东方白鹳幼鸟渤海湾越冬群体的迁徙策略

东方白鹳(Ciconia boyciana)主要在俄罗斯远东和中国东北繁殖, 在中国主要有两个越冬群体(长江越冬群体, 迁徙距离约2,600 km; 渤海湾越冬群体, 迁徙距离约1,500 km)。本文基于2016-2018年的卫星追踪数据(N = 14), 分析了渤海湾越冬群体幼鸟春季和秋季的迁徙策略和利用风的方式, 总结了850 mb压力下风速和风向对日迁徙飞行速度的影响。该群体春秋两季迁徙距离相似, 但春季的顺风条件(2.2 ± 6.3 m/s)显著优于秋季的逆风条件(-2.4 ± 4.1 m/s, P < 0.05), 这使得春季迁徙飞行速度(280.4 ± 62.0 km/d)显著快于秋季(185.5 ± 72.0 km/d, P < 0.05), 春季迁徙飞行时间(5.9 ± 2.5 d)显著短于秋季(10.3 ± 6.5 d, P < 0.05); 同时, 春季停歇时间(5.4 ± 9.7 d)短于秋季(17.8 ± 18.2 d, P = 0.05)。基于以上原因, 东方白鹳春季迁徙持续时间(11.2 ± 8.7 d)显著短于秋季(28.0 ± 21.2 d, P < 0.05)。渤海湾越冬群体幼鸟迁徙时, 春季利用顺风更快到达度夏地, 秋季逆风迁徙, 迁徙飞行速度慢, 迁徙飞行时间和停歇时间长。因此, 东方白鹳迁徙时虽然主要利用上升热气流翱翔, 但顺风也是其成功迁徙的有利因素。     

云南大山包越冬黑颈鹤迁徙路线的卫星跟踪

2005年2月26日和3月1日在云南省昭通大山包黑颈鹤国家级自然保护区,分别为4只越冬黑颈鹤佩戴卫星信号发射器(PTTs),跟踪研究其迁徙路线和迁徙停歇地。2005年春季迁徙中,有2只跟踪黑颈鹤到达繁殖地,其中1只黑颈鹤在2005年11月和2006年3月分别完成从繁殖地返回越冬地和从越冬地再次到达繁殖地的迁徙过程。2只春季迁徙黑颈鹤的迁徙路线大致相同——沿着长江上游金沙江、大渡河一直向北到达黄河上游白河及黑河沿岸若尔盖湿地内。春季迁徙过程中,途中停歇3—4次,总迁徙距离是674—713km,迁徙全程所用时间3—4天。秋季迁徙全程所用时间8天。在4个PTTs工作期间,共确定有13个黑颈鹤迁徙停歇地,其中11个停歇地在河流滩地;其他2个停歇地在高山湖泊附近。总体上,黑颈鹤一般选择海拔在1900m以上湖泊、河流等湿地内,距离耕地较近且人、畜干扰较少的栖息地停歇。     

云南大山包越冬黑颈鹤迁徙路线的卫星跟踪

2005年2月26日和3月1日在云南省昭通大山包黑颈鹤国家级自然保护区，分别为4只越冬黑颈鹤佩戴卫星信号发射器（PTTs），跟踪研究其迁徙路线和迁徙停歇地。2005年春季迁徙中，有2只跟踪黑颈鹤到达繁殖地，其中1只黑颈鹤在2005年11月和2006年3月分别完成从繁殖地返回越冬地和从越冬地再次到达繁殖地的迁徙过程。2只春季迁徙黑颈鹤的迁徙路线大致相同——沿着长江上游金沙江、大渡河一直向北到达黄河上游白河及黑河沿岸若尔盖湿地内。春季迁徙过程中，途中停歇3—4次，总迁徙距离是674—713 km，迁徙全程所用时间3—4天。秋季迁徙全程所用时间8天。在4个PTTs工作期间，共确定有13个黑颈鹤迁徙停歇地，其中11个停歇地在河流滩地；其他2个停歇地在高山湖泊附近。总体上，黑颈鹤一般选择海拔在1 900 m以上湖泊、河流等湿地内，距离耕地较近且人、畜干扰较少的栖息地停歇。     

