soil and climate change

Erosion.jpg
cracked earth 2.jpg
Dry earth.jpg

Soil health and climate change are intrinsically linked. On the one hand, soils are the second largest carbon sink after our oceans, storing 3x more carbon than is found in the atmosphere. On the other hand, rising temperatures and changing precipitation patterns can lead to soil erosion and fertility loss and a decline in soil’s ability to carry out basic ecosystem services.

With climate change a political and scientific priority, scrutiny is growing of soil’s potential role in capturing and storing carbon. This year both the UK Climate Change Committee and the Institute for European Environmental Policy included carbon sequestration among the critical levers required for agriculture to reach net-zero and sharply decrease its emissions by 2050.

But how to define and accurately account for soil’s contribution? The UK Is a signatory to the 2015 4 per 1000 initiative, which is built on the premise that an annual growth rate of 0.4% in  soil carbon stocks would significantly reduce CO2 concentration in the atmosphere related to human activities.

The arithmetic behind this claim is disputed, however. Scientists led by Rothamsted Research in the UK, whilst welcoming 4/1000 in principle, argue that the goal is only attainable in certain geographies and circumstances and warn against it being relied upon by policy makers as they look to achieve their carbon reduction goals.

There are a number of factors to consider. For a start, when it comes to carbon storage not all soils are equal. The most carbon-rich soils are peatlands, mostly found in northern Europe, the UK and Ireland, while grassland soils also store a lot of carbon per hectare. Then there is the impact of different farming systems, nitrogen availability, crop selection and cropping practices; and, finally, the rate at which carbon is captured, for how long and how it is accounted for once released.

The challenge of estimating potential gain in carbon is made more acute with the increasing inclusion of soil in carbon emissions trading schemes and carbon taxes. In the US and Canada greenhouse gas reduction credits are being issued to farmers who adopt conservation practices, and there is potential for these schemes to be expanded to offset emissions elsewhere. In the UK upstream soil management practises can go a long way to reducing water contamination, so cutting the energy and therefore the carbon costs for the water companies charged with cleaning it.

 At the SSA we look to monitor, analyse and understand the evolving political, scientific and economic framework as it relates to soil carbon, and specifically:

o   Channel the most relevant and up-to-date research relating to soil carbon to policy makers and other stakeholders

o   Engage the private sector and provide them with a platform to showcase their work to incentivise land management practises that sequester carbon, including carbon trading mechanisms

o   Call for government to invest in soil carbon research and modelling to identify the soil types and farming practices that provide the greatest opportunity for carbon gain

o   Make the case for sustainable farming practices such as agroforestry and conservation agriculture

the latest research on soil & climate change:

Global Assessment on Biodiversity & Ecosystems   IPBES  6 May 2019    23% of our agricultural lands are less productive than 5 years ago   . In refreshingly bold terms, the report comments on the role agricultural subsidies play in catalyzing soil health degradation and biodiversity loss… Chemicals and synthetic fertilizers promise short-term boosts in crop yields, but the overapplication and reliance on chemicals and synthetic fertilizers on commodity farms create soil conditions that are inhospitable for the soil microbiome.

Global Assessment on Biodiversity & Ecosystems

IPBES

6 May 2019

23% of our agricultural lands are less productive than 5 years ago. In refreshingly bold terms, the report comments on the role agricultural subsidies play in catalyzing soil health degradation and biodiversity loss… Chemicals and synthetic fertilizers promise short-term boosts in crop yields, but the overapplication and reliance on chemicals and synthetic fertilizers on commodity farms create soil conditions that are inhospitable for the soil microbiome.

Net Zero: The UK’s contribution to stopping global warming   Climate Change Committee  2 May 2019   The work confirmed the view that harvesting and using biomass can play an important role in reducing emissions - provided that it is done as part of a system of sustainable land use. As a minimum this requires managing the carbon stocks in plants and soils so that they increase over time. There is scope to increase terrestrial carbon stocks and levels of sustainable harvested biomass both globally and in the UK. But stronger governance is needed to ensure this happens in practice.

Net Zero: The UK’s contribution to stopping global warming

Climate Change Committee

2 May 2019

The work confirmed the view that harvesting and using biomass can play an important role in reducing emissions - provided that it is done as part of a system of sustainable land use. As a minimum this requires managing the carbon stocks in plants and soils so that they increase over time. There is scope to increase terrestrial carbon stocks and levels of sustainable harvested biomass both globally and in the UK. But stronger governance is needed to ensure this happens in practice.

The impact of long-term organic farming on soil-derived greenhouse gas emissions   Nature  8 Feb 2019   Agricultural practices contribute considerably to emissions of greenhouse gases. We compared two organic farming systems with two non-organic systems. We observed a 40.2% reduction of N2O emissions per hectare for organic compared to non-organic systems. In contrast to current knowledge, yield-scaled cumulated N2O emissions under silage maize were similar between both systems.

The impact of long-term organic farming on soil-derived greenhouse gas emissions

Nature

8 Feb 2019

Agricultural practices contribute considerably to emissions of greenhouse gases. We compared two organic farming systems with two non-organic systems. We observed a 40.2% reduction of N2O emissions per hectare for organic compared to non-organic systems. In contrast to current knowledge, yield-scaled cumulated N2O emissions under silage maize were similar between both systems.

