(Section 20 of the RPS)

The Northland region contains a variety of landforms, soil types and associated land uses. Its landforms range from young active sand dunes along the coasts to relatively old greywacke, and volcanic peaks and hills in inland areas. One of the notable features of the region is that it has few high mountain ranges with no area being more than 800 metres above sea level. It also has few large areas of flat, low lying land, the most significant lowlands being adjacent to the Awanui and Northern Wairoa Rivers.

The soils in the region vary considerably in structure and origin, ranging from those which are poorly drained and relatively infertile e.g. gum land soils, to those which are free draining and fertile, primarily of alluvial or volcanic origin. Over 100 different soil types have been identified. Much of this land was clothed in forest before large scale deforestation exposed the soil to erosion with off-site effects of flooding, siltation and alteration of the low flow regimes of rivers.

Under the RMA, both the NRC and district councils have land management responsibilities. The NRC's responsibilities are fairly specific, relating primarily to soil conservation, mitigation of natural hazards, control of contaminant discharges and associated water quality management. However, it also has a general overview role in terms of identifying and setting policy in relation to any effects of the use, development or protection of land which are of regional significance. The district council's are responsible for managing effects of the subdivision of land and associated land use activities in terms of their location, servicing, effects on natural features and other amenities.

Anticipated Outcomes

· Continued availability of highly versatile soils for primary production.

· Reduction in the damage caused to soils and natural features from pests and noxious plants.

· Safer use, storage and disposal of pesticides and other agricultural chemicals and reduced risk of soil contamination.

· More widespread adoption of soil conservation practices within land use and subdivision proposals.

· Reduction of erosion in high risk areas.

· Reduction in the volumes of soil and other contaminants entering surface water bodies.

Policy Mix

The objectives for the soil conservation and land management section are:

· maintenance, and where possible, enhancement of life supporting capacity of soils;

· protection of soil resources, including soil quality and quantity, from degradation or loss;

· safeguarding the life-supporting capacity of water and ecosystems;

· avoidance, remedying or mitigation of the adverse effects of plant and animal pest on the use of land.

The policy approach for soil conservation and erosion control (Policy 20.4 (a)) is a combination of educative and regulatory measures. The approach is based on the use of best management practices.

The policy approach for contaminant discharges (Policy 20.4 (b)) is to increase public awareness of application procedures along with monitoring and control of disposal operations. Discharges of potentially toxic contaminants are strictly controlled.

The protection of highly productive and versatile soils (Policy 20.4 (c)) is approached by identifying such soils and regulating the effects of subdivision and use on highly productive and versatile soils.

The control of plant and animal pests (Policy 20.4 (d)) section is approached from a regulatory and operational focus. Pest management strategies are highlighted as well as pest control programmes.

The Soil Conservation and Land Management section contains 19 individual methods of implementation that flow from the policy direction discussed above.

What's the current state?

Land use change has had the greatest effect on soil health and the extent of erosion. Unsuitable land management practices can place significant pressures on soil health. Stock overgrazing and increased stocking densities on farms increases the potential for soil compaction, pugging and erosion. The most widespread form of erosion on pastoral land in Northland is gully erosion. Sheet erosion is also common throughout the region.

Information on soil types, geology, slope and drainage has been used for classifying land in the Northland region. The New Zealand Land Resources Inventory (NZLRI) assesses capability based on eight land use capability classes.

Remaining natural habitat areas are small and fragmented. This increases the pressures from surrounding land uses. Approximately 22% of the Northland region remains in indigenous forest. Only 5% of the original coastal/freshwater wetlands remain.

Exotic forestry now occupies approximately 10% of the region, and has positive effects on soil stability and subsequent water quality when the trees are growing and fully established. However, soils can be adversely affected during harvesting and planting.

Only approximately 10% of Northland's soil is classified as ‘highly productive and versatile' (classes 1, 2, or 3). In recent years, large areas of land in Northland with prime soils for agricultural and horticultural land use have been subdivided into lifestyle blocks and for urban development. In most cases this renders it unavailable for sustainable horticultural and agricultural land uses. This is obvious in the areas of Maunu, Kamo and Glenbervie in Whangarei and around Kerikeri in the Far North. Approximately 9% of Northland's prime soils have been subdivided into 2,209 lots over the last six years, with an average lot size of about two hectares. This is based on resource consent data for land subdivision from Whangarei (January 2001 to October 2006), Far North (June 2002 to February 2007), and Kaipara (up to July 2005) districts.