基于卫星跟踪大天鹅春季迁徙时间及其影响因素

候鸟春季迁徙时间与其能否顺利完成迁徙过程,以及对繁殖地的成功选择和繁殖成效密切相关,通过对大天鹅越冬地和停歇地的春季迁徙时间选择原因及其影响因素进行分析,有助于深入理解候鸟春季迁徙时间策略和栖息地保护状况。2015年2月和12月,在河南三门峡湿地捕捉了60只越冬大天鹅并佩戴卫星跟踪器,获取了详细的大天鹅在越冬地和停歇地的春季迁徙时间等信息,并进一步分析了春季迁徙时间与气候因子的相关性。结果表明,大天鹅主要在夜间22：00-0：00和0：00-1：59迁离越冬地。大天鹅迁离越冬地的日期与温度呈显著性正相关,迁离时多选择顺风且风速较小的天气。大天鹅迁离越冬地后主要是在夜间飞行,而迁离停歇地后主要是在日间飞行。越冬地的温度越高,越有利于植物的生长,大天鹅可以快速地积累能量,提前开始春季迁徙。野外调查表明,内蒙古黄河中上游作为迁徙的重要停歇地,春季两岸捕鱼、农耕和放牧等为活动较多,因此大天鹅多选择在夜间觅食补充能量,在日间迁离。最后,针对黄河流域大天鹅栖息地的保护现状,提出了禁止经济开发项目、建立保护区和开展宣传教育等保护建议。     

俄罗斯远东地区勺嘴鹬繁殖地夏季水鸟调查

俄罗斯远东地区是全球鸟类重要的繁殖地之一,特别是楚科奇半岛的阿纳德尔地区是全球极危鸟种勺嘴鹬(Calidris pygmeus)已知的重要繁殖地。为了履行中俄候鸟及其栖息地保护双边协定,掌握俄罗斯远东的阿纳德尔地区夏季水鸟的资源状况,2017年6月25日至7月20日,中俄双方对阿纳德尔南部地区进行了夏季水鸟资源调查。调查区域主要包括阿纳德尔、从阿纳德尔至白令戈夫斯基的海域、白令戈夫斯基、梅内皮尔吉诺周边苔原区域以及附近海域四个部分。共记录35种水鸟,隶属于6目10科,其中14种有繁殖活动。分析中俄环志回收数据表明,在我国长江流域和东部沿海地区越冬的雁鸭类和鸻鹬类水鸟,夏季迁徙到俄罗斯的哈巴罗夫斯克、萨哈林岛、勘察加半岛、雅库特、楚科奇等远东地区繁殖。此外,勺嘴鹬的主要繁殖繁殖地梅内皮尔吉诺周边苔原地区存在着巢址被洪水淹没、卵和雏鸟遭天敌捕食等风险;在勺嘴鹬迁徙路线上的重要迁徙停歇地和越冬地的退化、环境污染和人为活动是导致勺嘴鹬种群数量下降的重要因素。研究结果表明,需要进一步加强中俄双方勺嘴鹬保护的合作与交流,共同保护鸟类的栖息地。     

豆雁在中国的春季迁徙路线及迁徙停歇地

掌握禽流感病毒携带者豆雁(Anser fabalis)的迁徙路线对于全面理解候鸟在禽流感疫情传播与扩散中的作用具有重要意义。2013年3月至4月在江西省鄱阳湖南矶山保护区,利用卫星跟踪法对3只豆雁个体的迁徙路线进行研究,仅有1只个体成功传输数据。数据经Google Earth和Excel软件处理后,结果显示:该只豆雁由江西鄱阳湖出发,途经安徽、江苏、山东、天津等省市到达河北秦皇岛,5月被发现死于山海关,迁徙总距离约1 500 km,有5个停歇地;两相邻停歇地之间最短距离为20 km,最长为700 km;停留时间最短为1 d,最长为14 d;约68%的停歇位点地物类型为农田;飞行高度平均值为15 m,最大值为407 m。     

