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Bioconcentration of polycyclic aromatic hydrocarbons in roots of three mangrove species in Jiulong River Estuary 被引量:7
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作者 LUZhi-qiang ZHENGWen-jiao MALi 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第2期285-289,共5页
The polycyclic aromatic hydrocarbons(PAHs) concentrations were determined in the root of three mangrove species(Kandelia candel, Avicennia marina and Bruguiera gymnorrhiza) and their growing environment(sediment) in m... The polycyclic aromatic hydrocarbons(PAHs) concentrations were determined in the root of three mangrove species(Kandelia candel, Avicennia marina and Bruguiera gymnorrhiza) and their growing environment(sediment) in mangrove wetlands of Jiulong River Estuary, Fujian, China. The total PAHs(16 parent PAHs) in mangrove sediments ranged from 193.44 to 270.53 ng/g dw, with a mean value of 231.76±31.78 ng/g dw. Compared with other mangrove and coastal marine sediments, the PAHs concentrations of all the sampling areas in this study were at relatively lower level. The total PAHs(13 parent PAHs) values varied from 30.83 to 62.73 ng/g dw in mangrove roots. Benzo[a]pyrene(five-ring), fluoranthene(four-ring) and pyrene(four-ring) dominated in mangrove sediments. Based on ratios of phenathrene/anthracene, fluoranthene/pyrene and fluoranthene/pyrene + fluoranthene, the main possible sources of surface sediment PAHs were identified as grass, wood or coal combustion for mangrove wetlands of Jiulong River Estuary. Naphthalene(two-ring) and phenathrene(three-ring) were the most abundant compounds in mangrove roots. Sediment-to-vegetation bioconcentration factors(BCF SV s) were calculated and their relationships with PAHs' physico-chemical properties were investigated. The average BCF SV s of PAHs for three mangrove species roots were almost all under the level of 1 except for naphthalene. Good linear relationship between BCF SV values for mangrove roots and PAHs water solubility, octanol-water partitioning coefficients was derived in present study. The solubility and the octanol-water partition coefficient were proved to be good predictors for the accumulation of PAHs in mangrove roots, respectively. 展开更多
关键词 MANGROVE PAHS jiulong River Estuary bioconcentration factors
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The study on three-dimensional numerical model and fronts of the Jiulong Estuary and the Xiamen Bay 被引量:3
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作者 LUO Zhibin PAN Weiran +1 位作者 LI Li ZHANG Guorong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2012年第4期55-64,共10页
Applying the methods of on-site observation and dynamic model, the research on the fronts at the Jiulong Estuary has been carried out, during which spatial and temporal distribution, dynamic characteristics and format... Applying the methods of on-site observation and dynamic model, the research on the fronts at the Jiulong Estuary has been carried out, during which spatial and temporal distribution, dynamic characteristics and formation mechanism of salinity fronts are analyzed and discussed. The research shows that the estuarine fronts mainly lie in the area from the Jiyu Islet to the Haimen Island, outside of Yuweizai to Hulishan cross-section, the near coast of Yuweizai and the south of the Songyu-Gulangyu Channel. The fronts in the former two regions are formed directly by plume, while the one near the coast of Yuweizai is a tidal intrusion front caused by flood current and the one at the south of the Songyu-Gulangyu Channel is the result of current shear transformation. Under normal circumstances, fresh water of the Jiulong River mainly influences the inside of the Xiamen Bay, and when it is in typhoon seasons, plume front can affect the Taiwan Strait and has an effect on the biogeochemical Drocesses in the strait. 展开更多
关键词 jiulong Estuary Xiamen Bay three-dimensional numerical model FRONTS
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Dynamics of phytoplankton communities in the Jiangdong Reservoir of Jiulong River,Fujian,South China 被引量:4
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作者 田永强 黄邦钦 +2 位作者 俞超超 陈能汪 洪华生 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第2期255-265,共11页
