渔业碳汇与碳汇渔业定义及其相关问题的辨析

本文基于联合国政府间气候变化专门委员会(IPCC)关于碳汇和碳源的解释和水生植物固碳特点,对2010年提出的渔业碳汇和碳汇渔业的定义进行修订,强调了渔业碳汇功能和增汇的基本表达方式和水生植物在渔业碳汇中的重要作用,进一步解释了通过水生藻类养殖、滤食性贝类和鱼类等养殖、渔业生物群体捕捞和增殖等渔业生产活动促进水生生物“移出和储存”CO2等温室气体的过程和机制。分析了贝类养殖在不需要投放饵料的前提下,通过滤食浮游植物及有机碎屑等颗粒有机物大量使用水体中CO2的过程及机制,从能量收支层面论述了使用碳、移出碳、储存碳和释放碳4个碳库的特征及其数量关系,进而证实贝类养殖提升了水域生态系统碳汇能力,是碳汇而不是碳源。贝藻养殖碳汇评估结果表明,随着海水养殖生产持续发展,近20年我国近海贝藻养殖碳汇有较大幅度的增加,总碳汇量从2001年394万t增加到2020年659万t,其中近三年(2018—2020)平均总碳汇量为648万t (相当于每年义务造林87万hm2);净碳汇量从2001年255万t增加到2020年430万t,近三年(2018—2020)平均净碳汇量为422万t (相当于每年义务造林56万hm2)。最后,提出了健康持续、深入发展碳汇渔业的相关建议。     

国际海洋生物碳汇研究进展

海洋是地球上最大的碳库.整个海洋中蓄积的碳总量达到39×1012t,占全球碳总量的93%,约为大气的53倍.这些碳或重新进入生物地球化学循环,或被长期储存起来;而其中一部分被永久地储存在海底.根据联合国<蓝碳>报告,地球上超过一半(55%)的生物碳或是绿色碳捕获是由海洋生物完成的,这些海洋生物包括浮游生物、细菌、海藻、盐沼植物和红树林.本文综述了近年国际上对海洋生物碳汇的研究结果,阐述了海洋生物固碳的机制、海洋生物碳汇的现状及其修复措施,同时评价和论述了海水贝藻养殖作为渔业碳汇的地位与作用.     

中国近海生态系统碳循环与生物固碳

本文系统总结了近几年来中国近海海-气界面碳通量及控制因素、近海碳循环的关键过程以及近海生物固碳强度的研究进展,提出了中国近海渔业碳汇过程研究应关注的主要科学问题.近海海-气界面碳通量过程、生物泵过程、颗粒物沉降与释放以及捕捞/养殖碳转移过程是中国近海生态系统碳循环的主要控制过程.中国近海在总体上是大气二氧化碳的汇,年吸收3 000万～5 000万t碳,但在部分浅海海域如胶州湾、长江口等是大气二氧化碳的源:中国近海浮游植物的年固碳量可达6.39亿t,春季和夏季浮游植物固碳占全年的65.3%.南海浮游植物固碳达4.16亿t,为渤海、黄海和东海的2倍.渔业捕捞与海水养殖可明显增加海洋碳汇,仅就近几年大型藻养殖而言,每年可多固定40万t碳,如果每年的养殖量增加5%,到2020年大型藻养殖可固定碳93万t/年,所以,为增加渔业捕捞与海水养殖碳汇,必须加强揭示渔业碳汇海域生态环境、建立渔业碳增汇强度评估方法以及明确渔业资源利用碳再生循环周期等研究.     

