基于ARMAV模型的国内海洋捕捞与海水养殖产量的分析

为了揭示国内海洋捕捞和海水养殖产量的相关关系,准确地跟踪并预测海洋捕捞和海水养殖产量的短期未来趋势,利用时序分析方法对1954—2006年国内海洋捕捞和海水养殖产量数据建立了多维自回归滑动平均（ARMAV）模型。该方法不仅避免了分别使用自回归滑动平均（ARMA）模型对两序列建模未考虑序列间关系的弊端,还通过数据的先期平稳化处理而使得算法的运用更具有针对性。图像与误差计算结果均表明,用本研究中给出的ARMAV（2,1,2）算法对两序列进行跟踪及预测具有效性。     

Consumer attitudes to different pig production systems: a study from mainland China

In many countries consumers have shown an increasing interest to the way in which food products are being produced. This study investigates Chinese consumers’ attitudes towards different pig production systems by means of a conjoint analysis. While there has been a range of studies on Western consumers’ attitudes to various forms of food production, little is known about the level of Chinese consumers’ attitudes. A cross-sectional survey was carried out with 472 participants in 6 Chinese cities. Results indicate that Chinese consumers prefer industrial pig production systems, where traditional pig breeds are raised, over large-scale and small family farms. Farms with maximum attention to food safety, which furthermore can provide lean meat with consistent quality, are also preferred. Imported pig breeds and tasty but variable meat were rejected. A 3-cluster solution found that consumers from cluster 1 focus almost exclusively on the food safety aspect (food safety focused). Consumers from cluster 2 (indifferent) show weak overall attitudes to pig production systems in general. Cluster 3 (industrial production oriented) stands out by being very positive about industrial, large-size farms and consistent quality. From a Chinese consumer’s perspective, the industrial approach seems to represent values such as achievement and evolution, as well as quality and safety, since pig production is moving away from low-cost, low-quality, and low-safety family-scale systems. A complex set of rural and environmental development, quality aspects, and food safety measures are challenges that must be met by the stakeholders of pig production systems in China.     

我国海洋捕捞渔民群体收入问题浅析

总结概括我国海洋捕捞渔民群体存在的收入问题表现,并从资源状况、管理政策等多个方面进行分析,指出造成问题的本质:有限的海洋渔业资源不足以支撑严重过剩的捕捞产能,而且当前的外部环境又在加重这种失衡,相应的管理措施不能同时兼顾改善海洋渔业资源状况、降低过剩捕捞产能、维持捕捞渔民收益、缩小渔民收入差距。因此,为解决捕捞渔民群体收入问题,促进海洋捕捞渔民增收,应强化渔业资源养护和管理,保证海洋捕捞渔民的生产物质基础;建立健全传统捕捞渔民渔业权益保障机制,保障海洋捕捞渔民公平发展的权利;完善渔业管理政策制度,确保海洋捕捞渔民权利的均等性;加强对传统捕捞渔民新技术和其他劳动技能培训,提高捕捞渔民综合素质,拓展就业渠道,强化就业能力。     

我国海洋捕捞产值修正与渔获平均价格变化趋势分析

海洋捕捞产量与产值数据是反映我国海洋捕捞渔业发展状况的客观依据,对于分析产业现状、制定相关政策措施等具有重要意义。渔业统计部门已对1997—2006年间海洋捕捞产量指标进行了修正,但同期产值数据却未作调整。通过对1997—2006年我国海洋捕捞产量统计数据调整前后变化规律进行分析,借助未调整的海洋捕捞产值数据,在提出3点基本假设的基础上,分别构建了基于产值回溯的修正原理和基于平均价格回溯的修正原理,并对1997—2006年海洋捕捞产值进行了修正。结果显示,2种不同原理对海洋捕捞产值的修正结果存在一定差异,并最终以2种不同原理修正结果的平均值作为结论;从修正后结果看,海洋捕捞产值年均增长率达到13.59%。还分析了1997—2011年海洋捕捞产品平均价格增长趋势特征。1997—2006年海洋捕捞产值修正结论将为有关政府部门、研究者进行海洋捕捞渔业产值经济分析提供一定的数据支撑。     

Oceanic dimethylsulfide: production during zooplankton grazing on phytoplankton

About half the biogenic sulfur flux to the earth's atmosphere each year arises from the oceans. Dimethylsulfide (DMS), which constitutes about 90% of this marine sulfur flux, is presumed to originate from the decomposition of dimethylsulfoniopropionate produced by marine organisms, particularly phytoplankton. The rate of DMS release by phytoplankton is greatly increased when the phytoplankton are subjected to grazing by zooplankton. DMS production associated with such grazing may be the major mechanism of DMS production in many marine settings.     

