天津港的发展与环保规划设想

阐述了天津港的发展前景，对港区环境质量现状和环保设施作了全面的调研，根据可持续发展的思想，提出了与天津港发展相应的环保规划设想。     

论21世纪中国农业可持续发展──有关理论与实践的讨论

文章讨论了可持续农业的定义与实际含义，对发展与环境、现代农业的功与过、替代还是发展、传统技术与现代科学技术的关系等理论问题进行了探讨并提出相应的见解，重点是强调生产持续性、经济持续性与生态持续性三者的统一，强调前进而不要后退。文章还探讨了中国农业发展的方向与道路，根据中国农业４５年成就与不足以及面临的难题，提出２１世纪目标──实现农业现代化，而集约持续农业是中国式通向农业现代化的具体道路的体现。强调集约（高产高效）与持久发展的结合，在农业上要狠下真功夫。     

Prevention of railway trespassing by automatic sound warning—A pilot study

Objective: The objective of this study was to investigate the effects of a sound warning system on the frequency of trespassing at 2 pilot test sites in Finland.

Methods: The effect of automatic prerecorded sound warning on the prevention of railway trespassing was evaluated based on observations at 2 test sites in Finland. At both sites an illegal footpath crossed the railway, and the average daily number of trespassers before implementation of the measures was about 18 at both sites.

Results: The results showed that trespassing was reduced at these sites by 18 and 44%, respectively. Because of the lack of proper control sites, it is possible that the real effects of the measure are somewhat smaller.

Conclusions: The current study concludes that automatic sound warning may be efficient and cost effective at locations where fencing is not a viable option. However, it is not likely to be a cost-effective panacea for all kinds of sites where trespassing occurs, especially in countries like Finland where trespassing is scattered along the railway network rather than concentrated to a limited number of sites.     

Effects of Soil Moisture Variations on Deposition Velocities Above Vegetation

The parameterized subgrid-scale surface flux (PASS) modelprovides a simplified means of using remote sensing data from satellites and limited surface meteorological information to estimate the influence of soil moisture on bulk canopy stomatalresistances to the uptake of gases over extended areas.PASS-generated estimates of bulk canopy stomatal resistance were usedin a dry deposition module to compute gas deposition velocitieswith a horizontal resolution of 200 m for approximately 5000 km² of agricultural crops and rangeland. Results were compared with measurements of O₃ flux and concentrations made during April and May 1997 at two surface stations and from an aircraft. The trend in simulated O₃ deposition velocityduring soil moisture drydown over a period of a few days matchedthe trend observed at the two surface stations. For areas underthe aircraft flight paths, the variability in simulated O₃ deposition velocity was substantially smaller than the observedvariability, while the averages over tens of kilometers were usually in agreement within 0.1 cm s^-1. Model results indicated that soil moisture can have a major role in depositionof O₃ and other substances strongly affected by canopy stomatal resistance.     

The Importance of Mixing Height in Characterising Pollution Levels from Aerosol Optical Thickness Derived by Satellite

In the present study the horizontal distribution of columnar aerosol optical thicknessderived at high spatial resolution from Earth observation satellite data in the Lombardy area (Italy) was converted to the horizontal distribution of optically effective aerosols concentration at the ground level. This was achieved by incorporating information on atmosphere's mixing height, at which pollutants released at ground level are vertically dispersed by convection or mechanical turbulence. The resulted fields compared favourably to pollutant concentration measurements provided by the ground stations. These results show that it is possible to calculate mean concentration fields by using the spatial distribution of aerosol optical thickness (AOT) measured by satellite normalized by the atmospheric mixing height. The advantage of satellites in measuring AOT is that they can capture all actual emissions compared to the models, which are based on inventoried data.     

城市扬尘污染长效管理机制研究

城市扬尘是影响空气质量、危害居民身体健康的污染源之一。本文进行了上海市杨浦区扬尘源解析,从类型上将扬尘分为建筑施工扬尘、道路施工扬尘和堆场扬尘。引用相关经验公式计算出杨浦区三类扬尘的起尘量大小顺序为：建筑施工〉道路施工〉堆场,并分析评价了杨浦区近两年扬尘排放量的时空变化。针对杨浦区的自身特点,以目标体系、标准体系、责任体系、管理体系、监督体系为框架,初步建立了扬尘污染管理的长效管理机制。     

干水在热环境中的持续作用效果研究*

为研究干水对建筑火灾中高聚物燃烧产生的热危害和烟气危害的影响,采用火焰传播量热仪（FPA）模拟建筑火灾扑灭后的持续热环境,对灭火过程中过量施加的干水对可燃高聚物的持续作用效果进行研究。结果表明:干水能够明显提升可燃物的抗复燃性能以及削弱燃烧过程中的热危害和烟气危害;相比于纯燃料,干水作用下可燃物的点燃时间出现明显的延迟,并且热释放速率和一氧化碳生成速率明显降低,尤其在可燃物燃烧初期,干水还具有显著的抑制烟气生成速率的效果。研究结果可为灾后消防人员的搜救和被困人员的逃生提供一种新的技术方案。     

Satellite Observations of Lava Lake Activity at Nyiragongo Volvano, Ex-Zaire, during the Rwandan Refugee Crisis

In June 1994 the summit crater of Nyiragongo volcano, located in the Great Lakes region of central Africa, began to fill with new lava, ending nearly 12 years of quiescence. An earlier eruption of the volcano in 1977 had culminated in the catastrophic draining of a lava lake through fissures in the crater wall, feeding highly mobile lava flows which reached the outskirts of Goma and killed more than 70 people. By July 1994, as many as 20,000 Hutu refugees were arriving in Goma every hour, only 18km south from the summit of Nyiragongo. The exodus brought more than one million people to the camps near the town raising fears of a repeat of the 1977 eruption. This paper examines the role that satellite remote sensing could have played in surveillance of the volcano during this time, and demonstrates the potential for monitoring this and other volcanoes in the future. Images recorded by the spaceborne Advanced Very High Resolution Radiometer (AVHRR) – freely available over the Internet – provide semi-quantitative information on the activity of the volcano. The aim of this paper is to promote the wider use of readily available technologies.     

关于台站形变应变长条观测仪器的技术改造及建议

指出了台站形变、应变长条观测仪器存在的问题 ;介绍了“九五”期间对之进行的技术改造及其收效。同时 ,对“十五”在这个项目上应进行的技术改造提出了建设性意见。     

ASSESSING ENVIRONMENTAL EFFECTS OF SEVERE SUSTAINED DROUGHT1

ABSTRACT: Evaluation criteria for reservoir and stream resources were developed to provide decision makers with feedback on environmental consequences of water allocation decisions under conditions of severe sustained drought within the Colorado River Basin by using the AZCOL gaming simulation model. Seven categories of flow dependent resources were identified which highlight resource states associated with reservoirs or river reaches within the AZCOL model. AZCOL directly simulates impact of water management decisions on five resource categories: threatened, endangered or sensitive fish; native nonlisted fish; wetland and riparian elements; national or state wildlife refuges; and hatcheries or other flow dependent facilities. Two additional categories - cold and warm water sport fish - are not modeled explicitly but are incorporated in the evaluation of monetary benefits from recreation on Colorado River waters. Each resource category was characterized at each time step in the simulation according to one of four environmental states: stable, threatened, endangered, or extirpated. Changes in resource states were modeled by time and flow-dependent decision criteria tied to either reservoir level or stream flows within the AZCOL model structure. Gaming results using the AZCOL model indicate environmental impacts would be substantial and that water allocation decisions directly impacted environmental resource states.