Salmon farm marine harvest - ASC

Freshwater and oceans

Outcomes of interest for this issue:

Summary of the issue:

Freshwater and oceans

Freshwater and oceans are critical to the survival of all life on earth.  Freshwater is not only a major component of the bodies of living creatures but also, together with oceans, are regulators of global temperatures, rainfall patterns and other climatic features through the water cycle.

Our oceans generate half of the oxygen humans need to breathe. For many decades our human footprint on the oceans and on freshwater has been expanding due to chemicals used in farming and forestry, wastewater discharge, sedimentation, overfishing, coastal development, oil and gas extraction, deep-sea mining, shipping, tourism and other activities.

In freshwater, indiscriminate or excessive use of pesticides and fertilizers in agriculture, and of herbicides in forestry, and the release of domestic or industrial wastewater can contaminate waterways and threaten human and environmental health.  Sedimentation from soil erosion on farms and forestry operations can impair water quality and negatively affect downstream infrastructure such as urban water supplies and hydroelectric dams. In mining, the discharge of mine water or the seepage of mine waste into groundwater and surface water can affect water quality.  Accidents involving the breach of mining waste (tailings) containment areas can cause profound damage to freshwater systems needed for communities.

In oceans, climate change and overfishing are the two greatest threats (Gattuso, 2018).  In addition, the marine environment is negatively impacted by coastal habitat loss and chemical changes.  Chemical alterations result from plastic debris, toxic contaminants and eutrophication. Marine wildlife can be harmed by invasive species, vessel strikes and noise pollution. Scientists describe a bundle of ocean threats, sorted into four main human stressors: threats from climate change, threats from commercial fishing, threats from coastal habitat loss and threats from pollution (Glaser, 2015).

Many sustainability standards, certifications and related supply chain tools include provisions to reduce their participants’ negative impacts on freshwater and oceans. Often, farms, ranches, mills, factories, mines, processing facilities and other water users must monitor their intake and implement strategies to reduce it, maintain irrigation systems in good working order to avoid waste or leakage, and ensure that discharged wastewater or effluents comply with legal water quality requirements and in some cases additional pre-determined water quality parameters. Some standards require certified entities to implement water monitoring programmes as well as water quality sampling, or even to establish ‘trigger levels’ to alert operators to water quality problems.

In seafood standards and programmes, provisions might be included to choose fishing gear types that avoid marine habitat damage; or to detect illegal, unreported, and unregulated fishing where it occurs; or to limit the use of possible water contaminants in fish farms; or to otherwise reduce overfishing to keep fish stocks at a level that maintains the overall ecosystem health.

Some resources that examine the impact of standards and related tools on freshwater and oceans are as follows:

Available evidence

Linked outcomes of interest

Discover our interactive tools

Evidensia’s interactive tools help you find, understand and interpret evidence and evidence gaps.

Visual summaries

See what the evidence says on specific topics of interest.

View results

Geo maps

View what the site offers from a geographic lens.

View map

Knowledge Matrix

Find evidence on issues, sectors, products and tools and spot the gaps.

View matrix

You may also be interested in:

Issues :
Freshwater and oceans
View All