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Zoning Evaluation of Hourly Precipitation in High-resolution Regional Numerical Models over Hainan Island
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作者 冯箫 吴俞 +1 位作者 杨薇 李勋 《Journal of Tropical Meteorology》 SCIE 2023年第4期460-472,共13页
This study assesses the performance of three high-resolution regional numerical models in predicting hourly rainfall over Hainan Island from April to October for the years from 2020 to 2022.The rainfall amount,frequen... This study assesses the performance of three high-resolution regional numerical models in predicting hourly rainfall over Hainan Island from April to October for the years from 2020 to 2022.The rainfall amount,frequency,intensity,duration,and diurnal cycle are examined through zoning evaluation.The results show that the China Meteor-ological Administration Guangdong Rapid Update Assimilation Numerical Forecast System(CMA-GD)tends to forecast a higher occurrence of light precipitation.It underestimates the late afternoon precipitation and the occurrence of short-duration events.The China Meteorological Administration Shanghai Numerical Forecast Model System(CMA-SH9)reproduces excessive precipitation at a higher frequency and intensity throughout the island.It overestimates rainfall during the late afternoon and midnight periods.The simulated most frequent peak times of rainfall in CMA-SH9 are 0-1 hour deviations from the observed data.The China Meteorological Administration Mesoscale Weather Numerical Forecasting System(CMA-MESO)displays a similar pattern to rainfall observations but fails to replicate reasonable structure and diurnal variation of frequency-intensity.It underestimates the occurrence of long-duration events and overestimates related rainfall amounts from midnight to early morning.Notably,significant discrepancies are observed in the predictions of the three models for areas with complex terrain,such as the central,southeastern,and southwestern regions of Hainan Island. 展开更多
关键词 hainan island hourly precipitation regional numerical model zoning evaluation
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Granite thermal reservoirs in Lingshui area of Hainan Island and their significance to geothermal resources,China
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作者 Xiaorui Yun Ying Zhang +2 位作者 Dingyong Liang Yanming Qu Haifeng Chen 《Energy Geoscience》 2023年第4期159-170,共12页
Hainan Island located at the southernmost tip of the continental crust of the South China Plate,has high terrestrial heat-flow values,widely-distributed hot springs,and rich geothermal resources.Intensified researches... Hainan Island located at the southernmost tip of the continental crust of the South China Plate,has high terrestrial heat-flow values,widely-distributed hot springs,and rich geothermal resources.Intensified researches on the origin and potentials of geothermal resources can promote Hainan Island's development into a clean energy island.To determine the geological conditions for the formation of geothermal resources in southern Hainan Island,we collected core samples of granites from the Baocheng batholith in southern Hainan Island and conducted systematic analysis in respect of petrology,geochronology,geochemistry,and petrophysical property.The results of this study are as follows.The Baocheng batholith in the southern Hainan Island has a crystallization age of 98.42±0.56 Ma,making it the product of magmatism in the early stage of the Late Cretaceous.It mainly consists of high-K calc-alkaline granites,which were intruded by intermediate-to-mafic veins.The Baocheng batholith has a high radioactive heat generation rate of 2.712-6.843μW/m^(3),with an average of 3.846μW/m^(3),a radioactive heat-flow value of 30.768 μW/m^(2)and a heat-flow contribution rate of 38.95%-43.95%.As shown by the results of their thermophysical property analysis,the granites have high thermal conductivity and can serve as highquality geothermal reservoirs.In combination with previous geological and geophysical data,the geothermal model of the Lingshui area was established in this study.The deep structure indicates the presence of high-conductivity and low-resistivity layers in the basement of the Baocheng batholith.It can be inferred thereby that asthenospheric upwelling may occur and that there exist two magma vents at depth in the batholith.Therefore,magmatic heat at depth and granites with high radioactive heat generation rate serve as the main heat sources in the Lingshui area. 展开更多
关键词 hainan island Geothermal energy Baocheng batholith GRANITE Radioactive heat flow Thermal conductivity
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Characteristics of Soil Organic Carbon and Total Nitrogen in Rubber Plantations Soil at Different Age Stages in the Western Region of Hainan Island 被引量:17
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作者 吴志祥 谢贵水 +2 位作者 陶忠良 周兆德 王旭 《Agricultural Science & Technology》 CAS 2010年第1期147-153,共7页
