agricultural waste

Oxygen Loss In Lakes | Earth Wise

January 13, 2023 By EarthWise Leave a Comment

Researchers from Cornell University and Rensselaer Polytechnic Institute have found that the continual warming in the world over the past 25 years has been reducing the amount of oxygen in many lakes.

Data from more than 400 lakes – mostly in the United States – shows that lakes with dissolved oxygen losses strongly outnumber those with gains. Overall, the researchers found that the amount of low oxygen water is increasing by 0.9% to 1.7% per decade on average and the volume of lake water lacking oxygen has increased by more than 50% from 25 years ago.

In the summer, lake surfaces may be about 70 degrees while the lake bottom may be about 40 degrees. The colder water is denser than the warmer water which causes resistance to the layers mixing. It is akin to having oil and vinegar in a cruet. This is known as stratification. The result is that oxygen from the atmosphere is prevented from replenishing dissolved oxygen in deep waters. This is a normal seasonal phenomenon.

However, with winter ending sooner than it used to, seasonal stratification is starting earlier and ending later. As warming continues, it is likely that there will be an increasing number of oxygen-depleted lakes in the future.

Oxygen deprivation in water can lead to hypoxia (low oxygen) and even anoxia (no oxygen), which have negative consequences for fish and other species. Reducing oxygen in lake water can lead to buildup of methane. Nutrients from agricultural runoff, released from unsettled lake sediment, increase the likelihood of harmful algal blooms.

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Warming climate prompts harmful oxygen loss in lakes

Photo, posted June 23, 2010, courtesy of Alexander Acker via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Car Parts From Agricultural Waste

January 11, 2019 By EarthWise Leave a Comment

A new bio-composite material made from date palm fiber biomass could be used to produce sustainable, lightweight and low-cost parts for the automobile and marine industries.

A team of researchers from the UK has developed a date palm fiber polycaprolactone composite that is completely biodegradable, renewable,sustainable and recyclable, in contrast to synthetic composite materials reinforced by glass and carbon fibers. The team tested the mechanical properties of the material and found that it achieved better low-velocity impact resistance than traditional man-made composites.

The idea would be to use the material in non-structural auto parts such as car bumpers and door linings. The result would be to reduce the weight of vehicles, contributing to less fuel consumption and lower emissions. The new material can be produced using less energy than glass and carbon fibers and is biodegradable and therefore easier to recycle.

Date palm fibers are one of the most available natural fibers in many parts of the world. The trees produce a large quantity of agricultural waste, which is mostly burned or land-filled,causing serious environmental problems.

Convincing industry to use a new class of materials such as natural-fiber reinforced composites is challenging. First it is necessary to obtain consistent,reliable properties from the material. Then the industries need to work closely with the developers to test the materials and convince themselves of the viability of using them. The team, led by researchers at the University of Portsmouth, has been working with industry to test the viability of parts made from a variety of other sustainable materials as well including flax, hemp, and jute. Someday, our cars may have bumpers made from agricultural waste.

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Agricultural waste drives us closer to greener transport

Photo, posted October 27, 2017, courtesy of David Stanley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Pulling Carbon Out Of The Air

January 20, 2016 By WAMC WEB

The world is increasingly united in the desire to reduce carbon emissions into the atmosphere. There is much emphasis on reducing and someday eliminating our use of fossil fuels, which is the main culprit in the situation we find ourselves in today. More and more we are embracing the use of renewable energy sources to produce electricity and we are starting to slowly move away from internal combustion engines to power our cars.