The Influence of the Pacific Decadal Oscillation on Annual Floods in the Rivers of Western Canada

We analyzed annual peak flow series from 127 naturally flowing or naturalized streamflow gauges across western Canada to examine the impact of the Pacific Decadal Oscillation (PDO) on annual flood risk, which has been previously unexamined in detail. Using Spearman's rank correlation ρ and permutation tests on quantile‐quantile plots, we show that higher magnitude floods are more likely during the negative phase of the PDO than during the positive phase (shown at 38% of the stations by Spearman's rank correlations and at 51% of the stations according to the permutation tests). Flood frequency analysis (FFA) stratified according to PDO phase suggests that higher magnitude floods may also occur more frequently during the negative PDO phase than during the positive phase. Our results hold throughout much of this region, with the upper Fraser River Basin, the Columbia River Basin, and the North Saskatchewan River Basin particularly subject to this effect. Our results add to other researchers' work questioning the wholesale validity of the key assumption in FFA that the annual peak flow series at a site is independently and identically distributed. Hence, knowledge of large‐scale climate state should be considered prior to the design and construction of infrastructure.     

Hydrogen Peroxide and Ultraviolet Irradiations in Water Treatment

Trihalomethanes (THMs) the by-products of chlorination in water treatment are recognised as a threat to public health due to their carcinogenicity. The photodegradation of THMs using hydrogen peroxide has been found to give increased removal efficiency and the outcome of the study may find, its application in designing a unit process for water treatment. Batch experiments were carried out using UV lamp of 83 W and 40% w/w Hydrogen peroxide (H₂O₂) in test waters between 2.5–10 pH range of chloroform, bromodichloromethane, dibromochloromethane and bromoform at 50–200 μg L⁻¹ initial concentration. 92–100% removal of chloroform, bromodichloromethane, dibromochloromethane and bromoform were found with 0.1% of H₂O₂ and 90 min of UV exposure.     

Biochemical changes in plant leaves as a biomarker of pollution due to anthropogenic activity

The air pollution due to anthropogenic activities seriously affected human life, vegetation, and heritage as well. The vegetation cover in and around the city mitigates the air pollution by acting as a sink for pollution. An attempt was made to evaluate biochemical changes occurred in four selected plant species, namely Azadirachta indica, Mangifera indica, Delonix regia, and Cassia fistula of residential, commercial, and industrial areas of Nagpur city in India. It was observed that the correlated values of air pollutants and plant leaves characteristics alter foliar biochemical features (i.e., chlorophyll and ascorbic acid content, pH and relative water content) of plants due to air pollution. The changes in air pollution tolerance index of plants was also estimated which revealed that these plants can be used as a biomarker of air pollution.     

Community action planning in East Delhi: a participatory approach to build urban disaster resilience

The paper addresses disaster risk of an urban community in a mega city, which experiences high risk to natural hazards. The Community Action Planning (CAP) tool is used in this case. It has been developed from five resilience dimensions (physical, social, economic, institutional, and natural), 25 parameters and 75 actions. A detailed CAP structured questionnaire survey was conducted with 89 Residential and Welfare Associations (RWAs) in East Delhi, India situated in three types of settlements: planned Delhi Development Authority (DDA) housing and societies, colonies, and urban villages. The result identifies and prioritizes 32 actions as important for all three settlements. The result shows both consistent and inconsistent responses from RWAs. To give some examples, parameter S3 is “tasks to reduce number of people suffer from water borne diseases after a disaster”. In response to this parameter, approximately 80% of total respondents prioritized action (A1), “promoting people to take preventive measures after a disaster”. It shows consistent response from all three settlements. However, parameter S5 is “tasks to improve the awareness and knowledge about threat and impact of disasters”. Approximately 40% of total respondents prioritized A1, “organizing training program for awareness and knowledge building”. This action was prioritized in planned DDA housing and societies (56%) as well as in colonies (52%). However, none of the respondents from urban villages prioritized this action. These responses show inconsistency in response to specific action. In addition, the study shows the potential impact of CAP process for other communities in cities that are experiencing disaster risks and impact of climate change.     

A spore-based miniaturized novel assay for rapid aflatoxin detection in milk

Environmental Chemistry Letters - Aflatoxin M1 contamination in milk and dairy products is a major issue worldwide. Aflatoxin is a carcinogen that enters into the milk through animals feed. Here,...     

Riverbank stabilization based on the modulation of the near bank turbulence scales

Environment, Development and Sustainability - Sundarban area of the lower Gangetic plain experiences embankment failure almost every year due to the formation of toe undercuts. Waves generated due...     

Modelling urban heat island (UHI) and thermal field variation and their relationship with land use indices over Delhi and Mumbai metro cities

Environment, Development and Sustainability - According to the World Urbanization Prospects of United Nations, the global urban population has increased rapidly over past few decades, reaching...     

Report: Medical students for monitoring biomedical waste segregation practices--why and how? Experience from a medical college

The cornerstone for an effective biomedical waste (BMW) management is appropriate waste segregation. Improper waste segregation practices can have an adverse impact on public health and increase the cost of treatment. Deficiencies in waste segregation practices can be corrected by continuous monitoring and education. Manpower for monitoring waste segregation in a large teaching hospital is scanty. We utilized the undergraduate medical students as monitors and studied the impact on waste segregation practices. A prospective observational study was carried out from August 2004 to January 2005. For monitoring waste segregation, the different areas of the hospital were divided amongst the II M.B.B.S students. They were provided with an observation sheet wherein the status of waste segregation and overall hygiene was recorded on a scale of 1-5. The impact of this programme was then analysed over the study period. The results indicated that a statistically significant improvement in waste segregation practices occurred in all areas. Thus, a large hospital with a medical college can identify students or a similar group for monitoring waste segregation or other aspects of biomedical waste management. This will improve their understanding of good practice in BMW management in future.     

Aerobic granulation of pure bacterial strain Bacillus thuringiensis

The objective of this study is to cultivate aerobic granules by pure bacterial strain, Bacillus thuringiensis, in a sequencing batch reactor. Stable granules sized 2.0–2.2 mm were formed in the reactor after a five-week cultivation. These granules exhibited excellent settling attributes, and degraded phenol at rates of 1.49 and 1.19 g phenol/(g VSS?d) at 250 and 1500 mg/L of phenol concentration, respectively. Confocal laser scanning microscopic test results show that Bacillus thuringiensis was distributed over the initial small aggregates, and the outer edge of the granule was away from the core regime in the following stage.