常绿树种在昆明市园林绿地系统中的应用

基于对昆明市区代表性的几大绿地类型中常绿树种应用现状的实地调查,从该市绿地系统树种选择和植物配置两方面进行综合分析,指出昆明市常绿树种应用中存在的问题并提出相应的改进措施,以充分发挥常绿树种在城市绿地系统中绿化,美化和改善环境方面的功能并分体现昆明“春城”与整个云南“植物王国”的特色。     

大扁杏的栽培管理技术

北山大扁杏是我国"三北"地区特有的经济树种之一,经济价值高,它具有适应性强、生长快、结果早等特点。结合近几年来大扁杏管理和生产实践经验,总结出了大扁杏的优质丰产栽培管理技术。通过对大扁杏园的建立,规范的土壤管理以及施肥、灌溉、整形修剪技术的介绍,归纳出了大扁杏科学的栽培管理技术对提高大扁杏质量和产量具有重要意义。     

防治谷蠹的含有植物精油的植物种类及植物精油对谷蠹作用方式的研究现状

谷蠹是一种世界性分布害虫,能够引起粮食的巨大损失。由于化学杀虫剂对环境和人畜安全存在巨大威胁,加上谷蠹抗药性的不断发展,植物精油作为一类植物性杀虫物质,来源于自然界,取材广泛,在环境中残留较少,不污染粮食,害虫不易产生抗药性,具有广阔的发展前景。因此本文对防治谷蠹的含有植物精油的植物种类和植物精油对谷蠹的作用方式进行了综述。     

Modelling the distribution of the pan‐continental invasive fish Pseudorasbora parva based on landscape features in the northern Kyushu Island,Japan

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我国渔业新技术、新品种引进现状及发展战略研究

建国以来,我国的渔业新技术、水产养殖新品种引进工作取得了令人注目的成就,先报引进各类渔业新技术及动、植物新品种上百项;为促进我国的水产事业发展做出了积极的贡献。本文简要总结、回顾了我国渔业新技术及水产养殖新品种引进工作的现状,找出了存在的主要问题,并对今后工作提出了一些建议,以供有关部门决策参考。     

Using acoustic telemetry and snorkel surveys to study diel activity and seasonal migration of round goby (Neogobius melanostomus) in an estuary of the Western Baltic Sea

In just two decades, round goby Neogobius melanostomus (Pallas) has dispersed throughout most of the Baltic and the North American Great Lakes. It thrives in shallow sheltered areas, where it is impacting native fauna. In Denmark, researchers, governmental institutions and fishers have joined in an effort to establish a sustainable round goby fishery. To do so, basic information about the movement of round goby is essential, so the movements of 50 round gobies were tracked using acoustic telemetry. The results revealed that activity took place mainly at night and seasonal migrations were common. The most frequent migration behaviour observed was a seaward return migration during winter, which was further confirmed by a snorkel survey. Tracking data also revealed riverine upstream dispersal. The results demonstrate that the round goby can be mapped using telemetry, and it is suggested that fishing for round goby may improve efficiency by targeting seasonal migration corridors.     

Detecting the undetectable: Characterization,optimization, and validation of an eDNA detection assay for the federally endangered dwarf wedgemussel,Alasmidonta heterodon (Bivalvia: Unionoida)

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Looking beyond the horizon: An early warning system to keep marine mammal information relevant for conservation

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Limaria hians (Mollusca: Limacea): a neglected reef‐forming keystone species

1. The case is made for recognition of the marine bivalve Limaria hians as a reef‐forming species, which plays a key architectural role in certain benthic communities around the United Kingdom and Ireland. 2. This species uses byssal threads to construct nests that can coalesce to form reefs that cover hectares of seabed, contain multiple conspecifics and bind sediment. In so doing, L. hians modifies physical, chemical and biological processes at the sediment–water interface. 3. Such nests support a high diversity of associated organisms in coarse‐grade sediments (19 species of algae and 265 species of invertebrates from six discrete nests in Loch Fyne are reported on), although the biological interactions between species both inside and outside this assemblage (e.g. predatory cod) are unknown. 4. Being insubstantial, labyrinthine structures situated on the sediment surface, Limaria nests are sensitive to mechanical impacts, such as those caused by moorings, hydraulic dredging for infaunal bivalves and scallop dredging. 5. At appropriate sites, the status of L. hians can contribute a useful indication of disturbance on coarse‐grade sediments. Copyright © 2000 John Wiley & Sons, Ltd.     

A rapid screening technique for drought resistance in potato (Solanum tuberosum L.)

Summary The reduction in growth in the dark of leaf dises floated over polyethylene glycol 6000 solution of water potential −0.4 MPa, relative to the growth of similar leaf dises floated over water for the same period, varied in the range 10–87% in 28 genotypes. The growth reductions in the genotypes tested were in general agreement with what is known about their drought resistance. Publication No. 906, Central Potato Research Institute, Simla.