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地理经纬双向过渡带和复杂地形下气候的过渡性和特异性--以宜昌市为例 被引量:1
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作者 毛成忠 肖湛臻 +3 位作者 杨志彪 雷东洋 孟芳 覃金华 《中低纬山地气象》 2023年第1期31-37,共7页
宜昌处在我国地形第二、第三级阶梯的过渡地带,又位于我国南北过渡带秦巴山地南麓的中低纬度过渡带,长江中上游结合部,山地河谷平原并存,地形复杂,垂直高差大。气候资料分析和文献调研表明,宜昌天气气候因特殊地理环境具有过渡性和特异... 宜昌处在我国地形第二、第三级阶梯的过渡地带,又位于我国南北过渡带秦巴山地南麓的中低纬度过渡带,长江中上游结合部,山地河谷平原并存,地形复杂,垂直高差大。气候资料分析和文献调研表明,宜昌天气气候因特殊地理环境具有过渡性和特异性:(1)年平均气温主要随地形高度递减,年总降水量主要随纬度升高减小。(2)年暴雨日数、连阴雨天数,在中西部随纬度升高而递减,等值线近似纬向排列;东部随地形升高而递增,等值线近似经向排列。(3)山地平原过渡带地形的阻挡滞留、辐合抬升等对极端短时强降水有明显加强作用,这种作用在秦岭与黄淮过渡带、太行山与华北平原过渡带有相似的天气气候效应。(4)宜昌位于江淮梅雨的西界、华西秋雨的东界,具有天气气候“分水岭”特征。(5)宜昌是暴雨雨团、西南涡移动的主要通道之一。 展开更多
关键词 地理过渡 气候过渡性 迎风坡 极端强降水 江淮梅雨 华西秋雨 暴雨雨团 西南涡
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“深圳—巴彦浩特”地理样带土地利用及其对生态资产的影响 被引量:4
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作者 杜鹃 蒲秋 史培军 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 2005年第5期531-535,F0003,共6页
在建立“深圳—巴彦浩特”地理样带基础地理数据库的基础上,分析了研究区1995—2000年土地利用、生态资产的变化特征以及土地利用变化对生态资产的影响.结果表明,样带土地利用变化受快速城市化、产业结构调整和生态环境改善政策驱动的... 在建立“深圳—巴彦浩特”地理样带基础地理数据库的基础上,分析了研究区1995—2000年土地利用、生态资产的变化特征以及土地利用变化对生态资产的影响.结果表明,样带土地利用变化受快速城市化、产业结构调整和生态环境改善政策驱动的影响显著.土地利用的主要类型由耕地向林地转变,使得样带2000年的生态资产比1995年增加了899亿元,样带上湿地(包括水体)的增加对生态资产总量的保持和提高有重要作用.另一方面,城市化和荒漠化也使得样带局部地区出现了生态资产的降低. 展开更多
关键词 地理 土地利用变化 生态资产 深圳-巴彦浩特
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“深圳—巴彦浩特”地理样带土地利用与水旱灾害研究 被引量:2
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作者 蒲秋 杜鹃 史培军 《自然灾害学报》 CSCD 北大核心 2005年第6期71-76,共6页
在建立1990-2000年“深圳—巴彦浩特”地理样带水旱灾害数据库的基础上,结合样带1995、2000年两期的土地利用数据,分析了样带水旱灾害的区域差异,及其与样带土地利用时空格局的关系。结果表明,样带水旱灾害呈现较强的南北差异,北方以旱... 在建立1990-2000年“深圳—巴彦浩特”地理样带水旱灾害数据库的基础上,结合样带1995、2000年两期的土地利用数据,分析了样带水旱灾害的区域差异,及其与样带土地利用时空格局的关系。结果表明,样带水旱灾害呈现较强的南北差异,北方以旱灾为主,南方以水灾为主;土地利用结构对样带水旱灾害有较强的影响,土地利用类型复杂的县市有较高的水旱灾害发生率,而土地利用类型单一的县市则受水旱灾害影响较小。水灾主要出现在样带南部多种土地利用类型混杂的县市,特别是城镇建设用地比例较高的地区,水灾相对更为频繁;旱灾在缺乏灌溉水源且以耕地和草地为主要土地利用类型的区域发生频率较高。 展开更多
关键词 深圳-巴彦浩特 地理 土地利用格局 水旱灾害
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北祁连造山带志留纪岩相古地理研究 被引量:1
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作者 牟传龙 侯乾 +2 位作者 郑斌嵩 葛祥英 昝博文 《沉积与特提斯地质》 CAS CSCD 2020年第3期48-58,共11页
奥陶纪—泥盆纪时期,受加里东构造活动的影响,北祁连洋盆经历了俯冲消亡至造山的复杂转换。其中,志留纪是记录了盆山转换的重要大地构造过渡阶段,然而北祁连造山带在该时期的盆地性质一直存在争议。本文对北祁连地区志留系沉积地层开展... 奥陶纪—泥盆纪时期,受加里东构造活动的影响,北祁连洋盆经历了俯冲消亡至造山的复杂转换。其中,志留纪是记录了盆山转换的重要大地构造过渡阶段,然而北祁连造山带在该时期的盆地性质一直存在争议。本文对北祁连地区志留系沉积地层开展了详细的野外地质调查及室内测试分析,通过岩性、沉积构造和古生物化石组合等方面的研究,共识别出潮坪相、浅海陆棚相及半深海相三种沉积相类型。此外,基于前人的研究成果和本研究的新资料,编制了全新的北祁连地区志留纪沉积构造格架、沉积盆地类型及空间配置关系图。在此基础上,通过区域地层对比,以及岩相古地理编图研究,重建了北祁连造山带志留纪沉积盆地充填序列,并采用造山带岩相古地理编图方法编制了全新的研究区志留纪岩相古地理图。 展开更多
关键词 北祁连造山 志留纪 造山岩相古地理
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造山带古地理学——重建区域构造古地理的若干思考 被引量:31
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作者 吴根耀 《古地理学报》 CAS CSCD 2007年第6期635-650,共16页
以活动论构造观为指导,尽可能客观地复原地史期间海陆面貌和盆山格局的关键是在给定时间约束之后,于研究区现存的地质记录中发现业已消失了的和后期才出现的构造古地理单元。文章基于大量实例论述了可能导致构造古地理单元消失和后期出... 以活动论构造观为指导,尽可能客观地复原地史期间海陆面貌和盆山格局的关键是在给定时间约束之后,于研究区现存的地质记录中发现业已消失了的和后期才出现的构造古地理单元。文章基于大量实例论述了可能导致构造古地理单元消失和后期出现的各种情况,如大陆地块的解体、沉没、俯冲、剥蚀、冲断—推(滑)覆作用、走滑作用、碎裂和被卷入年轻造山带等,特别提出东亚大陆边缘地区自侏罗纪末开始的移置地体拼贴增生是该区的一大特点。构造古地理单元消失和后期出现的发生大都与巨型断裂带(尤其是作为构造边界的巨型断裂带)发育有关。陆内阶段的断裂带活动对盆山格局的变化、盆地发育、沉积演化及其关键地质事件有明显的控制作用,还应注意断裂带解体阶段出现的新生构造对古地理重建的制约。简言之,造山带古地理学的发展是推动构造古地理学前进的关键之一,在恢复古特提斯多岛洋的构造古地理面貌、重建全球古大陆演化尤其是造山带和经受造山运动改造地区的古大陆演化,有着积极的不可或缺的作用。 展开更多
