Tephra Discovered in High Resolution Peat Sediment and Its Indication to Climatic Event

Floating tephra was deposited together with ice core,snow layer,abyssal sediment,lake sediments,and other geological records.It is of great significance to interpret the impact on the climate change of volcanic eruptions from these geological records.It is the first time that volcanic glass was discovered from the peat of Jinchuan(金川)Maar,Jilin(吉林)Province,China.And it is in situ sediments from a near-source explosive eruption according to particle size analysis and identification results.The tephra were neither from Tianchi(天池)volcano eruptions,Changbai(长白)Mountain,nor from Jinlongdingzi(金龙顶子)volcano about 1 600 aBP eruption,but maybe from an unknown eruption of Longgang(龙岗)volcano group according to their geochemistry and distribution.Geochemical characters of the tephra are similar to those of Jingiongdingzi,which are poor in s.Jica,deficient in alkali,Na20 content is more than K20 content,and are similar to distribution patterns of REE and incompatible elements,which helps to speculate that they originated from the same mantle magma with rare condemnation,and from basaltic explosive eruption of Longgang volcano group.The tephra,from peat with age proved that the eruption possibly happened in 15 BC-26 AD,is one of Longgang volcano group eruption that was not recorded and is earlier than that of Jinglongdingzi about 1 600 aBP eruption.And the sedimentary time of tephra is during the period of low temperature alteration.which may be the influence of eruption toward the local climate according to the correlativity of eruption to local temperature curve of peat cellulose oxygen isotope.     

惰性气体法测定地下水入渗补给量

地下水入渗补给量是重要的水文地质参数。本文介绍了测定地下水入渗补给量的最新方法——惰性气体法的原理与方法，该方法适用于封闭条件下的深层地下水。     

中国中央造山带资源环境态势与可持续发展对策

资源与环境是谋求发展的物质基础和重要前提,其合理开发利用是实现可持续发展的重要内容。中国中央造山带富能、富矿、少植被、土地瘠薄,这对该区的经济发展既显示了无穷的诱惑,却又制约着对其的开发利用。对此,从保护利用水土资源、利用资源优势促进经济发展以及发展科技教育与提高人口素质三方面提出建议以促进该区走上可持续发展之路。     

The influence of volcanism on paleoclimate in the northeast of China： Insights from Jinchuan peat, Jilin Province, China

Just like contemporary sediments, peat itself is a good repository of information about climate change, the effects of volcanic activity on climate change have been truly recorded in peat, since it is a major archive of volcanic eruption incidents. A section of sand was identified as tephra from the Jinchuan peat, Jilin Province, China, for the grains look like slag with surface bubbles and pits, characterized by high porosity, and loose structure with irregular edges and corners. According to the peat characteristics of uniform deposition, the tephra was dated at 2002–1976 a B.P. by way of linear interpolation, so the time of volcanic eruption was 15 B.C.–26 A.D. (the calibrated age). While the geochemical characteristics of tephra in this study are quite the same as those of tephra from the Jinlongdingzi volcano at Longgang and from alkaline basaltic magma, with the contents of SiO₂<55%, and the similar contents to Al₂O₃ and Fe, but the contents of Na₂O>K₂O. We speculated that the tephra in this study came from the Longgang volcano group. Compared with 11 recorded volcanic eruption events as shown on the carbon and oxygen isotope curves of the Jinchuan peat cellulose, it is obviously seen that adjacent or large-scale volcanic eruptions are precisely corresponding to the minimum temperature and humidity. It seems that these volcanic eruptions indeed affected the local climate, leading to the drop of regional temperature and humidity. As a result, there was prevailing a cold and dry climate there, and all these changes can be well recorded in peat. So the comparison of volcanic eruption events with information about climate change developed from peat, can provide strong evidence for the impact of volcanism on climate change.     

