World Freshwater Data - Page 4

Freshwater fish are an important component of freshwater ecosystems, have intrinsic biodiversity values and are a valued resource for Māori, recreational and commercial fishers. The presence of fish species can be affected by changes in catchment land cover and land use, in-stream habitat, fish passages (routes for moving up and down waterways), pests, and contaminants.

File contains predicted capture, including upper and lower confidence intervals for 11 fish species, including indices of native fish, exotic fish, and all fish, over the period 1977 ̶ 2015.

Flow is the volume of water passing a point over a certain time, and provides information about the availability of water for people and the environment. Overall, this affects how much water is available for irrigation, drinking water, hydroelectricity generation, and recreational activities. River flows also influence a waterway’s physical form, habitat, and ecological processes like migration, spawning, and food supply for aquatic life.

The file provides the estimated impact of upstream consents on the modelled median flow of a particular reach in the digital river network. This is calculated by upstream total consented takes by median flow.

River water quality is valued for many reasons including recreational value.
Escherichia coli (E.coli) can indicate the presence of pathogens (disease-causing organisms) from animal or human faeces, which can cause illness.

File contains the model outputs for E.coli concentrations as four different statistics for each river segment in New Zealand’s digital river network.

River 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.

High concentrations of nitrogen in the form of ammoniacal nitrogen and nitrate-nitrogen can be toxic to fish and other aquatic animals, and nitrate-nitrogen can be toxic to humans. Water clarity is a measure of underwater visibility, and affects habitat of aquatic life such as fish and birds, and can also impact on aesthetic values and recreational use of rivers and streams. Escherichia coli (E.coli) can indicate the presence of pathogens (disease-causing organisms) from animal or human faeces, which can cause illness.

File contains the model outputs for river water quality indicators as medians for each river segment in New Zealand’s digital river network.

River 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, degrading habitat. High concentrations in the form of ammoniacal nitrogen and nitrate-nitrogen can be toxic to fish and other aquatic animals. Water clarity is a measure of underwater visibility, and affects habitat of aquatic life such as fish and birds, and can also impact on aesthetic values and recreational use of rivers and streams. Escherichia coli (E.coli) can indicate the presence of pathogens (disease-causing organisms) from animal or human faeces, which can cause illness.

File contains raw data collected at regional council and NIWA monitored sites over the period 1975-2013. Fields are described as follows. Refer to Larned et al. 2015 for further details:
* nemarid ---- Unique NIWA ID
* lawaid ---- Unique LAWA ID
* rcid ---- Collection agency
* srcid ---- Region site is located in
* sflag ---- River (r) or Estuary (e)
* river ---- River name
* location ---- Name of site, assigned by collection agency
* nzmge ---- easting
* nzmgn ---- northing
* nzreach ---- REC1 segment identifier
* sdate ---- Sample date (yyyy-mm-dd)
* Q ---- Flow recorded when sample was taken (if available), cumecs
* npid ---- NIWA parameter ID (as used in Larned et al. 2015)
* lpid ---- LAWA parameter ID
* fdval ---- Parameter value (units are mg/m3, except CLAR (m) and ECOLI (n/100 mL))

For more information please see:
Larned, S, Snelder, T, Unwin, M, McBride, G, Verburg, P, McMillan, H (2015).Analysis of Water Quality in New Zealand lakes and Rivers: data sources, data sets, assumptions, limitations, methods and results. NIWA Client Report no. CHC2015-033. Available at data.mfe.govt.nz/x/Mo8VUY from the Ministry for the Environment dataservice.

This dataset relates to the "River water quality" measures on the Environmental Indicators, Te taiao Aotearoa website.

Groundwater 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.

Estimated national groundwater volumes by year and aquifer type (confined, or unconfined)
aquifer_ty = aquifer type
cubicm = estimated groundwater volume in cubic metres (m3)

This dataset relates to the "Groundwater physical stocks" measure on the Environmental Indicators, Te taiao Aotearoa website.

Groundwater 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.

Estimated average groundwater volumes by 16 regional councils
* region = Regional Council
* bil_cubicm = Average estimated groundwater volume in billion cubic metres

For more information please see:
Moreau M, & Bekele, M (2015). Groundwater Component of the Water Physical Stock Account (WPSA) GNS Science Consultancy Report 2014/290. 35p. Available at data.mfe.govt.nz/x/Tebsax from the Ministry for the Environment dataservice.

This dataset relates to the "Groundwater physical stocks" measure on the Environmental Indicators, Te taiao Aotearoa website.

We report on trends in nitrate-nitrogen from livestock that has leached from soil per year across New Zealand since 1990.

Nitrogen is an essential nutrient for plant growth. It occurs naturally, but in agricultural systems more nitrogen is commonly added to soils as fertiliser or as urine or dung from livestock. Not all the additional nitrogen can be used by plants and microorganisms, so some nitrate-nitrogen may leach (drain) from the soil. Livestock urine is the dominant source of nitrate-nitrogen leached from soil. Leached nitrate-nitrogen can enter groundwater and waterways, potentially causing ecological harm. The amount of nitrate-nitrogen leaching from the soil varies around the country as a result of different land uses, climates, and soils.

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 www.mfe.govt.nz/publications/fresh-water/spatial-n...

This dataset contains ten lake water quality variables based on measurements made at monitored lake sites: chlorophyll-a, nitrate-nitrogen, total nitrogen, ammoniacal nitrogen, dissolved reactive phosphorus, total phosphorus, Escherichia coli, water clarity, and lake trophic level index (TLI3 and TLI4). This dataset includes: - Median values for the period 2013 to 2017 - For selected indicators, how these values compare to the National Objectives Framework (NOF) (MfE, 2017) bands related to ecosystem health When nitrogen and phosphorus accumulate above certain concentrations in lakes (referred to as ‘nutrient enrichment’), they can stimulate excessive growth of algae and cyanobacteria. Chlorophyll-a is a measure of the phytoplankton (algae) biomass. The lake trophic level index (TLI) indicates the health of a lake based on concentrations of three variables:
· total nitrogen
· total phosphorus
· chlorophyll-a.

Water clarity is a measure of underwater visibility. Lakes with poor clarity and TLI are poor habitats for some species of animals and plants, and they may not be suitable for recreation. Ammoniacal nitrogen can be toxic to aquatic life if concentrations are high enough.

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: www.mfe.govt.nz/publications/fresh-water/water-qua...