[Objective]The aim was to study on the characteristics of soil organic carbon and nitrogen in rubber (Hevea brasiliensis Muell-Arg) plantations at different age stages in the western region of Hainan Island,so as to... [Objective]The aim was to study on the characteristics of soil organic carbon and nitrogen in rubber (Hevea brasiliensis Muell-Arg) plantations at different age stages in the western region of Hainan Island,so as to evaluate the ecological benefits of rubber plantations and provide basic data for studying the effect of tropical land utilization/cover change on the global carbon and nitrogen cycle. [Method]The situs was in Danzhou city,western region of Hainan Island,and the samples were four kinds of rubber plantations soil at different ages and one kind of control check (pepper,Piper nigrum L.) soil. In this research,four quadrats were set up in each sample,and the size of each was 20 cm×20 cm. Four specimens were gathered from four layers of 0-15,15-30,30-45,45-60,and the average of them was the last analysis result of each sample. Soil density was measured by cutting ring method,soil containing and hygroscopic water was detected by oven drying method,soil organic carbon (SOC) was measured by low temperature heated outside potassium dichromate oxidation-colorimetry method,and soil total nitrogen (STN) was detected by semimicro Kjeldahl method. [Result]SOC contents of different layers in rubber plantations soil at different age stages (including the CK pepper soil,the same as below) varied little,and the content of SOC in surface layer (0-15 cm) was higher,while the underlayer (45-60 cm) was lower than the average value; there was significant difference in SOC content among different kinds of soil,and the content was of 6.03-7.78 g/kg,tapping young trees (7 years) CK pepper mature age trees (30 years) prophase of young trees (2 years) tapping trees (16 years); there was no significant difference in SOC storage among different kinds of soil,and the storage was of 61.33-74.29 t/hm2,mature age trees (30 years) tapping young trees (7 years) prophase of young trees (2 years) CK pepper tapping trees (16 years); there was significant difference in STN content among rubber plantations soil at different age stages,the content was of 410.86-664.14 mg/kg2,CK pepper tapping young trees (7 years) prophase of young trees (2 years) mature age trees (30 years) tapping trees (16 years),and STN content of tapping trees (16 years) soil was extremely lowest; there was significant difference in C/N ratio among different kinds of soil,the ratio was of 10.94-14.47,and the ratio of tapping trees (16 years) mature age trees (30 years) tapping young trees (7 years) CK pepper prophase of young trees (2 years). [Conclusion]There wasn't unhealthy effect of rubber trees planted in tropical area on the content and storage of SOC,the content of STN and the ratio of C/N. there was no significant difference between rubber plantations and CK pepper soil,and the effects of rubber plantation on soil carbon-nitrogen was similar to that of other tropical crops (such as pepper). 展开更多
关键词 Different age stages of trees Rubber (Hevea brasiliensis) plantations Soil organic carbon (SOC) Soil total nitrogen (STN) hainan island
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Rattan sector in Hainan Island,China:a case study 被引量:4
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作者 李荣生 尹光天 +1 位作者 杨锦昌 邹文涛 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第2期153-156,共4页
Hainan Island is the biggest supplier of domestic rattan canes in China and is considered the best area to develop rattan plantation in large-scale. This paper discusses the rattan production in Hainan Island on the b... Hainan Island is the biggest supplier of domestic rattan canes in China and is considered the best area to develop rattan plantation in large-scale. This paper discusses the rattan production in Hainan Island on the basis of comprehensively collected information on rattan through interviewing with farmers, middle man, manufacture and official, on-site observation and literatures. The stock of available rattan is more than 25×106kg, but the real production annually is 4×105 kg. The area of rattan plantation established during 2000-2005 was about 10000 hm2, however, they don not produce yet. Four indigenous rattan species (C. Simplicifolius, C. Faberii, C. Tetradactylus, D. margaritae ) and three kinds of exotic canes are mainly utilized in Hainan island. Large quality of canes is treated as timber regulated by government, tax should be paid and a license should be applied from the government if canes are transport out of Hainan Island. The production-to-consumption flow of rattan in Hainan Island was drawn out based on the investigation. Constraints and advantages of the rattan sector in Hainan are identified and recommendations are proposed finally. 展开更多
关键词 Rattan sector hainan island Production-to-consumption
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Species abundance and conservation of coastal wintering waterbirds in Hainan Island,China 被引量:5
