Whangarei District natural hazard constraints report Technical Report
- Author
- Coleman, D.
- Year
- 2009
- Publisher / Organisation
- Whangarei District Council
- Summary
- Ecosystem services refer to the many goods and services emanating from the functioning of the local environment. People benefit from many different ecological functions, from water purification services within water bodies to wild pollination. Many of these services are simply by-products of natural processes and functions happening within ecosystems, but as environmental pressures increase, greater cognisance is been taken globally of the benefits derived from these historically ?free' services. Planning for ecosystem service delivery tries to ensure that the tradeoffs between the provision of different ecosystem services are worthwhile, in that oversupply of one service does not lead to the undersupply of another. Taking an ecosystem services delivery approach expands the focus beyond understanding how development affects ecosystems, but also includes understanding how development is dependant on ecosystem services. The delivery of many ecosystem services requires well-functioning ecosystems, and this includes major contributions from biological diversity. Some ecosystem functions and subsequent services are produced by single species, whereas others are the result of a larger number of species such as in the case of freshwater quality. Ecosystem services are sourced from a variety of landscapes, including both rural and urban lands, developed or undeveloped. However, the way the resources are managed has an impact on the delivery and quality of those ecosystem services. The key areas of interest in terms of ecosystem services and future development would be: provisioning services such as food (dairying, pastoral, horticulture), fibre (timber), freshwater (drinking and potential irrigation), air quality regulation (around urban areas), local climate regulation (especially in urban areas), global climate regulation, water regulation (especially run-off, flooding, and aquifer recharge), erosion regulation, water purification and waste treatment (especially around settlements), pest regulation, pollination, natural hazard regulation (reducing damage from natural hazard events such as storms, or retaining enough moisture to avoid fire risk), recreation and ecotourism elements, nutrient cycling (efficiency of soil micro-organisms in processing and making available nutrients), and soil formation. In general terms, habitats of larger sizes will supply more ecosystem services than modified landscapes of a similar size. However, modified landscapes will supply ecosystem services as well, irrespective of whether it is forestry, pastoral landscape or dairying, and these areas will often supply more than urban areas. The supply of ecosystem services from lifestyle blocks is heavily dependant upon their management, and cannot easily be generalised Therefore fragmentation of these areas is especially important to understand how ecosystem services may be impacted by future development, especially within catchments. 6 Few significant natural areas are directly located within the projected areas for growth under any of the Three Futures. However, some significant natural areas are generally located with settlement catchment boundaries, and these will be supplying a range of ecosystem services that settlements are dependand upon. The main concern in terms of Future One is that ongoing popularity of versatile soils for lifestyle blocks does put pressure on ecosystem services. As these areas are developed, pressure for food production, and reverse sensitivity in remaining productive blocks close to the lifestyle property owners, will mean that present marginal areas will come under pressure. Future Two is the most neutral in regards to the overall delivery of ecosystem services, due to less pressure for lifestyle opportunities in rural areas, and a smaller distributed population in coastal areas compared with Future One. However, Future Two, with its very large focus on Ruakaka/Marsden, is the future most reliant on restoring and maintaining ecosystem services, especially in terms of the upper catchments serving Ruakaka/Marsden Point. Future Three has the least impact on the delivery of ecosystem services over a wide range of services. However, compared with Future One, it may not necessarily provide the delivery of services reliant on restoration of indigenous vegetation. More concentrated settlement patterns will mean that more attention is required within these catchments to ensure that the requisite delivery of ecosystem services is available and does not impact on individual's and community's well-being.