大型水母迁移规律和灾害监测预警技术研究进展

20世纪80年代以来,全球大型水母灾害发生频率与成灾种类不断增加,已严重影响了近海海洋渔业、沿海工业、滨海旅游业和海洋生态系统,已引起了各国政府高度重视,并且越来越多海洋工作者投身水母迁移等科学研究和监测预警工作中。回顾近年来国内外学者对水母漂移聚集和溯源等迁移规律的研究进展以及水母灾害监测预警工作现状。水母研究为预测预警工作服务,应侧重于开展系统的水母海上和室内试验,建立业务化立体监测体系;加强水母漂移聚集机理研究,建立更完善的水母预警模式。     

被动声学监测技术在陆生哺乳动物研究中的应用、进展和展望

被动声学监测(passive acoustic monitoring,PAM)技术指将自动录音机安装在自然环境中收集野生动物及其所在环境的声音信号的监测方法。20世纪90年代以来,PAM技术陆续被应用于翼手目和灵长目等陆生哺乳动物的监测和研究,探究了陆生哺乳动物行为学、生态学和保护生物学等方面的科学问题。然而,当前缺乏对这些研究的系统性总结和展望。本文从活动规律和时间分配、栖息地利用、物种分布、种群大小与密度、生物多样性、人为干扰的影响等领域综述了PAM技术在陆生哺乳动物中的研究进展,并列举了相关应用实例。总体上,PAM技术涉及到生物学、生态学、声学、计算机科学等多学科的交叉融合,其应用受限于声学数据的储存和管理、物种或个体自动化识别以及声学指数评估的普适性,设备价格也相对昂贵,这些可能是导致该技术在我国陆生哺乳动物监测和研究方面的应用还相对滞后于其他国家的原因。最后,本文对未来研究方向进行了展望,并建议尽快建立和完善我国陆生哺乳动物PAM网络和数据共享平台、组织开展面对面访问调查或生物多样性保护相关的知识竞赛等公民科学项目、向更多科研机构或保护区推广PAM技术的应用,使该技术成为陆生...     

声学指数在城市森林鸟类多样性评估中的应用

鸣声是鸟类之间进行沟通和传递信息的重要方式,这为通过声学监测评估鸟类多样性提供了独特的机会。利用声学指数快速评估生物多样性是一种新兴的调查方法,但城市森林中的复杂声环境可能会导致声学指数的指示结果出现偏差。为了解声学指数在城市森林中应用的可行性,本研究在北京市东郊森林公园设置了50个矩阵式调查样点,于2021年4–6月每月进行1次鸟类传统观测和同步鸣声采集,通过比较两种方法的结果来探究声学监测的有效性。采用Spearman相关分析和广义线性混合模型评估6个常用声学指数与鸟类丰富度和多度的关系,并衡量了每个指数的性能。结果表明:(1)本研究共记录到鸟类10目23科35种,通过声学监听识别的总物种数与传统鸟类观测相等,但具体鸟种存在差异;(2)不同月份间声学指数与鸟类丰富度和多度的相关性有明显差别,声学复杂度指数(ACI)和标准化声景差异指数(NDSI)优于其他指数,是评估鸟类多样性的关键变量;(3)声学指数对鸟类多度的预测能力(R²m=0.32,R2c=0.80)要高于丰富度(R²m=0.12,R2c=0.18)。声学指数为快速评估生物多样性提...     

现代生物声学的学科发展趋势及中国机遇

随着数字录音技术、电子学和微电子学、人工智能、信息科学等跨学科领域的技术革新,现代生物声学逐渐与生物学、生态学等学科及关联学科之间形成了广泛的交叉前沿领域。现阶段,现代生物声学主要以生物学、生态学等基础学科的理论方法为指导,着重于揭示环境中各类声音在生物之间以及生物与人类、环境之间的相互作用及相关科学规律,为人类认识、保护和利用生物声学资源提供理论基础和解决方案。本文重点阐述了现代生物声学的学科内涵和学科特征,介绍了动物生物声学、生态声学、水下生物声学、环境生物声学、保护生物声学、计算生物声学以及现代生物声学研究的技术框架等前沿热点和发展趋势,评估了中国生物声学研究的学科现状与发展机遇,并对未来学科建设进行了展望。     

