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Spatial Characteristic Analysis of the Comparative Advantage of Watermelon and Melon Production in Hainan Province 被引量:1
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作者 柳唐镜 张棵 +3 位作者 别之龙 许勇 李劲松 孔秋生 《Agricultural Science & Technology》 CAS 2013年第4期582-588,605,共8页
[Objective] This study investigated the spatial characteristics of counties (cities) with comparative advantages in watermelon and melon production to provide reference bases in formulating strategies for the develo... [Objective] This study investigated the spatial characteristics of counties (cities) with comparative advantages in watermelon and melon production to provide reference bases in formulating strategies for the development of watermelon and melon industries in Hainan Province. [Method] By using the sowing area, total yield, and yield per unit area of watermelon and melon in Hainan Province as research u- nits, the yield comparative advantage (YCA), efficiency comparative advantage (E- CA), scale comparative advantage (SCA), concentration ratio comparative advantage (CRCA), comprehensive comparative advantage (CCA), ratio of yield per unit area (RYPA), sowing area ratio (SAR), and distribution characteristics of watermelon and melon were systematically analyzed. By referring to the agricultural statistic data of 18 counties (cities) in Hainan Province, indexes for each research unit (i.e., the YCA index, ECA index, SCA index, CRCA index, CCA index, RYPA index, and SAR index) were established and calculated to determine the comparative advantage of watermelon and melon production in Hainan Province. A spatial expression of the research result on a map was conducted by using GIS software. [Result] Seven counties (cities) exhibited comparative advantages in watermelon production, namely, Lingshui, Wanning, Wenchang, Dongfang, Sanya, Ledong, and Changjiang. The Eastern and Southern Hainan Provinces had CCAs, and the Western and Northern Hainan Provinces could be reserved for future development. For melon production, four counties (cities) exhibited comparative advantages, namely, Ledong, Lingshui, Sanya, and Dongfang. The Southern Hainan Province had CCA, whereas the West- ern Hainan Province could be reserved for later development. [Conclusion] The result has showed that establishing watermelon and melon as dominant agricultural prod- ucts is necessary for the future development of the industry and for the formulation of a layout of regions with advantages, where key support and construction should be provided preferentially with the aim to raise the yield, quality, and market com- petitiveness of products. 展开更多
关键词 WATERMELON MELON Comparative advantage Spatial analysis hainan province
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Wild Ornamental Plant Resources and Their Application to City Gardening in Hainan Province 被引量:1
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作者 侯则红 余雪标 陈展川 《Journal of Landscape Research》 2009年第6期59-63,共5页
This paper deals with the wild ornamental plant resources which are suitable for the application to gardening in Hainan Province and with the significance and the influencing factors in the application and extension o... This paper deals with the wild ornamental plant resources which are suitable for the application to gardening in Hainan Province and with the significance and the influencing factors in the application and extension of these resources to gardening. The strategies for the application of the wild ornamental plant resources have been established as the result of this research. 展开更多
关键词 WILD ORNAMENTAL plants hainan province GARDENING CULTIVATION APPLICATION
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Geomorphology of the Boao coastal system and potential effects of human activities-Hainan Island,South China 被引量:2
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作者 ZHUDakui YINYong PeterMARTINI 《Journal of Geographical Sciences》 SCIE CSCD 2005年第2期187-198,共12页