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作者 张国钢 梁伟 +6 位作者 刘冬平 钱法文 侯韵秋 苏文拔 kilburn mike holmes jemi 李国诚 《Chinese Birds》 2010年第3期204-210,共7页
Wintering waterbirds surveys were conducted throughout the coastal areas of Hainan,China,from 2003 to 2005,with the aim of further strengthening the conservation and management of wetlands in Hainan Island.A total of ... Wintering waterbirds surveys were conducted throughout the coastal areas of Hainan,China,from 2003 to 2005,with the aim of further strengthening the conservation and management of wetlands in Hainan Island.A total of 68 species were recorded at 20 coastal wetlands.Three recently found wintering sites for the globally endangered Black-faced Spoonbill (Plataleaminor),i.e.Houshui Bay of Lingao,Beili Bay of Dongfang Counties and Sanya River in Sanya City were then extensively monitored during a period of 2003-2009.The largest number of birds were egrets and herons,followed by shorebirds,gulls and terns.On average,the total number of species and individuals at sites with mangrove forests were significantly greater than those of sites without mangrove forests.Some sites,important for conservation,were identified,such as Bopu Bay,Huanglonggang,Houshui Bay,Yangpugang,Beili Bay,Yinggehai,Sanya River,Qinlangang and Dongzhaigang.Thus,human disturbance at these important sites should be avoided. 展开更多
关键词 Black-faced Spoonbill (Plataleaminor) WATERBIRDS hainan island
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The Content of Pb Element and Environmental Quality Assessment in Latosol of Hainan Island 被引量:1
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作者 金联平 毕华 +3 位作者 王鹏 贾双凤 刘志伟 肖智 《Agricultural Science & Technology》 CAS 2011年第10期1509-1512,共4页
[Objective] To research the content of Pb element in latosol of Hainan island and to assess its environmental quality.[Method] Samples were selected for lab analysis.27 samples from different landforms of Hainan Islan... [Objective] To research the content of Pb element in latosol of Hainan island and to assess its environmental quality.[Method] Samples were selected for lab analysis.27 samples from different landforms of Hainan Island were selected(the same place was sampled for three times) to analyze the content of Pb in latosol of Hainan Island,study the spatial distribution feature of this element in latosol from different places and evaluate the content of Pb element in latosol of Hainan Island by geo-accumulation index.[Result] The content of Pb generally stays at high level in latosol of Hainan Island;however,the mean content of Pb in east Hainan is lower than the mean value of west Hainan;vertically,the mean content of Pb shows descending order from hills,mountainous area to plain;the pollution assessment result showed that latosol of Hainan Island was hardly polluted by Pb element and only its content in the latosol from middle,south area stays at high level.[Conclusion] The research provided scientific reference for constructing a national tropical modern agricultural base in Hainan as well as controlling Pb pollution. 展开更多
关键词 hainan island LATOSOL PB DISTRIBUTION Pollution assessment
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Distribution Characteristic and Potential Ecological Risk Assessment of Heavy Metals in Latosol in the Western Area of Hainan Island 被引量:1
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作者 王鹏 赵志忠 +2 位作者 王军广 张忠伟 张子川 《Agricultural Science & Technology》 CAS 2010年第11期145-149,共5页
[Objective] The paper was to carry out ecological geochemical survey and ecological risk assessment on the heavy metals in latosol in western area of Hainan Island.[Method] The contents of six heavy metals including C... [Objective] The paper was to carry out ecological geochemical survey and ecological risk assessment on the heavy metals in latosol in western area of Hainan Island.[Method] The contents of six heavy metals including Cr,Cu,Zn,As,Cd and Pb in latosol in western area of Hainan Island were analyzed.Single-factor index method and Hakanson ecological risk index method were used to evaluate the integrated pollution effect of heavy metals in latosol.[Result] The average contents of Cr,Cu,Zn,As,Cd and Pb in latosol in western area of Hainan Island were 65.57,35.16,93.56,8.50,0.24 and 79.29 mg/kg,respectively.The major pollution factor of heavy metal was Pb.The sequence of influence factors of various heavy metals was PbCu = ZnCrAsCd.The potential ecological risk coefficient of various heavy metals was PbCdCuAsCrZn.The average value of potential ecological risk index(RI)was 45.14,belonging to low ecological risk range.[Conclusion] The heavy metal pollution in latosol in western area of Hainan Island belongs to slight pollution. 展开更多
关键词 hainan island LATOSOL Heavy metal Ecological risk assessment
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Records and Disaster Evaluation of Typhoons in East Hainan Island in Recent 50 Years 被引量:3
