Adoption of erosion management practices in New Zealand

- Rainfall, wind and temperature influence the adoption of management practices.
- Pugging of land in heavy stock grazing areas determines adoption of tree planting.
- Complementarity exists between water and sediment management practices.
- Complementarity exists between sediment management and land retirement.
- Water sources (surface, ground or rainfall) influence the adoption of different practices.

Soil erosion is a serious environmental threat to New Zealand's agricultural sector. Economic costs of soil erosion are significant and the costs of adopting mitigation and management practices, given the targets set by environmetal policy, do not spread uniformly across space, economic activities and types of erosion processes. Management practices have been widely employed by farmers and promoted by several policy programs. Practices are not mutually exclusive and could be jointly adopted by comparing productivity gains against costs of implementation. However, research on the identification of the drivers of adoption is scarce in New Zealand. To identify the determinants of adoption of management practices in New Zealand farms, we combine novel survey information with data on climate and erosion in a multivariate probit framework. This framework allows identification of potential complementarity or substitution between management practices. We find significant and heterogeneous effects from erosion levels, temperature, wind velocity and primary land uses on the adoption of any of the practices. In addition, we also find significant complementarities between management practices. The results of this study are important because the complementarities relate to external effects of erosion mitigation which can help to promote public acceptability of mitigation policies.