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清初“迁海”对广东社会经济的影响 被引量:12
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作者 李龙潜 李东珠 《暨南学报(哲学社会科学版)》 CSSCI 1999年第4期47-57,共11页
清初“迁海”对广东社会经济的影响:一是严重地破坏了农业生产力,二是破坏了手工业生产,主要是盐业和制香业等,三是阻碍了沿海商品经济的发展,四是造成地方财政困难,加重了人民的赋役负担。此外,对文化教育的影响也很大。总之,... 清初“迁海”对广东社会经济的影响:一是严重地破坏了农业生产力,二是破坏了手工业生产,主要是盐业和制香业等,三是阻碍了沿海商品经济的发展,四是造成地方财政困难,加重了人民的赋役负担。此外,对文化教育的影响也很大。总之,“迁海”是清政府的弊政.推迟了广东社会经济的发展几十年。 展开更多
关键词 “迁海” 农业生产力 熬盐 地丁
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清初广东“迁海”的经过及其对社会经济的影响──清初广东“迁海”考实 被引量:7
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作者 李东珠 《中国社会经济史研究》 CSSCI 北大核心 1995年第1期94-101,共8页
清初广东“迁海”的经过及其对社会经济的影响──清初广东“迁海”考实李东珠1“迁海”的目的和范围清初统一战争未结束,各地尚处于政治不稳定状态,特别是退守台湾后待机反攻的郑成功等,企图联合东南沿海的明朝遗民共同抗清,而沿... 清初广东“迁海”的经过及其对社会经济的影响──清初广东“迁海”考实李东珠1“迁海”的目的和范围清初统一战争未结束,各地尚处于政治不稳定状态,特别是退守台湾后待机反攻的郑成功等,企图联合东南沿海的明朝遗民共同抗清,而沿海居民在物质上,精神上都给义师极大... 展开更多
关键词 “迁海” 社会经济 清政府 广东通志 外距 康县 香山 博物馆 广东沿 南岛
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施琅统一台湾与清初的开海贸易
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作者 刘凤云 《中共福建省委党校学报》 北大核心 2004年第3期53-57,共5页
关键词 施琅 台湾省 祖国统一 清朝初期 上贸易 “禁令” “迁令” “开贸易”
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试论清代前期两广总督的选任与治绩 被引量:1
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作者 关汉华 《广东社会科学》 CSSCI 1997年第6期83-88,共6页
试论清代前期两广总督的选任与治绩关汉华一两广设置总督,始于明代景泰三年(1452年),当时两广“浔、梧瑶乱,……特遣一大臣督军务,乃以命(王)翱。两广有总督自翱始。”①。然这一建制在当时尚不稳定,到成化元年(1465... 试论清代前期两广总督的选任与治绩关汉华一两广设置总督,始于明代景泰三年(1452年),当时两广“浔、梧瑶乱,……特遣一大臣督军务,乃以命(王)翱。两广有总督自翱始。”①。然这一建制在当时尚不稳定,到成化元年(1465年),为平“瑶乱”再派韩雍出任两广... 展开更多
关键词 《清史稿》 清代前期 《清史列传》 总督 经世文编 广东 进士出身 “迁海” 陈宏谋
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Population Dynamics and Breeding Space Niche of Four Heron Species in Tanghai Wetlands 被引量:5
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作者 李巨勇 李素萍 +2 位作者 孙砚峰 吴跃峰 武明录 《Zoological Research》 CAS CSCD 北大核心 2006年第4期351-356,共6页
The population dynamics and breeding behaviors of Black-crowned Night Herons ( Nycticorax nycticorax ), Egrets (Egtetta garzetta), Chinese Pond Herons (Ardeola bacchus) and Great Egrets (Casmerodius albus) wer... The population dynamics and breeding behaviors of Black-crowned Night Herons ( Nycticorax nycticorax ), Egrets (Egtetta garzetta), Chinese Pond Herons (Ardeola bacchus) and Great Egrets (Casmerodius albus) were observed in Tanghai Wetlands, Hebei Province from August 2004 to July 2005. Further, we studied the relationship of nest space distribution and directly calculated the nest density of vertical and horizontal levels, the niche overlapping index and the niche breadth. The results showed that there were two breeding areas, named Area Ⅰ and Area Ⅱ . The maximum population occurred in the period from April to September and was approximately 5800 individuals. Area Ⅰ was occupied earlier than Area Ⅱ by approximately half a month. In the breeding period, Black-crowned Night Herons were dominant in numbers and most occupied the upper nests of the core areas. Great Egrets also took the upper nests but they have the smallest population. Most Egrets took the middle nests of the edges of the area. Chinese Pond Herons, with a smaller population than the Egret, mostly nested in the edges, but some of them also took the lower nests of the core area. On the whole, the vertical niche of Egrets is the widest, the horizontal niche of Black-crowned Night Herons is the widest and the niche breadth of Chinese Pond Herons is the largest. The nest distribution pattern is the most similar between Chinese Pond Herons and Black-crowned Night Herons, and the niche overlapping index of Chinese Pond Herons and Egrets is the largest. Black-crowned Night Herons and Great Egrets control Egrets and Chinese Pond Herons in competition. Rich food and the optimal ecological environments lead to plenty of herons in the wetlands. In addition, it is a distinguishing feature of the four species that nests are built in poplar trees over 22 m tall. 展开更多
关键词 Tanghai Wetlands Breeding herons Population dynamics Nest areas Spatial niche
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EphA3 functions are regulated by collaborating phosphotyrosine residues
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作者 Guanfang Shi Gang Yue Renping Zhou 《Cell Research》 SCIE CAS CSCD 2010年第11期1263-1275,共13页
