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用树轮灰度重建乌孙山北坡4-5月平均最低气温 被引量:26
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作者 张瑞波 袁玉江 +2 位作者 魏文寿 喻树龙 陈峰 《中国沙漠》 CSCD 北大核心 2008年第5期848-854,共7页
利用2006年采自新疆伊犁乌孙山北坡3个采点的树轮样本,建立了树轮宽度年表,采用树轮图像分析法进一步建立了3种宽度年表和5种灰度年表。相关分析发现,在所有参数年表中乌孙山北坡3个树轮标准化全轮灰度年表序列与该地区4—5月平均最... 利用2006年采自新疆伊犁乌孙山北坡3个采点的树轮样本,建立了树轮宽度年表,采用树轮图像分析法进一步建立了3种宽度年表和5种灰度年表。相关分析发现,在所有参数年表中乌孙山北坡3个树轮标准化全轮灰度年表序列与该地区4—5月平均最低气温显著相关,相关系数最大可达-0.552。经多方面检验可知,利用树轮标准化全轮灰度年表重建该地区过去324a的4—5月最低气温是可信的。通过对重建最低气温序列进行功率谱分析发现乌孙山北坡4—5月最低气温具有31a、36a和48a的变化准周期;小波分析证实,31~32a的低频变化周期最为显著,1800年以前,震荡随时间推移逐渐减弱,周期逐渐缩短,19世纪后期震荡加强,进入20世纪,震荡减弱,逐渐趋于稳定。4—5月平均最低气温经历了11高11低的变化阶段。 展开更多
关键词 乌孙山北坡 树木年轮 平均最低气温 小波分析
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祁连山西段党河南山北坡3个不同特征的金矿床研究 被引量:11
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作者 范俊杰 路彦明 +1 位作者 丛润祥 常春郊 《地质找矿论丛》 CAS CSCD 2008年第1期48-53,共6页
黑刺沟金矿床以富As和Sb的微细浸染蚀变岩型金矿化和部分石英脉型锑-金矿化为特征,典型矿物组合为黄铁矿-毒砂(辉锑矿)-石英;贾公台金矿床以少硫化物石英脉型金矿化和蚀变岩型金矿化为特征,As和Sb的质量分数不高,典型矿物组合为黄铁矿-... 黑刺沟金矿床以富As和Sb的微细浸染蚀变岩型金矿化和部分石英脉型锑-金矿化为特征,典型矿物组合为黄铁矿-毒砂(辉锑矿)-石英;贾公台金矿床以少硫化物石英脉型金矿化和蚀变岩型金矿化为特征,As和Sb的质量分数不高,典型矿物组合为黄铁矿-自然金(方铅矿)-石英-钾长石;鸡叫沟金矿床以蚀变岩型金矿化为主,次之为石英脉型金矿化,典型矿物组合为黄铁矿-黄铜矿-石英。3个金矿床的成因均与岩浆岩有密切联系,但各矿区的岩浆岩在岩石学、岩石化学、微量元素及稀土元素特征具有差异,表明其成因不尽相同。这可能是造成3个金矿床地质特征差异的主要原因。 展开更多
关键词 党河南山北坡 金矿床 地质特征 岩浆岩
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新疆伊犁乌孙山北坡树轮灰度年表的建立及气候意义 被引量:6
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作者 张瑞波 喻树龙 +1 位作者 袁玉江 魏文寿 《沙漠与绿洲气象》 2009年第1期14-19,共6页
利用2006年采自新疆伊犁乌孙山北坡3个采点的树轮样本,建立了树轮宽度年表,采用树轮图像分析法进一步建立了3种宽度年表和5种灰度年表。宽度年表对比发现,树木年轮对气候响应南疆强于北疆,北疆其它地方强于伊犁地区,而乌孙山北坡与伊犁... 利用2006年采自新疆伊犁乌孙山北坡3个采点的树轮样本,建立了树轮宽度年表,采用树轮图像分析法进一步建立了3种宽度年表和5种灰度年表。宽度年表对比发现,树木年轮对气候响应南疆强于北疆,北疆其它地方强于伊犁地区,而乌孙山北坡与伊犁其它地区比较,树轮宽度对气候的响应较敏感。树轮图像分析法建立的8种年表特征进行对比发现,恰依恰孜宽度年表对气候的响应最为强烈;而阿乌里亚乔克标准化灰度年表对气候的响应较好。相关分析表明,全轮灰度、早材灰度和最大灰度与4、5月气温相关较好。4月降水和实测宽度、全轮宽度以及早材宽度相关较好,而6月降水与全轮灰度和早材灰度相关较好。早材宽度对气候的响应强于晚材宽度;全轮灰度和早材灰度对气候的响应较好。利用树轮图像分析所得到的8个树轮参数年表可增加气候重建代用指标,提高气候重建的精度。 展开更多
关键词 乌孙山北坡 灰度年表 树木年轮 气候变化
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西天山北坡地区近50年来气温和降水变化分析 被引量:2
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作者 姚付龙 李海冰 《安徽农业科学》 CAS 2012年第9期5550-5553,5592,共5页
[目的]分析西天山北坡地区近50年来气温和降水的变化特征。[方法]根据西天山北坡地区3个气象站1961~2010年的气温、降水资料,利用线性趋势分析法及5年滑动平均等方法,分析了该地区50年来的气候变化。[结果]西天山北坡地区气温呈现明显... [目的]分析西天山北坡地区近50年来气温和降水的变化特征。[方法]根据西天山北坡地区3个气象站1961~2010年的气温、降水资料,利用线性趋势分析法及5年滑动平均等方法,分析了该地区50年来的气候变化。[结果]西天山北坡地区气温呈现明显增暖趋势,近50年的年均温以0.3℃/10a的速率显著升高,但各季节温度上升率不同,秋季〉冬季〉春季〉夏季。西天山北坡地区50年来的年降水量总体呈相对增多趋势,从年降水量来看,平均以16.9 mm/10a的速率明显增加;从季节降水量来看,除秋季外,其他3个季节在近50年表现出显著的增加趋势,增幅为3.2~11.2 mm/10a,夏季增幅最大,秋季经历了80年代的降水小高峰后,近20年降水量略有下降。[结论]西天山北坡地区气候呈现暖湿化趋势。 展开更多
关键词 气候变化 气温 降水 西天山北坡地区
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迭山北坡云冷杉林火烧迹地灌木树种种间关联性 被引量:12
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作者 赵安 田青 +5 位作者 周晓雷 史瑞锦 黄海霞 曹雪萍 陆刚 周旭姣 《林业科学研究》 CSCD 北大核心 2022年第2期163-170,共8页
