Water Flow, Trophic Depletion, and Benthic Macrofauna Impoverishment in a Submarine Cave from the Western Mediterranean   总被引：1，自引：0，他引：1  

Mikel Zabala  Tecla Riera  Josep Maria Gili  Manel Barange  Agustin Lobo  Josep Peñuelas 《Marine Ecology》1989,10(3):271-287

Abstract. Biotic zonation and severe impoverishment of benthic macrofauna are two of the most conspicuous features of submarine caves. The prevailing explanation assumes trophic depletion caused by reduction of water flow. However, no isolation of water was found in the studied Catalan submarine cave, even in the wall microlayer. Fluorescein diffusion was so fast that it was detectable everywhere in the cave already only a few minutes after the injection. The rate of dissolution of plaster spheres was even greater in the cave than in a nearby tunnel – without benthic macrofauna impoverishment – showing a considerable water flow. The oxygen concentration of water in dialysis bags placed at varying distances from the cave walls showed that no wall microlayer gradients were present.
Biochemical gradients did not indicate any decrease in food supply. Although photosynthetic pigment concentration generally decreased inside the cave, and although the gradients were not linear but formed different patterns throughout the cave, the BOD₅, the POM, the C:N ratio, the [³H]-thymidine incorporation rate, and the ETS activity were higher in the inner part of the cave. There was an accumulation of detritic material and bacteria in the inner parts that constitute a plausible food supply for benthic macrofauna.
If neither water motion nor food supply can be invoked, research into the causes of zonation and disappearence of benthic macrofauna is proposed to be carried out on biotic interactions and behavioural processes.  相似文献   

Field studies of the flow structure in a straight reach of the conwy estuary     

I. Guymer  J. R. West 《Estuarine, Coastal and Shelf Science》1991,32(6)

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光生态膜对水稻秧苗生态的影响   总被引：1，自引：0，他引：1  

孟继武  郑荣儿  李茂生  葛景强  王士勇  曹柏青  李威 《中国海洋大学学报(自然科学版)》2003,33(2):312-316

采用浮染法将荧光助剂、红外辐射剂、着色剂分散进低密度聚乙烯 (LDPE)树脂中 ,通过挤出吹塑制成厚 0 .1 2 mm,宽 1 2 m的无滴、长寿棚膜。光生态膜将 550 nm的绿光变换为红光提高了红光成分 ,有效的调整了辐射进入棚内的太阳光谱 ,补充了红光的辐射强度 ,改善了农作物的光生态环境 ,促进了作物的光合作用。用这种光生态膜苫盖温室进行水稻育秧 ,在哈尔滨市 1 2个县进行大面积试验示范 ,提高了作物的产量 ,使水稻产量提高了 8.6%。  相似文献   

Prediction method of sand-movement direction in rivers by geochemical elements     

K. Mizumura  T. Nishimoto  Y. Kumagai  T. Yamamoto 《Environmental Geology》1996,28(2):88-98

 The analysis of sand samples by X-ray fluorescent spectroscopy (XRF) gives the ratio of the geochemical elements to construct the sand samples. The application of the ratio matching to sand samples represents the correlation number between two sand samples with respect to geochemical elements. When the correlation number between two sand samples is low, the two samples are not geochemically similar each other. This denotes that the exchange of sand between two sampling points is scarce or the two samples are independent. When the correlation number between two sand samples is high, the two samples are geochemically similar, signifying that the exchange of sand between two sampling points is frequent or there is sand movement between two sampling points. If there exists prominent sand movement in the study area, the correlation number is almost 1 and kilo count number per second of each geochemical element per weight decreases along the flow direction. The decrease is caused by the reduction of sizes and the adherence of dirt on the surface of sand particles. Since the flow direction in rivers is usually the same as the direction of sand movement, it can be verified. This study obtains satisfactory results applying the method of prediction in sand movement to sediments in rivers. Received: 17 May 1995 · Accepted: 14 August 1995  相似文献   

X射线荧光光谱测定荧光粉中硅铁锌钴   总被引：1，自引：0，他引：1  

徐海  李宝军 《岩矿测试》2004,23(4):317-318

采用溶液法配制标准,粉末直接制备样饼,用SRS300型X射线荧光光谱仪测定彩色荧光粉中的SiO2、Fe2O3、Co、Zn组分含量,取得较满意的结果,与已知含量样品比较,所测组分的结果基本相符。精密度检验SiO2、Fe2O3、Co、Zn的RSD均<3%(n=10)。  相似文献   

