城市规划中的GIS应用分析

分析了GIS技术在城市规划中的应用现状,介绍了GIS技术在城市规划设计与管理各方面的具体应用情况,对GIS技术在城市规划中的应用前景作了展望.     

等高线空间关系研究

地形图上等高线相互之间的空间关系是人们分析地形的重要依据,也是利用GIS模拟地形图认知能力的一个重要出发点在利用计算机模拟人们判读地形图的过程中面临的一个关键问题是：如何在计算机环境下有效地描述、表达及计算等高线空间关系,本文从空间认知的需求出发,在等高线空间关系分类的基础上,利用图论中的树结构(等高线树)形式化表达等高线空间关系,在Voronoi邻近的基础上建立了计算机可执行的等高线空间关系计算方法。     

基于Sentinel-1数据对青藏高原五道梁多年冻土区地面形变的监测与分析

在气候变暖背景下,地面形变监测可以反映多年冻土的发育趋势。利用欧空局Sentinel-1降轨数据（2014年11月27日至2017年3月4日）,基于SBAS-InSAR技术,获取了五道梁多年冻土区的地面形变状况,并分析了环境因子对其的影响。结果表明,近年来该地区地面主要表现为沉降趋势,与水准实测形变趋势吻合,相对误差为22.4%,均方根误差为4.3 mm;形变变化速率为-10.28 mm·a^-1,相对误差为14.79%。植被类型、地形地貌对多年冻土区地面形变影响较大。植被发育越好,由于土壤含水量越高,地面形变量越大;而植被覆盖度在一定程度上会影响Sentinel-1数据获取地面形变信息的精度;地形起伏较大的山区形变量存在垂直向与南北向的差异;水体分布较多的地区,信号失相干相对严重,Sentinel-1数据获取地面形变信息的能力会受到较大的影响。此外,降水事件与日冻融循环作用对Sentinel-1数据获取地面形变信息的精度影响也不可忽略。因此,在利用Sentinl-1数据获取青藏高原多年冻土区地面形变信息时,要综合考虑下垫面、气候条件与冻土日冻融循环的影响。     

黔北习水县桑木场铅锌矿岩相学、矿相学特征 及与MVT型铅锌矿床的对比

习水县桑木场铅锌矿,容矿层为震旦系灯影组白云岩,属于局限台地相的碳酸盐盆地;铅锌矿受断层与裂隙控制,属于开放式空隙充填,矿石与容矿层呈脉状、网脉状接触。矿石矿物为闪锌矿及方铅矿,脉石矿物为重晶石、方解石、白云石、萤石、黄铁矿及石英。样品表现出两期成矿特征,根据矿物穿插关系可判定与流体活动相关的矿物生成顺序。本文结合习水县桑木场区域地质特征及样品岩相学、矿相学特征,初步判定研究区铅锌矿属于密西西比河谷型(MVT)铅锌矿,并以此典型矿床的成矿模式为指导,尝试在研究区内寻找较大型铅锌矿床。     

贫碱结构水类型祖母绿红外光谱特征及其控制因素探究

祖母绿红外吸收主要与其硅氧骨干、通道内结构水、相关碱性金属离子和大分子振动有关。国内外相关研究主要集中在峰位归属及谱峰特征对比方面,认为与分子振动和不同类型结构水相关,对更深层的成矿或化学控制因素的研究还较少。本文选取典型4个矿区样品,针对贫碱结构水(Ⅰ型)特征为主的祖母绿进行了近、中红外光谱测定,在此基础上初步探讨其主要控制因素。结果表明:同为Ⅰ型水主控的不同矿区祖母绿呈现一致特征,若干与结构水、碱性离子及大分子相关吸收具有稳定峰位、近似的相对峰强和峰形的特征。分析发现:祖母绿红外谱带特征直接受控于通道中结构水的占位方向和比例,进一步与祖母绿成矿元素Al~(3+)的类质同象替换相关,主要受(Mg~(2+)+Fe~(2+))离子浓度影响,当其浓度较低时,类质同象替换程度较低,祖母绿结构水占位主要表现为Ⅰ型水特征,其相关元素特征表现为高Si、Al,低Mg、Fe,总体贫碱,对应相应的典型红外特征,指示化学离子浓度与红外谱学特征之间的关系。研究过程表明红外光谱可以辅助对Ⅰ型水祖母绿产地的鉴定和成矿环境的认知。     

