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11.
自2001-2006年,中国科学院与英国鸟类研究中心联合对新疆准噶尔盆地和昆仑山、青海玉树地区、西藏那曲地区的猎隼(Falco cherrug)分布状况与繁殖生态进行深入调查。考察行程上万公里。卫星跟踪显示在俄罗斯、蒙古繁殖的猎隼迁往青藏高原越冬。但是,实地调查表明,在新-青-藏还有一些繁殖种群;繁殖区的海拔高度从600 m,上升至5 200 m。根据观察,猎隼喜欢沿用旧巢,多数巢属于"垃圾巢"。因为高原缺乏合适的巢材,那些人类遗弃的皮管、铁丝、皮带、破布、汽车零件、骨片、绳子等垃圾充斥于巢穴之中。考察期间,共找到100多只猎隼成鸟、约35个猎隼巢或巢区;分布地点涉及昆仑山脉、准噶尔盆地、卡拉麦里山脉、北塔山、可可西里、唐古拉山脉等,包括新疆奇台、且末、青河、塔城,青海楚玛尔河、五道梁、曲麻莱、雁石坪、玉树,西藏安多、那曲等。猎隼巢址多位于悬崖凹陷处(21个)、河岸砂土洞(5)、桥梁(2)等处;巢高于地面7~30 m。通常沿用渡鸦、大鵟、棕尾鵟、金雕的旧巢,有同步繁殖现象。附近有鼠兔、雪雀、地鸦、岩鸽、石鸡、沙鸡等活动。巢区沿着山脉或者丘陵连续分布,巢间距最近2.5 km,通常4~8 km或更远。在准噶尔盆地其繁殖密度1.1~1.6对/1 000 km2。通常4~5月产卵,窝卵数3~5枚;5月上旬和中旬已有部分幼鸟出壳。虽然在中国捕捉猎隼现象十分猖獗,但考察结果依然令人振奋。建议中国猎隼研究小组(CSRG)积极开展国际合作,通过卫星跟踪、GPS定位、电子微芯片标记(PIT)、DNA指纹图谱分析、人工猎隼栖架和巢穴招引技术等,不断完善监测手段和管理机制,为猎隼的保护与合理利用做出努力。 相似文献
12.
The effect of vertical turbulent mixing on the dynamics of persistent organic pollutants has long been overlooked and its role is still hardly understood. Here we present the first comprehensive analysis of the role of turbulent diffusion on the distribution of those contaminants and its interplay with sinking fluxes. To this end, a 1D dynamic coupled hydrodynamic-contaminant model has been developed and applied to a Mediterranean continental shelf environment. The hydrodynamic sub-model is adapted from COHERENS, the contaminant sub-model is an improvement from the BIODEP model and considers the contaminant in 3 phases: dissolved-colloidal-particulate. The simulation highlights the role of turbulence in determining the POP distribution and variability in the water column. In short, turbulent flux of contaminants strengthens the upward diffusion of sediment entrained contaminants and determines the extent to which inputs from the atmosphere mix into the water column. It acts in parallel with degradation and sinking fluxes, the combined effect yielding a surface enriched - depth depleted - benthic layer enriched region distribution, which presents similarities to reported experimental measures. 相似文献
13.
Dimitar Marinov Ingrid Puillat Elena Jurado Jordi Dachs 《Marine pollution bulletin》2009,58(10):1554-1561
Spatio-temporal variability of pollutants in the environment is a complex phenomenon that requires a combined approach for its analysis. Whereas data on measured levels of contaminants in various environmental compartments is essential, it is not always possible to monitor at the necessary frequency and with the adequate spatial sampling distribution to capture this variability. Therefore a modelling approach able to complement experimental data and close the gaps in the monitoring programs is useful for assessing the contaminant dynamics occurring at different time scales. In this work a 1D water column fate model has been developed and tested for Polycyclic Aromatic Hydrocarbons (PAHs). The model has been coupled with a simple ecological model that includes a bioaccumulation module. Afterwards, the model has been used to study the temporal variability of contaminant concentrations as well as the fluxes between compartments. The results evidence the complex coupling between spatio-temporal scales and its influence on environmental concentration levels. 相似文献
14.
Emanouil Atanassov Aneta Karaivanova Todor Gurov Sofiya Ivanovska Mariya Durchova Dimitar Sl. Dimitrov 《Earth Science Informatics》2010,3(4):289-296
In this paper we present error and performance analysis of quasi-Monte Carlo algorithms for solving multidimensional integrals
(up to 100 dimensions) on the grid using MPI. We take into account the fact that the Grid is a potentially heterogeneous computing
environment, where the user does not know the specifics of the target architecture. Therefore parallel algorithms should be
able to adapt to this heterogeneity, providing automated load-balancing. Monte Carlo algorithms can be tailored to such environments,
provided parallel pseudorandom number generators are available. The use of quasi-Monte Carlo algorithms poses more difficulties.
In both cases the efficient implementation of the algorithms depends on the functionality of the corresponding packages for
generating pseudorandom or quasirandom numbers. We propose efficient parallel implementation of the Sobol sequence for a grid
environment and we demonstrate numerical experiments on a heterogeneous grid. To achieve high parallel efficiency we use a
newly developed special grid service called Job Track Service which provides efficient management of available computing resources through reservations. 相似文献
15.
Ground-based observations of the spectral sky radiance within the totality region during a total solar eclipse are of significant interest because the contribution from direct and single scattered light from the solar disk is eliminated. In the present paper, we develop a numerical model of the spectral sky radiance during totality, evaluate the contribution of double scattered sunlight to the sky radiance at totality and compare it to solar corona emissions. The results show that the single scattered coronal light is the major contaminant in ground-based observations of the corona, opposite to what was believed before. For observation directions outside the corona the double scattered sun radiation dominates over the single scattered coronal light. 相似文献
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George D. Djolov Dimitar L. Yordanov Dimitar E. Syrakov 《Boundary-Layer Meteorology》1987,41(1-4):407-416
An improvement of long-range air pollution transport and diffusion model which includes planetary boundary layer (PBL) dynamics and chemistry of SO2 and NOx, the processes of dry and wet deposition has been developed and used in the Southeast Europe. The transport and diffusion process are described on the basis of a combination of the Eulerian and Lagrangian approaches. A similarity theory is used for calculation of the PBL characteristics. A known linear chemistry module which includes 5 nitrogen and 2 sulphate species is incorporated. The model results for the region of Southeast Europe are in good agreement with the Meteorological Synthesizing Center West, Oslo information. 相似文献
18.
2005年4月至6月,在新疆准噶尔盆地东部地区对棕尾鵟的繁殖生物学进行了研究.通过对棕尾鵟(Buteo rufinus)10个巢的观察,发现巢体大多在山体阴面.对棕尾鵟的26枚卵进行测量,长径是56.24 mm±2.58 mm,短径是43.10 mm±0.93 mm.通过对亲鸟孵卵及育雏情况的观察,此地区棕尾鵟的窝卵数2～4枚,孵化率是0.433,幼鸟成活率为0.692,棕尾鵟繁殖力为0.499.在研究中发现,巢内的毛皮、布片、塑料袋等铺垫物由于被风吹起盖住卵而导致亲鸟弃巢的现象严重.10只卵由于巢内铺垫物的覆盖而导致孵化失败. 相似文献