Temporal And Spatial Changes In Water Quality In Lake Malawi/Niassa, Africa: Implications For Cage Aquaculture Management - Juniper Publishers

Juniper Publishers- Open access journal of Oceanography and Fisheries

Temporal And Spatial Changes In Water Quality In Lake Malawi/Niassa, Africa: Implications For Cage Aquaculture Management

Water temperature (WT), Secchi depth (SD), Percent dissolved oxygen (%DO), Dissolved oxygen (DO), Total nitrogen (TN), Total phosphorous (TP), and Chlorophylla (Chla) were measured in three sites, one at the farm (site 2) and two, 5 km northwest (site 1) and southeast (site 3) of the farm respectively, in February, April, June, and August 2012 to assess their spatial and temporal change in relation to cage aquaculture. There was clear seasonal change in % DO, DO, Chla, and SD at all sites. WT, % DO, and DO were consistently greater at site 1 than at site 3. Chla and SD were inversely correlated. The highest Chla and lowest SD occurred in April. The water was less clear at the farm, relative to the non-farm sites. Interestingly, this pattern was not seen in the Chla suggesting that decreased transparency at the farm was caused by some other factors in addition to Chla. DO, TP, and Chla are among the water quality parameters frequently used to assess aquaculture impacts. In this study, none of these indicators including the TN were consistently different at the study sites, suggesting that fish stocking densities present during the sampling period did not affect these water quality parameters; alternatively, it may suggest that high dispersion of nutrients mask the effect on water quality. However, water quality should be monitored at the farm during the upwelling period between April and July to avoid potential stress or fish kills..

 For more articles click on: https://juniperpublishers.com/ofoaj/OFOAJ.MS.ID.555552.php

Comments

Post a Comment

Popular posts from this blog

Bioluminescence in Fishes: Diversity and Functions- Juniper Publishers

                  Juniper Publishers -  Journal of Oceanography Introduction Bioluminescence is a amazing biological phenomen, which can be found in terrestrial and oceanic environments. Numerous bioluminescent taxa were described from the marine environment [ 1 - 2 ]. Bioluminescence is especially abundant in the deep-sea. The majority of luminescent taxa are invertebrate animals. In contrast to the high diversity in invertebrates, vertebrates lack bioluminescent light organs, with the exception of an amazing diversity in teleosts and some shark species. A recent paper reported that bioluminescence appeared in ray finned fishes in 27 independent evolutionary events [ 3 ]. Bioluminescent light is generated in spezialized light organs based on a oxyidation of a light emitting luciferine in the presence of oxygene and the enzyme luciferin [ 1 , 4 ]. Most of the bioluminescent species produce blue green light in the wavelength range around Xmax ~475nm [ 1 ]. Luminescence in fishes c
Read more

SDS-PAGE Electrophoresis of Ocypode rotundata Miers, 1882 and O. ceratophthalma Pallas, 1772 using Muscle Tissue along the Coast of Pakistan

Image
  Oceanography & Fisheries Open Access Journal Juniper Publishers Authored by Sahir Odhano Abstract Electrophoretic studies for the identification of ghost crabs (Ocypode rotundata and Ocypode ceratophthalma) using the SDS-PAGE were performed on protein patterns along the Sandspit coastal areas. The muscle tissues were used to estimate the molecular mass of proteins through SDS-PAGE electrophoresis. Electrophoretic settings were standardized to use 10% acrylamide resolving gel and 5% acrylamide stacking gel. A discontinuous buffer system was used following the protocols of Laemmli (1970) to observe the relative mobility and molecular weight of proteins. In O. rotundata total of 6 protein bands were resolved among them band-5 was found similar in size to the marker used (BSA = 66 kDa MW). Whereas in O. ceratophthalma total of 8 protein bands were resolved among them three protein bands (band-6, band-7, and band-8) were found to be higher in size than the molecular mar
Read more

Environmental Perception of Recreational Fishers in Urban Beaches

Image
  Oceanography & Fisheries Open Access Journal Juniper Publishers Authored by:  Jacqueline S Silva-Cavalcanti Abstract Recreational fishers depend on the good quality of those environments. The assessment of the environmental perception of social actors who show a sense of belonging to the landscape can better describe the impacts on the environment. This study aimed to assess the recreational fishers’ perception of the environmental quality in four urban beaches. 170 recreational fishers agreed to participate in the research. They were required to respond to questions about their fishing strategies and their perception of the environmental quality of the beaches and the possible impacts on the fishing activity. Based on the responses presented, a description of both local fishing activities made, as well as an analysis of the perception of the beaches’ environmental quality for fishers. On average, the recreational fisher ones have been working for 16.2 years. Pollu
Read more