Conditional nonlinear optimal perturbation (CNOP) obtained by the ensemble-based calculation method is employed to find possible sensitive areas for improving 48-h or more than 48-h tropical cyclone (TC) track predict...Conditional nonlinear optimal perturbation (CNOP) obtained by the ensemble-based calculation method is employed to find possible sensitive areas for improving 48-h or more than 48-h tropical cyclone (TC) track predictions in several cases affecting China in 2007. These sensitive areas are examined by observing system simulation experiments (OSSEs). Results show that these sensitive areas improve TC track predictions for 48 h or more to different extents. Further analysis is performed to determine the distribution characteristics of sensitive areas in these cases. Results show that areas south of Luzon and over surrounding oceans are significant for 48-h or more than 48-h TC track predictions, especially 60-h to 72-h track predictions. Areas over oceans north or east to Taiwan Island seem to be secondary sensitive for 48-h or more than 48-h TC track predictions.展开更多
The edible rose was planted on trial in Hainan under the tropical oceanic climate environment according to its botanic characteristics and growth habit. A set of cultural practices suitable for the edible rose planted...The edible rose was planted on trial in Hainan under the tropical oceanic climate environment according to its botanic characteristics and growth habit. A set of cultural practices suitable for the edible rose planted in Hainan was summarized, including land selection, land preparation, variety selection, planting requirements, field management, pruning, flowering regulation, and control of pests and diseases.展开更多
This paper describes results of the fluxes of momentum , sensible heat and latent heat for the West Pacific Tropical Ocean Area ( 127 ° E - 150 ° E , 5 ° N -3 ° S ). The data were collected by the ...This paper describes results of the fluxes of momentum , sensible heat and latent heat for the West Pacific Tropical Ocean Area ( 127 ° E - 150 ° E , 5 ° N -3 ° S ). The data were collected by the small tethered balloon sounding system over this ocean area including 6 continuous stations (140 ° E. 0 ° ; 145 ° E, 0 ° ; 150 ° E, 0 ° ; 140° E, 5 ° N; 145 ° E, 5° N and 150 ° E, 5 ° N) from 11 October to 15 December, 1986 . These fluxes were calculated by the semiempirical flux-profile relationships of Monin-Obukhov similarity theory using these observed data. The results show that for this tropical ocean area the drag coefficient CD is equal to (1.53 ± 0.25) × 10 3 and the daily mean latent flux Hl is greater than its daily mean sensible flux HV by a factor of about 9.展开更多
In this paper, the characteristics of change in the Antarctic sea ice area are analysed by using the observed data from 1973 1986. The analysed results show that the monthly and annual change of the Antarctic sea i...In this paper, the characteristics of change in the Antarctic sea ice area are analysed by using the observed data from 1973 1986. The analysed results show that the monthly and annual change of the Antarctic sea ice area is obvious, the biggest change value is in 160°E 120°W and 60°W 100°E, the smallest value is in 110°E 160°E and 120°W 60°W. The relation between the Antarctic sea ice area and the Sea Surface Temperature(SST) in tropical Pacific is close, and the relation between the Antarctic sea ice area in each longitude belt and SST in tropical Pacific shows a clear difference. It is obvious that the Antarctic sea ice areas in 0° 90°E and 100°E 110°W have a different feedbacking relation with SST in the tropical Pacific. The notable relationship occurs in the 3 4 and 41 45 months, that quite tallies with the occurrence of El Nino.展开更多
The use of Infrared Thermal Scanners proved to be very useful in lots of applications. Using different color palettes, temperatures can be well-represented in the resulting image. However, most color palettes in hot t...The use of Infrared Thermal Scanners proved to be very useful in lots of applications. Using different color palettes, temperatures can be well-represented in the resulting image. However, most color palettes in hot tropical places like the Philippines are unsuitable since the ambient temperature is almost the same as the scanned object or person. This study evaluates twelve (12) known and used color palettes in the market to determine the most suitable for tropical places using the edge/border tracing algorithms Sobel-Feldman and Laplacian. The result shows that color palettes with the most colors produce more noise, making it difficult to distinguish the object scanned from the background. On the other hand, color palettes with three or fewer contrasting colors produce crisp and more detailed results. This study helps developers and researchers efficiently use color combinations suitable for hot weather for an effective thermal scanning and image representation.展开更多
