科创中国

Lesser kestrels Falco naumanni are migratory central-place foragers that breed in dynamic arable landscapes. After arriving from migration, kestrels have no knowledge of the distribution of crops, and consequently prey, around their colony. The energy demand of pairs increases as breeding season progresses, but at the same time prey abundance, and their knowledge on prey distribution, also increases. Wind can have a strong influence on flight cost and kestrels should try to reduce energy expendi- ture when possible. When prey abundance is low, kestrels have little knowledge of prey distribution, and pairs have no chicks, they could reduce foraging flight cost by leaving the colony with tailwinds. When prey is abundant, knowledge on prey distribu- tion has increased, and chick demand is high, kestrels should fly to the most favorable foraging patches. We analyzed foraging trips directions in a lesser kestrel colony along the breeding season and in relation to wind speed and direction. We recorded 664 foraging trips from 19 individuals using GPS-dataloggers. We found that outward flights direction changed from uniform to a concentrated distribution along the season, as prey abundance and individual experience increased. We also found a temporal trend in the angular difference between outward flights and wind directions, with low values early in the season and then increa- sing as expected, but again low values at the end, contrary to expectation. Results suggest changes in kestrels foraging strategy along the season in relation to wind. Kestrels depart more with tailwinds in exploratory flights early in the season, while there is a spurious coincidence in direction to preferred foraging patches and dominant wind direction at the end [Current Zoology 60 (5): 604-615, 2014].

主要阐述特殊地质即季节性冻土条件下接触网支柱基础的设计理念.针对东北地区季节性冻土这一特殊土壤特性,提出采用机械扩底桩基来抵抗季节性冻土冻胀上拔,其优点是有效地提高抗冻拔力及减少钻孔深度,尽可能减少支柱基础与路基内桩板结构干扰.机械钻孔扩底桩基是季节性冻土代表区域内高速铁路建设中接触网支柱基础设计可选的优化方案,也是支柱基础底部受到地基处理措施干扰及湿陷性黄土影响要求基础浅埋时的佳选.

目的 调查分析浙西山区老年高血压患者血压的季节变化特征.方法 431例未经治疗的老年高血压患者为观察组,584例健康老年人为对照组,采用校正的汞柱式血压计测量四季血压,比较分析.结果 老年高血压观察组夏季收缩压与冬季收缩压值分别为(141.8±18.3) mmHg、(146.6±19.6) mmHg(t=5.48,P<0.01);夏季舒张压与冬季舒张压值分别为(79.0±10.1)mmHg、(80.7±10.0)mmHg(t=3.60,P<0.01);夏季脉压与冬季脉压分别为(61.5±17.1) mmHg、(64.5±18.5)mmHg(t =3.99,P<0.01).观察组的冬季血压高于夏季.结论 浙西山区老年高血压患者的血压的季节波动幅度明显,冬季高于夏季.了解高血压季节波动规律,有助于对高血压患者的临床治疗与并发症的预防.

利用NCEP/NCAR日平均再分析资料及中国596个测站日降水资料,采用带通滤波、小波功率谱、合成分析、相关分析等方法对青藏高原夏季西风异常年500hPa纬向风季节内振荡特征及其与我国降水和大气环流的关系进行了分析,结果表明:青藏高原夏季500hPa纬向风季节内振荡以40~60d周期为主;该季节内振荡在高原西风异常年份表现出异常的传播特征;且高原西风增强年份,我国30°N~40°N范围内的低频降水与高原低频纬向风几乎为同位相,30°N以南地区的低频降水与高原低频纬向风几乎为反位相,东北地区的低频降水落后于高原低频纬向风约1/4位相;高原西风减弱年份,江淮以北的我国北方大部分地区低频降水与高原低频纬向风几乎同位相,江淮地区的低频降水落后于高原低频纬向风约1/4位相.低频降水与低频环流有较好的配置关系.