Hydrogeochemical Characteristics of Shennongjia Forest District at Songbai Town, Hubei

1IntroductionSongbaiTown—thecapitaloftheShengnongjiaforestdistrictisthecenteroflocalpolitics,eco nomicsandculture ,anditisalsoanimportanttourismbase.Butinrecentyears,thelocalinhabi tantsinthisareahavesufferedfromcalculusdiseaseoccasionallyandthediseaseseemstobeofmoreandmorefrequentoccurrence .Thisnotonlycausesmasspanicandinfluencesnormalworkandstudyofthelocalpeople ,butalsobringsaboutnegativeeffectsontouristindustryofthisareaandrestrictsthedevelopmentoflocaleconomy .Inordertounderstandthesta…     

1995-2012年中国突发性环境污染事件时空演化特征及影响因素

利用ESDA空间统计分析方法和Matlab空间面板计量模型,对1995-2012年中国各地区发生的环境污染事件的时空演化特征和影响因素进行分析。结果表明:环境污染事件呈先动态增长后逐渐下降的趋势,水污染和大气污染事件是主要事故类型;环境污染事件发生的高频风险区域亦在逐渐减少,东南沿海及四川、湖南等中西部区仍有局部集聚的态势;1995-2000年中国的环境污染事件总体呈随机分布状态,2001年后则开始呈现集聚的特征;Moran散点图表明,局部的空间集聚先增强后减弱,环境污染事件近年来集中在泛长三角地区,高高地区为江浙沪;环境污染事件的重心转移方向主要为西南和东北,两个快速转移时期分别为1998-2001和2004-2007年,这与区域的产业转移和高负荷的污染排放压力有关;环境污染事件的发生与污染物的达标排放和控制、经济发展阶段及环境治理投入、环境监管能力、空间效应等因素有关。空间效应主要体现在空间邻近效应和空间溢出效应。未来应注重环境污染事故的区域联防联控,制定若干跨界污染事故的应急响应联动机制及环境污染区域联防联控机制。     

中国南方红土环境磁学

第四纪红土是中国南方古环境演化与气候变迁的最佳载体之一,记录了南方的古地理、古气候环境变迁信息.典型红土剖面由现代红壤层、均质层、网纹层、砾石层或基岩层组成,均质红土磁化率值多在80×10-8～250×10-8 m3/kg,网纹红土磁化率约低一个数量级.红土的磁化率-温度(χ-T)曲线、等温剩磁获得曲线、XRD和TEM分析认为,成土过程产生的细粒磁性矿物(包括磁铁矿、磁赤铁矿和赤铁矿)是红土磁性的主要载体.对红土的岩石磁学和矿物学综合分析认为,红土磁性矿物的含量、粒度、类型等可能指示其形成时期的某种环境变化,红土磁性是南方第四纪环境变迁研究的重要手段,但由于红土的物源以及受后期化学风化改造的复杂性,红土的环境磁学研究需要新的思路和方法.     

Humification degree of peat and its implications for Holocene climate change in Hani peatland, Northeast China

The humification degree of peat is a significant climatic proxy for paleoclimate change.Using the alkali-extraction method,a time series of absorbance values of the Hani peatland,Northeast China,was determined,which is used as an indicator for the humification degree of peat.Combined with14C dating data of peat cellulose,and compared withδ18O andδ13C time series of the cellulose in the Hani peatland,the evidence for the existence of14 ka paleoclimate was provided.Higher humification degrees hint a warmer-wetter climate,and vice versa.It also reconstructs the four stages of Holocene climate evolution in this region:11.5–9.8 cal ka B.P.,warm and wet period;9.8–9.0 cal ka B.P.,cold and dry period;9.0–4.8 cal ka B.P.,warm and wet period;and 4.8–0 cal ka B.P.,warm-wet and dry-cold alternation period.Meanwhile,it is revealed that the abrupt climate shifts signals such as the "8.2 ka" event and the "4.2 ka" event.Results showed that the Hani peat humification degree is of sensitive response to paleoclimate change.Therefore,it is a feasible method to analyze the relationship between paleoclimate change and peat humification degree.     

Application of 3S techniques in the assessment of eco-environmental impact of the Shennongjia ski field, Hubei Province, China

1 Background of the project and research route 1.1 Background of the project The Niuchangpin ski field at Shennongjia is designed as the biggest natural ski field in the Huazhong (central China) area, which will be a multifunctional ski field base incl…     

应用矿物磁测技术和X射线衍射研究氧化土中的磁性矿物

应用矿物磁测、Ｘ射线衍射和化学分析对氧化土的磁性矿物进行了研究。结果表明矿物磁测及磁分离技术与Ｘ射线衍射结合是鉴别土壤中磁性矿物的类型及其晶粒特征的有效方法,证明氧化土中的主要氧化铁矿物是赤铁矿和磁赤铁矿,针铁矿次之,磁铁矿偶见,其磁赤铁矿的含量可达１．６２％￣１．９２％。土壤中磁性矿物的晶粒特征多以超顺磁性和稳定单畴态存在,认为磁性矿物的成因是通过缓慢的成土化学作用产生的。