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Urban stream water quality - trends - 2008–15
Ministry for the EnvironmentUrban water quality indicators include heavy metals, nutrients, and E.coli. The concentrations of these indicators are compared to the proportion of urban land cover in catchments. Zinc and copper are heavy metals that can accumulate in sediments, shellfish, and other aquatic organisms. Metals can reach toxic levels in organisms making them unsafe to eat...Created 2 February 2020 • Updated 3 March 2025 -
Freshwater pests: Senegal tea
Ministry for the Environment"Freshwater plant and animal pests can have significant negative impacts on ecosystem health by reducing indigenous biodiversity through predation and competition, and destabilising aquatic habitats. Freshwater plant pests can cause economic losses through blocking water intakes for hydroelectricity generation, impeded drainage or irrigation. In addition,...Created 2 February 2020 • Updated 3 March 2025 -
Groundwater pesticides survey, 2014
Ministry for the EnvironmentPesticides, which include insecticides, fungicides, herbicides and plant growth regulators, are commonly used in New Zealand to control insects, diseases and weeds in primary industries such as agricultural farming, forestry and horticulture. Once applied to land or crops, pesticides can make their way through soil and enter groundwater systems. File...Created 2 February 2020 • Updated 3 March 2025 -
Freshwater pests: Water lettuce
Ministry for the Environment"Freshwater plant and animal pests can have significant negative impacts on ecosystem health by reducing indigenous biodiversity through predation and competition, and destabilising aquatic habitats. Freshwater plant pests can cause economic losses through blocking water intakes for hydroelectricity generation, impeded drainage or irrigation. In addition,...Created 2 February 2020 • Updated 3 March 2025 -
Conservation status of native freshwater fish and invertebrates, 2013
Ministry for the EnvironmentNew Zealand has a diverse range of freshwater species. Many of these species are endemic to (only occur in, or only breed in) New Zealand. Freshwater fish and invertebrates are indicator species for the state of our freshwater environment. A decreasing population can indicate that the ecosystem is degrading. This measure reports on the conservation status...Created 2 February 2020 • Updated 3 March 2025 -
Average estimated national groundwater volume per year, 1994-2014
Ministry for the EnvironmentGroundwater is the water stored beneath Earth’s surface in aquifers (layers of water-bearing rock or sand). It is used for human and stock drinking water, irrigation, and industry, and also has a role in sustaining some rivers, lakes, and wetlands, especially during low-flow periods. The health of surface-water ecosystems also depends on groundwater....Created 2 February 2020 • Updated 3 March 2025 -
Recruitment of indigenous tree sp red beech 2002–2014
Ministry for the Environment"The rates of establishment (recruitment) of indigenous tree species vary across New Zealand. Changes in the state of the environment (such as from browsing pests, large-scale weather events, or climate change) may change the rates of recruitment of particular tree species. This in turn may alter forest processes. Repeated surveys of the distribution of...Created 2 February 2020 • Updated 3 March 2025 -
National PM10 exceedances 2006–13
Ministry for the EnvironmentParticulate matter 10 micrometres or less in diameter (PM10) in the air comprises solid particles and liquid droplets from both natural and human-made sources. PM10 can be emitted from the combustion of fuels, such as wood and coal (eg from home heating and industry), and petrol and diesel (from vehicles). Natural sources of PM10 include sea salt, dust,...Created 2 February 2020 • Updated 3 March 2025 -
Predicted river water quality, 2009–13
Ministry for the EnvironmentRiver water quality is valued for many reasons including ecological function and habitat, recreational value, its role in supporting people and industry, and its cultural significance. Nutrients such as nitrogen and phosphorus are essential for plant growth, however too much in rivers can lead to excessive growth of river algae, which can degrade habitat....Created 2 February 2020 • Updated 3 March 2025 -
Methane concentrations at Baring Head (1989–2013)
