From Farm to fork: how food choices affect Ecosystems, Soils and Food

Certain human activities, when poorly planned or carried out on a large scale – such as pollution, deforestation or certain agricultural practices – profoundly alter ecosystems, degrade soils and reduce biodiversity. They can acidify the soil (through excessive use of fertilisers or atmospheric deposition) or cause salinisation (through inappropriate irrigation practices), increase erosion and hinder water infiltration and retention, thereby compromising the production of sufficient and nutritious food. In Portugal, forest fires weaken the soil, making it more vulnerable to erosion and less capable of supporting crops. Climate change and air pollution exacerbate this situation: higher temperatures, less predictable water supplies and pollutants such as ozone directly reduce agricultural productivity.

Ecological succession

Ecological succession and living soils

Following a disturbance (fire, erosion), ecosystems evolve through succession: pioneer species improve the soil and pave the way for greater diversity. Vegetation cover, hedgerows and agroforestry are based on the principles of ecological succession.

When soils are healthy, they help to mitigate these impacts: they store carbon, regulate water and nutrients, and support soil life. Practices such as crop rotation, cover crops, compost, careful nutrient management, agroforestry and even biochar improve soil quality, increase resilience to droughts and floods, and reduce emissions.

Energy management and food transport

The energy associated with food goes far beyond cultivation: it includes harvesting, the cold chain, packaging, transport, and storage in shops and at home. ‘Food miles’ (the distance food travels) contribute to the environmental footprint, although they do not, on their own, account for the food’s entire impact.  Generally speaking, sea and rail transport have a much smaller footprint per kilogram than air transport and, in many cases, than long-distance road transport. Food consumed in season and locally tends to require less energy and less reliance on the cold chain.

Water and air pollution in food production

Intensive farming uses fertilisers and pesticides on a large scale; a significant proportion is not absorbed, seeping into the soil and reaching rivers and aquifers. Nitrates are particularly problematic as they contaminate drinking water and cause eutrophication (algal blooms and oxygen depletion). Intensive livestock farming emits methane and produces slurry (liquid effluent resulting mainly from livestock farming: a mixture of animal urine and faeces with wash water, feed residues and small particles of bedding) which, if poorly managed, pollutes soil and watercourses. The burning of biomass and the use of fossil fuels in transport and processing release particulate matter that exacerbates respiratory diseases. Reducing these impacts requires good agricultural practices, the use of less persistent pesticides, nutrient management, and the recovery of manure and other livestock effluents.

Environmental labels: how to read and compare them

There are labels based on production standards (e.g. organic, animal welfare) and labels based on impact calculations (footprints, environmental scores). There is no single methodology: they differ in what they measure (water, carbon, soil, biodiversity, chemicals), in the quality/verification of data and in transparency.
How to use them in everyday life:

  • Check what the label covers – carbon only, or also water, soil and biodiversity.
  • Search for independent verification and date of the assessment.
  • Avoid comparing different labels
  • A ‘A’ rating for carbon does not, for example, make up for a high impact on water consumption or biodiversity.

 

 

FOODWISELAB ECOLOGICAL FOOTPRINT CALCULATOR

When planning your next trip to the supermarket, upload your latest supermarket receipt to our calculator and see the environmental impact of the food products you’ve bought. Now make your shopping list, avoiding those products that are most harmful to the environment.

The Ecological Footprint Calculator summarises the impact of a food item throughout its life cycle. The assessment is based on a life-cycle analysis calculated using data from receipts, and the following results are then returned: CO₂ (kg), CH₄ (kg), N₂O (kg), water consumption, energy consumption, type of packaging, transport distance and seasonality.

Based on the results, an impact score is generated for each food item. In summary, the Ecological Footprint Calculator provides a concise and comparative overview of environmental impact; it is transparent regarding its calculation rules and is constantly evolving, so it should be viewed as a comparative indicator rather than an absolute measure.

 

 

WASTE INTEGRATION AND THE CIRCULAR ECONOMY

A sustainable food system based on the principles of the circular economy, which seeks to reduce waste and reuse resources. Today, a considerable proportion of food is lost on the journey from farm to fork, as well as at home. This waste represents all the water, soil, energy and labour that went into producing it.
Solutions: appropriate portion sizes, making the most of leftovers (broths, soups, pancakes, tortillas made from leftovers), composting of bio-waste to return nutrients to the soil, and circular packaging (reusable, recyclable or biodegradable).

Planning your meals: a practical checklist
Planning your meals: a practical checklist
  • Place and season Firstly: seasonal fruit and vegetables require less cold-chain storage and transport.
  • He prefers foods that do not require air transport or long cold chains, as these options significantly increase the environmental footprint of each meal.
  • Plant-based foods in your daily diet: vegetables, whole grains and pulses; meat and fish in moderate portions and from sustainable sources.
  • Read the environmental label with a critical eye: what it measures, how it measures it and who verifies it.
  • Energy and cooling: organise your fridge so you can rotate your food, cook the right portions, or plan how to make the most of it.
  • Zero waste: shopping list, ‘first in, first out’, freeze food properly and compost anything that isn’t edible.
  • Whenever possible, choose reusable or recyclable packaging – this helps to reduce waste and the energy needed to produce new packaging.

 

Even when you need to import goods, products shipped by sea can have a much lower carbon footprint per kilogram than those transported by air.
Avoiding waste is one of the quickest ways to reduce the carbon footprint of your diet; every well-planned meal saves water, soil and energy.

INGREDIENTS ON THE PLATE

Material resources: soil, water, nutrients (N, P, K) – the basis of soil fertility and food quality.
Energy resources: electricity and fuels for pumping water, heating greenhouses, cooling and transporting food.
Renewable vs non-renewable: using solar and wind power for irrigation and greenhouses, and opting for sea or rail transport, reduces the energy footprint.
When planning: seasonal and locally sourced menus require less refrigeration and involve fewer kilometres.

 

 

FOODWISElab CHALLENGE

A land that nourishes

Protected areas and land-use planning instruments safeguard soil, water and pollinators.
Getting to know the areas in your region helps you appreciate products that coexist with conservation (wild honey, rain-fed fruit, fish from well-managed areas).


PLAN YOUR DIET AND PROTECT THE SOIL