Spreading dead zones and consequences for marine ecosystems

Dead zones in the coastal oceans have spread exponentially since the 1960s and have serious consequences for ecosystem functioning. The formation of dead zones has been exacerbated by the increase in primary production and consequent worldwide coastal eutrophication fueled by riverine runoff of fertilizers and the burning of fossil fuels. Enhanced primary production results in an accumulation of particulate organic matter, which encourages microbial activity and the consumption of dissolved oxygen in bottom waters. Dead zones have now been reported from more than 400 systems, affecting a total area of more than 245,000 square kilometers, and are probably a key stressor on marine ecosystems.     

发达国家海洋经济发展战略及对中国的启示

中国海洋经济的发展必须借鉴国外海洋经济发展的成功经验.从全球海洋经济开发的总体趋势出发,分析了日本、挪威、英国、澳大利亚、美国、加拿大6个发达国家海洋经济发展战略,总结了6国海洋经济发展对我国发展海洋经济的启示.     

Strong top-down control in southern California kelp forest ecosystems

Global-scale changes in anthropogenic nutrient input into marine ecosystems via terrestrial runoff, coupled with widespread predator removal via fishing, have created greater urgency for understanding the relative role of top-down versus bottom-up control of food web dynamics. Yet recent large-scale studies of community regulation in marine ecosystems have shown dramatically different results that leave this issue largely unresolved. We combined a multiyear, large-scale data set of species abundances for 46 species in kelp forests from the California Channel Islands with satellite-derived primary production and found that top-down control explains 7- to 10-fold more of the variance in abundance of bottom and mid-trophic levels than does bottom-up control. This top-down control was propagated via a variety of species-level direct and indirect responses to predator abundance. Management of top-down influences such as fishing may be more important in coastal marine ecosystems, particularly in kelp forest systems, than is commonly thought.     

世界头足类资源开发现状及我国远洋鱿钓渔业发展对策

头足类是世界上最具开发潜力的渔业种类之一,已成为世界海洋捕捞业的重要组成。根据1970—2016年世界各国头足类生产统计数据,利用灰色关联方法,对世界头足类渔业及其组成进行了分析;结合我国远洋鱿钓渔业的发展状况,指出存在的问题并提出发展对策。分析认为:1970—2016年世界头足类捕捞产量总体上呈现出较为稳定的增长趋势,年增长率达到3.68%,远高于同期世界海洋捕捞产量的增长率,2014年达到历史最高产量。2010—2016年,头足类捕捞产量占世界捕捞产量的比重稳定在4.5%～6.0%。不同年代柔鱼科、枪乌贼科、乌贼科和章鱼科的产量组成及其比重有所差异,主要生产国家和地区的产量排序发生了很大的变化,2010年代各科所占比重依次为柔鱼类(58.41%)、枪乌贼类(11.98%)、章鱼类(8.92%)、乌贼类(8.40%)。亚洲在40多年的世界头足类渔业组成中地位极为重要,日本头足类产量从1970年代到1990年代的第1位下降到2010年代的第5位,我国从1970年代的第5位上升到2000年代和2010年代的第1位。对大洋性鱿鱼资源的认知能力、开发能力和掌控能力不足是制约我国远洋鱿钓渔业可持续发展的主要问题,为此提出建立与国际接轨的全球远洋渔业资源调查与生产性探捕的监测体系,研制全球远洋鱿钓渔业渔海况信息服务系统,建立自主产权的渔具及标准化装备体系,研发渔获品质控制技术与溯源体系,开展基于物联网工程的远洋渔业信息化建设,建立起我国主导研究的头足类渔业资源评估体系等建议与对策。     

