1 / 29

Urban areas as native habitat

Urban areas as native habitat. Outline. Why create native habitats in urban areas? Five principles to increase functioning native habitat & biodiversity. Why create urban habitats?. Scientific – biodiversity hotspots at environmental cross-roads, under-protected and vulnerable

ljoey
Download Presentation

Urban areas as native habitat

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Urban areas as native habitat

  2. Outline • Why create native habitats in urban areas? • Five principles to increase functioning native habitat & biodiversity

  3. Why create urban habitats? • Scientific – biodiversity hotspots at environmental cross-roads, under-protected and vulnerable • Social – create sense of place (most people live in cities and have limited ‘wild’ exposure) • Available resources – people and $ • It’s practical, do-able, often fits in with other uses and is more sustainable (resilient and cheaper in the medium term).

  4. Why not? – we’re in NZ, it’s easy to increase natives in cities… especially mobile species

  5. How are cities different? • Climate amplified • People but no grazing • Flattened topography • High weed pressures • High disturbance

  6. ‘Natural’ Ultic soils:old, famous • Teeming humus layers and shallow, nutrient-supplying topsoils, • Impoverished fertility • Structurally vulnerable; clay sediment runoff • Undisturbed: no surface casting fauna; low fire frequency

  7. City soils • Increased runoff & surface water flow: less infiltration, less storage, removal of watercourses, subsurface water flows cut • Stressed plants: shallow rooting, less oxygen and water, warmer damaged soil biota, mowing & removing leaves disrupts carbon cycling (N); elevated P (anti-myc), sometimes N

  8. Five principles • Tread gently – minimise impact & isolation • Bigger is often better – logs, area • Natives like natives - use native plants • Structurally complex, tall, dense is best • Plan for low maintenance & connectivity – minimise disturbance, connect water and organic cycles for resilient systems

  9. 2. Tread gentlyA. avoid, B. nurture, C. rehabilitate

  10. Bigger is often better Patch size (least edge) Canopy height Coarse wood

  11. Big patches – minimise edge

  12. Big wood for insects.. food and hiding places

  13. Big (untreated) wood for animals

  14. Big wood for little plants – epiphytes, refuges, fungae

  15. Big wood for erosion control

  16. Big wood for erosion control

  17. Structurally complex – tall & denseRichard Toft (Chch), Robin Gardner-Gee (Motuora) 1600 1400 1200 1000 Number of native beetles 800 600 400 200 0 Unmanaged A Planted A Pasture B

  18. Beetle assemblages in planted bush and unmanaged bush similar 20 Unmanaged bush 96 species 49 22 24 4 4 30

  19. Plan for low maintenance • Let sleeping logs (and leaves) lie • Weed removal at ground level (+ herbicide) • Natural water flows and connectivity minimise need for irrigation and drainage

  20. No dense, long-lived weedmat

  21. How to heal soil • Loosen – let air in • Avoid traffic, especially when wet • Maximise plant growth and cover (avoid direct rain drop contact – erosion) • Use organic mulches • Connect leaves and invertebrates to humus and soil

  22. Removing litter and topsoil reduces growth; soil recovers slowly 100 4 year-old trees 15 year-old trees 80 60 Tree volume (% of control) 40 20 0 Topsoil removed Litter removed Control Treatment

  23. Plants need water & organic matter… so connect flows

  24. What about exotics?

  25. We have the colours

  26. We have toughness

  27. Principles • Tread gently – minimise impact & isolation • Bigger is better – logs, area • Natives like natives • Structurally complex is best • Plan for low maintenance & connectivity (water and leaf litter)

  28. Fabulous free NZ resources • www.doc.nz/regional-info/010Canterbury/005Publications/ • Protecting-and-Restoring-Our-Natural-Heritage • www.bush.org.nz/planterguide • www.landcareresearch.co.nz • Hewitt 2004 ‘Soil Properties for plant growth’

More Related