Land use changes and its link to climate change Flashcards
Economic costs of GHG abatement
How working out the abatement costs reduces overall emissions
Agricultural land on Earth’s surface
Agricultural lands occupy 37% of the earth’s land surface. Agriculture accounts for 52 and 84% of global anthropogenic methane and nitrous oxide emissions.
Uk climate change committee recommendations of reducing emissions cost effectively from agriculture - 9 MtCO2e from measures that decrease N20 emissions from crops and soils including
reducing fertilizer application where it is applied in excess
matching the timing of application with the time when the crop will make most use of it
using organic rather than synthetic fertilizer when possible
improving drainage of land
selectively breeding plants that need less fertiliser.
Emissions intensity for different food products
Around 17kgCO2e/kg product for Sheep Meet
16kgCO2e/kg product for Beef
11kgCO2e/kg product for Milk
Williams et al (2006)
Global land use change
Expansion of agriculture at expense of forests and natural grasslands
Land use change and carbon cycle impact
US land use change in past 50 years has led to accumulation of carbon
Mainly due to reafforestation on previous agricultural land
Forestry impact on carbon to the atmosphere
Forestry, despite locking up carbon above ground, is a net source of carbon to the atmosphere because of loss of carbon from draining peatland and from afforestation of previous mature woodland
Socieities land use regimes over time
from presettlement natural vegetation to frontier clearing, then to subsistence agriculture and small-scale farms, and finally to intensive agriculture, urban areas, and protected recreational lands
Market solutions to carbon land use dilemmas
If the atmosphere is a global pubic good, then it is overused because it is undervalued. Market solution is to create rights and hence markets in carbon
UNFCCC created carbon markets through e.g. Clean Development Mechanism and REDD (Reduced Emissions from Deforestation and Degradation)
Land use change contribution to global Co2 emissions
Land use change, largely from deforestation , contributes up to 20—25% of global Co2 emissions
Incentives needed
Incentives needed to improve land management and reduce deforestation/degradation
A ton of CO2 sequestered by forests has an economic value defined by the “market”
Carbon sequestration
Actively managing land or forest ecosystems in order to increase biomass levels above present conditions e.g. reforestation, sustainable forest management etc
REDD
Avoided Deforestation and/or reducing emissions from deforestation and degradation (REDD): Avoiding emissions from land use change by protecting and conserving forest ecosystems at high risk of deforestation and degradation.
Forest Carbon projects and local livelihoods
Resource diversification and forest conservation
Increased collective and household income
Investment in infrastructure
Improved organizational skills around forest management
Ecological impacts
Exclusion of informal tenants.