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排序方式: 共有353条查询结果,搜索用时 15 毫秒
91.
The Chinese Carbon Dioxide Observation Satellite Mission(TanSat)is the third satellite for global CO2 monitoring and is capable of detecting weak solar-induced chlorophyll fluorescence(SIF)signals with its advanced technical characteristics.Based on the Institute of Atmospheric Physics Carbon Dioxide Retrieval Algorithm for Satellite Remote Sensing(IAPCAS)platform,we successfully retrieved the TanSat global SIF product spanning the period of March 2017 to February 2018 with a physically based algorithm.This paper introduces the new TanSat SIF dataset and shows the global seasonal SIF maps.A brief comparison between the IAPCAS TanSat SIF product and the data-driven SVD(singular value decomposition)SIF product is also performed for follow-up algorithm optimization.The comparative results show that there are regional biases between the two SIF datasets and the linear correlations between them are above 0.73 for all seasons.The future SIF data product applications and requirements for SIF space observation are discussed.  相似文献   
92.
Eutrophication in coastal area has become more and more serious and mariculture potential is a main cause.Although there are some quantitative research on nutrient loads in national and global perspective, the calculation method problems make the results controversial. In this paper, the farming activities are divided into fed culture types(include cage culture and pond culture) and extractive culture types(e.g. seaweed, filter-feeding shellfish culture). Based on the annual yield of China in 20...  相似文献   
93.
Based on the contents of six heavy metal elements in surface sediments from coastal areas of Fujian Province, the distribution characteristics and controlling factors of six heavy metals in a bay-island-estuary system(BIES) were studied. This paper focuses on the influence of the hydrodynamic environment, and systematically discusses how grain size compositions, chemical environment, tidal current, ocean circulation and human activities influence the distribution and transportation of the heavy ...  相似文献   
94.
Yi Liu  Yaoli Lei 《甘肃地质》2000,(2):114-115
The Silk Road is one of the most important cultural routes in human being history and it had survived abundant cultural heritages.Under the vision of culture integrity,the constitution of the Silk Road(Shaanxi section)heritage corridor should involve tangible and intangible heritage elements.It is necessary to recognize the relationship between tangible and intangible culture heritages in order to realize the reasonable conservation of the Silk Road.  相似文献   
95.
NEW MAGNETOSTRATIGRAPHIC AND SEDIMENTOLOGIC RESULTS FROM TERTIARY SEDIMENTS OF THE HOH XIL BASIN, NORTHERN QINGHAI-TIBET PLATEAU: IMPLICATIONS FOR THE CENOZOIC TECTONIC HISTORY OF THE TIBET PLATEAU  相似文献   
96.
FINITE STAIN MEASUREMENT AND SHORTENING ANALYSIS IN THE NORTHERN MARGIN OF QINGHAI—TIBET PLATEAU  相似文献   
97.
TECTONIC CHARACTERISTICS AND EVOLUTION OF THE QIANGTANG BASIN IN NORTHERN TIBET PLATEAU  相似文献   
98.
利用1998年10月3日北京天文台怀柔太阳观测站的高质量磁图,对给定的太阳宁静区两种不同极性的磁场进行了功率谱分析.结果表明,空间功率谱在超米粒和中米粒尺度具有明显的尖峰结构,这对应于空间周期性分布的网络和内网络磁结构.结果也显示出,超米粒边缘所包含的两种极性场中,其中的一种极性占优势.通过瞬态功率谱的分析,得出网络和内网络场寿命之间的比例关系,这一结果和其他学者得出的超米粒和中米粒对流寿命之间的关系相符.  相似文献   
99.
This study focuses on the Lower Yellow River(LYR), which has experienced continuous erosion since the operation of Xiaolangdi Reservoir in 1999, and its spatiotemporal variation process is complex. Based on the single-step mode of the Delayed Response Model(DRM), we proposed a calculation method for simulating the accumulated erosion and deposition volume in the LYR. The coefficient of determination R2 between the calculated and measured values from 2000 to 2020 is 0.99. Currently, th...  相似文献   
100.
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