Ephrin ligands interact with Eph receptors to regulate a wide variety of biological and pathological processes. Recent studies have identified several downstream pathways that mediate the functions of these receptors.... Ephrin ligands interact with Eph receptors to regulate a wide variety of biological and pathological processes. Recent studies have identified several downstream pathways that mediate the functions of these receptors. Activation of the receptors by ephrin binding results in the phosphorylation of the receptor tyrosine residues. These phospho- rylated residues serve as docking sites for many of the downstream signaling pathways. However, the relative contributions of different phosphotyrosine residues remain undefined. In the present study, we mutated each individual tyrosine residues in the cytoplasmic domain of EphA3 receptor and studied the effects using cell migration, process retraction, and growth cone collapse assays. Stimulation of the EphA3 receptor with ephrin-A5 inhibits 293A cell mi- gration, reduces NG108-15 cell neurite outgrowth, and induces growth cone collapse in hippocampal neurons. Muta- tion of either Y602 or Y779 alone partially decreases EphA3-induced responses. Full abrogation can only be achieved with mutations of both Y602 and Y779. These observations suggest a collaborative model of different downstream pathways. 展开更多
关键词 tyrosine phosphorylation signal transduction cell migration growth cone collapse
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浅说“迁海令”对深圳龙岗地区的影响
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作者 纪小明 尚明权 秦加生 《广东史志.视窗》 2008年第1期48-51,共4页
清顺治末到康熙初年的“迁海令”,是清王朝一项重要的治国方略。对此,专家学者的研究和论述不少。笔者想就“迁海令”,对深圳龙岗中东部地区带来的影响,谈一点粗浅的看法。
关键词 龙岗 深圳 中东部地区 治国方略 专家学者 清王朝 康熙 “迁令”
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Evaluation of removal of the size effect using data scaling and elliptic Fourier descriptors in otolith shape analysis, exemplified by the discrimination of two yellow croaker stocks along the Chinese coast 被引量:1
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作者 赵博 刘金虎 +2 位作者 宋骏杰 曹亮 窦硕增 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第6期1482-1492,共11页
Removal of the length ef fect in otolith shape analysis for stock identification using length scaling is an important issue; however, few studies have attempted to investigate the ef fectiveness or weakness of this me... Removal of the length ef fect in otolith shape analysis for stock identification using length scaling is an important issue; however, few studies have attempted to investigate the ef fectiveness or weakness of this methodology in application. The aim of this study was to evaluate whether commonly used size scaling methods and normalized elliptic Fourier descriptors(NEFDs) could ef fectively remove the size ef fect of fish in stock discrimination. To achieve this goal, length groups from two known geographical stocks of yellow croaker, L arimichthys polyactis, along the Chinese coast(five groups from the Changjiang River estuary of the East China Sea and three groups from the Bohai Sea) were subjected to otolith shape analysis. The results indicated that the variation of otolith shape caused by intra-stock fish length might exceed that due to inter-stock geographical separation, even when otolith shape variables are standardized with length scaling methods. This variation could easily result in misleading stock discrimination through otolith shape analysis. Therefore, conclusions about fish stock structure should be carefully drawn from otolith shape analysis because the observed discrimination may primarily be due to length ef fects, rather than dif ferences among stocks. The application of multiple methods, such as otoliths shape analysis combined with elemental fingering, tagging or genetic analysis, is recommended for sock identification. 展开更多
关键词 otolith shape analysis data scaling for fish length stock discrimination removal of length effect
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Comparison of the water-crossing behavior of Western Marsh Harriers(Circus aeruginosus) and European Honey Buzzards(Pernis apivorus) during autumn migration
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作者 Michele PANUCCIO Nicolantonio AGOSTINI 《Chinese Birds》 2010年第1期30-35,共6页
