东太湖围网拆除前后水生植被群落遥感监测及变化

为削减东太湖养殖污染,改善湖泊水质,苏州市于2018年底基本完成东太湖养殖围网拆除工作.围网拆除后,湖泊生态环境对此如何响应,已成为学者及相关管理部门关注的重点.水生植被在维持湖泊生态系统平衡、物质循环和净化水质方面发挥着重要的作用,是诊断湖泊生态系统健康状态的关键指标.本研究基于Sentinel-2卫星数据,利用分类决策树模型和基于生活史的沉水植被优势种群提取方法,监测了东太湖2017年(围网拆除前)和2019年(围网拆除后)的水生植被类群和沉水植被优势种群的空间分布.经验证,水生植被类群监测精度为82.66%,Kappa系数为0.77;沉水植被优势种群的监测精度为62.08%,Kappa系数为0.56.结果表明:围网拆除后,东太湖水生植被优势类群由围网拆除前的沉水植被转变为浮叶植被;沉水植被分布面积减少,且种群由优势度相差不大的七大优势种群逐步向菹草和伊乐藻占据绝对优势发展,逐渐趋于单一化.     

地图投影变换接口技术

地图投影变换功能是GIS的基础功能,目前各种商用的GIS软件都具备地图投影变换功能,但其完整性、通用性、规范性以及可扩充性都有所不足.为了提高地图投影变换功能软件的通用性及可扩充性,对通用地图投影变换接口技术进行了深入研究,设计并实现了通用地图投影变换接口模块.通过实验测试,本接口模块可以很好地满足用户实际应用需求,具有一定的实用价值.     

福建政和县东际金（银）矿床黄铁矿微量元素和硫-铅同位素及锆石年龄研究

东际金(银)矿床赋存于燕山晚期南园组火山岩中,是东南沿海地区一个隐爆角砾岩型贵金属矿床,已探明金资源量达12.5 t,银资源量135.9 t。通过开展主要金属硫化物黄铁矿电子探针和硫-铅同位素分析,讨论了成矿作用和成矿物质来源等问题。研究表明,东际金(银)矿床黄铁矿Co/Ni值3～94(平均值23)且Co含量为500×10-6～1070×10-6(均值799×10-6),Fe/(S+As)值0.827～0.871(均值0.860),Au/Ag值0.9～5.5(均值2.6),反映该矿床是与陆相火山作用有关的浅成中低温热液型矿床。黄铁矿δ34S在-6.6‰～-0.7‰,206Pb/204Pb为17.9801～18.4303,207Pb/204Pb为15.2689～15.9397,208Pb/204Pb为37.9052～38.7871,指示成矿物质主要来源于具有壳幔混源性质的花岗质岩浆,此外含矿热液也活化萃取了部分基底变质岩和火山岩围岩的金属元素。通过锆石U-Pb年代学研究和区域成矿资料对比,东际金(银)矿床成矿时代可被限定于早白垩世晚期。     

伊通盆地莫里青断陷双阳组湖泊水下扇沉积特征

本文详细研究了伊通盆地莫里青断陷双阳组沉积类型,并将该区湖泊水下扇的岩相组成划分为5种类型：经典浊积岩相、块状砂岩相、砾质砂岩相、颗粒支撑砾岩相、基质支撑砾岩相;将湖泊水下扇划分为内扇、中扇、外扇三个亚相,对各亚相进一步划分了若干微相。湖泊水下扇沉积为该区地层的主要沉积特征,在垂向上具有进积型和退积型两种类型。     

以海藻为原料的对虾人工配合饵料粘合剂及其应用

Ⅰ. 材料和方法Ⅰ.1. 粘合剂和饵料加工 根据我国的实际情况,比较理想的粘合剂应该是粘合效果好、在海水中稳定性强、不影响对虾的摄食和生长、用量少、原料来源广、成本低和加工方法简单等。根据上述特点我们研制了以海藻为原料的对虾人工饵料粘合剂。     

鄂尔多斯盆地东南部黄龙背斜的构造几何学与运动学

研究克拉通内构造变形对于揭示克拉通的构造属性具有重要意义,对于油气勘探也具有重要的参考价值。本文应用钻井与高精度反射地震资料,剖析了鄂尔多斯盆地东南部黄龙背斜的构造几何学与运动学特征。研究表明,黄龙背斜发育在渭北隆起东端,是一长18 km、宽15 km的短轴状背斜,地层起伏幅度达200 ms;黄龙背斜自长城系往上至三叠系均具有相似的背斜形态;它是在燕山期基底断层复活而形成的断层传播褶皱背斜;黄龙背斜区内东西向与南北向剖面控制的缩短分别为70 m和90 m,缩短量较小,指示该部位处于燕山期冲断变形的前锋部位,变形即将终止。黄龙背斜响应于周缘构造边界挤压作用,是克拉通内部的基底正断层反转而在沉积盖层形成的褶皱背斜,因地层能干性差异发生了分层剪切。黄龙背斜是一个有利的天然气勘探目标。     