In this paper, by using ocean surface temperature data(COADS), the study is made of the characteristics of the monthly and annual changes of the SST in the tropical western Pacific and Indian Oceans, which have impo...In this paper, by using ocean surface temperature data(COADS), the study is made of the characteristics of the monthly and annual changes of the SST in the tropical western Pacific and Indian Oceans, which have important influences on the climate change of the whole globe and the relation between ENSO(El Nio Southern Oscillation) and the Antarctic ice area is also discussed. The result indicates that in the tropical western Pacific and the Indian Oceans the change of Sea Surface Temperture(SST) is conspicuous both monthly and annaully, and shows different change tendency between them. This result may be due to different relation in the vibration period of SST between the two Oceans. The better corresponding relationship is obvious in the annual change of SST in the tropical Indian Ocean with the occurrence El Nio and La Nia. The change of the SST in the tropical western Pacific and the tropical Indian Oceans has a close relation to the Antarctic ice area, especially to the ice areas in the eastern south Pole and Ross Sea, and its notable correlative relationship appears in 16 months when the SST of the tropical western Pacific and the Indian Oceans lag back the Antarctic ice area.展开更多
Introduction: The Adult Onset Still’s Disease (ASD) is a systemic auto-inflammatory affection of unknown cause seldom described in sub-Saharan Africa. We report 3 observations of ASD illustrating the diagnostic and t...Introduction: The Adult Onset Still’s Disease (ASD) is a systemic auto-inflammatory affection of unknown cause seldom described in sub-Saharan Africa. We report 3 observations of ASD illustrating the diagnostic and therapeutic difficulties of this affection in our areas. Observation 1: Our first patient is a 56 years old schoolteacher presenting an ASD in its chronic articular form. She had been followed for an inflammatory arthralgia for 10 years and of the pharyngal pains without exact diagnosis. She presented ASD’s criteria of Yamaguchi and of Fautrel. The prednisone was begun at the dose of 0.8 mg/kg/day with fast appearance of a progressive muscular weakness. Use of methotrexate at a rate of 15 mg per week, associated with low dose of prednisone was effective in long-term without any flare of the disease so far. Observation 2: Our second patient is a 30 years old dressmaker presenting an ASD in its complicated systemic form of lymphohistiocytic activation syndrome. She validated the criteria of Yamaguchi and Fautrel for ASD. She also presented resistance to corticosteroid therapy. The evolution was marked by a hospital-acquired septicemia and a multi-organ failure leading to death. The diagnosis was retrospectively confirmed after that, with the low level of the glycosylated ferritin serum value. Observation 3: The third patient is a 22 years old Guinean student who presented prolonged fever and inflammatory polyarthralgia without articular deformation. He had been misdiagnosed for ASD with diagnostic wandering of several months. He was treated successfully with prednisone after set up of ASD diagnosis according common criteria. Corticosteroid therapy was stopped after 8 months without any relapse noted so far. Conclusion: Caring for ASD is difficult in our context mainly because of high cost of several explorations needed to set up its exact diagnosis while making differential one. Evolution under corticosteroid therapy is usually favorable but diagnostic delay may lead to severe complications and death.展开更多
The integrated value of the ecological function of tropical forests in the central mountainous areas of Hainan Island was 33.064 8 billion yuan/a in 2010(soil improvement,soil consolidation,soil nutrient maintenance,w...The integrated value of the ecological function of tropical forests in the central mountainous areas of Hainan Island was 33.064 8 billion yuan/a in 2010(soil improvement,soil consolidation,soil nutrient maintenance,water storage and moisture regulation,water purification,carbon sequestration,oxygen releasing,air purification,biodiversity conservation,eco-tourism),equivalent to 16.1%of GDP in Hainan Province this year(205.212 billion yuan).The tropical forests in the central mountainous areas of Hainan Island make great contribution to Hainan Island's ecology,and play an important role in maintaining the stability of the ecological environment in Hainan Island.Through the understanding of major ecological function value of tropical forests,it is necessary to make people cherish the tropical forests in the central ecological function conservation areas of Hainan Province,and spontaneously throw themselves into the ecological environment protection and construction,to promote the rapid and sustainable development of construction in Hainan Province as an international tourism island.展开更多
