的总量控制、构建绿色空间网络体系、均衡绿地系统布局；推广立体绿化等具体的建设措施。