We investigated the water-crossing behavior of Western Marsh Harriers(Circus aeruginosus),mostly adults,and European Honey Buzzards(Pernis apivorus),mostly juveniles,in relation to wind conditions,time of the day,floc... We investigated the water-crossing behavior of Western Marsh Harriers(Circus aeruginosus),mostly adults,and European Honey Buzzards(Pernis apivorus),mostly juveniles,in relation to wind conditions,time of the day,flocking and age classes,at a watchsite in central Italy during the autumn migration en route to Africa.Although European Honey Buzzards are less suited than Western Marsh Harriers to undertake long sea crossings,they were more inclined to leave the coast when migrating in flocks.Few birds of both species chose to fly along the coast.Western Marsh Harriers,such as European Honey Buzzards migrating alone,undertook the water crossing rather than stopping migration(birds roosting at the site or flying back inland) during the absence of wind and vice versa during head winds.Conversely,European Honey Buzzards migrating in flocks were not affected in their decision(crossing or stopping migration) by wind direction.Both species undertook the water crossing rather than stopping migration during mornings and vice versa during afternoons.Finally,in both species,adults and juveniles showed the same behavior in front of a water barrier.This result was expected in the case of the Western Marsh Harrier but not from the European Honey Buzzard since,in this species,the water-crossing tendency is age dependent with adults avoiding sea crossings.Our study confirms that flocking significantly affects the water-crossing behavior of European Honey Buzzards during migration.Moreover,in this species,inexperience of juveniles and presumably younger adults,about the high energetic costs of long powered flight and about the existence of shorter routes over water,might explain the strong water-crossing tendency shown by migrants independently from their age. 展开更多
关键词 Western Marsh Harrier European Honey Buzzard migration water-crossing behavior flocking wind age classes Mediterranean Sea
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Oil source and migration process in oblique transfer zone of Fushan Sag,northern South China Sea 被引量:1
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作者 王观宏 王华 +3 位作者 甘华军 时阳 赵迎冬 陈善斌 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第3期654-668,共15页
The oblique transfer zone in the Fushan Sag, a syndepositional dome sandwiched between the Bailian and Huangtong sub-sags, has been the most important exploration target. The major oil observation occurs in the E_2l_1... The oblique transfer zone in the Fushan Sag, a syndepositional dome sandwiched between the Bailian and Huangtong sub-sags, has been the most important exploration target. The major oil observation occurs in the E_2l_1^(L+M) and the E_2l_3~U. 46 oil and rock samples reveal that the oil in the transfer zone is mostly contributed by the Bailian sub-sag, though the source rock conditions, hydrocarbon generation and expulsion histories of the Bailian and Huangtong sub-sags are similar. The E_2l_3~U oil, characterized by high maturity, Pr/Ph ratio and oleanane/C_(30)-hopane ratio, shows a close genetic affinity with the E_2l_3~b source rocks, while the E_2l_1^(L+M) oil, characterized by lower maturity, Pr/Ph ratio and oleanane/C_(30)-hopane ratio, is suggested to be derived from the E_2l_(1+2)~b source rocks. The homogenization temperatures of aqueous fluid inclusions, taking the burial history of the reservoirs into account, reflect that the oil charge mainly occurred from mid-Miocene to Pliocene in the oblique transfer zone. The oil transporting passages include connected sand bodies, unconformities and faults in the Fushan Sag. Of these, the faults are the most complicated and significant. The faults differ sharply in the west area, the east area and the oblique transfer zone, resulting in different influence on the oil migration and accumulation. During the main hydrocarbon charge stage, the faults in the west area are characterized by bad vertical sealing and spatially dense distribution. As a result, the oil generated by the Huangtong source rocks is mostly lost along the faults during the vertical migration in the west area. This can be the mechanism proposed to explain the little contribution of the Huangtong source rocks to the oil in the oblique transfer zone. Eventually, an oil migration and accumulation model is built in the oblique transfer zone, which may provide theoretical and practical guides for the oil exploration. 展开更多
关键词 oblique transfer zone oil-source correlation oil loss oil migration and accumulation model Fushan Sag
