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Within cities, vegetation along road corridors (variously referred to as nature strips, street verges or easements) can play a key role in providing habitat for wildlife and green space benefits for urban dwellers. In the city of Perth, Australia, many local government authorities (LGAs) now permit residents to convert the publicly owned land along the street in front of their dwelling from ‘traditional’ (yet exotic) turf to low growing, native gardens. ‘Verge gardens’ are perceived to require less water and better reflect a local sense of place by using plants endemic to the biodiversity hotspot in which Perth is situated. While interest in native verge gardens is growing rapidly within the community, there is relatively little supporting, spatially-based information for residents. The uncertainty of not knowing where to start is keenly felt by those residents for whom verge gardening is their first foray into gardening with native Western Australian plants in the sandy, nutrient-poor soils of Perth’s Swan Coastal Plain.Two LGAs in the city of Perth, Western Australia, were the focus of this research, both of which have deployed incentive programs to encourage residents to plant native verge gardens over many years. We conducted detailed semi-structured interviews and participatory verge garden mapping with 22 households who had converted their verges to native gardens over the last ten years, gauging residents’ views on verge gardening, nature, wildlife, community and sense of belonging. A small number of respondents were already highly knowledgeable on the topic of native plants before planting their gardens, while the majority of the respondents had increased their knowledge of native plants from a low initial level through the process of verge gardening. Verge gardens were mapped to highlight plant species diversity, age of garden and garden design style. Some residents had already drawn their own maps by hand, and shared these with us. Others kept detailed records of water usage, maintenance, plant growth and turnover, and insect and bird visitors to the gardens.A consistent theme that emerged from interviews with the majority of residents who claimed limited familiarity with native plants was a desire for more readily available information to help support their efforts. Information needs included: environmental data on soils, landforms, flora and fauna; knowledge of which plants would grow well in their soil type; where to source locally endemic plants; the most appropriate water and nutrient regime to care for the plants; and nearby examples of successful gardens from which to draw inspiration. Drawing on the results of interviews and participatory mapping, we present a prototype design for a public participatory mobile application that can provide geospatial and ecological information to help support residents, allow for initial planning and progressive micro-scale mapping of verge gardens, and provide the possibility for sharing information on exemplar gardens. Our research feeds into larger conversations among local-level policy makers and planners on urban greening, increasing social cohesion within suburban areas, and providing habitat for wildlife under conditions of environmental change and increasing population density.

Freshwater resources underpin multiple livelihood systems around the world, particularly in highly productive tropical floodplain regions. Sustaining Indigenous people’s access to freshwater resources for customary harvesting, while developing alternative livelihood strategies can be challenging. The sustainable livelihoods approach was applied to examine the ways in which multiple livelihoods in the East Alligator River floodplain region in northern Australia influence Aboriginal people’s access to freshwater resources for customary harvesting. Interviews with Aboriginal residents were conducted to understand changes to freshwater customary harvesting practices. The dominant floodplain-based livelihoods analysed were pastoralism, biodiversity conservation and tourism and they were found to generate both opportunities and constraints for sustaining freshwater customary harvesting. Opportunities were provided through facilitating regular access to floodplain country and opportunistic access for harvesting, which assists in sustaining bio-cultural knowledge. Partnerships developed through these mainstream livelihoods built human capacity that enhanced all livelihood resource capitals (natural, human, social, financial and physical). Three key ways the dominant livelihoods constrained access to key freshwater resources were identified. Tourism required sacrificing certain hunting places and had to accommodate recreational fishing pressure. The successful recovery of the saltwater crocodile population through biodiversity conservation policy has inadvertently reduced people’s customary access to in-stream resources. Pastoralism on the floodplain had restricted traditional floodplain burning practices associated with accessing aestivating long-necked turtles, affecting access and abundance. These findings highlight the need for the development of remote Indigenous livelihood strategies to make explicit their influences on freshwater customary harvesting practices, to better support their maintenance amongst multiple, non-customary floodplain livelihoods.

