Marine protected areas in Puerto Rico: Historical and current perspectives   总被引：1，自引：0，他引：1  

Alfonso Aguilar-Perera  Michelle Schrer  Manuel Valds-Pizzini 《Ocean & Coastal Management》2006,49(12):961-975

In Puerto Rico, the environmental legislation for establishing marine protected areas (MPAs) is complex due to its current political position with the United States (US) as not only local but also federal US laws affect designations. Historically, during the Spanish rule, mangrove forests were protected for extractive reasons (i.e., charcoal) and the first protected area was established by 1918 as an Insular Forest. Currently, of the 37 MPAs recognized and investigated in this work, the vast majority (73%) are Natural Reserves, followed by Commonwealth Forests (13.5%). Most MPAs in Puerto Rico were implemented using a top-down approach (i.e., government) which follows US federal guidelines for protecting endangered species, critical habitats, and natural and cultural resources. The development of management plans for MPAs on the island is increasingly adopting a public participatory process. However, this latter process is new for the government of Puerto Rico that has not incorporated a policy based on an Integrated Coastal Management.  相似文献   

Spatial patterns of groundfish assemblages on the continental shelf of Portugal   总被引：4，自引：1，他引：4  

Gomes  Manuel C.; Serrao  Ester; de Fatima Borges  Maria 《ICES Journal of Marine Science》2001,58(3):633-647

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Microstructure measurements in natural waters: Methodology and applications   总被引：2，自引：0，他引：2  

Elena Roget  Iossif Lozovatsky  Xavier Sanchez  Manuel Figueroa   《Progress in Oceanography》2006,70(2-4):126

Modern approaches to microstructure data processing, including wavelet denoising, are discussed. The wavelet procedure is applied to small-scale shear signals before estimating the dissipation rate ε and to the temperature/density profiles used to calculate Thorpe scales. Microstructure data obtained on the Mediterranean shelf of Catalonia are used to illustrate various approaches to the Thorpe displacement calculations. It is suggested that the Weibull probability function is an appropriate model for the Thorpe scale distribution. Microstructure measurements from the upper layer of the Boadella reservoir (Catalonia, Spain) support this finding.A new analytical approximation for the 1D Panchev–Kesich spectrum is deduced and the results of ε computation are compared with spectral fitting by the widely used Nasmyth spectrum. Applying the Kraichnan spectral model to compute ε from temperature spectra in the convective-viscous sub-range is examined as an alternative to the Batchelor spectrum. Microstructure measurements taken in Lake Banyoles (Catalonia, Spain) and in the North Atlantic were used for spectral calculations.Statistical analysis of eddy K_b and thermal K_θ diffusivities measured on a shallow shelf of the Black Sea shows the importance of process-orientated domain averaging of the diffusivities in obtaining good correspondence between K_b and K_θ in active turbulent regions. In weakly turbulent, stratified interior layers, the averaged K_b and K_θ differ significantly, which may point to the inapplicability of isotropic formulae used for ε and temperature dissipation χ_θ estimates, as well as to a dependence of the mixing efficiency γ on the Richardson number or in some cases on regions of fossil turbulence.  相似文献   

Paleontology,sedimentology and paleoenvironment of a new fossiliferous locality of the Jurassic Cañadón Asfalto Formation,Chubut Province,Argentina     

Oscar F. Gallego  Nora G. Cabaleri  Claudia Armella  Wolfgang Volkheimer  Sara C. Ballent  Sergio Martínez  Mateo D. Monferran  Diego G. Silva Nieto  Manuel A. Páez 《Journal of South American Earth Sciences》2011,31(1):54-68