滦河上游——白枕鹤西部种群的重要停歇地

白枕鹤(Grus vipio)为国家II级重点保护野生动物, 被IUCN列为易危(VU)物种。白枕鹤西部种群繁殖于中蒙俄交界处的达乌尔地区, 数量呈下降趋势。我们于2017-2018年在蒙古国东部给白枕鹤西部种群的50只个体佩戴了GPS-GSM跟踪设备。截至2019年5月, 获得春季和秋季迁徙路径各48条。分析结果显示: 春季91.67%和秋季72.91%的跟踪个体在滦河上游(河北省沽源-内蒙古正蓝旗-多伦区域)停歇, 春季停留时间36.16 ± 15.00天、秋季20.26 ± 11.08天, 分别占春季和秋季迁徙时间的75%和67%, 确定了这一区域是西部种群迁徙途中最重要的停歇地。迁徙路线栖息地选择模型结果显示, 白枕鹤常在距离湖泊较近(< 210 km)、海拔1,200-1,500 m, 且坡度小(< 1°)的区域停歇。而滦河上游和整条迁徙路线停歇位点比较的模型结果显示, 滦河上游停歇地的海拔1,200-1,500 m与整条迁徙路线栖息地选择模型的结果一致; 此外这个区域离河流更近(< 70 km), 不仅有湿地和水体的栖息环境, 还有草地和农田可供觅食和栖息。保护空缺分析发现滦河上游现有四处保护地, 但在保护地内的迁徙停歇点不超过总位点的1.63%。综上, 我们建议将滦河上游整体纳入保护地体系进行管理, 为这一受胁物种及其栖息地管理和保护提供可靠保障。     

渤海湾地区红腹滨鹬迁徙动态的初步研究

红腹滨鹬(Calidris canutus)繁殖于环北极地区,属长距离迁徙鸟类,我国黄渤海地区是其在东亚-澳大利西亚迁徙路线上重要的停歇地。2003~2004年,通过对渤海湾北部双龙河口(东经118°21′,北纬37°2′)及其附近地区红腹滨鹬的种群调查,发现其迁徙高峰期出现在4月底到6月初,峰值为2004年5月15日的3 814只;2004年北迁时期,记录到佩戴有澳大利亚和新西兰脚旗的红腹滨鹬17只次,证实在澳大利亚西北部、东南部以及新西兰等3个地区越冬的2个红腹滨鹬亚种都在北迁时使用渤海湾作为其停歇地。     

基于卫星跟踪的洞庭湖越冬小天鹅迁徙路线研究

掌握洞庭湖越冬小天鹅Cygnus columbianus的迁徙行为和规律,明确迁徙路线和停歇地,是小天鹅栖息地恢复研究及保护的基础。2014—2017年,在湖南东洞庭湖国家级自然保护区对18只小天鹅进行卫星跟踪,收集了38 882条定位数据。本研究确定了小天鹅西线、中线和东线3条迁徙路线,其中,新发现的西线沿我国湖北、河南、山西、陕西、内蒙古,以及蒙古国、哈萨克斯坦,抵达俄罗斯亚马尔-涅涅茨自治区北部靠近喀拉海的北极苔原。西线春季迁徙距离为6 715 km,平均迁徙速度为21.52 km·h~(-1),秋季迁徙距离为7 467 km,平均迁徙速度为32.75 km·h~(-1)。中线春季迁徙距离为2 083 km,平均迁徙速度为28.93 km·h~(-1)。东线春季迁徙距离为5 965~6 351 km,平均迁徙速度为(28.71±0.95)km·h~(-1),秋季迁徙距离为5 101~5 331 km,平均迁徙速度为(29.15±3.65)km·h~(-1)。小天鹅春季迁徙进程慢于秋季,迁徙途中的最大飞行速度达133.3 km·h~(-1)。内蒙古自治区的黄河湿地和大兴安岭两侧河谷湿地是迁徙途中的重要中转站,小天鹅在此停歇15 d以上。本研究有助于了解小天鹅对栖息环境的偏好及迁徙路线选择策略,为禽流感等疾病传播和防控提供科学依据。     

