Simimys and origin of the cricetidae (Rodentia: Muroidea)

Simimys is a late Eocene and earliest Oligocene genus that shares dipodoid (zygoma) and muroid (dental) characters. The Oligocene record of dipodoid rodents includes Plesiosminthus from middle Oligocene deposits of Asia and late Oligocene deposits of Europe. The Oligocene record of muroid rodents includes at least two genera (Eucricetodon and (Cricetops)) from Asia, six genera (Eucricetodon, Pseudocricetodon, Melissiodon, Paracricetodon, Heterocricetodon and Adelomyorion)) from Europe, and three genera (Eumys, Scottimus and Nonomys)) from North America. The known record, as given above, suggests that Siminys is the earliest and most primitive genus with muroid affinities; it also implies that muroid rodents were derived from unknown Eocene dipodoid rodents.The Oligocene cricetid rodents display progressive expansion and inclination of the anterior plate of the zygoma. These changes in the zygoma probably reflect evolutionary stages in the development of a myomorphous zygoma from an hystricomorphous zygoma. Changes in the zygoma apparently took place at different rates and times in Asia. Europe, and North America; they probably reflect differenciation of Cricetodontinae in Palaearctica, and Eumyinae in Nearctica during the Oligocene.     

鄱阳湖区灰鹤越冬种群数量与分布动态及其影响因素

1998—2011年,采用地面同步调查法开展了鄱阳湖越冬灰鹤种群监测,并整合1984—2011年鄱阳湖国家级自然保护区历年的越冬灰鹤最大种群数量,分析了鄱阳湖灰鹤越冬种群动态以及影响其数量变化与空间分布的环境因素。结果表明,近13年来鄱阳湖区越冬灰鹤种群平均数量为(2 335±651)只,种群数量呈增长趋势,2011年冬季记录到最大种群数量7 640只。灰鹤越冬种群数量与10月平均最低气温以及10月平均气温存在显著正相关,与10月平均最大风速存在显著负相关,与各月的平均水位没有显著的相关性。每年冬季灰鹤在鄱阳湖呈聚集型分布。大湖池、大莲子湖、三湖、汉池湖、企湖、珠湖、南湖(共青)、大汊湖等8个湖泊是灰鹤的重点活动区,(74.9±5.6)%的越冬灰鹤分布在保护区之外。灰鹤的空间分布与滩地面积存在显著的正相关,与农田面积、人口密度、村庄数量、8月份初级生产力、11月份初级生产力等环境因子存在显著负相关。滩地面积是影响灰鹤空间分布的重要因子,对灰鹤利用频次空间变化的解释率为15.0%,与11月份初级生产力共同解释了灰鹤年平均群体数量空间变化的24.6%。如竞争、小生境结构、干扰等局地尺度的环境要素对灰鹤空间分布的影响研究将有助于更全面地认识鄱阳湖越冬灰鹤种群动态的影响机制。     

云南纳帕海越冬黑颈鹤日间行为模式与年龄和集群的关系

2006年10月—2007年5月,在云南省西北部纳帕海,采用路线调查结合瞬时扫描行为取样法,对越冬黑颈鹤(Grus nigricollis)种群的时间分配及其与年龄、集群和时间的关系进行了观察。结果说明,黑颈鹤越冬活动主要是以觅食为主,占日间时间的(76.81±9.1)％。越冬期间黑颈鹤日间行为的节律性较为明显,具有适应高寒气候的特点。集群形式对成鹤的行为有着显著影响,集群和家庭中活动的成鹤在觅食、警戒和争斗中存在显著差异(F1,76= 0.27、0.77, U= 279, P= 0.001—0.000)。年龄是影响鹤群行为的因素之一。幼鹤相比成鹤有较多的觅食时间和休息时间,警戒行为比例较低(F1,76= 0.04—2.59, U= 188—299, P= 0.006—0.000),且不受集群形式的影响。随着越冬期间的早、中、晚3个时期的环境变化,黑颈鹤的时间分配有显著变化(F2,36= 4.63—26.54, 22= 5.29—13.68, P= 0.0016—0.000)。不同越冬地的黑颈鹤行为存在差异。气候、食物资源和人为影响可能是造成这些差异的主要因素。     

