Rehabilitation of a lowland river: Reconciling flood defence with habitat diversity and geomorphological sustainability

Geomorphologically appropriate rehabilitation measures were proposed to enhance the in-stream environment of the lowland River Idle, north Nottinghamshire, UK. However, the River Idle has multi-functional management requirements including those of flood defence so environmental enhancement must be pursued without significantly increasing the flood risk. Hydraulic testing of rehabilitation proposals is complicated because of the stringent assumptions about flow and morphology in ‘traditional’ hydraulic models. While new generation two- and three-dimension hydraulic models may overcome some of these problems, they are extremely data intensive, require advanced modelling capabilities and are, therefore, very expensive to apply. Also, they do not yet predict morphology-flow interactions adequately. As an alternative, several simple hydraulic models were applied to test the rehabilitation proposals, based on a fitness-for-purpose criterion.BENDFLOW was applied to fine tune the optimal siting of measures and to estimate the additional near-bank scour generated by proposed bend re-profiling. HMODEL2 and the FCFA method were used to test the impact on local channel conveyance capacities and HECRAS was applied to simulate the impact of the proposals on regional flood defence. Indicative results from the testing suggested a maximum increase in near-bank scour of 0·15 m in re-profiled bends, a loss of approximately 10% in flood conveyance locally due to deflector installation or reed and tree planting, and a 0·12 m increase in flood stage within the reach for a 15 year flood. The modelling results were acceptable to the management authority as an indication of an acceptable compromise between flood defence and conservation interests, and construction of the measures followed in 1996. It is clearly that it will require the results of post-project monitoring to indicate whether compromises made to the rehabilitation initiatives in order to satisfy flood defence requirements have unduly reduced their environmental enhancement potential but, for assessing the proposed methods, the models are recommended for use other lowland river environments.     

Hazardous waste indicators for national decision makers

Indicators and indices are important tools that assist decision makers to formulate and implement plans for management at local, national and international levels. Four indicators for hazardous waste management are described that have recently been adopted within the United Nations framework of Indicators of Sustainable Development. Although these four indicators will be useful tools, the need for a broader range of policy-relevant qualitative and quantitative indicators, proxy indicators and indices is outlined. The argument is advanced that in order for all nations to better manage the range of hazardous waste issues, including waste generation, export/import and disposal, a set of innovative indicators and indices is required. Useful indicators and indices are described that could be used to link and quantify likely environmental, ecosystem and health impacts and risks especially from hazardous waste disposal. Indicators are also suggested that could be used to illustrate the shift in industrial strategy away from end-of-pipe processes towards waste recycling, cleaner production and integrated life-cycle analysis. It was concluded that until the lack of reliable and harmonized data on hazardous waste is addressed, indicator development and use by national and international decision makers cannot readily be implemented.     

胶带输送机防尘治理综合改进措施

叙述了胶带输送机现有防尘罩的不足及改进措施。     

联苯代谢对微生物的生长胁迫及分裂抑制

以联苯/多氯联苯降解菌株R04（Rhodococcus sp.R04）和几种模式微生物为研究对象，利用高效液相色谱、荧光显微镜、扫描电子显微镜等分析微生物在联苯及其代谢物培养条件下细胞分裂和形态的变化.结果表明联苯及其代谢产物对红球菌R04和几种模式微生物细胞的分裂有抑制作用，并对部分微生物形态有影响.与前体-联苯及其代谢产物2-羟基-6-酮基-6-苯基-2，4-己二烯酸相比，2，3-二羟基联苯对G⁺、G^-细菌，或是酵母细胞分裂都有较强的抑制和形态的改变.2，3-二羟基联苯导致R.R04和缺陷型R.R04细胞形成不完整隔膜的比例增加；造成96.4%的大肠杆菌BL21细胞表面凹陷，胞质内容物流失，菌体体积缩小；导致枯草芽孢杆菌89.6%的细胞体积明显缩小；导致金黄色葡萄球菌基本没有细胞能形成完整的分裂隔膜；导致红酵母细胞能进行出芽生殖的比例从64.2%降低到19.3%，但对其细胞形态无明显改变.联苯代谢物2，3-二羟基联苯对红球菌R04及其它微生物细胞分裂和增殖的抑制作用比其前体-联苯强，建议在研究环境化合物与微生物互作时，应考虑环境化合物代谢的毒性效应.     

