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Seismic generated sea waves from the September 14, 1995, Mexico earthquake are favored over the waves generated by hurricane Ismael to be the cause of the increase in seiche amplitudes in Manzanillo and Cabo San Lucas tide stations. The arguments are based on travel time computations from the seismic source and the moving meteorological source. A relatively sudden increase in seiche amplitudes is consistent with the arrival time of the seismic tsunami, and previously existent background is likely produced by incoming waves from the hurricane. 相似文献
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Salvador Pueyo 《Climatic change》2007,82(1-2):131-161
Here I present a new approach to forecasting the effects of climate change on catastrophic events, based on the ‘self-organised
criticality’ concept from statistical physics. In particular, I develop the ‘self-organised critical fuel succession model’
(SOCFUS), which deals with wildland fires. I show that there is good agreement between model and data for the response pattern
of the whole fire size statistical distribution to weather fluctuations in a boreal forest region. I tentatively predict the
fire regime in this region for an instance of possible climate change scenario. I show that the immediate response is sharper
than usually thought, but part of the added burning rate might not persist indefinitely. A large fraction of the extra burning
in the transition period is likely to be concentrated in a few ‘climate change fires’, much larger than the largest fires
that could currently occur. I also suggest that the major fire events recently observed in some tropical rainforest regions
belong to a qualitatively different, even more abrupt type of response, which is also predicted by the model.
Electronic supplementary material Electronic supplementary material is available for this article at 相似文献
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Salvador E. Lluch-Cota Eugenio A. Aragón-Noriega David Aurioles-Gamboa Richard C. Brusca Roberto Cortés-Altamirano Alfonso Esquivel-Herrera Michel E. Hendrickx Hugo Herrera-Cervantes Miguel Lavín Daniel B. Lluch-Cota Silvio G. Marinone Sofia Ortega-García Alejandro Parés-Sierra Mauricio Ramírez-Rodríguez Richard A. Schwartzlose Arturo P. Sierra-Beltrán 《Progress in Oceanography》2007,73(1):1-26
The Gulf of California is unique because of its geographical location and conformation. It hosts diverse ecosystems and important fisheries that support industry and provide livelihood to coastal settlements. It is also the site of interests and problems, and an intense interaction among managers, producers, and conservationists. In this report, we scrutinize the abiotic (hydrography, climate, ocean circulation, and chemistry) and biotic (phyto- and zooplankton, fish, invertebrates, marine mammals, birds, and turtles) components of the marine ecosystem, and some particular aspects of climate variability, endemisms, harmful algal blooms, oxygen minimum layer, and pollution. We also review the current conditions and conflicts around the main fisheries (shrimp, small and large pelagic fishes, squid, artisanal and sportfishing), the most important human activity in the Gulf of California. We cover some aspects of management and conservation of fisheries, especially the claimed overexploitation of fish resources and the ecosystems, and review proposals for creating networks of marine protected areas. We conclude by identifying main needs for information and research, particularly the integration of data bases, the implementation of models and paleoreconstructions, establishment of monitoring programs, and the evaluation of fishing impacts and management actions. 相似文献
37.
Leopoldo Martínez Nieto Gassan Hodaifa Salvador Rodríguez José A. Giménez Javier Ochando 《洁净——土壤、空气、水》2011,39(10):949-955
Flocculation and sedimentation of particles are essential to many environmental and industrial processes. Solid–liquid separation in olive‐oil mill wastewater treatment by means of Fenton system is the key to work continuously and maintain a constant outlet flow of clarified water at the end of the oxidation process. Natural sedimentation is not capable to eliminate the sludge formed. The efficiency of flocculation operation using different flocculants as QG‐2001, QG‐2002, DQGALFLOC‐130H, and Nalco‐77171 was investigated. The optimum dosage of each flocculant, 150, 2.5, 66, and 6 mg dm?3, respectively, was determined. The results revealed that the best flocculant was Nalco‐77171, which determined 13.5% v/v final sludge separation and 86.5% v/v final clarified water obtained. Kinetics of sludge removal in the transition zone was adjusted to power law, v/v0 = Ktε, where the exponent, ε, varied in the range 0.141–0.670. 相似文献
38.