崇明东滩鸻鹬类迁徙路线的环志分析

崇明东滩为东亚-澳大利西亚鸻鹬类迁徙路线上的重要迁徙停歇地.本文通过分析崇明东滩回收的异地环志鸻鹬类记录及异地回收的崇明东滩环志的鸻鹬类记录,研究崇明东滩鸻鹬类的迁徙路线.1979～2008年间,崇明东滩共回收到来自澳大利亚西北部、澳大利亚维多利亚、美国阿拉斯加及新西兰北岛等17个国家与地区环志的鸻鹬类265只,包括大滨鹬(Calidris tenuirostris)、斑尾塍鹬(Limosa lapponica)、红腹滨鹬(C.canutus)等16种鸟类,其中春季北迁期间的记录占总数的93%;2003～2008年间,澳大利亚西北部、新西兰南岛、中国大陆及新西兰北岛等10个国家与地区回收到崇明东滩环志的大滨鹬、斑尾塍鹬、红腹滨鹬等12种鸟类,共计164只.在所有与崇明东滩鸻鹬类存在迁徙连接的20个国家和地区中,澳大利亚西北部的回收记录占全部回收记录的55%.根据斑尾塍鹬和红腹滨鹬不同亚种的越冬地分布,崇明东滩回收的斑尾塍鹬有L.l.menzbieri与L.l.baueri两个亚种,红腹滨鹬有C.a.piersmai和C.a.rogersi两个亚种.     

Ageing index evolution in the Spanish population

Official statistics allow an analysis of the ageing index changes in the Spanish population from 1930 to 1975. During this period the ageing index values doubled from 19.11 to 38.60, the maximum increase having occurred between 1950 and 1960. Both birth and death rates lowered during the 45 years studid; however, the death rate decreased twice as fast. The natural increase rise was thus mainly due to a lower death rate. These data can explain a part of the ageing index transformation. By province, the ageing index range increased three-fold from 1930 to 1975. Some provinces showed an elevated index and others a reduced one. After 1960, extensive areas of inland Spain showed an older age structure because of emigration to industrialized towns.     

骨髓间充质干细胞在大鼠体内的迁移研究

目的:将体外预先标记的骨髓间充质干细胞(mesenchymalstemcells,MSCs)移植到大鼠脑内观察细胞的存活和转归,从在体(invivo)角度阐明MSCs在中枢神经系统疾病细胞治疗中的潜在应用前景。首先用DiI在体外标记MSCs。将标记后的MSCs分别移植到大鼠纹状体和侧脑室,在移植后2w和4w灌杀动物,进行脑组织及脊髓的冰冻切片,在荧光显微镜下观察细胞的存活与转归。结果:移植到纹状体的MSCs可沿针道向周围实质迁移,迁移的最远距离可达0.2mm。并且,在大脑皮层及其他脑实质的血管壁、血管中以及血管周围还可见到标记细胞;而移植到侧脑室的MSCs则主要沿脑室系统迁移,细胞主要分布在移植侧侧脑室,对侧脑室与第四脑室也有分布,也有少量细胞沿侧脑室向周围实质迁移,迁移的最远距离为0.23mm。还可见到沿胼胝体向对侧脑室迁移的细胞流,甚至有个别细胞迁移至脊髓腰段。所有动物在细胞移植后4周均未发现肿瘤形成。结论:MSCs脑内移植后可以在中枢神经系统内存活并迁移,无致瘤性。结果提示骨髓间充质细胞是很多疾病细胞与基因治疗的有力工具。     

The effects of large and small-scale random events on the synchrony of metapopulation dynamics: a theoretical analysis

We present an analysis of the conditions under which migration and global random factors may determine large scale synchrony in the dynamics of spatially structured populations. We derive an analytic approximation which describes how the desynchronizing influence of local environmental stochasticity combines with the synchronizing influences of larger scale environmental stochastic variation and migration to determine population cross correlation coefficients. Despite the simplifications made by this analysis, computer simulations show that the behaviour of more complicated models is well described by our approximation over considerable regions of parameter space. We conclude that population synchrony is largely determined by the coefficients of variation (CVs) of the local and larger scale stochastic processes, and that migration alone is only likely to maintain population synchrony when the CV of the local stochastic process is very small.     