Recent biogenic phosphorite: concretions in mollusk kidneys

Phosphorite concretions have been detected in the kidneys of two widespread species of mollusks, Mercenaria mercenaria and Argopecten irradians, which have relatively high population densities. These concretions are the first documentation of the direct biogenic formation of phosphorite grains. The concretions are principally amorphous calcium phosphate, which upon being heated yields an x-ray diffraction pattern which is essentially that of chlorapatite. These concretions appear to be a normal formation of the excretory process of mollusks under reproductive, environmental, or pollutant-induced stress. Biogenic production of phosphorite concretions over long periods of time and diagenetic change from amorphous to crystalline structure, coupled with secondary enrichment, may account for the formation of some marine phosphorite desposits which are not easily explained by the chemical precipitation-replacement hypothesis.     

构建我国海洋综合协调机制的初步研究

我国海洋管理体制存在着缺乏高层协调机构、协同作用机制和信息共享机制等弊端,因此为了完善我国海洋管理体制,需要建立海洋综合协调机制。美国和日本这两种不同海洋管理体制的国家都非常重视协调机制的建设,在我国现有机构的基础上,借鉴国外的建设经验,提出适合我国海洋管理协调机制的具体建议：建立健全的多主体合作机构、咨询和参谋机构,构建海洋综合协调组织模式图,并完善海洋管理信息系统的建设,为各涉海主体搭建有效沟通的平台,实现海洋综合管理的统筹和协调,完善我国海洋管理体制。     

中国海洋捕捞渔业供给侧存在的问题与改革对策

海洋捕捞业贡献了我国水产品产量的约五分之一,但渔业资源衰退与捕捞强度过大的矛盾亟需破解,实施供给侧结构性改革是必由之路。首先对我国海洋捕捞渔业的总产量变化趋势、省份结构、品种结构、海区结构、作业方式结构等特征进行梳理,分析认为我国海洋捕捞业供给侧的突出问题是海洋捕捞产量远超资源可捕量和渔获物中鱼类所占比重仍呈增长趋势。最后,以海洋捕捞渔业健康持续发展为目标,阐述了我国海洋捕捞渔业供给侧改革的重点任务与对策措施。     

中国水产品产量结构变化特征研究

水产品产量结构是反映渔业产业内部结构和外部资源变化的重要指示器。利用1997～2010年水产品产量数据,从生产水域、生产方式和产品种类三个不同角度,对我国水产品产量结构变化特征进行了分析。结果表明:(1)从生产水域来看,海水产品仍是水产品市场供给的主要来源,预计到2014年淡水产品将取代海水产品地位,成为市场主力;(2)从生产方式来看,自2006年海水养殖比重超过海水捕捞比重后,标志着渔业完全实现"以养为主"的发展战略,淡水养殖产量的比重最高,已超过40%;(3)从产品种类来看,淡水鱼类、海水贝类和海水鱼类是水产品产量结构的主要品种。分析认为淡水渔业将会成为未来较长时期我国水产品供给的主要来源。建议制定淡水渔业发展战略,科学指导淡水渔业产业发展,促进淡水渔业可持续发展。     

The role of indigenous tillage systems in sustainable food production

Farmers in developed countries have established various tillage practices for crop production. These include plowing, disking, subsoiling, harrowing, field cultivating, rotary hoeing, and row-crop cultivating. But these conventional tillage practices necessitate the use of heavy equipment that often causes soil compaction, impairs soil physical conditions, and creates conditions leading to soil erosion. Many Western countries, studying their conventional tillage systems through the new perspective of sustainable approaches to agriculture, are developing new tillage practices, called conservation tillage, which limit tillage to essential operations and prevent damage to soil. The majority of the small-scale farmers in developing countries use indigenous tillage systems. These are low-cost, locally adapted technologies that reflect considerable knowledge of sustainable agriculture. Ironically, the new conservation tillage systems currently being developed in the West have many characteristics of indigenous tillage systems. This paper compares conventional, conservation, and indigenous tillage practices, using examples from the United States and India, and concludes that, for sustainable food production, indigenous tillage practices in developing countries should continue to be used.     