The Boao coastal system along the eastern coast of Hainan Island is a dynamic delta-tidal inlet-barrier formed during the late Holocene. The delta developed inside a shallow lagoon barred by a sandy barrier with a nar... The Boao coastal system along the eastern coast of Hainan Island is a dynamic delta-tidal inlet-barrier formed during the late Holocene. The delta developed inside a shallow lagoon barred by a sandy barrier with a narrow, shallow tidal inlet opening. Two major distributary channels separated by small islands characterize the delta. The lagoon is silting up receiving and trapping sediments from both the river and, in minor measure during storms, through the tidal inlet opening and barrier washovers. The barrier at the tidal inlet is highly dynamic and changes its form, accreting (migrating spit) against the inlet during fair-weather conditions and being eroded during storms and river floods. The delta has almost completely filled the lagoon and major concerns exist on the effect that ongoing large development plans may have on the environment. These concerns include the effect on floods and rate of siltation once banks of the islands have been stabilized and floodwater and sediment load are impeded from spreading over the lowlands, and the effect of increasing pollutant loads from the new facilities on the ecosystems of the increasingly restricting lagoon water and on the seashores. 展开更多
关键词 ESTUARY coastal barrier coastal erosion tidal inlet flooding prevention LAGOON boao hainan Island Wanquan River delta Ground-Penetrating Radar
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Research on Coconut Germplasm Resource in Hainan Province 被引量:1
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作者 毛彧 傅国华 《Agricultural Science & Technology》 CAS 2010年第11期137-140,149,共5页
The researches on coconut germplasm resource of Hainan Province and its importance were reviewed in this study.The classification and characters of coconut germplasm resource in Hainan Province,as well as its developm... The researches on coconut germplasm resource of Hainan Province and its importance were reviewed in this study.The classification and characters of coconut germplasm resource in Hainan Province,as well as its development and utilization of were summarized.In addition,some of the problems in researches on coconut germplasm resource and the potential research directions were discussed. 展开更多
关键词 hainan province COCONUT Germplasm resource
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The Shilu Iron Ore Deposit in Hainan Province,South China:A Structurally and Hydrothermally Reworked and Re-Enriched Lake-Superior-Type BIF Iron Deposit
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作者 Bakun-Czubarow Nonna Kusiak Monika Agnieszka 《矿物学报》 CAS CSCD 北大核心 2009年第S1期573-574,共2页
The Shilu iron ore deposit,located in the western Hainan Province,South China,is one of the most important iron-ore mining districts in China not only for its huge reserves of hematite-rich ores,but also for its poten... The Shilu iron ore deposit,located in the western Hainan Province,South China,is one of the most important iron-ore mining districts in China not only for its huge reserves of hematite-rich ores,but also for its potentially economic significance of associated metals of copper,cobalt,nickel,silver,lead and zinc,and of non-metals of dolomite,quartzite,barite,gypsum and sulfur. 展开更多
关键词 BIF LAKE The Shilu Iron Ore Deposit in hainan province South China
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Holiday Tour Package in Hainan Province
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《China's Foreign Trade》 1996年第7期46-47,共2页
In order to coordinate the themeactivities of the ’96 China HolidayTour,Hainan Province has releaseda batch of new tourism packages.They include:
关键词 BAY LI Holiday Tour Package in hainan province
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Zhengquan Hi-tech Co. Ltd in Hainan Province
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作者 Xiao Huang 《China's Foreign Trade》 1996年第5期44-44,共1页
At the first international farm produceseminar and foreign-funded projecttalks co-sponsored by the EconomicDaily and the Beiyang group at the beginningof 1996,the Zhengquan Hi-tech Co.Ltdbased in Hainan brought to the... At the first international farm produceseminar and foreign-funded projecttalks co-sponsored by the EconomicDaily and the Beiyang group at the beginningof 1996,the Zhengquan Hi-tech Co.Ltdbased in Hainan brought to the attention ofdomestic and foreign clients and experts itsapplication of plant endotropic bacteriumtheory to agriculture and industry. The company is a multi-industrialshareholding enterprise engaged in developinghi-tech products in the fields of agriculture,animal husbandry,food and medicines. Two scientists from the 展开更多
