高强度埋纱绿色包装袋纸的开发应用

阐述了高强度埋纱绿色包装袋纸是纸/塑复合或塑/塑复膜的污染环境包装材料的替代产品，生产流水线由5项专利技术为基础构成，生产原料来源充足，体现资源循环利用，生产企业经济效益显著，产品具有撕裂度，抗张强度高，抗水防潮，耐热，牢固度好，破包率低，指出产品可为国家节约大批木材，对保护森林资源贡献巨大，产品生产过程中不对环境造成污染。     

固定化SRB吸附乳酸钠的动力学及再生动力学研究

用聚乙烯醇包埋硫酸盐还原菌(SRB),探讨固定化SRB小球的动力学规律及再生动力学控制机理,同时利用膜扩散控制模型与粒内扩散控制模型,描述固定化SRB小球循环吸附乳酸钠的动力学过程,计算出不同条件下的膜扩散系数D/δ和粒内扩散系数D的值.通过对固定化SRB小球吸附乳酸钠的动力学和再生动力学研究,为固定化SRB小球的营养源吸附与再生工艺参数的确定提供理论依据.     

生物法净化再生胶生产废气工业试验研究

在再生橡胶厂进行橡胶再生低浓度有机废气的生物法净化工业试验研究，对于甲苯浓度为300～1400mg/m^3的再生胶脱硫废气，在常温常压下以气体流量10～20m^3/h、循环液体喷淋量300～500L/h运行生物法废气净化装置获得了良好物净化效果。该装置连续运行100d的结果显示，其对再生胶废气中甲苯的净化效率可较长时间的保持在90%左右，废气经处理后可以实现达标排放，废气处理成本约为工厂再生胶产值的0.12%～0.14%，具有明显的技术先进性和经济合理性。     

废柴油再生工艺的研究

以石油破乳剂DPA2 0 3 1为絮凝剂、活性白土为吸附剂 ,经絮凝、吸附再生处理了废柴油。考察了影响絮凝、吸附的各种因素。确定最佳絮凝条件 :温度 80℃、混合时间 45min、10 0g废柴油所需石油破乳剂 2 g ;净化油收率 82 %、透光率 3 9 5 %。最佳吸附条件 :每 10 0 g净化油活性白土用量 15g、硅酸钠 3 g、温度 75℃、时间 40min ;精制油收率 89%、透光率 83 %。精制油的一些理化指标符合国家标准     

废塑料资源化新技术及其进展

随着社会的发展 ,人们对物质的要求日益增大 ,而自然资源和能源却日趋匮乏 ;另一方面 ,可再生利用的高分子材料的消耗所产生的废弃物也造成了严重的污染 ,威胁到人类的生存。有人提出废旧塑料的资源化是 2 1世纪全人类的重要课题。本文综述了国内外废旧塑料资源化新技术及其进展。     

Predicting tree species presence and basal area in Utah: A comparison of stochastic gradient boosting,generalized additive models,and tree-based methods

Many efforts are underway to produce broad-scale forest attribute maps by modelling forest class and structure variables collected in forest inventories as functions of satellite-based and biophysical information. Typically, variants of classification and regression trees implemented in Rulequest's^© See5 and Cubist (for binary and continuous responses, respectively) are the tools of choice in many of these applications. These tools are widely used in large remote sensing applications, but are not easily interpretable, do not have ties with survey estimation methods, and use proprietary unpublished algorithms. Consequently, three alternative modelling techniques were compared for mapping presence and basal area of 13 species located in the mountain ranges of Utah, USA. The modelling techniques compared included the widely used See5/Cubist, generalized additive models (GAMs), and stochastic gradient boosting (SGB). Model performance was evaluated using independent test data sets. Evaluation criteria for mapping species presence included specificity, sensitivity, Kappa, and area under the curve (AUC). Evaluation criteria for the continuous basal area variables included correlation and relative mean squared error. For predicting species presence (setting thresholds to maximize Kappa), SGB had higher values for the majority of the species for specificity and Kappa, while GAMs had higher values for the majority of the species for sensitivity. In evaluating resultant AUC values, GAM and/or SGB models had significantly better results than the See5 models where significant differences could be detected between models. For nine out of 13 species, basal area prediction results for all modelling techniques were poor (correlations less than 0.5 and relative mean squared errors greater than 0.8), but SGB provided the most stable predictions in these instances. SGB and Cubist performed equally well for modelling basal area for three species with moderate prediction success, while all three modelling tools produced comparably good predictions (correlation of 0.68 and relative mean squared error of 0.56) for one species.     

