Trophic cascades in a formerly cod-dominated ecosystem

Removal of top predators from ecosystems can result in cascading effects through the trophic levels below, completely restructuring the food web. Cascades have been observed in small-scale or simple food webs, but not in large, complex, open-ocean ecosystems. Using data spanning many decades from a once cod-dominated northwest Atlantic ecosystem, we demonstrate a trophic cascade in a large marine ecosystem. Several cod stocks in other geographic areas have also collapsed without recovery, suggesting the existence of trophic cascades in these systems.     

Climate impact on plankton ecosystems in the Northeast Atlantic

It is now widely accepted that global warming is occurring, yet its effects on the world's largest ecosystem, the marine pelagic realm, are largely unknown. We show that sea surface warming in the Northeast Atlantic is accompanied by increasing phytoplankton abundance in cooler regions and decreasing phytoplankton abundance in warmer regions. This impact propagates up the food web (bottom-up control) through copepod herbivores to zooplankton carnivores because of tight trophic coupling. Future warming is therefore likely to alter the spatial distribution of primary and secondary pelagic production, affecting ecosystem services and placing additional stress on already-depleted fish and mammal populations.     

A global map of human impact on marine ecosystems

The management and conservation of the world's oceans require synthesis of spatial data on the distribution and intensity of human activities and the overlap of their impacts on marine ecosystems. We developed an ecosystem-specific, multiscale spatial model to synthesize 17 global data sets of anthropogenic drivers of ecological change for 20 marine ecosystems. Our analysis indicates that no area is unaffected by human influence and that a large fraction (41%) is strongly affected by multiple drivers. However, large areas of relatively little human impact remain, particularly near the poles. The analytical process and resulting maps provide flexible tools for regional and global efforts to allocate conservation resources; to implement ecosystem-based management; and to inform marine spatial planning, education, and basic research.     

南极凯尔盖朗海台南象海豹繁殖后运动行为特征分析

南象海豹(Mirounga leonina)为南极海洋生态系统中的重要捕食者,研究该生物行为特征在生态学与生物海洋学方面有着重要意义,但针对凯尔盖朗地区南象海豹的区域性行为特点研究则少有论及。基于凯尔盖朗海台北部安置在南象海豹身上的盐度-温度-深度剖面仪(Conductivity-temperature-depth,CTD)所收集的数据,运用切换状态空间模型(Switching state-space model,SSSM)预测了南象海豹的真实水平运动状况,并分析了其觅食时对水团利用情况以及潜水特征。结果表明:水平方向上,食物资源的不均匀分布驱动南象海豹向生产力更高区域迁徙,它们主要聚集在3个生产力较高的区域进行觅食,其中凯尔盖朗海台东部的觅食区为大部分南象海豹的迁徙目标;垂直方向上,南象海豹的潜水行为不受光照水平影响且个体间运动表现差异显著,但具有频次高、深度大的特征,同时将捕食区间限制在冬季水(Winter water, WW)附近,这可能是在捕食对象分布与种间竞争之间进行权衡的结果。研究结果丰富了对凯尔盖朗群岛南象海豹繁殖后运动行为的认知,以期为今后更好地了解海洋捕食者的运动行为和生态特性,从而进一步阐释南极生态系统功能。     

Species Diversity and Invasion Resistance in a Marine Ecosystem

Theory predicts that systems that are more diverse should be more resistant to exotic species, but experimental tests are needed to verify this. In experimental communities of sessile marine invertebrates, increased species richness significantly decreased invasion success, apparently because species-rich communities more completely and efficiently used available space, the limiting resource in this system. Declining biodiversity thus facilitates invasion in this system, potentially accelerating the loss of biodiversity and the homogenization of the world's biota.     

Animals as an energy source in third world agriculture

Agricultural development programs have so far been largely unable to meet the food needs of the world's poorest. Increased food production can be achieved only from more intensive agriculture, which requires greater energy inputs per farm worker. Problems of technological infrastructure and escalating oil prices appear to preclude the spread of mechanization to Third World agriculture at this time. Efficient utilization of grazing animals in specific integrated farming systems could not only increase energy inputs through draft and transportation but also increase the yield of high-grade products and by-products from the renewable energy of biomass. An approach to development based on animal agriculture systems is suggested that might initiate a self-sustaining, more productive agriculture requiring only small inputs of fossil-fuel energy.     