Land cover within eight drinking water catchments in Sarawak was classified into six categories using satellite imagery and GIS. The categories represented varying levels of vegetation modification from largely undisturbed or mature secondary vegetation (Category 1) through to bare, non-vegetated areas (Category 6). Rivers less than ∼10 m in width were usually ‘invisible’ on satellite images because of dense canopy cover. More than 70% of headwaters in all catchments, except one (Buri Bakong), were not visible, indicating the presence of dense riparian vegetation. For the river sections that were visible on satellite images, 5%–22% of the riparian buffer was highly degraded (completely lacking vegetation). The highest degree of riparian modification occurred in the lowlands, the midland catchment of Tingkas and the highland catchment of Trusan. Although Sarawak government policy requires buffer widths of 5–50 m of natural vegetation to be retained along all streams and rivers in drinking water supply catchments these guidelines were not met at nine of the eleven field sites surveyed. These results suggest that compliance with buffer guidelines is important to water quality in rivers, particularly in logging areas, oil palm plantations and near settlements.

The magpie goose is an iconic tropical species highly valued as a conservation asset and by Aboriginal people as a cultural resource. Most of the global population occurs in the Kakadu Region of northern Australia, which is at high risk from the combined impacts of invasive species and future sea-level rise. Future management responses require an increased understanding of their spatial and temporal dynamics and customary value. Historical aerial-survey data of geese and their nests in the Kakadu Region (1981–2006, 25 years) were used to characterise seasonal use of floodplains. Habitat ‘hotspots’ co-occurred with high abundance of plants that provide nesting material in the wet season and food in the dry season, particularly the bulbs of Eleocharis dulcis sedge. Goose numbers across the Northern Territory (1958–2000, n=42 years) exhibited 20-year decadal trends coupled with similar trends in rainfall and stream flow (1954–2006), which in turn were influenced strongly by global-scale interactions between the El Niño–Southern Oscillation and Pacific Decadal Oscillation. Stream flow drives the spatial and temporal dynamics of magpie geese at regional and decadal scales through its direct influence on floodplain-vegetation dynamics. Customary harvesting practices of geese and their eggs ascertained from interviews (2011–2014) showed that their cultural value extends beyond consumption, highlighting the need to address socio-ecological contexts in future management responses.

The internationally important river–floodplains of the Kakadu Region in northern Australia are at risk from invasive species and future sea-level rise–saltwater inundation (SLR–SWI), requiring assessments of multiple cumulative risks over different time frames. An integrated risk-assessment framework was developed to assess threats from feral animals and aquatic weeds at three SLR-scenario time frames (present-day, 2070 and 2100) to natural (magpie goose habitats), cultural (indigenous hunting–fishing sites) and economic (tourism revenue less invasive species control costs) values. Probability density functions (pdfs) were fitted to spatial data to characterise values and threats, and combined with Monte Carlo simulation and sensitivity analyses to account for uncertainties. All risks were integrated in a Bayesian belief network to undertake ‘what if’ management-scenario analyses, and incorporated known ecological interactions and uncertainties. Coastal landscapes and socio-ecological systems in the region will be very different by 2100 as a result of SLR; freshwater ecosystems will transform to marine-dominated ecosystems and cannot be managed back to analogue conditions. In this context, future invasive-species risks will decrease, reflecting substantial loss of freshwater habitats previously at risk and a reduction in the extent of invasive species, highlighting the importance of freshwater refugia for the survival of iconic species.

This paper describes a semi-quantitative approach for the assessment of sea-level rise (SLR) impacts on social–ecological systems (SES), using Yellow Water wetland on Kakadu National Park as a case study. The approach includes the application of a diagnostic framework to portray the existing SES configuration, including governance structures, in combination with qualitative modelling and Bayesian belief networks. Although SLR is predicted to cause saltwater inundation of freshwater ecosystems, cultural sites and built infrastructure, our study suggested that it may provide also an opportunity to bring together Indigenous and non-Indigenous knowledge and governance systems, towards a commonly perceived threat. Where feasible, mitigation actions such as levees may be required to manage local SLR impacts to protect important freshwater values. In contrast, adaptation will require strategies that facilitate participation by Kakadu Bininj (the Aboriginal people of Kakadu National Park) in research and monitoring programs that enhance understanding of salinity impacts and the adaptive capacity to respond to reasonably rapid, profound and irreversible future landscape-scale changes.