Phytoplankton blooms occurring in the Jiangdong Reservoir of Jiulong River,Fujian Province,South China,are a potential source of contamination of the drinking water of Xiamen(Amoy)City.To understand the main factors g... Phytoplankton blooms occurring in the Jiangdong Reservoir of Jiulong River,Fujian Province,South China,are a potential source of contamination of the drinking water of Xiamen(Amoy)City.To understand the main factors governing phytoplankton composition and succession,we sampled phytoplankton and measured environmental parameters in the reservoir,weekly or biweekly from Jan.2010 to Feb.2012.We identifi ed 123 species of phytoplankton from 7 phyla and 74 genera.The major phyla were Chlorophyta,Bacillariophyta,Cryptophyta,Cyanophyta,and Dinophyta.The main trend in the succession of phytoplankton was from prevalence of Cryptophyta-Bacillariophyta communities to those of Chlorophyta-Cyanophyta.High cell concentrations of Cryptophyta,predominantly Komma caudate,Cryptomonas marssonii,and Cryptomonas erosa,were present in winter,associated with low river discharge and cold water.Bacillariophyta,primarily Cyclotella meneghiniana,Aulacoseira granulata,and Aulacoseira granulata var.angustissima,dominated in early spring,coinciding with high turbulence and low irradiance.During early summer and autumn,Chlorophyta,comprising Scenedesmus quadricauda,Dictyosphaerium ehrenbergianum,and Pandorina sp.were prevalent during conditions of warmer water temperatures and low turbulence.Cyanophyta,with dominance of Pseudanabaena mucicola,Merismopedia tenuissima and Raphidiopsis sp.increased throughout the summer,coinciding with higher water temperatures and lower nutrient concentrations.Dinophyta content was occasionally high during winter and summer.Peridiniopsis penardii(Dinophyta)bloomed during winter 2009,with a persistently high biomass recorded into early spring.Canonical correspondence analysis indicated that phytoplankton communities were infl uenced by river discharge,irradiance,water temperature,and nutrient concentrations. 展开更多
关键词 phytoplankton composition community succession environmental factors canonical correspondence analysis (CCA) jiulong River
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Characteristics of nutrients in the Jiulong River and its impact on Xiamen Water, China 被引量:3
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作者 陈宝红 暨卫东 +4 位作者 陈金民 林彩 黄海宁 霍云龙 纪贤标 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第5期1055-1063,共9页
Water samples were collected at 20 sites on 4 occasions in 2009 (twice in May, and once in both August and November) along the Jiulong River, South China to examine how nutrient inputs from the Jiulong River could a... Water samples were collected at 20 sites on 4 occasions in 2009 (twice in May, and once in both August and November) along the Jiulong River, South China to examine how nutrient inputs from the Jiulong River could affect the nutrient status of the Xiamen Water. Samples were analyzed for nitrite (NO2-N), nitrate (NO3-N), ammonium (NH4-N), phosphate (PO4-P), silicate (SiO3-Si), salinity, and temperature, to determine the nutrient and trophic status of the river. The results indicate that nutrients are derived mainly from river runoff. NO3-N was the main form of DIN in most parts of the river. In addition, NO3-N, DIN, and SiO3-Si behave conservatively. There is a surplus of DIN and SiO3-Si in the river, and PO4-P is a limitation on phytoplankton growth. The concentration of DIN is typically above 0.60 mg/dm3, and higher than 1.00 mg/dm3 in most parts of the river. The concentration of PO4-P is typically above 0.02 mg/dm3, while the concentration of SiO3-Si is higher than 1.00 rag/din3. Between 2003 and 2008, samples were collected 3 times per year (May, August and November) at 27 sites in the Xiamen Water and analyzed for NO2-N, NO3-N, NH4-N, PO4-P, salinity, and temperature. We discovered that the Jiulong River was the key source of DIN into the Xiamen Water, but not PO4-P, indicating the reason of the N/P molar ratio imbalance in the Xiamen Water. In the future, the effects of high DIN concentrations on the phytoplankton communities and marine ecosystems of the Xiamen Water shall be studied. 展开更多
关键词 NUTRIENT molar ratio EUTROPHICATION N enrichment the jiulong River
