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151.
Inés Ibá?ez Richard B. Primack Abraham J. Miller-Rushing Elizabeth Ellwood Hiroyoshi Higuchi Sang Don Lee Hiromi Kobori John A. Silander 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2010,365(1555):3247-3260
As a consequence of warming temperatures around the world, spring and autumn phenologies have been shifting, with corresponding changes in the length of the growing season. Our understanding of the spatial and interspecific variation of these changes, however, is limited. Not all species are responding similarly, and there is significant spatial variation in responses even within species. This spatial and interspecific variation complicates efforts to predict phenological responses to ongoing climate change, but must be incorporated in order to build reliable forecasts. Here, we use a long-term dataset (1953–2005) of plant phenological events in spring (flowering and leaf out) and autumn (leaf colouring and leaf fall) throughout Japan and South Korea to build forecasts that account for these sources of variability. Specifically, we used hierarchical models to incorporate the spatial variability in phenological responses to temperature to then forecast species'' overall and site-specific responses to global warming. We found that for most species, spring phenology is advancing and autumn phenology is getting later, with the timing of events changing more quickly in autumn compared with the spring. Temporal trends and phenological responses to temperature in East Asia contrasted with results from comparable studies in Europe, where spring events are changing more rapidly than are autumn events. Our results emphasize the need to study multiple species at many sites to understand and forecast regional changes in phenology. 相似文献
152.
Feeding habits and gill raker morphology of three planktivorous pelagic fish species off the coast of northern and western Kyushu in summer 总被引:2,自引:0,他引:2
Feeding habits and gill raker morphology were examined for the three major planktivorous pelagic fishes, Japanese anchovy Engraulis japonicus , Pacific round herring Etrumeus teres and Japanese jack mackerel Trachurus japonicus , off the northern and western coasts of Kyushu, in the north‐eastern part of the East China Sea in the summer months of 2001. Using fishes in the same size range (80–140 mm, standard length), the stomach contents of the three fish species were compared. The diet of the Japanese anchovy mainly consisted of Oncaeidae copepods, while the diets of the Pacific round herring and Japanese jack mackerel were dominated by calanoid copepods at all stations. Comparisons between prey size in the stomach, zooplankton size in the water and gill raker morphology suggested that the stomach contents of the three species were characterized mainly by the difference in the feeding behaviour between Japanese anchovy (filter‐feeding) and the other two species (particulate‐feeding), rather than by the difference in the morphology of feeding apparatus only. It was concluded that behavioural adaptations in the feeding of these pelagic fishes brought about trophic partitioning to some degree in this pelagic ecosystem in summer. Although the diets of these three species overlapped to some extent, there was still little likelihood of competition between the Japanese anchovy and the other two species. The potential for competition between the Pacific round herring and the Japanese jack mackerel is discussed. 相似文献
153.
Taton A Grubisic S Balthasart P Hodgson DA Laybourn-Parry J Wilmotte A 《FEMS microbiology ecology》2006,57(2):272-289
For the first time, the cyanobacterial diversity from microbial mats in lakes of Eastern Antarctica was investigated using microscopic and molecular approaches. The present study assessed the biogeographical distribution of cyanobacteria in Antarctica. Five samples were taken from four lakes spanning a range of different ecological environments in Larsemann Hills, Vestfold Hills and Rauer Islands to evaluate the influence of lake characteristics on the cyanobacterial diversity. Seventeen morphospecies and 28 16S rRNA gene-based operational taxonomic units belonging to the Oscillatoriales, Nostocales and Chroococcales were identified. The internal transcribed spacer was evaluated to complement the 16S rRNA gene data and showed similar but more clear-cut tendencies. The molecular approach suggested that potential Antarctic endemic species, including a previously undiscovered diversity, are more abundant than has been estimated by morphological methods. Moreover, operational taxonomic units, also found outside Antarctica, were more widespread over the continent than potential endemics. The cyanobacterial diversity of the most saline lakes was found to differ from the others, and correlations between the sampling depth and the cyanobacterial communities can also be drawn. Comparison with database sequences illustrated the ubiquity of several cyanobacterial operational taxonomic units and their remarkable range of tolerance to harsh environmental conditions. 相似文献
154.