关键词 造山地理 构造古地理单元 盆山格局 地理重建
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造山带古地理学——在盆地构造古地理重建中的若干思考 被引量:26
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作者 吴根耀 《古地理学报》 CAS CSCD 2005年第3期405-416,共12页
造山带古地理学在盆地构造古地理重建中若干思考的核心,是以活动论的构造观指导盆地分析。本文强调以发展的、动态演化的思路来研究盆地。现存的一个盆地,可能只是地史期间大盆地的残余(或残留)部分;或是原来彼此分开和独立的几个盆地... 造山带古地理学在盆地构造古地理重建中若干思考的核心,是以活动论的构造观指导盆地分析。本文强调以发展的、动态演化的思路来研究盆地。现存的一个盆地,可能只是地史期间大盆地的残余(或残留)部分;或是原来彼此分开和独立的几个盆地内的沉积记录组成的沉积物拼盘。一个盆地内现存的次级构造单元可能由年轻的造山运动形成;另一种可能性则是原来的次级单元已被后来的构造-热事件模糊或遮蔽了。在盆地的建造过程中,隆起(包括次级隆起)的时起时伏十分常见;相应地,盆地间的时分时合也十分常见。在泛大陆旋回与大盆地发育间有着内在联系,即大盆地发育受邻侧的洋盆演化和造山过程制约,故“盆”“山”间的耦合分析是正确认识盆地动态演化的钥匙。体现在构造古地理重建中,造山带古地理学倡导原地的古地理重建与非原地的古地理重建相结合且以后者为主。非原地的古地理重建可通过定量的(如基于古地磁资料的重建)和定性的两条途径实现。文章讨论了定性重建中的5个要点1)时间上,要结合“反序”的研究,2)空间上,要结合“反转构造”的研究,3)强调构造复位在古地理重建中的意义,4)盆地建造阶段中的改造事件所起的承前启后作用,5)盆地动力学与造山动力学的结合研究。 展开更多
关键词 造山地理 科学发展观 动态演化 非原地的古地理重建 盆地分析 地理重建 盆地构造 地理 造山 次级构造单元
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武威市猪寄生虫感染调查 被引量:1
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作者 王权 马更尕 于天明 《畜牧兽医杂志》 2015年第2期92-92,94,共2页
武威市位于甘肃省中部,河西走廊东端,东接兰州市、南靠祁连山,北接腾格里沙漠,西通金昌市。现辖凉州区、民勤县、古浪县和天祝藏族自治县,总面积330万hm2。武威地势南高北低,相对高差为3 854m,形成明显的三个地理带:南部祁连山区高寒阴... 武威市位于甘肃省中部,河西走廊东端,东接兰州市、南靠祁连山,北接腾格里沙漠,西通金昌市。现辖凉州区、民勤县、古浪县和天祝藏族自治县,总面积330万hm2。武威地势南高北低,相对高差为3 854m,形成明显的三个地理带:南部祁连山区高寒阴湿;中部绿洲灌溉区属温带干旱区,昼夜温差较大,年降水量102~2 000 mm;北部干旱区干旱缺水,年降水量52~185mm。 展开更多
关键词 地理带 寄生虫感染 河西走廊东端 灌溉区 光热资源 年降水量 天祝藏族自治县 甘肃省中部 祁连山区 高寒阴湿
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Forest resources variation along with the main rivers in typical forest re-gion of Changbai Mountain 被引量:1
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作者 郝占庆 于德永 +2 位作者 林凡 熊在平 叶吉 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第2期101-106,i001,共7页
The restoration of the riparian vegetation disturbed by human activities is one of the hotspots of watershed ecology. Through interpreting the images of Remote Sensing in 1985 and 1999, the basic information of forest... The restoration of the riparian vegetation disturbed by human activities is one of the hotspots of watershed ecology. Through interpreting the images of Remote Sensing in 1985 and 1999, the basic information of forest resources of Lushuihe Forest Bureau, which is a typical forest area of Changbai Mountain, was obtained with support of GIS. By dividing Land covers of Lushuihe area into 10 types (water body, residential land, stump land, farming land, wetland, mature conifer forest, midlife conifer forest, mature broadleaf forest, midlife broadleaf forest, and man-made young forest) and dividing the riparian zone into four buffers (in turn, 1000, 2000, 3000, 4000 m away from the river), the changes of riparian forest resources during 1985-1999 were analyzed. The results showed that the deforestation intension has obviously decreased and the whole environment has been evidently improved, but the riparian ecosystem was still flimsy. In