甘肃阳山金矿床不良工程地质因素分析与防治     

徐恒军  李石桥 《四川地质学报》2006,26(3):147-149

对矿区不良工程地质因素进行分析,确定了矿区工程地质条件;基本阐明了对不良工程地质因素危害的防治措施及技术,为下一步矿山开发提供了参考。  相似文献   

矿物材料应用于香烟过滤嘴降害的研究现状与展望     

吴敏  李胜荣 《岩石矿物学杂志》2007,26(2):171-176

总结了近几十年来包括活性炭、沸石、蒙脱石、海泡石、麦饭石、凹凸棒石、氧化铝、氢氧化钠、明矾、纳米材料等矿物材料作为卷烟滤嘴添加剂以去除烟气中有毒有害物质的研究和实验应用及效果。实验结果和市场调查表明,活性炭是减少卷烟危害最快、香烟市场应用增长最快的过滤嘴添加剂。从降低卷烟有害成分的比例和成本等综合因素来看,铝硅酸盐类滤嘴和多材料复合滤嘴亦有很好的应用前景和市场需求,应积极进行研制。  相似文献   

春季水华对南黄海总溶解态无机砷生物地球化学行为的影响   总被引：1，自引：0，他引：1  

孙友旭  任景玲  刘素美  刘诚刚 《海洋学报》2015,37(4):16-27

利用氢化物发生-原子荧光光谱法(HG-AFS)对2007年3月30日至4月23日南黄海海域总溶解态无机砷(TDIAs,[TDIAs]=[As5+]+[As3+])的含量进行了测定,其中针对水华中心区域(BM1站)进行了25h的连续观测,以探讨春季水华对有毒类金属元素砷的生物地球化学行为的影响。结果表明,TDIAs的浓度范围为7.9~22.3nmol/L,平均值为(17.8±1.9)nmol/L。TDIAs在南黄海的分布主要表现为由近岸向外海逐渐升高的趋势,最大值出现在南部海域底层海水中。近岸海域表、底层TDIAs的含量相当,而中、南部海域由于存在明显的密度跃层,表、底层TDIAs的浓度具有显著性差异。2007年3月31日至4月1日研究区域西南部受到沙尘天气和降雨的影响,表层海水中TDIAs的含量显著升高。研究区域中、南部海域在观测期间暴发了典型的黄海春季水华,通过大面观测和对重点区域的连续观测可以发现,水华期间TDIAs的分布和磷酸盐类似,与Chl a呈现出较好的负相关关系(r=0.51,P0.05,n=39)。经初步计算,浮游植物水华对10m以上表层水体中TDIAs的清除量约为2.4nmol/L,占表层保有量的15%左右。通过箱式模型计算得出黄海TDIAs的停留时间约为(18.2±8.5)a,远远低于大洋。通过对该海域砷、磷摩尔比值的计算可以发现,南黄海砷、磷摩尔比值约为大洋中的20倍左右,这可能会引起浮游生物对砷酸盐的大量吸收和转化,从而带来潜在的生态危机,需要引起足够的重视。  相似文献   

河北省近海有害藻华灾害分级、时空分布和优势藻华生物变化特征     

安鑫龙  李雪梅  李志霞 《海洋技术学报》2015,34(1):69-75

为研究1989—2013年河北省近海有害藻华灾害分级、时空分布和优势肇事生物变化特征,对河北省近海累计58次有害藻华记录的发生时间、位置与范围、面积和优势有害藻华生物种类进行了统计分析。结果表明:小型(面积0~100 km2)、中型(100~1 000 km2)、大型(≥1 000 km2)和面积不详的有害藻华中,小型藻华为多发性藻华,发生次数占全省海域累计发生次数的60.35%;5-8月份是藻华多发期,发生次数占累计发生次数的86.21%;2000年后藻华发生频率大增,由原来年均发生1次演变为年均发生4次;秦皇岛海域发生藻华次数最多,占全省海域累计发生次数的57.14%,沧州海域次之,唐山海域最少;秦皇岛海域发生藻华累计面积最大,占全省海域累计发生面积的64.25%,沧州海域次之,唐山海域最小。河北省优势海洋有害藻华生物共计15种,易发性藻华生物夜光藻Noctiluca scintillans引发藻华次数最多,占全省海域累计发生次数的44.83%,2009年前是河北省近海最主要的藻华肇事生物;高发性藻华生物抑食金球藻Aureococcus anophagefferens引发有害藻华累计面积最大,占全省海域累计发生面积的55.57%,2009年后该藻和夜光藻共同成为河北省近海优势藻华肇事生物。  相似文献   

Optical detection of Prorocentrum donghaiense blooms based on multispectral reflectance     

TAO Bangyi  PAN Delu  MAO Zhihu  SHEN Yuzhang  ZHU Qiankun  CHEN Jianyu 《海洋学报(英文版)》2013,32(10):48-56

