鹿井铀矿床铀矿物学特征

鹿井矿床位于南华活动带华夏褶皱带武功—诸广断隆区,闽、赣后加里东褶皱地块西缘,诸广山复式岩体中段,受遂川断裂及热水断裂组成的地堑式断陷带控制。本文主要对鹿井矿床内铀矿物的赋存状态、成分特征及组合特征进行了研究。     

河南干旱年地面雨滴谱特征

采用PMS公司生产的GBPP-100型地面雨滴谱仪，对河南省唐河地区17次降水过程进行了连续观测，其中层状云降水14次，积云降水3次。17次降水量都很小，5次有降水而无量，8、9月总降水量分别为8.3mm和31.3mm，占常年降水量的15.6%，属特别干旱的季节，该文利用观测获得的13928个样本，分析了干旱年降水的微结构特征。     

黑龙江省气候变化趋势对小麦产量的影响

利用黑龙江省1961～2003年逐日气象资料,采用世界粮食研究模型(WOFOST)和气候变化趋势分析的数学方法,分析了气候变化趋势对小麦产量变化趋势的影响.在黑龙江省中部、东部和北部相对湿润的小麦种植区域,辐射量降低趋势是小麦模拟产量降低趋势的主要气候原因;在松嫩平原西南部的齐齐哈尔市、大庆市和哈尔滨市,降水量增加的趋势是小麦模拟产量增加趋势的主要气候原因;在西北部的北安、五大连池、克山和克东4县,辐射量增加趋势是小麦模拟产量增加趋势的主要气候原因;黑龙江省小麦模拟产量变化趋势百分率的平均值为-1.57%/10a.     

机载LiDAR生成亚热带森林林下DTM的地面误差分析

目前LiDAR技术已经成为DTM的主要生产方法。地面误差对LiDAR生成DTM的精度影响比较明显,特别是由于亚热带森林植被覆盖区LiDAR激光点云少,生成的DTM更复杂,需要分析地面误差对LiDAR生成林下DTM的精度影响。本文以华南农业大学增城教学科研基地为研究对象,从森林郁闭度和坡度两个方面探讨了地面误差对机载LiDAR数据生成林下DTM精度的影响。研究结果发现高程误差会随郁闭度的增大而增大;而随坡度变化趋势不明显,但是坡度为15°时成为误差的分水岭,其前后误差差异比较明显。总体而言,郁闭度的影响更为明显。     

湘赣边界鹿井铀矿床流体包裹体及成矿机制

位于南岭成矿带南西部的鹿井矿床是华南热液型铀矿的典型代表.为查明其成矿流体来源、性质与演化以及成矿机制,开展了不同成矿阶段石英、萤石及方解石中流体包裹体的显微测温和不同阶段石英的氢?氧同位素分析.矿床地质特征表明成矿过程可划分为(I)粗晶石英+黄铁矿±绿泥石±绢云母、(II)沥青铀矿+硫化物+绿泥石+绢云母+暗灰色微晶...     

环境规制视角下城市绿色创新时空演变及溢出效应

基于2005—2019年中国266个地级及以上城市的面板数据,采用SBM-DEA模型评价城市绿色创新水平,刻画城市绿色创新的空间演变格局,最后构建空间杜宾模型实证分析不同类型的环境规制视角下城市绿色创新的溢出效应。研究结果显示：(1)时序发展上,研究期内城市绿色创新呈现东部地区、中部地区、西部地区、东北地区依次减弱的态势,总体上表现为“双M”型波动上升趋势,未来具有较大的增长潜力;(2)空间演化上,城市绿色创新在空间分布格局上存在明显的区域异质性,整体表现为东部地区主导发展的特征;(3)城市绿色创新在正式环境规制视角下存在正向溢出效应,在非正式环境规制视角下未产生显著溢出效应。     

高密度电阻率法三种不同装置应用效果对比研究

高密度电阻率法作为一种阵列式电法勘探方法,通过改变供电、观测电极的排列方式,可实现多种排列装置进行数据采集的功能,具有低成本、高效率的特点,已广泛应用于环境地质、工程地质和矿产地质等领域。为探究在不同地质背景、勘探目标时,各排列装置应用效果的特点,本文选取温纳、偶极—偶极和施伦贝谢尔(剖面)三种装置,对其在水库坝体渗漏检测和地下水勘查中的应用效果进行对比,研究各排列装置的特点。结果表明,温纳装置在勘探深度方面有明显的优势,纵向分辨率高,施工效率高,数据拟合效果好,信噪比高,抗干扰能强;偶极—偶极装置横向分辨率高,水平方向异常更细化,施工效率较高;施伦贝谢尔(剖面)装置具有较高的横向与纵向分辨率,采集数据点多,获取地电断面信息更丰富,抗干扰能力较强,勘探深度较深,数据拟合效果较好。综合对比研究认为,施伦贝谢尔(剖面)装置适宜在水库坝体渗漏检测中推广使用;温纳装置具适宜在勘探第四系潜水含水层中推广使用。     

Using autologistic spatial models to simulate the distribution of land-use patterns in Zhangjiajie, Hunan Province

Nowadays, spatial simulation on land use patterns is one of the key contents of LUCC. Modeling is an important tool for simulating land use patterns due to its ability to integrate measurements of changes in land cover and the associated drivers. The conventional regression model can only analyze the correlation between land use types and driving factors, but cannot depict the spatial autocorrelation characteristics. Land uses in Yongding County, which is located in the typical karst mountain areas in northwestern Hunan province, were investigated by means of modeling the spatial autocorrelation of land use types with the purpose of deriving better spatial land use patterns on the basis of terrain characteristics and infrastructural conditions. Through incorporating components describing the spatial autocorrelation into a conventional logistic model, we constructed a regression model (Autologistic model), and used this model to simulate and analyze the spatial land use patterns in Yongding County. According to the comparison with the conventional logistic model without considering the spatial autocorrelation, this model showed better goodness and higher accuracy of fitting. The distribution of arable land, wood land, built-up land and unused land yielded areas under the ROC curves (AUC) was improved to 0.893, 0.940, 0.907 and 0.863 respectively with the autologistic model. It is argued that the improved model based on autologistic method was reasonable to a certain extent. Meanwhile, these analysis results could provide valuable information for modeling future land use change scenarios with actual conditions of local and regional land use, and the probability maps of land use types obtained from this study could also support government decision-making on land use management for Yongding County and other similar areas.     

Nutrient compositions of cultured Skeletonema costatum,Chaetoceros curvisetus,and Thalassiosira nordenskildii

We cultured different-sized fractions of dominant phytoplankton species,Skeletonema costatum,Chaetoceros curvisetus,and Thalassiosira nordenski ldii,collected in different sea areas in various seasons,and measured and compared their C,N,P,Si contents.The N content of these species is similar,while the C,P,and Si contents of S.costatum from eutrophic Changjiang (Yangtze River) estuary are higher than those from Jiaozhou Bay (JZB),particularly the content of Si.The C,N,P,and Si contents of cultured phytoplank...