Hasintha Wijesekara - Runner up for BEST STUDENT POSTER COMPETITION at 2017 Mine Rehab ConferenceGlobal Centre for Environmental Remediation
I am a passionate PhD student from the University of Newcastle (UON). My thesis tittle is “Biogeochemical mechanisms of biosolids application on carbon sequestration in soils”. I use biosolids which is treated sewage sludge to limit greenhouse gas emission, and enhance soil carbon sequestration, thereby mitigating climate change. Before joining to the UON, I studied at University of South Australia (UniSA), Adelaide. I was fortunate to receive the prestigious International Presidential Scholarship (IPS) to conduct my Ph.D studies at the Center for Environmental Risk Assessment and Remediation, UniSA. I obtained B.Sc (Special) degree in Environmental Science and Natural Resources Management from University of Sabaragamuwa and M.Phil degree in Environmental Science from University of Peradeniya, Sri Lanka. I was a Research Assistant to the Chemical and Environmental Systems Modelling Laboratory, Institute of Fundamental Studies, Kandy. My hobby is disseminating science to Sri Lankan students in my native language.
|
Abstract
Microbeads In Biowastes.
Microbeads are plastic particles in the environment that are generally smaller than 1 mm down to the micrometer range. They are derived from a variety of sources, including cosmetics, clothing, and industrial processes. There are two sources of Microbeads: (i) primary microbeads are manufactured and are a direct result of anthropogenic use of plastic-based materials; and (ii) secondary microbeads are plastic fragments derived from the breakdown of larger plastic debris. Both types persist in terrestrial (i.e., soil) and aquatic (i.e., marine) ecosystems. Because plastics do not break down readily, they can be ingested and incorporated into and accumulated in the bodies and tissues of many terrestrial and aquatic organisms. UNEP (2016) identified that large quantities of microbeads ending up in the marine environment have originated from land-based sources. However, the majority of scientific research into microbeads has focused on their effects in aquatic environments. The results indicate that microbeads impact aquatic environments through long range transport of pollutants as a result of adsorption-desorption processes, as affected by the respective pollutant concentrations in a given area.
Terrestrial ecosystem is a major source of microbeads reaching aquatic ecosystem through sediment transfer during soil erosion. Microbeads reach terrestrial ecosystem through their indiscriminate disposal in landfills and also through biowastes application including biosolids and composts. There have been renewed interest in the large scale application of these biowastes especially to mine soils mainly to increase soil health and also to enhance revegetation of these disturbed soils. Although microbeads reach terrestrial environments, the degradation of many synthetic polymers is very slow and are likely to persist in soil over a long period of time. Along with physical breakdown, biologically initiated degradation also strongly influences chemical degradation. Adsorption and desorption processes of pollutants in microbeads in the soil environment are influenced by microbial activity. While the high surface area of microbeads not only aids adsorption/absorption of contaminants, but also supports chemical transport of the pollutants through leaching. In this presentation, the sources, fate, and environmental impact of biowaste-derived microbeads in terrestrial ecosystem will be examined. The paper will also aim to link the transport of microbeads from terrestrial ecosystem to aquatic ecosystem.
Co-authors: Hasintha Wijesekara 1, Lauren Bradney 1, Balaji Seshadri 1, Ramesh Thangavel 1, 2, Nanthi Bolan 1
1. Global Centre for Environmental Remediation (GCER), Advanced Technology Centre, Faculty of Science, The University of Newcastle, Callaghan, NSW, 2308, Australia
2. Division of Natural Resource Management, Indian Council of Agricultural Research (ICAR) Research Complex for North Eastern Hill Region, Umiam, Meghalaya, 793103, India
Microbeads In Biowastes.
Microbeads are plastic particles in the environment that are generally smaller than 1 mm down to the micrometer range. They are derived from a variety of sources, including cosmetics, clothing, and industrial processes. There are two sources of Microbeads: (i) primary microbeads are manufactured and are a direct result of anthropogenic use of plastic-based materials; and (ii) secondary microbeads are plastic fragments derived from the breakdown of larger plastic debris. Both types persist in terrestrial (i.e., soil) and aquatic (i.e., marine) ecosystems. Because plastics do not break down readily, they can be ingested and incorporated into and accumulated in the bodies and tissues of many terrestrial and aquatic organisms. UNEP (2016) identified that large quantities of microbeads ending up in the marine environment have originated from land-based sources. However, the majority of scientific research into microbeads has focused on their effects in aquatic environments. The results indicate that microbeads impact aquatic environments through long range transport of pollutants as a result of adsorption-desorption processes, as affected by the respective pollutant concentrations in a given area.
Terrestrial ecosystem is a major source of microbeads reaching aquatic ecosystem through sediment transfer during soil erosion. Microbeads reach terrestrial ecosystem through their indiscriminate disposal in landfills and also through biowastes application including biosolids and composts. There have been renewed interest in the large scale application of these biowastes especially to mine soils mainly to increase soil health and also to enhance revegetation of these disturbed soils. Although microbeads reach terrestrial environments, the degradation of many synthetic polymers is very slow and are likely to persist in soil over a long period of time. Along with physical breakdown, biologically initiated degradation also strongly influences chemical degradation. Adsorption and desorption processes of pollutants in microbeads in the soil environment are influenced by microbial activity. While the high surface area of microbeads not only aids adsorption/absorption of contaminants, but also supports chemical transport of the pollutants through leaching. In this presentation, the sources, fate, and environmental impact of biowaste-derived microbeads in terrestrial ecosystem will be examined. The paper will also aim to link the transport of microbeads from terrestrial ecosystem to aquatic ecosystem.
Co-authors: Hasintha Wijesekara 1, Lauren Bradney 1, Balaji Seshadri 1, Ramesh Thangavel 1, 2, Nanthi Bolan 1
1. Global Centre for Environmental Remediation (GCER), Advanced Technology Centre, Faculty of Science, The University of Newcastle, Callaghan, NSW, 2308, Australia
2. Division of Natural Resource Management, Indian Council of Agricultural Research (ICAR) Research Complex for North Eastern Hill Region, Umiam, Meghalaya, 793103, India
