Comprehensive applicability evaluation of four precipitation products at multiple spatiotemporal scales in Northwest China

Precipitation plays a crucial role in the water cycle of Northwest China.Obtaining accurate precipitation data is crucial for regional water resource management,hydrological forecasting,flood control and drought relief.Currently,the applicability of multi-source precipitation products for long time series in Northwest China has not been thoroughly evaluated.In this study,precipitation data from 183 meteorological stations in Northwest China from 1979 to 2020 were selected to assess the regional applicability of four precipitation products(the fifth generation of European Centre for Medium-Range Weather Forecasts(ECMWF)atmospheric reanalysis of the global climate(ERA5),Global Precipitation Climatology Centre(GPCC),Climatic Research Unit gridded Time Series Version 4.07(CRU TS v4.07,hereafter CRU),and Tropical Rainfall Measuring Mission(TRMM))based on the following statistical indicators:correlation coefficient,root mean square error(RMSE),relative bias(RB),mean absolute error(MAE),probability of detection(POD),false alarm ratio(FAR),and equitable threat score(ETS).The results showed that precipitation in Northwest China was generally high in the east and low in the west,and exhibited an increasing trend from 1979 to 2020.Compared with the station observations,ERA5 showed a larger spatial distribution difference than the other products.The overall overestimation of multi-year average precipitation was approximately 200.00 mm and the degree of overestimation increased with increasing precipitation intensity.The multi-year average precipitation of GPCC and CRU was relatively close to that of station observations.The trend of annual precipitation of TRMM was overestimated in high-altitude regions and the eastern part of Lanzhou with more precipitation.At the monthly scale,GPCC performed well but underestimated precipitation in the Tarim Basin(RB=-4.11%),while ERA5 and TRMM exhibited poor accuracy in high-altitude regions.ERA5 had a large bias(RB≥120.00%)in winter months and a strong dispersion(RMSE≥35.00 mm)in summer months.TRMM showed a relatively low correlation with station observations in winter months(correlation coefficients≤0.70).The capture performance analysis showed that ERA5,GPCC,and TRMM had lower POD and ETS values and higher FAR values in Northwest China as the precipitation intensity increased.ERA5 showed a high capture performance for small precipitation events and a slower decreasing trend of POD as the precipitation intensity increased.GPCC had the lowest FAR values.TRMM was statistically ineffective for predicting the occurrence of daily precipitation events.The findings provide a reference for data users to select appropriate datasets in Northwest China and for data developers to develop new precipitation products in the future.

Overview of the Tourism Land Use Researches in China and Abroad

Both domestic and overseas researches in tourism land use have been analyzed,summarized and commented in detail,and the research characteristics have been compared respectively.

The Islamic Studies in China-Research in Political and Social Fields

In the research of political and social fields,modern Islamic politics has evolved into three schools of nationalism,modernism and fundamentalism in the 20th century.The research in the field of contemporary Islam involves different countries,nationalities and different economic and political conditions.It is not only the research field of religion,but also has the characteristics of interdisciplinary academic frontier.From the perspective of academic research,these trends have attracted the attention and research of scholars inside and outside the church on Islamic political and social issues.Recently,there have been many problems related to Islam and the current international political life,as well as the research results of Islamic social thoughts and social movements.

Research Progress in the Petroleum and Natural Gas Geological Theory of China

The Chinese landmass, as a composite region, consists of multiple small continental blocks, such as Sino-Korea, Yangtze, Tarim, etc., and orogenic belts. Because of its distinctive tectono-sedimentary evolution, China＇s oil/gas-bearing regions differ remarkably from that elsewhere in the world. For instance, in comparison to the Middle East oil/gas-bearing regions which are characterized by Mesozoic-Cenozoic marine oil/gas-bearing beds, early oil and gas discoveries in China are distributed mainly in Mesozoic-Cenozoic continental sedimentary basins. Generation of oil from terrestrial organic matter, or terrestrial oil generation, and the formation of large oil/gas fields in continental sedimentary basins were previously the major characteristics of petroleum geology of China. However, in the past 20 years, a series of major oil and gas discoveries from marine strata have been made. Marine oil/gas fields in China are mainly distributed in the Tarim, Sichuan, and Ordos basins, which are tectonically stable and covered with Mesozoic-Cenozoic deposits. In these basins, hydrocarbon-bearing strata are of old age and the oil/gas fields are commonly deeply-buried. Cumulatively, 995 oil/gas fields have been found so far, making China the fourth largest oil-producing country and the sixth largest gas-producing country in the world. In terms of petroleum and natural gas geology, theories of hydrocarbon generation from continental strata, such as terrestrial oil generation and coal-generated hydrocarbons, etc., have been established. Significant progress has been made in research on the sequence stratigraphy of continental strata, formation mechanisms of ultra-deep clastic reservoirs, and hydrocarbon accumulation in the continental subtle reservoir. Regarding research on the marine petroleum geology of China, with respect to the major characteristics, such as deeply-buried reservoirs, old strata, and multiple phases of transformation, important advances have been made, in areas such as the multiple-elements of hydrocarbon supply, formation of reservoirs jointly controlled by deposition, tectonic activities, and diagenetic fluid-rock reactions, and oil/gas reservoirs formed through superimposed multi-stage hydrocarbon accumulation. As more and more unconventional hydrocarbon resources are discovered, unconventional oil and gas reservoirs are under study by Chinese petroleum geologists, who endeavor to come up with new discoveries on their formation mechanisms.

