Oceania Data

This data set reports on state for the period 2016 to 2020.

Coastal and estuarine ecosystems are affected by changes in water quality.

Nutrients
The two main nutrients of concern in coastal and estuarine ecosystems are nitrogen and, to a lesser degree, phosphorus. An overload of nutrients (eutrophication) can lead to algal blooms that can kill marine life by depleting oxygen levels. Some bloom-forming algal species also contain toxins that can harm marine life, and can pass through food chains to humans (for example, via shellfish poisoning).

Microbiological
Abundant Enterococci _and faecal coliform bacteria indicate the possible presence of human faecal pathogens in coastal waters and represent the risk of infectious disease. Chlorophyll-_a is a measure of phytoplankton biomass and is a primary indicator of eutrophication.

Optical
High suspended sediment concentrations are associated with estuarine and coastal sedimentation, reduced light levels in benthic (seabed) environments, and reduced feeding rates and health of estuarine and coastal animals (Lowe et al., 2015). Visual clarity and turbidity are monitored because light affects primary production, plant and animal distributions and ecological health, aesthetic quality, and recreational values (Davies-Colley et al., 2003).

Physico-chemical
Dissolved oxygen is fundamental to supporting marine life. Low levels of dissolved oxygen can have adverse effects on aquatic fauna, from reduced growth rates to death from lack of oxygen (Tomasetti & Gobler, 2020). Decreased pH results from the absorption of CO2 from the atmosphere by seawater but can also reflect local processes caused by eutrophication (Cai et al., 2011; Fraser et al., 2021). Changes in the pH of seawater can have harmful effects on marine life, impacting chemical communication, reproduction, and growth. The building of skeletons in marine organisms is particularly sensitive to acidity, so acidification (lower pH) of sea waters can be harmful for organisms such as shellfish and corals (Fabry et al., 2008). Salinity provides information on the freshwater content of coastal waters. Water temperature is important as it controls biochemical processes and affects the balance of parameters such as dissolved oxygen levels. As a result, seawater temperature determines distributions of many marine plants and animals (Kleisner et al., 2017).

Adapted by Ministry for the Environment and Statistics New Zealand to provide for environmental reporting transparency. Dataset used to develop the "Coastal and estuarine water quality, trends" indicator (available at Coastal and estuarine water quality | Stats NZ).

This data set reports on trends for 15 coastal and estuarine water quality measures, grouped below by type, monitored at sites across Aotearoa New Zealand between 2006 and 2020:

• nutrient – ammoniacal nitrogen, nitrate-nitrite nitrogen, total nitrogen (unfiltered), dissolved reactive phosphorus, and total phosphorus (unfiltered)
• microbiological – faecal coliforms, Enterococci, and chlorophyll-a
• optical – visual clarity, turbidity, and suspended solids (inorganic and organic)
• physico-chemical – dissolved oxygen, pH, salinity, and temperature.

We present trends for the period 2011 to 2020.

Coastal and estuarine ecosystems are affected by changes in water quality.

Nutrients
The two main nutrients of concern in coastal and estuarine ecosystems are nitrogen and, to a lesser degree, phosphorus. An overload of nutrients (eutrophication) can lead to algal blooms that can kill marine life by depleting oxygen levels. Some bloom-forming algal species also contain toxins that can harm marine life, and can pass through food chains to humans (for example, via shellfish poisoning).

Microbiological
Abundant Enterococci _and faecal coliform bacteria indicate the possible presence of human faecal pathogens in coastal waters and represent the risk of infectious disease. Chlorophyll-_a is a measure of phytoplankton biomass and is a primary indicator of eutrophication.

Optical
High suspended sediment concentrations are associated with estuarine and coastal sedimentation, reduced light levels in benthic (seabed) environments, and reduced feeding rates and health of estuarine and coastal animals (Lowe et al., 2015). Visual clarity and turbidity are monitored because light affects primary production, plant and animal distributions and ecological health, aesthetic quality, and recreational values (Davies-Colley et al., 2003).

Physico-chemical
Dissolved oxygen is fundamental to supporting marine life. Low levels of dissolved oxygen can have adverse effects on aquatic fauna, from reduced growth rates to death from lack of oxygen (Tomasetti & Gobler, 2020). Decreased pH results from the absorption of CO2 from the atmosphere by seawater but can also reflect local processes caused by eutrophication (Cai et al., 2011; Fraser et al., 2021). Changes in the pH of seawater can have harmful effects on marine life, impacting chemical communication, reproduction, and growth. The building of skeletons in marine organisms is particularly sensitive to acidity, so acidification (lower pH) of sea waters can be harmful for organisms such as shellfish and corals (Fabry et al., 2008). Salinity provides information on the freshwater content of coastal waters. Water temperature is important as it controls biochemical processes and affects the balance of parameters such as dissolved oxygen levels. As a result, seawater temperature determines distributions of many marine plants and animals (Kleisner et al., 2017).

Adapted by Ministry for the Environment and Statistics New Zealand to provide for environmental reporting transparency. Dataset used to develop the "Coastal and estuarine water quality, trends" indicator (available at ++Coastal and estuarine water quality | Stats NZ++).

Adapted by Ministry for the Environment and Statistics New Zealand to provide for environmental reporting transparency. Dataset used to develop the "River water quality: Escherichia coli" indicator (available at www.stats.govt.nz/indicators/river-water-quality-e...).