Impacts of fishing low-trophic level species on marine ecosystems

Low-trophic level species account for more than 30% of global fisheries production and contribute substantially to global food security. We used a range of ecosystem models to explore the effects of fishing low-trophic level species on marine ecosystems, including marine mammals and seabirds, and on other commercially important species. In five well-studied ecosystems, we found that fishing these species at conventional maximum sustainable yield (MSY) levels can have large impacts on other parts of the ecosystem, particularly when they constitute a high proportion of the biomass in the ecosystem or are highly connected in the food web. Halving exploitation rates would result in much lower impacts on marine ecosystems while still achieving 80% of MSY.     

Biomarker evidence for photosynthesis during neoproterozoic glaciation

Laterally extensive black shales were deposited on the S?o Francisco craton in southeastern Brazil during low-latitude Neoproterozoic glaciation approximately 740 to 700 million years ago. These rocks contain up to 3.0 weight % organic carbon, which we interpret as representing the preserved record of abundant marine primary productivity from glacial times. Extractable biomarkers reflect a complex and productive microbial ecosystem, including both phototrophic bacteria and eukaryotes, living in a stratified ocean with thin or absent sea ice, oxic surface waters, and euxinic conditions within the photic zone. Such an environment provides important constraints for parts of the "Snowball Earth" hypothesis.     

Resource use efficiency,ecological intensification and sustainability of intercropping systems

The rapidly growing demand for food, feed and fuel requires further improvements of land and water management, crop productivity and resource-use efficiencies.Combined field experimentation and crop growth modelling during the past five decades made a great leap forward in the understanding of factors that determine actual and potential yields of monocrops.The research field of production ecology developed concepts to integrate biological and biophysical processes with the aim to explore crop growth potential in contrasting environments.To understand the potential of more complex systems(multi-cropping and intercropping) we need an agro-ecosystem approach that integrates knowledge derived from various disciplines: agronomy, crop physiology, crop ecology, and environmental sciences(soil, water and climate).Adaptation of cropping systems to climate change and a better tolerance to biotic and abiotic stresses by genetic improvement and by managing diverse cropping systems in a sustainable way will be of key importance in food security.To accelerate sustainable intensification of agricultural production, it is required to develop intercropping systems that are highly productive and stable under conditions with abiotic constraints(water, nutrients and weather).Strategies to achieve sustainable intensification include developing tools to evaluate crop growth potential under more extreme climatic conditions and introducing new crops and cropping systems that are more productive and robust under conditions with abiotic stress.This paper presents some examples of sustainable intensification management of intercropping systems that proved to be tolerant to extreme climate conditions.     

The status of the world's land and marine mammals: diversity, threat, and knowledge

Knowledge of mammalian diversity is still surprisingly disparate, both regionally and taxonomically. Here, we present a comprehensive assessment of the conservation status and distribution of the world's mammals. Data, compiled by 1700+ experts, cover all 5487 species, including marine mammals. Global macroecological patterns are very different for land and marine species but suggest common mechanisms driving diversity and endemism across systems. Compared with land species, threat levels are higher among marine mammals, driven by different processes (accidental mortality and pollution, rather than habitat loss), and are spatially distinct (peaking in northern oceans, rather than in Southeast Asia). Marine mammals are also disproportionately poorly known. These data are made freely available to support further scientific developments and conservation action.     

Depletion, degradation, and recovery potential of estuaries and coastal seas

Estuarine and coastal transformation is as old as civilization yet has dramatically accelerated over the past 150 to 300 years. Reconstructed time lines, causes, and consequences of change in 12 once diverse and productive estuaries and coastal seas worldwide show similar patterns: Human impacts have depleted >90% of formerly important species, destroyed >65% of seagrass and wetland habitat, degraded water quality, and accelerated species invasions. Twentieth-century conservation efforts achieved partial recovery of upper trophic levels but have so far failed to restore former ecosystem structure and function. Our results provide detailed historical baselines and quantitative targets for ecosystem-based management and marine conservation.     

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.     

森林生态系统定位研究网络综述

从生态系统定位研究到形成网络是当今世界生态学的发展趋势。本文着重阐述美国和中国森林生态系统定位研究研究网络的形成与发展，并提出21世纪与全球气候变化相关的重要研究课题。     

头足类硬组织的稳定同位素研究进展

头足类作为一种重要的海洋无脊椎动物,在世界海洋生态系统中扮演着非常重要的角色。而目前对其捕食活动和摄食情况的研究不多。稳定同位素作为新型应用技术,被广泛应用于生态系统的研究中。头足类作为捕食者,其体内有大量的碳(C)、氮(N)、氧(O)等稳定同位素,且其硬组织是稳定同位素积累的优良载体,因此通过稳定同位素示踪的方法,分析硬组织各部位稳定同位素含量及其分布,可为了解头足类在海洋生态系统中所处的地位提供手段和方法。根据国内外研究现状,重点分析了耳石、角质额和内壳等硬组织稳定同位素在头足类摄食生态中的应用,并进行了总结和归纳,同时对今后的研究提出了建议。     