草地螟的发生为害与监测预警技术研究进展

草地螟Loxostege sticticalis L.是我国北方农牧区重要的迁飞性害虫,具有突发性、暴发性和周期性危害的特点,随着第4个暴发周期的来临,将会给我国北方农牧业的安全生产带来很大的威胁.为准确掌握草地螟在我国的发生与迁飞为害规律,提高对重大迁飞性害虫的灾变预警能力,本文综述了草地螟在我国及周边国家的时空分布,发生为害、迁飞规律和监测预警等方面的研究进展,并对草地螟的监测预警技术进行了展望,以期为第4个暴发周期草地螟的监测和防控提供技术支持.     

基于环境DNA宏条形码技术的辽东湾典型围海养殖池塘内水母多样性研究

研究使用环境DNA宏条形码技术(eDNA metabarcoding)检测辽东湾东北部河口区围海养殖池塘水母种类多样性,探索适用于水母种类物种鉴定和监测的新方法。利用环境DNA宏条形码技术,分别基于18S rDNA和COI宏条形码检测了辽东湾东北部河口区围海养殖池塘水母种类多样性,通过水样采集、过滤、eDNA提取、遗传标记扩增、测序与生物信息分析的环境DNA宏条形码标准化分析流程,从围海养殖池塘7个采样点中获得可检测的采样点数据。结果显示,基于18S rDNA宏条形码检测出8种水母种类,其中钵水母纲大型水母2种、水螅水母总纲小型水母6种;基于COI宏条形码技术共检测出19种水母种类,其中钵水母纲大型水母5种、水螅水母总纲小型水母14种;两种DNA条形码标记都显示养殖种类海蜇(Rhopilema esculentum)为优势种。研究结果表明,环境DNA宏条形码技术作为一种新兴的生物多样性监测手段可用于快速检测水母种类多样性,在水母类物种鉴定、监测及早期预警中有较大的应用潜能。     

声景生态学研究进展和展望

声景生态学以景观中的声音为研究对象, 探讨其在不同时空维度上的分布和变化模式, 从而揭示自然环境、野生动物和人类活动的相互作用关系。本文通过系统检索声景生态学研究的相关文献, 回顾了该学科的研究框架和研究方法, 总结了目前常用的声学指标, 重点归纳了声景生态学的研究内容, 包括声景组成和各组分间的相互作用, 声景的时空格局, 以及声景生态学在生物多样性监测中的应用。目前, 声景监测中存在的问题主要包括监测的生态系统类型和物种类群有限、声学指标效力有待提高等。建议未来着重推进建立系统性的声景监测网络和数据管理平台, 开发和完善音频数据采集、分析方法和评估指标, 并重视声景数据的采集, 将声景视作一种资源进行研究和保护。     

我国农业害虫综合防治研究进展

农业害虫综合防治是昆虫学的一门应用科学,旨在明确农作物害虫的发生危害与暴发成灾规律,提出害虫监测预警和可持续治理的理论与方法。在2012-2016年的5年间,我国提出了基于生态系统服务和多尺度空间管理的害虫生态调控新理论,发展了害虫行为调控技术和化学防治新技术,并在棉铃虫对Bt棉花抗性治理对策、稻飞虱的监测预警和综合防控技术、小菜蛾抗药性诊断及治理技术、青藏高原农牧害虫发生规律和分区治理等防治实践中取得了重要进展。根据国际上害虫综合防治学科发展趋势和我国的研究现状,将来还需要在害虫灾变机制研究、害虫绿色防控技术创新研发以及集成应用等方面进行深入探索,为我国农业害虫可持续治理以及化学农药减量使用提供有力的科技支撑。     