buffer 1, 2, 3, the area of midlife conifer forest increased largely, but the areas of other types of land covers all decreased. Midlife conifer forest had a comparatively good status in the three buffers. In buffer 4, midlife conifer forest, mature conifer forest, and mature broadleaf forest formed a forest-age rank that is helpful to stabilize the forest ecosystem and exert its functions. Area percentage of wetland decreased in buffer 1, buffer 2, and buffer 3, even in buffer 4 in which forest ecosystem rehabilitated comparatively well, so protecting and rehabilitating wetland is a very difficult task. 展开更多
关键词 Forest resources BUFFER Riparian belt Remote sensing GIS
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初论造山带古地理学 被引量:48
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作者 吴根耀 《地层学杂志》 CSCD 北大核心 2003年第2期81-98,115,共19页
造山带古地理学属构造古地理学 ,是造山带地层学的姐妹学科 ,其核心是活动论构造观。简述了造山带古地理学的形成和内涵 ,重点讨论了地质记录已发生移位、歪曲和混杂的造山带地区 (或经造山作用改造的克拉通地区 )正确地进行构造—古地... 造山带古地理学属构造古地理学 ,是造山带地层学的姐妹学科 ,其核心是活动论构造观。简述了造山带古地理学的形成和内涵 ,重点讨论了地质记录已发生移位、歪曲和混杂的造山带地区 (或经造山作用改造的克拉通地区 )正确地进行构造—古地理重建的三个问题 :一是不能用“将今论古”的方法恢复地史期间的隆起区和堆积区 ,地史期间的物源区并非一成不变 ,要充分认识物源供应的多样性和多重性 ;二是沉积相带的展布受区域构造应力场及基底构造格局控制 ,要特别重视边缘相及其物源区的研究 ;三是辨析原生沉积盆地与构造盆地 ,对盆地进行正确的构造复位是古地理重建的基础。 展开更多
关键词 造山地理 构造古地理 地质记录 造山作用 克拉通地区 区域构造应力场 原生沉积盆地
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榆阳区沙地饲料桑引进栽培技术 被引量:1
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作者 边菊萍 杨军卫 《中国畜牧兽医文摘》 2016年第4期231-231,共1页
1基本概况 榆阳区位于陕西省北部,毛乌素沙漠与黄土丘陵区接壤地带。以古长城为界,北部是风沙草滩区,占总面积的76.1%;南部是丘陵沟壑区,占总面积的23.9%。"七沙二山一分田"是本地区的地貌特征。该区处于内陆干草原自然地理带,属寒... 1基本概况 榆阳区位于陕西省北部,毛乌素沙漠与黄土丘陵区接壤地带。以古长城为界,北部是风沙草滩区,占总面积的76.1%;南部是丘陵沟壑区,占总面积的23.9%。"七沙二山一分田"是本地区的地貌特征。该区处于内陆干草原自然地理带,属寒温带半干旱季风区,气候寒温,雨量稀少,日照充足,四季分明。 展开更多
关键词 榆阳区 地理带 陕西省北部 丘陵沟壑区 干草原 接壤地 季风区 古长城 年平均气温 春季干旱
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浅谈地图语言的识读与信息传输
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作者 李慧 《皖西学院学报》 1994年第4期69-70,56,共3页
地图是一种符号语言,其中潜存着丰富的信息,本文通过阐述地图单个符号、组合符号及注记信息的关系,介绍了一种地图的阅读方法。
关键词 地图语言 组合符号 信息传输 地势图 符号语言 岩溶作用 地理带 轮廓图 分层设色图 分水线
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阿其图乌拉地区下白垩统赛汉组层序地层与铀成矿远景预测 被引量:2
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作者 刘波 杨建新 +1 位作者 谷峰 张锋 《矿产与地质》 2017年第3期437-444,共8页
阿其图乌拉凹陷位于苏尼特隆起内,凹陷周缘铀源条件较好,通过实地工作及前人资料整理,研究该地区沉积相、沉积构造和测井相等特征,建立测井相、测井相标志。研究认为该地区下白垩统赛汉组发育浅水辫状河三角洲-滨浅湖沉积体系。层序地... 阿其图乌拉凹陷位于苏尼特隆起内,凹陷周缘铀源条件较好,通过实地工作及前人资料整理,研究该地区沉积相、沉积构造和测井相等特征,建立测井相、测井相标志。研究认为该地区下白垩统赛汉组发育浅水辫状河三角洲-滨浅湖沉积体系。层序地层分析可精细研究不同时期沉积充填序列,并可进行等时地层对比。通过标准层序地层分析,将赛汉组共分为4个体系域类型,分别为湖侵体系域、高位体系域、下降期体系域及低位体系域,其中高位体系域及下降期体系域具有铀储层好、岩石还原容量高的特点。矿化异常主要产于高位及下降期体系域内。通过各体系域"层序-氧化带-岩相古地理"编图,提出"层序地层-储层-氧化带预测技术",并圈定Ⅰ、Ⅱ号成矿远景区,并认为Ⅱ号成矿远景区辫状河前缘砂体具有铀储集性能好、还原容量高的特点,可先开展钻探验证工作。 展开更多
关键词 层序地层 铀储层 层序-氧化-岩相古地理 成矿远景区 阿其图乌拉地区
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北纬40度的守望——大连与喀什地震台的精神版图
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作者 王甫 董晓光 《防灾博览》 2015年第2期40-47,共8页
在我们这个小小的星球上,北纬40度线绵延不绝横亘于美国、日本、地中海地区和中国大陆。在形似雄鸡的中国版图上,北纬40度线地区穿越首都北京,贯通祖国最辽阔的东西疆域,成为人们最关注的地理带、经济带、文化带。
关键词 地震台 地理带 地中海地区 文化 绵延不绝 中国地震 电感应力仪 人烟稀少 震相 黄瑜
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2015年4-5月尼泊尔地震的地震构造:基于余震样式、地表效应及形变特征的分析评估
