昆仑山提孜那甫河流域2012-2016年近地表气温时空分布特征          下载免费PDF全文

孙从建  李伟  陈伟  张子宇  陈若霞 《干旱区地理》2019,42(3):459-468

基于典型高寒内陆河——提孜那甫河流域的6个不同海拔自设气象站的2012—2016年气温数据,分析了该地区不同海拔区域近地表气温的时间变化特征和空间变异特征。结果表明：（1） 低、中、高山区均温均可被sine函数高度拟合（R²>87%）,且随海拔增高气温波动减弱,时间变化延迟,气温变幅差异减小。（2） 日均温与月均温最低值出现月份不同步,且这一情况在海拔相对较高区更易出现。（3） 年内尺度不同区域气温空间差异：D1区（麻扎—库地）在秋、冬季最大;D3区（库地达坂—西合休）在春、夏、秋最小;D4区（西合休/库地达坂—莫木克）在夏季最大,冬季最小;D5区（莫木克—江卡）在春季最大,相关分析结果表明：气温空间分异受海拔影响大。研究结果将对提高高寒山区气候特征认知及改善冰雪水循环模拟具有重要促进意义。  相似文献   

Research and development on foam breaking and recycling technology in air-foam drilling   总被引：1，自引：0，他引：1       下载免费PDF全文

CAO Pinlu  ZHANG Jincheng  WU Xia  HUANG Jinyun 《世界地质(英文版)》2009,12(4):204-209

In recent years, air-foam combining the advantages of both liquid and air drilling has been utilized as a drilling medium. Air-foam drilling has proved its efficiency in numerous situations where serious problems were encountered, such as in fractured formations and depleted or high permeable zones. However, the major disadvantage of air-foam drilling system is that the foam can only be used once, so that an extremely large pit is required to contain the foam to allow sufficient room for cuttings and for the foam to dissipate. Moreover, it needs enormous volume prepared, consuming abundance of water and ingredient additives, which results in the high cost of foam drilling. The recycling foam fluid by using foam breaking technology is the only effective method to solve these problems associated with the known foam drilling. Various types of equipment and technique have been employed to suppress foam formation in biological and process equipment in foam drilling. The study described various methods of foam breaking technology, and the trend of the foam breaking technology for foam drilling is discussed.  相似文献   

自然界中磷循环研究的一些新动向综述   总被引：3，自引：0，他引：3  

许文娟 《化工矿产地质》1999,21(4):238-244

磷在人及生物生长发育过程中具有重要作用。它同时又是造成环境污染的一种成分。近年来国外学者在如何提高磷的利用效率、减少磷在生物体循环中造成的污染及磷的回收等方面进行了有益的探索 ,值得借鉴。  相似文献   

Simulation Study on Precipitation Recycling Ratio in the Tibetan Plateau from 1982 to 2005     

Hongwen Zhang  Yu Xu  Yanhong Gao 《地球科学进展》2020,35(3):297-307

A dynamical downscaling approach using a regional climate model WRF (Weather Research and Forecasting Model Vision 3.5) driven by a global climate model CCSM4 (The Community Climate System Model Version 4) was adopted, and the downscaling results for the historical period (1982-2005) were evaluated for annual mean precipitation rate and evaporation rate over the Tibetan Plateau (TP). Furthermore, the spatial distribution and seasonal variation characteristics of Precipitation Recycling Ratio (PRR) simulated by CCSM4 and WRF were analyzed with the QIBT (Quasi-isentropic Back-trajectory method). The results show that the historical spatial distributions of annual mean precipitation rate and evaporation rate over the TP were found to better reproduce in the dynamical downscaling modeling compared to its coarse-resolution forcing. The PRR of the TP is 32% simulated by WRF, with a higher PRR in the wet season and a lower PRR in the dry season for the river basins in the northern TP, but the opposite seasonal variation was found for the river basins in the southern TP. In addition, the different land covers over the TP are more precisely represented in the WRF model, the PRR of grassland, shrubland and sparsely vegetation is higher than that of other land cover types.  相似文献   

循环经济又好又快促进区域持续发展   总被引：1，自引：0，他引：1  

陈述彭 《地球信息科学学报》2007,9(1):3-9,2,137

循环经济是一种区域可持续发展的生态经济,也是我国全面建设小康社会和加快推进现代化发展阶段的一种新“社会-经济”模式。本文探讨了对循环经济的理念与共识,及其发展基础。同时,以上海、北京等大城市开始萌发的循环经济新模式,评述国内外对循环经济普及开发的案例。指出循环经济是推进区域经济可持续发展,保护资源与环境的重要战略之一。  相似文献   

"绿岛模式"研究--一个循环农业企业案例分析   总被引：7，自引：0，他引：7  

肖玲  林琳 《地理科学》2006,26(1):107-110

指出潮州市绿岛生态农业有限公司通过先后实施“果林开发”战略、“种养结合”战略和“旅游带动”战略,经历了“绿岛名、优、稀水果产业基地”、“绿岛猪—沼—果生态农业生产基地”和“绿岛循环农业生产基地”三个阶段的发展,形成了“绿岛模式”。认为“绿岛模式”是基于循环经济理念构建的以旅游业为龙头的循环农业生产系统,在形态上表现为以生态农业旅游区为载体的循环农业生产基地,是一种资源节约型农业企业模式,属于先进的现代农业企业模式之一。  相似文献   