The term Tertiary, subdivided into the Paleogene and Neogene, is traditionally used to represent the interval of geological time between the Cretaceous and Quaternary. In the 1990s, however, the Neogene and Paleogene were ratified by the International Union of Geological Sciences as periods/systems of the Cenozoic Era/Erathem, leaving the Tertiary officially undefined. The Tertiary nonetheless remains a formal term that has never been officially eliminated, and its widespread use today implies a long future. 相似文献
39.
Sedimentology of Quaternary perched springline and paludal tufas: criteria for recognition, with examples from Guadalajara Province, Spain 总被引:2,自引:0,他引:2
Martyn Pedley Juan Antonio González Martín† Salvador Ordóñez Delgado‡ MªÁngeles García Del Cura§ 《Sedimentology》2003,50(1):23-44
Outcrop‐scale geometries and bed relationships of ambient temperature freshwater carbonates are poorly understood because many described tufas have been dismantled by erosion and present only part of a particular depositional model. At the field scale, four end‐member models encompass the tufa continuum: (1) perched springline; (2) paludal; (3) fluvial; and (4) lacustrine tufas. Individual bed types can occur with variable dominance within several of these models, but one or more beds are characteristically dominant only within a single tufa model, so it can be differentiated from relatively isolated outcrop fragments. Two models (perched springline tufas and paludal tufas) are known in outline only in the literature despite being present within the Quaternary deposits of most karstic regions. Perched springline tufas generally form lobate, fan‐shaped mound morphologies on hillslopes and develop from single or multiple spring resurgences. Mature deposits show a subhorizontal top and a steep face on the downflow side. The steep outer zones of tufa mounds may be developed into cascades with moss curtains or can be dominated by shallow rimstone pools according to face angle. Tufa deposits lying downslope of the mounds are usually detrital in nature, especially if some dismantling of the mound has occurred. The relatively thin subhorizontal lobe‐top deposits commonly contain organic‐rich deposits. Paludal tufas develop predominantly in waterlogged valley bottom situations, where line‐sourced waters emerge from valley side and bottom aquifers. Lime mud precipitation predominates in these sites. Mud is deposited as subhorizontal laminites that thin towards the valley axis and downstream of resurgences. Tufa spring‐mounds may form where lesser volumes of water are involved. Individual tussocks (phytoherm cushions) of grasses and rushes are the most diagnostic feature of the model, but sapropels and peats may be intercalated. Diagenesis in both models is rapid. Lithification of individual beds is virtually instantaneous and always occurs before the decay of the associated living vegetation. The resulting highly porous and permeable fabrics remain fresh in Holocene tufas, but aggrading neomorphism and partial spar infill of vegetation moulds is common in older deposits. Dissolution in many perched springline tufas is small scale. Many large cavities are primary, but with later coatings of speleothems. Early removal of organics from paludal tufas is responsible for autobrecciation and differential compaction. 相似文献
40.
Distribution and abundance of the Pacific sardine (Sardinops sagax) in the Gulf of California and their relation with the environment 总被引:1,自引:0,他引:1
Manuel O. Nevrez-Martínez Daniel Lluch-Belda Miguel A. Cisneros-Mata J. Pablo Santos-Molina Ma. De los Angeles Martínez-Zavala Salvador E. Lluch-Cota 《Progress in Oceanography》2001,49(1-4)
In 1989–90 the small pelagic fishery of the Gulf of California began to show a very marked decline in the catch of its main component, the Pacific sardine (Sardinops sagax). The catch plummeted from 292,000 t in 1988–89 to 7000 t in 1991–92 and 1992–93. This caused a serious economic crisis in the local fishery fleet and industry, and resulted in the loss of 3000 jobs. In 1993–94 the fishery showed signs of recovery as the abundance of the Pacific sardine began to recover. The catch improved to 128,000 t in 1993–94 and further to 215,000 t in 1996–97. In trying to understand this great variability, we proposed the hypothesis that the distribution and the abundance of the Pacific sardine of the Gulf of California is determined by the wind patterns (upwelling) and the sea surface temperature. The results of analyzing data from 25 cruises showed the period of low relative abundance between 1990 and 1993 and one of high abundance between 1993 and 1996. The range of the sardine's distribution expanded as its abundance increased and contracted when abundances were low. The relationship between the abundances of the sardine and environmental variables proved to nonlinear and bell-shaped. The adjusted pattern explained 78.8% of the variability of the sardine abundance. The highest abundance are produced by moderate upwelling (13–18 m3s−1 per 10 m of coastline) and sea surface temperatures of between 19°C and 25°C. 相似文献