{"id":{"repo_id":"cape-town","oai_identifier":"oai:open.uct.ac.za:11427/6174"},"canonical_url":"https://search.dev.ndltd.org/etd/cape-town/oai:open.uct.ac.za:11427/6174","repository":{"repo_id":"cape-town","name":"University of Cape Town","base_url":"https://open.uct.ac.za/oai/request"},"display":{"title":"Biological and economical feasibility studies of using seaweeds Ulva lactuca (Chlorophyta) in recirculation systems in abalone farming","abstract":"The aim of this study was to investigate whether a land-based recirculating seaweed-abalone integrated aquaculture system using Ulva lactuca was feasible as well as to test the differences between a commercial gravel bed recirculation system to an existing flow through system. These studies were carried out at two abalone farms: Danger Point (I & J) (140 km east of Cape Town) and at Jacobs Bay (JSP) (120 km north of Cape Town. South Africa). In both studies no significant difference in terms of water quality, abalone growth rates and abalone health were found. It was found that a seaweed /abalone recirculating system at the designed water exchange rates (25 %) was nitrogen limited and that the system as designed could be run at 75 % recirculation rate and remove a significant proportion of the dissolved nutrients (ammonium, phosphorus, nitrate and nitrite).","abstract_html":"The aim of this study was to investigate whether a land-based recirculating seaweed-abalone integrated aquaculture system using Ulva lactuca was feasible as well as to test the differences between a commercial gravel bed recirculation system to an existing flow through system. These studies were carried out at two abalone farms: Danger Point (I & J) (140 km east of Cape Town) and at Jacobs Bay (JSP) (120 km north of Cape Town. South Africa). In both studies no significant difference in terms of water quality, abalone growth rates and abalone health were found. It was found that a seaweed /abalone recirculating system at the designed water exchange rates (25 %) was nitrogen limited and that the system as designed could be run at 75 % recirculation rate and remove a significant proportion of the dissolved nutrients (ammonium, phosphorus, nitrate and nitrite).","abstract_has_math":false,"creators":["Robertson-Andersson, Deborah"],"institution":"Department of Biological Sciences","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Bolton, John J","Troell, Max","Probyn, T","Smit, A J"],"committee_chairs":[],"committee_members":[],"year":2006,"date_issued":"2006","date_published":"2006","updated_at":"2026-07-22T22:23:45Z","subjects":[],"languages":["eng"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/11427/6174","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Bolton, John J","Troell, Max","Probyn, T","Smit, A J"]},{"key":"dc:creator","label":"Author","values":["Robertson-Andersson, Deborah"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2014-08-13T14:07:29Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2014-08-13T14:07:29Z"]},{"key":"dc:date.issued","label":"Date","values":["2006"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["Department of Biological Sciences"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Cape Town"]},{"key":"dc:type","label":"Dc Type","values":["Doctoral Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["Doctoral"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["PhD"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/11427/6174"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Includes bibliographical references (p. 282-311)."]},{"key":"dc:description.abstract","label":"Abstract","values":["The aim of this study was to investigate whether a land-based recirculating seaweed-abalone integrated aquaculture system using Ulva lactuca was feasible as well as to test the differences between a commercial gravel bed recirculation system to an existing flow through system. These studies were carried out at two abalone farms: Danger Point (I & J) (140 km east of Cape Town) and at Jacobs Bay (JSP) (120 km north of Cape Town. South Africa). In both studies no significant difference in terms of water quality, abalone growth rates and abalone health were found. It was found that a seaweed /abalone recirculating system at the designed water exchange rates (25 %) was nitrogen limited and that the system as designed could be run at 75 % recirculation rate and remove a significant proportion of the dissolved nutrients (ammonium, phosphorus, nitrate and nitrite)."]},{"key":"dc:title","label":"Title","values":["Biological and economical feasibility studies of using seaweeds Ulva lactuca (Chlorophyta) in recirculation systems in abalone farming"]}]}],"canonical_facts":{"dc:contributor.advisor":["Bolton, John J","Troell, Max","Probyn, T","Smit, A J"],"dc:creator":["Robertson-Andersson, Deborah"],"dc:date.accessioned":["2014-08-13T14:07:29Z"],"dc:date.available":["2014-08-13T14:07:29Z"],"dc:date.issued":["2006"],"dc:description":["Includes bibliographical references (p. 282-311)."],"dc:description.abstract":["The aim of this study was to investigate whether a land-based recirculating seaweed-abalone integrated aquaculture system using Ulva lactuca was feasible as well as to test the differences between a commercial gravel bed recirculation system to an existing flow through system. These studies were carried out at two abalone farms: Danger Point (I & J) (140 km east of Cape Town) and at Jacobs Bay (JSP) (120 km north of Cape Town. South Africa). In both studies no significant difference in terms of water quality, abalone growth rates and abalone health were found. It was found that a seaweed /abalone recirculating system at the designed water exchange rates (25 %) was nitrogen limited and that the system as designed could be run at 75 % recirculation rate and remove a significant proportion of the dissolved nutrients (ammonium, phosphorus, nitrate and nitrite)."],"dc:identifier.uri":["http://hdl.handle.net/11427/6174"],"dc:language.iso":["eng"],"dc:publisher.department":["Department of Biological Sciences"],"dc:publisher.institution":["University of Cape Town"],"dc:title":["Biological and economical feasibility studies of using seaweeds Ulva lactuca (Chlorophyta) in recirculation systems in abalone farming"],"dc:type":["Doctoral Thesis"],"dc:type.qualificationlevel":["Doctoral"],"dc:type.qualificationname":["PhD"]},"updated_at":"2026-07-22T22:23:45Z"}