基于现场可编程门阵列的幸运成像算法的实现

幸运成像技术是用于消除天文图像中大气湍流影响的高分辨率图像重建技术,传统的基于中央处理器的幸运成像算法难于实时化。利用现场可编程门阵列并行处理的优势,设计了一种基于现场可编程门阵列的幸运成像算法并构建了一个实验系统。该系统用现场可编程门阵列完成了选图、配准、叠加的全部幸运成像算法流程,所得高分辨率图像与基于传统中央处理器算法处理的结果完全相同,但幸运成像算法的处理速度比传统中央处理器的处理速度快19倍。该算法在现场可编程门阵列上的实现,为幸运成像技术的实时或准实时化提供了一种可行的方案。     

近50a河池市日照时数空间变化特征分析

基于河池市10个气象站1961-2010年的日照时数数据,采用线性趋势分析、逐步回归分析等方法,依托GIS技术对河池市近50a日照时数的气候倾向率、年代际变化趋势进行分析。结果表明:河池南部及东南部的都安、宜州、巴马、大化县的年日照时数较多(大于1200h),北部及西北部的天峨、南丹、环江县的北部年日照时数较少(小于1000h);全市各地区的年日照时数变化速率值在-82.66 h/10a～19.8 h/10a之间;河池各县的日照时数年代际变化特征各不相同,其中东兰、凤山和都安大部地区的年日照时数的四个年代都是呈现下降的变化趋势。     

EVALUATION OF CORRECTIONS ON TURBULENT FLUXES OBTAINED BY EDDY COVARIANCE METHOD IN HIGH WINDS

This paper investigates processing of fast-response data and corrections of turbulent fluxes obtained by using eddy covariance method based on data collected at an offshore observation tower during three Cold-intrusion(CI)events in the South China Sea in 2010. This study presents the data processing procedure in detail and compares frictional velocities(u*), sensible heat fluxes(H) and latent heat fluxes(LE) yielded by using different averaging periods and different coordinate rotation methods; evaluates the sonic temperature correction for sensible heat flux and the Webb correction for latent heat flux as a function of 10 m wind speed(u10) during the CIs. The results show(1) that the different averaging periods of 30 min and 10 min cause biases of u*(H, LE) within 5%(15%, 62%). The values of u*(H,LE) averaged from 30 mins are mostly larger than those averaged from 10 mins. We suggest that the averaging period of 10 min is not sufficiently long to capture all scale eddies and recommend 30 min averaging period in calculating turbulent fluxes using eddy covariance method during CIs;(2) that the values of u*(H, LE) obtained from double rotation(DR2) and those obtained from planar fit rotation(PF) have good agreements and correlation coefficients between them are larger than 0.99. Because PF method requires unchanged environment and it is easier to apply DR2 method, we suggest DR2 coordinate rotation method in processing fast-response data; and(3) that the median values of frictional velocity(sensible heat flux and latent heat flux) binned according to 2 m s~(-1) intervals of u_(10) increase(decrease,increase) by less than 9%(4%, 10%) by Coriolis corrections(sonic temperature corrections, Webb corrections), which decreases(decreases, increases) with increasing u10 when u10 are 5-17 m s~(-1).     

通过数据挖掘调查气候变化的长期趋势及其因区域和地方环境而产生的空间差异（英文）

Climate change is a global phenomenon but is modified by regional and local environmental conditions.Moreover,climate change exhibits remarkable cyclical oscillations and disturbances,which often mask and distort the long-term trends of climate change we would like to identify.Inspired by recent advancements in data mining,we experimented with empirical mode decomposition(EMD) technique to extract long-term change trends from climate data.We applied GIS elevation model to construct 3 D EMD trend surface to visualize spatial variations of climate change over regions and biomes.We then computed various time-series similarity measures and plot them to examine spatial patterns across meteorological stations.We conducted a case study in Inner Mongolia based on daily records of precipitation and temperature at 45 meteorological stations from 1959 to 2010.The EMD curves effectively illustrated the long-term trends of climate change.The EMD 3 D surfaces revealed regional variations of climate change,while the EMD similarity plots disclosed cross-station deviations.In brief,the change trends of temperature were significantly different from those of precipitation.Noticeable regional patterns and local disturbances of the changes in both temperature and precipitation were identified.The trends of change were modified by regional and local topographies and land covers.