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Late Quaternary diatom and sea level changes in estuarine plain of the Jiulong River 被引量:2
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作者 Chen Wenrui, (State Pilot Laboratory of Coast and Island Exploitation, Naning University, Naning 210093, China)Lan Dongzhao and Chen Chenghui (Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1998年第4期509-518,共10页
Four units and twenty-four zones of diatom have been discerned in the Borehole ZK5 in the estuarine plain of the Jiulong River, Fujian Province. Comprehensive analysis of these, together with microbiological assemblag... Four units and twenty-four zones of diatom have been discerned in the Borehole ZK5 in the estuarine plain of the Jiulong River, Fujian Province. Comprehensive analysis of these, together with microbiological assemblages and age determinations in some other boreholes, shows that during the Late Wurm Glacial, sea level of the study area rose and fell frequently, but had principally been in the environments of estuary-bay. This mainly resulted from the tectonic subouction. In this period 3 low sea levels occurred. at 18, 16 and 12 kaBP respectively. During Holocene, sea weter intruded massively and the sea level over the transgnaion maximum had been 5-10 m higher than that of the present. 展开更多
关键词 Late Quaternary DIATOM sea level change estuarine plain the jiulong River
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Preliminary study on the distribution of nutrients, organic matter, trace metals in sea surface microlayer in Xiamen Bay and Jiulong Estuary 被引量:4
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作者 Hong Huasheng and Lin Jie Department of Oceanography, Xiamen University. Xiamen, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1990年第1期81-90,共10页
The enrichment of nutrients (Noa-, Noa-, PO43-), suspended particles, organic matter (POC, PON,DOC) , and trace metals (Cu, Ni, Cd) was determined in the sea surface microlayer of Xiamen Bay and Jiulong Estuary. The m... The enrichment of nutrients (Noa-, Noa-, PO43-), suspended particles, organic matter (POC, PON,DOC) , and trace metals (Cu, Ni, Cd) was determined in the sea surface microlayer of Xiamen Bay and Jiulong Estuary. The mean enrichment factors ([Xi]microlayer/[Xi ]15cm in depth) mostly ranged between 1 . 0 and 2. 0. The dissolved forms were the major forms of the components measured, the enrichment of dissolved organic matter and suspended particles could lead to the changes in the total amount and speciation of nutrients and trace metals. No correlation was observed between sample concentrations, speciation, enrichment factors and sample locations. However, some evidence shows that these parameters are correlated with sea state, indicating the complexity and dynamic nature of the sea surface microlayer. 展开更多
关键词 Preliminary study on the distribution of nutrients trace metals in sea surface microlayer in Xiamen Bay and jiulong Estuary BAY
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ENVIRONMENTAL CHANGES SINCE LATE PLEISTOCENE IN ESTUARINE PLAIN OF JIULONG RIVER, FUJIAN PROVINCE 被引量:1
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作者 陈文瑞 蓝东兆 +1 位作者 陈承惠 朱大奎 《Chinese Geographical Science》 SCIE CSCD 1997年第4期375-382,共8页
Based on the evidences of lithostratigraphy, palynology, micropaleontolopy and geochronology, paleoenvironments since the Late Pleistocene in the study area have been reconstructed. One of the most important inference... Based on the evidences of lithostratigraphy, palynology, micropaleontolopy and geochronology, paleoenvironments since the Late Pleistocene in the study area have been reconstructed. One of the most important inferences is that two marine transgressions have occurred, one in Wurm Sub-interglacial and the other Postglacial. The former had caused the study area to be in an estuary-bay envirment over the transgression maximum, with a sea level of no less than 10 m below present; foe latter reached its maximum over the Atlantic stage, with sedimentary environments of estuary-bay, hay or shallow sea, and the sea level arrived at the highest elevation in about 6 - 5 ka B.P. Furthermore, it is notable that, during the Late Wurm Glacial, the study area area had principally been in an estuary-bay environment, although the climate, like many other areas, turned cold and dry, It reflects a general trend of crustal subduction in Jiulong Estudrine Plain over this pened. 展开更多
