Background
The rate of build-up of carbon dioxide (CO2) in the atmosphere can be reduced by taking advantage of the fact that atmospheric CO2 can accumulate as carbon in vegetation and soils in terrestrial ecosystems. Under the United Nations Framework Convention on Climate Change any process, activity or mechanism which removes a greenhouse gas (GHG) from the atmosphere is referred to as a "sink". Human activities impact terrestrial sinks, through land use, land-use change and forestry (LULUCF), consequently, the exchange of CO2 (carbon cycle) between the terrestrial biosphere and the atmosphere is altered.
The Intergovernmental Panel on Climate Change (IPCC) 6th assessment report finds that the “Agriculture, Forestry and Other Land Use (AFOLU)” sector on average, accounted for 13-21% of global total anthropogenic GHG emissions in the period 2010-2019. Estimated anthropogenic net CO2 emissions from AFOLU (based on bookkeeping models) result in a net source of +5.9±4.1 GtCO2eq/yr between 2010 and 2019 with an unclear trend. Land use change drivers net AFOLU CO2 emission fluxes, with deforestation being responsible for 45% of total AFOLU emissions. In addition to being a net carbon sink and source of GHG emissions, land plays an important role in climate through albedo effects, evapotranspiration, and aerosol loading through emissions of volatile organic compounds.
The IPCC report finds that the LULUCF sector offers significant near-term mitigation potential while providing food, wood and other renewable resources as well as biodiversity conservation. Mitigation measures in forests and other natural ecosystems provide the largest share of the LULUCF mitigation potential between 2020 and 2050. Among various LULUCF activities, reducing deforestation has the largest potential to reduce anthropogenic GHG emissions, followed by carbon sequestration in agriculture and ecosystem restoration including afforestation and reforestation (See Figure SPM.7 in the IPCC WGIII report).
Other terrestrial systems also play an important role. Most of the carbon stocks of croplands and grasslands are found in the below-ground plant organic matter and soil. Consequently, improved and sustainable crop and livestock management, and soil carbon sequestration in agriculture, the latter includes soil carbon management in croplands and grasslands, agroforestry and biochar, can contribute to the reduction of 1.8–4.1 GtCO2eq/yr, according to the IPCC.
Mitigation activities in the LULUCF sector can have multiple synergies with the Sustainable Development Goals (SDGs), such as enhancing biodiversity and ecosystem functions, employment and local livelihood. In another light, the IPCC report recognizes that some activities, such as deployment of afforestation of naturally unforested land, can compound climate-related risks to biodiversity, water and food security, and livelihoods, especially if not implemented with due consideration to the local conditions including current use of the land. Such risks can best be managed if LULUCF mitigation is pursued in response to the needs and perspectives of multiple stakeholders to achieve outcomes that maximise synergies while limiting trade-offs.
However, the main challenges of LULUCF activities are their potential reversibility and non-permanence of carbon stocks. The storage of CO2 through vegetation and soil management can be reversed by human activities, natural disturbances or a combination of the two, and it is also prone to climate change impacts. Such severe impacts including wildfires, mass mortality of trees and weakening natural land carbon sinks, are already observed and are projected to increase with every additional increment of global warming. Concerted, rapid and sustained actions that limit global warming to close to 1.5°C would substantially reduce projected losses and damages related to climate change in ecosystems, according to the IPCC.
Topics relating to LULUCF
LULUCF sector under the Convention
LULUCF activities under the Kyoto Protocol
LULUCF activities under the Paris Agreement
Cooperation with other organizations
The emergence of and continuing significance of issues related to LULUCF has stimulated cooperation with many organizations and institutions with forestry and agriculture experiences.
The Collaborative Partnership on Forests (CPF). The CPF is s an innovative interagency partnership on forests comprising 14 international organizations, institutions and secretariats that have substantial programmes on forests. The mission of the Collaborative Partnership on Forests is to promote sustainable management of all types of forests and to strengthen long-term political commitment to this end.
The Food and Agriculture Organization of the United Nations (FAO). The Forestry Department of FAO has considerable experience in, among others, building capacity in developing countries and in assessing the global status of forests. Its work includes the publication of the Global Forest Resources Assessment as a contribution to knowledge on the state of the world's forests.
The Intergovernmental Panel on Climate Change (IPCC). The IPCC is an independent body funded under the auspices of the World Meteorological Organization and the United Nations Environment Programme. The IPCC authors assessment reports, which are widely recognized as the most credible sources of information on climate change, and also carries out important work on methodologies for estimating and reporting GHG emissions. As part of its work related to LULUCF, the IPCC is exploring options to address the discrepancy in net CO2 fluxes from land between global bookkeeping models and the aggregate global net emissions reported in national GHG inventories. For more information, see the recent IPCC Expert Meeting on Reconciling Land Use Emissions.
The United Nations Forum on Forests (UNFF). The UNFF is an intergovernmental process with the objective of promoting the management, conservation and sustainable development of all types of forests. It allows forest policy dialogue facilitated by the Intergovernmental Panel on Forests (IPF) and the Intergovernmental Forum on Forests (IFF).