Use of wetlands at the mouth of the Yangtze River by shorebirds during spring and fall migration 总被引:1,自引:0,他引:1
Zhen-Ming Ge Tian-Hou Wang Xiao Yuan Xiao Zhou Wen-Yu Shi 《Journal of Field Ornithology》2006,77(4):347-356
ABSTRACT. The mouth of the Yangtze River is an important stopover site for migratory shorebirds using the East Asian-Australasian Flyway. From 1984 to 2004, we censused and banded shorebirds and monitored hunting activities at the mouth of the Yangtze River to understand how shorebirds used the study area. Counts and banding data revealed greater numbers of shorebirds at the mouth of the Yangtze River during northward migration (spring) than during southward migration (fall), with ratios varying from 1.5:1 to 7.2:1 at different sites from 1984 to 2005. The most common species observed during spring (northward) migration were Great Knots ( Calidris tenuirostris ), Red Knots ( Calidris canutus ), Bar-tailed Godwits ( Limosa lapponica ), Sharp-tailed Sandpipers ( Calidris acuminata ), and Red-necked Stints ( Calidris ruficollis ). During spring 2003–2004, 96.98% of the shorebirds observed were adults (ASY or older) and 3% were after hatching-year and second-year birds (AHY or SY). In contrast, almost all (94.73%) birds counted during the fall were hatching-year (HY) birds. These results indicate that adult shorebirds either use a different migration route during fall migration or use the same route, but do not stop at the mouth of the Yangtze River. HY birds, however, may depend on the coastal stopover sites for feeding during their first southward passage. 相似文献
155.
Integrated Modeling and its Potential for Resolving Conflicts between Conservation and People in the Rangelands of East Africa 总被引:1,自引:0,他引:1
Kathleen A. Galvin Philip K. Thornton Joana Roque de Pinho Jennifer Sunderland Randall B. Boone 《Human ecology: an interdisciplinary journal》2006,34(2):155-183
A major challenge for contemporary conservation policies and practices is formulating workable compromises between wildlife conservation and the people who live with wildlife. We strongly support the view that anthropology has a critical role to play in contributing to our understanding of human-environment interactions. The study of complex biophysical and human systems can be greatly assisted by appropriate simulation models that integrate what is known about ecological and human decision-making processes. We have developed an integrated modeling system for assessing scenarios in the Ngorongoro Conservation Area in northern Tanzania to modify the situation there to improve human welfare without compromising conservation value. We present the results of some scenarios that indicate that the current situation there is not sustainable, and that tough policy decisions need to be taken if household well-being of the pastoralists who live there is to be improved or even sustained. 相似文献
156.
Li SL Yamamoto T Yoshimoto T Uchihi R Mizutani M Kurimoto Y Tokunaga K Jin F Katsumata Y Saitou N 《Human genetics》2006,118(6):695-707
We have analyzed 105 autosomal polymorphic short tandem repeat (STR) loci for nine East and South-eastern Asian populations
(two Japanese, five Han Chinese, Thai, and Burmese populations) and a Caucasian population using a multiplex PCR typing system.
All the STR loci are genomewide tetranucleotide repeat markers of which the total number of observed alleles and the observed
heterozygosity were 756 and 0.743, respectively, for Japanese populations. Phylogenetic analysis for these allele frequency
data suggested that the Japanese populations are more closely related with southern Chinese populations than central and/or
northern ones. STRUCTURE program analysis revealed the almost clearly divided and accountable population structure at K=2–6, that the two Japanese populations always formed one group separated from the other populations and never belong to different
groups at K≥3. Furthermore, our new allele frequency data for 91 loci were analyzed with those for 52 worldwide populations published
by previous studies. Phylogenetic and multidimensional scaling (MDS) analyses indicated that Asian populations with large
population size (six Han Chinese, three Japanese, two Southeast Asia) formed one distinct cluster and are closer to each other
than other ethnic minorities in east and Southeast Asia. This pattern may be the caviar of comparing populations with greatly
differing population sizes when STR loci were analyzed. 相似文献
157.