Beta声学指数的特征和应用

随着录音设备性能的提高和硬件价格的降低,基于录音评估声景来反映生境特征和生物多样性的方法得到快速发展。声学指数是对声音整体特征的量化,受到录音生境和生物组成的共同影响,因此可构建声学指数与生境特征和生物组成的关联。按照作用的尺度,声学指数可分为两类:反映录音内信息的alpha声学指数和比较不同录音之间差异的beta声学指数。随着录音设备的普及,以及在大尺度上进行生物监测工作的增加,对不同时间、不同地点的录音进行比较的需求日益迫切。因此,beta声学指数的开发和应用是声学指数研究的重要方向。本文介绍了11个常用的beta声学指数,并探讨了这些指数的数学特征(非负性、同一性、对称性、直递性、有限性)。本文还通过文献检索获取了beta声学指数在实证中的应用情况,发现研究中常使用beta声学指数反映时间节律、生境特征的差异或生物组成的改变。最后,本文指出了beta声学指数研究/应用中迫切需要发展的3个方向:开发新的指数、优化已有指数的计算方式、增加实证研究。     

我国蝗虫暴发成灾的现状及其持续控制对策

概述并分析了我国蝗虫暴发成灾的现状及原因 ,认为全球气候变暖和区域性气候异常、人类活动的影响、监测预警技术手段落后、成灾蝗种增多和发生为害类型复杂、蝗虫研究队伍锐减及基础理论与高新技术研究滞后导致了近年来蝗虫的暴发成灾。对此 ,作者从蝗虫灾害的规律性、监测预警高新技术和综合治理技术等方面提出了实现蝗灾可持续控制的对策     

大型水母幼体生长的影响因子研究进展

21世纪以来,中国东、黄海,韩国西海岸以及日本海连年发生大型水母暴发现象,对海洋渔业的生产活动以及海洋生态系统带来巨大的影响。水母暴发形成机制非常复杂,解释其发生机理并有效预报是目前急待解决的问题。大型水母的生活史中有明显的世代交替现象,受精卵,浮浪幼虫,螅状体,足囊,横裂体到碟状体的幼体发育阶段属无性世代,幼蜇发育到成蜇阶段属有性世代。在早期生活史中,螅状体的足囊繁殖与横裂生殖是大型水母无性繁殖的重要方式,对其成体的数量形成至关重要。综述了国内外有关温度、盐度、光以及营养条件对大型水母早期发育阶段的影响研究进展,研究表明温度是影响螅状体发育以及足囊繁殖和横裂生殖的最主要的环境因子;盐度、光和营养条件在适温范围内,均对螅状体和横裂生殖有一定的影响,其上下限随水母种类和发育阶段有所变化。展望了大型水母早期幼体研究的发展趋势,如环境因子对不同种类的大型水母幼体生长机理的影响、多个环境因子对幼体的综合作用、动态的环境因子与大型水母幼体之间的关系等。     

Feeding capability of black scraper <Emphasis Type="Italic">Thamnaconus modestus</Emphasis> on giant jellyfish <Emphasis Type="Italic">Nemopilema nomurai</Emphasis> evaluated through field observations and tank experiments

Although many fish species are known to feed on jellyfish, only a few quantitative studies on this subject have been conducted in the field or laboratory. We combined field observations and feeding experiments to quantitatively evaluate the potential feeding capability of the black scraper Thamnaconus modestus on giant jellyfish Nemopilema nomurai in a jellyfish-abundant area. Underwater observations revealed that shoals of T. modestus fed voraciously on jellyfish when the jellyfish were close to the fish’s seaweed habitat. Gut contents of field-collected T. modestus almost exclusively consisted of jellyfish. In tank trials, feeding activity of black scraper was high when light intensity was between about 1.1 lx and 50 × 10³ lx. The estimated feeding speed of T. modestus on the jellyfish in the Sea of Japan when the jellyfish bloom occurred was 10.0 ± 2.0 times fish body weight per day. The results support the prediction that T. modestus and probably other coastal medusivorous fishes have a substantial capability to eliminate jellyfish blooms. Considering that they are highly dependent on seaweed bed, protection of such habitats for these medusivores may be the most cost-efficient control method for jellyfish blooms.     