A new Late Jurassic assemblage of “conchostracans”, ostracods, bivalves and caddisfly cases from the locality “Estancia La Sin Rumbo”, Chubut Province (Patagonia, Argentina) is recorded. The fossils occur in the upper part of an outcropping 45 m thick volcaniclastic lacustrine sequence of yellowish tuffs and tuffites of the Puesto Almada Member, which is the upper member of the Cañadón Asfalto Formation with U/Pb age of 161 ± 3 Ma. The sequence represents one sedimentary cycle composed of a (lower) hemicycle of expansion and a (higher) hemicycle of contraction of the water body. The invertebrates lived in small freshwater bodies during the periods of expansion of the lake. The occurrence of a great number of small spinicaudatans, associated with mud-cracks, is evidence of dry climatic conditions and suggests several local mortality events. The spinicaudatan record of the fushunograptid–orthestheriid (component of the Eosestheriopsis dianzhongensis fauna) and the presence of Congestheriella rauhuti Gallego and Shen, suggest a Late Jurassic (Oxfordian to Tithonian) age. Caddisfly cases are recorded for the first time in the Cañadón Asfalto Basin.  相似文献   

The Effect of Heavy Tamping on Structured Residual Clay Site     

Rizzon  Matheus Miotto  Wagner  Alexia Cindy  Godoy  Vinicius Batista  Moreira  Eclesielter Batista  Consoli  Nilo Cesar 《Geotechnical and Geological Engineering》2021,39(7):5365-5374

This paper examines the effect of heavy tamping (dynamic compaction) on highly porous structured residual clayey soil. The aim of this study is to analyse the feasibility of this technique when applied on lightly bonded residual soil sites, which are commonly found in tropical and subtropical regions. This soil has some interesting characteristics, such as high fine grain soil percentages (56% clay and 22% silt), a plastic index of 11%, high porosity (initial void ratio of 1.21), high hydraulic conductivity (about 10^?5 m/s) and a high stiffness at small strains (E?=?49.2-MPa). The research involves field [Cone Penetration Test (CPT) and the dynamic compaction] and laboratory (triaxial tests, characterization and hydraulic conductivity) investigation. According to laboratory tests, the void ratio decreased to 0.96, hydraulic conductivity decreased to 2.8?×?10^?7 m/s, the effective peak friction angle (?′) increased from 30.5° (in natural conditions) to about 35.5°, and the triaxial stiffness at small strains decreased to E?=?20-MPa due to dynamic compaction. CPT results have shown an improved depth in which CPT tip strength (q_t) increased from nearly 650-kPa to an average of 1700-kPa and CPT sleeve friction (f_s) increased from approximately 50-kPa to about 130-kPa. Horizontal displacements were observed up to about 4.0 m of depth (approximately the same depth at which CPT results showed soil improvement). It was concluded that heavy tamping reduces soil voids and substantially increases soil strength, but also breaks soil structure and decreases soil stiffness. It is thus not a suitable ground improvement solution for highly porous structured residual clayey soil.

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Artificial Marine Micro‐Reserves Networks (AMMRNs): an innovative approach to conserve marine littoral biodiversity and protect endangered species          下载免费PDF全文

José C. García‐Gómez  José M. Guerra‐García  Free Espinosa  Manuel J. Maestre  Georgina Rivera‐Ingraham  Darren Fa  Alexander R. González  Aurora Ruiz‐Tabares  Carlos M. López‐Fé 《Marine Ecology》2015,36(3):259-277

Coastal engineering works, especially the outer breakwaters of ports where environmental conditions are usually good, often constitute new habitats for marine littoral species. Their potential indirect contribution to the regeneration and conservation of protected species opens up a new perspective in protection of marine biodiversity. This is particularly true when these works harbour, as we show here, important reproductive populations of species that are threatened or even in danger of extinction. We provide integrated data on protected marine species in Southern Iberia established on different substrata (quarried dolomitic rocks, concrete cubic blocks, concrete tetrapods and vertical concrete walls) that are used in the construction of artificial levees that could potentially be Artificial Marine Micro‐Reserves (AMMRs). We also present the first evidence of the ‘reserve effect’ in potential AMMRs and we discuss the need for the creation of AMMRs including their effective networking (AMMRNs), supporting data for which has been observed by studying coastal facilities subjected to strict access restrictions (for security reasons, not conservation). These facilities have acted as valuable proxies and, in reality, potentially act as AMMRs, as well as having a role in helping to detect and control invasive species. We discuss the ecological engineering aspects related to the design and type of materials used in coastal constructions with a view to aiding the integration of these into existing coastal ecosystems as well as promoting greater settlement of species and therefore increases in biodiversity. Finally, the environmental implications of AMMRNs within the future implementation strategy of the Water Framework Directive 2000/60 EC are also discussed.  相似文献   

