甘肃永登雹云回波群体特性分析

本文用711测雨雷达实测的冰雹云过程回波资料,分析了大小回波在雹暴形成中的演变过程以及回波强度和回波高度间的关系.结果表明永登防雹试验区回波覆盖面积比最大频数时为3.64%,平均为7%,回波块数最大频数为6块,平均为6块;回波覆盖面积比与雹日的月际变化呈正相关,回波块数与雹日的月际变化呈负相关;回波厚度在识别雹云中有重要意义.     

顺层滑坡的发育环境及分布特征

顺层坡是山区铁路、公路和水利水电工程建设中常见的一类斜坡，也是极易失稳滑动的一类斜坡，其稳定性及其影响因素一直是工程技术人员关心的问题。在现场勘测和调查的基础上，对涪陵市至酉阳县龙潭镇渝怀铁路沿线顺层滑坡的发育环境及其分布特征进行了系统的统计分析，结果表明：岩层中的软弱夹层、构造变动时形成的层间错动面及因河流切割而形成的有效临空面是顺层滑坡发育的基本条件；暴雨是斜坡滑动的重要诱发因素；滑坡发育程度随坡高的增大而增大，随岩层走向与斜坡临空面走向间夹角的增大而减小，同时具有凸形坡大于直线坡而直线坡大于凹形坡的规律。     

辽宁酷热日的天气气候分析

利用统计方法对辽宁1951-2003年的酷热天气进行了分析,发现辽宁的酷热天气主要出现在辽西地区;酷热天气在5-7月均可出现,主要集中在7月;无明显的年际变化.中纬度东-西高压带是造成辽宁酷热天气的主要天气形势;其次是西风带暖高压,在850hPa温度场上,辽宁西部在24℃暖中心之内有很好的指示意义.     

共基质条件下TNT降解菌的选育及其处理效果

选取SBR弹药销毁废水处理系统中的活性污泥作为菌源,在共基质条件下,经过驯化和筛选,分离出11株可降解TNT的单菌,从中选出生长速度较快的3株菌JT1,JT2,JT3进行了单菌及混菌降解能力测试,结果表明:混合菌JTH降解能力最强,其适宜环境条件为25℃～30℃,pH7.5～9.0,基质中添加2g/L葡萄糖可显著增强混菌JTH生长并可使24h内的TNT降解率达到96 1%;模拟废水的处理实验表明:混菌JTH对COD的去除率>80%,TNT降解率80%～90%;生物强化实验表明:以0.1的菌量污泥比在SBR系统中投加混合菌可使系统的出水COD稳定在100mg/L左右,出水TNT浓度<5mg/L。     

Watershed Management and Organizational Dynamics: Nationwide Findings and Regional Variation

Recent attention has focused on resource management initiatives at the watershed scale with emphasis on collaborative, locally driven, and decentralized institutional arrangements. Existing literature on limited selections of well-established watershed-based organizations has provided valuable insights. The current research extends this focus by including a broad survey of watershed organizations from across the United States as a means to estimate a national portrait. Organizational characteristics include year of formation, membership size and composition, budget, guiding principles, and mechanisms of decision-making. These characteristics and the issue concerns of organizations are expected to vary with respect to location. Because this research focuses on organizations that are place based and stakeholder driven, the forces driving them are expected to differ across regions of the country. On this basis of location, we suggest basic elements for a regional assessment of watershed organizations to channel future research and to better approximate the organizational dynamics, issue concerns, and information needs unique to organizations across the country. At the broadest level, the identification of regional patterns or organizational similarities may facilitate the linkage among organizations to coordinate their actions at the much broader river basin or ecosystem scale.     

青海高原地震重灾区的灾害特点及成因探析

本文运用1950～2003年53年间青海高原地震主发区5.0级以上(包括5.0级)地震资料分析了该区地震灾害的特点.提出本研究区地震灾害具有频发性和轮回性、重灾轮回的时间周期长、强震的毁坏性大、以及强余震灾害连发而损害程度严重等特点,并认为青藏高原整体地壳构造运动和本区断裂构造十分发育(特别是北西西-北西向弧形断裂的发育)是该区地震灾害重发的主要原因.     

The Ecological and Environmental Characteristics and Conservation of the Wetlands in the Changjiang Estuary, China

The natural wetlands in the Changjiang Estuary, China are important ecologically. The total area of the wetlands in the Changjiang Estuary amounts to 215000 ha. The wetlands consist of littoral and sandy estuarine island areas, and are rich in biological resources. There are 136 species of vascular plant, 150 species of bird, and 68 species of benthic macro-invertebrate in the wetlands. However, the wetland in the Changjiang Estuary is a vulnerable ecosystem. Development of the wetland is mainly influenced by intensive human reclamation, pollution, movement of sediments in the Changjiang River, and the effects of tides and waves. Investigations have shown that maintaining biodiversity, providing resources for the living organisms, purifying environments and resisting natural hazards could be regarded as important functions for the protection of the wetlands. It is proposed that sustainable principles should be supported in developing the wetlands in the future.     

关于中国塔里木河流域若干问题的辨识

塔里木河流域的水量及水质变化 ,生态环境质量的优劣 ,生态需水量的估算、整治目标的确定等问题 ,一直是该流域资源环境和社会经济的核心问题。对其近 40年来水文观测资料的时间序列进行分析 ,三源流区的水资源量逐年递增 2× 1 0 7m3,但干流上游阿拉尔来水量每年递减 3× 1 0 7m3。水质的劣变特征亦较明显。通过构建生态脆弱性指数 ,定量评价流域生态环境质量表明 ,干流下游已属于生态环境严重受损区。用潜水蒸发和定额法的原理估算植被耗水 ,提出了维护干流区生态环境在不同目标年的生态需水量。认为应当在水资源承载力和环境容量的阈限内 ,合理确定科学的保护方案     

红厚壳在海南岛的分布及其生长习性

红厚壳在海南岛一直是适应性强，分布广泛的珍贵植物资源。调查结果表明，在经济建设，农业土地开发等压力下，海南岛的红厚壳植物资源正日趋减少，目前仅在琼山，文昌等地区还保留较丰富，南部地区已绝迹，西部地区也难以见到。     

青海野生大黄的生态特征及其开发对策

文章通过对青海野生大黄的生态环境、分布状况、群落特征、开发现状、存在问题的分析和论述，提出未来青海野生大黄资源开发必须遵从生态保护为先，生态、生产、经济、社会效益共同持续的原则，强化资源保护和基础技术研究，加大人工驯化裁培力度，不断满足日益增长的市场需求。