土地利用变化对全球气候影响的研究进展与方法初探   总被引：10，自引：0，他引：10  

刘纪远  邵全琴  延晓冬  樊江文  邓祥征  战金艳  高学杰  黄麟  徐新良  胡云峰  王军邦  匡文慧 《地球科学进展》2011,26(10):1015-1022

综合分析了土地利用与土地覆盖变化（LUCC）对全球气候影响研究的重要科学问题和国内外研究现状,在此基础上,考虑各学科的相互交叉、渗透和耦合等特点,提出并初步设计了土地利用变化对全球气候影响研究的星地一体化LUCC—气候—生态系统耦合研究技术方法体系,并就土地利用变化对全球气候影响的LUCC演变规律及动力学机制、LUCC...  相似文献   

A 2200-year Record of Seabird Population on Ganquan Island, South China Sea     

XU Liqiang  LIU Xiaodong  SUN Liguang  YAN Hong  LIU Yi  LUO Yuhan  HUANG Jing 《《地质学报》英文版》2011,85(4):957-967

Geochemical characteristics of a 107 cm long sediment profile, collected from Ganquan Island, South China Sea, were analyzed. Based on concentrations of bio-elements (Cu, Zn, Cd, Ba, As, Se, P), 210Pb and AMS14C dating, we reconstructed seabird population of Ganquan Island over the past 2200 years. Seabirds inhabited this island more than 2200 years ago, and their population displayed remarkable fluctuations with two peaks around 2100–1850 yr BP and 900–300 yr BP, respectively. The seabird population change profile on Ganquan Island is similar to that on Dongdao Island over the past 1800 years. We examined the relationship between the seabird population and climate, and found it quite complicated. The seabird population did not reach the maximum during the Medical Warm Period (MWP) with relatively high average temperature; however, it remained near the peak value for about 600 years during the climatic transition period and the Little Ice Age (LIA), indicating that a relatively cool climate is favorable for seabirds on Ganquan Island.  相似文献   

山西太原组和山西组煤类分布特征及变质作用分析     

解锡超  张庆辉  唐跃刚  张正喜  王海生  侯贤旭  陈小栋  苏育飞  王聪  贾龙 《中国煤炭地质》2011,(8):78-81

山西煤类齐全,煤质较优良,是我国主要的炼焦煤和无烟煤基地。以山西多年来的煤炭资源预测资料和众多矿区勘查资料为基础,全面总结了山西省太原组和山西组煤类分布特征及其变质作用。研究认为,山西的煤类分布具有明显的南北分带性,38°线以北煤变质程度较低,煤类较单一,以气煤为主;38°线以南煤变质程度相对较高,煤类较多;山西省煤变质类型主要有深成变质、岩浆热变质和接触变质三种类型,深成变质是基础,也是山西省最重要的变质类型,岩浆热变质主要是燕山期岩浆活动叠加于深成变质的基础上造成的,接触变质只是局部的,对区域性的变质影响甚微。研究成果可以为山西省煤炭资源的合理利用提供依据。  相似文献   

乐清湾悬沙输移机制分析   总被引：1，自引：0，他引：1  

杨晓东  姚炎明  蒋国俊  李佳 《海洋通报》2011,30(1):53-59

以乐清湾海区特征测站实测资料为据,运用机制分解法将悬沙净输移通量分解成多个动力项并讨论不同区域悬沙输移的时空分布特征,认为潮泵输沙在湾内贡献均较大,在浅滩附近占明显优势,垂向净环流输沙在小潮期中,内湾作用显著,平流输沙在开阔水域及中湾深槽起主要作用.从余流分布、流速与含沙量的相位关系、垂向余流结构与悬沙浓度垂向梯度变化...  相似文献   

塔里木河下游土壤水分和地下水位变化对植被的影响   总被引：4，自引：0，他引：4  

马晓东  陈亚宁  朱成刚  李卫红 《地理学报(英文版)》2011,21(1):150-162

Based on data collected over five years of monitoring the Lower Tarim River,we analyzed the variability of soil moisture content (SMC) and the relationship between SMC,groundwater table depth (GWD) and vegetation by using the methods of coefficient of variation (Cv),Pearson correlation and regression. The results of the variability of SMC indicate that it rose with increase in depth of soil layer -SMC in the soil layer of 0-60 cm was relatively small compared to SMC in the soil layer of 100-260 cm which showed a significant increase in variability. SMC and GWD before and after ecological water diversions exhibited significant differences at the site of the Yingsu transect and its vicinity of the watercourse,especially SMC in the soil layer of 100-260 cm increased significantly with a significant rise of GWD and reached maximum values at a GWD of about 4 m. Plant coverage and species diversity significantly improved with increases in SMC in the soil layer of 100-260 cm,both of them approached the maximum values and 92.3% of major plant species were able to grow when SMC was > 10%. To restore the ecosystem of desert riparian forest along the Lower Tarim River,the GWD must be maintained at < 4 m in the vicinity of the watercourse and at about 4 m for the rest of this arid region.  相似文献   

The variation in soil moisture and the appropriate groundwater table for desert riparian forest along the Lower Tarim River     