[目的]揭示青藏高原东北边缘迭山北坡云冷杉林火烧迹地灌木树种种间关联性。[方法]在调查数据的基础上,基于2×2列联表采用方差比率法(VR)、χ^(2)检验、联结系数(AC)和Jaccard相似系数(PC)4种方法,研究火烧迹地灌木群落17种灌木的... [目的]揭示青藏高原东北边缘迭山北坡云冷杉林火烧迹地灌木树种种间关联性。[方法]在调查数据的基础上,基于2×2列联表采用方差比率法(VR)、χ^(2)检验、联结系数(AC)和Jaccard相似系数(PC)4种方法,研究火烧迹地灌木群落17种灌木的种间关联性。[结果]总体联结性VR值等于0.93;χ^(2)检验显示有9个种对达到极显著正联结,2个种对达到显著联结,125个种对呈不显著联结;联结系数AC值在[0.6,1]的种对共有27对、在[0.2,0.6)的种对共有9对、在[-0.2,0.2)的种对共有40对,在[-0.6,-0.2)的种对共有13对,在[-1,-0.6)的种对共有47对;Jaccard相似系数PC值在[0.57,1]的种对共有17对、在[0.29,0.57)的种对共有12对、在[0,0.29)的种对共有107对,各研究方法得到的结果基本相似,但各检验方法存在一定的差异,结果显示各种对间的关联性不强,达到显著和极显著的种对很少,群落物种间总体联结性呈不显著负联结趋势。[结论]火烧迹地灌木树种种间的关联性不强,群落稳定性不高,灌木树种种间联结性主要受植物生物学特性、生态适应性和人为活动、土壤、气候、竞争以及化感作用等方面影响。 展开更多
关键词 青藏高原东北边缘 山北坡 灌木树种 种间关联性
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昆盖山北坡阿克吐兹—塔西克西韧性剪切带特征 被引量:3
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作者 高鹏 《新疆地质》 CAS CSCD 1998年第2期179-184,共6页
阿克吐兹—塔西克西韧性剪切带位于西昆仑昆盖山北坡 ,该韧性剪切带在空间上具有分带性 ,在时间上具有多期性 ,共划分了 3个构造变形期次。每期构造变形都有其特点 ,反映出该韧性剪切带具有多期构造叠加的属性。根据其组构特征分析 ,韧... 阿克吐兹—塔西克西韧性剪切带位于西昆仑昆盖山北坡 ,该韧性剪切带在空间上具有分带性 ,在时间上具有多期性 ,共划分了 3个构造变形期次。每期构造变形都有其特点 ,反映出该韧性剪切带具有多期构造叠加的属性。根据其组构特征分析 ,韧性剪切带的运动方向是由南西向北东方向运移 ,位移量为 1.94 km。 展开更多
关键词 西昆仑 昆盖山北坡 韧性剪切带 变形期次 运动方向 位移量
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昆盖山北坡苏古鲁克一带晚石炭世塔哈奇组生物地层特征 被引量:1
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作者 高鹏 肖忠 +2 位作者 卢兰英 刘通 田忠锋 《新疆地质》 CAS CSCD 北大核心 2009年第B12期76-79,共4页
研究区内晚石炭世塔哈奇组为一套浅海相碳酸盐岩建造,在该组中产有丰富的蜒类、珊瑚动物化石,根据化石组合特征,首次在该区建立了蜒类Triticites带,珊瑚Pseudozaphrentoides.mapingensis-P.nosovi组合带.
关键词 西昆仑昆盖山北坡 剖面概述 生物组合带 生物地层对比
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西昆仑昆盖山北坡硫铁矿地质特征与找矿远景 被引量:1
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作者 刘建伟 李玥 +1 位作者 余丙涛 樊振广 《四川地质学报》 2019年第2期229-233,共5页
昆盖山北坡区域矿产资源丰富,以火山岩型铜矿、铁矿、黄铁矿最具有工业价值,其次多为砂金和石膏矿等。通过在该地区以寻找海相火山岩型硫铁矿为主攻目标的工件,分析研究了该地区主要地层、岩石与成矿的时空关系和主要控矿构造空间形态... 昆盖山北坡区域矿产资源丰富,以火山岩型铜矿、铁矿、黄铁矿最具有工业价值,其次多为砂金和石膏矿等。通过在该地区以寻找海相火山岩型硫铁矿为主攻目标的工件,分析研究了该地区主要地层、岩石与成矿的时空关系和主要控矿构造空间形态及其变化;了解工作区矿石物质组分、矿石结构构造特征和矿石类型。通过研究,大致查明了工作区矿体数量、分布范围等,并圈定出成矿潜力较好,进一步勘查有重大突破的重点工作区三处,找矿靶区两处。 展开更多
关键词 硫铁矿 地质特征 找矿远景 西昆仑昆盖山北坡
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天山北坡大南沟河洪水成因分析及重现期研究
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作者 马哈提.穆拉提别克 《甘肃水利水电技术》 2013年第8期8-10,共3页
通过对天山北坡中段资料稀缺的小河流域地区洪水成因分析,总结出1962年以来大南沟河历史最大洪水,确定该场洪水的重现期为49年。对该流域河道规划、农田水利灌溉、水利工程建设和防汛抗旱有重要意义。
关键词 洪水成因 山北坡中段 大南沟河 重现期确定
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博罗科努山北坡金铜矿成因类型研究
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作者 龚龑君 张强 《中国金属通报》 2018年第10期23-23,25,共2页
博罗科努山北坡是金铜矿产丰富的地区,其地理位置较为特殊,位于非岩浆型大陆边缘。本地区的金矿以及铜矿数量众多,矿点也比较多。究其矿床成因,大概分为两种类型,一是流体~岩石反应堆积型,二是岩浆~热流体堆积型,之所以形成这两种类型... 博罗科努山北坡是金铜矿产丰富的地区,其地理位置较为特殊,位于非岩浆型大陆边缘。本地区的金矿以及铜矿数量众多,矿点也比较多。究其矿床成因,大概分为两种类型,一是流体~岩石反应堆积型,二是岩浆~热流体堆积型,之所以形成这两种类型,是受到了断裂构造活动的影响以及岩浆~花岗岩侵入体的控制。本文旨在对博罗科努山北坡金铜矿成因类型进行研究分析,详细阐述如下。 展开更多
关键词 成因类型 金铜矿 博罗科努山北坡
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中国西天山北坡表土花粉与区域植被关系 被引量:7
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作者 姚付龙 马春梅 +1 位作者 朱诚 杨海军 《古生物学报》 CAS CSCD 北大核心 2021年第3期471-482,共12页
天山是横亘中国西北的著名山系之一,将新疆分为南、北两个独立的地理区域,其自身也构成了一个完整的自然地理单元。因其山体海拔高,径向跨度大,纬向延伸长,气候、土壤和植被等自然地理要素各方面的区域差异,这对花粉搬运、传播、保存与... 天山是横亘中国西北的著名山系之一,将新疆分为南、北两个独立的地理区域,其自身也构成了一个完整的自然地理单元。因其山体海拔高,径向跨度大,纬向延伸长,气候、土壤和植被等自然地理要素各方面的区域差异,这对花粉搬运、传播、保存与沉积产生了显著影响。本文根据对西天山北坡采集的50个表土样品花粉分析,结合野外考察资料,揭示了该区域垂直方向上表土花粉组合与现代植被之间的关系,并进一步对天山表土花粉组合进行了区域对比。研究表明:(1)西天山北坡表土花粉谱可分为5个孢粉组合带,从山麓到山顶分别为山地荒漠带、草原带、森林带、亚高山草甸带、垫状植被带。(2)当云杉属花粉含量介于25%–30%时可认为该样品位于云杉林内,森林植被带花粉组合表现为以云杉属(Picea)–蒿属(Artemisia)–藜科(Chenopodiaceae)–伞形科(Apiaceae)为优势,亚高山草甸带和草原带以蒿属–藜科–禾本科(Poaceae)–云杉属–麻黄属(Ephedra)组合为主,山地荒漠带和垫状植被带以藜科–蒿属高含量为特征。云杉属花粉代表性较好,含量与现代植被分布相一致,但受气流影响显著。麻黄属含量和分布同样受气流影响,其含量不能指示该植被在样点周围存在与否。蒿属、藜科呈超代表性,只能指示区域生态意义,而禾本科则由于花粉产量低表现出低代表性。(3)西天山北坡植被带最为复杂,向东则逐渐简化。 展开更多