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作者 Revathy M.Parameswaran Thulasiraman Natarajan +8 位作者 Kusala Rajendran C.P.Rajendran Rishav Mallick Matthew Wood Harish C.Lekhak 胡亚轩(译) 宋尚武(译) 李煜航(校) 白志明(复校) 《世界地震译丛》 2016年第2期111-129,共19页
2015年4月25日尼泊尔中部的廓尔喀发生了M_W7.8地震,随后的5月12日,在距此震震中以东约140km处又发生了M_W7.3地震。这两次地震的发生为我们理解喜马拉雅山的地震提供了新的视角和机遇。本文试图基于这两次事件所产生的形变场以及它们... 2015年4月25日尼泊尔中部的廓尔喀发生了M_W7.8地震,随后的5月12日,在距此震震中以东约140km处又发生了M_W7.3地震。这两次地震的发生为我们理解喜马拉雅山的地震提供了新的视角和机遇。本文试图基于这两次事件所产生的形变场以及它们余震的时空特征分析这些地震的地震构造。结合震后对当地的破坏和地表形变等的实地考察可明显看出,尽管主震滑动主要局限于主喜马拉雅逆冲断裂(MHT),但破裂并没有扩展至主前缘逆冲断裂(MFT)。由形变场现有的合成孔径雷达干涉测量图像支持的野外证据表明,滑动分量可能在先前识别出的失序逆冲/活动逆冲区出现,该区域平行于主中央逆冲断裂(MCT),即文献中描述的与地形一致的地理转换带PT_2。第一次破裂终止后触发了第二次大地震,余震的分布在空间上仍局限在PT_2最东端。2015年发震序列的机理表明,失序逆冲断层吸收了部分滑移量,依据当前对地震机理的理解,此次地震始于主喜马拉雅逆冲断裂。 展开更多
关键词 地震活动性 尼泊尔喜马拉雅 震群 地表形变 余震 自然地理转换 失序逆冲断层
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Diversity and Geographical Pattern of Altitudinal Belts in the Hengduan Mountains in China 被引量:12
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作者 YAO Yonghui ZHANG Baiping HAN Fang, PANG Yu 《Journal of Mountain Science》 SCIE CSCD 2010年第2期123-132,共10页
This paper analyses the diversity and spatial pattern of the altitudinal belts in the Hengduan Mountains in China. A total of 7 types of base belts and 26 types of altitudinal belts are identified in the study region.... This paper analyses the diversity and spatial pattern of the altitudinal belts in the Hengduan Mountains in China. A total of 7 types of base belts and 26 types of altitudinal belts are identified in the study region. The main altitudinal belt lines, such as forest line, the upper limit of dark coniferous forest and snow line, have similar latitudinal and longitudinal spatial patterns, namely, arched quadratic curve model with latitudes and concave quadratic curve model along longitudinal direction. These patterns can be together ealled as "Hyperbolic-paraboloid model", revealing the complexity and speciality of the environment and ecology in the study region. This result further validates the hypnosis of a common quadratic model for spatial pattern of mountain altitudinal belts proposed by the authors. The spatial pattern of altitudinal belts is closely related with moisture-related exposure effect in the Hengduan Mountains. Different combinations (spectra) of altitudinal belts and different base belt types appear in windward and leeward flanks and even in the same flanks of different ranges. This is closely related with the parallel mountain ranges of the Hengduan Mountains, which, at nearly right angle with the moving direction of prevailing moisture-laden air masses from west and east, hold up the warm and humid monsoon wind from moving into the core region and result in different moisture conditions in windward and leeward flanks. However, how to quantitatively describe the moisture-related exposure effect needs further study. In addition, the data quality and data accuracy at present also affect to some extent the result of quantitative modeling and should be improved with RS/GIS in the future. 展开更多