 
Facing up to the Age of Environmental Breakdown    IPPR  February 2019   The window of opportunity to avoid catastrophic outcomes globally is rapidly closing. Disregard of environ’tl considerations in most areas of policy has been a catastrophic mistake.

Facing up to the Age of Environmental Breakdown

IPPR

February 2019

The window of opportunity to avoid catastrophic outcomes globally is rapidly closing. Disregard of environ’tl considerations in most areas of policy has been a catastrophic mistake.

The Business Case for Investing in Soil Health    WBCSD  5 December 2018   Global soils contain 2-3x more carbon than the atmosphere: by working with nature & improving soil health, carbon sequestration can reduce emissions & withstand some of the unavoidable effects of climate change.

The Business Case for Investing in Soil Health

WBCSD

5 December 2018

Global soils contain 2-3x more carbon than the atmosphere: by working with nature & improving soil health, carbon sequestration can reduce emissions & withstand some of the unavoidable effects of climate change.

POSTnote: Trends in Agriculture    Parliamentary Office of Science & Technology  November 2018   Key drivers of global agricultural trends & the challenge of safeguarding both food production and environment value in a changing world.

POSTnote: Trends in Agriculture

Parliamentary Office of Science & Technology

November 2018

Key drivers of global agricultural trends & the challenge of safeguarding both food production and environment value in a changing world.

Global Warming of 1.5 ° : Summary for Policymakers    Intergovernmental Panel on Climate Change  6 October 2018   Global warming is likely to reach 1.5° 2030 - 2052 if it continues to increase at the current rate.

Global Warming of 1.5°: Summary for Policymakers

Intergovernmental Panel on Climate Change

6 October 2018

Global warming is likely to reach 1.5° 2030 - 2052 if it continues to increase at the current rate.

 
Opportunities for Soil Sustainability in Europe    European Academies Science Advisory Council  September 2018   Soil biodiversity & its contribution to above-ground diversity, modern farming, plant and human health (&) interactions between soil & climate change.

Opportunities for Soil Sustainability in Europe

European Academies Science Advisory Council

September 2018

Soil biodiversity & its contribution to above-ground diversity, modern farming, plant and human health (&) interactions between soil & climate change.

Greenhouse Gas Removal    The Royal Society / Royal Academy of Engineering  September 2018   Draws on a breadth of expertise to identify the range of available greenhouse gas removal methods, the factors that will affect their use & how they may be deployed together to meet climate targets.

Greenhouse Gas Removal

The Royal Society / Royal Academy of Engineering

September 2018

Draws on a breadth of expertise to identify the range of available greenhouse gas removal methods, the factors that will affect their use & how they may be deployed together to meet climate targets.

Soils & Climate: From hidden depths to centre stage?    Hoffman Centre for Sustainable Resource Economy  March 2018   Knowledge gaps and priorities to accelerate soil organic carbon storage & sequestration.

Soils & Climate: From hidden depths to centre stage?

Hoffman Centre for Sustainable Resource Economy

March 2018

Knowledge gaps and priorities to accelerate soil organic carbon storage & sequestration.

Soil and its Sustainability    Nature  2015   A collection of articles that explore soil in its manifold roles in shaping environment & society. Make-up & management of soils, and their influence on human health and extreme poverty, are some of the topics investigated.

Soil and its Sustainability

Nature

2015

A collection of articles that explore soil in its manifold roles in shaping environment & society. Make-up & management of soils, and their influence on human health and extreme poverty, are some of the topics investigated.

 
Lowland peatland systems in England & Wales – Evaluating greenhouse gas fluxes and carbon balances    CEH  2017   Lowland peatlands are one of the UK’s most carbon-rich ecosystems & are now amongst the largest sources of GHG emissions.

Lowland peatland systems in England & Wales – Evaluating greenhouse gas fluxes and carbon balances

CEH

2017

Lowland peatlands are one of the UK’s most carbon-rich ecosystems & are now amongst the largest sources of GHG emissions.

Natural Climate Solutions    Proceedings of the National Academy of Sciences of the USA  October 2017   Natural climate solutions can provide 37% of CO2 mitigation needed through 2030 for a >66% chance of holding warming to below 2 °  C.

Natural Climate Solutions

Proceedings of the National Academy of Sciences of the USA

October 2017

Natural climate solutions can provide 37% of CO2 mitigation needed through 2030 for a >66% chance of holding warming to below 2° C.

Meeting Carbon Budgets: Closing the policy gap    Committee on Climate Change  June 2017   The UK urgently needs new policies to cut emissions. Climate change will not wait while other priorities are addressed.

Meeting Carbon Budgets: Closing the policy gap

Committee on Climate Change

June 2017

The UK urgently needs new policies to cut emissions. Climate change will not wait while other priorities are addressed.

Aligning Agriculture & Climate Policy    Nature  28 April 2017   The 4‰ initiative to sequester carbon in soils has the potential to connect sustainable development goals, enhance food security and mitigate climate change by utilizing waste organic residues.

Aligning Agriculture & Climate Policy

Nature

28 April 2017

The 4‰ initiative to sequester carbon in soils has the potential to connect sustainable development goals, enhance food security and mitigate climate change by utilizing waste organic residues.