From the Management of Single Species to Ecosystem Management

2007 ◽  
pp. 225-239
Author(s):  
Jack Ward Thomas
2020 ◽  
Vol 96 (4) ◽  
pp. 617-640
Author(s):  
Andrea Dell'Apa ◽  
Joshua P Kilborn ◽  
William J Harford

Recent global improvements to fisheries sustainability have been made through the adoption of more holistic management frameworks, such as the ecosystem approach to fisheries management (EAFM) and ecosystem-based fisheries management (EBFM), and a concurrent transition from a focus on single species or stocks to multispecies and ecosystems. In the US, federal and regional fisheries management encompass multiple layers of comprehensive, ecosystem focused management strategies for living marine resources within its network of large marine ecosystems (LMEs). Here, we provide an overview for the US portion of the Gulf of Mexico large marine ecosystem (GOM-LME) by examining multiple aspects of its fishery management scheme through the lenses of EAFM, EBFM, and the integrated ecosystem assessment (IEA) framework that has been used worldwide to advise, inform, and operationalize ecosystem management. The US-GOM's fishery management and ecosystem community appears to be keeping pace with other US regional efforts. However, more tools like fishery ecosystem plans (FEPs), which are conducive to the effective integration of ecosystem considerations into fishery management processes, are needed to inform and guide the work of regional managers, decision-makers, and stakeholders. Therefore, we propose a structured planning process aimed at advancing the development and implementation of a GOM-FEP, and describe two case studies of EAFM and EBFM applications, respectively, that can help to navigate through our proposed planning process. This work offers strategic guidance and insights to support efforts of regional fishery managers to translate ecosystem management principles, approaches, and objectives into an "action oriented" FEP in the GOM-LME.


2015 ◽  
Vol 73 (4) ◽  
pp. 1042-1050 ◽  
Author(s):  
Tara E. Dolan ◽  
Wesley S. Patrick ◽  
Jason S. Link

Abstract Ecosystem management (EM) suffers from linguistic uncertainty surrounding the definition of “EM” and how it can be operationalized. Using fisheries management as an example, we clarify how EM exists in different paradigms along a continuum, starting with a single-species focus and building towards a more systemic and multi-sector perspective. Focusing on the specification of biological and other systemic reference points (SRPs) used in each paradigm and its related regulatory and governance structures, we compare and contrast similarities among these paradigms. We find that although EM is a hierarchical continuum, similar SRPs can be used throughout the continuum, but the scope of these reference points are broader at higher levels of management. This work interprets the current state of the conversation, and may help to clarify the levels of how EM is applied now and how it can be applied in the future, further advancing its implementation.


Author(s):  
Marion Hourdequin

Ecosystem management is an integrative, systems-based approach developed in response to the inadequacy of land management strategies centered on single species or resources such as timber. Contemporary ecosystem management acknowledges the dynamism of natural systems, need for ongoing adaptive learning, and importance of citizen engagement, especially in managing public lands. However, ecosystem management faces both conceptual and ethical challenges. Core concepts—such as ecosystem, stability, health, and resilience—remain difficult to define and operationalize. In addition, rapid directional changes in ecological systems have destabilized the use of historical baselines for management. One response to this challenge is to seek new moorings in an “ecosystem services” approach, focused on the role of ecological systems in supporting human interests and needs. Although ecosystem management began as a way to broaden beyond a focus on maximizing yields of particular resources, ecosystem services approaches may—ironically—reintroduce reductionistic tendencies that thwart this original goal.


Author(s):  
Mary Beth Downs ◽  
Wilson Ribot ◽  
Joseph W. Farchaus

Many bacteria possess surface layers (S-layers) that consist of a two-dimensional protein lattice external to the cell envelope. These S-layer arrays are usually composed of a single species of protein or glycoprotein and are not covalently linked to the underlying cell wall. When removed from the cell, S-layer proteins often reassemble into a lattice identical to that found on the cell, even without supporting cell wall fragments. S-layers exist at the interface between the cell and its environment and probably serve as molecular sieves that exclude destructive macromolecules while allowing passage of small nutrients and secreted proteins. Some S-layers are refractory to ingestion by macrophages and, generally, bacteria are more virulent when S-layers are present.When grown in rich medium under aerobic conditions, B. anthracis strain Delta Sterne-1 secretes large amounts of a proteinaceous extractable antigen 1 (EA1) into the growth medium. Immunocytochemistry with rabbit polyclonal anti-EAl antibody made against the secreted protein and gold-conjugated goat anti-rabbit IgG showed that EAI was localized at the cell surface (fig 1), which suggests its role as an S-layer protein.


