25 research outputs found
Drivers and barriers to sustainable fisheries in two peri-urban impoundments in Zimbabwe
Fisheries sustainability is categorised through four conceptual pillars: ecological, economic, and social, including cultural and institutional. Much work on fisheries sustainability has been done in marine fisheries relative to inland fisheries. Two inland peri-urban impoundments, Chivero and Manyame in Zimbabwe, support numerous small-scale fisheries; however, environmental and socioeconomic variables threaten the sustainability of the fisheries. This study aimed to identify and contextualise drivers and barriers to sustainability of small-scale fisheries in these two peri-urban impoundments. We applied three frameworks, Fishery Performance Indicators, Community-Based Fishery Indicators and FAO Small-Scale Fisheries Indicators, to identify and contextualise the drivers and barriers. Quantitative and qualitative methods were used to collect data from fishers in the two impoundments. A structured questionnaire was administered to 115 fishers in 23 fishing companies operating in the two lakes. Fisheries income and revenue as well as food security are key drivers. Lack of postharvest equipment, volatile fish markets, water quality and quantity deterioration and fish stock decreases are key barriers to sustainability of fisheries in the two impoundments. There are subtle differences in the extent and impact of the drivers and barriers of fisheries sustainability in the two lakes. The differences relate to the uniqueness of the aquatic habitats, social constructs and fisheries operational frameworks in each lake. This suggests a need to assess fisheries sustainability using an integrated bottom-up approach starting from individual fisheries < community fisheries < global/generic fisheries.Keywords: peri-urban fisheries, food security, water resource conservation, water pollution, sustainabilit
Voting as validation in robot programming
This paper investigates the use of voting as a conflict-resolution technique for data analysis in robot programming. Voting represents an information-abstraction technique. It is argued that in some cases a voting approach is inherent in the nature of the data being analyzed: where multiple, independent sources of information must be reconciled to give a group decision that reflects a single outcome rather than a consensus average. This study considers an example of target classification using sonar sensors. Physical models of reflections from target primitives that are typical of the indoor environment of a mobile robot are used. Dispersed sensors take decisions on target type, which must then be fused to give the single group classification of the presence or absence and type of a target. Dempster-Shafer evidential reasoning is used to assign a level of belief to each sensor decision. The decisions are then fused by two means. Using Dempster's rule of combination, conflicts are resolved through a group measure expressing dissonance in the sensor views. This evidential approach is contrasted with the resolution of sensor conflict through voting. It is demonstrated that abstraction of the level of belief through voting proves useful in resolving the straightforward conflicts that arise in the classification problem. Conflicts arise where the discriminant data value, an echo amplitude, is most sensitive to noise. Fusion helps to overcome this vulnerability: in Dempster-Shafer reasoning, through the modeling of nonparametric uncertainty and combination of belief values; and in voting, by emphasizing the majority view. The paper gives theoretical and experimental evidence for the use of voting for data abstraction and conflict resolution in areas such as classification, where a strong argument can be made for techniques that emphasize a single outcome rather than an estimated value. Methods for making the vote more strategic are also investigated. The paper addresses the reduction of dimension of sets of decision points or decision makers. Through a consideration of combination/order, queuing criteria for more strategic fusion are identified
PLANKTON AND MACROINVERTEBRATE COMMUNITY COMPOSITION IN THE PELAGIC AND NON-VEGETATED LITTORAL DRAWDOWN ZONES OF A SHALLOW RESERVOIR, MANJIRENJI, ZIMBABWE
Target identification with multiple logical sonars using evidential reasoning and simple majority voting
Drivers and barriers to sustainable fisheries in two peri-urban impoundments in Zimbabwe
