Reproductive biology of Ruditapes decussatus (Linnaeus,1758) in Çardak Lagoon, Dardanelles Strait
Ahmet Mutlu Gözler, Ahmet Nuri Tarkan
Karadeniz Technical University, Faculty of Aquatic Products, Rize,TURKEY
University of Istanbul, Faculty of Aquatic Products,Department of Marine Biology, Ordu Caddesi, No. 200, Laleli 34470 Istanbul, TURKEY
Abstract
This study was carried out in order to determine the reproductive period of the carpet clam (Ruditapes decussatus L. 1758). 43.32 % of the examined clams were the females, and 34.38 % were the males and the sex ratio was 1:1,23. Microscopical investigations indicated that the early spawners appeared in March-April. The gonad development started in March and spawning took place between July and October. Histological examinations revealed that gonad development started in March and terminated in October. The period between November and March was the resting stage of clam. The number of ripened individuals made a pike in June. Condition Index results were almost parallel with those of histological examinations. Determinations of temperature, salinity and chlorophyll-a revealed that Ruditapes decussatus spawned at 24˚C temperature and a salinity value between 20-26 ‰.
Keywords: Ruditapes decussatus, reproductive biology Çardak Lagoon, Dardanelles Strait
Coastal aquaculture: Sustainable development, resource use and integrated environmental management
Ibrahim Okumuş
KTU Faculty of Marine Sciences, Department of Fisheries, 61530 Çamburnu, Trabzon, TURKEY
Abstract
With a dramatic expansion over the past two decades, aquaculture has now become a world-wide aqua-industry and kept the global fisheries production increasing despite the levelling off the capture fisheries. Annual production from this new industry now approached to 30 million tonnes, while the captures fisheries almost levelled off around 90 million tonnes. Inland aquaculture still continues to play a significant role, but rapidly developing coastal aquaculture produced 43.1% of aquaculture output in 1997. However, aquaculture is not only a producer of aquatic food but also a consumer competing for infinite resources and rapid development brought some problems as well. Therefore, sustainable development such a. rate to compensate and ultimately supplement the traditional fisheries in new millennium depends on addressing resource allocation and. environmental interactions within the broader framework of integrated environmental management programmes. This article reviews the recent developments in coastal aquaculture and discusses the available resources and constraints limiting the sustainable development. In particular, the way in which coastal aquaculture interact with the environment has been evaluated.
Keywords: Mariculture, developments, constraints, environmental effects, coastal management
Oil pollution in Tuzla Bay after TPAO Tanker accident
Selma Ünlü, Kasim Cemal Güven, Ertugrul Dogan, Erdogan Okus
University of Istanbul, Institute of Marine Sciences and Management, Vefa, 34470, Istanbul, TURKEY
Abstract
The oil pollution was investigated in seawater, sediments and mussels in Tuzla Bay after the TPAO tanker accident. 214.3 ton oil was spilled and 250 ton oil burnt. The pollution level was determined in seawater, sediments and mussels after the accident. The highest pollution was found as 33.2 mg/L in seawater, 423.01µg/g in sediment on the first day after the accident and 2067µg/g in mussels 1 month after the accident. The pollution level decreased during the survey of 14 Feb 1997 to 13 Feb 1998.The origin of oil in seawater, sediments and mussels were identified by using fingerprinting analysis technique.
Keywords: Oil pollution TPAO tanker accident, crude oil, Tuzla Bay
