Applications of unmanned aerial vehicles in Antarctic environmental research

Antarctica plays a fundamental role in the Earth's climate, oceanic circulation and global ecosystem. It is a priority and a scientific challenge to understand its functioning and responses under different scenarios of global warming. However, extreme environmental conditions, seasonality and isolation hampers the efforts to achieve a comprehensive understanding of the physical, biological, chemical and geological processes taking place in Antarctica. Here we present unmanned aerial vehicles (UAVs) as feasible, rapid and accurate tools for environmental and wildlife research in Antarctica. UAV surveys were carried out on Deception Island (South Shetland Islands) using visible, multispectral and thermal sensors, and a water sampling device to develop precise thematic ecological maps, detect anomalous thermal zones, identify and census wildlife, build 3D images of geometrically complex geological formations, and sample dissolved chemicals (< 0.22 µm) waters from inaccessible or protected areas.

Microbial life in oceanic crust

Oceanic crust comprises a vast but virtually unexplored habitat for life on Earth, characterized by massive global flows of water, heat, and dissolved chemicals. Uncovering where and how life exists in oceanic crust is important because chemical reactions occurring in this environment impact broader ocean systems and also because it is an earth analog for considering the possibility of extraterrestrial life on other ocean worlds. Over the past decade, several major oceanographic expeditions focused on characterizing the ocean crust microbiome, enabled by advances in seafloor drilling and observatory technologies. Here we review what is known about the crustal ocean microbial biosphere, focusing on a new synthesis of recent studies on the diversity of microbial life in oceanic crust to reveal common and unique taxa in this environment.

HYDROTHERMAL LIQUEFACTION OF MAHOGANY (Swietenia macrophylla) SAWDUST

Hydrothermal treatment is one of the thermochemical methods to convert complex organic compounds, such as organic waste and biomass, into upgraded solid, bio-oil, and other dissolved chemicals by utilizing the properties of water at near critical condition. Such method is very potential since the process is environmentally friendly and the products have more added values. In this research, conversion of mahogany sawdust (Swietenia macrophylla) using hydrothermal treatment method was studied. The experiments were conducted in a batch autoclave with temperature range of 200-300oC and initial pressure of 1 MPa. At targeted temperature, the process was hold for 30 minutes. In addition, biomass-water ratio (B/W ratio) for experiments was varied at 1:20, 2:20 and 3:20. The liquid products, which were characterized by Gas chromatography-Mass spectrometry (GC/MS) instrument, showed the presence of furfural and several organic acids, but no flavonoid compounds. Thus, coloring potential test of hydrothermal liquid was unsuccessful; there were not any color attached on the cloth specimen. On the other hand, proximate and ultimate test results indicated that solid products had high heating value (HHV) of 4625.34-4876.25 cal/g which were comparable to that of sub-bituminous coal.

The effects of phthalates on Nereis diversicolor

Animals are exposed, in the natural environment, to a range of human activity related dissolved chemicals that are potentially impacting on their fitness. The animals responses to such stress determines its fitness, physiology and in case of chemical signals also its behaviour. If physical or chemical changes in the ecosystem make the detection of such a chemical impossible, then it can be reasonably assumed that vital behaviours of the animal will be significantly altered. Plastics are lighter, more durable, stronger and cheaper than other materials used for the same purposes, making them most suitable for producing a very broad range of goods and products. However, these same properties also make them serious environmental hazards i.e. they are easily carried and dispersed by water over long distances, and stopped by barriers and settle in the form of sediments that can persist for centuries. Phthalate esters are widely used as additives to offer flexibility to polyvinyl chloride (PVC) resins (Graham, 1973). DEHP and DMP are the most frequently used plasticizer in PVC formulas in consumer products (Metcalf et al. 1973; Carnevali et al. 2010). In general phthalate esters harmful environmental and human health effects are well documented and a range of studies documented harmful effects on both land and aquatic organisms (Metcalf et al. 1973; Lithner, et al. 2009). Neanthes (Nereis, Hediste) diversicolor is a bio-indicator species to monitor levels of pollution in a particular environment i.e. to by quantify levels of contaminant presents in the worms. Measuring these in N. diversicolor makes it possible to estimate and monitor levels of contamination in marine environments. The worms are easy to keep in laboratory conditions and can be collected in large numbers in the field and used as model species since the 1950s (Scaps, 2002). The main aim of this study is to investigate and determine the fate of phthalates in a Nereis culture system and to assess the impact of phthalates upon fitness such as feeding behaviours. For this worms are exposed to different concentration of DEHP (0.05, 2, and 10 ug/mL) over short term (days) and long term (3 months / lifespan). The aim of short term of exposure was to determine the fate of phthalates in a Nereis culture system to examine if phthalate degradation takes place. GC-MS is used to measure the phthalates. Liquid: liquid extraction was used to extract phthalates from water and worm tissue whereas accelerated solvent extraction was used to extract phthalates from sediment. The aim of long term of exposure was to investigate and assess the impact of phthalates on animals’ functional traits (feeding response).

The effects of phthalates on Nereis diversicolor

Animals are exposed, in the natural environment, to a range of human activity related dissolved chemicals that are potentially impacting on their fitness. The animals responses to such stress determines its fitness, physiology and in case of chemical signals also its behaviour. If physical or chemical changes in the ecosystem make the detection of such a chemical impossible, then it can be reasonably assumed that vital behaviours of the animal will be significantly altered. Plastics are lighter, more durable, stronger and cheaper than other materials used for the same purposes, making them most suitable for producing a very broad range of goods and products. However, these same properties also make them serious environmental hazards i.e. they are easily carried and dispersed by water over long distances, and stopped by barriers and settle in the form of sediments that can persist for centuries. Phthalate esters are widely used as additives to offer flexibility to polyvinyl chloride (PVC) resins (Graham, 1973). DEHP and DMP are the most frequently used plasticizer in PVC formulas in consumer products (Metcalf et al. 1973; Carnevali et al. 2010). In general phthalate esters harmful environmental and human health effects are well documented and a range of studies documented harmful effects on both land and aquatic organisms (Metcalf et al. 1973; Lithner, et al. 2009). Neanthes (Nereis, Hediste) diversicolor is a bio-indicator species to monitor levels of pollution in a particular environment i.e. to by quantify levels of contaminant presents in the worms. Measuring these in N. diversicolor makes it possible to estimate and monitor levels of contamination in marine environments. The worms are easy to keep in laboratory conditions and can be collected in large numbers in the field and used as model species since the 1950s (Scaps, 2002). The main aim of this study is to investigate and determine the fate of phthalates in a Nereis culture system and to assess the impact of phthalates upon fitness such as feeding behaviours. For this worms are exposed to different concentration of DEHP (0.05, 2, and 10 ug/mL) over short term (days) and long term (3 months / lifespan). The aim of short term of exposure was to determine the fate of phthalates in a Nereis culture system to examine if phthalate degradation takes place. GC-MS is used to measure the phthalates. Liquid: liquid extraction was used to extract phthalates from water and worm tissue whereas accelerated solvent extraction was used to extract phthalates from sediment. The aim of long term of exposure was to investigate and assess the impact of phthalates on animals’ functional traits (feeding response).