Late Cretaceous paleoclimate and paleoenvironment in the Songliao Basin,China

Journal of Paleolimnology - The Songliao Basin, northeast China, possesses an excellent Cretaceous lake sediment record that provides an opportunity to investigate Cretaceous terrestrial climate...     

Spatial Association Between Orogenic Gold Mineralization and Structures Revealed by 3D Prospectivity Modeling: A Case Study of the Xiadian Gold Deposit,Jiaodong Peninsula,China

Natural Resources Research - The Xiadian orogenic deposit with?~?100 t of gold resources, located in the Jiaodong Peninsula, Eastern China, shows an economically attractive gold...     

探讨基于PBL项目式学习的初中生地理综合思维素养培养——以人教版"影响气候的主要因素"为例

项目式学习注重学生对现实问题的主动探究,有利于培养初中生的地理综合思维素养。本文以“影响气候的主要因素”一课为例进行项目式学习,从创设任务情境、设计驱动性问题、运用可视化工具到优化评价方式等方面,提出了基于PBL模式的初中生地理综合思维素养培养的若干策略。     

欠发达农区家庭贫困的动态转变分析——以河南省为例

精准扶贫战略实施以来,以收入标准衡量的农村贫困人口大幅下降,但贫困具有多维性、动态性的特点,开展农户贫困动态变化研究对新时期农村贫困的有效治理具有重要的指导意义。论文基于2010—2018年河南农村固定观察点数据,从收入、生活条件、教育3个维度构建农户多维贫困评价指标体系,并运用马尔科夫概率转移矩阵和面板Logit模型对贫困状态类型转移及家庭陷入贫困的影响因素进行实证分析。结果表明：① 多维贫困比单维贫困(尤其是收入贫困)更能准确反映农区贫困状况;② 2010—2018年间,单维贫困发生率与多维贫困发生率之间差距不断扩大,这很大程度与教育贫困发生率大幅上升,而生活条件贫困、收入教育贫困和三维贫困明显下降有关;③ 单维贫困家庭更易转入教育贫困,多维贫困家庭更容易转入教育生活条件贫困;④ 农户贫困的发生是户主特征、家庭特征和村庄特征共同作用的结果,但不同类型贫困发生的影响因素有显著差异。与单维贫困发生相比,多维贫困发生受到更少因素的显著影响,并且各影响因素的作用更大。上述结论意味着新时期扶贫工作重点转向多维贫困的同时,应依据贫困类型制定具体扶贫措施,尤其重视教育等公共服务的供给。     

居住区典型地物热环境的日变化及其相互影响分析

居住区热环境状况是影响局地微气候变化的重要因素,研究居住区地物的热环境特征,对于了解和改善微气候具有重要意义。为了更好地揭示居住区热环境特征,本研究使用热红外成像仪对北京市某校园居住区进行观测,获取了夏季不同天气状况下（晴天、阴天、多云）的24 h热红外影像数据。依据各天气数据和地物属性,系统分析了各地物日变化规律,并通过垂线法判定邻近地物的温度边界范围,进而揭示出地物间温度交互特征。结果如下：① 太阳辐射是影响地物白天温度变化的主要因素,与地物温度呈正相关性;在多云天气下,地物的最高温度滞后至16:00出现,且地物温度曲线呈现连续的“锯齿状”升降趋势,云层的大量运动是导致多云天气下的地物温度波动变化的关键因素;沥青道路在夜间的温度均高于其他地物,并且夜间持续放热,提生周围环境温度;阴影能够有效减少地物吸收的太阳辐射量,降低地物表面温度;植被的冠层厚度与地物温度呈负相关性,因此增加居住区内绿植的冠层厚度,增大区域阴影面积有助于改善局地微气候;② 树木和裸土在06:00和14:00的温度交互作用强烈,表明在地物交界处,全天持续发生显著的热量交换;而夜间至凌晨,草坪与人行道持续进行热量交换,帮助降低路面温度,缓解周围高温状况。     