关键词 environmental change Late PLEISTOCENE jiulong ESTUARINE PLAIN Fujian Province
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Role of mangrove in mercury cycling and removal in the Jiulong Estuary 被引量:3
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作者 Lin Peng and Chen RonghuaBiology Department of Xiamen University, Xiamen, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1990年第4期622-624,共3页
Baseline of mercury in mangrove swamp The mercury content in sediments in the Jiulong Estuary was determined in 1984 and 1985(Table 1). The highest content of mercury in sediments (300×10) was found in Ditou, con... Baseline of mercury in mangrove swamp The mercury content in sediments in the Jiulong Estuary was determined in 1984 and 1985(Table 1). The highest content of mercury in sediments (300×10) was found in Ditou, contrast-ing strongly with the low content of 36×10in Port Dongzhai in the Hainan Island. Tab1e 1 showsthat the average content of mercury in sediments in the Jiulong Estuary is 140×10and the averageof four areas is 72×10. This value means that these areas have not been heavily contaminated by 展开更多
关键词 high Role of mangrove in mercury cycling and removal in the jiulong Estuary
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Size-fractionated uranium isotopes in surface waters in the Jiulong Estuary in China 被引量:1
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作者 LU E ZHANG Lei +5 位作者 CHEN Min QIU Yusheng XING Na YANG Weifeng LI Yanping HUANG Yipu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2008年第1期29-41,共13页
Surface water was collected from the Jiulong Estuary for determination of activity concentrations of uranium isotopes in different size fractions, namely, greater than 53, 10 -53, 2 - 10, 0.4 -2 μm, 10 000 u -0.4 μm... Surface water was collected from the Jiulong Estuary for determination of activity concentrations of uranium isotopes in different size fractions, namely, greater than 53, 10 -53, 2 - 10, 0.4 -2 μm, 10 000 u -0.4 μm and less than 10 000 u fractions by microfihration and cross-flow uhrafiltration technologies. Results indicated that most of the dissolved uranium ( 〈 0.4 μm) exis- ted in the low molecular mass fraction ( 〈 10 000 u), and the colloidal uranium-238 (10 000 u -0.4 μm) only contributed less than 1% of the dissolved uranium-238. The fractions of colloidal uranium in the dissolved phases decreased with the increasing sa- linity. A positive linear relationship between uranium-238 activities and salinities was observed for the dissolved, colloidal and low molecular mass fractions, indicating a conservative behavior of uranium in the Jiulong Estuary. In the particulate phases ( 〉 0.4 μm), the partitioning of uranium isotopes among different size fractions was controlled by the partitioning of particle concentrations. In the regions with salinities below 20, the partitioning of uranium-238 among different size fractions was as follows: 10 - 53 μm 〉 2 - 10 μm 〉 0.4 - 2 μm greater than above 53 μm. However, the order at the offshore station with salinities above 30 changed as follows : 0.4 - 2 μm 〉 10 - 53 μm 〉 2 - 10 μm greater than above 53 μm. The fraction of the 0.4 - 2 μm particles increased at the offshore station, suggesting the increased contribution of the authigenic uranium. The activity ratio of uranium-234 to uranium-238 in the dissolved phases, including the low molecular mass fraction and the colloidal fraction, was larger than unity, showing the occurrence of excess uranium-234. In contrast, the activity ratio of uranium-234 to uranium-238 in all size fractions of the particulate phase was close to the equilibrium value (1.0). The observed different values of the activity ratio of uranium-234 to uranium-238 in the dissolved phase and the particulate phase were ascribed to the preferential leaching of uranium-234 and the small amount of the leaching particulate uranium. The mass ratio of thorium-232 to uranium-238 also showed different values between the dissolved phase and the particulate phase. Mass ratio of thorium-232 to uranium-238 in the dissolved, colloidal and low molecular mass fractions was less than unity, while those in the different size fractions of particulate phases were larger than unity, reflecting a different behavior between uranium and thorium during their transport into the ocean. 展开更多
