Environment of New Zealand

The environment of New Zealand is characterised by an endemic

Historically having an isolated and endemic ecosystem far into modernity, the arrival of Polynesians about 1300 AD^[3] and then later European settlers began to have significant impacts on this system, with the intentional and unintentional introduction of new species and plants which often overwhelmed their natural competitors, leading to a significant loss of native ecology and biodiversity, especially in areas such as bird life.

Today, most parts of New Zealand are heavily modified by the effects of logging, agriculture and general human settlement, though large areas have also been placed under protection, combined in many cases with efforts to protect or regenerate native ecosystems (aided by the fact that especially the South Island of New Zealand has a very low population density).

Physical environment

Natural disturbances

New Zealand has many natural disturbances to its environment which endemic species have evolved to tolerate. These include local events with short return times like landslides, floods,

New Zealand's soils are affected by bedrock, climate, vegetation and the time it has had to develop, In the central North Island the felsic volcanic rocks is deficient in elements (like cobalt) needed by plants.^[6] While the rare ultramafic rocks of the South Island are so rich in required elements it is used as fertilizer.^[7] The warmer climate of Northland weathers rock more quickly leading to deeper soils. In Fiordland and similar wet steep environments landslides reduce the time for soil formation.

Climate

The main geographic factors that influence New Zealand's climate are the temperate latitude, with prevailing westerly winds; the oceanic environment; and the mountains, especially the

Ecosystems and ecology

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Biota of New Zealand
Biodiversity Flora and Fauna Amphibians Birds Butterflies Cicadas Crabs Fish Geckos Mammals Molluscs Moths Reptiles Spiders Trees Wētā Extinct animals Extinct plants Invasive species
Conservation Protected areas Conservation parks National parks Regional parks Marine reserves Wetlands
Organisations National DoC EPA Forest & Bird MfE SPCA International CITES IUCN WAZA WAP WWF
Associated laws New Zealand environmental law Conservation Act 1987 Wildlife Act 1953
Related topics 1080 usage Agriculture Animal welfare Aquaculture Climate change Deforestation Ecoregions Environment Fishing Natural history Tourism Wildlife smuggling
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New Zealand has a wide variety of ecosystems and classification methods for them.

New Zealand has a richly varied flora of imported and native species, the indigenous varieties having developed quite significantly due to the geographic isolation of the country before human migration and plant imports became common. However, the combination of external factors such as climate change and invasive species, as well as increasing agricultural and other human land uses

New Zealand's

Conservationists recognised that threatened bird populations could be saved on offshore islands, where, once predators were exterminated, bird life flourished again. Around 30 species are listed as endangered. The flightless kiwi, a national symbol, is also under threat.^[15]

Forests

Native New Zealand forests (or "

Temperate forests vary across the country, but prefer warmer environments to the beech forests. They are noted for the many canopy layers they have. Near the coast they become stunted[18] due to salt and exposure to wind.

Beech forests are divided into four varieties based on the dominant tree species and their geographic distribution is largely related to elevation.^[19] Black Beech (or Hard Beech) forests are found in the warmer lowlands of the North Island and northern South Island. Red Beech are found in direr foothills, while Silver Beech occupy a similar elevation but prefer a wetter environment. Mountain Beech are found at high elevation near the tree line, which in New Zealand is below 1000 m.

Beech trees do not flower every year, a year in which they flower is called a mast (or mast year). The effect of the whole canopy flowering at the same time introduces a lot of food into forest at once and leads to a population spike in those species that can quickly respond (typically mice).

New Zealand had a 2018 Forest Landscape Integrity Index mean score of 7.12/10, ranking it 55th globally out of 172 countries.^[20]

Grasslands

New Zealand has extensive natural tussock grasslands in locations where elevation and climate has limited forest growth.^[21] This includes the Central Plateau in the North Island and extensive areas of the South Island between the tree line and the alpine environment. There are also smaller areas of tussock grassland on flood plains due to the constantly shifting substrate and greater likelihood of frost. New Zealand's grassland ecosystems evolved in the absence of grazing mammals. Birds (Moa) and invertebrates were the main browsers until the introduction of sheep, goats and deer in the 1800s. Multiple species of tussock are present and dominate at different elevations and climates, with the maximum size of the species decreasing with increasing altitude.^[18] Tussock grasslands also help transfer water from the upper to lower catchment due to comparatively low transpiration.^[22]

Alpine

New Zealand has two main ecosystems where cold and high winds limit biological activity.^[23] As the Southern Alps were uplifted relatively recently far from other mountain chains the New Zealand biota has quickly adapted to the new environment. Superficially New Zealand's sub-antarctic islands are similar to the sub alpine zone.

Rivers and wetlands

New Zealand lakes, rivers and wetlands are the most threatened of the countries major ecosystems. Many coastal rivers have been dammed and most of New Zealand's wetlands have been drained.^[24] The damming of river can greatly change the sediment content and water flow.^[25]

Coastal

Dune systems are constantly moving and plants have adapted to this environment.^[26] Vegetation is stunted due high winds and salt. In the North Island large mangrove forests have formed.

Marine

Including the inter-tidal zone, the Marine ecosystem is by far New Zealand's largest and most diverse.^[27] It extends from the sub-tropics to sub antarctic waters, more than 30° of latitude. Less than 1% of the area has been surveyed in detail and about 150 new species are discovered every year. The marine environment has been heavily affected by fishing and the introduction of exotic species.

