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排序方式: 共有120条查询结果,搜索用时 62 毫秒
51.
James K. H. Fang Christine H. L. Schönberg David I. Kline Ove Hoegh‐Guldberg Sophie Dove 《Marine Ecology》2013,34(2):193-206
This study applied the loss after combustion (LAC) method and the acid decalcification (ADC) method to quantify different components of an excavating sponge. Samples of dried coral skeleton of Favia sp. invaded by the Indo‐Pacific excavating sponge Cliona orientalis Thiele, 1900 were used. The sponge tissue penetrated the 12‐mm‐thick samples to approximately 10 mm. The average proportional weight of organic matter, siliceous spicules, calcareous substrate and salts in the entire samples was found to be respectively 2.5%, 4.4%, 90.5% and 2.5% of dry weight applying the LAC method, and 2.9%, 5.9%, 89.0% and 2.3% of dry weight applying the ADC method. Respective volumetric proportions of the organic matter, spicules, substrate and salts were then calculated to be 6.4%, 5.5%, 85.2% and 3.0% of volume with the LAC method, and 7.4%, 7.2%, 82.7% and 2.7% of volume with the ADC method. The LAC method showed low variability of data and is simple and fast and therefore is recommended. The ADC method generated very similar results to the LAC method. However, due to the handling involved in the ADC method, more than half of the spicules may be lost and the method is therefore not recommended unless careful data corrections are considered. In addition, the buoyant weight method was used to quantify actual substrate weight in the fresh sponge‐substrate samples. This method was found to be at least 97% effective, revealing that buoyant weights can potentially be used to quantify bioerosion rates of excavating sponges. To our knowledge, this is the first study to systemically quantify organic and inorganic components of an excavating sponge and its calcareous substrate, providing improved standard methods for future studies. 相似文献
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Srinivasa Reddy M Basha S Sravan Kumar VG Joshi HV Ghosh PK 《Marine pollution bulletin》2003,46(12):1609-1614
Alang–Sosiya located on the Western Coast of Gulf of Cambay, is the largest ship recycling yard in the world. Every year on average 365 ships having a mean weight (2.10 × 106 ± 7.82 × 105 LDT) are scrapped. This industry generates a huge quantity of solid waste in the form of broken wood, rubber, insulation materials, paper, metals, glass and ceramics, plastics, leather, textiles, food waste, chemicals, paints, thermocol, sponge, ash, oil mixed sponges, miscellaneous combustible and non-combustible. The quantity and composition of solid waste was collected for a period of three months and the average values are presented in this work. Sosiya had the most waste 15.63 kg/m2 compared to Alang 10.19 kg/m2. The combustible solid waste quantity was around 83.0% of the total solid waste available at the yard, which represents an average weight of 9.807 kg/m2; whereas, non-combustible waste is 1.933 kg/m2. There is not much difference between the average of total solid waste calculated from the sampling data (96.71 MT/day) and the data provided by the port authorities (96.8 MT/day). 相似文献
54.
内蒙古满都拉二叠纪海绵生物丘的发现及意义 总被引:6,自引:1,他引:6
在内蒙古自治区达尔罕茂明安联合旗北部满都拉地区进行 1/5万区域地质调查过程中 ,首次于阳新统哲斯组中识别出小型海绵生物丘。海绵生物丘发育于华北板块北部活动边缘晚华力西褶皱造山带上 ,分布于近东西向延伸的大石寨组火山岛弧的两侧 ,南侧在包特格、满都拉苏木等地以小型海绵丘为特征 (局限弧后盆地边缘海绵丘 ) ;北侧发育了规模较大的哲斯敖包生物礁 (开阔台地边缘礁 )。通过对海绵及其他生物化石的古生态分析 ,结合沉积特征探讨了该区阳新世的古地理环境 相似文献
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两种黄海潮间带海绵的元素与氨基酸成分分析 总被引:1,自引:1,他引:0
应用能量色散X射线荧光光谱(EDXRF)分析了黄海潮间带繁茂膜海绵(Hymeniacidon perleve)和肾指海绵(Reniochalina sp.)的无机元素,其中硅是两种海绵中最多的无机元素。繁茂膜海绵较肾指海绵的锌含量高,参照文献数据推测这可能是该属海绵的特性。测定了2种海绵的含水量,有机碳、氮、氢元素和氯基酸在海绵干质量中的比例。分析了繁茂膜海绵在2002年8月到11月中主要无机元素的变化,发现繁茂膜海绵中的硅含量在降低。繁茂膜海绵的氨基酸总量远高于肾指海绵,2种海绵中含量较高的氨基酸是甘氨酸、谷氨酸、天冬氨酸、亮氨酸、缬氨酸、赖氨酸等。元素与氨基酸分析将对海绵细胞培养基开发有帮助。 相似文献
57.
地理国情普查成果的开发应用是地理信息社会化服务的热点领域。本研究从海绵城市建设的角度出发,应用地理国情普查成果,构建一套完整的海绵城市空间布局优化技术。研究结果表明:利用地理国情普查成果优化后的海绵城市空间布局,能有效缓解城市暴雨内涝灾害,对于常年遭遇中等强度降雨的城市效果明显。本文拓展地理国情普查成果应用,进一步提高地理国情成果对政府的辅助决策价值。 相似文献
58.
Tracey E. M. Bates 《新西兰海洋与淡水研究杂志》2018,52(2):247-263
There are still major gaps in our understanding of the impact of ocean acidification (OA) on some groups of organisms within different geographic regions. We investigated the effect of OA on two common and ecologically important temperate sponge species in New Zealand (Tethya bergquistae and Crella incrustans). Sponges were kept at pH 8 (control) and 7.6 for 4 weeks. Responses of the two species varied, with T. bergquistae kept at pH 7.6 showing some mortality in response to reduced pH and evidence of tissues necrosis. In contrast, only one C. incrustans died in the pH 7.6 treatment and showed little evidence of any tissue degradation. Only T. bergquistae showed evidence for physiological effects of reduced pH as respiration rates were generally higher in the pH 7.6 treatment. Our results provide preliminary evidence to support a general tolerance of temperate sponges to reduced pH, but that some species-specific responses may exist. 相似文献
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60.
M. I. Pishkalo 《Astronomische Nachrichten》1994,315(5):391-397
Hα profiles of chromospheric spicules computed for a variety of rotational behavior are compared with an observed profile, which was derived by averaging 11 Hα profiles taken near times of maximum spicule intensity. If turbulent velocity is small or equals zero, calculated profiles are in good agreement with the observed one under the conditions that rotation is non-rigid (faster rotation further away from the axis of the spicule) and the source function decreases in the direction from the spicule axis to the periphery. The comparison of calculated and observed tilts of spicule spectra relative to the direction of dispersion seems to corraborate the non-rigid character of spicular rotation. 相似文献