Asian dust: seasonal transport to the hawaiian islands

Analyses of atmospheric particles collected at Mauna Loa Observatory in Hawaii from February 1979 through September 1982 reveal strong influxes of Asian dust in the spring of each year. Concentrations of a typical crustal element, aluminum, are more than an order of magnitude greater between February and June than during the remainder of the year (71 +/- 51 versus 6.7 +/- 2.3 nanograms per cubic meter). The mass of crustal material transported during the relatively short dust episodes accounts for an average of 80 percent of the total yearly mass of atmospheric particles at 3400 meters on Mauna Loa.     

Fossil birds from the hawaiian islands: evidence for wholesale extinction by man before Western contact

Thousands of fossil bird bones from the Hawaiian Islands collected since 1971 include remains of at least 39 species of land birds that are not known to have survived into the historic period; this more than doubles the number of endemic species of land birds previously known from the main islands. Bones were found in deposits of late Quaternary age; most are Holocene and many are contemporaneous with Polynesian culture. The loss of species of birds appears to be due to predation and destruction of lowland habitats by humans before the arrival of Europeans. Because the historically known fauna and flora of the Hawaiian Islands represent only afraction of natural species diversity, biogeographical inferences about natural processes based only on historically known taxa may be misleading or incorrect.     

Eolian origin of quartz in soils of hawaiian islands and in pacific pelagic sediments

The particle-size distribution and oxygen-isotopic composition of quartz isolated from Hawaiian soils, east-central Pacific sediments, and tropospheric dusts are remarkably uniform. A common origin and tropospheric transport from continental land masses is suggested.     

舟山群岛主要岛屿间种子植物区系的差异及其影响因素

    为探究舟山群岛中的舟山岛、普陀山、中街山列岛、桃花岛、朱家尖、梅山岛、大榭岛、金塘岛、册子岛等9个主要岛屿间种子植物区系的差异及其影响因素,应用PC-ORD 4.0、SPSS 15.0软件对各岛屿区系相似性进行聚类和排序分析.结果表明:①该群岛的种子植物种类组成有一定的地理分化:舟山岛、金塘岛、梅山岛、大榭岛、册子岛的植物区系较为相近,可以归为一组,它们与整个浙江省的分布区类型也较为相似;桃花岛、朱家尖、普陀山、中街山列岛的植物区系可以归为另一组,该组具较明显的热带亲缘特征;②除了舟山岛,各岛的珍稀濒危植物的区系关系与种子植物大致一样;③种子植物种类组成受岛屿的海拔、离大陆远近和岛屿自身的海岸线长度影响较大,岛屿总面积、山地面积、平地面积、人口数量对植物区系也有一定的影响,但山地/平地面积对其影响甚微.     

Regular intervals between hawaiian earthquakes: implications for predicting the next event

During the years 1941 through 1983 five earthquake mainshocks of moderate magnitude occurred at regular intervals of 10.5 +/- 1.5 years within a 6-kilometer radius in Hawaii. It is proposed that these Kaoiki earthquakes will continue to occur at regular intervals because the strain accumulation rate and the strained volume remain constant. With appropriate instrumentation, it may be possible to refine predictions of subsequent Kaoiki earthquakes.     

Molokai fracture zone: continuation west of the hawaiian ridge

The Molokai Fracture Zone is one of the principal east-west (striking) fracture zones between California and the mid-Pacific. On the basis of bathymetry alone, it has been assumed that the zone ended abruptly east of the Hawaiian Islands. Use of correlation techniques between bathymetric features and their magnetic anomalies in the vicinity of the islands now show that structural elements of the zone cross the islands and continue westward for at least 130 kilometers. Recent volcanism and deep rift zones of the islands parallel the zone, suggesting structural correlation between the strike of the zone and the origin of recent volcanism in the islands.     

Critical periods for the effects of infantile experience on adult learning

Mice were shocked with 0.1, 0.3, or 0.5 ma of current at 2 to 3, 8 to 9, or 15 to 16 days. Handled, nonshocked and nonhandled controls were also used. In adulthood each group was split into thirds and taught an avoidance response under shock of 0.3, 0.5, or 0.7 ma. The amount of shock given during infancy and adulthood, and the age at which shock occurred, were all found to have significant effects upon learning.     

Three-dimensional simulations of plume-lithosphere interaction at the hawaiian swell

Rapid lithospheric thinning by mantle plumes has not been achieved in numerical experiments performed to date. Efficient thinning depends on small-scale instabilities that convectively remove lithospheric material. These instabilities are favored by hotter plumes or stronger temperature dependence of viscosity, and a simple scaling independent of rheology controls their onset. This scaling allows extrapolation of the results of numerical experiments to the Earth's mantle. Mantle plumes between 100 and 150 kelvins hotter than the background mantle should exhibit small-scale convective rolls aligned with the plate motion. The unusual variation in heat flow across the Hawaiian swell may be due to such instabilities. It was found that the spreading of the plume creates a downwelling curtain of material that isolates it from the rest of the mantle for distances of at least 1000 kilometers from the plume origin. This isolation has important consequences for the geochemical heterogeneity of the lithosphere and upper mantle.     