选取成蝇较易出现的公园和居民区环境类型,采用腐鱼笼诱法分别于2002与2013年对上海中心城区世博建设前后蝇类群落构成和季节消长状况进行监测并对比分析.结果显示,与2002年相比,2013年居民区环境蝇密度显著下降,捕获的蝇种类总数稍有上升;最优势蝇种由2002年的丝光绿蝇转变为2013年的大头金蝇(当年构成比分别为46.06%和20.50%),亮绿蝇、元厕蝇的密度及构成比较2002年显著上升.2002与2013年成蝇高峰分别均出现于6月份,2013年夏季气温高热造成7月份出现一个波动较大的低谷;丝光绿蝇在不同年代的季节分布差异较明显,其他蝇种分布趋势前后较吻合.据此推论上海城区蝇类侵害以丽蝇科为主,不同监测环境差异较大;城区卫生环境的改善对减少住区蝇滋生起了重要作用,但人口密度高、部分老城区环境复杂、各行业所产生垃圾较多而容易造成蝇类滋生侵害的状况依然存在,蝇类防控措施应针对金蝇和绿蝇等优势蝇种开展,防控工作任重而道远.

河鲈锚首虫Ancyrocephalus mogurndae是主要寄生于鳜鱼Siniperca spp.鳃上的一种单殖吸虫,此虫严重危害鳜鱼苗种,流行于珠江三角洲地区.2011年9月至2012年8月,对广东省肇庆市池塘养殖斑鳜Siniperca scherzeri寄生的河鲈锚首虫进行了一周年的种群动态研究,共检查斑鳜322尾.结果显示:斑鳜河鲈锚首虫的感染率在春夏两季较高,秋季较低,年均感染率为91.2%,其中有6个月达到了100%.其平均感染强度和平均丰度无明显的周年变化;感染率、平均感染强度和平均丰度与水温没有明显的相关关系,但河鲈锚首虫的感染强度与斑鳜的肥满度之间存在极显著的负相关关系.

为了解中哈边境阿拉山口口岸地区蚊虫种群本底构成及生态习性,采用帐诱、挥网、灯诱采集蚊虫,进行形态学分类鉴定.2012与2013两年共采集成蚊16 317只、经随机抽样鉴定3 370只,隶属2科5属11种.2013年比2012年增加了2种,比历史资料记录的增加了5种,其中凶小库蚊占蚊虫总数的46.0%,为当地优势种.其生境季节变化从3月开始活动,5月达到高峰,8月为次高峰,至11月活动消失.调查结果显示应重视对优势蚊种的防控及携带病原的研究,识别外来物种的入侵、蚊媒疾病的监控提供了基础资料.

Life-history theory predicts that in hibemators age of maturation is related positively to body size and negatively to the duration of active season aboveground. Yellow souslik is a large-sized ground squirrel with long hibernation, which suggests late maturation. We used four-year field observations of marked individuals to determine the age of maturation in males through analysis of age-dependent variation in body size, mass, androgen status, timing of spring emergence, ranging patterns and social behavior during the mating season. Yearling males were smaller, lighter, had lower level of fecal testosterone, emerged later and had smaller home ranges than older males. Social activity and the number of females encountered did not differ between age classes. After the second hibernation none of the studied parameters varied with age. Cluster analysis revealed two behavioral tactics: "active" males (adults only) emerged earlier, ranged more widely, initiated more contacts, encountered more females and were heavier than "passive" males (both yearling and adult). Thus, males of S. fulvus reached adult size and matured after two hibernations, which is relatively fast for such a big species with short active period. Indirect evidence for copulations and high variation among yearlings in all parameters suggest that some of them might successfully compete with adults. Active tactic of wandering and searching for females is energetically costly, and probably only adult males in good physical condition can afford it, whereas passive tactic of residing is energy saving and good for adults in poor condition and for yearlings that are continuing to grow.

对干生活在中高纬度地区的人们而言,季节变化是决定几乎所有生活生产活动的主要驱动因子.从远古时期开始,我们的祖先就以生命的代价换取和积累了对不同季节条件下,不同植物、动物生活规律的宝贵知识和经验,为人类后代生存、延续和发展提供了必需的食物来源.我国先人发现的二十四节气至今还影响着现代农业活动的各个环节.在现代科技条件下,