关键词 Zhengquan Hi-tech Co Ltd in hainan province
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Workshop on rice production of China was held at Hainan Province
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作者 Lin Ronghui,CNRRI 《Chinese Rice Research Newsletter》 1996年第2期12-12,共1页
A workshop on rice production of China was held at Hainan Province on Jan. 16-17, 1996. The purpose of the workshop was to discuss the strategy for acquiring the bumper harvest of rice in 1996 and the goal of rice pro... A workshop on rice production of China was held at Hainan Province on Jan. 16-17, 1996. The purpose of the workshop was to discuss the strategy for acquiring the bumper harvest of rice in 1996 and the goal of rice production-during the "Ninth Five-year Plant". According to the project set up by the Chinese Ministry of Agriculture, the rice yield in China has to reach 195 billion kg in 2000 AC. This means that at least the rice yield has to be increased by 2.5 billion kg every year progressively during 1996—2000. The participants put forward several rationalization proposals such as recovering the cultivated area of early rice, developing the cultivation of ratooning rice and 展开更多
关键词 Workshop on rice production of China was held at hainan province
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Effects and mechanism of igneous rock on selenium in the tropical soil-rice system in Hainan Province, South China 被引量:7
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作者 Xiu-jin Liu Ke Yang +5 位作者 Fei Guo Shi-qi Tang Ying-han Liu Li Zhang Hang-xin Cheng Fei Liu 《China Geology》 2022年第1期1-11,共11页
To illuminate the migration and transformation of selenium(Se)in the igneous rock-soil-rice system,285 pairs of rhizosphere soil and rice samples were collected from the granitoid and basalt areas in Hainan Province,S... To illuminate the migration and transformation of selenium(Se)in the igneous rock-soil-rice system,285 pairs of rhizosphere soil and rice samples were collected from the granitoid and basalt areas in Hainan Province,South China.The contents of Se in soils derived from granitoid and basalt are,respectively,0.19±0.12 mg/kg and 0.34±0.39 mg/kg,which are much higher than Se contents in granitoid and basalt.Selenium shows remarkable enrichment from granitoid and basalt to soils.The mobile fraction of Se in soils derived from granitoid is 0.0100±0.0034 mg/kg,which is significantly higher than that of basalt(0.0058±0.0039 mg/kg).Although soil derived from basalt shows higher Se contents,Se contents in rice samples,mobile fractions of Se in soils,and biological concentration factor(BCF)is similar or even lower than that from granitoid.Basalt consist of calcic plagioclase and pyroxene,and are much richer in Fe,Al,and Ca than granitoid.Correspondingly,the basalt-derived soils have higher goethite,hematite,kaolinite,cation exchange capacity(CEC)content,and higher p H than the granitoid-derived soils,which result in higher adsorption capacity for Se and relatively lower Se bioavailability.Soils derived from granitoid and basalt in tropical regions are beneficial to produce Se-rich rice. 展开更多
关键词 SELENIUM GRANITOID BASALT Soil properties Tropical soil Se-rich rice Agricutural geological survey engineering hainan province China
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Quantitative Appraisement on Ecological Carrying Capacity in Coastal Rapid Developing Region of Hainan Province 被引量:3
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作者 Zhang Fugang Liu Yansui 《Chinese Journal of Population,Resources and Environment》 北大核心 2008年第2期87-92,共6页
The ecological carrying capacity,an important indica- tor to evaluate the sustainable development of the ecosystem, means the potential ability of the natural ecosystem to carry so- cioeconomic development while the e... The ecological carrying capacity,an important indica- tor to evaluate the sustainable development of the ecosystem, means the potential ability of the natural ecosystem to carry so- cioeconomic development while the ecosystem is healthy.It is limited by the carrying capacity of natural resources and environ- ment and the elasticity of the ecosystem.It will be greatly signifi- cant to study the ecological carrying capacity of Hainan Province, the first ecological