关键词 uranium isotopes size fractionation jiulong Estuary in China
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Qeochemical behaviour of iodine in Jiulong River Estuary 被引量:1
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作者 Guo Jinbao and Peng Zhen Department of Oceanography, Xiamen University, Xiamen, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1989年第1期91-99,共9页
Dissolved iodine species and the relationship between its distribution and salinity in Jiulong River estuarine water have been determined. It has been found that the total iodine, iodate and iodide are positive linear... Dissolved iodine species and the relationship between its distribution and salinity in Jiulong River estuarine water have been determined. It has been found that the total iodine, iodate and iodide are positive linear with salinity. This indicates that dissolved iodine species (IO-3 and I- ) in estuarine water .how conservative behaviour. The river water contains 2. 40μg/1 as iodide and less than 1. 0μg/1 as iodate, and iodide is the predominant species. Whereas the sea water contains 39. 4μg/1 as iodate and 4. 00μg/1 as iodide, and iodate is the dominant form. The distribution of dissolved iodine in pore water, as a function of depth, has been studied. Iodine in pore water occurs as iodide. The apparent fluxes of soluble iodine from the sediment to the overlying water in the estuary have been determined. The values are 2. 4 (15℃) and 27μmol/(m2·d) (30℃) respectively. 展开更多
关键词 Qeochemical behaviour of iodine in jiulong River Estuary
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Fast acclimation of phytoplankton assemblies to acute salinity stress in the Jiulong River Estuary
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作者 Gang Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第8期78-85,共8页
Mixing of freshwater and seawater creates the well-known salinity gradients along the estuaries. In order to investigate how phytoplankton respond to the acute salinity changes, we exposed natural phytoplankton assemb... Mixing of freshwater and seawater creates the well-known salinity gradients along the estuaries. In order to investigate how phytoplankton respond to the acute salinity changes, we exposed natural phytoplankton assemblies from the Jiulong River Estuary to differential saline field water while continuously monitoring their photosynthetic performances under both indoor-and outdoor-growth conditions. When the natural cell assemblies from salinity 30 field water were exposed to series low saline field water(salinity 25, 17, 13 and 7.5), the effective Photosystem II quantum yield(ΔF/Fm′) decreased sharply, e.g., to one-fifth of its initials after 5 min exposure to salinity 7.5 field water, and then increased fast during the following 40 min and almost completely recovered after 320 min. During such an exposure process, non-photochemical quenching(NPQ) sharply increased from 0 to 0.85 within 5 min, and then decreased to nearly 0 within the following 70 min. When these cells re-acclimated to salinity 7.5 field water were exposed to series high saline field water(salinity 13, 17, 25 and 30), a similar response pattern was observed, with the decreased ΔF/Fm′ accompanied with increased NPQ, and followed by the recovery-induced increase in ΔF/Fm′ and decrease in NPQ. A similar response pattern as ΔF/Fm′to the acute osmotic stress was also observed in the photosynthetic carbon fixation capacity according to radiocarbon(14C) incorporation. Our results indicate that estuarine phytoplankton assemblies could rapidly recover from the acute osmotic stress, implying a potential cause for their frequent blooms in coastal-estuarine waters where despite drastically varying salinity, available nutrients are abundant due to the land-derived runoffs or mixing-caused relaxations from sediments. 展开更多
关键词 PSII quantum yield carbon FIXATION salinity gradients PHYTOPLANKTON ASSEMBLIES jiulong River ESTUARY
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Distribution and number change of the Littorinid (Gastropoda) on intertidal hard bed in the Jiulong Estuary, Fujian Province
