Studies on intercropping ofPorphyra haitanensis T. J. Chang et B. F. Zheng with Bay ScallopArgopecten irradians Lamarck     

Zheng Baofu  Li Shiying  Guan Mingjin 《中国海洋湖沼学报》1993,11(1):16-20

Results of the experiment of northward transplantation ofPorphyra haitanensis showed that intercrop ofP. haitanensis with Bay Scallop is feasible because the growth duration of both of them is about the same in August–December. Full use of cultivating area, lowering its cost and increasing its product per unit area as well as improving the ecological environment are realized during intercrop. Contribution No. 2152 from the Institute of Oceanology, Academia Sinica.  相似文献   

Trial of a tractor dredger for cockles in Burry Inlet, South Wales     

Cotter  A. J. R.; Walker  P.; Coates  P.; Cook  W.; Dare  P. J. 《ICES Journal of Marine Science》1997,54(1):72-83

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日照港煤码头浚深工程回淤分析   总被引：3，自引：0，他引：3  

于风香  李瑞杰 《海洋湖沼通报》2004,(1):1-7

采用水动力学三维数学模型对日照港煤码头水域的水动力因素进行了计算,并在此基础上对煤码头浚深工程实施后港池和航道回淤进行了计算分析.计算结果与实测结果比较表明:文中模型较好地重演日照港煤码头水域潮流场,对于港池与航道的回淤分析合理可靠.  相似文献   

Recovery of the seabed following marine aggregate dredging on the Hastings Shingle Bank off the southeast coast of England     

Keith Cooper  Sian Boyd  Jacqueline Eggleton  David Limpenny  Hubert Rees  Koen Vanstaen 《Estuarine, Coastal and Shelf Science》2007,75(4):547-558

The aim of this study was to investigate the effect of dredging intensity on the physical and biological recovery times of the seabed following marine aggregate dredging. Two areas of seabed, previously subject to, respectively, relatively high and lower levels of dredging intensity, were identified on the Hastings Shingle Bank. Two reference areas were also selected for comparative purposes. All four sites were monitored annually over the period 2001–2004, using a combination of acoustic, video and grab sampling techniques. Since the site was last dredged in 1996, this was intended to provide a sequence of data 5–8 years after cessation of dredging. However, an unexpected resumption of dredging within the high intensity site, during 2002 and 2003, allowed an additional assessment of the immediate effects and aftermath of renewed dredging at the seabed. The early stages of recovery could then be assessed after dredging ceased in 2003. Results from both dredged sites provide a useful insight into the early and latter stages of physical and biological recovery. A comparison of recent and historic dredge track features provided evidence of track erosion. However, tracks were still visible 8 years after the cessation of dredging. Within the high dredging intensity site, recolonisation was relatively rapid after the cessation of dredging in 2003. Rather than indicating a full recovery, we suggest that this initial ‘colonization community’ may enter a transition phase before eventually reaching equilibrium. This hypothesis is supported by results from the low intensity site, where biological recovery was judged to have taken 7 years. Further monitoring is needed in order to test this. An alternative explanation is that the rapid recovery may be explained by the settlement of large numbers of Sabellaria spinulosa. As the resumption of dredging within the high intensity site limited our assessment of longer-term recovery it is not yet possible to assume that a 7-year biological recovery period will be applicable to other, more intensively dredged areas at this or more distant locations.  相似文献   

Physical impact on the reclamation area resulting from offshore dredging at the Changhwa coast, Taiwan     

Tai-Wen Hsu  Hsien-Kuo Chang 《Ocean Engineering》2001,28(2):235

The physical impact of offshore dredging on the reclamation area at the Changhwa coast, Taiwan, is investigated using a three-dimensional movable-bed model test. A distorted modeling law consisting of maintaining similarity of the equilibrium beach profile between the model and prototype is proposed. The geometric distortion was verified through a series of preliminary experiments conducted in a wave flume. Experimental results show that the distorted modeling is able to reproduce the beach-face slope in nature. An appropriate long-term morphological time-scale was determined based on a comparison of model longshore littoral transport rates and equivalent prototype values. Seabed topographical changes before and after offshore dredging are evaluated in model tests. A suitable countermeasure to prevent beach erosion from wave attack along the reclamation area is suggested from the experimental results.  相似文献   

Effects of Dredging Activities on Growth of Laminaria saccharina     

Jens Erik  Lyngby Sverre Mohr  Mortensen 《Marine Ecology》1996,17(1-3):345-354

Abstract. The possible effects of fine-grained deposits on the photosynthesis, growth, and nutrient uptake of Laminaria have been studied in field and laboratory experiments. Some of the plants were treated with fine-grained material for two hours and then transplanted in rows together with untreated plants. At two-week intervals the treatment was repeated and samples collected. The macroalgae were analyzed for growth as well as chlorophyll a , nitrogen, and phosphorus content. In the laboratory experiments, plants of a uniform size were incubated in Plexiglas containers after leaf-marking and treatment in a sediment suspension. At weekly intervals, photosynthesis, growth, chlorophyll a , and nutrients were analyzed.
The field study showed that Laminaria growth was significantly affected by the fine-grained material. The growth in the control experiment was 20% higher than in the treated plants. The chlorophyll a concentrations in the treated plants were significantly lower than in the control experiment, and the results indicated a reduced nutrient uptake in the treated plants. In the laboratory experiments the growth of the treated plants was only 30% of the controls, but no differences in photosynthetic capacities were detected. Nitrogen uptake was reduced in the treated plants, but no effects were observed on phosphorus uptake. Thick layers of fine-grained material caused direct harmful effects and rotting.
The results are discussed in relation to dredging activities; it is concluded that in heavy sedimentation areas, Laminaria growth may be significantly reduced beyond the indirect effect of shading from suspended material in the water.  相似文献   