关键词 Hengduan Mountains Altitudinal belt spectra Exposure effect Quadratic model
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Treatment of Acid Mine Drainage Using Constructed Wetland in Tropical Environment: A Tanzania Case Report 被引量:1
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作者 Jamidu Hizzam Yahaya Katima Leonard Gastory Lugali Karoli Nicholas Njau 《Journal of Agricultural Science and Technology(B)》 2013年第6期439-446,共8页
The suitability of constructed wetland (CW) in were developed. The first experiment focused on zinc and treating acid mine drainage (AMD) was investigated. Two experiments nutrients removals. Four units of horizon... The suitability of constructed wetland (CW) in were developed. The first experiment focused on zinc and treating acid mine drainage (AMD) was investigated. Two experiments nutrients removals. Four units of horizontal subsurface flow CWs were used, two cells planted with Phragmites mauritianus, one cell with Typha domingensis and one cell unplanted (control cell). Artificial high concentrated AMD was used. It was mixed with domestic wastewater from the anaerobic waste stabilization pond (WSP) to ensure nutrient supply to the plants in the CW cells. The second experiment tested the tolerance of locally available macrophytes to the harsh acidic environment, while providing required condition for treatment of AMD. To accomplish this, another set of four CW cells planted with different types of macrophytes, namely Typha domingensis, Phragmites mauritianus, Vetiver grass and Papyrus, were used thereby subjecting them to varying acid concentration ofpH of 3.5, 3.0, 2.9 and 2.7. The study demonstrated adequate zinc removal from AMD which is related to sulphide precipitation. A CW cell planted with Typha domingensis showed higher zinc removal (80%-84%) compared to other cells. Different macrophytes showed different nutrient removal efficiency, but overall, for the type of wetland plants studied, phosphorous removal increased with decreasing pH while nitrogen removal behaved quite opposite. On the other hand, Typha domingensis, Phragmites mauritianus and Papyrus were observed to tolerate high acidity as low pH as 2.7 and therefore are suitable macrophytes for AMD treatment with CW. 展开更多
关键词 Constructed wetland acid mine drainage passive system zinc removal suitable macrophytes
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A DISCUSSION ON BIOGEOGRAPHICAL LINES OF THE TROPICAL SUBTROPICAL YUNNAN 被引量:6
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作者 ZHUHua YANLi-chun 《Chinese Geographical Science》 SCIE CSCD 2002年第1期90-96,共7页