Fisheries sustainability is categorised through four conceptual pillars: ecological, economic, and social, including cultural and institutional. Much work on fisheries sustainability has been done in marine fisheries relative to inland fisheries. Two inland peri-urban impoundments, Chivero and Manyame in Zimbabwe, support numerous small-scale fisheries; however, environmental and socioeconomic variables threaten the sustainability of the fisheries. This study aimed to identify and contextualise drivers and barriers to sustainability of small-scale fisheries in these two peri-urban impoundments. We applied three frameworks, Fishery Performance Indicators, Community-Based Fishery Indicators and FAO Small-Scale Fisheries Indicators, to identify and contextualise the drivers and barriers. Quantitative and qualitative methods were used to collect data from fishers in the two impoundments. A structured questionnaire was administered to 115 fishers in 23 fishing companies operating in the two lakes. Fisheries income and revenue as well as food security are key drivers. Lack of post-harvest equipment, volatile fish markets, water quality and quantity deterioration and fish stock decreases are key barriers to sustainability of fisheries in the two impoundments. There are subtle differences in the extent and impact of the drivers and barriers of fisheries sustainability in the two lakes. The differences relate to the uniqueness of the aquatic habitats, social constructs and fisheries operational frameworks in each lake. This suggests a need to assess fisheries sustainability using an integrated bottom-up approach starting from individual fisheries < community fisheries < global/generic fisheries
Drivers and barriers to sustainable fisheries in two peri-urban impoundments in Zimbabwe
Fisheries sustainability is categorised through four conceptual pillars: ecological, economic, and social, including cultural and institutional. Much work on fisheries sustainability has been done in marine fisheries relative to inland fisheries. Two inland peri-urban impoundments, Chivero and Manyame in Zimbabwe, support numerous small-scale fisheries; however, environmental and socioeconomic variables threaten the sustainability of the fisheries. This study aimed to identify and contextualise drivers and barriers to sustainability of small-scale fisheries in these two peri-urban impoundments. We applied three frameworks, Fishery Performance Indicators, Community-Based Fishery Indicators and FAO Small-Scale Fisheries Indicators, to identify and contextualise the drivers and barriers. Quantitative and qualitative methods were used to collect data from fishers in the two impoundments. A structured questionnaire was administered to 115 fishers in 23 fishing companies operating in the two lakes. Fisheries income and revenue as well as food security are key drivers. Lack of post-harvest equipment, volatile fish markets, water quality and quantity deterioration and fish stock decreases are key barriers to sustainability of fisheries in the two impoundments. There are subtle differences in the extent and impact of the drivers and barriers of fisheries sustainability in the two lakes. The differences relate to the uniqueness of the aquatic habitats, social constructs and fisheries operational frameworks in each lake. This suggests a need to assess fisheries sustainability using an integrated bottom-up approach starting from individual fisheries < community fisheries < global/generic fisheries.</jats:p
The relevance of integrating Ethno-Science (Indigenous knowledge) into Upper Primary Natural Sciences and Health Education School Curriculum in the Zambezi Region
There is widespread concern about the outcomes of science education in Namibian schools. The representatives of industries say that they need high-grade scientists, technicians and engineers if Namibia is to successfully compete in technology-intensive global markets by 2030. Ethno-science is a specialisation of indigenous knowledge (IK). It focuses on a scientific perspective of culture. The re-search that resulted in this article critically analysed the relevance of integrating ethno-science (IK) into the Upper Primary School curriculum in Namibia. The research further looked at how the people in the Zambezi region have developed a working terminology that produces taxonomies related to ethno-science. Research has shown that most anthropologists have carried out studies in ethno-science based on native perceptions. This research relies on a quantitative research approach in order to gather data from a population on the general understanding of ethno-science. It can also reveal that 10 parents were involved in the research. This research is of the utmost importance to the different sectors of the industry, teachers, learners, the National Institute For Educational Development (NIED), parents and institutions of higher learning as well as for the nation that needs to produce more science specialists at all level; a society that needs technicians as well as world-class researchers in order to increase the public’s ability to engage with scientific knowledge and choices
