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1. chinaXiv:202110.00045 [pdf]

2003—2018 年中国地表温度年最大值的时空分布及变化特征

王丽平
Subjects: Geosciences >> Atmospheric Sciences

中国幅员辽阔、气候差异大、人口众多,在全球气候变化背景下研究中国的气候变化对维 护中国乃至世界的粮食安全以及社会经济持续稳定发展具有十分重要的意义。地表温度最大值 可避免云雨天气对热红外遥感获取地表温度准确数据的干扰,且年变化较为稳定,但对重大土地 利用转移、干旱热浪等高度敏锐。基于 2003—2018 年 MODIS(Moderate resolution imaging spectrora? diometer)地表温度产品,采用气候倾向率、线性相关系数等研究方法分析了中国地表温度年最大 值的时空分布及变化特征。结果表明:(1)中国地表温度年最大值呈现北高南低的空间分布特征, 中国地表温度年最大值的最高值位于新疆吐鲁番盆地。(2)地表温度年最大值的空间分布按中国 气候区划分区分析表明,温带大陆性气候区地表温度年最大值最高,温带季风气候区的值较高,高 原山地气候区、亚热带季风气候区、热带季风气候区的值较低,地表温度年最大值的空间分布格局 与地表覆盖类型相关。(3)2003—2018 年,中国地表温度年最大值的时间变化特征总体表现为微弱 降温趋势,气候倾向率为-0.06 K·(10a)-1,降温区域占全国总面积的 50.45%。(4)气候倾向率在空间 上表现为西高东低,西部升温趋势比东部更加明显。部分区域表现为显著降温趋势,如北方中部、 华南区域、塔里木盆地边缘等,这些区域的降温与植被覆盖变化有关。

submitted time 2021-10-10 From cooperative journals:《干旱区地理》 Hits110Downloads60 Comment 0

2. chinaXiv:202108.00021 [pdf]

自动土壤水分观测资料异常数据检测方法

李翠娜; 刘天琦
Subjects: Geosciences >> Geochemistry

针对全国自动土壤水分实时小时观测资料,结合仪器标定方法、土壤水文物理常数等因 素,研究土壤水分固有变化特征,分析异常数据误差来源和阈值判定,利用频率检测、界限值检测、 无降水突变检测、异常峰值检测、恒值检测五类方法对土壤水分观测资料进行质量控制实验和检验。结果表明:(1)自动土壤水分异常数据主要分为:粗大值、突变、异常峰值和僵值,主要由仪器 失灵、土壤水文物理常数测定不准、传感器标校不合理等原因引起。(2)频率检测可有效检出因仪器故障引起的错误数据。目前该方法已应用于综合气象观测数据质量控制业务系统,用于开展全国实时自动土壤水分小时数据的质量控制和质量评估。

submitted time 2021-08-02 From cooperative journals:《干旱区地理》 Hits307Downloads165 Comment 0

3. chinaXiv:202108.00037 [pdf]

基于微波辐射计的宁夏六盘山西侧大气水汽变化特征

林彤; 桑建人
Subjects: Geosciences >> Atmospheric Sciences

采用隆德气象站 2 a 德制微波辐射计与同期 1 h 降水量资料,利用统计法分析了六盘山脉西 侧大气水汽含量以及云液态水含量的时间分布特征,并分析了92 次不同降水性质、不同降水量级 的降水个例,得到降水前跃增时间的变化特征。剔除降水背景结果统计表明:(1)六盘山西侧大气 水汽含量和云液态水含量有明显的季节变化,其中夏季是大气水汽含量最多的季节,平均为 23.44 mm,占年均水汽含量的 47.7%。(2)大气水汽含量和云液态水含量日变化呈一谷一峰分布,春、夏、 秋三季均在午后出现最大峰值,冬季在 11:00出现峰值;大气水汽含量低值区春、夏、秋季出现在日 出前后,冬季出现在 22:00。(3)87.0%的降水个例在降水发生之前大气水汽含量都在 12.00 mm 以 上,且其值随着降水的量级增大而增大。(4)降水前云液态水含量发生明显跃增现象,春、夏季表现 强,根据降水性质及降水量级不同,降水前跃增时间也不同。研究结论对把握人影作业时机具有 一定的参考价值。

submitted time 2021-08-01 From cooperative journals:《干旱区地理》 Hits140Downloads87 Comment 0

