Differing trophic niches of three French stygobionts and their implications for conservation of endemic stygofauna

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Hazards of managing disparate species as a pooled complex: A general problem illustrated by two contrasting examples from Hawaii

Surprisingly little published information exists on the pros and cons of managing extracted resources that are pooled as compound taxa such as species complexes. Current fisheries management includes many species complexes; in Hawaii, this includes two taxa of species pooled at subfamily and higher levels. These include seven species of parrotfishes (Scarinae, Labridae) and a seven‐species ‘bottomfish’ complex (the ‘Deep‐7’: comprising six species of snappers [Etelinae, Lutjanidae] and a single species of grouper [Epinephelidae]). Recent research on key vital rates (growth, reproduction) for major species in both taxa indicates that these complexes consist of species with disparate life histories. Species in the parrotfish taxon exhibit fast to very fast growth and short to moderate longevities, whilst Deep‐7 bottomfishes exhibit moderate to very slow growth and long to very long lifespans. These data clearly indicate that, although pooling species is a tempting default option in data‐poor situations, it is at best a necessary evil to be avoided when sufficient data on the demographics of component species become available. Pooling species is especially problematic when the ecosystem effects of extracting functionally dominant species should be an important management consideration in addition to that of species demographics. Assessments that recognize and quantify the ecosystem importance of habitat engineers and other ecological dominants could substantively improve management of species complexes. Ultimately, complexes of resource species need to be evaluated and managed based on many, sometimes conflicting and sometimes reinforcing, but always careful considerations such as those contrasted herein between the parrotfishes and bottomfishes of Hawaii.     

Realizing the potential of trait‐based approaches to advance fisheries science

Analysing how fish populations and their ecological communities respond to perturbations such as fishing and environmental variation is crucial to fisheries science. Researchers often predict fish population dynamics using species‐level life‐history parameters that are treated as fixed over time, while ignoring the impact of intraspecific variation on ecosystem dynamics. However, there is increasing recognition of the need to include processes operating at ecosystem levels (changes in drivers of productivity) while also accounting for variation over space, time and among individuals. To address similar challenges, community ecologists studying plants, insects and other taxa increasingly measure phenotypic characteristics of individual animals that affect fitness or ecological function (termed “functional traits”). Here, we review the history of trait‐based methods in fish and other taxa, and argue that fisheries science could see benefits by integrating trait‐based approaches within existing fisheries analyses. We argue that measuring and modelling functional traits can improve estimates of population and community dynamics, and rapidly detect responses to fishing and environmental drivers. We support this claim using three concrete examples: how trait‐based approaches could account for time‐varying parameters in population models; improve fisheries management and harvest control rules; and inform size‐based models of marine communities. We then present a step‐by‐step primer for how trait‐based methods could be adapted to complement existing models and analyses in fisheries science. Finally, we call for the creation and expansion of publicly available trait databases to facilitate adapting trait‐based methods in fisheries science, to complement existing public databases of life‐history parameters for marine organisms.     

Ecosystems say good management pays off

Understanding the strengths and weaknesses of alternative assessment methods, harvest strategies and management approaches are an important part of operationalizing single‐species and ecosystem‐based fisheries management. Simulations run using two variants of a whole‐of‐ecosystem model for the Southern and Eastern Scalefish and Shark Fishery (SESSF) area shows that (a) data‐rich assessments outperform data‐poor assessments for target species and that this performance is reflected in the values of many system‐level ecosystem indicators; (b) ecosystem and multispecies management outperforms single‐species management applied over the same domain; (c) investment in robust science‐based fisheries management pays dividends even when there are multiple jurisdictions, some of which are not implementing effective management; and (d) that multispecies yield‐oriented strategies can deliver higher total catches without a notable decline in overall system performance, although the resulting system structure is different to that obtained with other forms of ecosystem‐based management.     

基于PSR模型的云贵高原湿地生态系统健康评价

威宁草海湿地生态系统健康对我国云贵高原生态安全格局建设具有重要意义。为了保护高原湿地威宁草海的基本生态系统服务功能,促进其生态系统健康发展,通过对威宁草海湿地的生态系统健康进行评价,为湿地生态恢复和环境保护提供决策支持。利用PSR(Pressure-State-Response)模型框架,从压力(P)、状态(S)和响应(R)3个方面建立评价指标体系,采用熵权法和模糊数学法建立评价模型,把草海湿地生态系统健康分为"很健康、健康、较健康、不健康、疾病"5个等级。结果表明,威宁草海湿地生态系统健康属于"不健康"等级,隶属度值为0.2934、0.3415、0.2061、0.1077、0.0513;其中,压力要素为"疾病"等级,隶属度值为0.4323、0.2862、0.1768、0.0241、0.0806;状态和响应要素均为"不健康"等级,状态要素隶属度值为0.2202、0.3174、0.2361、0.1128、0.1135,响应要素隶属度值为0.1534、0.4273、0.2307、0.0866、0.1020。压力要素的影响因素主要包括人口过多、环保压力大、化肥施用强度大、农药施用多;状态要素的影响因素主要包括湿地流域保水能力差、水量稳定性低、植被覆盖率不高、水土流失严重、土地生产力下降;响应要素的影响因素主要包括地保护意识不强、环保投入少、污水处理率低、物质生活指数不高。在草海生态系统建设过程中,应控制人口增长、减少农药和化肥施用量、提高植被覆盖率、治理水土流失。     