栉孔扇贝(Chlamys farreri)外套膜一氧化氮合酶的研究     

孙虎山  王宜艳  王晓安  孙修勤  李光友 《海洋与湖沼》2007,38(2):174-179

采用组织化学、免疫组化和生物化学方法对栉孔扇贝外套膜中的一氧化氮合酶(EC1.14.13.39,NOS)活性进行了研究。组织化学显示结果表明,帆状部上皮细胞呈NOS强阳性,血细胞和神经纤维呈阳性;外套触手内有较多近圆形细胞和大量波浪形神经纤维呈NOS强阳性;边缘膜内有大量神经细胞和神经纤维分别呈NOS强阳性和阳性,外套环走肌束附近和血管内皮周围均有大量近圆形的强阳性细胞分布;中央膜有大量近圆形阳性细胞聚集成团块或分散分布。免疫组化显示表明,血细胞、帆状部和边缘膜上皮细胞呈神经型NOS(nNOS)和内皮型NOS(eNOS)弱阳性,而呈诱导型NOS(iNOS)阳性。生化测定结果表明,总NOS(tNOS)活力和一氧化氮(NO)含量均为中央膜最高,边缘膜次之,外套触手较低,帆状部最低,其中结构型NOS(cNOS)活力也是帆状部的最低,而iNOS活力则是外套触手的最低。栉孔扇贝外套膜可能是其神经系统中NOS的发生中心,NO-NOS体系可在其免疫防御和调节等方面发挥重要的作用。  相似文献   

栉孔扇贝(Chlamys farreri)中抗氧化肽的分离纯化及性质研究   总被引：6，自引：0，他引：6  

胡文婷  孙谧  王跃军 《海洋与湖沼》2006,37(1):14-19

以栉孔扇贝内脏团为原料,对其中抗氧化肽的制备、纯化及性质进行了研究。首先采用硫酸铵沉淀、DEAE-Sephadex A-50阴离子交换层析的方法,进行了扇贝提取蛋白的制备,其次采用海洋蛋白酶YS-80水解、SephadexG-25凝胶层析的方法,进行扇贝抗氧化肽的制备,获得多肽粗品(海洋肽,PCF),并进一步采用CM Sepharose阳离子交换层析和反相高效液相色谱的方法,对扇贝抗氧化肽进行了纯化,结果得到组分PCF-3A,反相高效液相显示为单一峰。采用茚三酮反应、Sephadex G-15凝胶层析和AccQ.Tag氨基酸分析柱,进行了PCF-3A的理化性质研究。结果表明,茚三酮反应呈阳性;分子量约为794D;由7种氨基酸组成,分别为天冬氨酸、甘氨酸、苏氨酸、丙氨酸、缬氨酸、赖氨酸和脯氨酸。采用邻苯三酚自氧化体系和Fenton反应体系对PCF-3A的抗氧化活性进行了研究,发现该肽可有效清除羟自由基和超氧阴离子,半抑制浓度(IC50)分别为0.39mg/ml和2.85mg/ml,具有明显的抗氧化、抗衰老作用。  相似文献   

Environmental geology: our professional public responsibility     

L. C. Gerhard  L. L. Brady 《Environmental Geology》1999,37(1-2):1-8

 Conflicts between different interest groups for use of natural resources is one area where state geological surveys can provide assistance. A state geological survey working within the scientific constraints of specific issues can remain objective in its presentations and maintain the faith of both the conflicting interest groups and the public. One cannot vary from the objective view or you will quickly be criticized. Criticism can still occur from one side of a natural resource issue as your data might counter their views. However, the final decisions are almost always made in some legislators, or regulators, area of responsibility. The responsibility of the state geological survey is to provide the important data that will assist in making correct decisions. Should one party in the conflict become extreme in their demands, a potential compromise that is beneficial to both sides can be lost. In Kansas, the classical natural resource problem of resource/recreation in a populated area is presented as a case study. The state geological survey presented data on sand resources in the Kansas River and its valley in northeast Kansas. That information was important to both recreation and dredging interests where the political problem is a conflict of sand use as a construction material resource versus use of the alluvial river as an important recreation area, especially for canoeing. However, when a reasonable compromise was near completion in the Kansas Legislature one side, in a bold move to develop an advantage, ruined that potential for compromise. Received: 12 May 1998 · Accepted: 6 July 1998  相似文献   

砂金矿床储量计算中若干问题的探讨     

尤恩沛 《吉林大学学报(地球科学版)》1987,(3)

本文对砂金矿床储量计算现存的某些问题提出了自己的看法,指出了由于不正确的计算方法给采金船生产带来的某些危害。着重论述了正确运用混合砂品位指标在矿床储量计算中的意义;单项钻孔工程混合砂品位表示方法、原则与采金船设计、生产的关系;关于矿体圈定中某些问题的处理。  相似文献