森林景观信息网络化简介及其应用

介绍应用国际互联网传播森林景观信息和网上旅游服务概况,论述了森林景观数字信息的几种计算机实现方法,并展望森林景观信息网络化前景。     

公益林与商品林分类指标体系及技术标准的研究

林业分类经营是林业部提出的一项深化林业改革的重要措施,如何科学合理地划公益林与商品林,是当前实施林业分类经营战略迫切需要解决的问题。本文从系统、可行、科学的角度对森林功能性分类系统,划分公益林与商品林的分类指标体系及技术指标进行了探讨。     

森林生态资源配置中的市场失灵及其对策

森林生态系统是地球上最大的陆地生态系统。森林生态体系建设中的公益林,具有公共物品非排他性和非排斥性的特征,由此带来的外在性是市场失灵的一个重要因素,它将导致生态资源配置的长期低效。只有较好地化解市场失灵,才能有效地协调生态效益与经济效益,确保我国森林生态体系建设的优质与高效。本文通过对森林生态建设中市场失灵的分析,提出了产权结合,科斯定理,生态质量等级价格等对策,以修正市场的部分失灵。并探讨了木材价格变动对生态供给的影响,进而提出当木材价格变动时应适时调整生态质量价格,以保证有效的生态供给     

温度升高对酸化森林土壤渗滤水化学组成的影响

用德国Solling地区挪威云杉林的严重酸化的未扰动土柱 ,在 1年半时间内 ,研究了在不存在干旱的条件下温度升高对渗滤水化学组成的影响。当平均气温由 1 2 3℃上升到 1 5 5℃时 ,土壤有机质分解速度明显加快 ,Norg、Corg、SO42 -的浓度和净淋失量明显增加 ,Al3+、NO3-的浓度和净淋失量明显降低 ,NH4+、HPO42 -、Cl-的浓度和净淋失量以及渗滤水的Ca2 +/Al3+比轻微增加 ,H+的浓度和净淋失量轻微降低 ,盐基离子则无明显变化。温度升高导致的反硝化作用增强是Al3+浓度降低的关键因素。简而言之 ,温度升高在一定程度上缓解了Al3+毒害 ,但并未改善盐基离子营养状况。     

对我国21世纪森林病虫鼠害防治体系的展望

根据中国森林病虫鼠害防治现状及国际科学研究进展,研究了２１世纪森林病虫鼠害的研究方向和科学管理战略,提出了研究重点、目标及管理机构的建制。     

Variation in quality and decomposability of red oak leaf litter along an urban-rural gradient

 This study tested whether urban land use can affect the chemistry and decomposability of Quercus rubra L. (red oak) leaf litter in forests within and near a large metropolitan area. Cities may affect the quality of leaf litter directly through foliar uptake of atmospheric pollutants, and indirectly through alterations in local climate and changes in soil fertility caused by pollutant loads and altered nutrient cycling regimes. Using a microbial bioassay, we tested whether red oak leaf litter collected from urban and suburban forests in and near New York City differed in decomposability from litter of the same species collected from rural forests 130 km from the city. We found that oak litter from the urban forests decayed 25% more slowly and supported 50% less cumulative microbial biomass in a laboratory bioassay than rural litter. Rural litter contained less lignin and more labile material than urban litter, and the amounts of these chemical constituents were highly correlated with the decay rate coefficients and integrated microbial growth achieved on the litter. The specific causes of the variation in litter chemistry are not known. The results of this study suggest that decomposer activity and nutrient cycling in forests near large cities may be affected both by altered litter quality and by altered biotic, chemical and physical environments. The sensitivity of the microbial bioassay makes it useful for distinguishing differences in within-species litter quality that result from natural or anthropogenic variation in the environment. Received: 7 January 1999     

都市农业及其环境保护

阐述了都市农业的概念与范畴,北京市都市农业发展特点及其发展过程中废弃物类型、主要环境问题、废弃物处理与资源化的途径以及发展资源综合利用型都市农业的重要性,并提出了都市农业发展方向与对策和北京市都市农业的分区发展规划。     

实施农业持续发展之我见

科学技术是第一生产力。作为农业大国、大省,农业生产的持续发展必须依靠科学技术。农业应用基础理论的研究,新品种,新方法的突破和更新;农民科技意识的培养和文化素质的提高;农业产业结构的合理布局和各种资源的有效充分的利用,都将极大地促进农业生产发展,并达到持续发展的目的。     

Environmental values and forest patch conservation in a rural Costa Rican community

Although conservation attention has generally focused on large forest tracts, there is increasing evidence that smaller forest patches are important for both conservation and rural development. A study of forest patch conservation in a rural Costa Rican community found that, although forest patch conservation was influenced by landholding size, material factors did not account for all the variation in forest patches conservation behavior or conservation orientations of farmers. A qualitative interpretive approach, using semi-structured interviews, found that environmental values were influenced by at least three factors. First, colonist farmers with direct experience with environmental degradation in other regions of Costa Rica were more likely to be concerned about environmental degradation. Second, childhood exposure to conservation played an important role in influencing conservation orientations. Third, the environment was frequently discussed in relation to the moral and social values present in religious doctrines. The study also found general support for forest conservation laws, and a clear indication that interest in forest conservation has grown in recent years. The study highlights the importance of environmental values, in conjunction with material factors, in influencing forest conservation in rural communities.     

利用地面活动的节肢动物进行农田生态环境监测的研究

1993年10月至1995年3月在湖北省潜江市郊,用陷井法进行了地面活动的节肢动物作为农田生态环境监测指标的研究.结果表明:①用陷井法监测地面活动的节肢动物,全年的调查频率以4～9月每月1次为好.②该地区用于监测的关键节肢肢动物可以通过因子分析的方法来选择.③在一个地区,多样化农田景观元素的合理镶嵌是保护有益节肢动物,充分发挥农业生态系统自控功能的有效途径.