Human forcing of the copepod–fish–jellyfish triangular trophic relationship

Copepods, the most abundant planktonic metazoans, constitute an intermediate trophic position between phytoplankton and higher trophic-level animals such as fish and jellyfish. Fish and jellyfish are adversaries because they often compete for prey copepods and also can be prey of each other. The classical food chain represented by phytoplankton–copepod–fish is the main process leading to efficient and sustainable production of fish as human food. At present, more than 75% of world fish stocks are fully or over exploited. On the other hand, jellyfish populations have increased world-wide, particularly in waters under significant human influences. Two such cases are seen in East Asian waters, where massive blooms of moon jellyfish (Aurelia aurita s.l.) and giant jellyfish (Nemopilema nomurai) have repeatedly occurred in recent decades, causing severe damage to local fisheries. In this article, I will review the pivotal role of copepods in marine ecosystems, particularly in the Inland Sea of Japan, where the annual fish catch per unit area is among the world’s highest. Then, I will describe an ongoing ecosystem shift from dominance by fish to dominance by jellyfish as a consequence of human forcing. Finally, I will propose to create “sato-umi”, a coastal sea with high productivity and biodiversity with wise human interaction, where copepod production would most efficiently transforms into food for humans.     

Analyzing Beach Recreationists’ Preferences for the Reduction of Jellyfish Blooms: Economic Results from a Stated-Choice Experiment in Catalonia,Spain

Jellyfish outbreaks and their consequences appear to be on the increase around the world, and are becoming particularly relevant in the Mediterranean. No previous studies have quantified tourism losses caused by jellyfish outbreaks. We used a stated-choice questionnaire and a Random Utility Model to estimate the amount of time respondents would be willing to add to their journey, in terms of reported extra travel time, in order to reduce the risk of encountering jellyfish blooms in the Catalan coast. The estimation results indicated that the respondents were willing to spend on average an additional 23.8% of their travel time to enjoy beach recreation in areas with a lower risk of jellyfish blooms. Using as a reference the opportunity cost of time, we found that the subsample of individuals who made a trade-off between the disutility generated by travelling longer in order to lower the risk of jellyfish blooms, and the utility gained from reducing this risk, are willing to pay on average €3.20 per beach visit. This estimate, combined with the respondents’ mean income, yielded annual economic gains associated with reduction of jellyfish blooms on the Catalan coast around €422.57 million, or about 11.95% of the tourism expenditures in 2012. From a policy-making perspective, this study confirms the importance of the economic impacts of jellyfish blooms and the need for mitigation strategies. In particular, providing daily information using social media applications or other technical devices may reduce these social costs. The current lack of knowledge about jellyfish suggests that providing this information to beach recreationists may be a substantially effective policy instrument for minimising the impact of jellyfish blooms.     

Greenhouse gas,upwelling‐favorable winds,and the future of coastal ocean upwelling ecosystems

Coastal ocean upwelling ecosystems generally represent the most productive large marine ecosystems of the world's oceans, in terms of both primary production rates and tonnages of exploitable fish produced. The Peruvian upwelling system, in particular, stands out as a major factor in world fish production. The Pacific trade winds have traditionally been considered to be the primary driving force for the upwelling system off Peru, but are projected to weaken as climate change proceeds. This leads to concern that the upwelling process in the Peru system, to which its productivity is linked, may likewise weaken. However, other mechanisms involving greenhouse‐associated intensification of thermal low‐pressure cells over the coastal landmasses of upwelling regions suggest general intensification of wind‐driven ocean upwelling in coastal upwelling regions of the world's oceans. But although certain empirical results have supported this expectation, it has not been consistently corroborated in climate model simulations, possibly because the scale of the coastal intensification may be small relative to the scales that are appropriately reflected in the standard models. Here we summarize available evidence for the intensification mechanism and present a proxy test that uses variations in water vapor, the dominant natural greenhouse gas, to offer multiple‐realization empirical evidence for action of the proposed mechanism in the real world situation. While many potential consequences to the future of marine ecosystems would codepend on climate change‐related changes in the thermocline and nutricline structures, an important subset, involving potential increased propensities for hypoxia, noxious gas eruptions, toxic red tide blooms, and/or jellyfish outbreaks, may depend more directly on changes in the upwelling‐favorable wind itself. A prospective role of fisheries in either mitigating or reinforcing this particular class of effects is suggested.     

