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1.
微藻应用的潜力及途径 总被引：8，自引：0，他引：8
一、前言地球上有30，000余种微藻，但人类培养与利用的种类相当有限[14]，而且只有几十年的历史[8]。尽管如此，目前国际上微藻应用已进入商业性生产阶段[2][14][28][38]。在我国，微藻应用由五十年代末的代食品、代饲料[37]拓展到今天广泛的领域，主要有：（1）固氮兰藻作为生物肥料，单细胞蛋白（SCP）源等[8][11][25]，并有了一整套培养技术；（2）作为海产经济动物鱼、虾、贝等幼体或成体的直接或间接活饵料[8][23][31][32]；（3）以螺旋藻（Spirulina）为代表的作为人类营养、保健和医疗制品[1][18]。钝顶螺旋藻（Spirulinaplatensi… 相似文献
2.
关于控制水体中重金属含量的因素,六十年代以来文献陆续有所报导.在海水体系中粘土矿物对重金属的固定作用的研究,较早期的有Chester(1965)的伊利石吸附海水中钴和锌的研究.近五年来又见有Rermers[1]、Murray[2]、Meyers[3]、O'conner[4]、Weijden[5]以及Robin[6]等进一步分别探讨了粘土矿物对重金属吸附作用的影响因素、吸附能力及吸附动力学等问题,其中有的还提出了吸附作用的模式. 相似文献
3.
多细胞海藻的遗传学研究现在还处于幼令时期。就绿藻讲,Field等曾讨论过易变石莼(Ulva mutabilis)的若干突变对个体发育的影响[1]。在红藻中,Van der Meer等记载了江篱(Gracilaria)的色素突变型[2],三浦昭雄(Miura)等记载了紫菜(Porphyra yezoesfis)的色素突变型[3],它们都表现了孟德尔的遗传规律,Waaland对产生卡拉胶的杉藻(Gigartina exasperata)进行了育种实验[4]。 相似文献
4.
沈毓毅 《中国海洋大学学报(自然科学版)》1982,(4)
引言 在科学研究中,往往会提出一个系统关于部分变元的稳定性,这可以参考[1]。在随机控制问题中,也提出一个随机系统关于部分变元的稳定性,这可以参考最近的文献[2]。本文作者在[3][4]中分别讨论了有色噪声随机系统与Ito随机系统关于部分变元运动稳定性,[2][3][4]都是用李雅普诺夫函数的方法,本文从另外一个角度来研究Ito随机系统的部分变元稳定性。中心思想是把高维系统的问题归结为较低维的系统的 相似文献
5.
6.
本文描述了从青岛海边分离的数种螺旋藻的形态与分类 按照文献[1][2][3][4][5][6][7][8][9]标准种形态的描述,本研究室藻种号MACC/Y146被定为Spirulina versicolor,MACC/Y171被定为S.subtilissima,MACC/Y38被定为S.subsalsa,MACC/Y133被定为Spirulina sp.其中MACC/Y146,MACC/Y133我国尚未报导 以上各种均系单克降培养 相似文献
7.
划分变性水团边界的温盐点聚对照法与东海西部海区变性水团的分析 总被引：6，自引：2，他引：6
分析水团已有许多方法,其中多数是分析大洋水团问题的[3][4][5][6][7][8],用于浅海有一定困难;关于分析浅海水团问题、我国进行了一些研究[1][2],主要解决确定水团边界问题.其中“组成比例法”能比较定量地确定出水团边界的位量,但这个方法要求参加混合的水团要有明确的核心值.由于水团的核心值难于确定,特别是在不同季节调查海区范围经常变动的情况下,若把被调查海区内温盐的极值当作核心值来处理.必然影响到比例中点的相应变动,所确定的水团边界也就不准确了. 相似文献
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9.
一、引言 在随机控制问题中常需要研究Ito随机微分方程的稳定性。 对于Ito方程的李雅普诺夫稳定性已有许多作者研究过。例如参考[1][2]。在确定性的情况,在某些问题中,只要求对x(t)的某些分量稳定性就可以了。于是有关于部分变元稳定性的研究。这个问题首先由李雅普诺夫在其原著中提出。于1957 相似文献
10.