关键词 西天山北坡 表土花粉 云杉属 植被带 新疆
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虎爪山北坡旧石器地点调查报告 被引量:4
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作者 谭远辉 《湖南考古辑刊》 1999年第1期1-15+4,共15页
1988年4月,本所为配合原津市市委接待处(现为津市水利水电局)基建工程,在虎爪山顶部调查发现旧石器;同年5月,湖南省文物考古研究所试掘60平方米。1994年上半年,本市阳由乡砖厂在虎爪山北坡取土,至97年初,我们在砖厂取土过程中陆续采集... 1988年4月,本所为配合原津市市委接待处(现为津市水利水电局)基建工程,在虎爪山顶部调查发现旧石器;同年5月,湖南省文物考古研究所试掘60平方米。1994年上半年,本市阳由乡砖厂在虎爪山北坡取土,至97年初,我们在砖厂取土过程中陆续采集到石制品及石料126件。为区别原调查试掘的虎爪山旧石器地点,而将此地点称为“虎爪山北坡旧石器地点”。 展开更多
关键词 山北坡 地点 津市 旧石器 虎爪
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雅安老板山热性灌草丛草地资源调查 被引量:1
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作者 泽让东洲 仁青扎西 +1 位作者 王超 陈立坤 《草业与畜牧》 2012年第9期29-32,共4页
通过采用常规路线调查、求积仪法,对雅安市雨城区老板山北坡草地资源进行了初步调查。结果表明:老板山北坡草地为热性灌草丛类—多年生豆科草组—白三叶型;草地现有面积6.63hm2,可利用草地面积5.97hm2;全年产草量38384kg/hm2,全年可利... 通过采用常规路线调查、求积仪法,对雅安市雨城区老板山北坡草地资源进行了初步调查。结果表明:老板山北坡草地为热性灌草丛类—多年生豆科草组—白三叶型;草地现有面积6.63hm2,可利用草地面积5.97hm2;全年产草量38384kg/hm2,全年可利用牧草量19192kg/hm2;可载畜39.80个羊单位;为老板山北坡的利用提供基本参考数据。 展开更多
关键词 老板山北坡 草地资源 草地类型
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Influence of canopy on precipitation and its nutrient elements in broadleaved/Korean pine forest on the northern slope of Changbai Mountain 被引量:3
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作者 肖以华 代力民 +3 位作者 牛德奎 佟富春 陈高 邓红兵 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第3期201-204,251,共4页
The precipitation distribution quantity of canopy in broadleaved/Korean pine forest was measured during the growing season (Jun.–Sept.) in 2001 in the Changbai Mountain, Jilin Province, P. R. China. Results indicated... The precipitation distribution quantity of canopy in broadleaved/Korean pine forest was measured during the growing season (Jun.–Sept.) in 2001 in the Changbai Mountain, Jilin Province, P. R. China. Results indicated that the amounts of stemflow, throughfall, and interception were 37.39, 322.12 and 109.69 mm, accounting for 7.97%, 68.65% and 23.38% of the total rainfall, respectively. The rate of stemflow was higher in Jul. and Aug. than other months. The rate of throughfall dropped off from Jun. to Sept., however, rate of interception changed contrarily from 19.43% to 31.02% during the growing season. According to our analysis, the concentration of nutrient elements were arranged as Ca>Mg>N>K>Fe>P>Cu>Mn for rainfall, K>N>Mg>Ca>P>Fe>Mn>Cu for throughfall, and Mn>P>K>Cu>Fe>N>Mg>Ca for being leached through canopy. Nutrients concentration in stewflow and throughfall changed significantly when rainfall passed canopy, and concentration of all elements increased except for Ca and Mg. 展开更多
关键词 Broadleaved/Korean pine forest Precipitation distribution Concentration Nutrient elements CANOPY STEMFLOW THROUGHFALL INTERCEPTION
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Study on complexity of plant communities at different altitudes on the Northern Slope of Changbai Mountain 被引量:4
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作者 郝占庆 于德永 +1 位作者 邓红兵 姜萍 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第1期17-20,82,共4页
