Distribution patterns of the ghost crab Ocypode cursor on sandy beaches of a tropical island in the Cabo Verde archipelago,Eastern Central Atlantic     

E Rodrigues  R Freitas  N de C Delgado 《African Journal of Marine Science》2016,38(2):181-188

The spatial distribution of the ghost crab Ocypode cursor was determined for beaches on eastern Boa Vista Island, Cabo Verde Archipelago. The main objectives were to analyse the across-shore distribution by means of burrow counts and to identify preferential zones and spatial segregation. Six beaches were investigated using 20 across-shore beach transects. It was demonstrated that ghost crabs occur throughout the entire intertidal zone, with higher densities in a 9–13 m band above the waterline. There was an exponential relationship between the carapace length of captured crabs and the diameter of their burrows. Mean burrow diameter was correlated with burrow density and increased linearly with distance from the waterline, although small burrows, representing individuals smaller than the median size, occurred across the beach. Burrow diameter and depth were positively correlated, with larger holes indicating larger crabs and deeper burrows. Deeper burrows were more common in the upper intertidal zone. These results are similar to those described for ghost crab populations elsewhere and contribute to an understanding of the ecology of the species in the local context.  相似文献   

A vessel‐deployed passive postlarval collector to assess settlement of the American lobster Homarus americanus     

Richard A. Wahle  Carl Wilson  Matthew Parkhurst  Charlene E. Bergeron 《新西兰海洋与淡水研究杂志》2013,47(1):465-474

Passive collectors are used widely in postlarval settlement and recruitment monitoring of spiny lobsters and crabs, but they have only been used in a limited way with clawed lobsters. For nearly two decades, diver‐based suction sampling has served to monitor spatial‐temporal patterns of American lobster (Homarus americanus) postlarval settlement and early juvenile abundance in shallow near‐shore nurseries. Collectors could reveal settlement patterns in zones beyond the practical limits of diving. In 2005, we launched a fisher‐scientist collaboration to evaluate the performance of passive collectors designed to extend the reach of sampling, and to be deployable from a vessel equipped with a standard pot‐hauler. Building on previous designs, our collectors comprised wire mesh trays lined with fine screening on the floor and walls and filled with cobble to simulate natural nursery habitat. Results indicate that no newly settled lobsters were lost during the retrieval process, and densities of young‐of‐year lobsters found in the collectors were similar to those in directly adjacent natural cobble habitat sampled by divers with suction samplers. The collectors also proved to be effective samplers of juvenile fish and crabs, suggesting a possibility for wider application. This success bodes well for expanded deployment of cobble collectors to broaden our understanding of the recruitment processes of lobster and other cobble‐dwelling fauna along the coast of New England, United States and Atlantic Canada.  相似文献   

巢湖流域双桥河底泥疏浚对浮游甲壳动物群落结构的影响     

丁瑞睿  郭匿春  马友华 《湖泊科学》2019,31(3):714-723

为研究河流底泥疏浚工程对富营养化河流水生生态系统的影响,选取巢湖双桥河开展为期一年的河流生态监测与调查,对比分析了巢湖双桥河疏浚前和疏浚后的水质指标、浮游甲壳动物群落结构及生物多样性指数.研究发现：底泥疏浚后双桥河水质得到明显改善,其中氮、磷营养盐分别削减48.09%和19.09%;底泥疏浚对浮游甲壳动物群落结构影响显著,疏浚后浮游甲壳动物生物量从1.86 mg/L下降到0.25 mg/L,下降了86.40%;疏浚后生物多样性指数高于疏浚前,且受季节影响较大;浮游甲壳动物与水环境因子相关性研究发现：pH、温度、铵态氮、硝态氮、可溶性氮、总氮和氮磷比对浮游甲壳动物总生物量均有极显著影响.研究结果表明,河流底泥疏浚工程能显著削减水体中氮、磷营养盐,并从一定程度上改善河流浮游甲壳动物群落结构,促进河流水生生态系统向健康、安全的方向发展.因此,对于双桥河这种受城市外源污染影响较大的城市污染型河流,在削减外源营养盐特别是氮输入的条件下,实施底泥疏浚工程可以促进其水生生态系统的修复.  相似文献   

十足类甲壳动物多倍体育种进展   总被引：5，自引：1，他引：4  

袁保京  姜乃澄 《海洋学研究》1998,16(4):64-67

结合作者近期的研究,综述了近年来十足类甲壳动物多倍体育种的原理及诱导方法的进展,并对研究现状、存在问题和今后的发展方向进行了探讨。  相似文献   

十足类甲壳动物精子发生过程中细胞器变化及作用研究进展     

杨万喜 《海洋学研究》1998,16(4):52-56

结合作者的研究,综述了近年来甲壳动物精子发生的细胞学研究进展,对高尔基体、线粒体、内质网、中心体及溶酶体等几种主要细胞器在精子发生中的作用作了分析,并就目前研究的现状,提出了今后的研究方向。  相似文献   

The transcription of iodothyronine deiodinase genes is regulated by thyroid hormone receptor in the Pacific oyster Crassostrea gigas     

HUANG Wen  XU Fei  LI Li  QUE Huayong  ZHANG Guofan 《海洋湖沼学报（英文）》2019,(4):1317-1323

