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241.
分析了沿海滩地3种框围养鱼方式(即精料、种草、化肥养鱼)的能量转换效率及种草养鱼的经济效益。初步得出:在沿海滩地低投入框围养鱼中应重视对太阳能的利用;种草养鱼在3种养鱼方式中能量转换效率最高,经济效益较佳,应推广种草养鱼技术,提高资源利用率。 相似文献
242.
Based on a phenomenology that is rather frequent in the Gulf of Trieste (Northern Adriatic Sea), we analytically model the short time evolution of the temperature field inside a shallow layer of coastal water induced by a sudden offshore wind. In particular, we reproduce in a very simple way the unsteady surfacing of the isotherms forced by the marine current circulating in a vertical plane perpendicular to the coastline. The model is in agreement with the observations of a significant event recorded on 25 June, 2002 in the Gulf of Trieste. 相似文献
243.
通过建筑与水体的相互关系,阐述建筑与自然水环境、人工水环境的有机结合.在水体的形式、形态和造型等方面,详细介绍了水在建筑设计与室内设计中的应用和处理手法. 相似文献
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施加生物炭对河流沿岸土吸附铜的影响机制 总被引:1,自引:0,他引:1
为探究生物炭施加对河流沿岸土吸附铜的影响机制,采集嘉陵江流域(川渝段)内苍溪(CX)、南部(NB)、嘉陵(JL)和合川(HC)沿岸土表层(S,0~20 cm)、亚表层(D,20~40 cm)共8种土样,分别将1%(质量比)生物炭(B)加入到8种土样中形成混合土样(CX_(SB)、NB_(SB)、JL_(SB)和HC_(SB); CX_(DB)、NB_(DB)、JL_(DB)和HC_(DB))。以原始土样作为对照,批处理法研究各供试土样在不同温度、pH和离子强度下的Cu~(2+)吸附和热力学特征,并分析Cu的吸附形态。结果显示:(1)各供试土样对Cu~(2+)的等温吸附都适用Langmuir模型描述,Cu~(2+)的最大吸附量q_m在62. 20~363. 64 mmol/kg之间,S层土样对Cu~(2+)的吸附量均呈现JL NB CXHC的趋势,而D层土样呈现JL CX NB HC的趋势。施加生物炭有助于增强D层土壤对Cu~(2+)的吸附。(2) 20~40℃范围内,各供试土样对Cu~(2+)的吸附量均随温度的升高而升高,表现为增温正效应。热力学参数结果表明各混合土样对Cu~(2+)的吸附是一个自发、吸热和熵增的过程。(3) pH的升高有利于各供试土样对Cu~(2+)的吸附。随着离子强度的增加,各混合土样(HC_S和HC_D除外)对Cu~(2+)的吸附量均呈现先增后降的趋势,0. 1 mol/L时最大。(4)土样中吸附的铜主要以碳酸盐结合态和铁锰氧化物结合态铜存在,生物炭的施加增加了土样中可交换态(HC除外)和有机结合态铜含量,而对碳酸盐结合态和铁锰氧化物结合态铜影响较小。供试土样对Cu~(2+)的q_m主要是由CEC和比表面积决定的。 相似文献
247.
黄河口典型潮沟土壤碳氮分布特征规律 总被引:1,自引:0,他引:1
为探究黄河三角洲盐沼土壤碳氮含量在潮沟水系中的时空分布特征,选取黄河口一条典型的潮沟系统,采集一、二、三级潮沟表层土壤,探寻土壤有机碳、总氮与土壤容重、盐度、pH等理化因子的相关关系。结果表明:土壤有机碳和总氮在时空尺度上表现出极大的异质性特征。时间尺度上,土壤有机碳和总氮出现先上升后下降的趋势。空间尺度上,一级潮沟土壤有机碳和总氮平均值(2.9 g·kg-1、0.36 g·kg-1)大于二级(1.4 g·kg-1、0.18 g·kg-1)、三级(1.6 g·kg-1、0.21 g·kg-1)潮沟。相关分析表明,土壤有机碳和总氮与盐度呈显著正相关(P<0.01),与容重呈显著负相关(P<0.01)。盐沼湿地土壤碳氮含量受土壤水盐条件的影响,而潮沟水系的树状结构对水盐条件的影响是导致土壤碳氮含量时空差异分布的重要因素。 相似文献
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Abstract Total organic carbon, humic substances, and the species of trace metals (including Cu, Zn, Pb, Cd, Cr, Mn and Fe) in six and seven phases, such as bioexchangeable (P1), skeletal (carbonates, P2), easily reducible (Fe and Mn oxides, P3), moderately reducible (crystalline Mn oxides, P4), organic matters with sulphides (P5), and detritus with minerals (P6) as well as organic with humic substances (PB4) and organic residues (PB6), were analyzed in sediments from the Taiwan Erhjin coastal (including river and estuarine) area, where places we found the copper pollution. Results indicate that higher percentages of P1 and P2 for copper, zinc, lead, cadmium and manganese in samples collected in March and September of 1990 were much higher than those in P3-P6. High percentages of chromium and iron in samples respectively collected in March and September of 1990 were found in P6. for the seven phase analysis, higher percentages of copper species in PB4 and PB6 as well as iron species in PB7 were observed. On the other hand, purified humic acid with the high contents of manganese and iron in humic acid as well as purified fulvic acids were generally found at the upstream stations; and low values at coastal stations. However, extremely high copper (as high as 1750μg g?1, dry weight in fulvic acid and 820μg g?1 in humic acid) and lead (821μg g?1 in humic acid) concentrations with relatively high manganese and iron concentrations were observed in humic substances from the station near the copper recycling area. Comparing the results obtained from the Antarctic Ocean sediments with those from the Taiwan Erhjin Chi coastal sediments, the human impacts on the latter are evaluated. 相似文献
250.
J. C. Chuang Y. C. Lan Y. S. Hsu S. L. Chuang S. R. Liaw C. S. Chang 《Chemistry and Ecology》2013,29(1-2):97-104
Abstract This study introduces the principles of KMG's (Kaoshiung Municipal Government) dealing with the non-poisonous urban and industrial waste through reclamation of shore land in reinforcing a sense of coastal protection and land development in Tai-Lin-Pu coastal area, southern Taiwan. Through a series of experimental studies, we found that substitutes of coarse aggregate with a broad spectrum of integrating slag powder, fly ash, and cementitious material can be obtained with a benefit up to 80% saving of cement. the integrated aggregates from the non-poisonous industrial wastes were subsequently made into armour units and used in the field tests at Tai-Lin-Pu coastal area, where the shorelines are seriously eroded. After being subjected to several severe typhoon advents, the results showed that the waste-made units used as the protection breakwater, together with construction wastes and excavated soil as the filling material, prove to be an effective practice in utilizing recycled urban waste to reclaim erosive shore lands. Moreover, this study also demonstrates that through detailed analysis of the waste characteristics, scrap material could be turned into valuable construction aggregates, and highlights the value of non-poisonous urban and industrial waste as a alternative resource for the shore protection engineering. 相似文献