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1.
以成都市为研究对象,围绕不透水面与生态环境质量的时空变化规律展开研究,并探讨两者间的关系。以2000年、2009年和2018年的遥感卫星影像为基础数据,利用归一化不透水面指数提取不透水面信息,通过主成分分析构建遥感生态指数(RSEI)评估成都市近20年间的生态环境质量,最后运用回归模型定量分析不透水面覆盖度与生态环境的关系。结果表明:2000-2018年成都市不透水面增加了1 072 km~2,RSEI均值由0. 603下降到0. 504,降幅为16%,RSEI空间变化格局与不透水面扩张格局基本一致;回归模型发现不透水面覆盖度与地表温度为指数函数关系,与植被指数呈线性负相关;多元逐步回归分析证明植被、地表温度和不透水面均是影响城市生态环境质量的重要因素,而不透水面信息起到了决定性作用。  相似文献   

2.
基于福州城区两时相 Landsat 影像,根据城市发展程度差异将研究区划分为 Zone 1、 Zone 2、Zone 3三个环形区域,在反演地表温度和获取不透水面覆盖度信息的基础上,计算各区域 各级不透水面覆盖度的热分布指数和热效应贡献度指数,分析2004—2021年福州市不同发展程度 区不透水面覆盖度与地表温度之间的定量关系,并运用地理探测器分析植被覆盖度、不透水面覆 盖度和海拔高度对地表温度(Land Surface Temperature,LST)空间异质性的影响。结果表明:2004— 2021年,Zone 1不透水面扩张较少,Zone 2和Zone 3不透水面扩张明显,增加最明显的为Zone 3内 不透水面覆盖度大于60%的区域;不透水面覆盖度大于60%的区域对城市高温面积贡献最大,不 透水面覆盖度为80% ~ 100%时热效应贡献度最大;2004年影响地表温度的主导因子为植被覆盖 度,2021年Zone 1中不透水面覆盖度为影响地表温度的主导因子,其余区域中海拔高度为影响地 表温度的主导因子;福州市地表温度空间分异受多因子共同影响且两因子交互q值均高于单因子q 值。研究结果可为城市规划和缓解城市热岛效应提供参考。  相似文献   

3.
通过分析南昌市不透水面和城市热岛的相关关系从而为缓解城市热岛效应提供技术指导.以南昌市2002年、2014年Landsat TM/TIRS遥感影像作为数据源.采用改进的归一化水体指数(modified normalized difference water index,MNDWI)进行水体的提取,结合归一化差值不透水面指数法(normalized difference impervious surface index,NDISI)对南昌市不透水面信息进行提取,然后采用单窗算法进行温度反演.分析比较2个时期的不透水面分布图和地表温度分布图,在2002-2014年间,南昌市不透水面面积与高温分布面积都明显增加,且主要是沿赣江两岸扩张.而从二者的线性回归方程式中可以看到,它们之间存在着显著的正相关性,这说明城市不透水面面积的增加会加剧城市热岛效应.  相似文献   

4.
基于Landsat影像,利用全约束最小二乘法混合像元分解的方法,获取福州中心城区不透水面覆盖度信息,利用同期高分辨率影像面积对比法验证分解结果。根据不透水面覆盖度大小进行分级以表示城市发展程度,采用亚像元状态转移矩阵分析2000年至2016年各等级不透水面区域面积的变化,利用景观指数对城市不同发展程度区域斑块分布变化情况进行分析。结合地表温度归一化方法,计算各级不透水面区域的温度贡献率,并对比城市不同发展程度区域分布对城市热岛效应的影响。结果表明,福州城市化进程主要集中于不透水面覆盖度在30%~60%的区域内,城市发展程度不同的区域相互参杂分布于中心城区内;不透水面覆盖度大于50%的区域促进城市热岛效应的产生,随着斑块破碎化程度的增加,加剧热岛效应产生。研究结果可为缓解城市发展过程中的热岛效应提供参考。  相似文献   

5.
玉溪市区为例,以Landsat 8卫星遥感影像为数据源,将定量遥感分析中的线性光谱分解技术用于提取不透水面信息,并利用土壤调节植被指数和大气校正法分别提取出植被、地表温度等要素信息,并分析他们的相关关系.实验分析表明,越靠近玉溪城市中心区域,不透水面盖度值越大;不透水面信息与植被要素呈现较为显著的负相关关系,相关系数为0.866 5;而不透水面与地表温度信息存在明显的线性正相关关系,相关系数达到0.859 8.  相似文献   

