Photosynthetic bacteria in the marine environment at Porto-Novo

Sediment and water samples were collected from mangrove and estuarine biotopes at fortnightly intervals. The physico-chemical characters of the overlying water were studied. In the mangrove biotope maximum temperature (31.5°C) and in the estuarine biotope maximum salinity (35.6‰) were recorded during the summer season, whereas in post-monsoon period the sulphate content was increased to 516 p.p.m. and the pH was reduced to 7.4. Invariably both in the enriched sediment and water samples four major peaks (at wavelengths 460, 705, 772 and 850 nm) and two minor peaks (at wavelengths 580 and 663 nm) of absorption spectra were noticed. A pure culture of Chromatium sp., isolated from mangroves sediment, showed three peaks of absorption spectra at wavelengths, 500, 580 and 850 nm. The effect of sodium chloride on the growth of Chromatium sp., was also studied and it was observed that maximum growth occurred in the range 1-3% sodium chloride concentration. This isolate was also capable of utilizing various sulphur and carbon compounds. Glycerol and glucose did not show any specific effect whereas pyruvate, malate and acetate increased the growth.

How is somatosensory information used to adapt to changes in the mechanical environment?

Recent studies examining adaptation to unexpected changes in the mechanical environment highlight the use of position error in the adaptation process. However, force information is also available. In this chapter, we examine adaptation processes in three separate studies where the mechanical environment was changed intermittently. We compare the expected consequences of using position error and force information in the changes to motor commands following a change in the mechanical environment. In general, our results support the use of position error over force information and are consistent with current computational models of motor learning. However, in situations where the change in the mechanical environment eliminates position error the central nervous system does not necessarily respond as would be predicted by these models. We suggest that it is necessary to take into account the statistics of prior experience to account for our observations. Another deficiency in these models is the absence of a mechanism for modulating limb mechanical impedance during adaptation. We propose a relatively simple computational model based on reflex responses to perturbations which is capable of accounting for iterative changes in temporal patterns of muscle co-activation.

A preliminary study on the protein requirement of Chanos chanos (Forskal) fry in a controlled environment

Growth rate of fish appeared to be related to the levels of the protein in the diet up to 40%. Fish fed diets containing 50 and 60% grew slower than those fed 40%, and the optimum level appears to be 40% when fed to fry at a rate of 10% of body weight. Best feed conversion of 1.96 was also obtained from the 40% protein diet. Mean survival rates were low in all treatments, but highest for the 40% protein diet. The competition of 5 isocaloric experimental diets containing various levels of protein are tabulated, as are weight gains, diet conversions and survival rates for milkfish fry fed various dietary levels of protein. Growth curves for milkfish fry are shown, and the relationship between weight gains of milkfish fry and the dietary levels of protein are illustrated.

Fisheries, marine environment, and integrated coastal management policy processes, content and implementation in the BOBLME countries: regional synthesis and country questionnaires

This paper examines policy processes, policy trends and policy implementation with regards to capture fisheries, the marine environment and Integrated Coastal Management (ICM) in BOBLME countries. Individual country information was analyzed to generate a regional synthesis.

Shrimp culture and the environment

The paper discusses the impacts of shrimp culture to the environment in some countries in Asia. Specifically, it highlights the land requirements suitable for shrimp farming and the impacts of shrimp culture on mangroves. The positive effects of mangroves such as its filtering capacity and as a protective buffer are also discussed.

Go for environment friendly aquaculture

The article presents environment friendly aquaculture practices such as semi-intensive aquaculture, the culture of native species, the selection of proper sites for aquaculture facilities, the conduct of thorough, honest socioeconomic and ecological impact assessment before proceeding with the implementation, and the practice and promotion of proper pond/cage/tank preparation and management among others.