An Inhomogeneous Markov Model to Fit the Migration Process

In this paper we study the migration process considering an inhomogeneous Markov model. This is a certain condition to investigate age-dependent population distributions, where the transition probabilities are not constant. We consider also a death process for a population alive in a region at age t and, as a result of this, combined transition probabilities between the states of the concerning Markov chain. The model has non-stationary distribution for t →∞, because the condition of ergodicity does not hold.     

Breast cancer cells attract the migration of adipose tissue-derived stem cells via the PDGF-BB/PDGFR-β signaling pathway

The origin of vascular cells in tumors is unknown, but it is believed that tumors use cells from the host to build new vessels. To determine whether adipose tissue stem cells (ASCs) could be attracted by cancer cells, we performed migration assays in which ASCs were seeded on a transwell migration system top chamber and tumor-conditioned medium was placed in the bottom chamber. Our data showed that a significant number of ASCs migrated toward the tumor-conditioned medium (p < 0.0001), and migration of human ASCs significantly (p < 0.0001) increased in response to increased concentrations of recombinant PDGF-BB. In addition, neutralizing antibodies to PDGF receptor (PDGFR)-β decreased migration of ASCs toward a breast cancer-conditioned medium to the level of serum-free control. These data suggest that tumor cell-derived PDGF-BB is an important factor in governing the microenvironment interaction between tumor cells and local tissue-resident stem cells.     

Corridors for migration between large subdivided populations, and the structured coalescent

We study the ancestral genetic process for samples from two large, subdivided populations that are connected by migration to, from, and within a small set of subpopulations, or demes. We consider convergence to an ancestral limit process as the numbers of demes in the two large, subdivided populations tend to infinity. We show that the ancestral limit process for a sample includes a recent instantaneous adjustment to the sample size and structure followed by a more ancient process that is identical to the usual structured coalescent, but with different scaled parameters. This justifies the application of a modified structured coalescent to some hierarchically structured populations.     

First record of the bluespotted cornetfish from the Mediterranean Sea

Three specimens of the Indo-Pacific Bluespotted cornetfish Fistularia commersonii are recorded for the first time from the Mediterranean. The presence of this species in the Mediterranean is due to migration from the Red Sea via the Suez Canal.     

Characteristics of hamadryas-like male baboons living in anubis baboon troops in the Awash hybrid zone, Ethiopia.

In the twenty-two years since the Awash baboon hybrid zone was first described, about 25-30 hamadryas or hamadryas-like hybrid males have taken up residence in anubis baboon groups. Most enter as mature adults, though some may immigrate as juvenile followers. Long-term tracking of known immigrants indicates that they may reside for four years or more in their adopted troop, during which time they establish a series of comparatively short-term harems, and probably sire hybrid offspring. "Abductions" of anubis females to hamadryas troops, as postulated by early observers, were not seen, though their occurrence cannot be ruled out. Younger, more recent immigrants tend to be "purer" hamadryas in phenotype, perhaps reflecting a more distant origin, or a change in the composition of neighboring hamadryas populations. Coexisting hamadryas and anubis show no signs of reproductive isolation by behavioral barriers, and evidently belong to a single "recognition species."     

Marital mobility in populations of the High Aran Valley

The analysis of 2.623 marriage certificates in the towns in the High Aran Valley shows marriage mobility between the years 1650 and 1990 and indicates the level of population's endogamy. The results from the data collected in the town of Arties are presented as an example. The distribution of the places of origin of spouses and a factor analysis show a remarkable geographical endogamy until 1940. The results from marriage mobility are confirmed by data from blood polymorphism studies, matrimonial dispensations and surnames.