Bioventing can be effective for the remediation of soil contaminated with petroleum hydrocarbons. However, implementing laboratory results in field scenarios is difficult due to the lack of scale-up factors. Accordingly, laboratory bioventing experiments were undertaken at the meso-scale and then compared with previously completed micro-scale tests to evaluate the important scale-up factor. The developed meso-scale system holds 4 kg of soil, with bioventing conditions controlled from a nutrient, airflow, and water content perspective. Three soils were tested, and categorized as loamy sand, silt loam, and a mixture. Results over a 30-day period showed a two-stage degradation pattern that encompassed first-order degradation rates as compared with the single-stage first-order degradation rate determined in the micro-scale study. For the first stage (0-8 days), the degradation rate for loamy soil was 0.598 day −1 , with the silty soil at 0.460 day −1 , and mixed soil at 0.477 day −1 . After 8 days, the degradation rate constant for the loamy soil dropped to 0.123 day −1 , with the silty soil dropping to 0.075 day −1 , and the degradation rate for the mixed soil dropping to 0.093 day −1 . Comparison of the measured degradation rate values with the results from the micro-scale experiments gave scale-up factors varying from 1.9 to 2.7 for the types of soil considered in the current study. These differences in degradation rates between the two scales show the importance of scale-up factors when transferring feasibility study results to the field.

Contrary to the constraints in time, investment, and management of the traditional technology for waste water treatment, this paper seeks to propose a more advanced, reliable, and affordable new technology to restore urban polluted rivers to pristine quality levels. The paper also presents new ideas on the selection and use of microbial agents to improve the efficiency of pollution removal. It presents the successful implementation of microbial technology (MT) on Chengnan River, which was heavily polluted before MT implementation. Without artificial aeration, sediment dredging, or complete sewage interception, we directly sprayed a previously configured HP-RPe-3 Microbial Agent into the water body and sediment. We considered the feasibility of MT for treating polluted urban rivers from the perspective of several water quality indices evaluation methods. After the treatment, the concentration of dissolved oxygen (DO) reached 5.0 mg/L, the removal rates of ammonia nitrogen (NH 3 -N) and chemical oxygen demand (COD) reached 20% and 38% respectively, and the average degradation rate of total phosphorus (TP) along river was close to 15%. Also, the Nemerow Index of the river was reduced from 2.7 to 1.9. The Fuzzy Comprehensive Index shows a tendency for improvement from Inferior Grade V to a better grade (approximately Grade III). The color of the river water changed, from black or dark green, to its original color. The results indicate that the bioremediation technology of directly adding microbial agents mainly aimed for the degradation of NH 3 -N can preliminarily eliminate the black-odor phenomenon of urban rivers, and improve their water quality. It is expected that the MT application, and the concept of how to select the corresponding microbial agents according to main pollutants, can be widely accepted and applied to similar cases.

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Cereals are staple food for many countries and are grown on millions of hectares of land, but much of the harvest is wasted due to losses by pests. To minimize these losses, many pesticides are used which are damaging to the environment and human health. There are debates to get rid of these chemicals but they are still in use at large scale. An alternative control strategy for insect pests in storage houses is the use of botanicals. In this study, four plant essential oils, two plant extracts, two herbicides, and two insecticides were used against Tribolium confusum and the comparison of toxicity was made by calculating LC50 and LT50 values. LC50 values were higher for abamectin (2.09–10.23 mg/L) and cypermethrin (3.41–11.78 mg/L) insecticides followed by neem essential oil (7.39–19.24 mg/L) and citrus extract (10.14–24.50 mg/L). However, LC50 values were maximum in case of jaman plant extract (22.38–176.42 mg/L) followed by two herbicides, Logran (19.66–39.72 mg/L) and Topik (29.09–47.67 mg/L) However, LC50 values were higher for topic herbicide (24.098 ppm) and jaman essential oil (16.383 ppm) after four days of treatment. Abamectin and cypermethrin insecticides, neem essential oil and citrus plant extract also killed adults of T. confusum quicker as compared other essential oils, extracts and herbicides. Results revealed that botanical formulations being environmentally safe could be used instead of highly hazardous pesticides for stored products’ pests. This study also elaborates the non-host toxicity of herbicides commonly applied in our agroecosystem.

Punjab, Pakistan is famous for rice production in all over the world, but economic indicators are low toward rice contribution in the regional economy. Climatic and physical factors are responsible for rice yield degradation. Suitable land for rice cultivation can be mapped keeping in view these climatic and physical factors. In this research, rice cultivation season was calculated using Moderate Resolution Imaging Spectro-radiometer (MODIS) time series datasets for the complete year 2014. Landsat 8 thermal datasets were obtained for the rice cultivation season and temperature based growth variability maps were generated. The total area under investigation was 13,657 km 2 out of which 931.61 km 2 (6.8%) was found to be least suitable, 3316.69 km 2 (24.2%) was moderately suitable, 6019.63 km 2 (44%) was highly suitable and 3395.28 km 2 (24.85%) was not suitable for rice crop cultivation. Results showed that highly suitable area was characterized by a temperature range between 21 and 32 °C, soil pH level between 5.5 and 7.2, soil type was < 78% clay and the soil was imperfectly drained. We compared land suitability map covering the complete land use with rice cultivated area only and found the results as follows: 592 km 2 (5.9%) rice cultivation was in least suitable, 4385 km 2 (44%) cultivation was in highly suitable, 2210 km 2 (23.2%) cultivation was in moderately suitable and 1674 km 2 (16.8%) cultivation was in not suitable regions. The techniques applied in this research may be used by local farmers to select cropping patterns and land suitability for rice crop.