The Keta Lagoon and its catchment areas in Ghana are influenced by intensive agriculture and the use of agro-chemicals. It has therefore, become necessary to assess the quality of water in the lagoon and the surroundi...The Keta Lagoon and its catchment areas in Ghana are influenced by intensive agriculture and the use of agro-chemicals. It has therefore, become necessary to assess the quality of water in the lagoon and the surrounding fresh water aquifers. In this study, a water quality index (WQI), indicating the water quality has been adopted. The WQI was determined on a basis of various physico-chemical parameters like pH, conductivity, turbidity, dissolved oxygen, calcium, magnesium, chloride, nitrates, ammonium and sodium. The index was used both for tracking changes at one site over time, and for comparisons among sites. The WQI was also employed to wells used for irrigation on farms along the Keta Sand Spit as well as that of the Keta Lagoon Complex and its surrounding floodplains, in order to ascertain the quality of water for public and livestock consumption, irrigation, recreation and other purposes. The WQI of the wells, Keta lagoon and its floodplains showed various degrees of poor water quality and therefore considered unsuitable for drinking and recreation. By WHO standards, this calls for intensive physical and chemical treatment of the water for human consumption.展开更多
[Objectivel The study aimed to assess the risk of tropical cyclones to wind farm operation in northem costal areas of Jiangsu Province. [Metbod] Based on tropical cyclone data during 1951 -2011 from nine national basi...[Objectivel The study aimed to assess the risk of tropical cyclones to wind farm operation in northem costal areas of Jiangsu Province. [Metbod] Based on tropical cyclone data during 1951 -2011 from nine national basic weather stations as well as wind data during 2005 -2007 de- termined by six gradient wind measurement towers in northern costal areas of Jiangsu Province, the spatial and temporal distribution of tropical cy- clones influencing northern coastal areas of Jiangsu Province were discussed firstly, and then the possible effects of tropical cyclones on wind farms in the northern costal areas were assessed, finally some suggestions about type selection and parameter design of wind turbines were proposed. Restult Annual average number of tropical cyclones influencing northern coastal areas of Jiangsu Province was 1.7, and the first two kinds of tropical cyclones were dominant in quantity, accounting for about 73% for total quantity. The quantity of tropical cyclones bringing substantial economic benefits to wind farms accounted for 87.7% of total quantity, with annual average quantity of 1.5. Maximum wind speed appearing every 50 years did not exceed 37.5 m/s, in accord with the national Grade-Ill standard for safe operation of wind turbines. 2.1% -3.8% of turbulence intensity ei- genvalues at a height of 70 m exceeded the maximum anti-turbulence intensity designed by IEC (0.16), and it is suggested that anti-turbulence in- tensity parameter of wind turbines in northem costal areas of East China should be changed to 0.31 -0.41. [ Conclusion] The research could provide scientific references for design and choice of wind turbines as well as operation and management of wind farms in the study region in future.展开更多
Bitterlich sampling is an extensively used technique in worldwide forest inventories. Although it has been proved that estimates of basal area from Bitterlich sampling are mathematically unbiased, its precision for in...Bitterlich sampling is an extensively used technique in worldwide forest inventories. Although it has been proved that estimates of basal area from Bitterlich sampling are mathematically unbiased, its precision for individual forest stands may be fairly poor. An extension of validation efforts to different forest biomes could therefore provide more comprehensive assessment and understanding of the Bitterlich sampling technique. In this study, this technique was quantitatively evaluated by using simulated sparse boreal forests and dense tropical forests from an empirical forest structure model (EFSM). Theoretical estimation of basal areas and practical estimation influenced by the hidden-tree effect were both compared