Regenerative agriculture in Aotearoa New Zealand - research pathways to build science-based evidence and national narratives.

fals

Attitudes of a farming community towards urban growth and rural fragmentation – An Auckland case study

As the global population continues to increase, rural areas are expected to accommodate future growth at the same time as continuing to feed growing populations. This tension is greatest on those who farm land that is earmarked for future urban growth. Yet, little is known about the attitudes and values of the affected rural farming communities or farmers’ perceptions of the challenges and opportunities that population growth presents. This paper presents the results from a survey of outdoor vegetable growers in Pukekohe, an area under increasing pressure from urban growth, located in Auckland, New Zealand’s fastest growing city. An analysis of rural fragmentation is also provided to demonstrate the extent of land use change to help contextualise growers’ responses. Survey results showed that economic discourses fail to fully capture the symbolic meaning the land has for growers; many participants were deeply connected to the land, with the desire for the farming legacy to continue, while also recognising its highly productive capability. Participating growers identified numerous challenges and opportunities as a consequence of urban growth. Key challenges included: reverse sensitivity associated with development pressures; achieving sustainable productivity and profits; and perceptions of an increasingly bureaucratic legislative environment. Key opportunities included: occupation of a unique vegetable growing environment; capitalising on the area’s close proximity to city markets; and for a minority of participants, possible financial gains through residential housing development. Geospatial analysis demonstrated a large degree of rural fragmentation that can lead to adverse cumulative effects without the intervention of policy. Future research needs to focus on determining the consequences of continuous development pressures onto versatile land in relation to a country’s, current and future, food-growing capacity. This will be imperative as the population continues to grow. It will not only inform the environmental impacts of these land use decisions but also the socio-economic consequences that will aid with fully informed planning, policy and decision-making that account for a multiplicity of needs.fals

Bacteria as emerging indicators of soil condition

Bacterial communities are important for the health and productivity of soil ecosystems and have great potential as novel indicators of environmental perturbations. To assess how they are affected by anthropogenic activity and to determine their ability to provide alternative metrics of environmental health, we sought to define which soil variables bacteria respond to across multiple soil types and land uses. We determined, through 16S rRNA gene amplicon sequencing, the composition of bacterial communities in soil samples from 110 natural or human-impacted sites, located up to 300 km apart. Overall, soil bacterial communities varied more in response to changing soil environments than in response to changes in climate or increasing geographic distance. We identified strong correlations between the relative abundances of members of Pirellulaceae and soil pH, members of Gaiellaceae and carbon-to-nitrogen ratios, members of Bradyrhizobium and the levels of Olsen P (a measure of plant available phosphorus), and members of Chitinophagaceae and aluminum concentrations. These relationships between specific soil attributes and individual soil taxa not only highlight ecological characteristics of these organisms but also demonstrate the ability of key bacterial taxonomic groups to reflect the impact of specific anthropogenic activities, even in comparisons of samples across large geographic areas and diverse soil types. Overall, we provide strong evidence that there is scope to use relative taxon abundances as biological indicators of soil conditio

Land use modification causes slow, but predictable, change in soil microbial community composition and functional potential

Abstract Background Bacterial communities are critical to ecosystem functioning and sensitive to their surrounding physiochemical environment. However, the impact of land use change on microbial communities remains understudied. We used 16S rRNA gene amplicon sequencing and shotgun metagenomics to assess soil microbial communities' taxonomic and functional responses to land use change. We compared data from long-term grassland, exotic forest and horticulture reference sites to data from sites that transitioned from (i) Grassland to exotic forest or horticulture and from (ii) Exotic forest to grassland. Results Community taxonomic and functional profiles of the transitional sites significantly differed from those within reference sites representing both their historic and current land uses (P < 0.001). The bacterial communities in sites that transitioned more recently were compositionally more similar to those representing their historic land uses. In contrast, the composition of communities from sites exposed to older conversion events had shifted towards the compositions at reference sites representing their current land use. Conclusions Our study indicates that microbial communities respond in a somewhat predictable way after a land use conversion event by shifting from communities reflecting their former land use towards those reflecting their current land use. Our findings help us to better understand the legacy effects of land use change on soil microbial communities and implications for their role in soil health and ecosystem functioning. Understanding the responsiveness of microbial communities to environmental disturbances will aid us in incorporating biotic variables into soil health monitoring techniques in the future