海洋牧场渔业碳汇研究进展

海洋通过“溶解度泵”和“生物泵”完成碳汇过程，且具有碳固存容量大、储存时间长的显著优势，可有效缓解CO2排放产生的温室效应，在应对全球气候变化中发挥着不可替代的作用。渔业是人类利用海洋的基础生产活动，对近海碳循环过程具有重要的影响，渔业碳汇是海洋碳汇不可或缺的组成部分。海洋牧场作为一种以水域栖息地修复、水生生物资源养护为主旨的新型渔业模式，通过增殖水生生物资源量，提升生物固碳量，实现渔业对海洋碳汇的扩增。本文针对我国对海洋牧场的界定，梳理了国内外对海洋牧场关键碳汇因子固碳机理及其过程和潜能等方面的研究现状，浅析了海草床、牡蛎礁等典型海洋牧场生态系统在近海碳汇扩增中的重要作用。建议在海洋牧场固碳机理与碳循环过程、海洋牧场碳汇扩增技术和海洋牧场碳汇计量方法等方面开展重点研究，以期为渔业绿色发展，扩增海洋碳汇和服务“双碳”战略提供科学参考。     

庙岛群岛毗邻海域秋季底栖食物网潜在碳来源贡献及对碳汇渔业的思考

陆架边缘海是全球海洋重要的碳汇区域,而近岸岛屿毗邻海域作为最具代表性的边缘海域,具有来自海洋与陆地的不同碳来源,在碳循环和海洋碳汇中发挥着重要作用。本研究基于碳氮稳定同位素方法,利用贝叶斯混合模型,分析2020年秋季庙岛群岛毗邻海域底栖食物网中不同碳来源(浮游植物、大型藻类、悬浮颗粒有机物和底质有机物)对主要消费者类群(水生底栖无脊椎动物、杂食性鱼类、底栖食性鱼类和肉食性鱼类)的相对贡献,并以此对海洋碳汇和碳汇渔业展开了讨论。结果显示,庙岛群岛毗邻海域秋季底栖食物网生物类群的潜在碳来源主要为藻类(包括浮游植物和大型藻类)和海底底质有机质(SOM),但悬浮颗粒有机物(POM)的贡献较低。碳来源主要以内源性碳(海源)为主。由于大型藻类对水生底栖无脊椎动物的贡献明显高于鱼类,在碳汇渔业的指导下,合理科学地进行藻类增养殖,并通过贝类或以贝藻为食的鱼类混和养殖可能增加碳汇能力,从而促进碳汇渔业的发展。     

中国近海海藻养殖及碳汇强度估算

海藻养殖是渔业碳汇的重要形式,碳汇生态功能显著。本实验以1999—2012年《中国渔业统计年鉴》统计数据为基础,对中国及浙江近海藻类养殖的产量、结构进行了分析,并对其固碳强度进行了估算。中国近海海藻养殖以海带、裙带菜、紫菜、江蓠等为主,期间年均总产量为141.87万t,各类海藻养殖产量所占比例分别为海带(60.29%)、裙带菜(7.92%)、紫菜(5.67%)、江蓠(5.39%)。浙江近海海藻养殖以紫菜、海带、羊栖菜、苔菜等为主,各类海藻养殖产量所占比例分别为紫菜(51.83%)、海带(27.73%)、羊栖菜(12.72%)、苔菜(1.27%)。浙江近海海藻养殖总产量占全国总产量的份额不高(2.55%),但养殖结构独特,部分种类的海藻养殖产量在全国同种类海藻养殖量中占有较高份额,其中苔菜占83.00%,羊栖菜占68.29%,紫菜占23.53%。1999—2012年,全国海藻年均固碳量为41.85万t/a,固碳量在2012年最高达51.50万t,整体呈现上升趋势。其中,海带年均固碳量在各类海藻中最高达26.45万t/a,其次是裙带菜3.23万t/a、紫菜2.24万t/a、江蓠2.01万t/a。浙江近海养殖海藻年均固碳量为1.03万t/a,约占全国年均固碳量的2.47%。为满足低碳经济发展的需求,建议加强近海自然碳汇及其环境的保护和管理,大力发展以海水养殖为主体的碳汇渔业,开展碳汇渔业关键技术与产业示范工程研究及海洋生物碳汇功能与碳汇渔业潜力的基础科学研究。     