西南岩溶石山地区岩溶地下水示踪试验与分析——以湖南湘西大龙洞为例   总被引：4，自引：0，他引：4  

邓振平  周小红  何师意  罗英 《中国岩溶》2007,26(2):163-169

围绕大龙洞水库成库条件调查中存在的疑点问题开展示踪工作。根据示踪试验区的水文地质条件,选择降雨时地表水向地下集中渗漏排泄的狗肉寨极乐村洼地落水洞作为投放点,并在极乐村洼地落水洞的北东大龙洞地下河出口附近的鬼冲地下河、鬼冲泉和大龙洞地下河出口下方对岸100m处的Y034季节性水点(表层带岩溶泉点)及大龙洞地下河出口设置接收点,采用弱酸性红A荧光染料类试剂作示踪材料。示踪结果显示,鬼冲地下河、鬼冲泉和大龙洞地下河与投放点的连通性差;季节性水点Y034与投放点的连通性好;表明通过狗肉寨极乐村洼地落水洞汇集转化成的岩溶地下水与表层岩溶带季节性岩溶泉水水力联系密切,而与鬼冲地下河、大龙洞地下河之间则存在有地下分水岭。   相似文献   

Will harmful dinoflagellate Karenia mikimotoi grow phagotrophically?     

���崺  ���ʳ�  �ξ���  ����  ���Ʒ�  ������ 《中国海洋湖沼学报》2011,29(4):849-859

We studied the phagotrophic ability of dinoflagellate strain Karenia mikimotoi KM-Lü (isolated from the South China Sea), using fluorescent microspheres, bacteria isolated from the culture of K. mikimotoi and a marine microalgae Isochrysis galbana. We found that K. mikimotoi cultured under conditions of high light intensity could ingest fluorescent microspheres (diameters 0.5 and 2.0 μm) and fluorescence-labeled bacteria and microalgae. Under a low light intensity, however, only fluorescent microspheres (diameter 0.5 μm) and fluorescence-labeled microalgae were ingested. K. mikimotoi showed better growth by ingesting living marine bacteria or microalgae I. galbana than the controls, either in nutrient-depleted or nutrient-replete conditions. In nutrient-depleted conditions, the growth of K. mikimotoi was more significant with I. galbana as the prey item. In conclusion, the harmful dinoflagellate K. mikimotoi from the South China Sea has apparent phagotrophic ability, and some marine bacteria and microalgae may promote the growth of K. mikimotoi.  相似文献   

贝类精子质量检测与评价方法的研究Ⅴ:栉江珧精子线粒体活性的荧光检测     

郑娇  王梅芳  余祥勇 《广东海洋大学学报》2011,(6):86-90

采用罗丹明123(Rh123)和碘化丙啶(PI)两种荧光染料对栉江珧(Atrina pectinata)精子线粒体活性进行检测,比较不同染液浓度和染色时间的检测效果,并用该方法检测和比较超低温冷冻保存对线粒体活性的影响。结果显示:Rh123和PI染色的最适染液浓度均为10μg/mL,染色时间控制在10 min之内;染色后具有线粒体活性的精子发出绿色荧光,死精子发出红色荧光,质膜受损但线粒体还未受损的精子发出红绿色荧光,表明Rh123和PI双荧光染色检测栉江珧精子线粒体活性是可行的;精液经冷冻后,线粒体活性为61.9%、质膜完整率56.8%,显著低于新鲜精液组(95.3%、93.5%),表明冷冻对精子结构会造成不同程度的损伤,Rh123和PI双荧光染色法可用来检测栉江珧精子质量。  相似文献   

应用荧光显微技术判别吐哈盆地储层含油水性   总被引：2，自引：0，他引：2  

张小青  伊海生  危国亮  万永清  黄天雪 《地球科学与环境学报》2005,27(2):56-59

通过在荧光镜下的油水特征实验，分别得出油、油包水、水包油、含油水、水的荧光特征，然后对吐哈盆地单井储层的油层、水层荧光特征反复实验，并与试油结果对比，归纳总结出了油层、水层及油水界面的识别标志。油层特征主要为荧光发光较好且均匀、大面积油包水；水层特征主要为荧光发光不均匀，可动水普遍，并出现水包油现象；油水界面特征主要为荧光从均匀发光过渡到不均匀发光，孔隙由可动油充填过渡到由可动水充填。提出了吐哈盆地储层含油规律性，从而为探井试油、油层划分提供了准确可靠的依据。  相似文献   

南极乔治王岛六种苔藓植物的X荧光分析   总被引：5，自引：4，他引：5       下载免费PDF全文

黄宇营  巨新  康士秀  吴自勤  沈显生  孙立广  尹雪斌  张莉 《极地研究》2001,13(1):50-56

在无标样条件下 ,我们利用微束 X荧光分析法对南极乔治王岛的 6种苔藓植物的叶和茎进行重元素分析。它们是 :Andreaea regularis,Bryum muehlenbeckii,Drepanocladus uncinatus,Brachythecium subpilosum,Tortula saxiola,Ditrichum austro- georgicum。研究结果发现 ,不同苔藓植物对各种不同重元素的吸收能力不同 ,即使是同一种植物 ,叶和茎中的重元素成分也有差异。在 6种苔藓中 ,Andreaea regularis体内的重元素种类最少 ,但其对 Fe有较强的吸收。由于南极环境条件优越 ,在苔藓植物体内 ,尚未发现大量有毒重金属元素的存在  相似文献