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41.
de Oliveira Aparecido Lucas Eduardo Lorençone João Antonio Lorençone Pedro Antonio Torsoni Guilherme Botega Lima Rafael Fausto dade Silva CabralMoraes José Reinaldo 《Theoretical and Applied Climatology》2022,148(3-4):899-914
Theoretical and Applied Climatology - Climate directly and indirectly influences agriculture, being the main responsible for low and high yields. Prior knowledge on yield helps coffee farmers in... 相似文献
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The point spread function of the soft X-ray telescope (SXT) aboard the Yohkoh spacecraft is a Moffat function with elliptical characteristics. This function has two parameters, a and b, that are wavelength dependent in the X-ray region of interest. Since most SXT data analysis is performed with respect to plasma temperature rather than wavelength, it is useful to spectrally average these two parameters over wavelength with temperature as the free variable. The results of this spectral averaging are given here for users of SXT data. 相似文献
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Mid-pacific mountains revisited 总被引:1,自引:0,他引:1
The Mid-Pacific Mountains are guyots whose volcanic pedestals have been constructed on a broad basement plateau, the flanks of which are downfaulted. Edifice construction may have been controlled by an orthogonal system of intersecting faults trending roughly ENE and NNW. Low amplitude gravity anomalies observed over the Mid-Pacific Mountains indicate complete Airy-Heiskanen isostatic compensation, crustal thickening, and eruption on thin elastic lithosphere. Tholeiites of the Mid-Pacific Mountains resemble lavas of Iceland and the Galapagos Islands. The orthogonal fault system, low gravity anomalies, and lava chemistry of the Mid-Pacific Mountains can be explained by eruption on or near a great ENE-trending rift system. 相似文献
46.
Jean-Marie Auzende Loren Kroenke J. -Y. Collot Y. Lafoy Bernard Pelletier 《Marine Geophysical Researches》1996,18(2-4):289-304
New bathymetric and geophysical data were collected in the region east of the island of Malaita during the SOPACMAPS II cruise of the French research vessel L'ATALANTE. This region, part of the Malaita Anticlinorium was interpreted as a piece of oceanic crust from the Ontong Java Plateau obducted over the old Solomon Islands arc during collision between the Pacific and Australian plates. It has been generally accepted that convergent motion between the Australia and Pacific plates since the Late Miocene was absorbed exclusively along the San Cristobal trench, southwest of the Solomon Islands Arc.Bathymetry, imagery, and geophysical data (magnetism, gravity, seismic) acquired during the SOPACMAPS II survey allow us to classify the successive parallel ridges mapped within the region as being recent volcanic, oceanic crust, or deformed sedimentary ridges.Seismic profiling provides evidence of successive compressive events along the Malaita margin caused by the relative motion between the Solomon Islands and the Pacific plate. The main phase of convergence probably occurred during Oligocene-early Miocene time, but some relative motion between the two domains are still being absorbed along the East Malaita boundary. The existence of active faulting in the sedimentary cover throughout the region and the present-day deformation of the outer sedimentary ridge is a good illustration of this phenomenon. 相似文献
47.
Water from the San Joaquin Delta, having chloride concentrations up to 3590 mg/L, has intruded fresh water aquifers underlying Stockton, California. Changes in chloride concentrations at depth within these aquifers were evaluated using sequential electromagnetic (EM) induction logs collected during 2004 through 2007 at seven multiple‐well sites as deep as 268 m. Sequential EM logging is useful for identifying changes in groundwater quality through polyvinyl chloride‐cased wells in intervals not screened by wells. These unscreened intervals represent more than 90% of the aquifer at the sites studied. Sequential EM logging suggested degrading groundwater quality in numerous thin intervals, typically between 1 and 7 m in thickness, especially in the northern part of the study area. Some of these intervals were unscreened by wells, and would not have been identified by traditional groundwater sample collection. Sequential logging also identified intervals with improving water quality—possibly due to groundwater management practices that have limited pumping and promoted artificial recharge. EM resistivity was correlated with chloride concentrations in sampled wells and in water from core material. Natural gamma log data were used to account for the effect of aquifer lithology on EM resistivity. Results of this study show that a sequential EM logging is useful for identifying and monitoring the movement of high‐chloride water, having lower salinities and chloride concentrations than sea water, in aquifer intervals not screened by wells, and that increases in chloride in water from wells in the area are consistent with high‐chloride water originating from the San Joaquin Delta rather than from the underlying saline aquifer. 相似文献
48.
Exposed in natural outcrops near the Duibian Village, Jiangshan County, Zhejiang Province, China, the Duibian B section is proposed as the boundary stratotype for the base of an unnamed stage termed provisionally Cambrian Stage 9. The proposed position of the GSSP is 108.12 m above the base of the Huayansi Formation, at a horizon coinciding with the first appearance of the cosmopolitan agnostoid trilobite Agnostotes orientalis. This horizon coincides also with the first appearance of the cosmopoli-tan polym... 相似文献
49.
An important ecological role ascribed to oysters is the transfer of materials from the water column to the benthos as they
feed on suspended particles (seston). This ecosystem service has been often touted as a major reason for many oyster restoration
efforts, but empirical characterization and quantification of seston removal rates in the field have been lacking. Changes
in chlorophyll a (chl a) concentrations in the water column were measured in May 2005 and June 2006 in South Carolina using in situ fluorometry and
laboratory analysis of pumped water samples taken upstream and downstream as water flowed over natural and constructed intertidal
oyster reefs. Both methods gave similar results overall, but with wide variability within individual reef datasets. In situ
fluorometer data logged at 10 to 30-s intervals for up to 1.3 h over eight different reefs (three natural and five constructed)
showed total removal (or uptake) expressed as % removal of chl a ranging from −9.8% to 27.9%, with a mean of 12.9%. Our data indicate that restored shellfish reefs should provide water-quality
improvements soon after construction, and the overall impact is probably determined by the size and density of the resident
filter feeder populations relative to water flow characteristics over the reef. The measured population-level chl a removal was converted to mean individual clearance rates to allow comparison with previous laboratory studies. Although direct
comparisons could not be made due to the small size of oysters on the study reefs (mean shell height, 36.1 mm), our calculated
rates (mean, 1.21 L h−1) were similar to published laboratory measured rates for oysters of this size. However, the wide variability in measured
removal by the oyster reefs suggests that individual oyster feeding rates in nature may be much more variable than in the
laboratory. The proliferation of ecosystem-level models that simulate the impacts of bivalves on water quality based only
on laboratory-feeding measurements underscores the importance of further research aimed at determining ecologically realistic
feeding rates for oysters in the field. Because in situ methods provide many replicate measurements quickly, they represent
a potentially powerful tool for quantifying the effects of oyster reefs, including all suspension-feeding taxa present, on
water quality. 相似文献
50.
The North Atlantic right whale (Eubalaena glacialis) faces increasing pressure from commercial shipping traffic and proposed marine renewable energy developments. Drawing upon the successful Stellwagen Bank National Marine Sanctuary model, we propose a multi-stakeholder marine spatial planning process that considers both appropriate positioning of offshore wind farms and redefining commercial shipping lanes relative to whale migration routes: placement of wind turbines within certain right whale habitats may prove beneficial for the species. To that end, it may be advisable to initially relocate the shipping lanes for the benefit of the whales prior to selecting wind energy areas. The optimal end-state is the commercial viability of renewable energy, as well as a safe shipping infrastructure, with minimal risk of collision and exposure to shipping noise for the whales. This opportunity to manage impacts on right whales could serve as a model for other problematic interactions between marine life and commercial activities. 相似文献