海洋捕捞业的碳汇功能

海洋捕捞业是碳汇渔业之一,人类通过收获渔获物将食物链/网传递的海洋植物光合作用固定的碳移出水体,在海洋碳汇中发挥着重要的作用。根据对海洋捕捞业碳汇功能的评估方法,得出1980～2000年间渤海捕捞业的年固碳量是283～1008万t,黄海捕捞业的年固碳量是361～2613万t。尽管加大捕捞产量增加了从海洋生态系统移出浮游植物的固碳量,但随着捕捞业的高速发展,其碳汇功能却被削弱了,黄渤海捕捞业的年固碳量最大分别减少了23%和27%。而且由于资源量的下降,封存于水体和海底的碳减少,不利于捕捞业发挥可持续的碳汇功能。渤海2009年增殖放流的中国对虾使捕捞业增加1.66万t的固碳量,因此,需要采取包括增殖放流在内的一些措施来恢复和增强海洋捕捞业的碳汇功能,最终形成资源养护型的捕捞业。     

浙南浅海鱼类养殖概况及渔业统计的探讨

正浅海鱼类养殖不但是海水养殖的重要组成部分,而且由于浅海鱼类养殖的开放性,其对海洋环境和资源也有重要的影响。按渔业统计要求,普通网箱养殖面积以平方米计,深水网箱养殖面积以立方米计,由于统计人员对普通网箱和深水网箱区分界限模糊,统计数据往往与实际情况相差较大,不能很好地为养殖生产指导和决策提供真实依据。为了摸清浙江南部温州海水鱼类浅海养殖的真实情况,浙江省海洋水产养殖研究所对浙南温州的浅海     

海洋碳汇研究进展及南海碳汇渔业发展方向探讨

二氧化碳（CO2）是温室气体的主要成分,近代工业化的迅速发展导致碳的排放量不断增长,自2005年2月16日《京都议定书》正式生效以来,节能减排、碳＂源＂、碳＂汇＂等概念越来越受到关注。海洋占地球面积的70%以上,是最大的＂碳库＂,约占全球碳总量的93%,约为大气的50倍。海洋的固碳机制主要包括碳酸盐体系驱动的＂溶解度泵＂和浮游生物驱动的＂生物泵＂过程,这些过程对大气CO2的浓度和全球碳循环的系统过程都有重要的影响。同时,近海由于受人类活动的显著影响,尤其是近岸的渔业活动,对碳循环和海洋增汇有着重要的影响。文章对主要的碳源和碳汇以及海洋固碳机制研究进展进行了综述,并探讨了南海碳汇渔业发展的重点研究方向。     

广东海水鱼类养殖技术现状及可持续发展

９０年代以来，广东的海水鱼类养殖发展迅猛，１９９９年海水鱼类养殖面积达４．３万公顷，海水鱼类养殖总产量１８万ｔ，占全国海水鱼类养殖总产量的４５％，年养殖增值４０多亿元，成为广东海洋经济的重要产业。但是，随着养殖时间的延长，病害开始发生并蔓延，给生产造成严重损失。迄今为止，广东放养的石斑鱼类、笛鲷科鱼类、石鲈科鱼类等苗种，４０％来自捕捞的野生鱼苗，５０％依靠从台湾、泰国等地进口人工鱼苗，不仅耗费大量外汇，质量也不保证，而且带来病害，而大量捕捞天然鱼苗，对自然资源将不断造成破坏。这种状况与海水鱼类养…     

大型海藻碳汇效应研究进展

大型海藻光合作用是海域初级生产力的来源之一,是海洋碳循环中关键的一环。大型海藻可通过光合作用有效地吸收海水中溶解的无机碳以及大气中的CO2,将其转化为有机碳并释放O2,光合作用的产物除支持生态系统外,还以有机物的形式埋藏在沉积物中,进而形成碳的汇。大型海藻的养殖和增殖对CO2的减排、减缓海洋酸化、扩增海洋碳汇效应以及缓解气候变化都有重要意义。本文就大型海藻碳汇机理、潜力以及大型海藻碳汇能力的扩增途径进行了综述,为大型海藻碳汇效应研究的发展提供了依据。     