Estimating the Effect of Protected Lands on the Development and Conservation of Their Surroundings

Abstract:  The fate of private lands is widely seen as key to the fate of biodiversity in much of the world. Organizations that work to protect biodiversity on private lands often hope that conservation actions on one piece of land will leverage the actions of surrounding landowners. Few researchers have, however, examined whether protected lands do in fact encourage land conservation nearby or how protected lands affect development in the surrounding landscape. Using spatiotemporal data sets on land cover and land protection for three sites (western North Carolina, central Massachusetts, and central Arizona), we examined whether the existence of a protected area correlates with an increased rate of nearby land conservation or a decreased rate of nearby land development. At all sites, newly protected conservation areas tended to cluster close to preexisting protected areas. This may imply that the geography of contemporary conservation actions is influenced by past decisions on land protection, often made for reasons far removed from concerns about biodiversity. On the other hand, we found no evidence that proximity to protected areas correlates with a reduced rate of nearby land development. Indeed, on two of our three sites the development rate was significantly greater in regions with more protected land. This suggests that each conservation action should be justified and valued largely for what is protected on the targeted land, without much hope of broader conservation leverage effects.     

林窗大小和位置对丽江云杉自然更新幼苗存活和生长的影响

通过 1997～ 2 0 0 0年对 32个林窗的连续观测调查 ,研究了滇西北玉龙雪山自然保护区云杉坪亚高山丽江云杉林林窗大小和林窗位置对自然更新幼苗存活和生长的影响 .4个生长季节的观测结果表明 :林窗与林下非林窗内的幼苗大小和幼苗存活数量差异明显 .林窗由小到大 ,单位面积内的自然更新苗木数量逐渐减少 ,小林窗中更新苗为大林窗的 5倍左右 ,而林下的更新苗很少 ,0 .2ind .10m-2 .中等林窗和小林窗内的幼苗数量在从南到中心到北的位置上几乎没有明显的差异 ;大林窗中存在由南到北的位置差异 ,更新幼苗数量逐渐减少 .从更新幼苗的生长来看 ,中等林窗内的幼苗 ,高度最大、生长最快 ,定居阶段的平均年高生长为 (7.1± 0 .5 )cma-1,小林窗次之 ,大林窗和林下幼苗个体最小 ,生长最慢 .进一步从林窗位置来看 ,中、小林窗幼苗大小几无位置差异 ,大林窗则由南到北 ,幼苗由大变小 .从幼苗存活数量和大小来看 ,中等林窗大小是丽江云杉幼苗更新的适宜面积 ,对该类型退化亚高山针叶林恢复提供了一定的参考 .图 4表 2参 2 3     

Cost-effective forest conservation and criteria for potential conservation targets: a Finnish case study

Selecting reserves for forest biodiversity maintenance is often done by setting criteria for components of structural elements of biodiversity, such as a volume of decaying wood. We tested how the different threshold values for the components of structural elements affect the cost-effective site selection. Using Finnish National Forest Inventory information and remote sensing data, we determined a habitat quality index and economic value for each site in Satakunta region in Finland. Moreover, we defined several sets of potential conservation targets using alternative criteria for the habitat quality index developed for the Finnish case study. These figures were used in the site selection model in order to maximize the sum of habitat index of selected areas under a given budget constraint. We found that the production possibility frontier for the outputs of timber and biodiversity is only slightly concave when using the given threshold values. Thus, the optimal combination of the outputs is sensitive to the relative values of these goods. Our results suggest that an integrated approach in forest conservation could provide to environmental managers considerable cost savings compared with current management practices. Environmental managers could also reduce conservation costs by loosening the criteria for potential conservation targets. This would not lower considerably the quality of conserved forests.     

Value Orientation and Forest Management: The Forest Health Debate

Among both forest practitioners and the general public, “forest health” has become an issue of contention. Whereas the debate over which treatments will best achieve healthy forests has been framed largely by the popular media and politicians as a struggle between industry and environmentalists, the views of the general public remain unexplored. Survey results from Oregon and Washington residents were used to assess the relationships between respondents’ self-described environmental or economic priorities and the following two variables: (1) acceptability of forest management practices and (2) perceived threats to forest health. Findings indicate that active management was generally accepted by a majority of respondents regardless of their environmental or economic orientation. Disagreement emerged, however, when the appropriateness of specific management practices within specific forest conditions was examined. Additionally, strong evidence was found for a relationship between self-described environmental or economic orientation and perceived threats to forest health. Those with an environmentally oriented viewpoint tended to perceive human-caused factors as the largest threats, whereas those with an economic orientation saw naturally occurring processes as the greatest threats. These findings suggest that the issue of contention is not active management per se. Rather, the major divisions in the forest health debate are defined by specific contexts and circumstances, as well as the management practices used.