Land use changes and its link to climate change

Question 1

Economic costs of GHG abatement

Answer 1

Question 2

How working out the abatement costs reduces overall emissions

Answer 2

Question 3

Agricultural land on Earth’s surface

Answer 3

Agricultural lands occupy 37% of the earth’s land surface. Agriculture accounts for 52 and 84% of global anthropogenic methane and nitrous oxide emissions.

Question 4

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

Answer 4

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.

Question 5

Emissions intensity for different food products

Answer 5

Around 17kgCO2e/kg product for Sheep Meet

16kgCO2e/kg product for Beef

11kgCO2e/kg product for Milk

Williams et al (2006)

Question 6

Global land use change

Answer 6

Expansion of agriculture at expense of forests and natural grasslands

Question 7

Land use change and carbon cycle impact

Answer 7

US land use change in past 50 years has led to accumulation of carbon

Mainly due to reafforestation on previous agricultural land

Question 8

Forestry impact on carbon to the atmosphere

Answer 8

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

Question 9

Socieities land use regimes over time

Answer 9

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

Question 10

Market solutions to carbon land use dilemmas

Answer 10

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)

Question 11

Land use change contribution to global Co2 emissions

Answer 11

Land use change, largely from deforestation , contributes up to 20—25% of global Co2 emissions

Question 12

Incentives needed

Answer 12

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”

Question 13

Carbon sequestration

Answer 13

Actively managing land or forest ecosystems in order to increase biomass levels above present conditions e.g. reforestation, sustainable forest management etc

Question 14

REDD

Answer 14

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.

Question 15

Forest Carbon projects and local livelihoods

Answer 15

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.

Question 16

Accounting carbon offsets or emissions reduced from avoiding deforestation

Question 17

Managing land or forest ecosystems to increase biomass

Answer 17

Requires understanding of carbon flux across different carbon pools and throughout time
Requires rigorous methods for offset accounting

Question 18

Ruminant GHG production

Answer 18

GHG emission from ruminant meat production are significant. Reductions in ruminant numbers could make a substantial contribution to climate change mitigation goals and yield important social and environmental co-benfits

Ripple et al (2014)

Question 19

Non Co2 GHG contribution

Answer 19

At present non-CO2 GHGs contribute about a third of total anthropogenic CO2 equivalent emissions and 35-45% of climate forcing.

Ripple et al, 2014

Question 20

Methane contribution

Answer 20

Methane is the most abundant non-CO2 GHG because it had a much shorter atmospheric lifetime than CO2 it holds the potential for more rapid reductions in radiative forcing than would be possible by controlling emissions of Co2 alone.

Ripple et al, 2014

Question 21

Livestock sector emissions

Answer 21

Worldwide, the livestock sector is responsible for approximately 14.5% of all anthropogenic GHG emissions.

Approximately 44% of livestock sector emissions are in the form of Ch4 from enteric fermentation, manure and rice feed, with the remaining portions almost equally shared between CO2 from land-use change and fossil fuel use, and nitrous oxide

Ripple et al, 2014

Question 22

Ruminant agriculture negatives

Answer 22

Ruminant agriculture can have negative impacts on water quality, and availability, hydrology and riparian ecosystems.

Ripple et al, 2014

Question 23

Ruminant production negatives

Answer 23

Ruminant production can erode biodiversity through a wide range of processes such as forest loss and degradation, land use intensification, exotic plant invasions, soil erosion etc.

Ripple et al, 2014

Question 24

Rates of meat consumpion in developed countries

Answer 24

In developed countries, high levels of meat consumption rates are strongly correlated with rates of disease such as obsesity, diabetes, some common cancers and heart disease

Ripple et al, 2014

Question 25

Global expansion of croplands

Answer 25

One estimate holds that the global expansion of croplands since 1850 has converted some 6 million km2 of forests/woodlands and 4.7 millionkm2 of savannas/grasslands Lambin et al (2001)

Question 26

High rates of deforestation are linked

Answer 26

High rates of deforestation within a country are most commonly linked to population growth and poverty, shifting cultivation in large tracts of forests. The misconception that follows is that most tropical deforestation occurs by the “push” of population growth and poverty to invade, slash and burn the forest along the roads Lambin et al (2011)

Question 27

Rapidly developing land scarcity may trigger

Answer 27

Rapidly developing land scarcity may trigger increase in cropping frequency unmatched by appropriate changed in inputs or management, resulting in a “stressed” system, abandoned “landesque” capital and land degradation Ripple et al, 2014

Question 28

Forest gross photosynthesis

Answer 28

Every year forest gross photosynthesis cycles approximately one twelfth of the atmospheric stock of CO2, accounting for 50% of terrestrial photosynthesis. Malhi et al (2002)

Question 29

Maximum carbon sequestered

Answer 29

In the course of the whole century, however, even the maximum amount of carbon that could be sequestered will be dwarfed the magnitude of fossil fuel emissions Malhi et al (2002)

Question 30

Worldwide changes are being driven by

Answer 30

Worldwide changes to forests, farmlands, waterways, and air are being driven by the need to provide food, fiber, water and shelter to more than 6 billion people Foley et al (2005)

Question 31

Anthropogenic Co2 from land use

Answer 31

Since 1850, roughly 35% of anthropogenic Co2 emissions resulted directly from land use Foley et al (2005)

Question 32

Anthropogenic nutrient input

Answer 32

Anthropogenic nutrient inputs to the biosphere from fertilizers and atmospheric pollutants now exceed natural sources and have widespread effects on water quality and coastal and freshwater ecosystems Malhi et al (2002)

Question 33

Land use decline in biodiversity

Answer 33

Land use has also caused declines in biodiversity through the loss, modification, and fragmentation of habitats, degredation of soil and water, and overxploitation of native species. Foley et al (2005)

Question 34

One of the primary causes of environmental change

Answer 34

One of the primary causes of global environmental change is tropical deforestation Foley et al (2005)

Question 35

Reasons for tropical deforestation - public and individual level

Answer 35

at the underlying level public and individual decisions largely respond to changing, national-to global-scale economic opportunities and/or policies, as mediated by local scale institutional factors, and that, at the proximate level, regionally distinct modes of agricultural expansion, wood extraction, and infrastructure extension prevail in causing deforestation Geist and Lambin (2002)