By the method of gradient pattern analysis, twenty plots were set at altitudes of 700-2600 m with an interval of 100 m on the northern slope of the Changbai Mountain. The dissimilarity of respective sub-plots in the s... By the method of gradient pattern analysis, twenty plots were set at altitudes of 700-2600 m with an interval of 100 m on the northern slope of the Changbai Mountain. The dissimilarity of respective sub-plots in the same community was measured and the complexity of plant communities at different altitudes was analyzed. The result from binary data of tree species in canopy tree indicated that the sub-plots in the communities, except subalpine Betula ermanii forest, showed comparatively high dissimilarity in species composition. Especially, the dissimilarity index (0.7) of broadleaved/Korean pine forest at low altitudes was obviously higher than other communities. The differences are not obvious between communities referring to dark coniferous forest. Comparatively, the dissimilarity in sub-plots of the communities at altitude of 1400 m was slightly higher than that of other communities, which reflected the complexity of tree species compositions of transitory-type communities. For subalpine Betula ermanii forest, tree species composition was simple and showed a high similarity between sub-plots. The results derived from binary data of shrub showed that the dissimilarity index of shrub species in broadleaved/Korean pine forest at low altitudes was higher than that in other communities, but the divergence tendency wasn抰 so obvious as that of arbor species. The dissimilarity derived from binary data of herb and all plant species at different altitudes showed greatly close tendency, and the differences in herb and all plant species between sub-plots were the greatest for the communities of broad-leaved-Korean pine forest and alpine tundra zone.. 展开更多
关键词 Changbai Mountain COMPLEXITY Plant community Altitude gradient
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Vegetation-environment Relationships Between Northern Slope of Karlik Mountain and Naomaohu Basin,East Tianshan Mountains 被引量:8
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作者 ZHANG Haiyan QIAN Yibing +1 位作者 WU Zhaoning WANG Zhongchen 《Chinese Geographical Science》 SCIE CSCD 2012年第3期288-301,共14页
Based on data from 22 sample plots and applying the Canonical Correspondence Analysis (CCA), this paper discusses the vegetation-environment relationships between the northern slope of Karlik Mountain and Naomaohu B... Based on data from 22 sample plots and applying the Canonical Correspondence Analysis (CCA), this paper discusses the vegetation-environment relationships between the northern slope of Karlik Mountain and Naomaohu Ba- sin, which is situated in the easternmost end of the Tianshan Mountains, Xinjiang Uygur Autonomous Region, China. For the zonal vegetation, community diversity of mountain vegetation is higher than that of the desert vegetation due to environmental factors. The CCA ordination diagram revealed that the composition and distribution of vegetation types are mainly determined by altitude, soil pH and soil salt content. With