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作者 张凯荣 宋长远 陈钰祥 《Meteorological and Environmental Research》 CAS 2010年第7期102-104,108,共4页
Based on typhoon data in Hainan Island from 1957 to 2006,the basic changing characteristics of typhoons' landing on the east of Hainan Island were analyzed.Based on 48 typhoons cases and their disaster conditions,... Based on typhoon data in Hainan Island from 1957 to 2006,the basic changing characteristics of typhoons' landing on the east of Hainan Island were analyzed.Based on 48 typhoons cases and their disaster conditions,objective quantitative grades of typhoon disaster were separated with disaster indicator of typhoon(G) and disaster losses ratio(S).Besides,the disaster assessment was statistically analyzed.The results showed that in the past 50 years,the frequency of typhoons' landing on Hainan Island presented significant annual and monthly changes.The landing locations of typhoons were distributed unevenly.It showed fluctuant changes in disaster indexes of disastrous typhoons,and disaster indexes had increased in the recent 50 years.Typhoon disasters in Hainan Island were catastrophic and a vast majority of those typhoons were of disastrous scales. 展开更多
关键词 hainan island TYPHOON DISASTER Disaster evaluation China
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Three-dimensional P-wave velocity structure of the crust beneath Hainan Island and its adjacent regions,China 被引量:10
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作者 李志雄 雷建设 +3 位作者 赵大鹏 武巴特尔 沈繁銮 丘学林 《地震学报》 CSCD 北大核心 2008年第5期441-448,共8页
Using over 3 500 first P arrival times recorded by nine digital seismic stations from Hainan Digital Seismic Net-work during 1999~2005,a 3-D P-wave velocity model of the crust under Hainan Island and adjacent regions... Using over 3 500 first P arrival times recorded by nine digital seismic stations from Hainan Digital Seismic Net-work during 1999~2005,a 3-D P-wave velocity model of the crust under Hainan Island and adjacent regions has been determined. The results show that the pattern of velocity anomalies in the shallower upper crust is somewhat associated with the surface geological tectonics in the region. A relative low-velocity anomaly appears north of the Wangwu-Wenjiao fault zone and a relative high-velocity anomaly appears south of the Wangwu-Wenjiao fault zone,corresponding to the depressed areas in north Hainan Island,where many volcanoes are frequently active and geothermal values are relatively higher,and the uplifted and stable regions in central and south of the Hainan Is-land. In the middle and lower crust velocities are relatively lower in east Hainan than those in west Hainan,possi-bly suggesting the existence of the upwelling of hot materials from the mantle in east Hainan. The pattern of veloc-ity anomalies also indicates that NW faults,i.e.,the Puqian-Qinglan fault,may be shallower,while the E-W Wangwu-Wenjiao fault may be deeper,which perhaps extends down to Moho depth or deeper. 展开更多
关键词 三维速度 P波 地壳结构 海南岛
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A Survey of the Pteridophyte Herbs of Hainan Island 被引量:21
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作者 杨逢春 梁淑云 《Agricultural Science & Technology》 CAS 2008年第5期136-141,共6页
There are almost 400 species(containing 8 varieties)of pteridophytes on Hainan Island,belonging to 43 families and 114 genera,one third of which are officinal.To understand the distribution of pteridophytes resources ... There are almost 400 species(containing 8 varieties)of pteridophytes on Hainan Island,belonging to 43 families and 114 genera,one third of which are officinal.To understand the distribution of pteridophytes resources of Hainan Island,we conducted this survey mainly by photographing the habitat,plant morphology,sorus and specific traits of some pteridophytes.The results showed that nearly 32 families and 94 species were recorded.These pteridophyte herb resources play important roles in medical treatment of native Li nationality people. 展开更多
关键词 hainan island PTERIDOPHYTE HERBS SURVEY
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Variation of soil fertility and carbon sequestration by planting Hevea brasiliensis in Hainan Island, China 被引量:12
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作者 CHENG Chun-man WANG Ru-song JIANG Ju-sheng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第3期348-352,共5页