生物技术在农业中的应用

农业是生物技术研究和应用最直接最广阔的领域。我国农业生物技术的研究自７０年代开始，２０多年来已在细胞工程、胚胎工程、动植物基因工程育种方面取得了突出的研究和应用成果，有的已达世界先进水平。世界生物技术的迅猛发展已首先在医药、食品、农业三大领域内建起了新型产业，并必然导致世界产业结构及科研体制的巨大变革。     

海南省近海生态系统服务功能价值评估

参照联合国《千年生态系统评估项目》,构建了海南省近海生态系统服务功能体系。采用传统经济价值评估方法,对所构建的10类服务功能进行了定量评估。结果表明:2013年海南省近海生态系统服务功能评估值约为862.52亿元,单位面积海域评估值约为2 811 200元/km~2,低于临近省份广东和广西。其中,文化服务价值最大,占44.19%;其次为供给服务,占36.50%;调节服务价值最小,仅占19.31%。评估结果反映出海南省海洋资源开发潜力仍非常大,海洋生态产业转型迫在眉睫。海南省近海生态系统的污染物处理能力非常有限,在滨海旅游开发中应引起关注。     

Folklore and popular conceptions regarding the fauna of a wetland area on the Caribbean coast of Columbia

In pre-Columbian times, the Zenu Indians established drainage systems in the wetlands of the Colombian Caribbean that enabled them to exploit this rich ecosystem in a sustained manner. Modern inhabitants of the region are, however, exposed to a regimen of periodic flooding that limits their productive activities. In addition, they are surrounded by large cattle ranches that occupy almost all the land and are responsible for the disappearance of forests that sustain the wild fauna. These peasants employ a classification system for the fauna that favors the criterion of habitat over that of morphology to distinguish categories of animals. Secondary forest animals inspire carnival dances, folk tales, poetry, and songs, while insects and other invertebrates are barely represented in the oral tradition. Fishing provides the principal source of protein for many families, but there are no mechanisms to control the use of large nets that exhaust the resource. The capture of reptiles such as iguanas, turtles, and crocodilians is intensive and is not based on studies that determine the state of the populations and the impact of hunting activities. The author draws attention to the need to take into account local representations of animals in programs aimed at conserving the wetlands and their fauna. She discusses the popular nomenclature, knowledge, attitudes, and beliefs regarding the fauna of a wetland region of the Colombian Caribbean to assist in the design of programs for the sustainable exploitation of the resources of this ecosystem, vital to the survival of local fishermen and peasants.     

日本基于渔民管理体系的简析

日本是世界上渔业共同管理发展最早最成功的国家之一,其主要是通过对渔业权和渔业许可证的分配来达到渔业资源管理的目的,其渔业协同组合在渔业资源管理中扮演着重要角色。介绍了渔业协同组合,分析其在日本渔业资源管理中的作用以及日本基于渔民管理体系的优缺点,并对建立渔民管理体系提出几点建议。     

抚育间伐对森林生物量与生产力影响研究进展

森林生物量与生产力在一定程度上是衡量森林质量的重要指标,充裕的生物量同时也会促进生态系统功能的优化,是生态系统稳定的基础,而抚育间伐与森林生物量及生产力存在着密切的关系。针对国内外森林抚育间伐对生物量与生产力影响的研究进行了综述,同时针对我国森林尤其是人工林质量低的现状,提出2点建议:(1)把森林生物量与生产力作为评价森林质量的一项重要指标;(2)对森林抚育对森林生物量与生产力的影响进行长期定位研究。     

深圳市海洋生态系统服务价值的估算

[目的]科学评估深圳市海洋生态系统服务及其价值。[方法]将深圳市海洋生态系统服务划分为4个大类12个亚类,利用成果参照法、市场价值法、替代成本法等方法,对深圳市海洋生态系统服务价值进行评估。[结果]深圳市海洋生态系统服务价值为260 130.61万元,单位面积海洋生态系统服务价值为2.27万元/hm~2。其中,文化服务价值最大,占总服务价值的60.33%;其次是供给服务,占比为20.30%;第三是调节服务,占比为14.79%;最小是支持服务,占比为4.59%。各项服务价值的占比由高到低依次为旅游娱乐、食品供给、物质循环、气候调节、水质净化、干扰调节、知识拓展、空气质量调节、基因资源供给、生物控制、原材料供给、提供生境。[结论]该研究对合理开发和保护海洋资源、促进深圳市海洋生态系统的可持续发展具有重要的战略意义。