沈毓毅 《山东海洋学院学报》1982,12(4):69-76
在科学研究中，往往会提出一个系统关于部分变元的稳定性，这可以参考[1]。在随机控制问题中，也提出一个随机系统关于部分变元的稳定性，这可以参考最近的文献[2]。本文作者在[3][4]中分别讨论了有色噪声随机系统与Ito随机系统关于部分变元运动稳定性，[2][3][4]都是用李雅普诺夫函数的方法，本文从另外一个角度来研究Ito随机系统的部分变元稳定性。中心思想是把高维系统的问题归结为较低维的系统的问题。在第一节中引进一种直接估计解的方法，把n维Ito随机系统关于m维(m≤n)的均方指数稳定性或不稳定性，归结为一个m维随机系统的均方指数稳定性或不稳定性。在第二节中，我们把这一思想推广到大系统问题中，得到一个由各个孤立子系统的稳定性判定复合系统稳定性的结果。 相似文献
11.
《African Journal of Marine Science》2013,35(2):269-281
Fish were surveyed by visual census on offshore reefs in Mozambique and eastern South Africa to compare (a) fully-protected ‘sanctuary’ areas, (b) ‘partly protected’ areas where recreational diving and limited fishing are permitted, and (c) ‘open’ unprotected areas. Community composition differed between coral-dominated reefs and those covered mainly by algae and sponges, but not among treatments. Larger size classes were significantly diminished in unprotected areas compared to protected and sanctuary zones. Within coral-dominated reefs, abundances of indicator taxa showed three patterns: (1) greatest abundance in sanctuaries, intermediate in partly protected and least in open areas; (2) greatest abundance in sanctuaries but equal diminishment in partly protected and open areas; and (3) greater depletion in partly protected than either sanctuary or open areas. We conclude that partial protection does not effectively conserve reef fish, and there are indications that partly protected areas concentrate fishing effort on ‘pelagic’ gamefish. Sanctioned shore-angling and offshore ‘gamefishing’, illegal fishing and diver disturbance may collectively undermine the efficacy of partially protected areas. The depletion of reef fish species inside protected areas and reconsideration of the classification of pelagic gamefish require managerial attention. Partly protected areas in Mozambique need to be supplemented with no-take zones. 相似文献
12.
Recently, how different attributes influence the price of fish has received increased attention. This is partly due to the perceived impact of different attributes on quality and price, but lately environmental concerns are also playing a part. In contrast to earlier studies that focus on the Ex-Vessel or retail level, this study investigates wholesale data, for hake in Spain. The wholesale data provide information on a wide range of origins as the hake market has increasingly become global. The empirical analysis is conducted by estimating a hedonic price function. The results indicate that while fishing gear and size are important attributes, the origin of the fish is in this case the clearly most important attribute in determining the price. The price more than doubles for fish from the most preferred source, Catalonia, relatively to the fish from the least preferred source, Namibia. 相似文献
13.
Thedietsofthealpinegalaxias(Galaxias paucispondylus Stokell, 1938) and the longjawed galaxias (G. prognathus Stokell, 1940) were studied in Deep Creek, a high‐country stream in the central South Island of New Zealand. Both species are small, slender fish with entirely freshwater life cycles. Their diets were very similar and consisted of aquatic invertebrates, dominated by the larvae of Deleatidium spp. (Ephemeroptera), Hydrobiosis spp. (Trichoptera), and Chironomidae (Diptera). Although diets partly reflected what was available in the stream, both fish selected soft‐bodied prey in preference to cased or harder shelled prey. Both species are probably nocturnal feeders. 相似文献
14.