Macroporosity (the larger spaces within the soil where water can go) had decreased for many sites (due to compaction of soil), particularly at dairy and dry stock pastoral sites, which is generally a result of intensification of these land use practices. This can result in more flooding and pugging because rainwater runs off the land quicker. Mineralisable nitrogen values were also significantly lower at most sites in 2007 compared to 2001. Otherwise there were few changes consistent across land uses.

Overall, the majority of instances of poor soil quality could be reversed by appropriate management. Landcare Research has recommended that sampling should continue to determine the extent and direction of any long term changes in soil quality. They also recommend increasing the number of sites, to gain more representative sites for each different land use and to sample different soil types.

What has worked well in this section?

The focus on integrated catchment management is growing with more and more initiatives being undertaken at the catchment level. The value of wetlands and riparian planting for erosion control are being recognised and provided for. Community land management programmes are working well.

What has not worked in this section?

There has been continued loss of high quality and versatile soils to non-productive uses. Maps of high value and versatile soils have not been placed into the RPS and this part of the section has not been implemented.

Run-off from earthworks and changes in land use is continuing to cause erosion and contamination of water ways. Large scale earthworks should not be approved independently of the land use consent and vice versa. Concern has been expressed at the different approaches to earthworks between district plans and the Water and Soil Plan. This section of the RPS could provide more guidance and ensure consistency for the management of earthworks across the region.

General comments on this section:

There is a need to ensure this section is integrated with other sections of the RPS, including the Waste Management section and Water Quality and with other relevant documents including the regional pest management strategies.

There is no monitoring of permitted activity rules and it is therefore not possible to comment on their effectiveness. However, there is concern that the cumulative impact of permitted activities may be having a more than minor adverse effect on the environment. This is considered one of the areas where increased monitoring effort is required to ensure an appropriate management regime is implemented through the regional plans.

Is this section Efficient and Effective?

There is a need to prioritise areas for soil conservation and also deal with the associated problems caused by landowners not acknowledging erosion problems and effects. There should be more active promotion of the benefits and outcomes of ‘retiring land'. More resources are being developed – particularly in the areas of land care and providing technical expertise. There is a need for current information on soil loss rates on a catchment basis in order to identify priority areas.

The NRC holds data on versatile soils. The Environment Court has released a number of cases on versatile soils, essentially saying that they should not receive primacy, but should be considered in the overall framework of sustainable management. The RPS requires the district councils to identify versatile soils in their district plans. The provisions should be targeted towards appropriate land-use strategies, rather than just concentrating on versatile soils.

While many methods are being implemented, there is a real need to increase co-ordination, communication and consistency with other agencies involved in managing Northland's land resource, particularly district councils and the Department of Conservation, and with industry groups such as Fonterra and forestry companies.

Emerging Issues for this section?

Over the past 10 years there has been a significant change in land use and intensification of land use within many catchments. While in general terms the effect of these changes in land use is known and understood, in many cases the current management regime does not provide sufficient guidance or is too weak to effectively manage this change. Often changes in land use are guided by development pressure rather than strategic planning, where planning documents have struggled to keep pace with development. The RPS should strengthen provisions towards providing clear and concise region wide direction as to appropriate land use activities at a specific level. The RPS should also consider appropriate tools to encourage the preferred use of land (particularly highly productive and versatile soils) such as economic incentives and discouragement of subdivision.

A key aspect to providing an efficient and effective management regime is having supporting monitoring information. Sediment source tracking has been identified as a key area where improved monitoring is required to enable the development of a more targeted management regime.

The cumulative effects of multiple land use activities are difficult to monitor and manage. There is a growing concern that the range of permitted activities within Northland's planning documents may have a ‘more than minor' adverse effect on the environment.

New pest and animal threats are emerging due to climate change. The focus of pest management is moving towards integrated community driven pest control operations, inter-agency collaboration and a site led approach. This section of the RPS could be changed to reflect this focus.

Conclusion

Land management and soil conservation may be an area that the RPS needs to prioritise and provide stronger guidance around in the future. Appropriate management of land use activities is critical to the efficient and effective management of Northland's natural and physical resources. A more coordinated approach to land management and soil conservation between local authorities coupled with a refocused monitoring effort will be necessary to support a more directive land management regime.