MA Xiaodong  CHEN Yaning  ZHU Chenggang  LI Weihong 《地理学报》2011,21(1):150-162

Based on data collected over five years of monitoring the Lower Tarim River, we analyzed the variability of soil moisture content (SMC) and the relationship between SMC, groundwater table depth (GWD) and vegetation by using the methods of coefficient of variation (Cv), Pearson correlation and regression. The results of the variability of SMC indicate that it rose with increase in depth of soil layer – SMC in the soil layer of 0–60 cm was relatively small compared to SMC in the soil layer of 100–260 cm which showed a significant increase in variability. SMC and GWD before and after ecological water diversions exhibited significant differences at the site of the Yingsu transect and its vicinity of the watercourse, especially SMC in the soil layer of 100–260 cm increased significantly with a significant rise of GWD and reached maximum values at a GWD of about 4 m. Plant coverage and species diversity significantly improved with increases in SMC in the soil layer of 100–260 cm, both of them approached the maximum values and 92.3% of major plant species were able to grow when SMC was > 10%. To restore the ecosystem of desert riparian forest along the Lower Tarim River, the GWD must be maintained at < 4 m in the vicinity of the watercourse and at about 4 m for the rest of this arid region.  相似文献   

贵州秋绵雨的气候特征及异常成因浅析          下载免费PDF全文

许丹  任曼琳  张东海  严小冬 《中低纬山地气象》2022,46(4):1-8

利用贵州省83个气象观测站点1961—2021年逐日降水数据,定义贵州省单站秋绵雨过程,构建了综合考虑秋绵雨最长时段日数、其余时段累计日数、9—10月雨量占年雨量比例的秋绵雨综合强度评估指标,通过小波分析、突变分析、合成分析、相关分析等方法,对贵州秋绵雨的时空特征及其与北半球500 hPa高度场、全球海温场的关系进行了研究。结果表明：秋绵雨指数大致呈东北—西南向的条带状分布,自西北部向东南部递减;秋绵雨指数年际波动大,近61 a来以0.064/10a的速率呈下降趋势;秋绵雨指数EOF分析第1模态空间型表现为全区一致分布型,是贵州秋绵雨气候变率的主模态;贵州省秋绵雨存在2~4 a的年际变化周期;1997年为贵州秋绵雨突变点;重秋绵雨年500 hPa高度场欧亚大陆上空位势高度距平呈“北正南负”的距平分布,有利于北方冷空气南下,850 hPa距平风场南海及其周边地区为显著的反气旋性环流,加强了西南暖湿气流的输送;ENSO对贵州秋绵雨的影响是非对称的,当前期8月热带东太平洋偏暖、热带西太平洋偏冷时,对应El Niño年贵州秋绵雨偏重。  相似文献   

宁夏固原炭山地区中侏罗世沉积地质特征及其意义     

褚小东  郑毅  张鹏川  张晓东  何伟 《中国煤炭地质》2014,(5):9-13

炭山地区位于鄂尔多斯盆地西缘南部,区内含煤地层延安组厚度大,煤层发育;煤层具有镜质组含量低,惰质组含量高的特征。通过对该区构造、沉积地层和煤岩特征分析研究,并与邻近的六盘山盆地、鄂尔多斯盆地南部地区进行对比,认为炭山地区煤系地层主要为网状河道的冲积平原沉积环境和沼泽环境形成,早期存在的浅湖相沉积;说明与鄂尔多斯盆地南缘连通,是同处在鄂尔多斯盆地残延克拉通内的叠合盆地,但沉积了相对周边地区较厚的延安组,形成的煤层层数多,单层厚度小;结合该地区的构造背景,推断炭山地区是处在鄂尔多斯盆地残延克拉通内叠合盆地基础上的断陷盆地。在清水河大断裂和青铜峡—固原大断裂之间炭山地区以外的区域,与炭山地区具有相同的沉积环境和构造背景,推断应具有找煤前景。  相似文献   

新冠疫情防控措施对新疆地区地球背景噪声影响分析     

邓明文  李晓东  张森  徐小明  马建 《大地测量与地球动力学》2021,41(9):985-990

2020年7月中旬至8月下旬,新疆地区采取疫情防控措施。选取2020-06~2020-09新疆台网28个宽频带数字地震计的波形数据,获取相应的PSD（功率谱密度）和PDF（概率密度函数）,统计不同频段PSD值分布情况,分析疫情期间新疆地区噪声水平变化特征。结果显示,受新冠疫情的影响,乌鲁木齐地区高频段（2~20 Hz）噪声水平下降4.5%,其他地区也出现不同程度的降低,主要影响因素为人类活动的持续减少。同时,这种噪声减弱现象也由地表传达到地下。  相似文献   

Modeling the climatic effects of urbanization in the Beijing–Tianjin–Hebei metropolitan area     

Mingna Wang  Xuezhen Zhang  Xiaodong Yan 《Theoretical and Applied Climatology》2013,113(3-4):377-385

In this analysis, the weather research and forecasting model coupled with a single-layer urban canopy model is used to simulate the climatic impacts of urbanization in the Beijing–Tianjin–Hebei metropolitan area, which has experienced significant expansion in its urban areas. Two cases examining current landscapes and the sensitivity test of urban areas replaced by cropland have been carried out to explore the changes in the surface air and atmospheric boundary structure. The impact of urbanization on annual mean surface air temperature has been found to be more than 1 °C in urban areas, and the maximum difference is almost 2 °C. The change in near-surface level temperature is most pronounced in winter, but the area influenced by urbanization is slightly larger in summer. The annual mean water vapor mixing ratio and wind speed are both reduced in the urban area. The effect of urbanization can only heat the temperature inside the urban boundary layer, below 850 hPa. The modeling results also indicate that the underlying surface thermal forces induced by the “urban heat island” effect enhance vertical air movement and engenders a convergence zone over urban areas. The convergence at low level together with the moisture increases in the layer between 850 and 700 hPa triggered the increase of convective precipitation.  相似文献