Identification and Evaluation of Low Resistivity Pay Zones by Well Logs and the Petrophysical Research in China

This paper presents an overview of petrophysical research and exploration achievements of low resistivity pay （LRP） zone by well logs in China. It includes geological characteristics and characteristics of well log response of the low resistivity pay zones discovered and evaluated in recent years, as well as the problems in recognizing and evaluating low resistivity pay zones by well logs. The research areas mainly include the Neogene formations in the Bohai Bay Basin, the Triassic formations in the northern Tarim Basin and the Cretaceous formations in the Junggar Basin, The petrophysical research concerning recognition and evaluation of the low resistivity pays, based on their genetic types, is introduced in this paper.

Perceptions of climate change in China:The research and policy connection

Global climate change has evolved from a scientific problem into an economic and political problem oI worlOwloe rater- est. National perspectives play a crucial role in addressing climate change. Mutual understanding of perspectives is nec- essary to result in rational policies and a consensus among stakeholders with divergent interests. Conceptual frameworks for understanding the problem of climate change in China, the largest developing country and the largest greenhouse gas emitter, are of great significance to national and international efforts to address the problems of climate change. Chinese perceptions of climate change as a sustainable development problem have recently been in tension with an emerging Western perspective that frames climate change as a security issue. This paper explores Chinese perceptions of climate change as expressed in recent governmental policy statements, public opinion surveys, and academic scholarship with a focus on publications in Chinese-language journals, often unfamiliar in the West. It looks at the relationship between Chinese research and policy and finds that the Chinese policy frame of climate change as a sustainable development problem draws from the body of domestic research and is reflective of the perspectives and multidisciplinary approach of Chinese researchers in areas of climate change.

Research Progress of the Mineralization of Carbonate-Hosted Pb-Zn Deposits in the Sichuan-Yunnan-Guizhou Pb-Zn Metallogenic Province, Southwest China

The Sichuan-Yunnan-Guizhou （SYG） Pb-Zn metallogenic province in the western Yangtze Block, is a key component of the low-temperature metallogenic domain in South China. In this area, more than 400 Pb-Zn deposits have been discovered, and the total proven reserves are up to 260 million tons with lead and zinc grade reaching 10%, even up to 30%.

Regulation on the Protection of Fossils Issued by the State Council of the People's Republic of China:Scientists' Researches Protected Legally—Further Explanation

With large-scale engineering projects being carried out in China, a large number of fossil localities have been discovered and excavated by responsible agencies, but still some important fossils of great value have been removed and smuggled into foreign countries. In the last three years, more than 1345 fossil specimens have been intercepted by Customs in Shenzhen, Shanghai, Tianjin, Beijing and elsewhere, and more than 5000 fossils, most of which are listed as key fossils,

On the 2002 U. S. Mid-Term Election Zhang Yanyu and Wang Wenfeng are both assistant research professors at the Division for American Studies in China Institute of Contemporary International Relations

The first mid-term election of the U. S. in the new century took place on November 5, 2002. One third of the senators from the 107th Congress (34 out of 100), all representatives (435), 36 state governors, and numerous local officials and legislators were to be elected or reelected. The resounding victory of the GOP in the congressional elections and the fact that the Democrats only got three more.

The Status and Trend of Research on Standards for Eoological Textile in China

The products of ecological textile have represented nowadays the new trend ofglobal consumption and production of textile while become an important means for some countries toutilize 'green barrier' as a limitation of import of textile products. Following the entrance ofChina into the WTO, the position of 'green barrier' becomes significantly important in the trade oftextile products. As China is a big country of textile production, speeding up the research onstandards for products of ecological textile, countering the latest situation appearing ininternational trade of textile, to take as quickly as possible responsive measures is a very urgentproblem in port, to enhancing the ability of international market competition and to promoting thestable development of foreign oriented economy.

