济南泉域地下水污染现状及对策研究

随着经济的快速发展和工业化、城市化进程的不断加快和人口的剧加,人类活动产生的污染物对济南市局部地下水造成了一定的污染。该文分析论述了济南市泉域的水文地质条件,地下水污染现状及综合评价,提出了防治地下水污染的措施。     

敦煌月牙泉景区沙丘粒度特征

对月牙泉外围沙山表面沉积物进行系统采样,结合区域风况,分析了沙山典型部位的粒度分布及其参数特征。月牙泉北侧金字塔沙丘沙粒较粗,分选性较差,正偏趋势显著;月牙泉南侧线形沙丘以细沙为主,分选性较好,分布属正偏态。北侧金字塔沙丘从西南和西北两个坡面到东侧坡面,粗颗粒减少、分选性变好,但趋势不明显,说明金字塔沙丘未发生明显移动;而南侧线形沙丘自南侧坡面向北侧坡面沙粒粒径变小、分选变好,较细的沙粒被搬运并沉积北侧坡面,搬运作用十分明显,即线形沙丘向月牙泉方向发生明显移动。通过粒度分析风沙动力环境表明,月牙泉风沙危害主要来自南侧沙山北移。     

金字塔沙丘近地表流场及其对月牙泉影响研究

对月牙泉景区气象站点资料和积沙量统计分析以及月牙泉北侧金字塔沙丘近地表流场野外观测表明：受地形影响,月牙泉景区和金字塔沙丘各点起沙风玫瑰和输沙势玫瑰在监测期内差别较大。在金字塔沙丘影响下,不同风向下气流发生多次分离和汇集,沙丘近地表气流发生明显变化,携沙气流行进方向发生改变。金字塔沙丘坡面上各点合成输沙势和起沙风与坡面走向呈垂直角度,气流沿坡面爬越沙丘时,动能发生损耗,携沙能力减弱,减少了进入月牙泉的风沙量,减弱了月牙泉的风沙灾害。     

MJO对中国春季降水影响的数值模拟研究

利用IAP-AGCM4.0模式,通过多初值集合数值模拟研究了赤道附近的大气季节内振荡(MJO)传播的两个关键位相期对中国东部春季降水的影响.当在赤道中东印度洋及赤道西太平洋引进异常非绝热加热(强MJO活动)强迫时,模式很好地模拟出了中国东部地区春季降水的异常形势,模式模拟与先期所作的诊断分析结果极为相似,即在MJO的第2-3(6-7)位相,中国长江中下游地区多雨(中国东部大部分地区降水偏少).对模式输出的高度场、风场、散度和涡度场以及水汽输送场的分析表明,中国春季降水异常的发生分别与异常非绝热加热在东亚/西北太平洋地区所造成的异常大气环流形势密切相关.对逐日响应场的分析表明,就MJO活动影响中国春季降水的可能物理过程及机制进行的讨论表明,赤道附近的异常对流加热不仅可以在赤道附近激发产生大气的罗斯贝波和开尔文波型响应,而且,还会在大气中激发产生从热带到中高纬度的罗斯贝波列遥响应.但是,由于异常对流加热发生的地区不同,大气遥响应场的形势也会十分不同,它所导致的影响也就很不一样.当异常对流加热发生在赤道中东印度洋(对应MJO的第2-3位相)时,大气的罗斯贝波列遥响应将在东亚/西太平洋地区形成有利于中国东部(尤其是长江中下游地区)春季降水偏多的形势;当异常对流加热发生在赤道西太平洋(对应MJO的第6-7位相)时,大气的罗斯贝波列遥响应将在东亚/西太平洋地区形成不利于中国东部春季降水的形势.     

基于地下水流场和含水介质分析的敦煌月牙泉成因研究

在分析月牙泉多年动态变化趋势的基础上,依据最新水文地质勘探资料和编绘的月牙泉周围年丰水期、枯水期地下水等水位线图,从地下水流场和含水介质的角度分析研究了月牙泉形成原因。月牙泉上游地下水基本呈自西南向东北径流,在地势低洼的沙漠丘间地带出露形成月牙泉;地下水补给来源为上游党河右岸黑山咀子东侧浅层地下潜水的侧向径流,黑山咀子至月牙泉之间的地下水水力坡度在丰水期为4. 813‰,枯水期为 4. 622‰;月牙泉泉水与周边地下水是统一的水力系统;月牙泉附近含水层是党河冲洪积层的连续的过渡关系,泉水出露形成是含水层与特殊地形地貌结合的产物。     