province admitted by the State Environmental Protection Administration in China.Not only is the natural eco- system reflected,but also the effects of human activities are em- phasized by integrating the ecosystem health analysis into the ecological carrying capacity research.The research results,using the Factor Analysis tools of software SPSS,indicate that the eco- logical carrying capacity of Hainan Province fluctuated obviously from 1996 to 2005.The level of the ecological carrying capacity of Hainan Province was relatively high in 1996,and reached into trough from 1997 to 1999.It has steadily ascended to be above the middle level since the 21st century.The results also show that policy factors,especially the implementation of the 'Ecological Province' strategy,were important driving forces to influence the ecological carrying capacity.With the population rapidly increas- ing,the land and water resources per capita have decreased quickly.The amount of the ecological carrying capacity was pro- moted remarkably by socioeconomic development especially economic growth and technology applications.All of these will provide useful suggestions to establish and enact regional devel- opment policies,especially for protecting and reconstructing the ecology and environment of Hainan Province. 展开更多
关键词 ecological carrying capacity evaluation driving forces hainan province
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Developmental Strategies of Betel Nut Industry in Hainan Province 被引量:1
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作者 CHEN Jun, HAN Xuan, LIU Li-yun, FENG Mei-li, LI Zhuan, QIN Hai-tang Coconut Research Institute of China Academy of Tropical Agricultural Sciences, Wenchang 571339, China 《Asian Agricultural Research》 2010年第12期1-4,共4页
The developmental status of the betel nut industry is introduced, including cultivation situation, processing and development situation, and consumer market situation. The result shows that the cultivation of betel nu... The developmental status of the betel nut industry is introduced, including cultivation situation, processing and development situation, and consumer market situation. The result shows that the cultivation of betel nut in Hainan Province develops rapidly and the primary processing of betel nut has formed certain scale, but the deep processing of betel nut is backward. Except for the mino amount of the betel nuts consumed by Hainan Island, a large majority of the betel nuts are processed into dry fruit to sell to Hunan Province to reprocess. The problems exist in the development of betel nut industry in Hainan Province are analyzed, covering blind cultivation, extensive management, backward processing, lagged new product development and the single and concentrated consumer market. The strategic choice of developing the betel nut industry of Hainan Province is analyzed as well. Hainan Province should carry out the green, sustainable, diversified, cooperative and export-oriented industrial developmental strategy. 展开更多
关键词 BETEL NUT hainan province INDUSTRY DEVELOPMENTAL s
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Energy consumption,indoor environmental quality,and benchmark for office buildings in Hainan Province of China 被引量:1
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作者 孔祥飞 吕石磊 +1 位作者 辛亚娟 吴薇 《Journal of Central South University》 SCIE EI CAS 2012年第3期783-790,共8页
With rapid economy growth,building energy consumption in China has been gradually increased.The energy consumption and indoor environmental quality of 51 office buildings in Hainan Province,a hot and humid area,were s... With rapid economy growth,building energy consumption in China has been gradually increased.The energy consumption and indoor environmental quality of 51 office buildings in Hainan Province,a hot and humid area,were studied through collection of verified data in site visits and field tests.The result revealed that,electricity accounted for 99.79% of the total energy consumption,natural gas 0.17%,and diesel 0.04%.The air conditioning dominated the energy use with a share of 43.18%,equipment in the particular areas 26.90%,equipment in the office rooms 11.95%,lighting system 8.67%,general service system 7.57%,and miscellaneous items 1.73%.Statistical method including six indicators obtained the energy consumption benchmark with upper limit of 98.31 kW-h/m2 and lower limit of 55.26 kW-h/m2.According to ASHRAE standard(comfortable standard) and GB/T 18883-2002(acceptable standard),the indoor environmental quality of 51 sampled office buildings was classified into three ranks:good,normal and bad.With benchmark of building energy consumption combined with indoor environmental quality,it was found that only 3.92% of sampled buildings can be identified as the best performance buildings with low energy consumption and advanced indoor environmental quality,and the buildings classified into normal level accounted for the maximum ratio. 展开更多