6.
以郑州市为例,基于多期Landsat遥感影像和夜间灯光数据分析了城市地表温度、不透水面、植被以及城市人口的时空变化特征,并从不透水面、植被和人口密度三个方面分析其对城市地表温度的影响.结果表明:郑州市明显存在地表温度中心城区高,郊区低的热岛效应,热岛斑块逐渐向东南部、西部和北部扩散且逐渐破碎化,热岛面积呈增长趋势;不透水面指数与地表温度呈显著的指数正相关关系,植被指数、人口密度与地表温度分别呈现出较显著的线性负相关和正相关关系.利用逐步回归的方法表明,不透水面是影响城市地表温度的主要原因,植被和人口密度也是影响城市地表温度的重要因素.  相似文献   

7.
城市空间的快速扩展使得大量的不透水面取代了以植被为主的自然地表景观,对城市生态系统造成了明显的负面影响.福州市经过近30年的城市扩展,城市建成区中的不透水面大幅增加,植被急剧减少,城市生态发生了明显变化,其中最显著的就是严重的城市热岛效应.为此,基于Landsat系列遥感影像获得福州1989和2014年2个时相影像的不透水面、水体、植被和地表温度信息,运用多元回归模型定量分析了1989~2014年间福州城市不透水面的时空变化对城市热环境产生的影响.结果表明:(1)1989~2014年间,研究区不透水面净增了87. 16km~2,增加了161%;(2)不透水面和地表温度呈指数函数关系,高不透水面比例地区升温明显快于低不透水面比例地区;(3)1989~2014年间增加的87. 16km~2不透水面及相应减少的70. 09km~2和14. 92km~2的植被和水体对研究区地表温度上升的综合贡献达16. 54℃.  相似文献   

8.
热岛效应是典型的城市气候现象,它的形成及强度与土地利用类型、景观格局等诸多因素有关.本文基于深圳市2010年遥感影像,采用线性光谱混合模型提取土地利用/覆盖等信息,利用最小二乘法和地理加权回归方法分别分析城市景观格局对地表温度的影响.结果表明:深圳市地表温度介于22.28~41.34℃之间,从西北到东南逐渐降低,城市不透水面温度显著高于植被覆盖区域,城市热岛效应明显.地理加权回归模型可以有效处理回归分析中空间非平稳性现象,能更好地刻画景观格局与地表温度之间的定量关系.植被格局指数对地表温度的空间分布解释率较高,其中归一化植被指数(NDVI)、叶面积指数(LAI)对地表温度的解释率最高,分别达88%、90%.不透水面面积、破碎度、邻近度,植被优势种种类、密度、空间分布以及垂直水平生长情况等共同影响深圳市的地表温度.在城市建设实践中,避免不透水面连片集中,降低其邻近度,同时尽可能增加城市的绿地面积,提高NDVI和LAI数值,是缓解城市热岛效应的有效手段.  相似文献   

9.
目前城市不透水面信息提取的研究主要基于光学遥感影像提取.但使用光学遥感手段提取不透水面信息易受到云层遮挡及光谱混淆等问题的影响.为此,提出了一种新的基于InSAR技术的图像分类方法.通过对Sentinel-1影像进行干涉分析,计算出各地物的后向散射特性中的相干系数值,然后建立随机森林并利用回归分析法获取不透水面的相干系...  相似文献   

10.
基于北京市2000年增强型专题制图仪和2010年专题绘图仪遥感影像,利用线性光谱混合分析模型对两幅影像实施亚像元分解,获取城市不透水面的空间较为精确的分布情况。在此基础上,结合研究区土地利用和实地资料,利用归一化建筑指数与混合光谱分析的方法,对北京市近10年来不透水面动态变化格局进行分析,研究城区不透水面的变化情况。研究结果表明:基于混合像元分析的不透水面变化信息提取方法是行之有效的。10年间北京五环内不透水面覆盖度总体上随着城市化进程呈现放射状扩张,城市建设是形成不透水面的重要驱动力之一。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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