Rare natural ecosystems

Currently there are 72 recognised rare terrestrial ecosystems in New Zealand.^[28][29] They are environments that were always relatively uncommon like caves, serpentine soils^[30] or hot springs^[31] and those which have become endangered. There are also ecosystems where the physical environment is largely controlled by animal activity, such as areas of significant guano deposition.^[32]

Cultural landscapes

Farmland and urban environments are marked by the high number of introduced species, that have not evolved to interact with each other in the same ecosystem. These landscapes can effect the local climate, such as the 2.5 °C temperature rise in Christchurch from the urban heat island effect^[33] or the decreased transpiration from farmland.^[34] This increase in soil water content and reduction in the stabilising effects of roots leaves deforested areas prone to soil loss and landslides.^[35]

Unsustainable practices

As with many other countries there are a number of

Deforestation in New Zealand is now of negligible concern since logging indigenous forest on public land has ceased and it requires a permit to be carried out on privately owned land. In the past 800 years of human occupation New Zealand has lost about 75% of its forests due to deliberately lit fires and land clearance.^[39]

The management of waste in New Zealand has become more regulated to reduce associated environmental issues.^{[citation needed]}

New Zealand pledged to reach zero GHG emissions by 2050.[46] In September 2020, The labour party promised to advance a target of 100% energy from renewable sources by 2030.^[47]

Politics and public opinion

The Values Party, the first ever national level environmental party, was formed in 1973. The Green Party of Aotearoa New Zealand, which was formed in 1991 and included some members from the defunct Values Party, was initially in Parliament as part of the Alliance Party.

The level of protection of the environment from the different political parties varies according to their position on the

The Nature Heritage Fund is a New Zealand Government funding body set up in 1990, and administered by the Department of Conservation, for the purchase of land which has significant ecological or landscape features.^[49]

To support community efforts, the Community Conservation Fund is available. Funding is for established community groups that have an ecological restoration project on public land that can be sustained after the two-year funding period.

There are also Biodiversity Funds.^[50][51]

Protected areas

Nearly 30 per cent of the land mass of New Zealand is in

The roots of New Zealand environmental law can be traced to the

The most significant Act of Parliament concerning environmental law was the passing of

New Zealand is a signatory to a number of treaties and international agreements:[56]

• The
  Framework Convention on Climate Change
  , 1992 – ratified on 8 September 1993
• The Convention on Biological Diversity, 1992 – ratified on 16 September 1993
• The Montreal Protocol on Substances that Deplete the Ozone Layer, 1989 – ratified on 21 July 1988
• The
  Antarctic Treaty
  , 1959 – ratified on 1 November 1960 – Convention for the Conservation of Antarctic Marine Living Resources, 1980 – ratified on 8 March 1982 – and others
• United Nations Convention on the Law of the Sea, 1982 – ratified on 19 July 1996
• The Basel Convention on the Control of Transboundary Movements of Hazardous Wastes and their Disposal, 1989 – ratified on 20 December 1994
• The
  Stockholm Convention
  on Persistent Organic Pollutants 2001 – ratified on 24 September 2004.
• Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter, 1971 (London [Dumping] Convention) – ratified on 30 April 1975 – and the International Convention for the Prevention of Pollution from Ships
  , 1973 – not yet ratified
• The
  Convention on International Trade in Endangered Species
  of Wild Flora and Fauna, 1973 – acceded to on 10 May 1989
• The Convention on Wetlands of International Importance especially as Waterfowl Habitat, 1971 (Ramsar Convention) – signed on 13 August 1976 with effect from 13 December 1976
• Convention for the Prohibition of Fishing with Long Driftnets in the South Pacific, 1989 (Wellington Convention) – ratified on 17 May 1991
• South Pacific Nuclear Free Zone Treaty
  , 1985 – ratified on 13 November 1986
• Convention for the Protection of the Natural Resources and Environment of the South Pacific Region, 1986 [SPREP] – ratified on 3 May 1990
• The Cartagena Protocol on Biosafety to the Convention on Biological Diversity – ratified on 24 February 2005

New Zealand is a depositary to the following environmental treaties:^[57]

• Convention on the Regulation of Antarctic Mineral Resource Activities
• Convention for the Conservation and Management of Highly Migratory Fish Stocks in the Western and Central Pacific Ocean (WCPFC)
• Convention for the Prohibition of Fishing with Long Driftnets in the South Pacific
• Protocol I to the Convention for the Prohibition of Fishing with Long Driftnets in the South Pacific
• Protocol II to the Convention for the Prohibition of Fishing with Long Driftnets in the South Pacific

Evaluations of New Zealand's environmental performance

State of the Environment reporting

The Ministry for the Environment has produced a number of reports on the State of the Environment in 1997^[58] in 2007,^[59] and 2016.^[60]

Environmental Performance Index

The Environmental Performance Index (EPI) is a method of quantifying and numerically benchmarking the environmental performance of a country's policies. It results in a score out of 100. In 2016 New Zealand scored 88 out of 100, and ranked 11 out of 132 countries.^[62] In 2010, in terms of ecosystem effects on water quality New Zealand scored 40.3 points out of 100 for ecosystem vitality for freshwater and was ranked 43rd out of 132 countries.^[63][64]

OECD environmental performance review

In 2007, the

• Timeline of the New Zealand environment
• Natural history of New Zealand
• Sustainability in New Zealand
• Waste in New Zealand
  • Electronic waste in New Zealand
  • Food waste in New Zealand
  • Litter in New Zealand
• Conservation in New Zealand
  • Invasive species in New Zealand
  • List of New Zealand animals extinct in the Holocene
• Environmental movement in New Zealand
• Pollution in New Zealand
  • Water pollution in New Zealand
  • Pesticides in New Zealand
  • Dirty dairying
• Deforestation in New Zealand
• Climate change in New Zealand

References