Based on comparative studies on four regional floras from northwest, west, south and southeast of Yunnan respectively, the formerly suggested two biogeographical lines, i.e. the “Tanaka Line" and the “Ecogeogra... Based on comparative studies on four regional floras from northwest, west, south and southeast of Yunnan respectively, the formerly suggested two biogeographical lines, i.e. the “Tanaka Line" and the “Ecogeographical Diagonal Line", both going from northwest to southeast of Yunnan, and their significance are discussed. In family and generic levels, similarity coefficients among the four compared floras are more than 93% and 60% separately, which indicate the close floristic affinities among them. The highest similarity coefficient, i.e. 98.7% in family level and 78.6% in generic level separately, is found between the regional flora of northwest Yunnan and the flora of southeast Yunnan although these two regions are the most distant away each other among the compared regional floras. The flora of northwest Yunnan is also the most similar to the flora of southeast Yunnan in floristic composition. These support the idea of “Ecogeographical Diagonal Line". In specific level, the relatively high similarity coefficient is between the regional flora of west Yunnan and the one of south Yunnan. The floristic affinities among these regional floras and some distribution patterns could be explained by the geological history and tectonic theory of Yunnan. 展开更多
关键词 biogeographical lines floristic affinity YUNNAN
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The features of physical geography in the transitional region between Qinling Mountains and Huanghuai Plain
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作者 马建华 李剑 千怀遂 《Journal of Geographical Sciences》 SCIE CSCD 2004年第4期437-446,共10页
The features of physical geography in the transitional region between Qinling Mountains and Huanghuai Plain possess transitional characters evidently in two directions: one is from the western mountain to the eastern ... The features of physical geography in the transitional region between Qinling Mountains and Huanghuai Plain possess transitional characters evidently in two directions: one is from the western mountain to the eastern plain and the other is from southern subtropical zone to northern temperate zone. Torrential rain, especially strong torrential rain is frequent in the transitional region, and there are many torrential rain centers. A majority of torrential rain is distributed among 100-200 m asl. The winter temperature at 100-400 m asl is higher than that in Huanghuai Plain whose altitude is lower than that of the transitional region, and the highest temperature in January appears at 350-400 m asl.The thickness of warm slope belt in the transitional region varies from 100 m to 250 m asl. The formation of torrential rain and warm slope belt is the result of joint action of atmospheric circulation and local terrain. Frequent torrential rains and warm slope belt had tremendous influences on the soil properties, plant distribution and local climate in the transitional region. 展开更多
关键词 qinling mountains huanghuai plain characters of physical geography torrential rain warm slope belt
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Research Progress of Cold Resistance Mechanism of Cassava 被引量:1
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作者 Wei ZHANG Tuo YI +1 位作者 Yong WU Yong SONG 《Agricultural Science & Technology》 CAS 2017年第9期1607-1614,共8页