白鹤中途停歇地主要食物藨草球茎密度的空间插值方法研究

扁杆藨草(Scirpus planiculmis)和三江藨草(S.nipponicus)的球茎是迁徙白鹤(Grus leucogeranus)在莫莫格中途停歇地的主要食物。2010年9月15～25日,对莫莫格白鹤集中停歇地鹅头泡湿地的20条样线上100 m等间隔470个取样点进行了地下0～20 cm的藨草球茎的取样工作。基于此,采用反距离权重、4种径向基函数和普通克里格共6种空间插值方法模拟了该区域藨草球茎密度。交叉验证和插值结果的空间分布图对比,径向基函数中的张力样条插值效果最佳,是最适于该区域挺水植物藨草球茎密度的空间插值方法。张力样条插值结果表明:研究区内藨草球茎密度均值为(46.0±44.3)个/m2。其中,<25个/m2的面积占研究区的41.7%,25～100个/m2的面积占45.9%,而>100个/m2的面积仅占12.4%。研究结果为下一步分析白鹤迁徙种群与环境因子的生态关系、预测该地区白鹤的环境容纳量提供十分重要的基础数据。     

THE VOCAL REPERTOIRE OF THE GREY CROWNED CRANE BALEARICA REGULORUM GIBBERICEPS. I: THE TONAL AND THE NON-HARMONIC CALLS

ABSTRACT

The study describes the vocal repertoire of the Grey Crowned Crane Balearica regulorum gibbericeps and speculates on the purpose the calls serve. The repertoire consists of 4 tonal and 7 non-harmonic calls. Chicks have 3 different vocalizations.     

农业耕作活动对西藏越冬黑颈鹤食性及食物可获得性的影响

于1996年1月对西藏中南部越冬黑颈鹤的食性和谷物性食物的可获得性进行了研究。青梨（Hordeum vulgare),春小麦（Triticum spp.),冬小麦（Triticum spp.)是该地区的3种主要作物。对黑颈鹤粪便的分析表明,越冬黑颈鹤取食大量的农作物,尤其是小麦散落从粒,而冬小麦苗仅上鹤类食物组成的很小一部分。秋收后的翻耕,放牧等农业活动影响地面上作物残物（种子,叶,秆或根）及谷粒残物（裸粒,穗稃）的数量,农地翻耕掩埋了大部分的作物残物。未翻耕青梨地与小麦地上的作物残物覆盖比值相似。谷物残物的密度在未翻耕的小麦地上最大,为了最大限度地增加黑颈鹤的冬季食物来源,减少人为活动对黑颈鹤的干扰,我们建议：在秋收后不要翻耕河流两侧的青梨地和小麦地;在冬小麦种植地区,冬小麦应仅仅种植在主要公路两侧。     

Carbon Dioxide Exchange Between an Old-growth Forest and the Atmosphere

Eddy-covariance and biometeorological methods show significant net annual carbon uptake in an old-growth Douglas-fir forest in southwestern Washington, USA. These results contrast with previous assumptions that old-growth forest ecosystems are in carbon equilibrium. The basis for differences between conventional biomass-based carbon sequestration estimates and the biometeorologic estimates are discussed. Annual net ecosystem exchange was comparable to younger ecosystems at the same latitude, as quantified in the AmeriFlux program. Net ecosystem carbon uptake was significantly correlated with photosynthetically active radiation and air temperature, as well as soil moisture and precipitation. Optimum ecosystem photosynthesis occurred at relatively cool temperatures (5°–10°C). Understory and soil carbon exchange always represented a source of carbon to the atmosphere, with a strong seasonal cycle in source strength. Understory and soil carbon exchange showed a Q₁₀ temperature dependence and represented a substantial portion of the ecosystem carbon budget. The period of main carbon uptake and the period of soil and ecosystem respiration are out of phase, however, and driven by different climatic boundary conditions. The period of strongest ecosystem carbon uptake coincides with the lowest observed values of soil and ecosystem respiration. Despite the substantial contribution of soil, the overall strength of the photosynthetic sink resulted in the net annual uptake. The net uptake estimates here included two correction methods, one for advection and the other for low levels of turbulence.     

有机氯农药在东方白鹳和白鹤羽毛中的残留分析

2007年5月,采集合肥野生动物园采集东方白鹳(Ciconia boyciana)及白鹤(Grus leucogeranus)的胸部廓羽、飞羽及尾羽样品共51枚,用气相色谱法分别检测其中的op’-DDT、pp’-DDD、pp’-DDE、pp’-DDT、α-六六六、β-六六六、γ-六六六、δ-六六六及六氯苯9种有机氯农药的残留量。检测结果发现,pp’-DDD、pp’-DDE、pp’-DDT、β-六六六、δ-六六六5种有机氯农药在东方白鹳和白鹤羽毛中都有不同程度的检出,其中pp’-DDD的残留量最高,在东方白鹳的廓羽、飞羽和尾羽中的平均残留量分别达到0.8936、0.8353和0.7516μg/g干重,在白鹤的廓羽、飞羽和尾羽中的平均残留量分别达到0.5685、0.5077和0.4657μg/g干重;pp’-DDD和pp’-DDT在两种鸟胸部廓羽、飞羽及尾羽间的残留量无显著差异;pp’-DDD在东方白鹳飞羽和尾羽中的残留量显著高于白鹤。