Developing alternatives for optimal representation of seafloor habitats and associated communities in Stellwagen Bank National Marine Sanctuary

The implementation of various types of marine protected areas is one of several management tools available for conserving representative examples of the biological diversity within marine ecosystems in general and National Marine Sanctuaries in particular. However, deciding where and how many sites to establish within a given area is frequently hampered by incomplete knowledge of the distribution of organisms and an understanding of the potential tradeoffs that would allow planners to address frequently competing interests in an objective manner. Fortunately, this is beginning to change. Recent studies on the continental shelf of the northeastern United States suggest that substrate and water mass characteristics are highly correlated with the composition of benthic communities and may therefore, serve as proxies for the distribution of biological biodiversity. A detailed geo-referenced interpretative map of major sediment types within Stellwagen Bank National Marine Sanctuary (SBNMS) has recently been developed, and computer-aided decision support tools have reached new levels of sophistication. We demonstrate the use of simulated annealing, a type of mathematical optimization, to identify suites of potential conservation sites within SBNMS that equally represent 1) all major sediment types and 2) derived habitat types based on both sediment and depth in the smallest amount of space. The Sanctuary was divided into 3610 0.5 min2 sampling units. Simulations incorporated constraints on the physical dispersion of sampling units to varying degrees such that solutions included between one and four site clusters. Target representation goals were set at 5, 10, 15, 20, and 25 percent of each sediment type, and 10 and 20 percent of each habitat type. Simulations consisted of 100 runs, from which we identified the best solution (i.e., smallest total area) and four nearoptimal alternates. We also plotted total instances in which each sampling unit occurred in solution sets of the 100 runs as a means of gauging the variety of spatial configurations available under each scenario. Results suggested that the total combined area needed to represent each of the sediment types in equal proportions was equal to the percent representation level sought. Slightly larger areas were required to represent all habitat types at the same representation levels. Total boundary length increased in direct proportion to the number of sites at all levels of representation for simulations involving sediment and habitat classes, but increased more rapidly with number of sites at higher representation levels. There were a large number of alternate spatial configurations at all representation levels, although generally fewer among one and two versus three- and four-site solutions. These differences were less pronounced among simulations targeting habitat representation, suggesting that a similar degree of flexibility is inherent in the spatial arrangement of potential protected area systems containing one versus several sites for similar levels of habitat representation. We attribute these results to the distribution of sediment and depth zones within the Sanctuary, and to the fact that even levels of representation were sought in each scenario. (PDF contains 33 pages.

A bioregional classification of the continental shelf of northeastern North America for conservation analysis and planning based on representation

Understanding how well National Marine Sanctuaries and other marine protected areas represent the diversity of species present within and among the biogeographic regions where they occur is essential for assessing their conservation value and identifying gaps in the protection of biological diversity. One of the first steps in any such assessment should be the development of clearly defined and scientifically justified planning boundaries representing distinct oceanographic conditions and faunal assemblages. Here, we propose a set of boundaries for the continental shelf of northeastern North America defined by subdivisions of the Eastern Temperate Province, based on a review and synthesis (i.e. meta-analysis) of the scientific literature. According to this review, the Eastern Temperate Province is generally divided into the Acadian and Virginian Subprovinces. Broad agreement places the Scotian Shelf, Gulf of Maine, and Bay of Fundy within the Acadian Subprovince. The proper association of Georges Bank is less clear; some investigators consider it part of the Acadian and others part of the Virginian. Disparate perspectives emerge from the analysis of different groups of organisms. Further, while some studies suggest a distinction between the Southern New England shelf and the rest of the Mid-Atlantic Bight, others describe the region as a broad transition zone with no unique characteristics of its own. We suggest there exists sufficient evidence to consider the Scotian Shelf, Gulf of Maine, Georges Bank, Southern New England, and Southern Mid-Atlantic Bight as distinct biogeographic regions from a conservation planning perspective, and present a set of proposed mapped boundaries. (PDF contains 23 pages.

Bringing a network perspective into research on technological transfers and other interorganizational relationships

International interorganizational relationships have exploded in the last decade (U.S. News and World Report, June 20, 1988: 48) and not surprisingly researchers have become increasingly interested in this phenomenon. A strong foundation of research grounded in strategic and transaction cost approaches is emerging on dyads at the organizational and industry level. This article proposes that a network perspective which considers the constellation of relationships these dyads are embedded in could enhance this research stream by bringing issues of power, resource dependence and exchange to the forefront. Applications using data on U.S./Japan linkages are used to illustrate a network approach. Implications for future research on interorganizational relationships are considered

Penetration without dependence: A network analysis of Japanese economic activity in the U.S.