VASA ◽  
2020 ◽  
pp. 1-6
Author(s):  
Hanji Zhang ◽  
Dexin Yin ◽  
Yue Zhao ◽  
Yezhou Li ◽  
Dejiang Yao ◽  
...  

Summary: Our meta-analysis focused on the relationship between homocysteine (Hcy) level and the incidence of aneurysms and looked at the relationship between smoking, hypertension and aneurysms. A systematic literature search of Pubmed, Web of Science, and Embase databases (up to March 31, 2020) resulted in the identification of 19 studies, including 2,629 aneurysm patients and 6,497 healthy participants. Combined analysis of the included studies showed that number of smoking, hypertension and hyperhomocysteinemia (HHcy) in aneurysm patients was higher than that in the control groups, and the total plasma Hcy level in aneurysm patients was also higher. These findings suggest that smoking, hypertension and HHcy may be risk factors for the development and progression of aneurysms. Although the heterogeneity of meta-analysis was significant, it was found that the heterogeneity might come from the difference between race and disease species through subgroup analysis. Large-scale randomized controlled studies of single species and single disease species are needed in the future to supplement the accuracy of the results.


2017 ◽  
Vol 23 (1) ◽  
Author(s):  
ASHOK KUMAR VERMA
Keyword(s):  

An attempt was made to find the ichthyo-diversity of Muntjibpur pond of Allahabad. Systematic surveys were conducted during a period of one year. A total of 13 species of fishes belonging to 12 genera, 8 families and 5 orders were identified. Siluriformes order is represented by 5 genera and 5 species while Cypriniformes order by 4 genera and 5 species. Each of the orders Clupeiformes, Osteoglossiformes and Ophiocephaliformes is represented by single genus and single species.


2020 ◽  
Vol 655 ◽  
pp. 185-198
Author(s):  
J Weil ◽  
WDP Duguid ◽  
F Juanes

Variation in the energy content of prey can drive the diet choice, growth and ultimate survival of consumers. In Pacific salmon species, obtaining sufficient energy for rapid growth during early marine residence is hypothesized to reduce the risk of size-selective mortality. In order to determine the energetic benefit of feeding choices for individuals, accurate estimates of energy density (ED) across prey groups are required. Frequently, a single species is assumed to be representative of a larger taxonomic group or related species. Further, single-point estimates are often assumed to be representative of a group across seasons, despite temporal variability. To test the validity of these practices, we sampled zooplankton prey of juvenile Chinook salmon to investigate fine-scale taxonomic and temporal differences in ED. Using a recently developed model to estimate the ED of organisms using percent ash-free dry weight, we compared energy content of several groups that are typically grouped together in growth studies. Decapod megalopae were more energy rich than zoeae and showed family-level variability in ED. Amphipods showed significant species-level variability in ED. Temporal differences were observed, but patterns were not consistent among groups. Bioenergetic model simulations showed that growth rate of juvenile Chinook salmon was almost identical when prey ED values were calculated on a fine scale or on a taxon-averaged coarse scale. However, single-species representative calculations of prey ED yielded highly variable output in growth depending on the representative species used. These results suggest that the latter approach may yield significantly biased results.


Author(s):  
R.А. Idrisov ◽  

The correct construction of agrophytocenoses on the slopes of the steppe trans-Urals helped to create maximum productivity. In the arid climate, the most productive were the double mixtures of alfalfa with brittle sitnik, wheatgrass is syd, providing an average of 41.6 and 40.2 quintals per hectare (c/ha) of hay, 32.1 and 31.0 GJ/ha OE (exchange energy per hectare), 4.5 and 4.3 quintals per hectare of boiled protein (c/ha) over 5 years. Single-species steppe ecotypes, brittle sieve and wheatgrass sieve in productivity slightly gave way to double components, providing respectively hay- 32.2 and 37.2 cents per hectare, exchange energy 22.2 and 25.7 GJ/ha, digested protein 1.93 and 2.53 c/ha. The enrichment of agrophytocense by the legume component allowed to increase the metabolic energy content to the level of 32.1 and 31.0-GJ/ha, digested protein to 4.5 and 4.3 quintals per hectare, which is 14 times the nutritional value of the metabolic energy, the digested protein is 10 times higher than the natural herb.


1996 ◽  
Author(s):  
Mark W. Brunson ◽  
Linda E. Kruger ◽  
Catherine B. Tyler ◽  
Susan A. Schroeder

Sign in / Sign up

Export Citation Format

Share Document