What are drylands? Background information for a meeting to discuss drylands in the revised Nelson/Marlborough CMS Grant Norbury and Susan Walker Landcare Research, Dunedin and Alexandra March 2010

Drylands: Contain some of the most transformed, least protected and most threatened native ecosystems and species in New Zealand Are unstable, seral, rapidly changing, invaded

In seeking to protect and restore drylands, we face: Limited knowledge, experience and science to support biodiversity managers Poor agency and community awareness of dryland biodiversity and its protection needs

A first attempt to define a New Zealand Dryland Zone Area ~ 50,500 km 2 Rogers et all (2005) Science for Conservation. /documents/science-and- technical/SFC258.pdf

Dryland “Types” (including Manawatu) A. Gisborne-Hawke’s Bay This is the most northerly group of dryland environments. On average, they experience the most variable rainfall, the least severe and latest frosts, the highest winter and summer solar radiation, and the highest mean annual temperatures. C. Wairarapa – Wellington Coast – Nelson. Typically comprising young, fine sediments, often poorly-drained substrates with saline chemical limitations to forest growth, low atmospheric and soil moisture deficits. D. Coastal Marborough – Kaikoura Coast – inland North Canterbury The driest and sunniest dryland environment type, experiencing the highest atmospheric and soil moisture deficits and the highest average summer solar radiation. Soil fertility is generally high, and there are few chemical limitations to plant growth. H: Mackenzie Basin and Central Otago This group of environments covers the steeply sloping foothills of these basins, and is characterised by low atmospheric water deficts, low mean annual temperatures, low solar radiation inputs, and severe, early winter frosts, all reflecting southern latitude. Soils are often alluvial, and predominantly derived from schist. G: Inland southern south island basins and valley floors Complex of Nine groups, highly variable, cool, with v. variable moisture regimes and substrates. Most totara, fairly high notsol, 6.Mat & 7.Hall (share high with H), High Comp1 (share high with H), southerly, low mat, low junes, lwo decsol, highest jdgfrost, among earliersty fafrost, lowest rnvar, r2pet, among highest pendef (but low octvpd), high acidp, high sc (but not as high as h), among highest al, highest elev. B. North Island Hill Country Relatively moist (high rainfall: potential evapotranspiration ratio) environment with infertile soils, often derived from younger sedimentary rocks such as mudstones and siltstones. C. Wairarapa – Wellington Coast – Nelson - Manawatu Typically comprising young, fine sediments, often poorly drained substrates with saline chemical limitations to forest growth, low atmospheric and soil moisture deficits. D. Coastal Marborough – Kaikoura Coast – inland North Canterbury The driest and sunniest dryland environment type, experiencing the highest atmospheric and soil moisture deficits and the highest average summer solar radiation. Soil fertility is generally high, and there are few chemical limitations to plant growth. G: Inland southern South Island basins and valley floors This group of environments is highly variable, and distinguished by high elevation, severe frosts, low mean annual temperatures, low solar radiation inputs and relatively consistent annual rainfall. Soil moisture deficits are high, but atmospheric water deficts tend to be low. Soils are generally schist and alluvium derived and relatively fertile (with high acid-soluble phosphate). F: Canterbury Plains and Otago inland basin alluvium and loess These environments combine low temperatures and low solar radiation inputs, which reflect southern latitude, with characteristic alluvial and loessial substrates. E: Marlborough – North Canterbury The highest-elevation group of dryland environments, including relatively steeply sloping, well-drained foothills of the Marlborough and North Canterbury mountain ranges, characterised by high atmospheric moisture deficits. Older substrates predominate, and calcareous younger sedimentary rocks and older sedimentary rocks (e.g argillite) feature strongly. The Units we grouped into “Types” are (LENZ Lvl IV) land environments “Types” are defined based on environmental factors only (not plants and animals)

Area ~ 50,500 km 2 Dryland ecosystems have been extensively cleared TOTAL NZ LAND AREA REMAINING PREDOMINANTLY INDIGENOUS ECOSYSTEMS REST OF NZ 43.7% cleared 19.4% DRYLAND 83.4% cleared DRYLANDS

Area ~ 50,500 km 2 TOTAL NZ LAND AREA AREA LEGALLY PROTECTED (COVENANTS, DOC etc) REST OF NZ 38.1% protected 19.4% DRYLAND 2.4% protected DRYLANDS And have extremely poor protection

Area ~ 50,500 km 2 TOTAL NZ LAND AREA PROPORTION OF NZ’s MOST THREATENED PLANTS 19.4% DRYLAND 32.4% DRYLAND ACUTELY THREATENED PLANTS 41.7% DRYLAND CHRONICALLY THREATENED PLANTS But support high proportions of NZ’s most threatened plants, invertebrates and lizards NB lists & %s not updated to Townsend et al 2008/ de Lange et al 2009!!!

Area ~ 50,500 km 2 TOTAL NZ LAND AREA 19.4% DRYLAND DRYLANDS: 226 THREATENED PLANTS ALL of NZ: 1000 THREATENED PLANTS Acutely Threatened Chronically Threatened At Risk Facts & figures THREAT CATEGORIES ( PLANTS)

D. Coastal Marborough – Kaikoura Coast Driest and sunniest Highest air and soil moisture deficits High summer solar radiation Soil fertility generally high (alluvial) Drylands in the Nelson/ Marlborough patch C. Frosty northern lowland alluvium Relatively moist, with young, fine sediments, often poorly drained

E: Marlborough – North Canterbury hill country High elevation (inland, hilly) Steep slopes High air moisture deficits (nor’westers!) Limestone and argillite are geological features Drylands in the Nelson/ Marlborough patch G: Inland southern South Island basins and valley floors Highly variable, but distinguished by:  inland, so high elevation  cool, severe frosts, low solar radiation Big soil water deficits, BUT low air water deficits Fertile alluvium-derived soils

D. Coastal Marborough – Kaikoura Coast Driest and sunniest Highest air and soil moisture deficits High summer solar radiation Soil fertility generally high (alluvial)

E: Marlborough – North Canterbury hill country G: Inland southern South Island basins and valley floors

E: Marlborough – North Canterbury hill country …& down towards Nick Head’s patch…

All of NZ Drylands Acutely Threatened Chronically Threatened At Risk Critically Underprotected Underprotected No threat category

Threatened environments Combination of 3 national datasets Divides country into 6 threat categories based mainly on: past loss of indigenous vegetation (% indigenous cover left) but also on: current legal protection (% protected)

Threatened environments CategoryCategory CriteriaCategory Name 1<10% indigenous cover leftAcutely Threatened 210–20% leftChronically Threatened 320–30% leftAt Risk 4>30% left and <10% protected Critically Underprotected 5>30% left and 10–20% protected Underprotected 6>30% left and >20% protected Less Reduced and Better Protected No Data based on indigenous cover left, no matter how much protected based on indigenous cover left (>30%) left AND how much protected

Threatened Environment Classification Nelson-Marlborough Conservancy All Drylands only

Environment Threat Categories (Proportion Land Area) This Region’s Threatened Environments New Zealand Nelson-Marlborough Conservancy as a whole

Environment Threat Categories (Proportion Land Area) This Region’s Threatened Environments New Zealand Nelson-Marlborough DRYLANDS