with true basal areas of the simulated forests. The evaluation results indicated that: 1) Bitterlich sampling can yield acceptable accuracy and precision when the count number (CN) of trees was set to 10 for the studied boreal and tropical forests with distinct characteristics, 2) the theoretical estimation of basal area can be improved by increasing the CN values for both forests, and 3) when the hidden-tree effect is encountered, the accuracy for tropical forests will be decreased by increasing the CN values, whereas the accuracy for boreal forests can still be improved. Accordingly, a relatively high CN, at a reasonable cost, is recommended for sparse boreal forests to improve the accuracy of basal area estimation. In contrast, for dense tropical forests, a CN of ten is appropriate to mitigate the hidden-tree effect.展开更多
The realization of two management inventories in 2003 and 2020 on the same forest concession made it possible to characterize the floristic composition and to describe some structural parameters on three sites establi...The realization of two management inventories in 2003 and 2020 on the same forest concession made it possible to characterize the floristic composition and to describe some structural parameters on three sites established according to the period of exploitation. Due to the change in the orientation of the lines, it was noted that respectively 82 and 85 species from the first inventory are not found in the second and inversely. A total of 311 species were identified in 2003, compared to 314 in 2020. The density varies from 111 to 140 stems/ha for all the individuals, 19 to 25 for the main species and 15 to 20 for the most exploited species. The decrease in the basal area between the two phases of 12% for all the species and 13% for the main species on the site exploited before the first inventory indicates a persistence of the disturbance for years after logging. It is proposed to supplement the management plans decisions with annual measures based on more complete inventories and to ensure the application of reduced impact logging measures.展开更多
在国内外研究的基础上,对印太暖池区的沃克环流和厄尔尼诺-南方涛动(ENSO)、热带辐合带(ITCZ)等低纬过程的空间分布和随时间的变化规律及其研究方法进行初步归纳,并指出研究中存在的问题。本文论述了厄尔尼诺-南方涛动变率在全新世早期...在国内外研究的基础上,对印太暖池区的沃克环流和厄尔尼诺-南方涛动(ENSO)、热带辐合带(ITCZ)等低纬过程的空间分布和随时间的变化规律及其研究方法进行初步归纳,并指出研究中存在的问题。本文论述了厄尔尼诺-南方涛动变率在全新世早期及中世纪气候异常期(1 000~700 a BP)的晚期逐渐增强,介绍了热带辐合带在BA暖期(B?llingAller?d Warm Period)和前北方期(pre-Boreal,10.3~9.5 ka BP)的北移,以及在新仙女木事件(Younger Dryas Event,12.5~11.5 ka BP)和北大西洋冷期(距今7.5~5 ka BP)期间的南移。对低纬过程长时间尺度轨道周期的探讨表明,末次冰盛期赤道东太平洋出现了较偏南的热带辐合带锋面系统,甚至在1.65 Ma冰期,热带辐合带也有快速南移的证据。海洋沉积的粒度、黏土矿物、陆源粉尘、元素和同位素、有孔虫分析等研究方法在推测厄尔尼诺-南方涛动和热带辐合带位移中有很好的应用,建议以陆源生态系统对气候的响应为切入点、以孢粉为手段来探讨陆源植被、气候、火灾和海-陆大气环流等低纬过程的变化特征,进而反演沃克环流(或厄尔尼诺-南方涛动)演化和热带辐合带位移的影响。展开更多
Based on tropical cyclone (TC) data for the period 1949 to 2008 and following the Gumbe-Imethod, Pearson-Ⅲ method and determinacy method, this article estimates the possible minimum centralpressure of TCs affecting s...Based on tropical cyclone (TC) data for the period 1949 to 2008 and following the Gumbe-Imethod, Pearson-Ⅲ method and determinacy method, this article estimates the possible minimum centralpressure of TCs affecting southern Fujian where a nuclear power will be located. Results show that theobserved minimum central pressure of TCs agrees well with the results determined with the methods aboveand there is little difference between them (the minimum central pressure is 867.4 hPa and 868.1 hPa,respectively, in a 1,000-yr return period). Established with the theory of atmospheric dynamics, thedeterminacy method yields a result of 867.28 hPa/1000 years, only a little smaller than the result of theprobability method. Because of randomicity in parameter adjustment with the Pearson-Ⅲ method whereasthe determinacy method is theoretically solid and its estimates are the smallest of the three methods, it istherefore reasonable, for security and conservative concerns, to adopt the result determined with thedeterminacy method as the possible maximum intensity of TC (with the central pressure being 867.28 hPa ina 1,000-yr return period).展开更多