Ministry for the EnvironmentGreenhouse gases (GHGS) in the atmosphere absorb heat radiating from Earth, warming the atmosphere. Emissions from human activities increase the concentrations of these gases. Increases in these gases increase ocean acidity and are extremely likely to contribute to increased global temperatures, sea levels, and glacier melt. monitoring GHG concentrations...Created 2 February 2020 • Updated 3 March 2025 -
Notified cases of campylobacteriosis and cryptosporidiosis (1997–2013)
Ministry for the EnvironmentBacteria and parasites like campylobacter, salmonella, and cryptosporidium can contaminate our food and water, leading to serious illness. Campylobacter, salmonella, and cryptosporidium are influenced by temperature and other climate variables, and incidence rates may increase as climate change causes temperatures to rise. Monitoring the incidence rates...Created 2 February 2020 • Updated 3 March 2025 -
River water quality trends by monitoring site, 1989-2013
Ministry for the EnvironmentRiver water quality water is valued for many reasons including ecological function and habitat, recreational value, its role in supporting people and industry, and its cultural significance. Nutrients such as nitrogen and phosphorus are essential for plant growth, however too much in rivers can lead to ‘nuisance’ growths of river algae and aquatic plants,...Created 2 February 2020 • Updated 3 March 2025 -
Total Nitrogen trends, 1989–2013
Ministry for the Environment"Small amounts of nitrogen are a natural component of healthy rivers. Nitrogen is transferred from land to water and is cycled through different forms, which can have different effects. Moderate concentrations of nitrate can cause weeds and algae to grow too fast. High concentrations of ammoniacal and nitrate nitrogen can be toxic to fish and other...Created 2 February 2020 • Updated 3 March 2025 -
Ocean storms (1979–2015)
Ministry for the EnvironmentThe ocean storm index estimates the number of days in a year when wind speeds exceed gale and storm force on the Beaufort Scale. In a gale, sea conditions are rough and waves can be over six metres high. In a storm, waves can be over 10 metres high. To put this into context, on land a near gale would make walking difficult, and a storm would cause some...Created 2 February 2020 • Updated 3 March 2025 -
Influenza hospital discharges (2000–13)
Ministry for the EnvironmentInfluenza is a potentially life-threatening virus that spreads quickly from person to person. It is a significant public health issue in this country, with 10–20 percent of New Zealanders infected every year. While influenza outbreaks can occur all year round, rates peak in winter and spring. This is because the virus can survive longer outside the body...Created 2 February 2020 • Updated 3 March 2025 -
Total phosphorus trend, 1989–2013
Ministry for the Environment"Phosphorus is an essential nutrient for plant and animal life. Total phosphorus (TP) includes all concentrations in a sample, whether dissolved, in solid form or bound to sediment in the river. Dissolved reactive phosphorus (DRP) is the portion which is dissolved and can immediately support plant and algae growth. Excess phosphorus in our rivers can...Created 2 February 2020 • Updated 3 March 2025 -
Freshwater pests: Reed sweetgrass
Ministry for the Environment"Freshwater plant and animal pests can have significant negative impacts on ecosystem health by reducing indigenous biodiversity through predation and competition, and destabilising aquatic habitats. Freshwater plant pests can cause economic losses through blocking water intakes for hydroelectricity generation, impeded drainage or irrigation. In addition,...Created 2 February 2020 • Updated 3 March 2025 -
Maximum Ozone Concentration - Selected Auckland Locations
Ministry for the EnvironmentMaximum ozone concentration during 8-hour periods. Note: Ozone concentrations are given in micrograms per cubic metre of air, or µg/m3. Source: Auckland CouncilCreated 2 February 2020 • Updated 3 March 2025 -
Nitrogen dioxide concentrations and exceedances
Ministry for the EnvironmentNitrogen dioxide (NO2) is a gas. It can be emitted directly into the air but is most often formed when nitric oxide (NO) emissions react with other chemicals in the air. Nationally, road motor vehicles are the main human-made source of nitrogen oxides (NOx, the collective term for NO2 and NO). NO2 may cause respiratory infections and reduced lung...Created 2 February 2020 • Updated 3 March 2025 -
Annual Average PM10 Concentration - Selected Urban Centres
Ministry for the EnvironmentNote: PM10 concentrations are given in micrograms per cubic metre of air, or µg/m3. Source: Regional councils of Waikato, Wellington, Canterbury, Otago; Auckland CouncilCreated 2 February 2020 • Updated 3 March 2025