关键词 building energy consumption BENCHMARK indoor environmental quality energy use index hainan province
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Molecular Detection and Identification of Candidatus Ehrlichia Hainanensis,A Novel Ehrlichia Species in Rodents from Hainan Province,China 被引量:1
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作者 ZHAO Hong Qing LIU Pei Pei +3 位作者 XUE Feng LU Miao QIN Xin Cheng LI Kun 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2021年第12期1020-1023,共4页
Ehrlichia(Anaplasmataceae family)are obligatory intracellular bacteria that infect humans and animals.They are hosted by mammals such as canines,bovines and wild rodents,and are vectored by ticks.In this study,we coll... Ehrlichia(Anaplasmataceae family)are obligatory intracellular bacteria that infect humans and animals.They are hosted by mammals such as canines,bovines and wild rodents,and are vectored by ticks.In this study,we collected 121 rodent samples comprising 67 Niviventer fulvescens,27 Rattus tanezumi,24 Chiromyscus sp.,2 Rattus nitidus and 1 Leopoldamys edwardsi from Hainan province,which includes the second largest island in China.The presence and genetic diversity of Ehrlichia species was evaluated and characterized by amplification and sequencing of 16S rRNA,groEL and gltA genes.An Ehrlichia species was detected in 5 of the 67 Niviventer fulvescens samples(7.46%).The 16S rRNA,groEL and gltA genes showed the highest identity to known Ehrlichia sequences(99.20%,89.87%and 83.86%,respectively).In the phylogenetic trees they formed a cluster distinct from all other species.We propose that this species is a putative novel Ehrlichia species,which we suggest be named Candidatus Ehrlichia hainanensis.Its pathogenicity to humans remains to be further researched,and molecular surveillance in local populations is needed. 展开更多
关键词 Candidatus Ehrlichia hainanensis hainan province Niviventer fulvescens
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Legislation,challenges and solutions for the"Dream of the Island Owner"--Review of the application and approval measures on the development and utilization of uninhabited islands in Hainan Province 被引量:1
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作者 DENG Yuncheng 《Marine Science Bulletin》 CAS 2020年第1期73-89,共17页
China's legislation relating to islands categorizes the latter into inhabited and uninhabited ones.Between the two different types,only uninhabited islands can be acquired by those who aspire to be private island ... China's legislation relating to islands categorizes the latter into inhabited and uninhabited ones.Between the two different types,only uninhabited islands can be acquired by those who aspire to be private island owners.In an effort to promote the development and utilization of uninhabited islands in China,a succession of laws and regulations have been formulated,including the Law of the People's Republic of China on the Protection of Offshore Islands,and the Application and Approval Measures on the Development and Utilization of Uninhabited Islands,among others.As the only tropical province in China,Hainan province boasts a large number of uninhabited islands,many of which are desired by prospective island owners.In order to promote the development of uninhabited islands,the Application and Approval Measures on the Development and Utilization of Uninhabited Islands in Hainan Province had been promulgated.Based on a detailed introduction on the main contents of the Measures,it is found that the Measures has set an innovative example for its kind in terms of the real estate publicity system,the construction permit and acceptance systems,solutions to using the islands before the issue of Island Protection Law,and verification systems.Nevertheless,the actual implementation of the Measures still brings a host of challenges with it.These relate to aspects of the Measures such as supply regulation premised on regulatory equilibrium,spatial planning with"Multiple-plan Coordination",and coordination between regulations on sea areas and islands.This paper proposes to maximize efforts to refine and coordinate general planning,to innovate systems and procedures regarding the use of islands and to promote the development and utilization of uninhabited islands through protective development in line with international standards. 展开更多