Jellyfish modulate bacterial dynamic and community structure

Jellyfish blooms have increased in coastal areas around the world and the outbreaks have become longer and more frequent over the past few decades. The Mediterranean Sea is among the heavily affected regions and the common bloom-forming taxa are scyphozoans Aurelia aurita s.l., Pelagia noctiluca, and Rhizostoma pulmo. Jellyfish have few natural predators, therefore their carcasses at the termination of a bloom represent an organic-rich substrate that supports rapid bacterial growth, and may have a large impact on the surrounding environment. The focus of this study was to explore whether jellyfish substrate have an impact on bacterial community phylotype selection. We conducted in situ jellyfish-enrichment experiment with three different jellyfish species. Bacterial dynamic together with nutrients were monitored to assess decaying jellyfish-bacteria dynamics. Our results show that jellyfish biomass is characterized by protein rich organic matter, which is highly bioavailable to 'jellyfish-associated' and 'free-living' bacteria, and triggers rapid shifts in bacterial population dynamics and composition. Based on 16S rRNA clone libraries and denaturing gradient gel electrophoresis (DGGE) analysis, we observed a rapid shift in community composition from unculturable Alphaproteobacteria to culturable species of Gammaproteobacteria and Flavobacteria. The results of sequence analyses of bacterial isolates and of total bacterial community determined by culture independent genetic analysis showed the dominance of the Pseudoalteromonadaceae and the Vibrionaceae families. Elevated levels of dissolved proteins, dissolved organic and inorganic nutrient release, bacterial abundance and carbon production as well as ammonium concentrations characterized the degradation process. The biochemical composition of jellyfish species may influence changes in the amount of accumulated dissolved organic and inorganic nutrients. Our results can contribute insights into possible changes in bacterial population dynamics and nutrient pathways following jellyfish blooms which have important implications for ecology of coastal waters.     

Dynamic Model for Life History of Scyphozoa

A two-state life history model governed by ODEs is formulated to elucidate the population dynamics of jellyfish and to illuminate the triggering mechanism of its blooms. The polyp-medusa model admits trichotomous global dynamic scenarios: extinction, polyps survival only, and both survival. The population dynamics sensitively depend on several biotic and abiotic limiting factors such as substrate, temperature, and predation. The combination of temperature increase, substrate expansion, and predator diminishment acts synergistically to create a habitat that is more favorable for jellyfishes. Reducing artificial marine constructions, aiding predator populations, and directly controlling the jellyfish population would help to manage the jellyfish blooms. The theoretical analyses and numerical experiments yield several insights into the nature underlying the model and shed some new light on the general control strategy for jellyfish.     

水母旺发的诱因及对海洋环境的影响

水母旺发已成为一种新型海洋生态灾害,使海洋生态系统的结构和功能、海洋生态环境受到严重破坏.本文总结了水母旺发的可能诱因,重点探讨了水母旺发对海水生源要素、溶解氧、酸碱度以及生物群落的影响.结果表明: 水母旺发与其自身生理结构与生活史密切相关,其具有的身体结构简单、生长迅速、繁殖性强、世代间隔时间短及耐不良环境等特点,使其遇合适环境可迅速繁殖.水母旺发的主要直接诱因可能与海水温度变化有关,海水升温可导致水母食物增多,促进水母生殖,尤其对暖温性水母,更易引起水母聚集繁殖,形成旺发.富营养化、气候变化、过渡捕捞、生物入侵、栖息地改变也是水母旺发的重要影响因素.水母旺发可显著影响生源要素的形态和生物地球化学循环,水母排放NH₄⁺和PO₄^3-速率分别为59.1～91.5 μmol N·kg^-1·h^-1和1.1～1.8 μmol P·kg^-1·h^-1,可为浮游植物提供8%～10%和21.6%的N和P,释放溶解有机碳速率为1.0 μmol C·g^-1·d^-1.水母腐烂时总氮和总磷的释放速率可达4000 μmol N·kg^-1·d^-1和120 μmol P·kg^-1·d^-1,溶解有机碳的释放速率为30 μmol C·g^-1·d^-1;水母腐烂可影响水体的酸碱度与溶解氧含量,导致水体严重酸化与缺氧/无氧,pH降幅为1.3,平均耗氧量可达32.8 μmol·kg^-1·h^-1.水母旺发还可引起某些鱼类与浮游动物生物量的减少与重新分布,浮游微生物增加,间接导致浮游植物增加,引起海洋初级生产的异常.