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《Acta Oceanologica Sinica》 SCIE CAS CSCD 1990年第2期293-302,共10页
-Among four species of Littorinid, Littorina scabra, L. brevicula, Nodiliitorina millegrana and N. pyramidalis pyramidalis, on the hard intertidal zone in the Jiulong Estuary, Fujian, L. scabra has the most extensive ... -Among four species of Littorinid, Littorina scabra, L. brevicula, Nodiliitorina millegrana and N. pyramidalis pyramidalis, on the hard intertidal zone in the Jiulong Estuary, Fujian, L. scabra has the most extensive distribution both vertically and horizontally, and the highest anual average density. The uppermost limit of vertical distribution of N. pyramidalis pyramidalis is higher than the other three Littorinid. Desiccation is a main factor affecting the uppermost limit of vertical distribution of the Littorinid. The increasing wave action will raise the uppermost limit vertical distribution of Littorinid. With seasonal changes, the densities of the Littorinid also change in different tidal zonations. Difference in salinity is the main factor affecting the horizontal distribution of the Littorinid in the estuary. 展开更多
关键词 Li on intertidal hard bed in the jiulong Estuary Distribution and number change of the Littorinid
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Characteristics of Heavy Minerals Composition and Distribution in Jiulong River Estuary Sediment
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作者 徐茂泉 李超 +1 位作者 许文彬 孙美琴 《Marine Science Bulletin》 CAS 2003年第1期75-87,共13页
The bottom sediment samples were gathered during island investigation in 1994 and in the period of carrying out the natural science fund project of Fujian in 1999. The composition, distribution and assemblage characte... The bottom sediment samples were gathered during island investigation in 1994 and in the period of carrying out the natural science fund project of Fujian in 1999. The composition, distribution and assemblage characteristics of heavy minerals which granularity distributes from 0.063 to 0.125 mm in the sediment from Jiulong River estuary are studied in the paper. The results show that there are 49 kinds of heavy minerals and the average content of them is 9.38 %. The dominant and characteristic minerals are magnetite, hematite, epidote, ilmenite, limonite, hornblende, zircon, andalusite, biotite and so on. 4 mineral assemblage ⅠⅡzones (.The watercourse gateway of Jiulong River mineral zone, . The northern estuary ⅢⅣof Jiulong River mineral zone, . The southern estuary mineral zone, . The eastern estuary of Jiulong River mineral zone ), can be divided based on the heavy mineral contents and the distribution characteristics, which not only relates to the matter sources but also is controlled by hydrodynamic condition and the sedimentary environment in the Jiulong River estuary. 展开更多
关键词 jiulong River estuary heavy mineral distribution characteristics mineral assemblage sedimentary environment
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Distribution and number change of the Littorinidae (Gastropoda) on intertidal hard bed in the Jiulong River Estuary
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作者 Yi Jiansheng and Li FuxueDepartment of Oceanography, Xiamen University, Xiamen, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1989年第1期160-160,共1页
There are 4 species of Littorinidae on the intertidal hard bed in the Jiulong River Estu-ary. They are Littorina scabra, L. brevicula, Nodilittorina pyramidalis pyramidalis and N.millegrana. Of these species, L. scabr... There are 4 species of Littorinidae on the intertidal hard bed in the Jiulong River Estu-ary. They are Littorina scabra, L. brevicula, Nodilittorina pyramidalis pyramidalis and N.millegrana. Of these species, L. scabra is a dominant species. According to the results of in-vestigation, we find distribution patterns of the Littorinidae on intertidal hard bed in theestuary as follows: (1)There is no Littorinid species at Haicheng Station. (2)There is only Lit- 展开更多
关键词 GASTROPODA Distribution and number change of the Littorinidae on intertidal hard bed in the jiulong River Estuary
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Stable isotope geochemical characteristics of dissolved inorganic carbon in the Jiulong River Estuary, Fujian Province, China 被引量:2