4. chinaXiv:202106.00051 [pdf]

西藏地区潜在蒸散量时空格局特征及影响因素研究

史继清; 豆永丽
Subjects: Geosciences >> Geography

利用1981—2018年西藏地区38个气象站点的逐日气象观测资料,采用联合国粮农组织Food and Agricul?ture Organization of the United Nations(FAO)推荐的Penman-Monteith公式估算了各站点的潜在蒸散量(ET0),分别从趋势性、突变性以及周期性分析了ET0的时空变化格局及其影响因素。结果表明:在时间尺度上,西藏地区ET0均表现出先“下降”后“升高”的趋势,其中“下降”阶段ET0整体呈显著的降低趋势(除冬季外),“升高”阶段呈显著的增加趋势(除春、夏季)。在空间尺度上,春、夏季表现出减少和秋冬季、年际表现出增加的趋势。发生突变的站点主要分布在中南部和东北部区域,时间集中在20世纪80年代;年均ET0变化的第一主周期为33 a(2013年)。此外,平均风速和相对湿度是影响年及季节ET0的主要因素,同时平均风速、相对湿度和最高温度对ET0的影响趋势具有很强的一致性。

submitted time 2021-06-13 From cooperative journals:《干旱区研究》 Hits2333Downloads259 Comment 0

5. chinaXiv:202105.00044 [pdf]

2015年11月4日太阳射电爆发干扰导航信号事件中的X-ray先兆分析

董亮; 闫小娟; 黄文耿; 李攀; 于超; 高冠男; 阿尔察; 沈发新; 郭少杰
Subjects: Astronomy >> Astrophysical processes

太阳射电爆发是无线通信特别是卫星导航通信的潜在影响因素之一。2015年11月4日的太阳射电爆发事件在1415MHz点频上的流量达到了峰值5800SFU(Solar Flux Unit),位于日下点的欧洲GPS系统和瑞典的航空导航系统均受到了影响。本文分析了该次事件产生源活动区的X-ray流量变化与射电流量变化之间的时间前后关系;通过比对,X射线的流量抬升时间较之于射电阈值具有30分钟的提前量;随后本文讨论了该提前量之间的物理背景,即软硬X射线分别对应了热电子和非热电子辐射,而非热电子是产生能够造成该类空间天气事件射电爆发的物理条件,X射线由软转硬过程中流量的抬升变化,正好为进一步防控该类空间天气事件提供了一种有效的手段。

submitted time 2021-05-08 From cooperative journals:《天文研究与技术》 Hits1886Downloads379 Comment 0

6. chinaXiv:202101.00022 [pdf]

新疆沙产业状况与水资源承载力研究

刘洪霞
Subjects: Geosciences >> Hydrology

采用 2000、2005、2010、2015 年 4 期土地利用/土地覆盖遥感解译数据以及新疆水资源公报 和统计年鉴资料,旨在评价新疆沙产业与水资源承载力状况。通过计算未利用土地转化成农地、 林地、草地的数量,分析 16 a 来新疆沙产业发展状况,结合水足迹模型和区域水资源承载力评价指 标,计算新疆 2000—2015 年水足迹,对区域水资源承载力进行评价。结果表明:(1)2000—2015 年 间,随着新疆人口增长和经济的发展,新疆沙产业发展迅速,部分沙地、戈壁等未利用土地和草地 被开发成耕地、林地、工矿和城镇及农村居民用地。(2)新疆水足迹整体呈上升趋势,水足迹以消费 农产品水足迹占主体,且消费农产品水足迹量快速增加,主要原因是新疆地区大力发展沙产业,利 用未利用土地、草地进行植物、沙生药材种植。(3)新疆人均水足迹、水资源压力指数、水足迹效益 指标呈现增加趋势,但数值明显低于我国人均水平。新疆社会经济发展总体趋势向好,但水资源 利用方式仍然比较粗放,水资源未得到合理开发。因此,新疆应采取优化产业结构、调整农作物种 植比例和用水结构,以增大水资源所支撑的沙产业发展规模,研究可为区域产业结构及消费模式 调整提供依据。

submitted time 2021-01-06 From cooperative journals:《干旱区地理》 Hits648Downloads398 Comment 0