Economic activity between the U.S. and Japan has skyrocketed in the last decade, yet there is little cross-industry research exploring entry patterns of multiple forms of investment. This study explores the form and occurrence of new Japanese investment across the U.S. economy in 1984. In the first part of the paper, a conceptual scheme for classifying investments is developed and then compared to the results generated from an empirical classification using structural equivalence analysis. The second part of the paper predicts and maps where the three key forms, direct investment (DI), high resource investment linkages (HRIL's), and low resources investment linkages (LRIL's) predominate. The results show that LRIL's are found primarily in less predictable environments with rapidly changing technologies. HRIL's are found in stable environments with difficult barriers to entry. DIs are found in more accessible, profitable environments, often providing suppliers for Japanese companies already established in the U.S. Implications for theory and policy are highlighted

The relationship of industry evolution to patterns of technological linkages, joint ventures, and direct investment between the U.S. and Japan

The patterns of technological linkages, joint ventures, and direct investment between U.S. and Japan were predicted for emerging, growing, maturing, and declining industries based on an analysis of the key characteristics of each stage of industry evolution and the costs and benefits of each form of resource investment. A first model predicting peak activity for technological linkages in emerging industries, joint ventures in growing industries, and direct investment in maturing industries was supported as was a second model which customized prediction for all forms at each stage of evolution. Implications and suggestions for future research are discussed

Magnetospheric lion roars

International audienceThe Equator-S magnetometer is very sensitive and has a sampling rate normally of 128 Hz. The high sampling rate for the first time allows detection of ELF waves between the ion cyclotron and the lower hybrid frequencies in the equatorial dawnside magnetosphere. The characteristics of these waves are virtually identical to the lion roars typically seen at the bottom of the magnetic troughs of magnetosheath mirror waves. The magnetospheric lion roars are near-monochromatic packets of electron whistler waves lasting for a few wave cycles only, typically 0.2 s. They are right-hand circularly polarized waves with typical amplitudes of 0.5 nT at around one tenth of the electron gyrofrequency. The cone angle between wave vector and ambient field is nearly always smaller than 1°

Fighting Against Forgetting:Remembering the Places Where My Relationship With My Father Came Into Being

When cancer took my dad’s last breath, I was left with the fear that all the dark memories of our relationship might crowd out and overshadow some of my delightful son–father memories. Haunted by the fear of forgetting all those “good” memories, focusing on where they were created, I write into being some of the beautiful moments I want to preserve. Providing examples from my work of memory, the purpose is to show that we do not need to start with dark backgrounds before brighter futures can emerge. What happens when only mundane, beautiful memories are preserved is also considered.</p

A case study of a radially polarized Pc4 event observed by the Equator-S satellite

International audienceA 16 mHz Pc4 pulsation was recorded on March 17, 1998, in the prenoon sector of the Earth's magnetosphere by the Equator-S satellite. The event is strongly localized in radial direction at approximately L = 5 and exhibits properties of a field line resonance such as an ellipticity change as seen by applying the method of the analytical signal to the magnetic field data. The azimuthal wave number was estimated as m \approx 150. We discuss whether this event can be explained by the FLR mechanism and find out that the change in ellipticity is more a general feature of a localized Alfvén wave than indicative of a resonant process

The role of marine reserves in achieving sustainable fisheries (One contribution of 15 to a Theme Issue 'Fisheries: a Future?')

Many fishery management tools currently in use have conservation value. They are designed to maintain stocks of commercially important species above target levels. However, their limitations are evident from continuing declines in fish stocks throughout the world. We make the case that to reverse fishery declines, safeguard marine life and sustain ecosystem processes, extensive marine reserves that are off limits to fishing must become part of the management strategy. Marine reserves should be incorporated into modern fishery management because they can achieve many things that conventional tools cannot. Only complete and permanent protection from fishing can protect the most sensitive habitats and vulnerable species. Only reserves will allow the development of natural, extended age structures of target species, maintain their genetic variability and prevent deleterious evolutionary change from the effects of fishing. Species with natural age structures will sustain higher rates of reproduction and will be more resilient to environmental variability. Higher stock levels maintained by reserves will provide insurance against management failure, including risk-prone quota setting, provided the broader conservation role of reserves is firmly established and legislatively protected. Fishery management measures outside protected areas are necessary to complement the protection offered by marine reserves, but cannot substitute for it