深度学习预测GPS时间序列在探索门源MS6.4地震前兆中的应用

以2016-01-21门源M_S6.4地震为例,提出用深度学习预测的GPS时间序列研究地震前兆。用震中附近门源台（QHME）、民乐台（GSML）及古浪台（GSGL）无震时的GPS时间序列训练LSTM神经网络,得到高精度的GPS时间序列预测模型,再分别对该地区无震时和地震前一段时间的GPS时间序列进行回溯性预测。对比预测时间序列与真实时间序列发现,震前2条时间序列大部分的相似性指标比无震时低,说明震前预测时间序列与真实时间序列差异明显,同时考虑震前时间序列的趋势异常,认为出现了异常时段;3个台站分别在E、N、U方向出现多个异常日期,且不同台站具有相同的异常日期,说明探索到了地震前兆。     

Impact of Phenanthrene on Denitrification Activity and Transcription of Related Functional Genes in Estuarine and Marine Sediments

The effects of phenanthrene(Phe)on the denitrification activity and denitrifying genes(narG,nirS and nosZ)were evaluated by dose-response experiments in sediments of Dagu River Estuary(DRE)and Jiaozhou Bay(JZB).The results showed that potential denitrification activity(PDA),N2O,NO3−and NO2−reduction rates of both areas were inhibited with an increase of Phe concentrations.The PDA,N2O,NO3−and NO2−reduction rates of both areas was highest and lowest in the control(DRE:0.453,0.427,7.439 and 3.222mgNkg−1 h−1,JZB:0.592,0.555,8.470 and 3.793mgNkg−1 h−1)and highest Phe amended treatments(DRE:0.069,0.001,4.486,and 1.563 mgNkg−1 h−1;JZB:0.114,0.024,5.527 and 2.200 mgNkg−1 h−1).The inhibition rate of PDA was highest,follow by NO2−reduction and then NO3−reduction.Moreover,with the increasing of Phe concentrations,total bacteria count and the abundance of denitrifying genes were decreased.And N2O accumulation was promoted with the addition of Phe for both areas.Based on the comparison of EC50 values,denitrifiers harboring three genes were more sensitive to Phe than PDA,and denitrifiers harboring nirS gene were more sensitive,followed by nosZ gene,and then narG gene.Furthermore,according to correlation analysis,the relative abundance of denitrifying genes was much more positively correlated with PDA,NO3−and NO2−reduction than total bacteria count.In addition,the denitrification activity and total bacteria count in JZB were more inhibited than that of DRE.This study is useful for understanding the impact of Phe pollution on denitrification in estuary and marine sediments,with profound implications for the management of aquatic ecosystems regarding eutrophication(N-removal)and greenhouse effect.     

Quality Assessment of Frozen Solenocera crassicornis Treated with Sodium Metabisulphite by Soaking or Spraying

The present work was carried out to evaluate the safety of shrimp(Solenocera crassicornis)treated with different concentrations of sodium metabisulfite(SMB)by soaking or spraying during frozen storage.Shrimps soaked in higher concentrations of SMB showed higher sensory scores,lower total color differences,and better anti-melanosis effects than shrimps in the control and other treatment groups throughout frozen storage(−18℃).Lower total volatile basic nitrogen and thiobarbituric acid reactive substances and higher salt soluble protein contents were detected in shrimp soaked with high doses of SMB compared with other samples.In addition,lower counts of total aerobic plates and psychrotrophic bacteria were observed in shrimp treated by soaking with higher doses of SMB than those in control shrimp and shrimp treated with other methods during frozen storage(−18℃).However,the SO2 content of 5%SMB-soaked samples exceeded the maximum allowable limit of 100mgkg−1.Overall,the use of 1.5%SMB soaking to treat shrimp results in good antioxidant and antimicrobial effects and,thus,may be suggested to preserve S.crassicornis under frozen conditions.The results of this study present important guidance on the use of SMB to maintain the quality of marine-trawling shrimp from manufacturing to consumption.     

浅议智慧城市时空大数据平台的建设——以临沂市为例

自智慧地球概念提出后,世界各国给予广泛关注,国内也先后启动了智慧城市建设相关计划。经原国家测绘地理信息局批准,作为智慧临沂建设重要组成部分的智慧临沂时空信息云平台建设也正式启动。该文介绍了智慧城市时空大数据平台建设的必要性及国内外智慧城市时空大数据平台建设的典型结构,阐述了智慧临沂时空信息云平台的主要建设内容,包括时空基准、时空信息大数据中心、时空信息云平台、云支撑环境、智慧应用等方面,并对智慧临沂建设的成果和下一步工作重点进行了总结和展望,为临沂市智慧城市应用打下基础,并为全国智慧城市的建设积累宝贵经验。