Featuring image: Oxygen was not always present in Earth’s atmosphere, but stated to accumulate only around 3.5 billion years ago. Pixabay, Public Domain (CC0)
Authors: S. Marchi, N. Drabon, T. Schulz, L. Schaefer, D. Nesvorny, W. F. Bottke, C. Koeberl and T. Lyons
Take a deep breath. Your lungs fill with air and vital oxygen. Not only you, but all higher life depends on oxygen. In the Archean aeon, which lasted from 4 to 2.5 billion years before present, Earth’s atmosphere contained no oxygen. How did oxygen accumulate in the atmosphere? A team of researchers discovered that the evolution of our atmosphere was strongly influenced by impacts of large meteorites when our planet was still young.
Featured Image: Raj Bhagatt P (published with permission from the author)
Castán Broto, V., Sudhira, H. and Unnikrishnan, H. (2021), WALK THE PIPELINE: Urban Infrastructure Landscapes in Bengaluru’s Long Twentieth Century. Int. J. Urban Reg. Res., 45: 696-715. https://doi.org/10.1111/1468-2427.12985
Can a pipeline that runs through an urban landscape weave narratives of water usage through space and time? A beautiful article published in the International Journal of Urban and Regional Research captures some of the stories along the oldest pipeline in Bengaluru, South India. The narratives talk of the urban and rural divide, the patterns of urban sprawl, the pre-colonial water management, and the scarcity faced today.
Before the pipeline, Bengaluru relied on an ancient network of seasonally-replenished tanks, reservoirs and open wells for its agrarian water supply. This network was engineered to harness the natural gradients of Bengaluru’s topography, and to ensure water reached different parts of the city. In 1894, the Chamarajendra waterworks laid down the first modern iron pipeline to source water from the Arkavathi river to Bengaluru’s colonial heart – and history was made. Based on old planning records and an analysis of historic maps, this pipeline today can be traced from the low-level reservoir at the heart of Bengaluru, passing through the neighbourhoods of Malleshwaram, Yeshwanthpur, and Dasarahalli, ending at the Hesaraghatta tank at the northwest corner of the city. Throughout history, the pipeline has affected the lives of people and other urban infrastructure along the way, and continues to do so.
In the 1960s, the Bangalore Water Supply and Sewerage Board (BWSSB) was created to meet the demands of the city. Yet with the ever-expanding urban stretches and the burgeoning population, water scarcity is among the major challenges faced by Bengaluru today. Pipelines from Tarabanahalli, and from Shivanasamudra, along with the old one from Hesaraghatta, transfer water from the rural outskirts to the heart of Bengaluru. In addition, groundwater resources and some water from the Arkavathi river is carried by tankers into the city, to supplement the 6,000 public borewells, and roughly 50,000 residential borewells. Despite water conservation efforts like rainwater harvesting and recycling, the water scarcity in Bengaluru has begun to have ecological and environmental impacts – and the impact will be disproportionately felt by the low-income groups, who can not afford private borewells, nor the cost of long-distance transfers.
A 1914 map of Bengaluru by Baedekar showing some of the old tanks in the heart of the city. In the colonial era, as a cantonment, tanks and wells served much of the city’s water demands. Image: public domain.
The article goes on to reflect on the historical, socio-economic, and political aspects of the neighbourhoods through which the pipeline flows – almost like a travelogue with a bitter note. As the pipeline networks developed, they created a set of conditions for residential and industrial development. Some neighbourhoods benefit directly from the pipeline, whereas some don’t, and over time the pipeline has further marginalized the poorer populations from receiving a good supply of water. These disparities will only get starker in the years to come. Residential overcrowding, land misappropriation, pollution, and increasing demand for industry and residences affect the efficiency of the water network and strain the groundwater resources. As more technological solutions are sought, the local ecologies that sustained these past water systems – such as agricultural patches that helped replenish tanks, the numerous rainwater-filled lakes that have since disappeared due to encroachment, or are severely polluted and littered, have been ignored.
The article underlines a harsh truth – Bengaluru never had enough water. If we are to strategize our water infrastructures again, we need new technological approaches, new resources or to reverse the direction of services from the peri-urban area to the centre of the city and vice versa, with due cognizance of encroachment and violations by existing and future development. The traditional system of tanks and wells needs to be integrated into the broader network of water resources to meet the needs of an ever-expanding urban nexus.
There has been a lot of talk about transportation as of late with America’s “Build Back Better Act”. While these political decisions are partially informed by scientific research around climate change, particularly in the United States (where 30% of greenhouse gas emissions result from transportation by road, rail, and air each year), the negative impacts of transportation infrastructure on the climate and local ecosystems are often lost in political discussions. In a new study in Scientific Reports, Kupka and colleagues discuss the broader impacts of highway maintenance on nearby forest soil ecosystems, finding that roadways themselves can increase carbon dioxide emissions by disrupting local carbon cycles.
Right now in Glasgow, Scotland, representatives of world governments and other parties are currently gathering yet again to negotiate political solutions to climate change at COP26. This is the 26th semi-annual Conference of the Parties on climate change, but the history of our understanding of the problem — and attempts to deal with it — goes back even further than that. Speaking strictly of the science of global warming and its effects, what do we know now that the participants of the first COP did not?
