land use change

The Climate Impact Of Diets | Earth Wise

August 24, 2023 By EarthWise Leave a Comment

The food system is responsible for 70% of the world’s freshwater use and almost 80% of freshwater pollution. About three-quarters of the ice-free land area of the planet has been affected by human use, primarily for agriculture. Land-use change such as deforestation is a major source of biodiversity loss. What we choose to eat has a major effect on how the food system impacts the environment.

A comprehensive study by researchers at several UK universities has found that a plant-based diet yields one-fourth as much greenhouse gases as a diet rich in meat. Vegan diets produce 75% less heat-trapping gas, generate 75% less water pollution, and use 75% less land than meat-rich diets.

Just going to a low-meat diet cuts the environmental cost of a high-meat diet in half. Pescatarian diets perform better than low-meat diets, and vegetarian diets do even a little better than that.

There are a variety of reasons why many people won’t, can’t, or even shouldn’t become vegans. What should be learned from this study is that our dietary choices have a major environmental impact. So, taking actions like cutting down the amount of meat and dairy – which most people can do with relative ease – can be valuable.

There are many choices with respect to where we live, how we get from place to place, where we get our food, and, yes, what food we eat, that impact the environment. We are not all going to do the best possible thing in all these cases, but if we each make some choices that at least help, it can make a big difference.

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Vegan Diets Have One-Fourth the Climate Impact of Meat-Heavy Diets, Study Finds

Photo, posted November 5, 2017, courtesy of Stephanie Kraus via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

North American Birds And Climate Change | Earth Wise

August 10, 2022 By EarthWise Leave a Comment

Most plants and animals live in areas with specific climate conditions, such as rainfall patterns and temperature, that enable them to thrive. Any change in the climate of an area can affect the plants and animals living there, which in turn can impact the composition of the entire ecosystem.

As such, the changing climate poses many challenges to plants and animals. For example, appropriate climatic conditions for many species are changing. As a result, some may even disappear altogether. These problems can be compounded when the climate is changing in tandem with other human-caused stressors, such as land use change.

When there is increasing divergence between suitable climatic conditions for a particular species and its abundance and distribution through time, this is known as climate decoupling.

According to a new study recently published in the journal Nature Ecology & Evolution, some species of North American birds have not fully adjusted their distributions in response to climate change. The areas where these birds live have become more decoupled from their optimal climate conditions. Climate decoupling as a result of ongoing climate change could lead to additional stressors on many bird species and exacerbate bird population declines.

In the study, the research team analyzed data on bird population changes through time from the North American Bird Survey. They found that at least 30 out of 114 species (or 26%) of North American birds have become less well adjusted to their climate over the last 30 years. This means that their distributions and abundances were increasingly decoupled from climate over time.

The researchers also found that the overall trend of climate decoupling shows no signs of slowing down.

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North American birds not fully adjusting to changing climate

Photo, posted July 16, 2016, courtesy of Kelly Azar via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And Forest Loss | Earth Wise

May 23, 2022 By EarthWise Leave a Comment

India is one of the most biodiverse countries in the world. An estimated 47,000 plant species and 89,000 animal species can be found in India, with more than 10% of each thought to be on the list of threatened species.

India is also among the top ten countries in the world in terms of total forest coverage. According to Indian government data, the total forest and tree cover in India is 312,000 square miles, which is 24.62% of the geographical area of the country.

However, forest loss in India has been a problem for many decades driven largely (researchers thought) by land use change. But it turns out that climate change may also have been contributing to forest loss, and its impact is projected to become an even bigger problem in the coming years.

In the first ever national-scale study of the relationship between forest loss and rainfall and temperature trends in India, researchers from the University of Reading in the U.K. found that climate change may have contributed to large declines in forest since the turn of the century.

The study, which was recently published in the journal Global Change Biology, found far greater forest losses were observed where and when the climate was changing most rapidly. Decreases in rainfall had the strongest impact on forest loss.

These findings exacerbate concerns about the already-worrying levels of deforestation in the country, and contradict official reports that have shown relatively small decreases in forest coverage in recent years.

The research team warns that rapid changes to the climate in some regions will require targeted preservation action to reduce the risk to biodiversity in India.