Prorocentrum donghaiense is one of the most common red tide causative dinoflagellates in the Changjiang （Yangtze） River Estuary and the adjacent area of the East China Sea. It causes large-scale blooms in late spring and early summer that lead to widespread ecologic and economic damage. A means for distinguish- ing dinoflagellate blooms from diatom （Skeletonema costatum） blooms is desired. On the basis of measure- ments of remote sensing refectance [Rrs（λ）] and inherent optical parameters, the potential of using a mul- tispectral approach is assessed for discriminating the algal blooms due to P. donghaiense from those due to S. costatum. The behavior of two reflectance ratios [R1 = Rrs（560）/Rrs（532） and Re = Rrs（708）/Rrs（665）], suggests that differentiation of P. donghaiense blooms from diatom bloom types is possible from the current band setup of ocean color sensors. It is found that there are two reflectance ratio regimes that indicate a bloom is dominated by P. donghaiense; （1） R1 〉 1.55 and R2 〈 1.0 or （2） R1 〉 1.75 and R2 ≥ 1.0. Various sensitivity analyses are conducted to investigate the effects of the variation in varying levels of chlorophyll concentration and colored dissolved organic matter （CDOM） as well as changes in the backscattering ratio （bbp/bp） on the efficacy of this muitispectral approach. Results indicate that the intensity and inherent op- tical properties of the algal species explain much of the behavior of the two ratios. Although backscattering influences the amplitude of Rrs（λ）, especially in the 530 and 560 nm bands, the discrimination between P. donghaiense and diatoms is not significantly affected by the variation of bbp/bp. Since aCDOM （440） in coastal areas of the ECS is typically lower than 1.0 m-1 in most situations, the presence of CDOM does not interfere with this discrimination, even as SCDOM varies from 0.01 to 0.026 nm-1. Despite all of these effects, the dis- crimination of P. donghaiense blooms from diatom blooms based on multispectral measurements of Rrs（λ） is feasible.  相似文献   

The influence of air–sea–ice interactions on an anomalous phytoplankton bloom in the Indian Ocean sector of the Antarctic Zone of the Southern Ocean during the austral summer, 2011     

《Polar Science》2014,8(4):370-384

An anomalous phytoplankton bloom was recorded in the Indian Ocean sector of the Antarctic Zone (AZ) of the Southern Ocean (SO) during the austral summer, 2011. Possible mechanisms for the triggering of such a large bloom were analyzed with the help of in situ and satellite data. The bloom, which formed in January 2011, intensified during February and weakened by March. High surface chlorophyll (Chl) concentrations (0.76 mg m⁻³) were observed in the area of the bloom (60°S, 47°E) with a Deep Chlorophyll Maximum (DCM) of 1.15 mg m⁻³ at a depth of 40–60 m. During 2011, both the concentration and spatial extent of sea ice were high on the western side of the bloom, between 0°E and 40°E, and enhanced freshwater influx was observed in the study area as a result of melting ice. A positive Southern Annular Mode (SAM) (with a resultant northward horizontal advection) and an intense La Niña during 2010–2011 are possible reasons for the high sea-ice concentrations. The enhanced Chl a observed in the study region, which can be attributed to the phytoplankton bloom, likely resulted from the influx of nutrient-laden freshwater derived from melting sea ice.  相似文献   

Estimating the Budgets of Nutrients for Phytoplankton Bloom in the Central Yellow Sea Using a Modified Lower Tropic Ecosystem ModelDOI 10.1007/s11802-014-1900-6     

YUAN Chengyi  WANG Yuheng  WEI Hao 《中国海洋大学学报(英文版)》2014,(1)

A modified lower trophic ecosystem model(NEMURO) is coupled with a three-dimensional hydrodynamic model for an application in the central Yellow Sea. The model is used to simulate the horizontal distributions and annual cycles of chlorophyll-a and nutrients with results consistent with historical observations. Generally, during the winter background and spring bloom periods, the exchange with neighboring waters constitutes the primary sources of nutrients. Howerver, during the winter background period, the input of silicate from the layer deeper than 50 m is the most important source that contributes up to 60% to the total sources. During the spring bloom period, the transport across the thermocline makes significant contribution to the input of phosphate and silicate. During the post spring bloom period, the relative contribution of relevant processes varies for different nutrients. For ammonium, atmospheric deposition, excretion of zooplankton and decomposition of particulate and dissolved nitrogen make similar contributions. For phosphate and silicate, the dominant input is the transport across the thermocline, accounting for 62% and 68% of the total sources, respectively. The N/P ratio averaged annually and over the whole southern Yellow Sea is up to 51.8, indicating the potential of P limitation in this region. The important influence of large scale sea water circulation is revealed by both the estimated fluxes and the corresponding N/P ratio of nutrients across a section linking the northeastern bank of the Changjiang River and Cheju Island. During the winter background period, the input of nitrate, ammonium, phosphate and silicate by the Yellow Sea Warm Current is estimated to be 4.6×1010, 2.3×1010, 2.0×109 and 1.2×1010 mol, respectively.  相似文献   