Objective:To understand the epidemic characters of COVID-19 epidemic in Hainan province of tropical China and provid evidences for the prevention and control of the epidemic.Methods:Data on the COVID-19 epidemic colle...Objective:To understand the epidemic characters of COVID-19 epidemic in Hainan province of tropical China and provid evidences for the prevention and control of the epidemic.Methods:Data on the COVID-19 epidemic collected from Health Commission of Hainan Province were analyzed by using the methods of retrospective descriptive epidemiology.Results:From January 22nd to February 21st,2020,COVID-19 was diagnosed in 168 confirmed cases(including 8 severe cases)in Hainan Province with the temporary fatality rate of 2.38%of 4 deaths,and 96 cases discharged from hospital,with the cure rate of 57.14%.The cases were distributed in altogether 15 cities and counties in Hainan Province,among which 121 cases were distributed in Sanya,Haikou,Danzhou and Wanning,accounting for 72.02%of the total number of cases.Cases in Sanya City were mainly found in Tianya district and Jiyang district,accounting for 69.81%of the total number of cases in Sanya.Cases in Haikou City were mainly found in Qiongshan district and Xiuying district,accounting for 72.5%of the total number of cases in Haikou.Among the patients,there were 81 males and 87 females,with a male-to-female ratio of 1.1;the youngest age was 3 months,the oldest was 79 years old,80%of the patients were in the age group of 30 to 69 years old,and the number of children and adolescents under 20 years old were relatively low.Conclusion:The daily number of new confirmed cases showed a gradual downward trend in Hainan province,and the epidemic situation was in transition from imported to local renewal,mainly in close contact between family members.With the increase of personnel mobility such as the resumption of work by enterprises and the return of migrant workers to the island,there is a risk of agglomeration epidemic.Prevention and control work in urban and rural areas should take a two-pronged approach.Amid preventing imported cases,more proactive measures should be taken to prevent and control the spread of local cases.展开更多
基金supported by the Foundation of Shanghai Typhoon Institute of China Meteorological Administration (Grant No. 2008ST02)the National Basic Research Program of China (Grant No. 2009CB421500)
文摘Conditional nonlinear optimal perturbation (CNOP) obtained by the ensemble-based calculation method is employed to find possible sensitive areas for improving 48-h or more than 48-h tropical cyclone (TC) track predictions in several cases affecting China in 2007. These sensitive areas are examined by observing system simulation experiments (OSSEs). Results show that these sensitive areas improve TC track predictions for 48 h or more to different extents. Further analysis is performed to determine the distribution characteristics of sensitive areas in these cases. Results show that areas south of Luzon and over surrounding oceans are significant for 48-h or more than 48-h TC track predictions, especially 60-h to 72-h track predictions. Areas over oceans north or east to Taiwan Island seem to be secondary sensitive for 48-h or more than 48-h TC track predictions.
基金Supported by the Special Fund for the Spark Industry Strip of Hainan Province(HNXH201401)
文摘The edible rose was planted on trial in Hainan under the tropical oceanic climate environment according to its botanic characteristics and growth habit. A set of cultural practices suitable for the edible rose planted in Hainan was summarized, including land selection, land preparation, variety selection, planting requirements, field management, pruning, flowering regulation, and control of pests and diseases.
文摘This paper describes results of the fluxes of momentum , sensible heat and latent heat for the West Pacific Tropical Ocean Area ( 127 ° E - 150 ° E , 5 ° N -3 ° S ). The data were collected by the small tethered balloon sounding system over this ocean area including 6 continuous stations (140 ° E. 0 ° ; 145 ° E, 0 ° ; 150 ° E, 0 ° ; 140° E, 5 ° N; 145 ° E, 5° N and 150 ° E, 5 ° N) from 11 October to 15 December, 1986 . These fluxes were calculated by the semiempirical flux-profile relationships of Monin-Obukhov similarity theory using these observed data. The results show that for this tropical ocean area the drag coefficient CD is equal to (1.53 ± 0.25) × 10 3 and the daily mean latent flux Hl is greater than its daily mean sensible flux HV by a factor of about 9.
文摘In this paper, the characteristics of change in the Antarctic sea ice area are analysed by using the observed data from 1973 1986. The analysed results show that the monthly and annual change of the Antarctic sea ice area is obvious, the biggest change value is in 160°E 120°W and 60°W 100°E, the smallest value is in 110°E 160°E and 120°W 60°W. The relation between the Antarctic sea ice area and the Sea Surface Temperature(SST) in tropical Pacific is close, and the relation between the Antarctic sea ice area in each longitude belt and SST in tropical Pacific shows a clear difference. It is obvious that the Antarctic sea ice areas in 0° 90°E and 100°E 110°W have a different feedbacking relation with SST in the tropical Pacific. The notable relationship occurs in the 3 4 and 41 45 months, that quite tallies with the occurrence of El Nino.