Communication ecology of webbing clothes moth: 4. Identification of male- and female-produced pheromones

Summary. We investigated the hypothesis that aggregation signals produced by male webbing clothes moths (WCM), Tineola bisselliella (Hum.) (Lepidoptera: Tineidae), and close-range male attractant signals produced by females have a pheromonal basis, at least in part. Gas chromatographic-electroantennographic detection (GC-EAD) and GC-mass spectrometric analyses of bioactive methanolic extracts of male WCM disclosed three candidate pheromone components: hexadecanoic acid methyl ester (16:Ester), (Z)-9-hexadecenoic acid methyl ester (Z9—16:Ester), and octadecanoic acid methyl ester (18:Ester). In bioassay experiments in a large Plexiglas™ arena, a blend of synthetic 16:Ester plus Z9—16:Ester was attractive to male and virgin (but not mated) female WCM; the 18:Ester was inactive. GC-EAD analyses of pheromone gland extracts from female WCM revealed (E,Z)-2,13-octadecadienal (E2Z13—18:Ald) and (E,Z)-2,13-octadecadienol (E2Z13—18:OH) as candidate sex pheromone components. In arena bioassay experiments, 1—5 female equivalents of synthetic E2Z13—18:Ald (0.2 ng) and E2Z13—18:OH (0.1 ng) were more attractive to male WCM than were two virgin female WCM. We anticipate that the combination of aggregation and sex pheromones, male-produced sonic aggregation signals, and habitat-derived semiochemicals will be highly effective in attracting male and female WCM to commercial traps. Received 12 January 2001; accepted 8 June 2001.     

Decision-making for fire use among farmers in savannas: an exploratory study in the Distrito Federal, central Brazil

Today, fire in the Braziliancerrado(savanna) is predominantly caused by farmers. They use fire during the dry season to promote fresh grass regrowth in pastures for their cattle and to clear areas of planting ready for cultivation in the wet season. This study researched fire use by farmers in thecerradoof the Distrito Federal, central Brazil, in order to investigate what influences their fire management decision-making. The results show that the two main factors limiting the choice of feasible options for farmers to meet their objectives are income and time. However, perceptions also play a major role in the decision-making process, and for many farmers this alone determines whether fire is used. Various fire practices involved with timing, frequency and size, as well as precautions taken before and during the burn, and the factors influencing these decisions are presented. This study shows that it is vital to understand factors determining fire use if effective fire management plans and policies are to be developed.1998 Academic Press     

环境中的主要人工辐射源及其剂量

本文论述了因人类活动而产生的主要人工辐射源的来源、种类以及对人的辐照剂量的估计。     

Chemical trail communication in the amblyoponine species Mystrium rogeri Forel (Hymenoptera, Formicidae, Ponerinae)

Summary. Workers of the amblyoponine species Mystrium rogeri employ trail communication during recruitment to food sources and new nest sites. The trail pheromone originates from a hitherto unknown sternal gland located in the 7th abdominal sternite. The recruiting ant deposits the gland secretions by a special gaster-dragging behavior. The recruitment behavior can be complemented by a rapid vertical body shaking performed by some recruiting ants inside the nest. M. rogeri workers possess a large pygidial gland, the secretion of which elicits a repellent response in other ant species. Received 25 May 1998; accepted 15 June 1998.     

Experiments comparing the use of kites and gas bangers to protect crops from woodpigeon damage

Woodpigeon damage to spring cabbage on two farms in different years was greatly reduced when a large kite was flown over the fields. Protection continued for over 3 months with no sign of habituation to the kite by pigeons. Woodpigeons avoided flying or settling within 250 m of the kite. Damage in fields with a gas banger exceeded that in fields with a kite, especially in severe winter weather. “Humming line” proved ineffectual in reducing damage. On these lowland farms it was necessary to launch the kite on most mornings, but if such launching can be carried out, kites can be effective in reducing damage by woodpigeons.