THE IMPACTS OF WATERWAY USER FEES ON GRAIN TRANSPORTATION ON THE SNAKE-COLUMBIA RIVER1

ABSTRACT: Grain transportation is a major economic activity on the multiple use Snake-Columbia River System. Congress is currently considering increased transportation user fees aimed at recapturing federal expenditures for waterway operations and maintenance. Three types of fee structure and four levels of cost recovery are evaluated using a network program model. In each case traffic is diverted away from the river to other Puget Sound ports via truck and rail transport modes. Grain shippers in the region will be adversely affected by a higher transport bill. The Lower Columbia River port economic activities will be negatively affected; however, competitive uses of the river, recreation, and hydroelectric generation will likely benefit modestly.     

Niche separation in two species of hare. Metabolic costs of plant phenolics

Summary The distributions of mountain hare (Lepus timidus) and European hare (L. europaeus) overlap in central Sweden, but they occupy separate food niches in winter. In Scandinavia, the European hare is mainly a grazer while mountain hare is a predominant browser. Browse contain high amounts of secondary metabolites, such as phenols, compared to grass. This raises the question if the two hare species differ in their metabolic tolerance of plant phenols and that these differences influence their food choice.Phenolic excretion in urine increased significantly with phenolic intake in both species. Excretion of glucuronic acid conjugates, one of the major pathways of elimination of phenols in both hare species, is positively correlated to phenolic intake and excretion. However, the extent of excretion of phenolics by this route was different in the two species of hare. European hares excreted substantially more glucuronic acid per amount of phenolics than mountain hare. The phenols were metabolized to a larger extent in the mountain hare, indicating a higher detoxification capacity. From these results it is likely that European hare have a higher cost for the detoxification of plant phenols compared to mountain hare. This cost and negative effect on sodium balance when feeding on browse may prevent exploitation of forest habitats by European hares, whereas mountain hare are better able to do so.     

FEATURES OF THE ECOSYSTEM IN THE SUBTROPICAL KARST MOUNTAIN AREA AND THE WAYS OF ITS RECOVERY

FunctionalfeaturesoftheecosystemintheprimitivesubtropicalkarstmountainareaandtheirdegradationundertheinfluenceofhumanactivitiesInthepast 50years ,humanactivitieshavebroughtaboutthefollowinggreatchangesintheecosystemofthesubtropicalkarstmountainarea :(1 )FromtheinvestigationandanalysisofMaolanKarstNaturalConservationDistrictinGuizhouandNonggangKarstNaturalConservationDistrictinGuangxi,andtheresearchesonthechangesinthenaturalandgeographicalenvironmentinthekarstmountainareainRenhuaiCity ,Gu…     

机械制造工厂噪声污染的控制对策

分析了机械制造工厂的噪声来源，并针对其噪声源特点，提出了降低噪声的技术措施和行政管理措施。     

依靠科技进步，实现跨越式发展

结合西部地区的科技现状,分析了科技创新的内在要求,探讨了实现跨越式发展的途径和对策。     

循环经济是可持续发展战略的必然选择和实现方式

人类在解决资源、环境与发展、生态与保护的关系问题中,循环经济成为可持续发展战略的实现方式具有客观必然性。深入、系统地梳理历史选择进程与理论创新成果,有助于对我国的循环经济实践提供强有力的理论支持。     

反硝化脱硫菌的代谢特征及其环境应用研究进展

反硝化脱硫菌(NR-SOB)是一种具有同步硝酸盐还原和硫氧化能力的功能微生物。探讨了NR-SOB的代谢特征及其影响因素,并对它在废水处理,防腐,天然气、工业废气脱硫方面的应用进行了综述。最后,还指出了今后NR-SOB在环境应用方面的研究方向。     

多溴联苯醚与四溴双酚A的生物代谢研究进展

分析了生物体内多溴联苯醚（PBDEs）和四溴双酚A（TBBPA）的来源和分布,综述了PBDEs和TBBPA在生物体内发生还原代谢和氧化代谢的研究进展,从体内原位代谢和体外模拟代谢2个方面探讨了PBDEs和TBBPA的生物代谢机制、代谢途径及代谢中可能涉及的代谢酶,指出今后应进一步深入开展PBDEs和TBBPA的生物积累和代谢产物的定量分析的研究。     

四川省环境科技研究方向与任务

本文通过对四川省环境特点的分析与环境科技工作的回顾,提出四川省环境科技研究方向与任务的建议,与环境科技管理及研究人员共同研讨。     

河南省农业自然资源可持续利用途径

农业的持续发展依赖于农业自然资源的可持续利用。根据可持续发展思想,通过分析河南省农业自然资源的现状和资源利用中存在的主要问题,作者提出了实现该省农业自然资源可持续利用的途径。