Harutaka Sakai Hideo Sakai Rie Fujii Bishal Nath Upreti 《Palaeogeography, Palaeoclimatology, Palaeoecology》2006,241(1):16-27
Core-drilling project carried out in the southern margin of the Kathmandu Basin revealed that muddy debris flow deposits dammed up the Proto-Bagmati river to form the Paleo-Kathmandu Lake during the Jaramillo subchron from 1.07 to 0.97 Ma. Subsequent deposition of the alluvial fanglomerate, derived from the uplifting Mahabharat Range to the south, raised the dam deepening the lake-water. After 1 Ma, in the southern part of the basin, palaeo-current directions changed from southward to northward and deposition of gneissose and granitic detritus are replaced by meta-sediments derived from the Mahabharat Range.During the same time, at about 1 Ma, the boulder conglomerates were deposited on top of the Siwalik Group as piggy-back basins in front of an intra-basinal high, along the Main Dung Thrust in Nepal and NW India. Onset of movement of the Main Dung Thrust is dated back to 3 to 2.4 Ma [Mugnier, J.L., Huyge, P., Leturmy, P., Jouanne, F., 2003, Episodicity and rates of thrust-sheet motion in the Himalayas, Western Nepal. Am. Assoc. Petrol. Geol., Mem. 82, 1-24]. The Main Frontal Thrust is most active at present suggesting that imbricated structure of the Siwalik Group was formed by convergence of the Indian plate during the last 3 myr. The accretionary wedge of the Siwalik Group, stacked beneath the Main Boundary Thrust, might have started to jack up the frontal range of the Lesser Himalaya since 1 Ma.Coeval uplift and erosion of the frontal range of the Lesser Himalaya and the intra-basinal high in the Siwalik since 1 Ma are possible causes of an abrupt increase in both sedimentation rate and grain size of detrital quartz, and changes in composition of clay minerals, recorded in the sediments of the Bengal Deep Sea Fan at 0.9 Ma. 相似文献
158.
Assefa Z 《Journal of human evolution》2006,51(1):50-75
The Middle Stone Age (MSA) sediments of Porc-Epic Cave near Dire Dawa, Ethiopia, have produced a large assemblage of archaeofaunal remains dating to the later periods of the Late Pleistocene. As one of the few MSA faunal assemblages from East Africa subject to detailed analysis, it provides rare insight into the foraging behavior of the early modern humans in this region. The MSA fauna include taxa that were not historically present in the area, with the occurrence of reduncines and alcelaphines indicating widespread grasslands and proximity to a perennial source of water. The faunal analysis examined several lines of evidence, including breakage patterns, surface modification, and skeletal-element representation. By incorporating comparisons with multiple actualistic data sets, the analysis of the assemblage demonstrates that, while the influence of carnivores and other biotic agents was evident, the faunal remains were accumulated primarily by hominid activity. The skeletal-element representation at Porc-Epic includes an abundance of high utility bones, in contrast to the predominance of "head-and-foot" elements documented at other MSA and Middle Paleolithic (MP) sites. The MSA occupants of Porc-Epic effectively exploited a wide range of prey with more emphasis on small- and medium-sized mammals. 相似文献
159.
Quantitative ethnobotany of two east Timorese cultures 总被引:1,自引:0,他引:1
Sean Collins Xisto Martins Andrew Mitchell Awegechew Teshome John Thor Arnason 《Economic botany》2006,60(4):347-361
This is the first time aspects of the ethnobotany of East Timor have been reported. The medicinal plant traditions of two
distinct East Timorese cultures, the Laklei and Idate, were studied and compared using quantitative ethnobotanical methods.
A total of 86 medicinal plant species were identified. The medicinal plant traditions of the Laklei and Idate cultures were
compared using Trotter and Logan’s (1986) quantitative “informant agreement ratio.” On average, informant consensus was greater
in Laklei, suggesting a medicinal plant tradition that is more defined than in Idate, where informants are more likely to
use the same medicinal plants when treating the same usage categories. Furthermore, only 11 of the 86 medicinal plant species
documented were used by both cultures, of which only six had similar mentions. These findings have important implications
for the understanding of ethnobotany as they demonstrate how relatively closely situated cultural groups can have significantly
different traditional knowledge systems. 相似文献
160.
Impact of Microzooplankton and Copepods on the Growth of Phytoplankton in the Yellow Sea and East China Sea 总被引:2,自引:0,他引:2
Dilution and copepod addition incubations were conducted in the Yellow Sea (June) and the East China Sea (September) in 2003.
Microzooplankton grazing rates were in the range of 0.37–0.83 d−1 in most of the experiments (except at Station A3). Correspondingly, 31–50% of the chlorophyll a (Chl a) stock and 81–179% of the Chl a production was grazed by microzooplankton. At the end of 24 h copepod addition incubations, Chl a concentrations were higher in the copepod-added bottles than in the control bottles. The Chl a growth rate in the bottles showed good linear relationship with added copepod abundance. The presence of copepods could enhance
the Chl a growth at a rate (Z) of 0.03–0.25 (on average 0.0691) d−1 ind−1 l. This study, therefore parallels many others, which show that microzooplankton are the main grazers of primary production
in the sea, whereas copepods appear to have little direct role in controlling phytoplankton. 相似文献