L. J. Paul 《新西兰海洋与淡水研究杂志》2013,47(2):273-292
Scales from 17 body areas of juvenile snapper, Chrysophyrs auratus (Forster), were examined to determine scale growth characteristics, with the aim of denning the most suitable body site for routine scale‐sampling. Least‐square regressions of fish length on scale measurement from 0+ fish were calculated for several body areas, and back‐calculations were made to fish length at first annulus (L1) from a sample of 1+ fish, using both the “uncorrected” and “corrected” formulae. The overall fish/scale relationship is curvilinear, but high correlation coefficients show that fish/scale regressions from 0+ snapper may be taken as essentially linear. Such regressions give hypothetical fish lengths at scale formation of 8–23 mm. Mid‐body scales form at 10–14 mm, caudal scales earlier, head scales later. Back‐calculated L1 values from each area were compared with the mean for the whole body. Using the uncorrected formula there is a general trend for them to be lower than the mean at the head and higher at the tail, while the mid‐body region shows minimum variation from the mean. These variations are caused at least partly by differences in time of scale formation. The corrected formula gives smaller L1 variations and a mean back‐calculated L1almost identical to an observed L1 from independent length frequency data. The observed variations in scale structure and growth suggest that the “pectoral area”, bounded by the lateral line and the ventral edge of the pectoral fin, is the most suitable site for scale sampling. 相似文献
15.
《Marine Policy》2014
This study examined the perceptions of fishers from two fishing communities with differing use histories and involvement in the long-standing (16 yr) multiple use Mafia Island marine protected area (MIMP), Tanzania. A randomly distributed questionnaire indicated that 94% of fishers believed that without the MIMP, there would be overfishing, dynamite use, destroyed habitats, and few fish. Fishers were more positive about core zones (no-take fishery closures) than general use zones (areas allowing selective fishing) as a consequence of increases in fishing pressure. Those that reported increased catches and sizes of fish since the creation of the MIMP were more likely to agree with present zone locations and more positive in general about fisheries and conservation planning. Most thought that fish size and gear restrictions were preferable to permanent closures. Perceptions differed among communities and gear users. Community and gear type explained 46% of the variance in responses about the perception that fisheries and conservation are compatible goals. Somewhat surprisingly, these effects were more important than catch increases or involvement in MIMP-related activities. The differences in perception between communities may be partly attributed to different fishing histories. Multiple-use zoning provides a means to identify and resolve conflicts and achieve what are likely universal objectives for fisheries sustainability and conservation. 相似文献
16.
A suite of general physiological indicators and hepatic biomarker responses were determined in red mullet (Mullus barbatus) from priority pollution areas of W Mediterranean Sea, including the highly metal polluted area of Portmán (Cartagena, SE Spain). Concentrations of metals and persistent organic pollutants in fish muscle tissue and sediment samples were also analysed. Our results showed that fish from Portmán accumulated the highest concentrations of mercury, lead and arsenic and also of some polycyclic aromatic hydrocarbons and polychlorinated biphenyls congeners. In addition, they had significantly lower condition factor, muscle lipid content and gonadosomatic index, as well as the lowest levels of DNA integrity and the highest ethoxyresorufin-O-deethylase (EROD) activity in liver of the areas investigated. Contaminant body burden in fish only partly corresponded to chemical characteristics of the sediments in the areas in which they were collected. Our findings indicate that red mullets from Portmán had suboptimal health status that warrant further study. 相似文献
17.
《Ocean & Coastal Management》2003,46(6-7):527-545
In this paper, we address the implications of changing social-ecological feedback links for a sustainable management of coastal regions applying an ecosystem management perspective. This case study focuses on user patterns of fish resources in the Central Baltic Sea archipelago consisting of three sub-regions: Stockholm archipelago, Sweden, the Åland islands and the archipelago of SW Finland. The transition from a region, mainly relying on a mixture of local natural resources towards a region more dominated by the recreational demands of nearby large urban areas, has altered user patterns of fish resources. This transition has partly followed different pathways in the three sub-regions depending on how socio-economic driving forces have been manifested in management actions. Nevertheless, functioning ecosystems are still the basis for the delivery of ecosystem services and a living archipelago system. The significance of capturing and (re)building feedback links into management regarding knowledge on ecosystem services for a sustainable ecosystem management is discussed. 相似文献
18.