The evolution and future of pond and marine fish culture in Hong Kong

Abstract

This paper provides a case study of the evolution of the freshwater food fish and marine food fish culture industries in Hong Kong as a highly urbanized and polluted metropolis. This study lends support to the thesis that marine fish culture is generally more sustainable than pond fish culture, owing to the fact that oceanic resources are relatively less scarce than land resources ‐ even though the transaction costs of delineating and enforcing private property in the former are much higher. The case study gives a brief historical account of the evolution of the freshwater food fish and marine food fish culture industries in Hong Kong, identifies the technical inputs constraining the survival and prospects of these industries, and evaluates the relevance of the private property rights approach to their sustainability. Examination of the culture industries reveals the differences in property right characteristics of both industries. In addition to the differentiation in the degree of privatization between freshwater food fish and marine food fish culture, the major characteristics and inputs for culture practices in both industries are also examined. A qualitative evaluation of the relative significance of these inputs to the sustainability of the culture industries is provided. It is argued that the escalation in the factor price of land will destroy the local pond fish culture industry even though it is more ‘private’ than marine fish culture, notwithstanding the fact that substantial areas of intertidal ponds are owned by government and that in‐filling of fishponds have been subject to stringent planning control. The policy implications of the case study are spelled out.     

Relationship between feed input and sediment quality of the fish cage farms

ABSTRACT: A study was conducted to examine the variation in fish farm sediment quality with varying organic carbon input in the form of feed. In order to elucidate the seasonal variation in farm sediment quality, relation between seasonal organic carbon input, temperature and sediment quality was studied. The sediment ignition loss, redox potential and acid volatile sulfide sulfur (AVS-S) content showed a correlation with annual organic carbon input. The seasonal AVS-S content showed a significant correlation with the seasonal organic carbon input as well as temperature. Multiple regression analysis revealed that both of these factors explicated 80% of the seasonal variation in AVS-S content. Although redox conditions of the sediment could also be correlated with both the organic carbon input and temperature, the latter seemed to have a greater control. Thus, the farm sediment quality could be directly related to the annual organic carbon input to the fish farm under similar hydrographic conditions. Acid volatile sulfide sulfur content exhibited a significant correlation with both the annual as well as the seasonal organic carbon input. Therefore, AVS-S content proved to be a fairly simple and better indicator for monitoring the fish farm environment for effective farm management and sustainable aquaculture. Importance of size of pellets as a factor affecting the feed input-sediment quality relation is also demonstrated in the present study.     

The vulnerability of fish and macroinvertebrate species with bioactive potential in a Mediterranean marine protected area

1. A high percentage of marine animals produce bioactive compounds that may play a leading role in the discovery of future compounds and drugs of marine origin. However, commercial fishing and other human activities leading to sea warming and pollution may affect these marine animals, even putting them in danger of extinction.
2. To date, no comprehensive studies have evaluated the conservation status of Mediterranean species with bioactive potential, which is crucial to better understanding of how these species cope with the impacts of human activity.
3. The study reviewed the bioactive potential and vulnerability of 833 fish and macro-invertebrate species inhabiting the marine protected area of Cap de Creus and surrounding areas. The most active taxa found were Porifera (49 out of 59 species; 83.0%) and Tunicata (17 out of 27 species; 63.0%). The most vulnerable species were Chondrichthyes (eight out of nine species) and Porifera (nine out of 12 species), which together account for over 75% of species classified as such.
4. Results emphasize the need to introduce specific management measures that protect vulnerable species with bioactive potential as this is a valuable component of marine ecosystems, as well as a potential source of molecules with pharmacological properties beneficial for human health.
5. Marine protected areas can contribute to preserving marine species of medical interest and achieving their sustainable use in the marine biotechnology industry.

     