Medicinal Plants Harvesting in Wolong National Nature Reserve

A combination of sample surveys and questionnaires were used to investigate the harvesting of wild medicinal plants (WMP) in Wolong National Nature Reserve (WNNR) from August 2014 to July 2015. These surveys showed that up to 20 families and 45 species of WMP were harvested in WNNR. Gastrodia elata, Paris polyphylla, Fritillaria thun-bergli, Rheum officinale, Rhodiola rosea, Saussurea medusa, Notopterygium root, Radix Ginseng, Buddha’s palm were harvested intensely. The harvesting, which occurred mainly in autumn and winter (from June to October) in the test area, buffer area and core area, was located mostly in the residential and crop production areas of Wolong Town and Gengda Town, and in the timberline, alpine meadows and scree areas of Dengshenggou Ravine and Balangshan Mountain (specifically in Dengshenggou, Tangfang, Tizigou Ravine, Weijiagou Ravine and Reshuihe River areas). Among all the harvesters, 58% came from inside the WNNR, and 42% came from outside the WNNR; 87% were male, and 13% were female; 6% were under the age of 18, 69% were 19-45 years old, 19% were 46-65 years old, 6% were over 66 years old. The main purpose of harvesting was commercial sale to increase household income. Based on the analysis and discussion of the results, comprehensive management measures were introduced to strengthen the awareness and efficacy of laws and regulations, integrate the enforcement of these laws, establish and strengthen inspections. Skills training and the domestication of the wild medicinal materials were used to encourage the surplus labor force to avoid excessive harvesting and move into other agricultural endeavors.     

贵州独山下泥盆统碎屑岩物质特征与构造背景及物质来源讨论

本文通过Qt-F-L、Qm-F-Lt判别图与砂岩构造环境判别图对贵州独山地区下泥盆统丹林组、舒家坪组碎屑岩矿物成分、主量元素的综合分析研究。证明本研究区早泥盆世碎屑岩物源区大地构造背景为被动大陆边缘,并认为碎屑岩物源来自江南造山带与扬子克拉通。     

图解法与矩值法在金沙江上游雪隆囊古滑坡堰塞湖溃坝堆积物粒度分析中的应用

基于野外调查与室内分析,应用图解法和矩值法,分别对金沙江上游雪隆囊古滑坡堰塞湖溃坝堆积物的50个样品的粒度参数进行定量计算,并对两种方法所得结果进行对比研究。结果表明:溃坝堆积物的上、中、下游三个区段的两种计算结果的平均粒径具有高度相关性,相关系数分别为0948、0994、0991,分选性相关系数分别为0824、0959、0901,表明两种方法得到的平均粒径基本相等,可以互相代替;标准偏差（分选系数）除上游区段存在较大偏差外,其它两区段分选系数基本相等,可以相互替代。整个溃坝堆积物粒度的偏态和峰态较离散,相关性较差。针对溃坝型沉积物,建议优先选用矩值法计算粒度参数,该方法能全面涵盖样品信息,反映整个沉积过程中水动力条件的变化。该研究结果与其它类型沉积物研究结果产生差异的主要原因是粒度组分分布情况、沉积动力条件及沉积环境不同。     

Biomediated Precipitation of Calcium Carbonate in a Slightly Acidic Hot Spring, Yunnan Province

A slightly acidic hot spring named "Female Tower"(t=73.5°C, pH=6.64) is located in the Jifei Geothermal Field, Yunnan Province, southwestern China. The precipitates in the hot spring are composed of large amounts of calcite, aragonite and sulfur. Scanning electron microscopy(SEM) analyses reveal that the microbial mats were formed from various coccoid or rod-shaped filamentous microbes. Transmission electron microscopy(TEM) shows that the intracellular sulfur granules are commonly associated with these microbes. A culture-independent molecular phylogenetic analysis demonstrates that the majority of the bacteria in the spring are sulfur-oxidizing bacteria. In the spring water, H_2S concentration is up to 60 ppm, while SO_4~(2-) concentration is only about 10 ppm. We speculate that H_2S might derive from sulfur-oxidizing bacteria in this hot spring water, leading to the intracellular formation of sulfur granules. Meanwhile, this reaction increased the p H in the micronscale microdomains, which fosters the precipitation of calcium carbonate in the microbial mats. The results of this study indicate that the sulfur-oxidizing bacteria might play an important role in calcium carbonate precipitation in slightly acidic hot spring environments.