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Phase Evolution of Holocene Paleoenvironmental Changes in the Southern Yellow Sea: Benthic Foraminiferal Evidence from Core CO2 被引量:8
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作者 FANG Li XIANG Rong +3 位作者 ZHAO Meixun ZHOU Liping LIU Jianguo ZHANG Lanlan 《Journal of Ocean University of China》 SCIE CAS 2013年第4期629-638,共10页
Assemblages of benthic foraminifera in a sediment core(C02)near the western margin of the southern Yellow Sea Mud were studied to decipher the phase evolution of Holocene paleoenvironmental changes associated with the... Assemblages of benthic foraminifera in a sediment core(C02)near the western margin of the southern Yellow Sea Mud were studied to decipher the phase evolution of Holocene paleoenvironmental changes associated with the Holocene marine transgression.It appears that during the early Holocene(11.2 10.1 kyr BP),the faunal was dominated by low salinity and shallow water species Cribrononion subincertum,Buccella frigida and Ammonia beccarii,reflecting a near coast depositional environment.A rapid increase of the relative abundance of Ammonia compressiuscula between 10.1 9.3 kyr BP indicates that the sea level rose rapidly during that time period.From 9.3 7.7 kyr BP,the benthic foraminiferal assemblage was dominated by high percentage of A.compressiscula,suggesting that the sea level was relatively stable.An obvious transition of benthic foraminifera,from the A.compressiuscula-dominated assemblage to an Ammonia ketienziensis-dominated assemblage,occurred between 7.7 6.2 kyr BP,possibly corresponding to a second sea level rapid rise period in the Yellow Sea during the Holocene.This transition may correspond to the gradually strengthened Yellow Sea warm current(YSWC)and finally is established the modern-type circulation in the Yellow Sea.It may also mark the formation of the Yellow Sea cold bottom water(YSCBW)during that period.Since then,the benthic foraminiferal assemblage based on core C02 was dominated by typical YSCBW species,A.ketienziensis,Astrononion italicum and Hanzawaia nipponica,at 6.2 4 kyr BP.A non-deposition period occurred since 4 kyr BP,which possibly related to the hydrology changes caused by the East Asia monsoon.The two obvious benthic foraminiferal transitions recorded in core C02 during the early and middle Holocene provide evidence that the Yellow Sea has undergone a two-phase rapid sea level rise during the Holocene marine transgression. 展开更多
关键词 benthic foraminifera HOLOCENE southern Yellow Sea PALEOENVIRONMENT marine transgression
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Seasonal variation in abundance, diel vertical migration and body size of pelagic tunicate Salpa fusiformis in the Southern Yellow Sea 被引量:4
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作者 LIU Yongqin SUN Song ZHANG Guangtao 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第1期92-104,共13页
Mass occurrence of Salpafusiformis June 2007. In order to investigate its population was observed in the Southern Yellow Sea in May and recruitment and environmental adaptation, temporal variation of abundance, diel v... Mass occurrence of Salpafusiformis June 2007. In order to investigate its population was observed in the Southern Yellow Sea in May and recruitment and environmental adaptation, temporal variation of abundance, diel vertical migration (DVM) and length frequency distribution of both aggregate and solitary forms were studied with samples collected from eight months during September 2006 to August 2007. S. fusiformis presented in six months other than September and October 2006, and average abundance of aggregate and solitary forms peaked in June and May, respectively. In December, aggregate forms were absent in the bottom layer and performed irregular DVM from surface to 50 m depth, while solitary forms was too scarce to perform diel vertical distribution analysis. Both aggregate and solitary forms presented reverse DVM in May and June. They migrated upwards during daytime and concentrated in surface layer at sunset. The bimodal distribution of aggregate forms was found in April and the average size was largest in this month. In other months, the smaller aggregate forms (1-5 ram) dominated in populations except for May, when the modal size ranged from 2 to 8 mm. The average size of solitary forms was largest in December, followed by April. The skewed nomal distribution of solitary forms was found in May and June, with the modal size of 2-7 mm and 5-13 ram, respectively. 展开更多
