L6 Global Food Security Flashcards
What does the DPSIR Framework represent?
A chain of causal links starting with ‘Driving forces’ (economic sectors, human activities) through ‘Pressures’ (emissions, waste) to ‘States’ (physical, chemical and biological) and ‘Impacts’ on ecosystems, human health and functions, eventually leading to political ‘Responses’ (prioritisation, target setting, indicators, treaties)
Which are the two main impacts of food production and consumption?
- Pollution (pesticides, fertilisers, greenhouse gases), which leads to biodiversity loss, eutrophication*, climate change
- Resource depletion (biodiversity, water, phosphate, fuel)
Production appropiates 30% of land, 70% of water, and 20% of energy
*it occurs when the environment becomes enriched with nutrients, increasing the amount of plant and algae growth - Harmful algal blooms, dead zones, and fish kills are the results of eutrophication
Sustainability is context and time dependent.
True / False
True - it is a dynamic target
Which are the challenges for food security and sustainability by 2050?
- Food security: double the yield* / habitant
- Sustainability: divide by 4 (quarter) the impacts / ton
*yield = cosecha, amount produced
Enumerate the environmental impacts from most to least urgent.
- Biodiversity loss
- Nitrogen cycle
- Climate change
- Phosphate cycle
- Ocean acidification
- Land-use change
- Freshwater use
- Ozone depletion
The percentage of CO2 in the atmosphere is 0.04%.
True / False
How is the natural carbon cycle (land-atmosphere)?
True.
This cycle occurs via two main drivers; photosynthesis and respiration.
In photosynthesis, carbon dioxide is absorbed from the atmosphere to create a fuel for the plant, while respiration (from humans and animals) consumes oxygen and produces carbon dioxide.
How is the current carbon cycle?
Currently, combustion of coal and oil contribute aswell by a 1 or 2% to the atmosphere.
(Human contribution = 1-2%)
There is 78% of nitrogen (N2) in the atmosphere.
True / False
How is the natural nitrogen cycle?
True
Although nitrogen is very abundant in the atmosphere as dinitrogen gas (N2), it is largely inaccessible in this form (gas) to most organisms. Only when nitrogen is converted from gas into ammonia (NH3), it becomes available to primary producers, such as plants.
Yhe transformation of nitrogen into its many oxidation is highly dependent on diverse microorganisms, such as bacteria or fungi.
How is the current nitrogen cycle?
Human activity releases nitrogen into the environment by two main means: (a) combustion of fossil fuels and (b) use of nitrogen-containing fertilizers in agriculture.
(Human contribution = 100-200%)
Effects: acid rain, greenhouse effect, and eutrophication*
*caused when artificial fertilizers containing nitrogen and phosphorus are used in agriculture, the excess fertilizer may be washed into lakes, streams, and rivers
It causes overgrowth of algae or other microorganisms, which use up large quantities of oxygen and it an cause the death of other organisms living in the affected ecosystems.
(e.g., Algal bloom and dead zone in the Gulf of Mexico and Baltic Sea)
Does nitrogen fertiliser harm the environment?
Yes. It has been a key factor in the increased yields achieved by modern agriculture, however they also represent one of the largest sources of greenhouse gas (GHG) emissions from global agricultural production (43% GHG emissions).
This emissions harm terrestrial and aquatic biodiversity.
There has been an increase in meat consumption since 1950.
True / False
True.
Factory farming is deeply inefficient: 40% of global grain harvest and 70% of soy are used to feed livestock (“ganado”).
Which are the harmful effects of this?
In intensive production systems (using feed crops), 1 kg animal protein requires 6 kg plant protein.
Land and water used by feed crops could be used by food crops to feed human populations in need.
What can be a possible alternative to fix protein inefficiency of factory farming?
Protein-rich feed crops can be used for human direct (not indirect) consumption of plant protein.
Can this alternative be carried out with the use of “meat replacers”?
Yes, but better meat replacers (NPF*) are required, because old ones (such as tofu, tempeh) are very energy-intensive.
How can we reduce impacts of meat consumption and protein inefficiency?
- Biorefinery: technologies for sustainable use and convertion of biomass into the marketable products needed to meet the demands of the growing world population.
- Innovation: algae crops, drip irrigation systems*, and urban agriculture.
- Novel Protein Foods (NPF): low in energy and egg white
- Reduce food waste or recycle it
- Reduce overconsumption
- Diet change (less meat and diary - lacteos)
- It delivers water and nutrients directly to the plant’s root zone, in the right amounts, at the right time, so it saves water.
