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New Zealand’s apiculture industry is the fastest growing in the world, expanding in agricultural landscapes, as well as in native ecosystems. While this has obvious benefits for economy and industry, the impacts on sustainability of native ecosystems are less easy to discern. Honey bees (Apis mellifera) have a suite of potential impacts, both positive and negative, on native plants and flower visitors in native ecosystems. This research aimed to investigate the impact of managed introductions of Apis mellifera in native forest dominated by Weinmannia racemosa and Ixerba brexioides, two native forest trees used extensively for monofloral honey production in New Zealand. Research focused on three key areas: 1) timing and availability of floral nectar resources; 2) impacts on plants, particularly I. brexioides and W. racemosa; and 3) impacts on invertebrate flower visitor communities. Availability of floral nectar resources from I. brexioides and W. racemosa was assessed using a combination of nectar collection and phenology data. Pollination potential of honey bees was assessed using video surveillance and effects on seed set of I. brexioides and W. racemosa were observed using exclusion experiments. Community-level effects on invertebrate flower visitors were assessed using collection of flower visitors and assessment of community data using multivariate and other statistical approaches. Timing and availability of floral nectar resource showed extreme variation between annual cycles. Nectar sugar production was lowest during a hot, dry summer compared with a cooler, wetter summer, in terms of both sugar production per flower and flower production per tree. At a landscape scale, this can have serious flow-on effects for foraging nectar-feeders, and hence for seed set of flowering plants. Video surveillance showed that suitability of different flower visitors for pollination of I. brexioides and W. racemosa differed. For W. racemosa all groups of flower visitors contac

Ecosystems worldwide are being degraded and destroyed by human actions on an unprecedented level. This continues despite growing evidence that intact, functioning ecosystems are critical to human health and well-being. The field of restoration ecology has rapidly developed as a response to ameliorate the damage by investigating how to re-build ecosystems. This branch of science generally posits that replacing lost structure, i.e. re-vegetation, will re-create ecosystems, but there is little empirical evidence supporting this assumption. In ecosystems with long development timelines, such as forests, it is unclear how dynamics change after planting and over the long-term, and hence what best management practices should be used in the decades following initial plantings. This thesis addresses these knowledge gaps through three separate studies on restored urban forests. The first study investigated whether planted trees will eventually grow into self-regenerating forests that provide suitable conditions for establishment of late-successional plant species. Further, what timeline does this occur along and what specific conditions drive native plant regeneration? To answer these questions a chronosequence of restored urban temperate rainforests aged 3 to 70 years was used in the New Zealand cities of Hamilton and New Plymouth. Various ecosystem properties were measured in the restored forests and compared with the same in remnant and unrestored forests. Structural equation modelling was used to determine which properties were significant drivers of plant regeneration and break point analysis was used to identify thresholds in ecosystem property development over time. Results indicated that unrestored forests had marginally fewer regenerating late-successional plants than remnant forests did. This indicates that restoration actions must take place in these areas to ensure regeneration densities reach natural, desirable levels. The final model indicated it is possible for

Urban forest patches have unique environmental and landscape characteristics which may influence the restoration of native plant communities. Urbanisation can lead to a drier and warmer climate, a prevalence of exotic seed sources and isolation from remnant native forest seed sources. This research investigates how these factors influence native species presence in different aged urban forest patches and uses life history traits to identify vulnerable species groups which may require active reintroduction. Seed rain, soil seed banks and vegetation composition was recorded within urban forest restoration plantings (10-36 years old) in Hamilton City, New Zealand with comparison to naturally regenerating forest within the city and a nearby rural forest remnant. To address dispersal limitation for several key mid to late successional forest species an experiment was also undertaken to investigate broadcast seeding as a method to reintroduce trees with large seeds and fleshy fruits into established early successional vegetation. Seed rain, soil seed banks (fern spores inclusive) and understorey vegetation in urban forest were found to have higher exotic species richness and lower native species density and richness than rural forest. Both understorey vegetation and soil seed banks of urban sites >20 years old had lower exotic species richness than younger (10–20 years) sites, indicating a developmental threshold that provided some resistance to exotic species establishment. A prevalence of exotic species in urban seed rain, however, will allow reinvasion through edge habitat and following any disturbance to canopy vegetation. Persistent soil seed banks from both urban and rural sites were dominated by exotic herbaceous species and native fern species, while few other native forest species were found to persist for >1 year in the seed bank. Urban native seed rain was greater in quantity than exotic seed rain (reflecting immediately surrounding vegetation) although only wh

Ecological compensation is commonly employed but rarely evaluated around the world. In order to assess application of the tool in New Zealand, a systematic nationwide review was undertaken. The research used a combination of qualitative and quantitative tools (i.e. a mixed methods approach) to investigate outcomes associated with ecological compensation under the Resource Management Act 1991 and how variation among outcomes might be explained. Three key research components were addressed: compliance, practice and stakeholder perspectives. Compliance The levels of regulatory compliance were assessed in 81 consents and 245 conditions with an overall compliance level of 64.8%. Public organisations (75.5%) were more likely to comply than private companies (65.5%), followed by private individuals (54.7%). Administrative conditions (paper-based) were much more likely to be complied with (82.6%) than non-administrative (action based) conditions (49.6%). There were significant differences in compliance rates across different activities from Agriculture (4.8%) through to Energy Generation (100%), demonstrating the importance of understanding the nature of non-compliance in improving regulatory compliance and enforcement. Practice The recognition of key implementation issues of ecological compensation were investigated based on the ecological exchanges approved in 110 consents. The key implementation issues were (1) equivalency, (2) spatial proximity, (3) additionality, (4) timing, (5) duration and compliance, and (6) currencies and ratios. Most exchanges approved under the RMA were ‘in-kind’ (i.e. broadly similar in type) but that their ecological equivalence was difficult to determine due to poor information. Most exchanges were close to the site of impact (65.5%), and those at a distance were typically the result of aggregated schemes such as mitigation trusts. Most requirements for ecological compensation can be considered to be additional, as there are few other means of