文摘The use of Infrared Thermal Scanners proved to be very useful in lots of applications. Using different color palettes, temperatures can be well-represented in the resulting image. However, most color palettes in hot tropical places like the Philippines are unsuitable since the ambient temperature is almost the same as the scanned object or person. This study evaluates twelve (12) known and used color palettes in the market to determine the most suitable for tropical places using the edge/border tracing algorithms Sobel-Feldman and Laplacian. The result shows that color palettes with the most colors produce more noise, making it difficult to distinguish the object scanned from the background. On the other hand, color palettes with three or fewer contrasting colors produce crisp and more detailed results. This study helps developers and researchers efficiently use color combinations suitable for hot weather for an effective thermal scanning and image representation.
文摘In this paper, by using ocean surface temperature data(COADS), the study is made of the characteristics of the monthly and annual changes of the SST in the tropical western Pacific and Indian Oceans, which have important influences on the climate change of the whole globe and the relation between ENSO(El Nio Southern Oscillation) and the Antarctic ice area is also discussed. The result indicates that in the tropical western Pacific and the Indian Oceans the change of Sea Surface Temperture(SST) is conspicuous both monthly and annaully, and shows different change tendency between them. This result may be due to different relation in the vibration period of SST between the two Oceans. The better corresponding relationship is obvious in the annual change of SST in the tropical Indian Ocean with the occurrence El Nio and La Nia. The change of the SST in the tropical western Pacific and the tropical Indian Oceans has a close relation to the Antarctic ice area, especially to the ice areas in the eastern south Pole and Ross Sea, and its notable correlative relationship appears in 16 months when the SST of the tropical western Pacific and the Indian Oceans lag back the Antarctic ice area.
文摘Introduction: The Adult Onset Still’s Disease (ASD) is a systemic auto-inflammatory affection of unknown cause seldom described in sub-Saharan Africa. We report 3 observations of ASD illustrating the diagnostic and therapeutic difficulties of this affection in our areas. Observation 1: Our first patient is a 56 years old schoolteacher presenting an ASD in its chronic articular form. She had been followed for an inflammatory arthralgia for 10 years and of the pharyngal pains without exact diagnosis. She presented ASD’s criteria of Yamaguchi and of Fautrel. The prednisone was begun at the dose of 0.8 mg/kg/day with fast appearance of a progressive muscular weakness. Use of methotrexate at a rate of 15 mg per week, associated with low dose of prednisone was effective in long-term without any flare of the disease so far. Observation 2: Our second patient is a 30 years old dressmaker presenting an ASD in its complicated systemic form of lymphohistiocytic activation syndrome. She validated the criteria of Yamaguchi and Fautrel for ASD. She also presented resistance to corticosteroid therapy. The evolution was marked by a hospital-acquired septicemia and a multi-organ failure leading to death. The diagnosis was retrospectively confirmed after that, with the low level of the glycosylated ferritin serum value. Observation 3: The third patient is a 22 years old Guinean student who presented prolonged fever and inflammatory polyarthralgia without articular deformation. He had been misdiagnosed for ASD with diagnostic wandering of several months. He was treated successfully with prednisone after set up of ASD diagnosis according common criteria. Corticosteroid therapy was stopped after 8 months without any relapse noted so far. Conclusion: Caring for ASD is difficult in our context mainly because of high cost of several explorations needed to set up its exact diagnosis while making differential one. Evolution under corticosteroid therapy is usually favorable but diagnostic delay may lead to severe complications and death.
文摘The integrated value of the ecological function of tropical forests in the central mountainous areas of Hainan Island was 33.064 8 billion yuan/a in 2010(soil improvement,soil consolidation,soil nutrient maintenance,water storage and moisture regulation,water purification,carbon sequestration,oxygen releasing,air purification,biodiversity conservation,eco-tourism),equivalent to 16.1%of GDP in Hainan Province this year(205.212 billion yuan).The tropical forests in the central mountainous areas of Hainan Island make great contribution to Hainan Island's ecology,and play an important role in maintaining the stability of the ecological environment in Hainan Island.Through the understanding of major ecological function value of tropical forests,it is necessary to make people cherish the tropical forests in the central ecological function conservation areas of Hainan Province,and spontaneously throw themselves into the ecological environment protection and construction,to promote the rapid and sustainable development of construction in Hainan Province as an international tourism island.