Cassava is vulnerable to frost and snow, so it is suitable for planting in tropical and subtropical region. Low temperature is an important environment factor affecting the growth and development and production of cas... Cassava is vulnerable to frost and snow, so it is suitable for planting in tropical and subtropical region. Low temperature is an important environment factor affecting the growth and development and production of cassava, and the region with annual average temperature below 15 ℃ is not conducive to its normal growth and development. The improvement of cold resistance of cassava can increase the planting area and improve the yield and quality of cassava. In this study, morphological,physiological and biochemical and molecular researches on cold resistance of cassava, as well as the latest research progress,were reviewed in this paper. At the same time, some potential difficulties in the research on cold resistance of cassava were put forward, and the future work focus was also discussed. 展开更多
关键词 CASSAVA Low temperature Cold resistance Physiology and Biochemistry Research progress
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Soil indicators for eco-geographic regionalization:A case study in mid-temperate zone of eastern China
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作者 刘晔 吴绍洪 +1 位作者 郑度 戴尔阜 《Journal of Geographical Sciences》 SCIE CSCD 2009年第2期200-212,共13页
Eco-geographic regional system is formed by division or combination of natural features based on geographic relativity and comparison of major ecosystem factors(including biological and non-biological) and geographic ... Eco-geographic regional system is formed by division or combination of natural features based on geographic relativity and comparison of major ecosystem factors(including biological and non-biological) and geographic zonality.In previous studies, soil types were often taken as a basis for soil regionalization.However, the quantitative characteristics of soil indicators are fitter than the qualitative ones of soil types for modern regionalization researches.Based on the second China's national soil survey data and the provincial soil resource information, by principal analysis and discriminant analysis, this paper discusses the appropriate soil indicators as the complement of eco-geographic region indicator systems and the relationships between these soil indicators and soil types in regionalization.The results show that five indicators are used in eco-geographic zonality in mid-temperate zone of eastern China which are organic matter content, cation exchange capacity, pH, clay content and bulk density in topsoils.With a regression-kriging approach, the maps of soil indicators in mid-temperate zone of eastern China are compiled with a resolution of 1 km in every grid and the indicative meanings of these soil indicators are discussed.By cluster analysis it is proved that these soil indicators are better than the soil types and soil regionalization in delineating eco-geographic regions. 展开更多
关键词 eco-geographic zone soil indicators mid-temperate zone of eastern China
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