The development of rubber industry depends on the sustainable management of rubber plantation. To evaluate the environmental effects of planting Hevea brasiliensis on a subsystem of tropical forest ecosystem, the vari... The development of rubber industry depends on the sustainable management of rubber plantation. To evaluate the environmental effects of planting Hevea brasiliensis on a subsystem of tropical forest ecosystem, the variation of soil fertility and carbon sequestration under rubber plantation within 30-year life period were investigated in Hainan Island. Results showed that (1) with the increase of stand age of rubber plantation, soil fertility decreased all along. From 1954 to 1995, soil organic matter, total N, available K and available P decreased by 48.2%, 54.1%, 56.7% and 64.1%, respectively. (2) If the complete return of litters was considered without additional fertilizer application to the soil of the rubber plantations, the consumption periods for P, N, K, Mg were only 825 years, 329 years, 94 years and 65 years, respectively~ To improve soil fertility is essential for rubber plantation development. (3) The C sequestration of rubber trees per hectare accounts for 272.08 t within 30-year life period and 57.91% of them was fixed in litters. In comparison with C sequestration by rain forest (234.305 t/hm^2) and by secondary rain forest (150.203 t/hm^2), rubber forest has more potentials for C fixation. On the base of above results, the following measures would benefit the maintenance of soil fertility and the development of rubber industry, including applying fertilizer to maintain the balance of soil nutrients, intercropping leguminous plant to improve soil fertility, reducing the collection of litters, optimizing soil properties to improve element P availability such as applying CaCO3. The information gathered from the study can be used as baseline data for the sustainable management of rubber plantation elsewhere. 展开更多
关键词 soil fertility carbon sequestration rubber plantation hainan island
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SOTER-Based Soil Water Erosion Simulation in Hainan Island 被引量:16
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作者 ZHAO YUGUO, ZHANG GANLIN and GONG ZITONGInstitute of Soil Science, the Chinese Academy of Sciences, Nanjing 210008 (China) 《Pedosphere》 SCIE CAS CSCD 2003年第2期139-146,共8页
The actual and potential water erosion rates of soils with different landcovers in Hainan Island, China, were estimated based on the universal soil loss equation (USLE) anda 1:200000 Soils and Terrain Digital Database... The actual and potential water erosion rates of soils with different landcovers in Hainan Island, China, were estimated based on the universal soil loss equation (USLE) anda 1:200000 Soils and Terrain Digital Database (SOTER) database, from which soil water erosionfactors could be extracted. 92.8% of the whole island had a current erosion rate of lower than 500 tkm^(-2) a^(-1). Soil erosion risk was considered to be high because of its abundant rainfall.Without vegetation cover, the potential soil erosion rate would be extremely high and 90.8% of theisland would have a soil erosion rate higher than 2500 t km^(-2) a^(-1). Relative erosionvulnerability of different soil zones, landform types, and lithological regions of the island wascompared by introducing a relative erosion hazard parameter a. Cambosols developed from siltstoneand mudstone in low hill regions were pinpointed as soils with the highest erosion risk in theisland. 展开更多
关键词 hainan island soil erosion risk assessment SOTER USLE
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A wind tunnel simulation of the dynamic processes involved in sand dune formation on the western coast of Hainan Island 被引量:10
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作者 LI Sen LIU Xianwan +2 位作者 LI Huichuan ZHENG Yinghua WEI Xinghu 《Journal of Geographical Sciences》 SCIE CSCD 2007年第4期453-468,共16页
The western coast of Hainan Island exhibits a savanna landscape. Many types of sand dunes, including transverse dune ridges, longitudinal dune ridges, elliptical dunes, coppice dunes, and climbing dunes, are widely di... The western coast of Hainan Island exhibits a savanna landscape. Many types of sand dunes, including transverse dune ridges, longitudinal dune ridges, elliptical dunes, coppice dunes, and climbing dunes, are widely distributed in the coastal zone. In winter, high-frequency and high-energy NE winds (dominant winds) are prevalent, with a resultant drift direction (RDD) of S35.6°W. In spring, low-frequency and low-energy SW secondary winds prevail, with a RDD of N25.1°E. Wind tunnel simulations revealed that the airflow over the dune surface is the main factor controlling the erosion and deposition patterns of dune surfaces and the morphological development of dunes. In the region's bidirectional wind environment, with two seasonally distinct energy levels, the airflow over the surface of elliptical dunes, barchan dunes, and transverse dune ridges will exhibit a transverse pattern, whereas the airflow over longitudinal dunes ridges exhibits a lateral pattern and that over climbing dunes exhibits a climbing-circumfluent pattern. These patterns represent different dynamic processes. The coastal dunes on the western coast of Hainan Island are influenced by factors such as onshore winds, sand sources, coastal slopes, rivers, and forest shelter belts. The source of the sand that supplements these dunes particularly influences the development pattern: when there is more sand, the pattern shows positive equilibrium deposition between dune ridges and dunes; otherwise, it shows negative equilibrium deposition. The presence or absence of forest shelter belts also influences deposition and dune development patterns and transformation of dune forms. Coastal dunes and inland desert dunes experience similar dynamic processes, but the former have more diversified shapes and more complex formation mechanisms. 展开更多
