海岸带生态恢复技术研究现状及存在问题

气候及其潜在的全球性变化所带来的影响，使海岸带受到严重威胁，人口的增加以及人类活动强度的增大给海岸带环境带来的负面影响越来越严重，对目前国内外海岸带生态恢复技术的现状作了较系统地介绍，并阐述了当前海岸带生态恢复中存在的主要问题。     

黄土高原沙棘灌丛资源保护和发展问题

沙棘适合于在干旱瘠溥的黄土高原地区生长，在黄土高原生态恢复、环境治理和经济发展中成效显著，近年来沙棘灌丛资源发展迅速。但由于在沙棘灌丛资源保护和发展中还存在不少问题，使黄土高原区域整体效益并不理想。文章研究了黄土高原地区沙棘灌丛资源的类型，共有6个群系；分析了黄土高原沙棘灌丛资源的现状和效益，其在工矿废弃地治理、砒砂岩区治理、沙化土地治理、水土保持等方面作用明显，对当地畜牧业、食品工业、医药业起到促进作用；探讨了存在的主要问题，一是资源发展问题，二是保护问题，三是管理问题，四是科学技术问题；最后从多个方面提出了黄土高原沙棘灌丛资源保护与发展的对策，     

Variation in populations of the coastal dune building grassLeymus arenarius in Iceland revealed by endospermal prolamins

Variation in the endospermal protein patterns of seeds amongst and between inland and coastal populations of the dune building grassLeymus arenarius was examined in Iceland. Seeds were collected from six coastal populations and five inland populations in Iceland. Endospermal proteins (prolamins) of seeds were extracted with Tris-buffered 2-propanol (50%) and β-mercaptoethanol (0.5% v/v). We used 8% and 12% sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) to separate the prolamin protein bands, which were stained with Coomassie Brilliant Blue R. Coastal populations were differentiated from inland populations on the basis of high frequency of high molar weight (HMW) (110–150 kg mol⁻¹) prolamins. Coastal populations had significantly higher proportions of their seed with more than two HMW prolamins, than those of inland populations. Subtle differences were found among the HMW prolamins of coastal and inland populations indicating limited intrapopulation variation. The dynamic environment of sand dunes probably influences the genetic composition of these populations. The results suggest that seeds of the inland and coastal populations should be treated separately in sand dune reclamation and restoration works     

沉水植物黑藻对沉积物氨氮吸附/释放特征的影响

氮素是主要的湖泊营养盐,而沉水植物作为湖泊生态系统主要的组成部分,对系统中氮素的跨界面迁移有着重要的影响。在实验室模拟条件下,通过沉积物氨氮释放动力学、吸附热力学和吸附动力学实验,研究了沉水植物黑藻(Hydrilla verticilla)对沉积物氨氮吸附/释放特征的影响,得到如下结论:(1)一级动力学反应模型能较好地拟合沉积物氨氮释放的动力学过程,种植沉水植物没有影响氨氮释放的趋势,但增强了沉积物释放氨氮的能力;(2)分别用多个模型对沉积物氨氮吸附热力学和动力学过程进行拟合,结果均表明种植沉水植物以后,沉积物对氨氮吸附的趋势没有影响,但吸附强度有所下降。     

水生态修复对莲花湖底栖动物群落的影响

武汉莲花湖是典型的富营养化城市浅水湖泊．通过对其进行16mo的监测后发现，治理后的小莲花湖比大莲花湖水质有明显改善．监测期间小莲花湖底栖动物密度和生物量均值明显高于大莲花湖，Shannon多样性指数与Margalef多样性指数也高于大莲花湖．将大、小莲花湖的10种环境因子和底栖动物密度进行典型相关分析后，发现总磷、温度、总氮、叶绿素a、氨离子是对底栖动物群落具有显著性影响的环境因子．图8表3参20.     

天然水体中有机酸当量浓度的确定方法

本文根据天然水体中溶解有机在碳与化学需氧量和生化需氧量之间的相关性，以及有机酸当量和水体溶解有机碳之间的近似定量关系，提出了由化学需氧量或生化需氧量得到溶解有机碳或总有机碳浓度，最终得到有机酸和有机酸根当量浓度的转换方法，为大区域天然水体有机酸碱缓冲作用的评估提供了一个实用的转换途径。     

Structure and function of the eversible glands of the aquatic firefly <Emphasis Type="Italic">Luciola leii</Emphasis> (Coleoptera: Lampyridae)

Summary. When attacked or otherwise disturbed, larvae of the aquatic firefly Luciola leii display fork-shaped glands laterally from the meso- and metathorax as well as each abdominal segment. Glandular eversion is accompanied by a strong pine oil-like odour, thanatosis and glowing from paired larval light organs. Observations by SEM and TEM revealed that there are numerous, almost spherical protuberances, measuring 9 μm in diameter on the surface of each gland. Each protuberance is connected to a well developed secretory cell via a 0.1 μm thick and 0.2 μm long stalk and bears three to six 7 μm long spines on its apex. The convoluted glandular walls measure 0.2 μm. The cytoplasm of the secretory cells is characterized by the presence of numerous mitochondria and an extensive system of cisternae and tubular endoplasmic reticulum. Preliminary GC-MS analysis of the glandular secretion revealed two volatile terpenoids: terpinolene and γ-terpinene. Choice and no-choice bioassays involving fish and ants as well as other predators demonstrate that the secretions serve as an effective deterrent against a range of ecologically relevant enemies. The larval postural adjustments, light emission, everted glands, and glandular release of distasteful or repellent compounds, appear to function as a multi-modal, aposematic larval defence. The tandem evolution of glandular secretions and conspicuousness in larval fireflies could partially explain their successful radiation into both aquatic and terrestrial habitats.     

怀来盆地弃耕地自然恢复过程中土壤养分动态

研究了怀来盆地丘陵区弃耕地自然恢复过程中土壤养分的变化规律。采取空间代替时间的方法,确定了代表弃耕地初期阶段、草地阶段和灌丛地阶段的3种样地,通过分层取样测定了土壤有机质、全量养分和速效养分含量。结果表明,全量养分对生态系统恢复的响应与其相应的速效养分明显不同。随着弃耕地的恢复,土壤有机质有明显增加的趋势,P循环和K循环由物质控制向生物控制转换,但速效P在恢复初期增加缓慢。速效N由于耕种期施肥的影响表现出先降低而后增加的特点。全量养分中,只有全N在弃耕地自然恢复中有增加的趋势。灌丛可以在更深的层次上影响土壤养分。植被的恢复与土壤肥力的提高密切相关,这种作用随着植被的恢复而不断增强。