Changing how we approach fisheries: A first attempt at an operational framework for ecosystem approaches to fisheries management

The increasing need to account for the many factors that influence fish population dynamics, particularly those external to the population, has led to repeated calls for an ecosystem approach to fisheries management (EAFM). Yet systematically and clearly addressing these factors, and hence implementing EAFM, has suffered from a lack of clear operational guidance. Here, we propose 13 main factors (shift in location, migration route or timing, overfishing (three types), decrease in physiology, increase in predation, increase in competition, decrease in prey availability, increase in disease or parasites and a decline in habitat quality or habitat quantity) that can negatively influence fish populations via mechanisms readily observable in ~20 population features. Using these features as part of a diagnostic framework, we develop flow charts that link probable mechanism(s) underlying population change to the most judicious management actions. We then apply the framework for example case studies that have well‐known and documented population dynamics. To our knowledge, this is the first attempt to provide a clearly defined matrix of all the probable responses to the most common factors influencing fish populations, and to examine possible diagnostics simultaneously, comparatively and relatively in an attempt to elucidate the most probable mechanisms responsible. The framework we propose aims to operationalize EAFM, thereby not only better diagnosing factors influencing fish populations, but also suggesting the most appropriate management interventions, and ultimately leading to improved fisheries. We assert the framework proposed should result in both better use of limited analytical and observational resources and more tailored and effective management actions.     

A model of a hall for a workshop of metasynthetic engineering

A hall for a workshop of metasynthetic engineering (HWME) is constructed based on network services, in which the expert, machinery and knowledge systems are combined with services. This hall is an expansion of the traditional workshop hall. The     

Impact of plant community structure and its diversity on richness and abundance of arthropod aphidophagous natural enemy community

Arthropod natural enemies (ANEs) play an indispensable role in maintaining the balance for plant communities that also significantly affects the ANE diversities not only by supporting herbivorous prey, but also by providing habitats and floral food resources. Studying the diversity of ANEs is thus vital to develop an understanding of sustainable pest control. Relationships of the vegetation diversity (including richness, coverage, and Shannon–Wiener diversity) with associated arthropod aphidophagous natural enemies (AANEs) and their groups under Pinus tabuliformis of different distances were analyzed by non-metric multidimensional scaling (metaMDS). Our results indicated that the vegetation richness affects AANEs at a small scale, while the vegetation structure affects it at a large scale. The richness and abundance of AANEs and the abundance of green lacewings (GLs) and aphid parasitoids (APs) were positively related to neighboring tree richness. But the richness of AANEs and aphidophagous ladybirds (ALs) were negatively associated with nearby tree coverage, as well as AANE richness with close-up shrub coverage, while the abundance of AANEs, ALs, and GLs possessed a negative and hump-shaped relationship with nearby tree coverage, as well as the abundance of AANEs and GLs with close-up shrub coverage. When tree and shrub layers each had approximately half coverage within a vegetation structure, the richness and abundance of AANEs were highest. Similarly, the richness and abundance of AANEs were positively related to neighboring blooming plant richness. However, the richness of AANEs and ALs, and the abundance of AANEs, AL, GL, and APs had a positive association either with the coverage or with the Shannon–Wiener diversity of close-up blooming plants. Half coverage of the tree and shrub layer combined with higher diversities (richness, coverage, and Shannon–Wiener diversity) of blooming plants resulted in low aphid density. The results provide a basis for effectively improving AANE diversity.     

安庆都市圈生态系统服务权衡与协同

为厘清区域发展特征、优化区域布局、实现生态转型和绿色可持续发展,研究生态系统服务之间的权衡和协同关系是发展的基础.本研究以安庆都市圈为研究对象,运用空间计量法估算安庆都市圈的水源涵养、土壤保持、NPP服务和食物供给等4种生态系统服务,分析不同生态系统服务之间的权衡与协同关系,并运用CA-Markov模型预测203 0年...     

Fish movement and habitat use depends on water body size and shape

Abstract –  Home ranges are central to understanding habitat diversity, effects of fragmentation and conservation. The distance that an organism moves yields information on life history, genetics and interactions with other organisms. Present theory suggests that home range is set by body size of individuals. Here, we analyse estimates of home ranges in lakes and rivers to show that body size of fish and water body size and shape influence home range size. Using 71 studies including 66 fish species on five continents, we show that home range estimates increased with increasing water body size across water body shapes. This contrasts with past studies concluding that body size sets home range. We show that water body size was a consistently significant predictor of home range. In conjunction, body size and water body size can provide improved estimates of home range than just body size alone. As habitat patches are decreasing in size worldwide, our findings have implications for ecology, conservation and genetics of populations in fragmented ecosystems.