Now showing items 1-20 of 26

  • Applying citizen science to freshwater ecosystem restoration – fact sheet

    Peters, Michael A.; Hamilton, David P. (Lake Ecosystem Restoration New Zealand (LERNZ), University of Waikato, 2015)
    Citizen science describes the diverse ways in which the public participates in scientific investigations. Participation covers a spectrum from sending observations to a project coordinator to designing, implementing ...
  • Catchment modelling with SWAT – fact sheet

    Me, W; Hamilton, David P. (Lake Ecosystem Restoration New Zealand (LERNZ), University of Waikato, 2015)
    Catchment models determine the source and extent of water quality problems in a catchment. Catchment models may be used to identify 'hotspots' in a region and once calibrated these models may be used to test various land ...
  • The contribution of lakes to greenhouse gas emissions – fact sheet

    Santoso, A; Hamilton, David P. (Lake Ecosystem Restoration New Zealand (LERNZ), University of Waikato, 2015)
    Greenhouse gases such as carbon dioxide (C0₂) , methane (CH₄) and nitrous oxide (N₂0) trap heat in the atmosphere. Lakes can play an important role in regulating these gases at global scales. Total carbon uptake by lakes ...
  • Destratification – fact sheet

    Tempero, Grant Wayne; Paul, Wendy J. (Lake Ecosystem Restoration New Zealand (LERNZ), University of Waikato, 2015)
    During summer, the surface waters of lakes warm and become less dense than the colder bottom waters. This process is known as stratification and prevents surface and bottom water mixing. Stratification can occur intermittently ...
  • Effects of introduced fish on zooplankton – fact sheet

    Duggan, Ian C. (Lake Ecosystem Restoration New Zealand (LERNZ), University of Waikato, 2015)
    Zooplankton are small animals that feed on algae and bacteria in lakes, and are in turn food for small fish. Three major zooplankton groups exist in lakes; the cladocerans and copepods, which are both small crustaceans, ...
  • Exclusion and removal of pest fish from Lake Ohinewai – fact sheet

    Tempero, Grant Wayne; Ling, Nicholas; Daniel, Adam Joshua (Lake Ecosystem Restoration New Zealand (LERNZ), University of Waikato, 2015)
    Many of the shallow lakes in the lower Waikato River floodplain have significantly degraded water quality as a result of nutrient and sediment enrichment from non-point sources. Pest fish species such as koi carp, goldfish, ...
  • Flocculation and sediment capping – fact sheet

    Tempero, Grant Wayne; Paul, Wendy J. (Lake Ecosystem Restoration New Zealand (LERNZ), University of Waikato, 2015)
    Sediment capping and flocculation are in-lake techniques designed to reduce internal nutrient loads from the bottom sediments of lakes. These loads are roughly equivalent in magnitude to external loads. Case studies of the ...
  • Genetic tools – fact sheet

    Hogg, Ian D. (Lake Ecosystem Restoration New Zealand (LERNZ), University of Waikato, 2015)
    Morphological identification of organisms can be challenging and often requires specialist knowledge to ensure accurate identifications especially, if specimens are microscopic, as is the case with zooplankton (Figure 1). ...
  • Invasive fish and nutrients – fact sheet

    Hicks, Brendan J. (Lake Ecosystem Restoration New Zealand (LERNZ), University of Waikato, 2015)
    Invasive fish such as koi (or common) carp (Cyprinus carpio) are large fish as adults (typically 1-3 kg) and can exist at high biomass (commonly 1000-2000 kg/ha). Because of their large size, high biomass, and suctorial ...
  • Lake models – fact sheet

    Hamilton, David P. (Lake Ecosystem Restoration New Zealand (LERNZ), University of Waikato, 2015)
    Models of lakes are used to provide insights into water quality at some future point in time, so that management actions may be targeted and cost-effective. In the past, small-scale physical models were used to simulate ...
  • Lake restoration lags – fact sheet