Sirpa Huuskonen Tiina Rsnen Kari Koponen Pirjo Lindstrm-Sepp 《Marine environmental research》1995,39(1-4)
Hepatic monooxygenase enzyme activities and relative cytochrome P4501A protein content were measured to evaluate the time-course alterations in rainbow trout after change in living habitat. Fish were transferred from one fish farm to the tanks of another hatchery and/or into cages kept in a lake. In the new habitats, cytochrome P450-dependent enzyme activities in rainbow trout decreased, and were at their lowest levels after two or three weeks in the summer. Later the activities partly reversed. The immunodetection of cytochrome P4501A protein expressed a similar trend as for catalytic monooxygenase activities. 相似文献
19.
Augustine W. Mwandya Martin Gullström Marcus C. Öhman Mathias H. Andersson Yunus D. Mgaya 《Estuarine, Coastal and Shelf Science》2009
Deforestation of mangrove forests is common occurrence worldwide. We examined fish assemblage composition in three mangrove creek systems in Tanzania (East Africa), including two creeks where the upper parts were partly clear-cut of mangrove forest due to the construction of solar salt farms, and one creek with undisturbed mangrove forest. Fish were caught monthly for one year using a seine net (each haul covering 170 m2) within three locations in each creek, i.e. at the upper, intermediate and lower reaches. Density, biomass and species number of fish were lower in the upper deforested sites compared to the mangrove-fringed sites at the intermediate and lower parts in the two creeks affected by deforestation, whereas there were no differences among the three sites in the undisturbed mangrove creek system. In addition, multivariate analyses showed that the structure of fish assemblages varied between forested and clear-cut sites within the two disturbed creeks, but not within the undisturbed creek. Across the season, we found no significant differences except for a tendency of a minor increase in fish densities during the rainy season. At least 75% of the fishes were juveniles and of commercial interest for coastal fisheries and/or aquaculture. Mugil cephalus, Gerres oyena and Chanos chanos were the most abundant species in the forested sites. The dominant species in the clear-cut areas were M. cephalus and Elops machnata, which were both found in relatively low abundances compared to the undisturbed areas. The conversion of mangrove forests into solar salt farms not only altered fish assemblage composition, but also water and sediment conditions. In comparison with undisturbed areas, the clear-cut sites showed higher salinity, water temperature as well as organic matter and chlorophyll a in the sediments. Our results suggest that mangrove habitat loss and changes in environmental conditions caused by salt farm developments will decrease fish densities, biomass and species numbers as well as alter the overall fish assemblage composition in the salt farm area but not downstream in the creek. 相似文献
20.
《African Journal of Marine Science》2013,35(1):391-414
A balanced trophic flow model of the southern Benguela ecosystem is presented, averaging the period 1980–1989 and emphasizing upper trophic levels. The model is based largely on studies conducted within the framework of the Benguela Ecology Programme and updates the results of an expert workshop held in Cape Town in September 1989. Small pelagic fish other than anchovy Engraulis capensis and sardine Sardinops sagax, mainly round herring Etrumeus whiteheadi and mesopelagic fish, were important components of the food web in the southern Benguela. Severe balancing difficulties were encountered with respect to the semi-pelagic resources (hake Merluccius spp.) and demersal top predators (sharks), indicating the need for further research on the interaction of these groups with their ecosystem. The model is compared to other existing trophic flow models of ecosystems in major upwelling areas, i.e. the northern Humboldt Current (4–14°S), the California Current (28–42°N) and the southern Canary Current (l2–25°N), and to two independently constructed models of the northern Benguela ecosystem. These models are compared using network analysis routines of the ECOPATH software, focusing on the interactions between the five dominant fish species (anchovy, sardine, horse mackerel Trachurus trachurus capensis, chub mackerel Scomber japonicus and hake) that support important fisheries in all systems. The upwelling systems rank by size rather than species dominance. The ratio of catches and primary production differs between systems, partly because of differences in fishing regimes. Predation on the five dominant fish groups by other fish in the system was the most important cause of fish mortality in all models. Fishery catches are generally a larger cause of mortality for these groups than predation by mammals. The ecological cost of fishing appears to be comparatively low in the southern Benguela, because catches are low compared with the primary production, but also because the fishery is relatively low in the foodweb. However, in view of the very tight foodweb demonstrated in the model. it is likely that an increase in fishing pressure would cause severe trade-offs with respect to other components of the southern Benguela ecosystem. 相似文献