What is the ecosystem approach for fisheries management?

The ecosystem approach for fisheries management is a widely accepted concept and various international instruments require its application. However, there are various interpretations of the ecosystem approach and its application almost always brings about confrontations and resistance among managers, proponents, and stakeholders. This paper categorizes the ecosystem approach into four distinguishable types: bycatch mitigation, multi-species management, protection of vulnerable ecosystems, and integrated approach. Furthermore, the lack of identification and understanding of specific management goals is hampering the application of the ecosystem approach. Unless the stakeholders understand and accept the goals, the ecosystem approach will not succeed.     

Surface chlorophyll-a dynamics in the upper Gulf of Thailand revealed by a coupled hydrodynamic-ecosystem model

Although plankton bloom incidents in the upper Gulf of Thailand (UGoT) have been reported, no dynamic investigation of the phenomenon has been conducted. To address this need, a simple pelagic ecosystem model coupled with the Princeton Ocean Model (POM) was employed to investigate seasonal variations in surface chlorophyll-a (chl-a) distributions to clarify phytoplankton dynamics in this area. The results revealed patterns of seasonal chl-a distribution that correspond to local wind, water movement and river discharge. High chl-a patchiness was found to be concentrated near the western coast following westward circulation near the northern coast developed during the northeast monsoon. During the southwest monsoon high concentrations were observed around the northeastern coast due to eastward flow. The simulated results could explain the seasonal shifting of phytoplankton blooms, which typically arise along the western and eastern coasts during the northeast and the southwest monsoons, respectively. Sensitivity analyses of simulated chl-a distributions demonstrate that water stability, including wind-induced vertical currents and mixing, plays significant roles in controlling phytoplankton growth. Nutrients in the water column will not stimulate strong plankton blooms unless upwelling develops or vertical diffusivity is low. This finding suggests an alternative aspect of the mechanism of phytoplankton bloom in this region.     

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江河源区生态系统服务价值评估初探——以江西东江源区为例

应用生态学、生态经济学、福利经济学方法和前人的研究成果,在研究江河源区生态系统价值评估流程和评估方法的基础上,以江西东江源区为研究案例,初步估算出东江源区生态系统服务功能经济总价值为81.0亿元,约为东江源区2004年国内生产总值(GDP)的4.11倍,单位面积生态系统服务功能价值为23121元/hm2,并对估算结果进行了分析.     

基于谱系聚类的全球各国新冠疫情时间序列特征分析

COVID-19暴发以来,世界各国疫情呈现出不同的时序特点,研究不同国家疫情发展模式的特点,揭示其背后的主导因素,可为未来防控策略提供参考。为了揭示不同国家疫情时间序列之间的异同,本文提取了主要疫情国家每日新增病例时间序列的标准差、Hurst指数、治愈率、增长时长、平均增长率、防控效率进行谱系聚类,并从经济、医疗、人文冲突方面对聚类结果进行了成因分析。结果表明,全球疫情发展模式可分为3大类：C型、S型和I型。C型国家时间序列的特点是持续波动上涨,治愈率较低,原因是其人文冲突不利于疫情防控,经济医疗资源经过长时间大量消耗已趋于匮乏,建议在防控中加强宣传疏导,改变观念,统筹分配经济、医疗资源;S型国家时间序列的特点是快速上升后立即下降,并最终保持稳定趋势,总体治愈率较高,其原因是这类国家国内稳定,经济医疗水平较高,以及防控措施及时,建议加强国际合作和科学研究,并为可能到来的二次疫情做好准备;I型国家时间序列特点是缓慢上涨,整体发展趋势不稳定,治愈率较低,原因是其暴发比较晚,程度较小,大部分经济医疗水平以及人文冲突不利于疫情防控,建议汲取较好的防控经验,实施严格的隔离措施,尽量满足疫情期间物资需求,优化治疗方法。     

Subalpine forest water use behaviour and evapotranspiration during two hydrologically contrasting growing seasons in the Canadian Rockies