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作者 LIU Qiming WU Qiong +2 位作者 CAO Yinglan LIN Jinmei JIAO Yupei 《Chinese Journal Of Geochemistry》 EI CAS CSCD 2014年第2期178-182,共5页
The isotopic composition of dissolved inorganic carbon(DIC) in estuarine environments has been studied for its significant role in determining the isotopic composition of inorganic/organic matter and its applications ... The isotopic composition of dissolved inorganic carbon(DIC) in estuarine environments has been studied for its significant role in determining the isotopic composition of inorganic/organic matter and its applications to the study of various natural processes. In this paper, based on the stable isotope geochemical characteristics of dissolved inorganic carbon in the Jiulong River Estuary, the following conclusions are drawn:(1) δ13CDIC values are mainly controlled by the mixing ratio of fresh water and sea water;(2) δ13Cphytoplankton values are linearly related to the δ13CDIC values;(3) δ13CPOM values for the Jiulong River Estuary are affected by anthropogenic pollution significantly; and(4) the comprehensive analysis of δ13Cphytoplankton, δ13CPOM and δ13CDIC shows that along with increasing salinity, the proportion of POM derived from the degradation of phytoplanktons gradually increases. 展开更多
关键词 同位素地球化学特征 溶解无机碳 九龙江口 稳定 福建省 同位素组成 九龙江河口 中国
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Concentrations and classification of HCHs and DDTs in soil from the lower reaches of the Jiulong River, China
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作者 Jiaquan ZHANG Shihua QI +5 位作者 Xinli XING Lingzhi TAN Wei CHEN Ying HU Dan YANG Chenxi WU 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2012年第2期177-183,共7页
Soil is an important source to other environ- mental media and organisms for organochlorine pesticides (OCPs) bioaccumulation. Twenty-four representative sur- face soil samples were collected from the lower reaches ... Soil is an important source to other environ- mental media and organisms for organochlorine pesticides (OCPs) bioaccumulation. Twenty-four representative sur- face soil samples were collected from the lower reaches of the Jiulong River, China, in 2009. The concentrations of hexachlorocyclohexane isomers (HCHs) ranged from 0.38 to 39.52 ng.g~, with a mean value of 9.51 ng.g-~. The concentrations of dichlorodiphenyltrichloroethanes (DDTs) and their metabolites were within the ranges of 0.94-700.99 ng. gl, with a mean value of 71.17 ng. g-1. The concentrations of HCHs and DDTs in the soil were lower than the first grade level (50 ng. g-a) of the Chinese Environmental Quality Standard (GB 15618-1995). Hier- archical Cluster Analysis (HCA) and Pearson's bivariate Correlations Analysis (PCA) were used to analyse the distribution and contamination levels of OCPs in this region. The results showed that DDTs were the major contaminants and there were no significant correlations between various OCPs concentrations and the total organic carbon (TOC) contents. A significant positive correlation was observed between HCHs and DDTs (p 〈 0.01), which indicates that HCHs and DDTs may have similar sources and fate in the study area. 展开更多
关键词 jiulong River hexachlorocyclohexane (HCH)and dichlorodiphenyltrichloroethan (DDT) classification Hierarchical Cluster Analysis (HCA) Pearson's bivariateCorrelations Analysis (PCA)
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Distribution,fluxes and decadal changes of nutrients in the Jiulong River Estuary,Southwest Taiwan Strait 被引量:18
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作者 YAN XiuLi ZHAI WeiDong +3 位作者 HONG HuaSheng LI Yan GUO WeiDong HUANG Xiao 《Chinese Science Bulletin》 SCIE EI CAS 2012年第18期2307-2318,共12页
