Heartbeat and respiration of southern elephant seals (Mirounga leonina), Weddell seals (Leptonychotes weddellii) and Antarctic fur seals (Arctocephalus gazella) were monitored simultaneously using a visual and non-intrusive method, at King George Island, South Shetland Islands. All three species demonstrated sleep apnoea with reduced heart rate. In adult elephant seals, heartbeat fell 18% in apnoea; spells lasted up to nine min, usually ending in disturbance from conspecifics or human visitors. Slight human disturbance (notably slight noise) reduced time spent in apnoea from over 40% to 4%, significantly reducing the frequency of falling into apnoea and increasing mean heartbeat. Further disturbance resulted in head raising, aggression, scratching, rolling and movement away. The visual monitoring of heartbeat and respiration can be used with resting or slightly disturbed animals but not when major body movements occur.
This study applied a modified OxiTop® system to determine the oxygen uptake rate during a 2-day respiration test of selected composting materials at different moisture contents, air-filled porosities and composition of composting mixtures. The modification of the OxiTop® respirometer included replacement and adjustment of a glass vessel (i.e. a 1.9-L glass vessel with wide mouth was used instead of a standard 1-L glass bottle, additionally the twist-off vessel lid was adjusted to attach the measuring head) and application of a closed steel mesh cylinder of 5 cm in diameter and 10 cm in height with the open surface area of the mesh of approximately 56.2%. This modification allowed obtaining different bulk densities (and thus air-porosities) of the investigated composting materials in laboratory composting studies. The test was performed for apple pomace and composting mixtures of apple pomace with wood chips at ratios of 1:0.5, 1:1, 1:1.5 (d.w), moisture contents of 60%, 65% and 75% and air-filled porosities ranging from 46% to 1%. Due to diverse biodegradability of the investigated apple pomace and composting mixtures this test allows for the determination of the effects of different air-porosities (due to compaction in a pile) on the oxygen uptake rate for mixtures with a fixed ratio of a bulking agent. The described method allows for laboratory determination of the effects of moisture content and compaction on biodegradation dynamics during composting.
With the increase of agricultural production, residues of crop are the main source of organic matter in the soil and they are alternatives to inorganic fertilizers. For this purpose, effects of organic residues (cotton stalk, maize stalk, almond bark) commonly grown in Turkey were investigated for some soil microbial activity in clay soil. In this study, incubation experiment was set up. Five doses (0%, 2%, 4%, 6% and 8%) of organic residues (maize stalks, cotton stalks or almond bark) were applied to soil. Soil microbiological properties of soil samples such as CO2 respiration, dehydrogenase and urease activity were determined. According to the results obtained, maize stalk, cotton stalks and almond bark applications increased some soil microbiological activities, such as CO2 respiration, dehydrogenase and urease activities according to control soil. Maize stalk in comparison to other residues affects better on the biological properties of the soil. It is determined that enhancing effects of the added organic residues (maize stalk, cotton stalk, almond bark) into the soil were changed according to the type of organic residues, dosage and application terms.
Operations conducted by petroleum industry generate an entire range of drilling waste. The chemical composition of drilling waste and its toxicity depend primarily on the geological and technological conditions of drilling, the type of drilled rock deposits and on the type and composition of the drilling mud used. In the course of drilling operations, drilling fluids are in constant contact with bacteria, fungi and other organisms infecting the mud. Pioneer species, capable of surviving and using the resources of this specific environment, are selected. For this reason, the effectiveness of microbiota survival on different types of spent drilling muds and in different dilutions with brown soil was measured. Spent drilling muds samples came from drilling operations in various regions of Poland, e.g. Subcarpathia, the Polish Lowland and Pomerania regions. Oxygen consumption after 96 h was around 20 μg·g‒1 dry mass in soil or soil/drilling water-based mud mixture. Soil mixes contained 10 wt% synthetic base, mud had a higher oxygen consumption – 38 μg · g‒1 dry mass. Oxygen consumption decreases sharply as the content of the spent synthetic base mud fraction increases. A higher concentration of spent SBM (35 wt%) reduced the aerobic metabolism by slightly more than 50%. A high concentration of reduced carbon decreased the respiratory quotient (RQ) value to 0.7. All the researched drilling waste shows microbiological activity. At the full concentration of drilling fluids and non-dilution options, the chemical composition (salinity, inhibitors, etc.) strongly inhibits microbiota development and consequently, respiration