INDG 401 Lecture Notes - Lecture 14: Soil Organic Matter, World Food Summit, Sustainable Development Goals
9 Jun 2018
School
Department
Course
Professor
Lecture 2: Hugo Melgar-Quinonez
Current perspectives on global food security: the challenge towards the sustainable development goal #2
• Food security definition (complex)
o All people, at all times
o Physical and economic access
o To sufficient, safe and nutritious (micro and macro nutrients) food
o Dietary needs (to meet these needs) and preferences (food memory)
o Active and healthy life
o FAO: Rome Declaration on World Food Security, World Food Summit 1996
o Economist say the financial access; nutritionists say it should be healthy; health experts say also
a healthy and active life
• Food production Is not our problem, food waste is a major problem
o We are wasting between 30-50% of the food in the developing countries (due to storage, pests,
transportation etc.)
o In developed countries we waste 25-30%
• Food pillars
• Food sovereignty (take a look at the term)
• Right to adequate food
o Food is a human right
o International Covenant on Economic, Social, and Cultural Rights ICE“CR: the ight of everyone
to adeuate food ad the fudaetal ight to e fee fo huge
▪ Regular, permanent and unrestricted access
▪ Quantitatively and qualitatively adequate food
▪ Corresponding to cultural traditions
o Ratified by over 150 countries
o Legally binding: obligatory for states
• Physical environment (climate
o Chart of the powerpoint
o An environment with different layers: physical, social and political environments
• Food security measurement methods
o FAO method – food balance sheets
o Household income and expenditure surveys
o Adequacy of dietary intake
▪ Are people eating the right foods?
o Child nutritional status – anthropometric indicators
o People’s epeiee ith food iseuit
• Development goal
o By 2015 reduce the percentage of world hunger by 50% (measure in people)
• If the population need more calories than the amount of calories available then there is food insecurity
find more resources at oneclass.com
find more resources at oneclass.com
Letue : Doald “ith Cliate hage ad Agiultue … the oad ahead
• Overview
o Agriculture as an impact on climate change
o Impacts on agri
o Adaptations
o Mitigation
• Agriculture as a contributor
o We have changed things and things have changed
o Co2 concentration levels go up and down due to seasons (planet breathing in and out)
o The scale of it
▪ Globally, agriculture ranks third after energy consumption and chlorofluorocarbon (CFC)
production as a producer of greenhouse gasses
• Raks fo aout % oig fo agi soils, aue aageet ad …
o Greenhouse gases from agri
▪ Co2 carbon dioxide
▪ Ch4 methane
• More effective at heat traping
▪ N20 nitrous oxide
▪ Relative effect: co2:ch4:n20 -> 1:21:310
o Agricultural contributors
▪ 10% greenhouse gas emissions from agri
• not including transportation fuel emissions (its just agri production)
▪ Canadian agri is a small net sink fro co2 because of conversion to no-till
• N20 60% and methane 40% emissions from agri prod (no real co2 emissions due
to switch to no till)
o Co2
▪ Since ind rev sky rocket in co2 (since we started burning coal)
▪ Co2 sources
• Deforestation
o Much of the deforestation is associated with creating land area for food
production
o In north America most of this has occurred during the last 300 years
▪ From about 1700 to 1900, the clearing of northern hemisphere
forests for agriculture was the largest agent of change in the carbon
cycle
o The process is ongoing in places such as the Amazon basin
• Declining soil organic matter
o Tillage aerates soil and makes smaller particles enhancing oxidation of
organic matter
o Unless organic matter inputs (crop residues) are increase under agri soil
organic matter will decrease
o Methane
▪ Sources
• Rice paddies
o Soils are anaerobic
o Organic matter breaks down leads to methane prod
find more resources at oneclass.com
find more resources at oneclass.com
o Usually more than half of the methane escaping from the soil is oxidised
to co2 in the upper few mm of soil and the water
o The methane diffuses out oft the soil and also out through the plants via
aerenchyma (major route to the atmosphere)
o Just over half of agri emissions
• Livestock
o Ruminant livestock (sheeps, goats, buffalo etc.)
o Much is produced in the gut and is released by breathing, burping, and
flatulence (approx. 80% of the total)
o There are additional, and significant releases from decomposing manure
(approx. 20%)
o Just under half of current agri emissions
▪ Methane clathrates
• Methane trappes in water ice
o Fire ice
• Large amounts in the permafrost
• Clathrate melting may now be an issue
• Feed forward on climate change
▪ Methane trends
• Its current atmospheric concentration
o Nitrous oxide
▪ Sources
• Denitrification
• Nitrification (small amount)
• Concentration is now increasing at a rate of about 0.3% per year
• Up to 70% of the anthropogenic N20 emissions are agriculture
• Also contributes to the destruction of ozone
▪ Denitrification
• The end products of this ae N2 and N2o
• Soil mineral N can be denitrified when soils become anaerobic
o Eg. When there are periods of intense rain over several days or at snow
melt in the spring
o Can result in denitrification of up to several hundred KG on N in only a few
days
• Warmer soil temp will accelerate denitrification
• Impacts
o It will get warmer
▪ Model indicate that global average surface will rise by 1.5%-4.5% over this century
▪ Increases will be smallest at the equator and greatest at the poles
▪ Night temperature have increased more than day temperatures
▪ Greater change during winter than in summer
• When its cold there is less moisture in the air which is then a lower buffer against
weather change
o Artic sea ice minima over time decreasing
o Seasons will get long
▪ At higher latitude, were the length of the growing season is set by the time of last spring
and first fall frosts, the potential growing seasons will be longer
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
In developed countries we waste 25-30: food pillars, food sovereignty (take a look at the term, right to adequate food, food is a human right. If the population need more calories than the amount of calories available then there is food insecurity. Le(cid:272)tu(cid:396)e (cid:1007): do(cid:374)ald (cid:373)ith (cid:862)cli(cid:373)ate (cid:272)ha(cid:374)ge a(cid:374)d ag(cid:396)i(cid:272)ultu(cid:396)e the (cid:396)oad ahead(cid:863: overview, agriculture as an impact on climate change. 80% of the total: there are additional, and significant releases from decomposing manure (approx. 20%: just under half of current agri emissions, methane clathrates, methane trappes in water ice, fire ice, large amounts in the permafrost, clathrate melting may now be an issue, feed forward on climate change, methane trends. In california it will get drier) and other places will benefit (so should pick up the slack) Have developed based on this extra water availability for food production: many of these glaciers feed rivers whose waters are utilised for food production.