关键词 island owners uninhabited islands legal system hainan province
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DEA Analysis of Agricultural Production Efficiency in Hainan Province 被引量:2
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作者 TANG Yao-yan,CAI Dui School of Economics and Management,Hainan University,Haikou 570228,China 《Asian Agricultural Research》 2011年第4期34-36,共3页
On the basis of summarizing some literatures regarding research of agricultural production efficiency by using DEA at home,we conduct empirical analysis on agricultural production efficiency in 18 cities or counties o... On the basis of summarizing some literatures regarding research of agricultural production efficiency by using DEA at home,we conduct empirical analysis on agricultural production efficiency in 18 cities or counties of Hainan Province in the year 2002,2005 and 2008 by using DEA model.The results show that in 2005 Hainan Province suffered from unusual drought and windstorm,which made the effective value of agricultural production in all cities or counties relatively low;the regions with DEA effectiveness of agricultural production in the year 2002,2005 and 2008 were Qionghai City,Tunchang County,Lingao County,Danzhou City,Qiongzhong County and Baisha County.Haikou City,Wuzhishan City and Baoting County in the year 2002,Lingshui County in the year 2005,and Sanya City and Dongfang County in the year 2008 were also regions with DEA effectiveness,indicating that the input-output of these regions in the corresponding years is in optimal state.Finally,we conduct projection analysis on six cities and counties with non-DEA effectiveness in the year 2008 in Hainan Province,and based on this,find out the approach of improving agricultural production efficiency in these regions. 展开更多
关键词 DEA AGRICULTURAL PRODUCTION EFFICIENCY hainan Prov
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THE CHANGING TENDENCY OF LAND RESOURCES AND THE COUNTERMEASURES IN HAINAN PROVINCE IN 2000
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作者 温长恩 肖志斌 《Chinese Geographical Science》 SCIE CSCD 1993年第2期44-52,共9页
Hainan Provine, with an land area of 34,170 km2, is the largest economic district for external development in China. With the further deepening of reform and openning up, some new problems of land resource exploitatio... Hainan Provine, with an land area of 34,170 km2, is the largest economic district for external development in China. With the further deepening of reform and openning up, some new problems of land resource exploitation and use have arisen. The changing tendency of land use is estimated as follows: Land use in economic exploitation, city development and traffic will be increased rapidly; hydraulic construction will occupy a part of land; the use of wasteland is increasing; and the total farmland and per capital farmland will decrease continously. In 2000, the occupied land should be controlled in 5 million mu (1 mu=1/ 15 ha), in which farmland is 160,000 mu. The farmland should be maintained in 6.5 million mu. Some measures to implement the strategy and object of land use are put forward: enhancing land management and administration; excuting land policy and making land management mechanism active; enhancing the efficiency of land use; and control the growth of population strictly. 展开更多
关键词 LAND RESOURCES LAND use resource estimation hainan province
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LAND USE STRATEGIES IN SPECIAL ECONOMIC ZONES OF CHINA:THE CASE STUDY OF HAINAN PROVINCE
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作者 Cai Yunlong(Department of Geography, Peking University, Beijing 100871People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1995年第2期13-20,共8页
