“中国死海”——运城盐湖创新之路

随着旅游休闲时代的到来,集旅游、文化修养、保健于一身的休闲度假游日益成为人们出行的重要选择目的之一。"中国死海"——运城盐湖顺应时代发展潮流,成为了山西休闲度假游的亮点。为了实现其持续、稳定、健康的发展,旅游纪念品设计、旅游形象口号、旅游产品营销以及环境保护将是当地旅游部门的重要任务。     

渼陂历史地理初探

渼陂位于西安户县境内。汉代时为上林苑十池之一,又称西陂。唐宋时期渼陂集游览、农田灌溉、发展碾硙、鱼类养殖于一体,负有盛名。从诗文及其他古籍记载来看,元代以前渼陂的面积相当可观。至元末遭游兵决堤,逐渐缩小,沦为稻垅。明清两代又得以重建,但面积仍然有限。元末以降,渼陂衰落的主要原因来自于游兵的破坏,但渼陂水源的枯竭也不失为其衰微的一个原因。     

基于LEGOS HYDROWEB的青藏高原湖泊群水位和面积动态变化分析

湖泊面积和水位的变化客观地反映了区域水资源的时空变化过程。利用LEGOS HYDROWEB提供的湖泊信息数据,对青藏高原1993~2014年21年间63个典型湖泊的水位变化,以及其中59个湖泊的面积变化趋势进行分析。根据变化趋势将湖泊分为增长型、稳定型和衰退型;并在这三种类型的湖泊中分别选取两个典型湖泊进行回归分析。结果表明:63个湖泊中水位增长型湖泊42个,稳定型湖泊12个,衰退型9个;59个湖泊中面积增长型湖泊32个,稳定型19个,衰退型8个。对于增长型湖泊而言,水位和面积增长最大是Ziling湖,分别增长了10.90 m和361.72 km~2;衰退型湖泊中水位和面积衰退趋势最大的是Yamzho-yumco湖,分别减少了2.29 m和28.65 km2。高原内陆水体的水位和面积的动态变化对研究气候演变和地表水资源的影响具有重要意义。     

基于专家分类器的洪泽湖湿地变化分析

利用1989年、1995年、2000年和2009年4期洪泽湖地区的TM图像,基于专家分类器从光谱和空间特征多方面制定规则,分析遥感影像上洪泽湖湿地及湿地内部各种类型的分布和变化.研究结果表明:①用专家分类器可以更好的提取出洪泽湖湿地及湿地内部耕地、养殖场、湿地植被和敞水区等分布及其变化;②在研究期内,洪泽湖湿地面积总体上呈现一种先降后升的趋势.1989-2009年间洪泽湖湿地内的耕地和养殖场的面积分别增加了3.40倍和2.64倍,湿地植被和水体面积在研究期间分别减少了18%和15%.     

鄱阳湖松门山岛砂质沉积颗粒表面特征及环境指示意义

沉积物沉积环境的判别对于沉积物物源的分析、古地理重建、古环境和古气候的恢复均具有重要的意义。通过研究发现鄱阳湖松门山岛沉积颗粒表面具有丰富的特征,主要是:贝壳状断口、V形撞击坑、撞击沟、碟形撞击坑与新月形撞击坑等。利用扫描电镜对鄱阳湖松门山岛的样品进行了研究,发现鄱阳湖松门山岛的水下砂体样品普遍可见贝壳状断口、V形撞击坑与撞击沟等,说明该类样品为水成环境;沙丘样品普遍可见标准的碟形撞击坑与新月形撞击坑等,说明为风成环境;处于水下砂体和沙丘过渡带之间的样品上述现象几乎均存在,说明这些沉积物经过风成和水成两种环境的共同改造。分析水成和风成环境下的石英颗粒的不同特征,对这些特征利用线测法进行统计分析,发现不同环境下石英颗粒的特征不仅可以定性判别,还可以半定量区分:在水成环境下的样品撞击沟所占的比值高,通常大于30%,而在风成环境中的样品碟形坑所占的比值高,通常大于40%。这一发现对该地区的沉积环境分析有指导作用,并且对于该地区沉积微相划分具有一定意义。     

菜子湖鱼类区系变动及其驱动力分析

2007～2008年对菜子湖鱼类多样性和渔业方式进行了调查,采集到鱼类8目18科68种,包括3种新记录.历史记录的13种洄游性鱼类本次仅见2种野生群,湖区野生洄游性鱼类经济绝灭.养殖鱼类产量占渔业总产的91.4%,成为渔业主体.杂食性鱼类物种丰富但产量甚微,相反人工放流的鲢、鳙等滤食性鱼类产量达鱼类总产的68.6%,为绝对优势种.湖区鱼类区系组成的特征变化与江湖阻隔和渔业养殖模式变革密切相关,因此江湖关系变动及渔业养殖当为菜子湖鱼类区系变动的关键驱动因子.     