文摘The Keta Lagoon and its catchment areas in Ghana are influenced by intensive agriculture and the use of agro-chemicals. It has therefore, become necessary to assess the quality of water in the lagoon and the surrounding fresh water aquifers. In this study, a water quality index (WQI), indicating the water quality has been adopted. The WQI was determined on a basis of various physico-chemical parameters like pH, conductivity, turbidity, dissolved oxygen, calcium, magnesium, chloride, nitrates, ammonium and sodium. The index was used both for tracking changes at one site over time, and for comparisons among sites. The WQI was also employed to wells used for irrigation on farms along the Keta Sand Spit as well as that of the Keta Lagoon Complex and its surrounding floodplains, in order to ascertain the quality of water for public and livestock consumption, irrigation, recreation and other purposes. The WQI of the wells, Keta lagoon and its floodplains showed various degrees of poor water quality and therefore considered unsuitable for drinking and recreation. By WHO standards, this calls for intensive physical and chemical treatment of the water for human consumption.
基金Supported by the Science and Technology Planning Project of Lianyungang City,China(SH0916,SH1207)
文摘[Objectivel The study aimed to assess the risk of tropical cyclones to wind farm operation in northem costal areas of Jiangsu Province. [Metbod] Based on tropical cyclone data during 1951 -2011 from nine national basic weather stations as well as wind data during 2005 -2007 de- termined by six gradient wind measurement towers in northern costal areas of Jiangsu Province, the spatial and temporal distribution of tropical cy- clones influencing northern coastal areas of Jiangsu Province were discussed firstly, and then the possible effects of tropical cyclones on wind farms in the northern costal areas were assessed, finally some suggestions about type selection and parameter design of wind turbines were proposed. Restult Annual average number of tropical cyclones influencing northern coastal areas of Jiangsu Province was 1.7, and the first two kinds of tropical cyclones were dominant in quantity, accounting for about 73% for total quantity. The quantity of tropical cyclones bringing substantial economic benefits to wind farms accounted for 87.7% of total quantity, with annual average quantity of 1.5. Maximum wind speed appearing every 50 years did not exceed 37.5 m/s, in accord with the national Grade-Ill standard for safe operation of wind turbines. 2.1% -3.8% of turbulence intensity ei- genvalues at a height of 70 m exceeded the maximum anti-turbulence intensity designed by IEC (0.16), and it is suggested that anti-turbulence in- tensity parameter of wind turbines in northem costal areas of East China should be changed to 0.31 -0.41. [ Conclusion] The research could provide scientific references for design and choice of wind turbines as well as operation and management of wind farms in the study region in future.
文摘Bitterlich sampling is an extensively used technique in worldwide forest inventories. Although it has been proved that estimates of basal area from Bitterlich sampling are mathematically unbiased, its precision for individual forest stands may be fairly poor. An extension of validation efforts to different forest biomes could therefore provide more comprehensive assessment and understanding of the Bitterlich sampling technique. In this study, this technique was quantitatively evaluated by using simulated sparse boreal forests and dense tropical forests from an empirical forest structure model (EFSM). Theoretical estimation of basal areas and practical estimation influenced by the hidden-tree effect were both compared with true basal areas of the simulated forests. The evaluation results indicated that: 1) Bitterlich sampling can yield acceptable accuracy and precision when the count number (CN) of trees was set to 10 for the studied boreal and tropical forests with distinct characteristics, 2) the theoretical estimation of basal area can be improved by increasing the CN values for both forests, and 3) when the hidden-tree effect is encountered, the accuracy for tropical forests will be decreased by increasing the CN values, whereas the accuracy for boreal forests can still be improved. Accordingly, a relatively high CN, at a reasonable cost, is recommended for sparse boreal forests to improve the accuracy of basal area estimation. In contrast, for dense tropical forests, a CN of ten is appropriate to mitigate the hidden-tree effect.
文摘The realization of two management inventories in 2003 and 2020 on the same forest concession made it possible to characterize the floristic composition and to describe some structural parameters on three sites established according to the period of exploitation. Due to the change in the orientation of the lines, it was noted that respectively 82 and 85 species from the first inventory are not found in the second and inversely. A total of 311 species were identified in 2003, compared to 314 in 2020. The density varies from 111 to 140 stems/ha for all the individuals, 19 to 25 for the main species and 15 to 20 for the most exploited species. The decrease in the basal area between the two phases of 12% for all the species and 13% for the main species on the site exploited before the first inventory indicates a persistence of the disturbance for years after logging. It is proposed to supplement the management plans decisions with annual measures based on more complete inventories and to ensure the application of reduced impact logging measures.