7. chinaXiv:202010.00045 [pdf]

湘西地区祛风除湿药用植物的资源调查及可持续利用建议

贺建武; 姚佩双; 李珍珍; 卜丽; 曾正媛; 龙春林
Subjects: Biology >> Botany >> Applied botany

湘西地区祛风除湿的医药传统知识历史悠久,但相关药用植物的资源本底和传统知识现状还不够清楚。该文基于民族植物学调查方法,对湘西地区祛风除湿药用植物的组成、相关传统知识、定量评价、实际估价和在《湖南省中药材标准》(2009年版)收录情况等方面进行了系统梳理,并就该类资源的可持续利用提出了相关建议。结果表明:湘西地区目前利用的祛风除湿药用植物共有48科65属71种,以毛茛科(Ranunculaceae) 和五加科(Araliaceae) 居多;根、全株、茎(藤)为主要利用部位;生活型主要是草本、藤本和灌木,乔木较少;与药用植物相关的传统知识在代际传播方面存在不确定性;寻骨风(Aristolochia mollissima Hance)、威灵仙(Clematis chinensis Osbeck) 和广防风[Anisomeles indica (L.) Kuntze]显示出最高的知识一致性水平,是本次调查中3种最常用的祛风除湿药用植物;当地药用植物的本地价格受市场影响较小,总体维持在较为平稳的水平,且缺乏对药材消费需求的了解;有25种祛风除湿药用植物在《湖南省中药材标准》(2009年版)收录的功能与主治为祛风除湿、关节痹痛、风湿等。随着现阶段我国资源立法的不断完善,建议对湘西地区祛风除湿药用植物相关传统知识加强保护,提高该类资源的生物多样性和可持续利用水平;并充分利用多学科交叉知识和技术手段,加强区域内传统医药资源的发掘和创新,让湘西丰富的药用植物资源更好地为人类健康做出贡献。

submitted time 2020-10-20 From cooperative journals:《广西植物》 Hits5622Downloads1019 Comment 0

8. chinaXiv:202010.00038 [pdf]

Glacier variations and their response to climate change in an arid inland river basin of Northwest China

ZHOU,Zuhao; HAN,Ning; LIU,Jiajia; YAN,Ziqi; XU,Chongyu; CAI,Jingya; SHANG,Yizi; ZHU,Jiasong
Subjects: Geosciences >> History of Geosciences

Glaciers are a critical freshwater resource of river recharge in arid areas around the world. In recent decades, glaciers have shown evidence of retreat due to climate change, and the accelerated ablation of glaciers and associated impacts on water resources have received widespread attention. Glacier variations result from climate change, so they can serve as an indicator of climate change. Considering the climatic differences in different elevation ranges, it is worthwhile to explore whether different responses exist between glacier area and air temperature in each elevation zone. In this study, we selected a typical arid inland river basin (Sugan Lake Basin) in the western Qilian Mountains of Northwest China to analyze the glacier variations and their response to climate change. The glacier area data from 1989 to 2016 were delineated using Landsat Thematic Mapper (TM), Enhanced TM+ (ETM+) and Operational Land Imager (OLI) images. We compared the relationships between glacier area and air temperature at seven meteorological stations in the glacier-covered areas and in the Sugan Lake Basin, and further analyzed the relationship between glacier area and mean air temperature of the glacier surfaces in July–August in the elevation range of 4700–5500 m a.s.l. by the linear regression method and correlation analysis. In addition, based on the linear regression relationship established between glacier area and air temperature in each elevation zone, we predicted glacier areas under future climate scenarios during the periods of 2046–2065 and 2081–2100. The results indicate that the glaciers experienced a remarkable shrinkage from 1989 to 2016 with a shrinkage rate of –1.61 km2/a (–0.5%/a), and the rising temperature is the decisive factor dominating glacial retreat; there is a significant negative linear correlation between glacier area and mean air temperature of the glacier surfaces in July–August in each elevation zone from 1989 to 2016. The variations in glaciers are far less sensitive to changes in precipitation than to changes in air temperature. Due to the influence of climate and topographic conditions, the distribution of glacier area and the rate of glacier ablation first increased and then decreased in different elevation zones. The trend in glacier shrinkage will continue because air temperature will continue to increase in the future, and the result of glacier retreat in each elevation zone will be slightly slower than that in the entire study area. Quantitative glacier research can more accurately reflect the response of glacier variations to climate change, and the regression relationship can be used to predict the areas of glaciers under future climate scenarios. These conclusions can offer effective references for assessing glacier variations and their response to climate change in arid inland river basins in Northwest China as well as other similar regions in the world.