我国水产养殖对环境的影响及其可持续发展

近年来,我国水产养殖业有了突飞猛进的发展,但同时也对水环境造成了一定的影响。通过分别论述池塘、湖库、海水等不同养殖系统对自身养殖水体及周围水域的影响,探讨了环境友好的工厂化养殖和生态养殖模式的现状及发展前景,提出我国水产养殖业的可持续发展方向:结合生态养殖和封闭式循环水工厂化养殖模式,应用危害分析与关键控制点(HACCP)管理系统,发展有机健康养殖模式。在此基础上,对我国水产养殖业可持续发展所需的理论研究及法律法规支持进行了归纳。     

海洋立管气液两相流动模拟研究进展

随着海洋石油工业的发展,从20世纪70年代的浅海立管到21世纪的深海立管,海洋管道发展了多种新的形式,如悬链线立管、S形立管等。对于各种混输立管系统,严重段塞流等不稳定流动会造成设备损坏,严重影响安全生产。因此,实现立管流动的准确模拟,通过合理设计和科学运行控制、消除严重段塞流,具有重要意义。综述了国内外海洋混输立管流动模拟的研究成果,包括L形立管和柔性立管的实验研究、模型模拟及软件模拟的主要进展。指出了当前研究中存在的问题及未来的研究方向,可为进一步开展立管流动模拟研究提供参考。     

Carbon-13 and carbon-14 abundances in alaskan aquatic organisms: delayed production from peat in arctic food webs

Inputs of terrestrial peat carbon to the nearshore Alaskan Beaufort Sea from erosion and fluvial transport are of the same magnitude as in situ primary production within 10 kilometers of shore. Nevertheless, carbon-13/carbon-12 ratios and carbon-14 abundances in marine organisms show that only small amounts of the terrestrial carbon are transferred beyond the microbial level. Freshwater organisms, however, are heavily dependent on peat, as shown by pronounced seasonal radiocarbon depressions in resident fish and ducks. Tundra ponds and lakes are areas where accumulated terrestrial peat carbon is apparently transferred to aquatic insect larvae and passed on to higher organisms. The lack of functionally analogous abundant marine prey organisms may explain why peat carbon is not efficiently transferred to apical food web species in the marine environment.     

Bacterial taxa that limit sulfur flux from the ocean

Flux of dimethylsulfide (DMS) from ocean surface waters is the predominant natural source of sulfur to the atmosphere and influences climate by aerosol formation. Marine bacterioplankton regulate sulfur flux by converting the precursor dimethylsulfoniopropionate (DMSP) either to DMS or to sulfur compounds that are not climatically active. Through the discovery of a glycine cleavage T-family protein with DMSP methyltransferase activity, marine bacterioplankton in the Roseobacter and SAR11 taxa were identified as primary mediators of DMSP demethylation to methylmercaptopropionate. One-third of surface ocean bacteria harbor a DMSP demethylase homolog and thereby route a substantial fraction of global marine primary production away from DMS formation and into the marine microbial food web.     

养殖技术对山东省海水养殖渔业可持续发展的作用

根据山东省1978-1999年间海水养殖面积、产量和单产统计资料，解析了海水养殖业发展过程中，养殖产量受养殖面积增加和养殖单产水平变化的影响程度，研究表明：（1）近20斫来，山东省海水养殖单产提高幅度很小，对海水养殖产量增长的贡献率较低；（2）养殖面积保持较高的增长率，尤其是90年代中期以后，养殖面积的快速增长与养殖单产的急剧下降形成鲜明对比，外延性扩大再生产比例过高，内涵性扩大再生产比例过低是过去20年山东省海水养殖业发展的主要特征，可以认为不断提高养殖技术是实现山东省海水养殖业可持续发展的关键所在。     

养殖技术对山东省海水养殖渔业可持续发展的作用

根据山东省1978-1999年间海水养殖面积、产量和单产统计资料，解析了海水养殖业发展过程中，养殖产量受养殖面积增加和养殖单产水平变化的影响程度，研究表明：（1）近20斫来，山东省海水养殖单产提高幅度很小，对海水养殖产量增长的贡献率较低；（2）养殖面积保持较高的增长率，尤其是90年代中期以后，养殖面积的快速增长与养殖单产的急剧下降形成鲜明对比，外延性扩大再生产比例过高，内涵性扩大再生产比例过低是过去20年山东省海水养殖业发展的主要特征，可以认为不断提高养殖技术是实现山东省海水养殖业可持续发展的关键所在。