关键词 Salpafusiformis SWARM diel vertical migration length frequency Southern Yellow Sea
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Migration Effects to the Marine Ecosystem of Barangay Concepcion
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作者 Marjorie Astorias-Espanola 《Journal of Life Sciences》 2017年第7期341-345,共5页
Concepcion is one of the small island barangay in the municipality of Agutaya. It has a total landmass of 132.297 hectares. It is located within Quinluban group of islands. This place has the variety of natural resour... Concepcion is one of the small island barangay in the municipality of Agutaya. It has a total landmass of 132.297 hectares. It is located within Quinluban group of islands. This place has the variety of natural resources like seaweeds, turtles, fish and other seafood. The prominent product in this island is "agar-agar" also known as Tambalang (local name) and other marine resources. This study determined the effects of migration to the marine ecosystem of the place. Survey method and interview schedule were used during the data gathering. Results show that most migrants came to plant seaweeds or agar-agar. Poverty motivated them to migrate in the area. The abundance of marine resources also is one of the factors for migration for these people. They experienced poverty and economic crisis in their previous place which motivated them to explore and migrate to support their basic needs. 展开更多
关键词 ENVIRONMENT human migration descriptive survey method Cuyo PALAWAN Philippines
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Long-term ecological interactions between nutrient and phytoplankton community in the Changjiang estuary 被引量:9
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作者 江涛 俞志明 +2 位作者 宋秀贤 曹西华 袁涌铨 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第4期887-898,共12页
Both nitrate((NO_3)^-) and soluble reactive phosphate((PO_4)^(3-)) concentration in the freshwater end-member at the mouth of the Changjiang River have increased dramatically since the 1960s.Within the same period in ... Both nitrate((NO_3)^-) and soluble reactive phosphate((PO_4)^(3-)) concentration in the freshwater end-member at the mouth of the Changjiang River have increased dramatically since the 1960s.Within the same period in the sea area,with surface salinity>30,(NO_3)^-concentration has shown an obvious increase,(PO_4)^(3-) has not changed greatly and dissolved reactive silica((SiO_3)^(2-)) has deceased dramatically.An examination of the elemental ratio of(NO_3)^-to(PO_4)^(3-) at the mouth of the Changjiang River did not show a systematic trend from the 1960s to 2000s largely because both nutrients increased simultaneously.In comparison,the elemental ratio of dissolved inorganic nitrogen(DIN) to(PO_4)^(3-) in surface seawater,with salinity>22,has shown a clearly increasing trend.Furthermore,an overall historical change of the(SiO_3)^(2-):(PO_4)^(3-) ratio has undergone a reverse trend in this area.Based on the changes of(SiO_3)^(2-):(PO_4)^(3-) and DIN:(PO_4)^(3-) ratios,we can conclude that an overall historical change of(SiO_3)^(2-):DIN ratio has decreased in this area from the 1950-1960s to 2000s.The argument that phytoplankton productivity in the Changjiang estuary has been enhanced by increasing nutrient input from the riverine transport was supported by these results.A comparative study analyzing the shift of phytoplankton composition from the mid-1980s to 2000s was also made.The results indicated that the average yearly percentage of diatom species in the Changjiang estuary has decreased from 84.6% during 1985-1986 to 69.8% during 2004-2005.Furthermore,the average yearly percentage of diatom abundance in the Changjiang estuary decreased from 99.5% during to 75.5% over the same time period,while the abundance of dinoflagellates has increased dramatically,from 0.7% to 25.4%. 展开更多
关键词 EUTROPHICATION NUTRIENTS phytoplankton community Changjiang estuary
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Wuliangsuhai Wetlands: A Critical Habitat for Migratory Water Birds 被引量:2
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作者 张雅棉 贾亦飞 +4 位作者 焦盛武 曾晴 冯多多 郭玉民 雷光春 《Journal of Resources and Ecology》 CSCD 2012年第4期316-323,共8页
