绿化树种对大气金属污染物吸滞能力

研究测定了部分城市绿化树种对重金属大气铅、镉污染物的吸滞能力。结果表明：绿化树种对大气铅、镉污染物具有一定的吸收净化能力，并依污染气体和树种的不同具有明显差异；对铅吸收量高的树种有：桑树、黄金树、榆树、早树、梓树；吸镉量高的树种有：美青杨、桑树、早树、榆树、梓树、刺槐。     

我国珍贵树木保护中若干法律问题的思考

保护珍贵树木具有十分重要的意义,本文从立法、司法的角度,归纳了当前我国保护珍贵树木的法律制度及相关的法律责任,对于进一步完善与珍贵树木保护相关的法律规定提出了自己的设想.     

Safety evaluation of leak in a storage tank using fault tree analysis and risk matrix analysis

The work presented in this paper used a quantitative analysis of relevant risks through the development of fault tree analysis and risk analysis methods to aid real time risk prediction and safety evaluation of leak in a storage tank. Criticality of risk elements and their attributes can be used with real time data to predict potential failures likely to occur. As an example, a risk matrix was used to rank risk of events that could lead to a leak in a storage tank and to make decisions on risks to be allowed based on past statistical data. An intelligent system that recognizes increasing level(s) and draws awareness to the possibility of additional increase before unsafe levels are attained was used to analyse and make critical decisions. After a visual depiction of relationships between hazards and controls had been actualized, dynamic risk modelling was used to quantify the effect controls can potentially have on hazards by applying historical and real-time data into a probabilistic model. The output of a dynamic risk model is near real-time quantitative predictions of risk likelihood. Results from the risk matrix analysis method mixed with RTD and FTA were analyzed, evaluated, and compared.     

一种橡胶密封圈的剩余贮存寿命评估方法

目的评估已随武器装备贮存一段时间后的旧橡胶密封圈的剩余贮存寿命。方法利用旧橡胶密封圈在加速老化试验中实际产生的压缩永久变形,外推其在贮存温下的老化动力学方程,进而以失效临界值为输入,计算橡胶密封圈的剩余贮存寿命。结果建立了面向旧橡胶密封圈的剩余贮存寿命评估方法。结论该方法适用于旧橡胶密封圈的剩余贮存寿命评估。     

利用‘树皮''进行大气污染历史监测的新采样方法

1　IntroductionBesidestheusualsamplingmethods,theconcentrationsofpollutantsintreebarkandtreebarkpockethavebeenproposedforevaluatingthedegreeofairpollutionofpresentandinthepast[1— 4 ].Inthisstudytheconcentrationsofleadandcadmiumintheoutertreebarksofredbud…     

生态茶园建设与病虫害综合防治

综述了在茶树病虫害综合防治中生态学原理和农田生态系统科学理论的运用。强调以生态防治，即农业防治和生物防治为主，借助于各种农业技术和现代生物科学手段，在综合防治中尽量少用化学农药，以减少对环境的污染、农药残留及对天敌的伤害，维持茶园生态平衡。     

形率法测算单株立木材积公式选用

单株立木求积,是林业科研和生产的重要内容.本文通过对临武县杉木人工林分590株标准木进行测算研究,发现不同的立木求积式其求积精度有明显差异,由此优选出精度高简便实用的测算公式.     

山东省高速公路主要绿化树木叶片硫、铅含量分析

汽车尾气会给高速公路路域环境带来一定程度的硫(S)、铅(Pb)污染,而绿化树木可通过吸收作用从而有效降低这些污染物在空气中的含量,目前这方面的研究较少。对山东省高速公路路侧主要绿化树木叶片S、P质量分数的研究表明,I107杨树(Populus Linn.)叶片S、Pb质量分数与高速公路车流量呈显著正相关。I107杨树叶片S、Pb质量分数对高速公路路域环境污染具有一定指示作用,不同路段杨树叶片的S、Pb质量分数存在明显差异,济青高速公路路侧杨树叶片的S、Pb质量分数最高,其次是京沪高速,最低的是日东高速。I107杨和龙柏对S污染物的吸收能力较强,其次是垂柳(Salix babylonica L.),较差的是紫叶李(Prunus cerasifera cv.Pissardii.)、大叶女贞(Ligustrum lucidumAit)和雪松(Cedrus deodara(Roxb.)Loud);而I107杨和紫叶李对Pb的吸收能力较强。     

Relation Between Individual Tree Mortality and Tree Characteristics in a Polluted and Non-Polluted Environmentx

Data on individual tree mortality in relatively healthy (Berezinskiy biosphere reserve) and damaged (surroundings of the mineral fertilizer plant ‘Achema’) even-aged Scots pine (Pinus sylvestris L.) stands are presented. Tree size and competition intensity were found to be the most significant predictors of individual tree mortality in all age groups of the relatively healthy Scots pine stands, however, an essential reduction in the closeness of relations between the tree mortality rate and these variables was determined with the aging of stands. An exponential decrease in tree mortality probability with an increase of tree size is characteristic for trees suffering different competition intensity, however, this decrease becomes much more pronounced as the competition pressure increases. The relations of different tree and stand variables with tree mortality probability have been found to become much weaker in the polluted environment. An exponential increase in tree mortality probability with an increase of crown defoliation was characteristic of damaged Scots pine stands, however, the rate of the increase was different in different age and diameter classes. The impact of crown defoliation on tree mortality rate increased with the aging of stands. At the same defoliation level, individual tree mortality probability was much higher for smaller suppressed trees, however, a relative increase in tree mortality probability along with an increase of crown defoliation was more pronounced for dominant trees. Conclusion: a higher mortality of damaged (defoliated) trees should be considered while assessing losses in forest productivity in a polluted environment.     

Ice Storm Damage and Early Recovery in an Old-Growth Forest

We quantified the damage causedby a major ice storm to individual trees in two1-ha permanent plots located at Mont St. Hilairein southwestern Québec, Canada. The storm, whichoccurred in January 1998, is the worst on recordin eastern North America; glaze ice on the orderof 80–100 mm accumulated at our study site. Allbut 3% of the trees (DBH 10 cm) lost at leastsome crown branches, and 35% lost more than halftheir crown. Damage to trees increased in the order: Tsuga canadensis, Betula alleghaniensis, Ostrya virginiana, Acer saccharum, Fagus grandifolia, Quercus rubra, Betula papyrifera, Acer rubrum, Tilia americana, and Fraxinus americana. Only 22% of the saplings and small trees (4 cm < DBH < 10 cm)escaped being broken or pinned to the ground byfalling material. Levels of damage generally weregreater in an exposed ridge top forest than in acove protected from wind. By August 1999 only53% of the trees had new shoots developing fromthe trunk or broken branches; among the moredominant canopy trees, Fagus grandifoliahad the least sprouting and Acer saccharumand Quercus rubra the most. We anticipateand will monitor both significant turnover in thetree community and some shift in composition ofthe canopy dominants.