This dataset contains one parameter of water quality based on modelled data for rivers:

• Escherichia coli

Escherichia coli in river waters is one of five parameters that provide an overview of New Zealand’s river water quality and how it is changing over time.

This dataset includes:

• E. coli concentrations modelled for New Zealand’s river segments without monitor sites for the period 2016–2020

More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf.

Summary report available at environment.govt.nz/publications/environment-aotea....

Note that this is a large dataset so is provided as a shapefile, and will need a GIS application to view.

Note that this is a large dataset so is provided as a shapefile, and will need a GIS application to view.

Adapted by Ministry for the Environment and Statistics New Zealand to provide for environmental reporting transparency. Dataset used to develop the "River water quality: phosphorus" indicator (available at www.stats.govt.nz/indicators/river-water-quality-p...).

Phosphorus in river waters is one of five parameters that provide an overview of New Zealand’s river water quality and how it is changing over time. Phosphorus is an essential nutrient for plants and is a natural component of healthy rivers. Agricultural and urban land use, and infrastructure such as wastewater treatments plants, can add more phosphorus to waterways, which can increase algae growth and biomass. This in turn causes deterioration of river habitats.

This dataset includes:

• concentrations of total phosphorus (TP) and dissolved reactive phosphorus (DRP) modelled for New Zealand’s river length, expressed as percentiles for the period of 2016–2020

More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf. Summary report available at environment.govt.nz/publications/environment-aotea...

Note that this is a large dataset so is provided as a shapefile, and will need a GIS application to view.

Adapted by Ministry for the Environment and Statistics New Zealand to provide for environmental reporting transparency. Dataset used to develop the "River water quality: macroinvertebrate community index" indicator (available at www.stats.govt.nz/indicators/river-water-quality-m...).

​

Benthic macroinvertebrates are small animals without backbones (for example, insects and worms). They live on and under submerged logs, rocks, and aquatic plants on the beds of rivers and streams during some part of their life cycle. Macroinvertebrates play a central role in stream ecosystems by feeding on periphyton (algae), macrophytes (aquatic plants), dead leaves and wood, or on each other. In turn, they are an important food source for fish and birds.

The macroinvertebrate community index (MCI) is used as an indicator of water quality and overall stream health. It is one of five parameters that provide an overview of New Zealand’s river water quality and how it is changing over time. This data shows:

• MCI scores as modelled median values for New Zealand’s river length for the period 2016–2020

More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf. Summary report available at environment.govt.nz/publications/environment-aotea....

​

Adapted by Ministry for the Environment and Statistics New Zealand to provide for environmental reporting transparency. Dataset used to develop the “River water quality: Nitrogen” indicator, (available at www.stats.govt.nz/indicators/river-water-quality-n...).

Nitrogen in river waters is one of five parameters that provide an overview of New Zealand’s river water quality and how it is changing over time. Nitrogen is an essential nutrient for plants and algae. Some nutrient supply is a natural component of healthy rivers, but agricultural and urban land use, and infrastructure such as wastewater treatment plants, can add more nitrogen to waterways. Too much nitrogen can lead to excessive growth of algae, which can deteriorate river habitats. In very high concentrations, some forms of nitrogen, including nitrate-nitrogen and ammoniacal nitrogen, can be toxic to aquatic life.

This dataset shows:

• concentrations of total nitrogen (TN), nitrate-nitrite-nitrogen (NNN) and ammoniacal nitrogen (NH4N) modelled for New Zealand’s river length, expressed as percentiles for the period 2016–2020

More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf.

Summary report available at environment.govt.nz/publications/environment-aotea...

Adapted by Ministry for the Environment and Statistics New Zealand to provide for environmental reporting transparency. Dataset used to develop the "River water quality: clarity and turbidity" indicator (available atwww.stats.govt.nz/indicators/river-water-quality-c...).

This dataset contains two attributes of water quality based on measurements made at monitored river sites:

• Clarity
• Turbidity

Clarity and turbidity in river waters is one of five parameters that provide an overview of New Zealand’s river water quality and how it is changing over time.

This dataset includes:

• clarity and turbidity as modelled median values for New Zealand’s river length for the period 2016–2020

More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf.

Summary report available atenvironment.govt.nz/publications/environment-aotea... .

Note that this is a large dataset so is provided as a shapefile, and will need a GIS application to view.

"River flow refers to the quantity of water passing a point in the river over a certain amount of time. Different rivers have different flow patterns, such as sharp peak flows following rain with low flows in between, or high spring flows from snow melt. These flow characteristics affect how much water is available for irrigation, drinking water, hydro–electric power generation, and recreational activities such as fishing and boating. River flows are also very important for maintaining the health and form of a waterway.

This dataset relates to the "Geographic pattern of natural river flows" measure on the Environmental Indicators, Te taiao Aotearoa website. "

For more information, refer to the March 2015 report: 'Hydrological indices for national environmental reporting' data.mfe.govt.nz/document/11463-hydrological-indic....

This layer is the total rainfall for the year 2016, summed from interpolated daily rainfall, in mm, not the average.

​

More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf.

This layer is the total rainfall for the year 2016, summed from interpolated daily rainfall, in mm, not the average.

More information on this dataset and how it relates to our environmental reporting indicators and topics can be found in the attached data quality pdf.