Hydrological processes in mountain headwater basins are changing as climate and vegetation change. Interactions between hydrological processes and subalpine forest ecological function are important to mountain water supplies due to their control on evapotranspiration (ET). Improved understanding of the sensitivity of these interactions to seasonal and interannual changes in snowmelt and summer rainfall is needed as these interactions can impact forest growth, succession, health, and susceptibility to wildfire. To better understand this sensitivity, this research examined ET for a sub-alpine forest in the Canadian Rockies over two contrasting growing seasons and quantified the contribution of transpiration (T) from the younger tree population to overall stand ET. The younger population was focused on to permit examination of trees that have grown under the effect of recent climate change and will contribute to treeline migration, and subalpine forest densification and succession. Research sites were located at Fortress Mountain Research Basin, Kananaskis, Alberta, where the subalpine forest examined is composed of Abies lasiocarpa (Subalpine fir) and Picea engelmannii (Engelmann spruce). Seasonal changes in water availability from snowmelt, precipitation, soil moisture reserves yielded stark differences in T and ET between 2016 and 2017. ET was higher in the drier year (2017), which had late snowmelt and lower summer rainfall than in the wetter year (2016) that had lower snowmelt and a rainy summer, highlighting the importance of spring snowmelt recharge of soil moisture. However, stand T of the younger trees (73% of forest population) was greater (64 mm) in 2016 (275 mm summer rainfall) than 2017 (39 mm T, 147 mm summer rainfall), and appears to be sensitive to soil moisture decreases in fall, which are largely a function of summer period rainfall. Relationships between subalpine forest water use and different growing season and antecedent (snowmelt period) hydrological conditions clarify the interactions between forest water use and alpine hydrology, which can lead to better anticipation of the hydrological response of subalpine forest-dominated basins to climate variability and change.     

Exploring sustainable aquaculture development using a nutrition-sensitive approach

Micronutrient deficiencies constitute a pressing public health concern, especially in developing countries. As a dense source of bioavailable nutrients, aquatic foods can help alleviate such deficiencies. Developing aquaculture that provides critical micronutrients without sacrificing the underlying environmental resources that support these food production systems is therefore essential. Here, we address these dual challenges by optimizing nutrient supply while constraining the environmental impacts from aquaculture. Using life cycle assessment and nutritional data from Indonesia, a top aquaculture producer, we sought to identify aquaculture systems that increase micronutrient supplies and reduce environmental impacts (e.g., habitat destruction, freshwater pollution, and greenhouse gas emissions). Aquaculture systems in Indonesia vary more by environmental impacts (e.g. three order of magnitude for fresh water usage) than by nutritional differences (approximately ± 50% differences from mean relative nutritional score). Nutritional-environmental tradeoffs exist, with no single system offering a complete nutrition-environment win–win. We also find that previously proposed future aquaculture paths suboptimally balance nutritional and environmental impacts. Instead, we identify optimized aquaculture production scenarios for 2030 with nutrient per gram densities 105–320% that of business-as-usual production and with environmental impacts as low as 25% of those of business-as-usual. In these scenarios Pangasius fish (Pangasius hypophthalmus) ponds prove desirable due to their low environmental impacts, but average relative nutrient score. While the environmental impacts of the three analyzed brackish water systems range from average to high compared to other aquaculture systems, their nutritional attributes render them necessary when maximizing all nutrients except vitamin A. Common carp (Cyprinus carpio) ponds also proved essential in maximizing zinc and omega n-3, while Tilapia (Oreochromis niloticus) cages were necessary in optimizing the production of calcium and vitamin A. These optimal aquaculture strategies also reduce business-as-usual demand for wild fish-based feed by 0–30% and mangrove expansion by 0–75% with no additional expansion into inland open waters and freshwater ponds. As aquaculture production expands globally, optimization presents a powerful opportunity to reduce malnutrition rates at reduced environmental impacts. The proposed reorientation promotes UN sustainable development goals 2 (zero hunger), 3 (health), 13 (climate action) and 14 (life under water) and requires concerted and targeted policy changes.     

The fat of the land: a geography of oil and fat consumption

Lipids – or oils and fats – have attracted much attention in nutrition and medical research because of their adverse effects upon health, but the geography of lipids has received very little notice. International differences in consumption can be calculated from the Food and Agriculture Organization's Food Balance Sheets. Consumption was very low in the early nineteenth century, but increased as incomes rose and more animal foods were consumed, whilst technical advances allowed the use of a wide range of vegetable oils per capita. Consumption of total lipids is greatest in North America, Europe, Australasia and temperate South America, lowest in Asia, reflecting differences in income, although other factors are important. The sources of animal and plant lipids are discussed and their changing relative importance over time is traced. This revised version was published online in July 2006 with corrections to the Cover Date.     

我国空气污染状况及其对人体健康的影响

为了解我国空气污染状况,收集了1991～1993年全国城市污染物浓度的资料,这些污染物包括二氧化硫、氮氧化物和悬浮颗粒物,分析指出我国某些地区污染物浓度比较大,各种污染物都有不同程度的超标,然后讨论制定污染指数及相应的对人体健康的影响。