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Indian forest loss ‘worse than feared’ due to climate change

Photo, posted January 20, 2013, courtesy of Dicky Broadhurst / Frontier Official via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Food And Greenhouse Gas Emissions | Earth Wise

December 29, 2021 By EarthWise Leave a Comment

**According to a study published in the journal Nature Food, the world’s food systems are responsible for more than one third of global greenhouse gas emissions caused by human activities.**

‘Eat Local’ is often recommended as a way to minimize the carbon footprint of our diet. But from a climate impact perspective, eating local only has a significant impact if transportation is responsible for a large portion of a food’s final carbon footprint. And in many cases, greenhouse gas emissions related to transportation make up only a small portion of the emissions from food and what we eat is far more important.

There are massive differences in the greenhouse gas emissions of various foods.

For example, producing one pound of beef generates 60 pounds of greenhouse gas emissions. This is more than double the next closest food (lamb), and more than 60 times greater than some plant crops like corn and cassava.

For most foods – especially the largest emitters – greenhouse gas emissions from land use change combined with the emissions from processes at the farm stage account for more than 80% of the environmental footprint. Meanwhile, transportation accounts for less than 10%, and its contribution for the largest emitters is even smaller. For example, transportation accounts for 0.5% of emissions from beef production.

Eating beef or lamb has many times the carbon footprint of most other foods. It matters very little in terms of emissions whether it was grown locally or shipped from another part of the world. It’s not the location that makes the carbon footprint of our dinner large. It’s what is on our plate that matters.

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Food systems account for over one-third of global greenhouse gas emissions

You want to reduce the carbon footprint of your food?

Photo, posted November 7, 2018, courtesy of Preston Keres / USDA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

How To Bend The Curve On Biodiversity Loss | Earth Wise

October 15, 2020 By EarthWise Leave a Comment

Biodiversity has been declining at an alarming rate in recent years as a result of human activities, including land use changes, pollution, and climate change. According to a 2019 UN report, one million species – out of an estimated eight million – are threatened with extinction. Many scientists warn we are in the middle of the sixth mass extinction event in Earth’s history. Previous mass extinction events wiped out up to 95% of all species and took ecosystems millions of years to recover.

Fortunately, new research indicates that it might not be too late to bend the curve on biodiversity loss. According to the report, which was recently published in the journal Nature, more ambitious conservation measures are needed in order to preserve biodiversity. In addition, more efficient food production and healthier and less wasteful consumption and trade are needed to bend the curve.

If these measures are undertaken with unprecedented ambition and coordination, the research team says the efforts will provide an opportunity to reverse biodiversity loss by 2050.

But even under the best case scenario, ongoing land conversion will lead to further biodiversity losses before the curve starts to bend. In fact, at least one third of projected losses in the coming years are unlikely to be avoided under any scenario. Biodiversity losses were projected to be highest in the regions richest in biodiversity, including South Asia, Southeast Asia, Sub-Saharan Africa, the Caribbean, and Latin America.

The study, which was led by the International Institute for Applied Systems Analysis in Austria, makes it clear that urgent action is needed this decade in order to have any chance of bending the curve.

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Curbing land clearing for food production is vital to reverse biodiversity declines

Photo, posted November 1, 2017, courtesy of Rod Waddington via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Land Use Change And Flooding | Earth Wise

September 30, 2020 By EarthWise Leave a Comment

Land use change refers to the conversion of a piece of land’s use by humans from one purpose to another. Land use change is commonly associated with biodiversity loss and increased greenhouse gas emissions. But how does land use change impact water cycles?

According to researchers from the University of Göttingen in Germany, IPB University, and BMKG (both in Indonesia), the expansion of monocultures, such as rubber and oil palm plantations, leads to more frequent and more severe flooding. The researchers explain the increase in flooding “with a complex interplay of ecohydrological and social processes, including soil degradation in monocultures, the expansion of oil palm plantations into wetlands, and the construction of flood protection dams.”

For the study, which was recently published in the journal Ecology & Society, the research team interviewed nearly 100 Indonesian farmers, villagers, and decision-makers in Sumatra. The team supplemented its research with data on precipitation, river and groundwater levels, soil properties, and regional mapping.

During large-scale land use change – like plantation expansions – newly-compacted soil causes rainwater to runoff as opposed to being absorbed. As more plantations are established in floodplains, the owners try to control flooding on their land by building barriers. But these dams often lead to increased flooding on neighboring lands. This understandably triggers social tensions between other farmers and plantation owners.

In order to reduce the negative impact of land use change on the water cycle, the research team suggests soil protection and improved planning – especially in floodplains – would be a good place to start.

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Land use change leads to increased flooding in Indonesia

Photo, posted October 8, 2018, courtesy of Artem Beliaikin via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.