The Jiulong River Estuary (JRE) is a typical subtropical macro-tide estuary on the southwest coast of the Taiwan Strait (TWS),which has been greatly impacted by human activities over the past 30 years.To understand nu... The Jiulong River Estuary (JRE) is a typical subtropical macro-tide estuary on the southwest coast of the Taiwan Strait (TWS),which has been greatly impacted by human activities over the past 30 years.To understand nutrient dynamics and fluxes under such a heavy background of anthropogenic perturbation,eight cruises were conducted from April 2008 to April 2011,covering both wet (May to September) and dry (October to April next year) seasons.Nutrient concentrations were very high for the freshwater end-member in the upper reach of the JRE (nitrate (NO 3-N):120-230 mol L-1 ;nitrite (NO 2-N):5-15 mol L-1 ;ammonium (NH 4-N):15-170 mol L-1 ;soluble reactive phosphorus (SRP):1.2-3.5 mol L-1 ;dissolved silicate (DSi):200-340 mol L-1).In dry seasons,concentrations of these nutrients were higher than in wet seasons.Nitrate was the dominant chemical species of dissolved inorganic nitrogen (DIN),with percentages of 67%-96% in wet seasons and 55%-72% in dry seasons.Distributions of NO 3-N and DSi against salinity were nearly constant during all cruises,and showed generally conservative mixing behaviors in the estuary (1<Salinity<32).The concentrations of SRP varied within a narrow range of 1.0-2.0 mol L-1 in low/middle salinity areas,and they were quickly diluted by relatively oligotrophic near-shore seawater in the high salinity region.Based on a temporally high-resolution water discharge dataset,riverine fluxes of DIN,SRP and DSi into the JRE were calculated at 34.3 10 3 t N a 1,0.63 10 3 t P a-1 and 72.7 10 3 t Si a-1,respectively.In comparison,estuarine export fluxes of DIN,SRP and DSi from the JRE to the TWS were estimated at 34.8 10 3 t N a-1,0.82 10 3 t P a-1 and 71.6 10 3 t Si a-1.The estuarine addition flux of SRP was independently estimated at 0.16 10 3 t P a-1.In comparison with major world rivers,the Jiulong River shows a very high areal yield rate of NO 3-N.In comparison with historical datasets from 1980s-1990s,concentrations of NO 3-N and SRP increased 2-3 times in upper/middle areas of the JRE,while DSi remained at the same level.The latter is much different from decadal nutrient changes in the Mississippi River and the Yangtze River/Estuary.Such nutrient changes may fundamentally contribute to recent red tide events in the JRE and adjacent Xiamen Bay. 展开更多
关键词 年代际变化 九龙江口 营养物质 台湾海峡 通量 西南 溶解无机氮 海岸河口
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加强茶文化体系建设提升茶产业发展水平——以松溪县九龙大白茶产业为例
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作者 刘新永 朱步泉 +3 位作者 施成就 林国华 范颖洁 叶昌博 《茶叶》 2024年第2期107-111,共5页
九龙大白茶是源于松溪的优良特色茶树品种,为了进一步促进茶产业转型升级,松溪县把发展九龙大白茶产业作为主要抓手。本文在分析松溪县茶产业和悠久的茶文化历史、文化资源的基础上,针对存在的茶文化营销和茶品牌建设滞后的不足,提出加... 九龙大白茶是源于松溪的优良特色茶树品种,为了进一步促进茶产业转型升级,松溪县把发展九龙大白茶产业作为主要抓手。本文在分析松溪县茶产业和悠久的茶文化历史、文化资源的基础上,针对存在的茶文化营销和茶品牌建设滞后的不足,提出加强松溪县茶文化体系建设的对策建议,包括通过茶科技提升九龙大白茶种植和加工水平,充分利用松溪本地文化资源开展茶旅融合和茶营销,以提升九龙大白茶的品牌影响力,进而提高松溪县茶产业发展水平。 展开更多
关键词 松溪县 九龙大白茶 茶文化 茶科技、茶产业 茶旅融合
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九龙江口表层沉积物碘含量分析
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作者 林建荣 赵诗悦 《福建林业科技》 2024年第1期83-86,110,共5页
于2021年5—6月对九龙江红树林保护区与非红树林保护区进行布点采样,测定其表层沉积物碘含量和有机碳含量。结果表明:13个采样点中,碘含量范围为3.7~24.8 mg·kg^(-1),差值最高可达7倍,平均值为12.3 mg·kg^(-1);有机碳含量范围... 于2021年5—6月对九龙江红树林保护区与非红树林保护区进行布点采样,测定其表层沉积物碘含量和有机碳含量。结果表明:13个采样点中,碘含量范围为3.7~24.8 mg·kg^(-1),差值最高可达7倍,平均值为12.3 mg·kg^(-1);有机碳含量范围为16~45 g·kg^(-1),平均值为30 g·kg^(-1)。不同类型样品碘含量大小依次为:长林龄林下沉积物>河道清淤沉积物>非林下沉积物>短林龄林下沉积物,其中长林龄林下沉积物碘含量范围为15.7~24.8 mg·kg^(-1),平均值为19.2 mg·kg^(-1);短林龄林下沉积物含量为5.5~6.9 mg·kg^(-1),平均值为6.2 mg·kg^(-1);二者相差3倍以上。有机碳含量最高的为长林龄林下沉积物和河道清淤沉积物,平均值均为32 g·kg^(-1);最低值为短林龄沉积物,含量为22 g·kg^(-1)。不同类型沉积物有机碳含量与碘含量基本呈正相关关系,但相关性不显著;同等有机碳含量的样品,长林龄林下沉积物碘含量显著高于其它样品。 展开更多
关键词 河口表层沉积物 碘含量 有机碳 九龙江
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四川九龙古茶树种质资源农艺性状遗传多样性研究 被引量:1
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作者 牛小军 包兴伟 +7 位作者 郑旭霞 秦秀珍 邱金华 王小亚 沈世魁 辛国田 赵芸 黄海涛 《植物遗传资源学报》 CAS CSCD 北大核心 2024年第2期249-258,共10页
为探究甘孜九龙古茶树种质资源的分布区域、形态特征和农艺性状的遗传多样性,通过基本统计分析、变异系数、多样性指数、主成分分析和聚类分析,对67份九龙古茶树种质资源的21个质量性状和12个数量性状进行了遗传多样性分析和评价。结果... 为探究甘孜九龙古茶树种质资源的分布区域、形态特征和农艺性状的遗传多样性,通过基本统计分析、变异系数、多样性指数、主成分分析和聚类分析,对67份九龙古茶树种质资源的21个质量性状和12个数量性状进行了遗传多样性分析和评价。结果表明:九龙古茶树资源农艺性状变异丰富,除树型和树姿外,质量性状的遗传多样性指数范围为0.17~1.27,平均为0.82,其中以花瓣颜色多样性指数最小,果实形状的多样性指数最大;数量性状变异系数范围为1.38%~29.94%,平均为15.27%,以叶面积的变异系数最高,萼片数的变异系数最低。主成分分析显示,前11个主成分累计贡献率在76.49%,其中叶宽、叶长、叶色和花瓣颜色等性状是九龙古茶树种质资源农艺性状表现出差异的主要因素。21个质量性状聚类分析结果显示,在欧式距离为16.9时,可将67份九龙古茶树种质资源划分为4个类群,聚类结果与海拔高度及地理位置无明显相关性。本次调查的古茶树种质资源中有13份种质位于海拔2400 m以上,长势良好,展现出良好的抗寒性和抗旱性。此外,还有2份种质花瓣颜色特异,1份种质籽粒较大且结果率高。研究结果为九龙古茶树种质资源收集、保护和利用奠定一定基础。 展开更多
关键词 九龙 古茶树 农艺性状 多样性分析
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