increasing elevation, the soil pH and total salt content decrease but the contents of soil organic matter, soil water, total nitrogen and total phosphorus increase gradu- ally. In the CCA ordination diagrams, the sample plots and main species can be divided into five types according to their adaptations to the environmental factors. Type Ⅰ is composed of desert vegetation distributed on the low moun- tains, hills, plains and deserts below an elevation of 1900 m; type Ⅱ is distributed in the mountain and desert ecotone with an elevation of 1900-2300 m, and includes steppe desert, desert steppe and wetland meadow; type Ⅲ is very sim- ply composed of only salinized meadow; type Ⅳ is distributed above an elevation of 2300 m, containing mountain steppe, meadow steppe, subalpine meadow and alpine meadow; type Ⅴ only contains salinized meadow. The results show that with increasing elevation, species combination changes from the xerophytic shrubs, semi-shrubs and herbs distributed in the low altitude zone with arid climate to the cold-tolerant perennial herbs growing in the high altitudinal zone with cold climate. 展开更多
关键词 vegetation pattern environmental factors canonical correspondence analysis (CCA) vegetation-environment relationships Tianshan Mountains XINJIANG
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Recent Climate Trends on the Northern Slopes of the Tianshan Mountains, Xinjiang, China 被引量:3
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作者 ZHANG Hongfeng OUYANG Zhiyun ZHENG Hua WANG Xiaoke 《Journal of Mountain Science》 SCIE CSCD 2009年第3期255-265,共11页
In arid regions, mountains fulfill important ecological and economic functions for the surrounding lowlands. In the scenario of global warming, mountain ecosystems change rapidly, especially in the arid region of nort... In arid regions, mountains fulfill important ecological and economic functions for the surrounding lowlands. In the scenario of global warming, mountain ecosystems change rapidly, especially in the arid region of northwestern China. This paper provides an assessment of the changes in temperature and precipitation in the historical records of climate on the northern slopes of the eastern Tianshan Mountains. A Mann-Kendall nonparametric trend and Sen's tests are employed to analyze the interannual changes and innerannual variability in temperature and precipitatiofi in the regions of low to high altitude. The present study finds that the largest increases in annual temperature are observed at stations in the low altitude regions. The significant increasing trends in temperature tend to occur mainly in late winter and early spring at stations from middle to high altitude, but in summer and autumn at stations of low altitudes. The increasing trends in annual precipitation are found from the middle to high altitude areas, but decreasing trends are found in the low altitude areas. The significant increasing trends in precipitation occur mostly in winter and earlier spring at stations from the middle to high altitudes, while the increasing and decreasing trend coexists at stations of low altitude with most of the significant trend changes occurring in March, June and August. 展开更多