SHPTS: towards a new method for generating precise global ionospheric TEC map based on spherical harmonic and generalized trigonometric series functions   总被引：12，自引：4，他引：8  

Zishen Li  Yunbin Yuan  Ningbo Wang  Manuel Hernandez-Pajares  Xingliang Huo 《Journal of Geodesy》2015,89(4):331-345

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The effect of the "Prestige" oil spill on the plankton of the N-NW Spanish coast     

Varela M  Bode A  Lorenzo J  Alvarez-Ossorio MT  Miranda A  Patrocinio T  Anadón R  Viesca L  Rodríguez N  Valdés L  Cabal J  Urrutia A  García-Soto C  Rodríguez M  Alvarez-Salgado XA  Groom S 《Marine pollution bulletin》2006,53(5-7):272-286

Chlorophyll, primary production, zooplankton biomass and the species composition of phytoplankton and zooplankton were studied in 2003, after the Prestige shipwreck. The information obtained was compared to previous data series available for the area affected by the spill. A large data series on plankton variables for the N-NW Spanish coast existed, and therefore a realistic evaluation of the effects by comparison with the range of natural variability could be carried out. We emphasized the evaluation of impact during the spring bloom, the first important biological event after the spill. Some minor changes were observed occasionally, but they did not show any clear pattern and were more related to the natural variability of the ecosystem than to effect of the spill. Plankton community structure did not undergo any changes. Only a few species were more abundant during spring 2003 than in previous years. No significant changes were detected in the planktonic community during productive periods, such as the spring bloom and the summer blooms related to intrusions of East North Atlantic Central Waters. The lack of evidence of the effects of the spill on planktonic communities is discussed in terms of the characteristics of the fuel, the high dynamics of the water masses, the biological mechanisms through which the fuel from the surface waters is transferred to the sea floor and, particularly, the influence of the natural variability by means of large and meso-scale hydrographic processes in the area under study. At the present time it is not possible to determine any minor effects the spill may have had on the plankton owing to the great variability of the planktonic cycles and the short-term impact of the oil from the Prestige on the pelagic system.  相似文献   

Assessment of contamination by polychlorinated biphenyls and aliphatic and aromatic hydrocarbons in sediments of the Santos and São Vicente Estuary System, São Paulo, Brazil   总被引：1，自引：0，他引：1  

Bícego MC  Taniguchi S  Yogui GT  Montone RC  Moreira da Silva DA  Lourenço RA  de Castro Martins C  Sasaki ST  Pellizari VH  Weber RR 《Marine pollution bulletin》2006,52(12):1804-1816

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A semi-analytical solution for the three-dimensional advection–diffusion equation considering non-local turbulence closure     

M.T. Vilhena  C.P. Costa  D.M. Moreira  T. Tirabassi   《Atmospheric Research》2008,90(1):63-69

Atmospheric air pollution turbulent fluxes can be assumed to be proportional to the mean concentration gradient. This assumption, along with the equation of continuity, leads to the advection–diffusion equation. Moreover, large eddies are able to mix scalar quantities in a manner that is counter to the local gradient. In this work we present a semi-analytical solution for the three-dimensional steady-state advection–diffusion equation, considering non-local turbulence closure using the Generalized Integral Advection Diffusion Multilayer Technique (GIADMT). We report some examples of applications of the new solution for two different datasets and for a water tank experiment.  相似文献