Molecular characterization of H3N2 and H4N6 subtypes avian influenza viruses isolated from mallards in Poyang Lake, China in 2010

Poyang Lake is the largest inland freshwater lake in China and contains many species of wild birds and waterfowls.We conducted a survey of avian influenza viruses in nine semi-artificial waterfowl farms in Poyang Lake during January to March of 2010.Out of 1036 cloacal swabs collected,three H3N2 and one H4N6 influenza viruses were isolated from healthy mallards.All the isolates were genetically and phylogenetically characterized.The analysis of putative HA cleavage sites showed that all the four isolates possessed the molecular characteristics(QTRGL for H3N2 viruses,PEKASR for H4N6 virus) of lowly pathogenic avian influenza(LPAI) virus.The phylogenetic analysis of the viral genomes showed that all four virus isolates clustered in the Eurasian clade of influenza viruses.The M gene of the viruses possessed the highest homology with highly pathogenic H5N1 influenza viruses.In addition,co-infection of H3N2 and H4N6 in the same farm was observed.And interestingly,we isolated two subtypes viruses(H3N2 and H4N6) and their progeny virus(H3N2) with evidence of genome reassortment from the same farm,in which the PB1 and PB2 gene segments of H4N6 replaced those of the H3N2 strain.The results of animal infection experiments showed that all the four isolated viruses were lowly pathogenic to chickens and not pathogenic to mice,which was consistent with the results of genetic analysis.     

Changes in palaeoproductivity of Genggahai Lake over the past 16 ka in the Gonghe Basin, northeastern Qinghai-Tibetan Plateau

Sequential samples of a 7.82-m sediment core from Genggahai Lake in the central Gonghe Basin,controlled with 12 accelerator mass spectrometry (AMS) 14 C dates,have been analysed for total organic carbon (TOC) and total nitrogen (TN) contents,carbon isotope of bulk organic matter (δ 13 C org),and carbonate content.Plant macrofossils and stem encrustations,derived mainly from the species of P.pectinatus,M.spicatum and Chara spp.,were identified,and they dominated the aquatic plant community of the lake.Alternations of plant macrofossils of Chara spp.and the vascular species reflect the changing productivity of the lake over time.In such a shallow lake,the carbonate content is highly related to photosynthesis of aquatic macrophytes and thus indirectly indicates variations in productivity,consistent with a quantitative estimate of palaeoproductivity.Based on these results,the palaeoproductivity history was reconstructed over the past ca.16 ka.The lake was formed or recharged at 15.3 cal ka BP,as indicated by aeolian sand deposits at the core base.A marked increase in palaeoproductivity occurred from 15.3 to 11.6 cal ka BP.Between 11.6 and 9.2 cal ka BP,a sharply increased water-level,modulated probably by the enhanced Asian summer monsoon,might have exceeded the optimum water depth for macrophyte vegetation,causing a marked decline in coverage of aquatic macrophytes and low palaeoproductivity.The palaeoproductivity appeared to be high in the early stage of the period from 9.2 to 7.4 cal ka BP,and then decreased at approximately 8.6 cal ka BP.The palaeoproductivity sustained an overall high level between 7.4 and 2.1 cal ka BP,and decreased gradually since 2.1 cal ka BP.Our results suggest that the variability of Genggahai Lake palaeoproductivity may be associated with fluctuations of the lake level controlled by the strength of the Asian summer monsoon,probably indicating changes in the Asian summer monsoon.     

洞庭湖区现代农业发展财政支农资金整合问题研究

整合各种财政支农资金,不断提高资金使用效率,不仅使中央和地方政府实施的各项强农惠农富农政策得以完善与巩固,也有利于促进现代农业的发展。洞庭湖区整合财政支农资金具有重要的现实意义;就目前情况来看,整合财政支农资金促进了湖区现代农业发展;今后要通过若干保证措施来继续加大财政支农资金整合力度,促进湖区现代农业进一步发展。