关键词 Mountainous region Climate change Temperature PRECIPITATION China
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Regional Structure and Spatial Morphology Characteristics of Oasis Urban Agglomeration in Arid Area——A Case of Urban Agglomeration in Northern Slope of Tianshan Mountains,Northwest China 被引量:2
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作者 ZHANG Yufang YANG Degang +2 位作者 ZHANG Xinhuan DONG Wen ZHANG Xiaolei 《Chinese Geographical Science》 SCIE CSCD 2009年第4期341-348,共8页
It is great important to the health development of urban agglomeration to correctly understand the formation and development law of regional structure of urban agglomeration.Employing the analysis methods like fractal... It is great important to the health development of urban agglomeration to correctly understand the formation and development law of regional structure of urban agglomeration.Employing the analysis methods like fractal theory and quantitative statistics,coupling with the use of remote sensing images and other spatial data,this article discusses the urban agglomeration of oasis on the northern slope of the Tianshan Mountains in an arid area,and conducts the researches on its city scale,spatial distribution and individual form from 1990 to 2005.The result shows that it has loose hierarchical scale structure and polarization trend of population distribution while its hierarchical scale structure tends to mature.Under the influence of natural conditions,the spatial layout of urban agglomeration of oasis has macro characteristics that suggest cities distributed along oasis edges(dense or sparse),spatially expand along rivers,and cluster around traffic branches.The connectivity among the cities is high and shows an internal organization form of a banding distribution.The whole spatial shape of the internal structure of cities presents a "dumbbell" form,with mononuclear phenomenon receding and multi-nuclear appearing gradually.Individual cities spatially expand along rivers,portraying a long strip appearance.It indicates that the urban agglomeration of oasis shows regular and close structure but with a tendency to be complicated form and the loose structure.In the development of urban agglomeration,the authors recommend that the development of the city with good economic development conditions should be strengthened,and more attention be put into regional planning. 展开更多
关键词 fractal theory scale structure urban agglomeration of oasis Tianshan Mountains
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Characterization of Microbial Community Structure in Rhizosphere Soils of Cowskin Azalea(Rhododendron aureum Georgi)on Northern Slope of Changbai Mountains,China 被引量:1
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作者 ZHAO Wei QI Xiaojuan +2 位作者 LYU Jianwei YU Zhengxiang CHEN Xia 《Chinese Geographical Science》 SCIE CSCD 2016年第1期78-89,共12页