GMS在白泉湿地公园地下水数值模拟中的应用

为探究白泉湿地公园建设过程中白泉湖开挖对白泉的影响,在系统分析白泉泉域水文地质条件的基础上,采用地下水数值模拟专业软件GMS建立2012—2014年白泉泉域地下水流数值模型。在此基础上,利用10年平均和10年典型2种降雨情景对公园建成前、后白泉水位和流量进行预测。通过对比分析,结果表明公园建成后未来10年白泉可以保持持续喷涌,不会有断流情况的发生。在保证白泉湖景观用水的前提下,每天至少有100 m^3的泉水通过河道排泄到小清河。白泉湿地公园建成后,随着附近地下水的进一步减采,白泉的流量将逐渐增大,白泉湖的景观水位更加有保障。     

The harpacticoid assemblages (Copepoda: Harpacticoida) in the Western Carpathian spring fens in relation to environmental variables and habitat age

Harpacticoids are an important component of meiofaunal assemblages in springs. No information so far has been available on harpacticoid assemblages of the Western Carpathian spring fens, unique biotopes of high conservation value which cover a very long gradient of mineral content of groundwater, due to the variable geological background setting. Spring fens are isolated habitats of different age which can be assessed by radiocarbon dating of their basal sediment layers. This enables to test a possible effect of habitat age on species composition and species richness. In this study, we examined harpacticoid assemblages in 50 permanent tree-less spring fens (helocrenes) in the Western Carpathians (Slovakia and Czech Republic) in terms of species composition, total abundance, species density, and species richness. We tested mainly the effect of 12 explanatory variables describing water chemistry and temperature, climatic conditions, amount of nutrients, organic carbon, sediment structure, habitat age and size, using Canonical Correspondence Analyses (CCA) with stepwise forward selection. For the computation of species richness rarefaction was used. In total, 20 harpacticoid species were recorded with the total median density of 950 individuals in m⁻². Three significant explanatory variables, Ellenberg Indicator Values of plant community for nutrients, in situ measured pH, and average January temperature, explained together 19.0% (adj. 13.7%) of the total variance in the species composition data. The relationships of harpacticoids to these three explanatory variables were species specific and no uniform response of the total assemblage to the environmental variables was found (in terms of total abundance and number of species). The only exception was the influence of overall unfavourable conditions in the mineral-poor acidic Sphagnum-fens. Pilocamptus pilosus was significantly associated with a higher amount of nutrients and warmer climate. Nutrient enrichment was clearly indicated by a decrease or absence of crenophile Bryocamptus cuspidatus, and accompanied by an increase in ubiquitous Attheyella crassa. Moraria brevipes was confined to low pH, B. cuspidatus showed a high tolerance for low pH, whereas Bryocamptus echinatus preferred alkaline conditions. Despite a significant correlation between habitat age and species density we found no clear evidence that any colonisation driven process could influence the number of harpacticoid species within the tested time scale. We hypothesize that rather other habitat characteristics connected with age, i.e. habitat heterogeneity and stability, may be determinant for species richness. The occurrence of some species (e.g. P. pilosus, B. cuspidatus) was clearly geographically limited, but due to the spatial structuring of significant environmental variables no conclusion on dispersal limitations could be made.     

敦煌鸣沙山-月牙泉近地表风沙输移路径及强度

利用鸣沙山-月牙泉景区多点同步风况和输沙通量资料,探讨了近地表流场特征、风沙活动强度及输移路径;基于1985和2009年两期遥感影像,揭示高大沙山动态变化及其对月牙泉的影响。月牙泉主要受南北沙山夹击,尤其是北沙山南移更为突出,直接威胁月牙泉存在。近年来,受地形、周边建筑物和外围树木的影响,月牙泉景区近地表流场改变,导致区域输沙动态平衡破坏。因此,月牙泉风沙防治应从恢复近地表风沙流场角度考虑,遵循风沙动态平衡原则,打通月牙泉景区东风通道,恢复均衡环流结构,这是维系高大沙山与月牙泉共存的关键。     

科尔沁沙地玉米耗水规律初探

运用蒸渗仪对沙地玉米的耗水量做了测定研究。结果表明,玉米在本地区的耗水量为464.6mm,其中播种-拔节期为67.7mm,拔节-抽穗期为164.4mm,抽穗-灌浆期为102.2mm,灌浆-成熟期130.3mm;水分生产率为10.84kg·hm^-2·mm^-1;沙地玉米田的日蒸散曲线在苗期和拔节期呈现抛物线型,但在抽穗和灌浆期则为一个双峰曲线;本地区的降水不能满足玉米的生长需要,需灌溉予以补充。