THE PROGRESS OF PHYTOCHEMISTRY AND ITS CURRENT RESEARCH STATUS IN CHINA

It is of strategical significance to exploit new medicines with Chinese features and with their patented rights phytechemistry will have great prospects in this aspect. This article briefly introduces the main research fields on phytochemistry and their significance, the present research situation in China, and suggests some concrete proposals on the development of the discipline in China.

Research Progress on the Application of Magnesium Hydroxide in the Industrial Wastewater Treatment Filed

The research progress on the application of magnesium compounds (magnesium hydroxide,light calcined magnesia,magnesium chloride,sea water,brine,dry brine,etc.) which were represented by magnesium hydroxide in the wastewater treatment filed was comprehensively commentated.Meanwhile,the prospects of application were discussed.Considering the magnesium resources in China were characterized with rich classes,abundant reserves,vast distribution and high quality,it's important to make great efforts to research and exploit magnesium products,especially the exploitation of their meticulous use way.It had the practical significance for the sustainable development of economy in China.

Dynamic Game Research on Multiple Subjects in the Real Estate Market of China

In order to analyze the deep-routed reason for the failure of the real estate market regulation policy, this paper established an incomplete information tri-game model in which central government, local government and the real estate developer were chosen as three main research objects. Based on the analysis of their interest appeals under the assumption of rational economic man, we found that it was the difference of interest appeals of central and local governments as well as the real estate developers that caused the game among the three participants. This, however, led to the failure of the macro-control at last. Strengthening the supervision of central government and reducing its cost at the same time, what’s more, improving the efficiency of the supervision and increasing the punishment of the rent-seeking behavior between local government and the real estate developers will contribute to improve the implementation status of the regulation and control policy. We suggest the authorities improve the government political achievement appraisal system and reform the current system of benefits distribution;moreover, reform the existing regulatory system and strength the regulatory role of media and the third-party so as to promote the healthy development of the real estate market.

Preliminary research on sea-level changes of the South China coast since late Epipleistocene

Several views on sea-level changes of the South China coast are briefly introduced in this paper. On the basis of 236 samples whose ages are determined by 14C chronological method and their sites are corrected with ancient water depth and crustal deformation, a basic model about sea-level changes of the South China coast since late Epipleistocene is set up. This model basically accords with the general cognitions of predecessors, i. e. it not only represents the common characteristics of sea-level changes of the East China coast but has some features of the South China coast itself. In general, this model is relatively close to the Fairbridge's curve, indicating that the sea-level undulations exist since 6 ka ago but the ranges of undulations are slightly larger than those of Fairbridge's curve.

A Further Research on the Precambrian-Cambrian Boundary at Meishucun Section of Jinning, Yunnan, China

This paper gives a brief report on the latest results in litho-, bio-, and chrono-stratigraphy obtained fromthe authors' further research on the Meishucun section during 1987-1988. More attention was paid to the studyof the microtexture of Lapworthella and some new materials of trace fossils. Phycodes pendum Seilacher, animportant index for correlation, was also discovered in the Zhongyicun Member. In the Yu' anshan Membermany worms, medusas and arthropods of the Chengjiang fauna have been found by other workers. Asupplemental study was made on the fossil zones of the Meishucunian stage. Based on new isotopic data, theage of the Precambrian-Cambrian boundary should now be 597 Ma. It is further suggested that point 'B' re-mains as an optimum selection for defining the Precambrian-Cambrian boundary.

Test Research on the Characteristics of Pollution Boundary Layer in the River Outlet Area of Grand Liao River

By using the meteorological data in the pollution boundary layer which was observed in two ground observation sites:coast and land in the river outlet area of Grand Liao River during January-February in 2007,the daily change characteristics of pollute boundary layer in winter in the area were discussed. The results showed that the pollute boundary layer in the river outlet area of Grand Liao River was affected by the sea and land. In the certain weather condition,maybe the sea-land breeze appeared in the low altitude which was below 200 m in the coastal zone. The stability change in the different height in the coastal zone was more stable than in the land zone,and the wind field change in the area was mainly in 300 m low altitude. At night,the temperature inversion often appears in the area,and the thickness of temperature inversion layer is stably during 200-300 m. The thermal internal boundary layer penetrated deeply into the land about 10 km,and the height could reach 800 m. The atmospheric diffusion ability in the coastal area was weaker and stronger in the land area.

The status quo of China＇s urban wisdom pension research

AAs the traditional pension services in the development process of the technical level is lower, the service is difficult to meet the demand of the elderly, the development of pension services need to seek new breakthroughs. Therefore, this article will be sent to you by combing the current wisdom endowment of typical cases at home and abroad, analyzed the current status of wisdom endowment difference at home and abroad, sums up the problems of Chinese wisdom endowment, and put forward the intelligent pension services to fit the development of China＇s urban Suggestions and countermeasures, and prospects for the development of China＇s pension market to speculate.