水利隐患GPR探测方法研究

结合对堤专各类隐患探测实践与效果,从堤专外在条件下内部性质特点,联系各种隐患自身性质、特点及其与外部条件之间的关系、差异等因素,探讨利用地雷达（ＧＰＲ）探测各类隐患的探测方法与要求。     

Spatiotemporal distribution of protozooplankton and copepod nauplii in relation to the occurrence of giant jellyfish in the Yellow Sea

The occurrence of the giant jellyfish, Nemopilema nomurai, has been a frequent phenomenon in the Yellow Sea. However, the relationship between the giant jellyfish and protozoa, in particular ciliates, remains largely unknown. We investigated the distribution of nanoflagellates, ciliates, Noctiluca scintillans, and copepod nauplii along the transect 33~N in the Yellow Sea in June and August, 2012, during an occurrence of the giant jellyfish, and in October of that year when the jellyfish was absent. The organisms studied were mainly concentrated in the surface waters in summer, while in autumn they were evenly distributed in the water column. Nanoflagellate, ciliate, and copepod nauplii biomasses increased from early June to August along with jellyfish growth, the first two decreased in October, while N. scintillans biomass peaked in early June to 3 571 pg C/L and decreased in August and October. In summer, ciliate biomass greatly exceeded that of copepod nauplii （4.61-15.04 ~tg C/L vs. 0.34-0.89 pg C/L）. Ciliate production was even more important than biomass, ranging from 6.59 to 34.19 ~tg C/（L.d） in summer. Our data suggest a tight and positive association among the nano-, micro-, and meso-zooplankton in the study area. Statistical analysis revealed that the abundance and total production of ciliate as well as loricate ciliate biomass were positively correlated with giant jellyfish biomass, indicating a possible predator-prey relationship between ciliates and giant jellyfish. This is in contrast to a previous study, which reported a significant reduction in ciliate standing crops due to the mass occurrence ofN. nomurai in summer. Our study indicates that, with its high biomass and, in particular, high production ciliates might support the mass occurrence of giant jellyfish.     

山西灵丘苍鹭集群营巢繁殖地初步调查

<正>苍鹭Ardea cinerea,鸟纲(Aves),鹳形目(Ciconiiformes),鹭科(Ardeidae),鹭属Ardeaherodias,大型水边鸟类,头、颈、脚和嘴均甚长,成鸟雄性体长约75～110cm,雌性75～100cm,雄鸟头顶中央和颈白色,头顶两侧和枕部黑色,由4根细长的羽毛向后形成羽     

芦苇湿地共域繁殖的4种雀形目鸟类的巢址选择和繁殖成效比较

鸟类的巢址选择对其繁殖成效具有重要影响。对共域繁殖的不同鸟种繁殖策略的比较,有助于理解鸟类生活史对策的进化。为此,我们在河北永年洼湿地对利用芦苇繁殖的4种鸟类即东方大苇莺(Acrocephalus orientalis)、钝翅苇莺(Acrocephalus concinens)、震旦鸦雀(Paradoxornis heudei)和棕头鸦雀(Sinosuthora webbiana)的巢址选择和繁殖成效进行了比较。结果表明,尽管四种鸟类开始繁殖的时间明显不同,但其巢址、巢型和巢结构均类似,并在同一研究地内镶嵌分布,仅在巢离水面的高度、筑巢芦苇的高度和巢址样方内的芦苇密度三个变量参数上存在显著差异。四种鸟类在两个繁殖季的繁殖成效均较低,其中东方大苇莺为34.5%(86/249),钝翅苇莺为35.3%(6/17),震旦鸦雀为38.5%(15/39),棕头鸦雀为40.9%(9/22)。影响繁殖成效的主要生态因子包括巢捕食和恶劣天气如暴雨和强风暴,而被大杜鹃(Cuculuscanorus)寄生则是导致东方大苇莺繁殖成功率较低的主要原因。我们的研究表明,同域繁殖的鸟类可以通过繁殖时间的错峰和巢址的分化等而实现共存。     

曼氏无针乌贼(Sepiella japonica)繁殖期行为谱特征的研究

自然海域中曼氏无针乌贼产卵亲体性成熟提前和小型化现象明显，这可能是一种适应性进化，人工干预背景下曼氏无针乌贼繁殖期行为的动态变化值得关注。2020年4-6月室内采用聚焦个体扫描法和定点连续记录法分别观察和记录了曼氏无针乌贼繁殖期的行为活动，并按其生活习性和行为的生物学功能等进行系统化分类，构建了繁殖期行为谱。结果表明，曼氏无针乌贼繁殖期行为谱主要包括三大类12种行为：（1）游泳行为主要分为前进和后退，繁殖期的雌性多处于静潜水底或静浮水中的状态；（2）捕食行为主要分为发现、定位、捕捉和咀嚼等系列动作，曼氏无针乌贼能够快速感知周围17.0-36.0 cm范围内的饵料，捕捉的有效距离为8.0-22.0 cm，能在2.0-10.0 s内完成对饵料的高效捕获；（3）繁殖行为复杂，主要分为求偶、伴游、交配、产卵等，其中求偶行为体现在雄性对雌性的自我展示、追逐配对和争斗护卫等过程，雄性在争斗护卫和伴游过程中的护雌行为尤为激烈。曼氏无针乌贼交配时采用"头对头"的方式，平均交配持续时间42.9 s。曼氏无针乌贼对产卵附着基有选择性且偏好于最初的附卵物，卵群对雌性产卵行为有诱导和刺激作用，每次产卵到附卵过程平均用时108.6 s。曼氏无针乌贼繁殖期行为谱特征的研究可为后续曼氏无针乌贼行为机制和基于全生活史的资源保护等方面提供理论依据。