Special economic zones are important bridges between Chinaand intemational market. Their economic structure is being transformed andnew land use strategies should be taken correspondingly. HainanProvince, as the big... Special economic zones are important bridges between Chinaand intemational market. Their economic structure is being transformed andnew land use strategies should be taken correspondingly. HainanProvince, as the biggest special economic zone, has great superiorities andpotentialities for the development of land use. In order to realize the goal,the present land use decision should be mainly guided by market, moreattention should be paid to tropical agriculture and aquatic productindustry, the principle of sustainable development should be strengthened,and the area of farmland for grain production should be stabilized. 展开更多
关键词 land use situation and strategy special economic zone China hainan province
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Study on Banana Cooperatives in Hainan Province
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作者 Huide HUANG Wanzhen ZHANG +1 位作者 Enping LIU Xizhu ZHANG 《Asian Agricultural Research》 2013年第7期70-72,共3页
This paper gives an overview of the distribution,member scale,production and operation of banana cooperatives in Hainan Province,and points out the market risk and natural risk faced by the production of banana cooper... This paper gives an overview of the distribution,member scale,production and operation of banana cooperatives in Hainan Province,and points out the market risk and natural risk faced by the production of banana cooperatives in Hainan Province. In order to promote the banana cooperatives to form new agricultural management system integrating organization and intensification,this paper puts forth the production and operation recommendations,such as joint production of banana cooperatives,timely planting of banana,brand management,and improvement of production and operation technical level. 展开更多
关键词 hainan province BANANA Cooperatives CURRENT situat
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Petrology and geochemistry of the Shilu Fe-polymetallic ore deposit in Hainan Province of South China: Implications for the origin of Neoproterozoic BIFs
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作者 Deru Xu Zhilin Wang +3 位作者 Jianxin Cai Chuanjun Wu Wangwei Fu Nonna Bakun-Czubarow 《矿床地质》 CAS CSCD 北大核心 2012年第S1期139-140,共2页
The Shilu Fe-polymetallic ore deposit,a famous hematite-rich Fe-ore deposit,is situated at the western Hainan Province of south China.The deposit characterizes the upper Fe ores and the lower Co-Cu ores,which are main... The Shilu Fe-polymetallic ore deposit,a famous hematite-rich Fe-ore deposit,is situated at the western Hainan Province of south China.The deposit characterizes the upper Fe ores and the lower Co-Cu ores,which are mainly hosted within a low-grade to medium-grade,dominantly submarine metamorphosed siliciclastic and carbonate sedimentary succession of the Neoproterozoic Shilu Group.Three facies types of metamorphosed BIFs,i.e.the oxide facies,the silicate-oxide facies and the sulfide-carbonate facies BIFs,are identified within the sixth sequence of the Shilu Group.The oxide facies BIF(i.e.the Fe-rich itabirites or ores)consists of alternating hematite-rich microbands with quartz-rich microbands;the silicate-oxide facies BIF(i.e.the Fe-poor itabirites or ores)comprises alternating millimeter-to a few tens meter-scale,magnetite-hematite-rich bands with calcsilicate-rich(garnet+actinolite+diopside+epidote+quartz)meso-to microbands;and the sulfide-carbonate facies BIF(i.e.the Co-Cu ores)contains alternating macro-to mesobands of Co-bearing pyrite and pyrrhotite,and chalcopyrite with mesobands of dolomite+calcite+diopside+quartz and/or chlorite+sericite+quartz.The blastooolitic,blastopelletoid blastocolloidal and blastopsammitic textures,and blasobedding structures which most likely represent primary sedimentation are often observed in these BIF facies.The interbedded host rocks with the BIFs mainly are the pyroxene-amphibole rocks and the banded or impure dolostones,and also contain banded or laminated structures,and lepido-gra-noblastic,nematoblastic and/or blastoclastic textures.Compositionally,the main host rocks,the pyroxene-amphibole rocks contain basic-intermediate SiO_2(~54.00 wt.%),CaO(~14.19 wt.%),MgO(~9.68 wt.%)and Al_2O_3(~8.49 wt.