submitted time 2020-10-20 From cooperative journals:《Journal of Arid Land》 Hits781Downloads451 Comment 0

9. chinaXiv:202008.00029 [pdf]

湖南江华瑶族药浴植物的民族植物学研究

方琼; ?胡仁传; 程卓; ?罗斌圣; 江霞; 龙春林
Subjects: Biology >> Botany >> Applied botany

瑶族民间药浴历史悠久,是重要的疾病预防和治疗手段,是我国重要的非物质文化遗产。江华瑶族自治县药浴植物丰富,药浴配伍独具当地特色。本研究采用民族植物学方法对湖南江华瑶族自治县瑶族传统利用的药浴植物进行了调查。共收集整理了152种药浴植物,隶属于70科125属,记录了其瑶名、学名、入药部位以及功能主治等。并调查记录了部分常用药浴与产后药浴植物配伍。结果表明:江华瑶族药浴植物中草本植物占明显优势,且多为全草入药,主要用于治疗风湿关节炎、跌打损伤、妇科病以及皮肤病等,常用的药浴植物多为祛风除湿的“风药”;同时,通过实地调查和访问调查发现,珍贵药浴植物种群规模因过度采挖和生境破坏而减小;对比了广西、云南、湖南等地区瑶族药浴植物的异同,探讨其背后的相关性和原因。作为非物质文化遗产的瑶族药浴面临诸多方面的威胁,其内部科学性仍有待探究,需进一步加强综合研究与合作,为其保护、传承和发扬提供保障。

submitted time 2020-08-02 From cooperative journals:《广西植物》 Hits1337Downloads820 Comment 0

10. chinaXiv:202006.00223 [pdf]

Market opportunities do not explain the ability of herders to meet livelihood objectives over winter on the Mongolian Plateau

BAI Haihua; YIN Yanting; Jane ADDISON; HOU Yulu; WANG Linhe; HOU Xiangyang
Subjects: Geosciences >> History of Geosciences

Drylands under pastoral land use are considered one of the most vulnerable social-ecological systems to global climate change, but the herders' abilities to adapt to the different extreme weather events have received little attention in the drylands. Herders on the Mongolian Plateau (MP; including Inner Mongolia Autonomous Region of China and Mongolia), have had a long history of adapting climatic variability and extreme weather events. However, it is unclear how changes such as increased levels of infrastructure and market integration affect the ability of herders to achieve the key livelihood objectives: the minimisation of the death and abortion rates of livestock in the winter. Here, we used remotely sensed and household survey data to map, model and explore the climate exposure and sensitivity of herders in the settled area (Inner Mongolia of China) and nomadic area (Mongolia) in the winter of 2012–2013. We aimed to quantify the multi-scaled characteristics of both climate exposure and sensitivity through the lens of key adaptive strategies utilized by herders. Our results showed that the higher levels of infrastructure and market integration, and the lower levels of remoteness on the MP did not increase the herders' ability to achieve the key livelihood objectives. Our results also suggested that exposure to the snow that is comparatively greater than the long-term average (cumulative exposure) may be more important in determining the social-ecological vulnerability than absolute exposure. We suggested that neither the risk management strategies available to these herders, nor the demographic variables, could compensate for the mode of production governing the pastoral systems. Our study could provide further evidence for the complex and scaled nature of climate exposure and sensitivity, and the results imply that any analysis of the relationship among exposure, sensitivity and vulnerability of pastoral households to climate change in the drylands will require a multi-scaled and interdisciplinary approach.

submitted time 2020-06-22 From cooperative journals:《Journal of Arid Land》 Hits12758Downloads1163 Comment 0

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