动植物蛋白源替代鱼粉研究进展

With the fast development of aquaculture, fish meal needs increased in recent years, however the quantity of fish catching decreases gradually. Fishmeal is a limited feed resource, and serious concem exists on the future availability of this feedstuff for incorporation in fish diets. Undoubtedly, fish meal is well recognized as the best dietary protein source for most marine carnivorous fishes which required high dietary protein levels compared to omnivorous or herbivorous fish. Fishmeal is known for their high content of essential amino acids and fatty acids, low carbohydrates, high digestibility, low levels of anti-nutritional factors (for fresh fish meal) and is a very good source of minerals and is highly palatable. Thus fish meal is in high demand as the protein source for many formulated diets. However, production of fish meal consumes approximately 35 % of the total global fish catch, and the increasing price and potentially unstable supply in the market could be limiting factors for marine fish culture. There have been strong efforts to define and develop cost-effective protein sources that can, at least partly, substitute for expensive high-quality fish meals in least-cost feed formulations. The search for fish meal substitutes and altemative dietary protein sources is an international research priority that could be of considerable economic advantages. Therefore it is urgent task to find animal and plant protein sources in place of fish meal. Among these, plant feedstuffs have received most attention in recent years, but due to their amino acid unbalances, .presence of anti-nutritional factors and low palatability, a high level of replacement of fish meal with plant feedstuffs in omnivorous fish is generally not well accepted. This paper reviews the research status for other protein sources replacing fish meal based on available information in the literature. Animal and plant protein sources nutrient values are evaluated from the aspect of digestibility, antinutrients, physiological status and suitable supplementation.     

象山港南沙岛不同养殖模式沉积物微生物群落结构分析

通过构建16S rDNA克隆文库对象山港南沙岛不同养殖模式(贝类养殖、藻类养殖及网箱养殖)表层沉积物微生物多样性和群落结构特征进行了比较和分析,共获取136个OUT。其中,贝类养殖区、藻类养殖区和网箱养殖区OTU分别为58、48和57个。各站位OTU分布差异明显,表现出高度的多样性。基于16S rDNA序列的生物多样性和丰富度分析表明,网箱养殖区丰富度指数ACE为739,香浓指数H?为3.8,均为最高值,丰富度指数Chao为245,略低于于贝类养殖区。贝类养殖区丰富度指数Chao为303,在各养殖区中最高。藻类养殖区丰富度指数ACE为174、Chao为89,香浓指数H?为3.6,均为最低值。系统发育分析表明,南沙岛各养殖区的优势种群均为变形菌门(Proteobacteria),但是藻类养殖区微生物群落结构与其他养殖区域相比,16S rDNA克隆文库差异显著,其中根瘤菌属(Rhizobium)及其他光合细菌在藻类养殖区分布较多。网箱养殖区沉积物表层微生物群落中出现了与环境污染密切相关的菌群,如志贺氏菌属(Shigella)、埃希氏菌属(Escherichia)和ε-变形菌纲的微生物种群,揭示网箱养殖对底质沉积物环境的影响较大。     

Survival of the fish pathogen Aeromonas salmonicida in the marine environment

Abstract. The fate of the fish pathogen Aeromonas salmonicida in the marine environment was examined by culture, epifluorcscence microscopy, the indirect fluorescent antibody technique (1FAT), direct viable counts (= Kogure technique) and the assessment of respiratory activity by the reduction of tetrazolium compounds to coloured formazans. In laboratory- based systems containing sediment, water, algae and invertebrates, cells of A. salmonicida were observed microscopically after plate counts on tryptone soya agar declined to zero. Survival was maximal at a salinity of 25%_o, and in wood and sediment, notably mud, rather than the water column.     

海水鱼类网箱养殖水域沉积物有机质的来源甄别

利用稳定碳氮同位素示踪技术,对南沙港网箱养殖水域沉积物中有机质的来源进行了分析研究。结果表明,网箱养殖区(距离网箱边缘100 m范围内)及对照区(距离网箱边缘大于500 m)沉积物的δ13C值分别为(-17.72±1.2)‰和(-12.73±0.38)‰,δ15N分别为(6.44±0.2)‰和(5.61±0.2)‰。网箱养殖区沉积物的有机质来源主要为残饵和鱼类粪便,比例分别占47.70%和27.71%。随着与养殖网箱距离的增加,网箱养殖源有机质(残饵和鱼类粪便之和)的比例降低,变化趋势符合指数方程y=97.167e-0.007 4x(R2=0.848 1),在潮流驱动的沉积物再悬浮及野生鱼类的扰动影响下,网箱养殖源有机质的水平位移可达400 m。鱼类网箱养殖的养殖废物是南沙港水域沉积物有机污染的主要来源。