文摘在国内外研究的基础上,对印太暖池区的沃克环流和厄尔尼诺-南方涛动(ENSO)、热带辐合带(ITCZ)等低纬过程的空间分布和随时间的变化规律及其研究方法进行初步归纳,并指出研究中存在的问题。本文论述了厄尔尼诺-南方涛动变率在全新世早期及中世纪气候异常期(1 000~700 a BP)的晚期逐渐增强,介绍了热带辐合带在BA暖期(B?llingAller?d Warm Period)和前北方期(pre-Boreal,10.3~9.5 ka BP)的北移,以及在新仙女木事件(Younger Dryas Event,12.5~11.5 ka BP)和北大西洋冷期(距今7.5~5 ka BP)期间的南移。对低纬过程长时间尺度轨道周期的探讨表明,末次冰盛期赤道东太平洋出现了较偏南的热带辐合带锋面系统,甚至在1.65 Ma冰期,热带辐合带也有快速南移的证据。海洋沉积的粒度、黏土矿物、陆源粉尘、元素和同位素、有孔虫分析等研究方法在推测厄尔尼诺-南方涛动和热带辐合带位移中有很好的应用,建议以陆源生态系统对气候的响应为切入点、以孢粉为手段来探讨陆源植被、气候、火灾和海-陆大气环流等低纬过程的变化特征,进而反演沃克环流(或厄尔尼诺-南方涛动)演化和热带辐合带位移的影响。
基金Natural Science Foundation of Fujian Province(2007J0122)Natural Science Foundation of China(90915002)
文摘Based on tropical cyclone (TC) data for the period 1949 to 2008 and following the Gumbe-Imethod, Pearson-Ⅲ method and determinacy method, this article estimates the possible minimum centralpressure of TCs affecting southern Fujian where a nuclear power will be located. Results show that theobserved minimum central pressure of TCs agrees well with the results determined with the methods aboveand there is little difference between them (the minimum central pressure is 867.4 hPa and 868.1 hPa,respectively, in a 1,000-yr return period). Established with the theory of atmospheric dynamics, thedeterminacy method yields a result of 867.28 hPa/1000 years, only a little smaller than the result of theprobability method. Because of randomicity in parameter adjustment with the Pearson-Ⅲ method whereasthe determinacy method is theoretically solid and its estimates are the smallest of the three methods, it istherefore reasonable, for security and conservative concerns, to adopt the result determined with thedeterminacy method as the possible maximum intensity of TC (with the central pressure being 867.28 hPa ina 1,000-yr return period).
文摘Objective:To understand the epidemic characters of COVID-19 epidemic in Hainan province of tropical China and provid evidences for the prevention and control of the epidemic.Methods:Data on the COVID-19 epidemic collected from Health Commission of Hainan Province were analyzed by using the methods of retrospective descriptive epidemiology.Results:From January 22nd to February 21st,2020,COVID-19 was diagnosed in 168 confirmed cases(including 8 severe cases)in Hainan Province with the temporary fatality rate of 2.38%of 4 deaths,and 96 cases discharged from hospital,with the cure rate of 57.14%.The cases were distributed in altogether 15 cities and counties in Hainan Province,among which 121 cases were distributed in Sanya,Haikou,Danzhou and Wanning,accounting for 72.02%of the total number of cases.Cases in Sanya City were mainly found in Tianya district and Jiyang district,accounting for 69.81%of the total number of cases in Sanya.Cases in Haikou City were mainly found in Qiongshan district and Xiuying district,accounting for 72.5%of the total number of cases in Haikou.Among the patients,there were 81 males and 87 females,with a male-to-female ratio of 1.1;the youngest age was 3 months,the oldest was 79 years old,80%of the patients were in the age group of 30 to 69 years old,and the number of children and adolescents under 20 years old were relatively low.Conclusion:The daily number of new confirmed cases showed a gradual downward trend in Hainan province,and the epidemic situation was in transition from imported to local renewal,mainly in close contact between family members.With the increase of personnel mobility such as the resumption of work by enterprises and the return of migrant workers to the island,there is a risk of agglomeration epidemic.Prevention and control work in urban and rural areas should take a two-pronged approach.Amid preventing imported cases,more proactive measures should be taken to prevent and control the spread of local cases.