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    ABSTRACT: In recent decades, the importance of marine aquaculture has grown substantially in most countries. Following a period of uncontrolled activities, the concern for the environmental implications of intensive mariculture has increased notably, and environmental impact is often taken into account when aquaculture activities are established. Among the most important pollutant effects of aquaculture are the outputs of dissolved nutrients, suspended solids and organic matter. In the present study, we have determined the loadings of dissolved nutrients (ammonium, nitrite, nitrate and phosphate), total suspended solids (TSS) and organic matter (particulate organic matter (POM) and biochemical oxygen demand (BOD5)) in the effluent of a marine fish farm devoted to the intensive culture of gilthead seabream (Sparus aurata) in earthen ponds. Samples of seawater were taken monthly during a two-year period (April 1997–March 1999) in the two inflows and the outflow of the fish farm. The environmental impact of marine aquaculture was established by estimating the total amount of each compound discharged into the receiving waters as a direct consequence of the culture activities. Thus, 9104.57 kg TSS, 843.20 kg POM, 235.40 kg BOD, 36.41 kg N–NH4+, 4.95 kg N–NO2−, 6.73 kg N–NO3− and 2.57 kg P–PO43−, dissolved in the seawater, were estimated to be discharged to the environment for each tonne of fish cultured.
    Marine Pollution Bulletin 11/2000; 40(11):981-988. DOI:10.1016/S0025-326X(00)00040-0 · 2.79 Impact Factor
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    ABSTRACT: Mangrove forests are of major ecological and commercial importance, yet the future of these resources is threatened by pollution, development and over-exploitation. There is an urgent need to develop sound management practices based on a functional understanding of the physical and biological processes underlying mangrove ecosystem dynamics. Such biological processes include dispersal (Rabinowitz 1978), herbivory (Smith 1987) and the physiological bases of species interactions and responses to environmental factors. Understanding these processes is essential for the development of more comprehensive and predictive modelling of mangrove ecosystem dynamics than has previously been possible.
    Trees 10/1988; 2(3):129-142. DOI:10.1007/BF00196018 · 1.87 Impact Factor
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    ABSTRACT: A procedure is described for obtaining allometric relationships between stem diameter and above-ground biomass for multi-stemmed trees of the mangroves Rhizophora stylosa and Avicennia marina. The procedure treats each stem as discrete tree that shares a proportion of the butt and other elements common to all stems. Linear log–log relationships were obtained between stem diameter and the dry weights of each above-ground component. Allometric relationships between stem diameter and total above-ground biomass were similar to those for single-stemmed trees in north-eastern Australia, but multi-stemmed trees on the west coast had much greater proportion of their biomass in the form of prop roots than single-stemmed trees of comparable stem diameter on the north-eastern coast. This is attributed to the arid environment on the north-western coast of Australia.
    Australian Journal of Botany 01/1997; 45(6). DOI:10.1071/BT96075 · 0.90 Impact Factor