Wuliangsuhai wetland is one of the representative wetlands in arid-semiarid region. It is also a key breeding site as well as a stepping site for both East Asia-Australasia Flyway and Central Asia Flyway. From 2009 to... Wuliangsuhai wetland is one of the representative wetlands in arid-semiarid region. It is also a key breeding site as well as a stepping site for both East Asia-Australasia Flyway and Central Asia Flyway. From 2009 to 2012, surveys on migratory water birds and their habitat were carried out by using transects census and spot count methods. The surveys recorded more than 100 000 water birds, and 98 species were identified, which belong to 6 orders and 14 families. Among the 98 species, 55 are summer residents (breeding here) and 39 are travelers (only stay here shortly), which account for 56.12% and 39.80% of the total recorded bird species respectively. Further analysis on their migration pattern shows that spring migration is mainly from early March to mid May, which is shorter than autumn migration season (from early August to mid November). Most of the summer residents breed from early April to late May. High concentration of key protected species were observed from early April to early May and from early September to early November. The bird community structure is relatively stable in summer, but much more dynamic during the migration seasons (spring and autumn). Based on the study, recommendation to nominate Wuliangsuhai wetlands as Ramsar site, and flyway network site were put forward. Habitat management that address to the environmental determinants on bird distribution was also discussed. 展开更多
关键词 Wuliangsuhai water bird migration pattern FLYWAY wetland management
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Migration of multiples from the South China Sea 被引量:7
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作者 LIU YiKe ZHU WeiLin +2 位作者 MI LiJun ZHOU JiaXiong HAO Hu 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第3期482-490,共9页
The South China Sea where water depth is up to 5000 m is the most promising oil and gas exploration area in China in the future.The seismic data acquired in the South China Sea contain various types of multiples that ... The South China Sea where water depth is up to 5000 m is the most promising oil and gas exploration area in China in the future.The seismic data acquired in the South China Sea contain various types of multiples that need to be removed before imaging can be developed.However,compared with the conventional reflection migration,multiples carry more information of the underground structure that helps provide better subsurface imaging.This paper presents a method to modify the conventional reverse time migration so that multiple reflections can migrate to their correct locations in the subsurface.This approach replaces the numerical impulsive source with the recorded data including primaries and multiples on the surface,and replaces the recorded primary reflection data with multiples.In the reverse time migration process,multiples recorded on the surface are extrapolated backward in time to each depth level,while primaries and multiples recorded on the surface are extrapolated forward in time to the same depth levels.By matching the difference between the primary and multiple images using an objective function,this algorithm improves the primary resultant image.Synthetic tests on Sigsbee2 B show that the proposed method can obtain a greater range and better underground illumination.Images of deep water in the South China Sea are obtained using multiples and their matching with primaries.They demonstrate that multiples can make up for the reflection illumination and the migration of multiples is an important research direction in the future. 展开更多
关键词 the South China Sea reverse time migration of multiples seismic imaging
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Individual consistency and sex differences in migration strategies of Scopoli's shearwaters Calonectris diomedea despite year differences 被引量:1
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作者 Martina S. MULLER Bruno MASSA +1 位作者 Richard A. PHILLIPS Giacomo DELL 《Current Zoology》 SCIE CAS CSCD 2014年第5期631-641,共11页