关键词 western coast of hainan island coastal dune surface airflow dynamic processes wind tunnel simulation
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Three-dimensional crustal movement and the activities of earthquakes,volcanoes and faults in Hainan Island,China 被引量:9
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作者 Yaxuan Hu Ming Hao +1 位作者 Lingyun Ji Shangwu Song 《Geodesy and Geodynamics》 2016年第4期284-294,共11页
Hainan Island is a seismic active region, where Qiongshan M7.5 earthquake occurred in 1605 and several seismic belts appeared in recent years, especially the NS trending seismic belt (NSB) located in the northeast p... Hainan Island is a seismic active region, where Qiongshan M7.5 earthquake occurred in 1605 and several seismic belts appeared in recent years, especially the NS trending seismic belt (NSB) located in the northeast part of the island. Here is also a magmatic active region. The lava from about 100 volcanoes covered more than 4000 km^2. The latest eruptions occurred on Ma'anling-Lei Huling volcanoes within 10,000 years. The neotectonic movement has been determined by geological method in the island and its adjacent areas. In the paper, the present-day 3D crustal movement is obtained by using Global Positioning System (GPS) data observed from 2009 to 2014 and leveling observations measured in 1970s and 1990s respectively. The results show the horizontal movement is mainly along SEE direction relative to the Eurasian Plate. The velocities are between 4.01 and 6.70 mm/a. The tension rate near the NSB is less than I mm/a. The vertical movement shows the island uplifts as a whole with respect to the reference benchmark Xiuyinggang. The average uplifting rate is 2.4 mm/a. The rates are 2-3 mm/a in the northwest and 3-5mm/a in the northwest. It shows the deformation pattern of the southwest island is upward relative to the northeast, which is different from the result inferred from the coastal change and GPS. Haikou and its adjacent region present a subsidence in a long time. The southern part of the middle segment of the Wangwu-Wenjiao fault uplifts relative to the northern. Meanwhile, the western part uplifts relative to the eastern NSB. The vertical crustal motion and the two normal faults nearly correspond to the terrain. The NSB is located along the Puqiangang-Dazhibo fault, which is assessed as a segmented fault with a dip of 80°-90° and party exposed. The 3D deformations and other studies reveal the present activities of earthquakes, volcanoes and the faults. The small earthquakes will still occur in the NS belt and the volcanoes are not active now. 展开更多
关键词 hainan island Horizontal movement Vertical movement EARTHQUAKE VOLCANO FAULT Seismic belt
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Mean water level setup/setdown in the inlet-lagoon system induced by tidal action—a case study of Xincun Inlet,Hainan Island in China 被引量:7
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作者 GONG Wenping SHEN Jian WANG Daoru 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2008年第5期63-80,共18页
With the tides propagating from the open sea to the lagoon, the mean water level (MWL) in the inlet and lagoon becomes different from that at the open sea, and a setup/setdown is generated. The change of MWL (setup... With the tides propagating from the open sea to the lagoon, the mean water level (MWL) in the inlet and lagoon becomes different from that at the open sea, and a setup/setdown is generated. The change of MWL (setup/setdown) in the system imposes a great impact on regulating the development of tidal marshes, on determining the long-term water level for harbor maintenance, on the planning for the water front development with the flood control for the possible inundation, and on the interpretation of the historical sea level change when using tidal marsh peat deposits in the lagoon as the indicator for open sea' s sea level. In this case study on the mechanisms which control the setup/setdown in Xincun Inlet, Hainan in China, the 2-D barotropic mode of Eulerian - Lagrangian CIRCulation (ELCIRC) model was utilized. After model calibration and verification, a series of numerical experiments were conducted to examine the effects of bottom friction and advection terms, wetting and drying of intertidal areas, bathymetry and boundary conditions on the setup/setdown in the system. The modeling results show that setup occurs over the inlet and lagoon areas with an order of one tenth of the tide range at the entrance. The larger the bottom friction is, a larger setup is generated. Without the advection term, the setup is reduced clue to a decrease of water level gradient to compensate for the disappearance of the advection term. Even without overtides, a setup can still be developed in the system. Sea level rise and dredging in the inlet and tidal channel can cause a decrease of setup in the system, whereas shoaling of the system can increase the setup. The uniqueness of the Xincun Inlet with respect to MWL change is that there is no evident setdown in the inlet, which can be attributed to the complex geometry and bathymetry associated with the inlet system. 展开更多
