agriculture & eutrophication

sustainability in agriculture refers to the practice of cultivating & producing agricultural products in a way that preserves the long-term environmental, social & economic well-being of farming systems

• involves adopting practices that minimise negative impacts on environment, promote efficient resource use, protect biodiversity & support the livelihoods of famers & communities

what’re some factors that affect the sustainability of agriculture

soil erosion

lack or leaching of nutrients

supply of fertilizers & other inputs

pollution due to agrochemicals

carbon footprint

what is soil erosion

process that involves the detachment, movement & transportation of soil particles from one area to another

• this is a natural phenomenon, but humans greatly accelerate the rate of soil erosion

  • this has serious consequences - removing large areas of vegetation reduces the protective cover of the soil

    • without plants to hold the soil in place, the rate of soil erosion greatly increases

  • excessive grazing by livestock, or poor agricultural practices (such as improper ploughing) can also results in bare fields, which makes the soil susceptible to erosion by wind & water

what are agrochemicals

includes synthetic pesticides & fertilisers

this can hv significant effects on soil erosion & degradation

• some fertilisers can reduce pH levels of soil, leading to soil acidification

  • acidic soils are less productive, and therefore vulnerable to erosion

• they may also result in a decrease in soil organic matter

  • reduces the soil’s capability of holding nutrients & water, also making it vulnerable to erosion

excessive use of agrochemicals can also contaminate water bodies, harming human health & aquatic ecosystems

• pesticide use also harms beneficial insets, birds & wildlife, thus disrupting the ecological balance

water use

inefficient water use & improper management of agricultural runoff can lead to water scarcity & pollution

over-extraction of groundwater can deplete aquifers

if irrigation isn’t properly managed, excessive water application can result in leaching of nutrients beyond the crop root zone

• water-soluble nutrients can be carried downwards with excess water, effecting the souk

biodiversity

intensive agricultural practices often prioritise high-yielding crop varieties & livestock breeds, resulting in a loss of biodiversity

monocropping (planting only 1 type of crop) & genetic homogeneity make agricultural systems more vulnerable to pests, diseases & climate change impacts

deforestation & land conversion also reduces biodiversity, available habitats, & disrupts the ecosystem

carbon footprint

agricultural services release greenhouse gases

carbon footprint of agriculture contributes to the increasing concentrations of greenhouse gases in the atmosphere

• increase in temperature & unpredictable wind patterns pose challenges to agriculture

  • these challenges include extreme weather events, shifting patterns of pests & diseases, & altered growing seasons

  • these affect crop yields & livestock health

whats eutrophication

the process by which water bodies become enriched with excessive nutrients, particularly nitrogen & phosphorus, resulting in an overgrowth of algae & other aquatic plants. Eutrophication results in increased biochemical oxygen demand (the amount of dissolved oxygen needed by aerobic organisms to break down organic material)

• the excessive growth disrupts the balance of the ecosystem, & has dangerous consequences for aquatic health, aquatic life & overall ecosystem health

what are some reasons eutrophication is bad

it forms an impenetrable roof on the water, meaning light cannot penetrate through and reach the plants at the bottom of the water, that need light to photosynthesize

• plants can store some nutrients to help them survive in a period of time where they don’t have nutrients

  • the real problem arises when the nutrients are used up, and the water can no longer support so much life

    • the excess algae, phytoplankton & plants will die & sink to bottom of ocean

    • they will be decomposed by bacteria, which need oxygen in order to complete the decomposition process

      • if there are lots of dead matter because of the algae bloom, then a greater amount of oxygen will be needed in order to decompose the extra algae, which takes from the available oxygen for organisms

      • organisms that need oxygen to survive won’t have access to it, meaning they will suffocate and die

      • their bodies will be decomposed, which requires oxygen

      • so this is an example of a positive feedback loop

• the lack of oxygen in oceans may lead to coral bleaching and potentially coral death

• in lakes, invasive species can invade as the lake is vulnerable?

*check kognity (agriculture & eutrophication) for information on the process of eutrophication

percentage reduction formula (for farming)