Disruption of the mauna loa magma system by the 1868 hawaiian earthquake: geochemical evidence

To test whether a catastrophic earthquake could affect an active magma system, mean abundances (adjusted for "olivine control") of titanium, potassium, phosphorus, strontium, zirconium, and niobium of historic lavas erupted from Mauna Loa Volcano, Hawaii, after 1868 were analyzed and were found to decrease sharply relative to lavas erupted before 1868. This abrupt change in lava chemistry, accompanied by a halved lava-production rate for Mauna Loa after 1877, is interpreted to reflect the disruptive effects of a magnitude 7.5 earthquake in 1868. This interpretation represents a documentable case of changes in magmatic chemical variations initiated or accelerated by a major tectonic event.     

Species number and endemism: the galapagos archipelago revisited

Regression analyses to determine plant species number are repeated for the Galápagos Islands with new data. The multiple curvilinear regression gives the best prediction of species number, with island area making the only significant contribution. The proportion of species endemic to the Galápagos is highest in the arid, transition zone and on small islands, and lowest in the littoral and mesic zones. This is explained in terms of zone-specific immigration and extinction rates and the very recent appearance of moist upland climates in the archipelago.     

Cumulate xenolith in oahu, hawaii: implications for deep magma chambers and hawaiian volcanism

The maximum depth at which large (>1000 km(3)) terrestrial mafic magma chambers can form has generally been thought to be the Moho, which occurs at a mean depth of about 35 kilometers beneath the continents and 8 kilometers beneath ocean basins. However, the presence of layers of cumulus magnesium-rich spinel and olivine and intercumulus garnet in an unusual mantle xenolith from Oahu, Hawaii, suggests that this rock is a fragment of a large magma chamber that formed at a depth of about 90 kilometers; Hawaiian shield-building magmas may pond and fractionate in such magma chambers before continuing their ascent. This depth is at or near the base of the 90-million-year-old lithosphere beneath Oahu; thus, rejuvenated stage alkalic magmas containing mantle xenoliths evidently also originate below the lithosphere.     

Critical period for effects of infantile experience on maturation of stress response

Manipulated infant rats respond to cold with depletion of adrenal ascorbic acid (AAA) significantly earlier than nonmanipulated infants. The study discussed in this report examined the critical period for infantile manipulation on the depletion of AAA. It was found that infant rats manipulated immediately following birth exhibited significant AAA depletion, whereas infants manipulated later did not exhibit depletion.     

Rare gas isotopes in hawaiian ultramafic nodules and volcanic rocks: constraint on genetic relationships

Differences in the rare gas isotopic ratios, especially the ratios of helium-3 to helium-4 and of argon-40 to argon-36, in Hawaiian ultramafic nodules and phenocrysts in volcanic rocks indicate that the nodules and phenocrysts were derived from different sources. The isotopic ratios in ultramafic nodules are similar to those in oceanic tholeiites. The phenocrysts seem to have formed in equilibrium with source materials richer in primordial components than those of the oceanic tholeiites. Mixing between the sources is quite likely.     

基础相对埋深对地基中竖向附加应力的影响

基于明德林解，给出了圆形面积均布荷载作用下，便于制定应力系数表格的竖向附加应力实用理论计算公式。讨论了基础相对埋深对地基中竖向附加应力的影响。所得结论。对改进现行地基应力与变形计算方法具有重要的理论意义和长远的实用价值。     

生态因子对豹纹鳃棘鲈受精卵孵化和仔鱼成活的影向

将豹纹鳃棘鲈(Plectropomus leopardus)受精卵在不同盐度(1％、1.4％、1.8％、2.2％、2.6％、3％、3.4％、3.8％、4.2％、4.6％)、不同温度(18、20、22、24、26、28、30、32、34、36℃)和不同光照度(0、1000、2 000、3 000、4 000、5 000、...     

Responses of hawaiian plants to volcanic sulfur dioxide: stomatal behavior and foliar injury

Hawaiian plants exposed to volcanic sulfur dioxide showed interspecific differences in leaf injury that are related to sulfur dioxide-induced changes in stomatal condutance. Species with leaves that did not close stomata developed either chlorosis or necrosis, whereas leaves of Metrosideros collina closed stomata and showed no visual symptoms of sulfur dioxide stress.