俯冲物质深地幔循环——地球动力学研究的一个新方向   总被引：1，自引：0，他引：1  

杨经绥  连东洋  吴魏伟  芮会超 《地质学报》2021,95(1):42-63

地球上发生的各种地壳运动,大规模的火山喷发,不同深度不同规模的地震活动,规模宏大的山脉和高原的形成,以及地球历史上发生的大陆漂移运动,都被认为与板块构造活动密切相关.但这些运动的动力源究竟来自何方?如何去发现和证明它们的存在以及从理论上去认识和解释,是当今地球科学面临的巨大挑战,也是今后很长一段时间内地球科学的前沿和热...  相似文献   

A visage of early Paleozoic Japan: Geotectonic and paleobiogeographical significance of Greater South China     

Yukio Isozaki 《Island Arc》2019,28(3)

The current state of knowledge on the early Paleozoic evolution of Japan is reviewed. Although early Paleozoic Japan marked the foundation of long‐lasting subduction‐related orogenic growth throughout the Phanerozoic, details of this have not been fully revealed. Nevertheless, U‐Pb dating of zircons both in Paleozoic granitoids and sandstones is revealing several new aspects of early Paleozoic Japan. The timing of the major tectonic change, from a passive continental margin setting (Stage I) to an active one (Stage II), was constrained to the Cambrian by identifying the oldest arc granitoid, high‐P/T blueschist, and terrigenous clastics of arc‐related basins. Ages of recycled zircons in granitoids and sandstones provided critical information on the homeland of Japan, i.e. the continental margin along which proto‐Japan began to grow. The early Paleozoic continental margin that hosted the development of an arc‐trench system in proto‐Japan had cratonic basement composed mostly of Proterozoic crust with a minor Archean component. The predominant occurrence of Neoproterozoic zircons in Paleozoic rocks, as xenocrysts in arc granitoids and also as detrital grains in terrigenous clastics, indicates that the relevant continental block was a part of South China, probably forming a northeastern segment of Greater South China (GSC) together with the Khanka/Jiamsi/Bureya mega‐block in Far East Asia. GSC was probably twice as large as the present conterminous South China on mainland Asia. Paleozoic Japan formed a segment of a mature arc‐trench system along the Pacific side of GSC, where the N–S‐trending Pacific‐rim orogenic belt (Nipponides) developed with an almost perpendicular relationship with the E–W‐trending Central Asian orogenic belt. The faunal characteristics of the Permian marine fauna in Japan, both with the Tethyan and Boreal elements, can be better explained than before in good accordance with the relative position of GSC with respect to the North China block during the late Paleozoic.  相似文献   

浅水湖泊湖泛(黑水团)中的微生物生态学研究进展   总被引：5，自引：5，他引：0  

邢鹏  胡万婷  吴瑜凡  吴庆龙 《湖泊科学》2015,27(4):567-574

"湖泛"是指湖泊水体中(包括沉积物)富含大量藻源性(或草源性)的生物质,在微生物的分解作用下,大量消耗氧气,出现厌氧分解,微生物在还原条件下,促进许多"黑臭"物质的形成,进而影响水质和湖泊生态系统结构与功能乃至造成环境灾难.与湖泛发生时的环境特征(如低溶解氧,低p H,高有机质,高总磷、总氮)相对应的是其简化的食物网结构和特殊的微生物类群.本文将主要针对湖泛中的微生物群落及其在物质循环中的作用展开综述.研究显示湖泛水体中主要微生物类群,如真菌、细菌厚壁菌门的梭菌以及产甲烷古菌等,在有机质的快速分解和厌氧矿化过程中发挥着重要作用;沉积物中主要的微生物功能群,如硫酸盐还原细菌、铁还原细菌、甲烷厌氧氧化菌和反硝化细菌等,是湖泛致黑物质形成的关键.缺氧及厌氧条件下碳、硫和铁等元素生物地球化学过程的相互关联以及多种微生物之间形成的互营共生可能是湖泛过程中功能微生物的重要特征.湖泛中微生物功能的进一步研究,亟需借鉴海洋低氧区及深海沉积物的经验,引用先进研究手段,提出可靠的生物地球化学证据.浅水湖泊湖泛(黑水团)中的微生物生态学探索将有助于从机理上揭示湖泛黑臭的成因.  相似文献   

The Situation with College Express Packaging Waste and Recycling Recommendations—Taking the Graduate School of the Chinese Academy of Social Sciences as an Example     

ZHANG Wenjing 《资源与生态学报(英文版)》2019,10(5):530-536

Questionnaires and interviews are employed in this paper to investigate and analyze the situation with respect to express packaging waste at the Graduate School of the Chinese Academy of Social Sciences (GCASS). The survey results show that: (1) the campus receives a large number of express packages and there is, in turn, a considerable amount of packaging waste; (2) there are four main types of express packaging materials: paper packaging, plastic bags, wrapping tapes and package fillers; (3) neither the students nor the school perform well in the recycling of express packaging waste; (4) the samples investigated in this paper can be divided into four categories by cluster analysis, and the author infers from this that the colleges and universities with a large proportion of female students should pay more attention to the issue of recycling of express packaging waste. Several suggestions are presented based on the research results: (1) establishing a campus waste recycling system is the most efficient way to solve the problem of express packaging waste at GCASS; (2) we should advocate for green packaging and manage it from the source of waste generation because most of the express packaging material does not easily degrade naturally, and this represents a huge hidden danger to human health and the environment; (3) the school should cultivate student awareness of environmental protection. If education and penalties are implemented together, the recovery system will run better.  相似文献