关键词 tidal inlet water level setup/setdown ELCIRC hainan island
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Characteristics and Preliminary Causes of Tropical Cyclone Extreme Rainfall Events over Hainan Island 被引量:8
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作者 Xianling JIANG Fumin REN +3 位作者 Yunjie LI Wenyu QIU Zhuguo MA Qinbo CAI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第5期580-591,共12页
The characteristics of tropical cyclone(TC) extreme rainfall events over Hainan Island from 1969 to 2014 are analyzed from the viewpoint of the TC maximum daily rainfall(TMDR) using daily station precipitation dat... The characteristics of tropical cyclone(TC) extreme rainfall events over Hainan Island from 1969 to 2014 are analyzed from the viewpoint of the TC maximum daily rainfall(TMDR) using daily station precipitation data from the Meteorological Information Center of the China Meteorological Administration, TC best-track data from the Shanghai Typhoon Institute,and NCEP/NCAR reanalysis data. The frequencies of the TMDR reaching 50, 100 and 250 mm show a decreasing trend[-0.7(10 yr)^(-1)], a weak decreasing trend [-0.2(10 yr)^(-1)] and a weak increasing trend [0.1(10 yr)^(-1)], respectively. For seasonal variations, the TMDR of all intensity grades mainly occurs from July to October, with the frequencies of TMDR 50 mm and 100 mm peaking in September and the frequency of TMDR 250 mm [TC extreme rainstorm(TCER) events]peaking in August and September. The western region(Changjiang) of the Island is always the rainfall center, independent of the intensity or frequencies of different intensity grades. The causes of TCERs are also explored and the results show that topography plays a key role in the characteristics of the rainfall events. TCERs are easily induced on the windward slopes of Wuzhi Mountain, with the coordination of TC tracks and TC wind structure. A slower speed of movement, a stronger TC intensity and a farther westward track are all conducive to extreme rainfall events. A weaker northwestern Pacific subtropical high is likely to make the 500-h Pa steering flow weaker and results in slower TC movement, whereas a stronger South China Sea summer monsoon can carry a higher moisture flux. These two environmental factors are both favorable for TCERs. 展开更多
关键词 hainan island tropical cyclones extreme rainfall events CHARACTERISTICS CAUSES
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Exploring suitability for tropical crop cultivation in Hainan Island by SOTAL methodology 被引量:9
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作者 Zhang Xue-lei S.Mantel +1 位作者 Zhang Gan-lin V.W.P.van Engelen 《Journal of Geographical Sciences》 SCIE CSCD 2001年第4期40-46,共7页
A SOTER-based automatic procedure for qualitative land evaluation is developed. This procedure was created in the automated land evaluation system (ALES). The objective was to design a procedure that allows for a quic... A SOTER-based automatic procedure for qualitative land evaluation is developed. This procedure was created in the automated land evaluation system (ALES). The objective was to design a procedure that allows for a quick separation of potentially suitable from non-suitable SOTER units for the intended land use, indicating constraints to different kinds of land use. Different kinds of land are unequal1y suited to various uses, land eva1uation is the assessment of the suitability of a tract of land for a specified kind of land use. In practice this implicates the comparison (matching) between the requirements of a specified land use and the properties of the land. Land evaluation concepts and definitions are treated in the paper. The ALES is a computer program that allows land evaluators to build their own knowledge-based system with which they can compute the physical and economical suitability of map units in accordance with FAO framework for land evaluation. The ALES program works with so-called decision trees, being hierarchical multiway keys in which the leaves are results (e.g., severity levels of land qualities), and the interior nodes of the tree are decision criteria (e.g., land characteristic values). These trees are traversed by the program to compute an evaluation using actual land data for each map unit. SOTAL is a SOTER-based qualitative model developed in ALES for physical land evaluation in which presently three land utilization types (LUTs) are distinguished, i.e., cultivated banana, coffee and rubber under different input and technological conditions. These LUTs are characterized by 11 landuse requirements and evaluated by matching the land use requirements with the corresponding land qualities. The paper elaborates on the criteria used in SOTAL for land quality assessment and how a final suitability rating is achieved on the basis of the rated land qualities. Results are visualized through G1S-generated maps as products in response to the specific information and data needs of decision and policy makers. 展开更多