    Mueller, H; Hamilton, David P. (Lake Ecosystem Restoration New Zealand (LERNZ), University of Waikato, 2015)
    Regulatory responses to declines in lake health have often been characterised by long lag times. Under these circumstances regulation has often failed to prevent declining lake health or to implement successful restoration ...
  • LakeAnalyzer: Lake internal dynamics analysis software – fact sheet

    Muraoka, Kohji; Hamilton, David P. (Lake Ecosystem Restoration New Zealand (LERNZ), University of Waikato, 2015)
    LakeAnalyzer is a computer program used to calculate indices of mixing and stratification, which are critical to understanding biogeochemical cycles of lakes and reservoirs. Lake physical stability indices, surface mixing ...
  • Legal status of Rudd, Catfish, Goldfish – fact sheet

    Collier, Kevin J. (Lake Ecosystem Restoration New Zealand (LERNZ), University of Waikato, 2015)
    New Zealand has a total of about 36 native freshwater fish species, and a further 22 species (equivalent to 38% of all freshwater fish species) have been introduced from overseas. Like all introduced species, they have ...
  • LERNZ: Lake Ecosystem Restoration New Zealand – Fact Sheet

    Tempero, Grant Wayne; Hamilton, David P. (Lake Ecosystem Restoration New Zealand (LERNZ), University of Waikato, 2015)
    Based at the University of Waikato (Figure 1), the aim of the LERNZ research programme is to provide end-users such as community groups, regional councils and governmental agencies with practical tools and expertise for ...
  • LERNZdb Freshwater Database – fact sheet

    Parshotam, A. (Lake Ecosystem Restoration New Zealand (LERNZ), University of Waikato, 2015)
    The LERNZdb Freshwater Database is a repository for freshwater quality data and biodiversity measurement data for lakes, rivers and wetlands in New Zealand. It was developed as part of the Lake Ecosystem Restoration New ...
  • New Zealand pest fish species: Koi carp and Gambusia – fact sheet

    Tempero, Grant Wayne (Lake Ecosystem Restoration New Zealand (LERNZ), University of Waikato, 2015)
    New Zealand has a total of about 36 native freshwater fish species, and a further 22 (39% of all freshwater fish) have been introduced from overseas. Like all introduced species, they have some impact on New Zealand's ...
  • Nutrient and sediment loads from farm drains – fact sheet

    Tempero, Grant Wayne; Hamilton, David P. (Lake Ecosystem Restoration New Zealand (LERNZ), University of Waikato, 2015)
    Runoff from intensive agriculture has been identified as a major contributor to the decline of New Zealand's freshwater ecosystems. Excessive nutrient and sediment losses to lakes and rivers lead to reduced water clarity ...
  • On the foreigner

    Arndt, Sonja Kathrina (Wilf Malcolm Institute of Educational Research, 2015)
    Who is ‘the foreigner’? What does it mean, to be a foreigner, and how does foreignness feel, look, or smell? A concrete definition of the foreigner would perhaps belie the very term, so I attempt here to illustrate the ...
  • Paleolimnology to determine lake reference conditions – fact sheet

    Kpodonu, A; Hamilton, David P. (Lake Ecosystem Restoration New Zealand (LERNZ), University of Waikato, 2015)
    Paleolimnology is the study of the early history of lakes based on sediment composition. Lake sediments build up in undisturbed areas of lake bottoms (e.g. in deep central basins) over long periods of time. These sediments ...
  • Pest Fish Control - Fact Sheet

    Tempero, Grant Wayne; Collier, Kevin J.; Hicks, Brendan J. (Lake Ecosystem Restoration New Zealand (LERNZ), University of Waikato, 2015)
    Due to their negative impacts on water quality and native biodiversity in New Zealand, regional councils have included a number of introduced freshwater fish species such as koi carp, rudd, brown bullhead catfish, goldfish, ...