The vegetation and soil are mutual environmental factors, soil characteristics, such as chemical properties and microorganism that affect the vegetation occurrence, development and succession speed. In this study, we ... The vegetation and soil are mutual environmental factors, soil characteristics, such as chemical properties and microorganism that affect the vegetation occurrence, development and succession speed. In this study, we evaluated the structure of microbial communities of rhizosphere of Cowskin Azalea(Rhododendron aureum Georgi) populations and compared with non-rhizosphere soils at four sample sites of the Changbai Mountains, China, and analyzed the correlation between chemical properties of soil and microbial communities. The results showed that microbial structure and soil chemical properties are significant superior to non-rhizosphere at all four sample sites. The rhizosphere microorganisms are mainly composed of bacteria, actinomycetes, followed by fungi least. The principal component analysis(PCA) biplot displayed that there are differences between rhizosphere and non-rhizosphere soils for microflora; Through correlation analysis, we found that the bacteria is clearly influenced by p H on the Changbai Mountains, besides p H, other soil features such as NO3–-N. These data highlight that R. aureum as the dominant vegetation living in the alpine tundra is a key factor in the formation of soil microorganism and improving soil fertility, and is of great significance for the maintenance of alpine tundra ecosystem. 展开更多
关键词 Rhododendron aureum Georgi microbial community structure RHIZOSPHERE Changbai Mountains
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Regional Scale Rainfall- and Earthquake-triggered Landslide Susceptibility Assessment in Wudu County, China 被引量:8
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作者 BAI Shi-biao CHENG Chen +2 位作者 WANG Jian Benni THIEBES ZHANG Zhi-gang 《Journal of Mountain Science》 SCIE CSCD 2013年第5期743-753,共11页
Wudu County in northwestern China frequently experiences large-scale landslide events. High-magnitude earthquakes and heavy rainfall events are the major triggering factors in the region. The aim of this research is t... Wudu County in northwestern China frequently experiences large-scale landslide events. High-magnitude earthquakes and heavy rainfall events are the major triggering factors in the region. The aim of this research is to compare and combine landslide suseeptibility assessments of rainfall- triggered and earthquake-triggered landslide events in the study area using Geographical Information System (GIS) and a logistic regression model. Two separate susceptibility maps were produeed using inventories reflecting single landslide-triggering events, i.e., earthquakes and heavy rain storms. Two groups of landslides were utilized: one group eontaining all landslides triggered by extreme rainfall events between 1995 and 2003 and the other group containing slope failures caused by the 2008 Wenchuan earthquake. Subsequently, the individual maps were combined to illustrate the loeations of maximum landslide probability. The use of the resulting three landslide susceptibility maps for landslide forecasting, spatial planning and for developing emergency response actions are discussed. The eombined susceptibility map illustrates the total landslide susceptibility in the study area. 展开更多
关键词 LANDSLIDES Susceptibility assessment EARTHQUAKE Wudu County China
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