  相似文献   

条斑紫菜脱落酸合成对高盐胁迫的响应及其对光合作用的保护     

余斌  杨佳丽  牛建峰  王广策 《海洋科学》2018,42(11):83-90

植物在逆境下产生活性氧,诱导抗氧化酶活性、抗逆基因表达上调。采用梯度盐度胁迫的方法处理条斑紫菜,发现高盐胁迫下细胞内脱落酸(ABA)含量随盐度的增加而增加,提示条斑紫菜中可能存在ABA介导的抗氧化代谢通路。利用ABA间接合成途径相关的几种抑制剂处理条斑紫菜叶状体,高盐胁迫诱导氧自由基产生,在藻体复苏过程中通过测定光合作用参数的恢复情况,探测藻体受到的氧化伤害,从而证明条斑紫菜中ABA生物合成的可能路径。结果显示多效唑显著降低了光系统II的电子传递能力,说明条斑紫菜中C5前体的合成是通过类似真菌的MVA途径;萘普生减缓了光合参数的恢复,说明条斑紫菜中ABA合成途径类似于类胡萝卜素参与的间接途径;然而,间接途径合成最后一步的抑制剂钨酸钠却没有影响条斑紫菜胁迫后光合作用参数的恢复,说明条斑紫菜中可能存在经由脱落醇生成ABA的支路途径,而脱落醇可作为活性分子,调控抗氧化酶的表达。烯唑醇则可能引起ABA的分解代谢受到抑制,导致过氧化氢的过度产生,并最终对机体产生不利影响。本文的结果为后续条斑紫菜ABA介导的抗氧化机制解析提供了数据支持。  相似文献   

Synergistic effect of extreme climatic events and urbanization on population density of the ghost crab Ocypode quadrata (Fabricius, 1787)     

Phillipe M. Machado  Davi C. Tavares  Ilana R. Zalmon 《Marine Ecology》2019,40(2)

The combined effects of urbanization and extreme climatic events were examined on the ghost crab Ocypode quadrata, a well‐recognized ecological indicator in sandy beaches. The effect of storm waves was assessed before and after these climate events in beaches with different levels of urbanization in the coast of Brazil, Tropical Atlantic Ocean. The number of burrows was used as a metric for the population size of O. quadrata and the number of humans along the beaches as a proxy for the urbanization level. Significant differences were recorded in this species’ population density according to the human pressure. Our core modelling approach showed that the number of O. quadrata burrows was lower after storm waves in urbanized zones, compared to non‐urbanized ones. The interaction between storm waves and urbanization impacted the number of O. quadrata burrows negatively, and suggest that species’ populations are more vulnerable to the combined effects of extreme climatic events and urbanization. Extreme events are predicted to increase in frequency in the next few decades, and may modify or impair ecosystem functioning in sandy beaches by reducing populations of the O. quadrata, an important beach scavenger, which markedly contribute to the flux of energy in coastal trophic webs.  相似文献   

无鱼粉日粮条件下黄颡鱼生长性能和肝胰脏转录组差异表达的研究     

周露阳  叶元土  蔡春芳  吴萍  高敏敏  郁浓  孙飞  吕昊  石瑶瑶  吕斌  易皓明 《海洋科学》2019,43(12):97-109

本研究以黄颡鱼(Pelteobagrus fulvidraco)为试验对象,设计两种饲料:鱼粉组和无鱼粉组,在池塘网箱中投喂70 d,研究其生长性能和肝胰脏转录组表达的差异。同鱼粉组相比,无鱼粉组黄颡鱼特定生长率下降了30.25%(P0.05),饲料系数显著增加了83.94%(P0.05),全鱼脂肪含量显著下降(P0.05),血清甘油三酯含量显著下降(P0.05),血清转氨酶活力显著增加(P0.05)。肝胰脏转录组结果显示,总计有12 020个基因差异表达,其中差异表达上调的基因有5 020个、差异表达下调的基因有7 000个。同鱼粉组相比,无鱼粉组分别有1 013个基因表达显著上调、2749基因表达显著下调(P0.05)。将组间具有差异表达的基因进行GO Term、KEGG pathway分类,结果显示:无鱼粉组的肝胰脏细胞组成、细胞生物过程、细胞分子功能等绝大多数基因差异表达下调,提示肝胰脏的细胞组织结构和功能受到很大的影响;KEGG通路富集到15个显著差异代谢通路。本研究结果表明,日粮中鱼粉可能含有某些生理活性物质,这些物质以神经分泌、激素调控、代谢信号通路等为作用靶点,通过对这些代谢信号通路的调节,对鱼的整体生理代谢强度、细胞结构与功能、生理健康状态等产生明显积极促进影响。缺乏这些物质则会造成黄颡鱼生长性能下降、部分器官组织细胞(肝细胞、神经轴突)受到损伤、鱼体抗应激能力和免疫防御能力下降。  相似文献   

黄鳝血清甲状腺激素的检测与分析     

邹记兴 《广东海洋大学学报》1999,(3)

用放射免疫测定法测定了４４ 条不同性别黄鳝（Ｍｏｎｏｐｔｅｒｕｓ ａｌｂｕｓ Ｚｕｉｅｗ ）血清总甲状腺激素Ｔｈｙｒｏｘｉｎｅ Ｔ３,Ｔｒｉｉｏｄｏｔｈｙｒｏｎｉｎｅ Ｔ４）含量。结果表明：（１）５～９ 月雄性Ｔ３ 含量一直较高;雌性５～６ 月Ｔ３含量比雄性和兼性低,７ 月以后升至与兼性持平,８～９ 月达到与雄性持平,高于兼性含量,升幅较大,但差异不显著（Ｐ＞ ０．０５）。（２）５～６ 月雄性Ｔ４ 含量稍高于其它性别,７ 月以后有所降低;雌性与兼性 Ｔ４ 含量与变化趋势基本相同。（３）同性别Ｔ４ 含量比Ｔ３ 含量要低得多。甲状腺激素可能与性逆转关系不大,其作用在于促进代谢与生长。  相似文献