关键词 EVALUATION tropical crops HaiSOTER hainan island
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Helium,Argon and Carbon Isotopic Compositions of Spring Gases in the Hainan Island,China 被引量:7
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作者 XU Sheng ZHENG Guodong XU Yongchang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第6期1515-1523,共9页
Chemical and isotopic compositions have been measured for N2-He-rich bubbling gases discharging from hot springs in the Hainan Island, Southern China. Observed 3He/4He ratios (0.1-1.3 RA) indicate the occurrence of ... Chemical and isotopic compositions have been measured for N2-He-rich bubbling gases discharging from hot springs in the Hainan Island, Southern China. Observed 3He/4He ratios (0.1-1.3 RA) indicate the occurrence of a mantle component throughout the island, which has been highly diluted by a crustal radiogenic 4He component. The occurrence of mantle-derived helium is high in the northern island (12%-16% of total He) and gradually decreases towards southern coast (1%-3% of total He). Such a distribution pattern is most likely controlled by the Pleocene-Quaternary volcanic activities in the northern island and groundwater circulation along the deep major faults. The 4~Ar/36Ar and N2/Ar ratios suggest that N2 and Ar of the hot spring gases are mostly meteoric. Although 13C values of CO2 (-20%0 to -27%0) with low concentrations are consistent with the biogenic origin, the combination of SHe/4He and 51SCco2 suggests a two end-member mixing of mantle and crustal components with CO2/3He ratios of 2x 109 and 8 1011, respectively. However, the low CO2/3He ratios (1- 22106) can not be ascribed in terms of the simple mixing but has to be explained by the addition of radiogenic 4He and loss of CO2 by calcite precipitation in the hydrothermal system, which is most likely controlled by the degree of gas-water-rock interaction. 展开更多
关键词 He-Ar-C isotopes mantle-derived He hot spring gas hainan island
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Land Use-Related Changes in Soils of Hainan Island During the Past Half Century 被引量:9
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作者 GONG ZITONG, ZHANG GANLIN, ZHAO WENJUN, ZHAO YUGUO and CHEN ZHICHENGInstitute of Soil Science, the Chinese Academy of Sciences, Nanjing 210008 (China) 《Pedosphere》 SCIE CAS CSCD 2003年第1期11-22,共12页
During the past half century, the land utilization of Hainan Island has undergone a rapid development,but in the meanwhile, soil degradation occurs. Analysis on some basic data of the soil series collected frommore th... During the past half century, the land utilization of Hainan Island has undergone a rapid development,but in the meanwhile, soil degradation occurs. Analysis on some basic data of the soil series collected frommore than 100 soil profiles at the end of the 1990s and beginning of this century, in combination with dataavailable, showed that soils there suffered significant decline in organic matter, experienced P and K deficiencywith soil K going on losing and undergone acidification with continuing trend. The current situation calls forstrategies to build up Hainan into an important province of sound ecology by restoring forests, to improvefood quality by implementing K supplement projects, to combat soil acidification by ameliorating the soils andgrowing leguminous crops and to ensure health of the people by developing dairy production and increasingthe daily Ca uptake by the people. 展开更多
关键词 hainan island land use soil changes
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REPORT ON PONTONIINE SHRIMPS (CRUSTACEA: DECAPODA) COLLECTED BY JOINT CHINESE-GERMAN MARINE BIOLOGY EXPEDITIONS TO HAINAN ISLAND,SOUTH CHINA SEA I. ANCHISTUS, CONCHODYTES, CORALLIOCARIS 被引量:4
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作者 李新正 刘瑞玉 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第4期371-377,共7页
The present paper reports 7 species of pontoniine shrimps collected from Hainan Island, South China Sea, by the Joint Chinese German Marine Biology Expeditions, in which, Conchodytes nipponensis (De Haan, 1844) and Co... The present paper reports 7 species of pontoniine shrimps collected from Hainan Island, South China Sea, by the Joint Chinese German Marine Biology Expeditions, in which, Conchodytes nipponensis (De Haan, 1844) and Coralliocaris brevirostris Borradaile, 1898 are new records from Chinese waters. 展开更多
关键词 Pontoniinae Anshistus Conchodytes Coralliocaris hainan island
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