Lake water quality state 2013–2017

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Creative Commons Attribution 4.0 International

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You must attribute the creator in your own works.

958
10
Added
16 Apr 2019

This dataset was first added to MfE Data Service on 16 Apr 2019.

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....

Table ID 99872
Data type Table
Row count 454
Services Web Feature Service (WFS), Catalog Service (CS-W), data.govt.nz Atom Feed

Lake water quality trends 2008–2017 1998–2017 and 1990–2017

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Creative Commons Attribution 4.0 International

You may use this work for commercial purposes.

You must attribute the creator in your own works.

917
9
Added
16 Apr 2019

This dataset was first added to MfE Data Service on 16 Apr 2019.

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...

Table ID 99873
Data type Table
Row count 609
Services Web Feature Service (WFS), Catalog Service (CS-W), data.govt.nz Atom Feed

Lake Submerged Plant Index, 1991–2016

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Creative Commons Attribution 3.0 New Zealand

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2449
20
Added
25 Apr 2017

This dataset was first added to MfE Data Service on 25 Apr 2017.

Submerged plants are good indicators of the ecological quality of lakes. Because they are attached to the bed of lakes, submerged plants are easy to observe and identify, and they are unable to move away from environmental changes. The plant species found within lakes can tell us about their level of habitat degradation and exotic weed invasion.

The file contains Lake submerged plant index scores for each sampling occasion.

Table ID 53606
Data type Table
Row count 248
Services Web Feature Service (WFS), Catalog Service (CS-W), data.govt.nz Atom Feed

Lake water quality trends, 2004-2013

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Creative Commons Attribution 3.0 New Zealand

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2997
74
Added
29 Sep 2015

This dataset was first added to MfE Data Service on 29 Sep 2015.

When nutrients accumulate in lakes (referred to as ‘nutrient enrichment’) above certain levels, they can make the lakes murky and green with algae, and lower oxygen levels. Lakes with extremely poor water quality are rarely suitable for recreation and provide poor habitats for aquatic species.

Trends in the following parameters are provided:
Trophic Level Index 3 (TLI)
Chlorophyll-a (CHLA)
Bottom-water dissolved oxygen (DObottom)
Ammoniacal nitrogen (NH4N)
Oxidised nitrogen (NO3N)
Total nitrogen (unfiltered) (TN)
Dissolved reactive phosphorus (DRP)
Total phosphorus (unfiltered) (TP)

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/DDui3u from the Ministry for the Environment dataservice.

This dataset relates to the "Lake water quality: Trophic Level Index" measure on the Environmental Indicators, Te taiao Aotearoa website.

Table ID 52538
Data type Table
Row count 3724
Services Web Feature Service (WFS), Catalog Service (CS-W), data.govt.nz Atom Feed

Lake water quality state percentiles, by monitoring site, 2009-2014

Licence

Creative Commons Attribution 3.0 New Zealand

You may use this work for commercial purposes.

You must attribute the creator in your own works.

2371
59
Added
29 Sep 2015

This dataset was first added to MfE Data Service on 29 Sep 2015.

When nutrients accumulate in lakes (referred to as ‘nutrient enrichment’) above certain levels, they can make the lakes murky and green with algae, and lower oxygen levels. Lakes with extremely poor water quality are rarely suitable for recreation and provide poor habitats for aquatic species.

Percentile calculations for the following parameters are provided:
Trophic Level Index 3 (TLI)
Chlorophyll-a (CHLA)
Bottom-water dissolved oxygen (DObottom)
Ammoniacal nitrogen (NH4N)
Oxidised nitrogen (NO3N)
Total nitrogen (unfiltered) (TN)
Dissolved reactive phosphorus (DRP)
Total phosphorus (unfiltered) (TP)

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/DDui3u from the Ministry for the Environment dataservice.

This dataset relates to the "Lake water quality: Trophic Level Index" measure on the Environmental Indicators, Te taiao Aotearoa website.

Table ID 52537
Data type Table
Row count 5632
Services Web Feature Service (WFS), Catalog Service (CS-W), data.govt.nz Atom Feed