%)with a positive correlation between Al_2O_3 and TiO_2.The UCC-like Zr and Hf abundances,high Ba content andεNd(t)value(^-5.99)as well as the ratios of La/YbPAAS(0.17~1.00),δEuPAAS(0.88~1.12)andδCePAAS(0.93~1.13)commonly reveal that the protoliths to this type rocks are hydrogenic with a large contribution of terrigenous sediments and minor hydrothermal input.The high CaO+MgO+LOI contents and the extremely low trace element and REEconcentrations as well as the ratios of Y/Ho(44~45),δEuPAAS(1.13~1.57)andδCePAAS(0.69~0.98)reflect a marine origin with minor terrigenous materials for the banded or impure dolostones.Moreover,this type rocks also account for a negativeεNd(t)value(^-7.49).The oxide facies BIF is dominated by Fe_2O_3+FeO(~75.59wt.%)and SiO_2(~20.47 wt.%)with aεNd(t)value of^-6.10.The variable contents in Al_2O_3,TiO 2,K2O,Na2O,Zr,Hf and∑REE,and variable ratios of Y/Ho(24~39)andδEuPAAS(0.86~11.07)suggest the precursor sediments to this facies BIF are admixtures of sea-floor hydrothermal fluids and seawaters with minor involvement of detrital components.Compared to the oxide facies BIF,the silicate-oxide facies BIF is lower in Fe_2O_3+Fe O(~39.81wt.%)and Ba but higher in SiO_2(~42.54 wt.%),Al2O3(~3.60 wt.%),TiO_2(~0.19 wt.%),MgO(~1.12 wt.%),CaO(~9.06 wt.%),K_2O(~0.98 wt.%),Mn and Zr.The ratios of Y/Ho(25~34),La/YbPAAS(0.14-0.74)andδEuPAAS(0.91~1.12)most likely are linked to higher degree of detrital contamintants.While the sulfide-caronate facies BIF is main but variable in Fe_2O_3+Fe O(15.79~57.91 wt.%),SiO 2(0.54~61.52 wt.%),MgO(0.12~16.09wt.%),CaO(0.17~23.41 wt.%)and LOI(8.28-30.06 wt.%).The generally low contents in trace elements(including REE)except for an obvious enrichment in Pb,and the positive Ce anomalies(δCePAAS=1.04~1.95)and negative Pr anomalies(δPrPAAS=0.67~0.93),as well as the variable ratios ofδEuPAAS(0.72~1.71),La/YbPAAS(0.26~1.60)and Y/Ho(26~57)suggest that the precursors to the sulfide-carbonate facies BIF mainly are metalliferious sediments from deep-marine hydrotheral source with minor detrital components.The T2DM ages(ca.2.0 Ga)imply that the Shilu BIFs and interbedded host rocks contain a component with Paleoproterozoic crustal residence age due to a significant crustal accretion event at ca.2.0 Ga in Hainan Island.In connection with the petrographical and mineralogical relationship,we conclude that the precursor precipitates to the Shilu BIFs are variable degree of admixtures of the Fe-Co-Cu-(Si)-rich hydrothermal fluids and detrital components from seawater and fresh water carring continental landmass;whereas the protolith to the main interbedded host rocks,i.e.the pyroxene-amphibole rocks,most likely was terrigenous,fine-grained clastic-sediments but with significant input of hydrothermal fluids in a seawater environment.As a result,a continent marginal marine basin is proposed for deposition of the Shilu BIFs and interbedded host rocks.Sea-level fluctuations caused by marine transgression–regressions possibly contributed to changes in the composition and varied input of the terrigenous sediments. 展开更多
关键词 Metamorphosed Neoproterozoic Lake Superior-type BIFs protoliths continent marginal marine basin Shilu Fe-polymetallic ore deposit hainan province of South China
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Recommendations for Construction and Management of Ecological Public Welfare Forest in Hainan Province
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作者 Yang XUE Renhui HONG +3 位作者 Dunxi LI Zhipan LIN Xiaoyan WANG Shaofeng SU 《Asian Agricultural Research》 2016年第2期58-60,63,共4页
This paper firstly evaluated ecological service functions of ecological public welfare forest in Hainan Province. Then,it introduced value structure and existing problems of ecological service functions. Focusing on o... This paper firstly evaluated ecological service functions of ecological public welfare forest in Hainan Province. Then,it introduced value structure and existing problems of ecological service functions. Focusing on optimization and adjustment of scale and distribution of ecological public welfare forest,it came up with recommendations for construction and management of ecological public welfare forest in Hainan Province. 展开更多
关键词 hainan province ECOLOGICAL public WELFARE forest Evaluation of ECOLOGICAL service functions CONSTRUCTION and MANAGEMENT RECOMMENDATIONS
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