Recently-developed capabilities for tracking the movements of individual birds over the course of a year or longer has provided increasing evidence for consistent individual differences in migration schedules and dest... Recently-developed capabilities for tracking the movements of individual birds over the course of a year or longer has provided increasing evidence for consistent individual differences in migration schedules and destinations. This raises questions about the relative importance of individual consistency versus flexibility in the evolution of migration strategies, and has implications for the ability of populations to respond to climatic change. Using geolocators, we tracked the migrations of Scopoli's shearwaters Calonectris diomedea breeding in Linosa (Italy) across three years, and analysed timing and spatial aspects of their movements. Birds showed remarkable variation in their main wintering destination along the western coast of Africa. We found significant individual consistency in the total distance traveled, time spent in transit, and time that individuals spent in the win- tering areas. We found extensive sex differences in scheduling, duration, distances and destinations of migratory journeys. We also found sex differences in the degree of individual consistency in aspects of migration behaviour. Despite strong evidence for individual consistency, which indicates that migration journeys from the same bird tended to be more similar than those of dif- ferent birds, there remained substantial intra-individual variation between years. Indeed, we also found clear annual differences in departure dates, return dates, wintering period, the total distance traveled and re^rn routes from wintering grounds back to the colony. These findings show that this population flexibly shifts migration schedules as well as routes between years in response to direct or indirect effects of heterogeneity in the environment, while maintaining consistent individual migration strategies [Current Zoology 60 (5): 631-641, 2014]. 展开更多
关键词 Avian migration GLS loggers REPEATABILITY Individual strategies
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Mineralogy of the otoliths of naked carp Gymnocypris przewalskii (Kessler) from Lake Qinghai and its Sr/Ca potential implications for migratory pattern 被引量:6
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作者 ZHOU Ling JIN ZhangDong LI FuChun 《Science China Earth Sciences》 SCIE EI CAS 2012年第6期983-990,共8页
Otoliths are biogenic carbonate minerals whose microstructure and microchemistry have been used for age determination, stock identification, life history and environmental tracing. Using X-ray diffraction (XRD) and ... Otoliths are biogenic carbonate minerals whose microstructure and microchemistry have been used for age determination, stock identification, life history and environmental tracing. Using X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy, we have determined the mineral types and crystalline characteristics of three pairs of otoliths from naked carp Gymnocypris przewalskii, the predominant fish in Lake Qinghai. The results indicate that the mineral of both lapillus and sagitta of the naked carp is aragonite, and that of asteriscus is vaterite. The aragonite of lapillus has prefect crystallization. Given the shape of lapillus and the sensitivity of its aragonite to water chemistry, lapillus was used to analyze temporal Sr/Ca ratios along the maximal growth axis by an electron probe microanalyzer (EPMA). Consistent variations of Sr/Ca ratios with a range of 1.0x10-3-5.0~10-3 on the long and short radii indicate that Sr/Ca ratios of lapillus potentially respond to the chemical compositions of the host waters during the period of the naked carp's growth and migration. Discontinuous (dark) zones of lapillus were formed during fall and winter when the naked carp grows slowly in Lake Qinghai, resulting in similar low Sr/Ca ratios to lake water, whereas incremental zones with higher St/Ca ratios respond to its migratory river waters during spring and summer. Various Sr/Ca ratios of incremental zones suggest that the migratory pattern of the naked carp may be much more flexible, rather than in a single river. Therefore, high-resolution otolith microchemistry of the naked carp can be used to trace its migratory behavior, which is of significance for determining its migratory pattern and life history of this precious species inhabiting the Tibetan Plateau. 展开更多
关键词 Lake Qinghai naked carp OTOLITH MIGRATION ARAGONITE Sr/Ca ratio environmental tracer
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