2010—2011年东海藻华高发区水体层化对东海原甲藻(Prorocentrum donghaiense Lu)藻华的影响   总被引：1，自引：0，他引：1  

戴鑫烽  陆斗定  夏平  王红霞  何飘霞  李冬融 《海洋与湖沼》2014,45(2):217-224

本文通过2010年和2011年不同时空角度对东海原甲藻藻华进行调查,研究水体层化对藻华发生和发展的影响。结果显示,起初东海原甲藻在50m等深线附近的外海繁殖与聚集,然后随着台湾暖流与长江冲淡水的相互作用,东海区域水体层化现象加剧,其细胞丰度越来越大,直至藻华发生并持续推进到近岸。大部分东海原甲藻细胞位于层化水体上方,而且当水体层化现象明显时,藻华的发展最为迅速且呈大规模爆发状态。结果还显示当出现叶绿素高值层时,总是伴随出现温盐突变现象。本项研究不仅第一次从时间角度记录了东海原甲藻藻华的发展动态,而且还发现了东海水体层化现象为东海原甲藻藻华的发生和发展提供了多种环境因子条件,这为该藻华的监控和预测提供了重要的科学依据。  相似文献   

海洋寄生性甲藻——阿米巴藻Amoebophrya spp.的研究进展     

李才文 《海洋学报》2014,36(6):1-9

寄生性甲藻阿米巴藻Amoebophrya是一类广泛寄生于纤毛虫类、放射虫类、甲藻类等海水浮游生物的原生生物,在北大西洋、北太平洋和地中海等营养盐丰富、宿主密度较高的河口和近海水环境中普遍存在,是海洋浮游食物网的重要组成部分。这类寄生性甲藻能够特异性感染海洋浮游甲藻,在有害藻华(harmful algal bloom,HAB)的发生过程中起下行控制作用,将逃脱了浮游动物摄食的浮游植物补充到微食物环(microbial loop)中去。Amoebophrya在近海海洋生态系统中的独特作用日益受到国际上越来越多研究者的关注和重视,并逐渐成为国际上海洋微型生物研究的新热点之一。近年来,已有初步调查研究表明这类寄生性甲藻在我国近海海域广泛存在;然而,目前我国尚缺乏该类寄生性甲藻的相关研究。本文系统综述了国际上该类寄生性甲藻的研究进展,针对目前研究中存在的问题并结合我国有害藻华发生机制相关研究的现状做出了分析和展望,以期推动我国该类寄生性甲藻的相关研究,为进一步阐释寄生性甲藻等海洋微型生物在有害藻华消长过程和海洋微食物环中的作用奠定基础。  相似文献   

The distribution of chlorophyll a and its influencing factors in different regions of the Bering Sea     

KANG Jianhu  CHEN Xingqun  ZHANG Ming 《海洋学报(英文版)》2014,33(6):112-119

The distribution of chlorophyll a(Chl a) and its relationships with physical and chemical parameters in different regions of the Bering Sea were discussed in July 2010. The results showed the seawater column Chl a concentrations were 13.41–553.89 mg/m2 and the average value was 118.15 mg/m2 in the study areas. The horizontal distribution of Chl a varied remarkably from basin to shelf in the Bering Sea. The regional order of Chl a concentrations from low to high was basin, slope, outer shelf, inner shelf, and middle shelf. The vertical distribution of Chl a was grouped mainly from single-peak type in basin, slope, outer shelf, and middle shelf, where the deep Chl a maxima(DCM) layer was observed at 25–50 m, 30–35 m, 36–44 m, and 37–47 m, respectively. The vertical distribution of Chl a mainly had three basic patterns: standard single-peak type, surface maximum type, and bottom maximum type in the inner shelf. The analysis also showed that the transportation of ocean currents may control the distribution of Chl a, and the effects were not simple in the basin of the Bering Sea. There was a positive correlation between Chl a and temperature, but no significant correlation between Chl a and nutrients. The Bering Sea slope was an area deeply influenced by slope current. Silicate was the factor that controlled the distribution of Chl a within parts of the water in the slope. Light intensity was an important environmental factor in controlling seawater column Chl a in the shelf, where Chl a was limited by nitrate rather than phosphate within the upper water. Meanwhile, there was a positive relationship between Chl a and salinity. Algal blooms broke out at Sta. B6 of the southwestern St. Lawrence Island and Stas F6 and F11 in the middle of the Bering Strait.  相似文献