School of Geography, Earth and Atmospheric Sciences - Research Publications
Permanent URI for this collection
Search Results
1 - 10 of 17
-
ItemNo Preview AvailableReconciling oil palm and ecosystems(NATURE PORTFOLIO, 2023-05)
-
ItemRising floodwaters: mapping impacts and perceptions of flooding in Indonesian Borneo(IOP Publishing Ltd, 2016-06)The roles of forest and wetland ecosystems in regulating flooding have drawn increasing attention in the contexts of climate change adaptation and disaster risk reduction. However, data on floods are scarce in many of the countries where people are most exposed and vulnerable to their impacts. Here, our separate analyses of village interview surveys (364 villages) and news archives (16 sources) show that floods have major impacts on lives and livelihoods in Indonesian Borneo, and flooding risks are associated with features of the local climate and landscape, particularly land uses that have seen rapid expansions over the past 30 years. In contrast with government assessments, we find that flooding is far more widespread, and that frequent, local, events can have large cumulative impacts. Over three years, local news agencies reported floods that affected 868 settlements, 966 times (including 89 in urban areas), inundated at least 197 000 houses, and displaced more than 776 000 people, possibly as many as 1.5 million (i.e. 5%-10% of the total population). Spatial analyses based on surveys in 364 villages show that flood frequency is associated with land use in catchment areas, including forest cover and condition, and the area of wetlands, mines (open-cut coal or gold mines), and oil palm. The probability that floods have become more frequent over the past 30 years was higher for villages closer to mines, and in watersheds with more extensive oil palm, but lower in watersheds with greater cover of selectively-logged or intact forests. We demonstrate that in data-poor regions, multiple sources of information can be integrated to gain insights into the hydrological services provided by forest and wetland ecosystems, and motivate more comprehensive assessment of flooding risks and options for ecosystem-based adaptation.
-
ItemThe impacts of land use change on flood protection services among multiple beneficiaries(ELSEVIER, 2022-02-01)Land use change drives significant declines in ecosystem services globally. However, we currently lack an understanding of how and where different beneficiaries of ecosystem services experience the impacts of land use change. This information is needed to identify possible inequalities in the delivery among beneficiaries, and to design policy interventions to address them. Here, we used a spatially explicit and disaggregated approach to ask how land use change affects the distribution of flood protection among three beneficiary sectors (urban residents, rural communities, and the food sector). Our study focused on the Brigalow Belt Bioregion of Australia - an area affected by widespread deforestation - and assessed the effect of land use change on flood protection between 2002 and 2015. We estimated flood protection per beneficiary sector as the total upstream runoff retention (supply) linked to areas where flood protection is required for sector-specific infrastructure (demand). We calculated changes in flood protection between 2002 and 2015 at the local government area scale and for each beneficiary sector. Using counterfactual scenarios, we identified whether changes in flood protection were driven by forest loss or changes in the extent of infrastructure at risk of flooding. We found net declines in flood protection for all sectors. Urban residents experienced the greatest decline (28%), followed by rural communities (15%), and the food sector (14%). Overall declines in flood protection across the whole region were driven primarily by forest loss. However, for some local government areas and beneficiaries, changes in flood protection were also driven by increases in forest cover or spatial changes in demand. Recognition that beneficiary sectors can be impacted via different drivers of change is fundamental to revealing highly impacted sectors. In turn, this information can be used to develop management strategies to address inequalities in the distribution of ecosystem services among beneficiaries.
-
ItemEnhancing feasibility: Incorporating a socio-ecological systems framework into restoration planning(ELSEVIER SCI LTD, 2016-10)Forest restoration is the counterforce to deforestation. In many parts of the world it mitigates forest loss and degradation, but success rates vary. Socio-political variables are important predictors of effectiveness of restoration activities, indicating that restoration strategies need to be locally adapted. Yet, contextual assessments of the biophysical, social and political characteristics of forest restoration are rare. Here, we integrate a social-ecological systems framework with systematic decision-making to inform forest restoration planning. We illustrate this approach through a prioritization analysis in a community-based forest restoration context in Paser District, East Kalimantan, Indonesia. We compare the solutions of our integrated framework with those identified on the basis of biophysical criteria alone. We discover that incorporating a socio-political context alters the selection of priority areas. While the social feasibility and political permissibility can be enhanced, ecological benefits are likely to be reduced and/or opportunity costs of alternative land uses are to be increased. Our conceptual framework allows the appraisal of potential trade-offs between social and ecological outcomes of alternative options, and has the potential to evaluate the efficiency of existing policies. Empirical testing in a range of contexts is required to ensure broad applicability and transferability of our conceptual framework.
-
ItemNo Preview AvailableGlobal Demand for Natural Resources EliminatedMore Than 100,000 Bornean Orangutans(CELL PRESS, 2018-03-05)Unsustainable exploitation of natural resources is increasingly affecting the highly biodiverse tropics [1, 2]. Although rapid developments in remote sensing technology have permitted more precise estimates of land-cover change over large spatial scales [3-5], our knowledge about the effects of these changes on wildlife is much more sparse [6, 7]. Here we use field survey data, predictive density distribution modeling, and remote sensing to investigate the impact of resource use and land-use changes on the density distribution of Bornean orangutans (Pongo pygmaeus). Our models indicate that between 1999 and 2015, half of the orangutan population was affected by logging, deforestation, or industrialized plantations. Although land clearance caused the most dramatic rates of decline, it accounted for only a small proportion of the total loss. A much larger number of orangutans were lost in selectively logged and primary forests, where rates of decline were less precipitous, but where far more orangutans are found. This suggests that further drivers, independent of land-use change, contribute to orangutan loss. This finding is consistent with studies reporting hunting as a major cause in orangutan decline [8-10]. Our predictions of orangutan abundance loss across Borneo suggest that the population decreased by more than 100,000 individuals, corroborating recent estimates of decline [11]. Practical solutions to prevent future orangutan decline can only be realized by addressing its complex causes in a holistic manner across political and societal sectors, such as in land-use planning, resource exploitation, infrastructure development, and education, and by increasing long-term sustainability [12]. VIDEO ABSTRACT.
-
ItemImpacts of tropical deforestation on local temperature and human wellbeing perceptions(ELSEVIER SCI LTD, 2018-09-01)The combined effects of changes in climate and land cover expose millions of people to an increased likelihood of heat illness. Impacts of heat stress on health have primarily been quantified for urban environments, particularly in developed countries. Far less is known in other settings, including the effects of ongoing tropical deforestation on local temperature and its consequences for people living in these rapidly changing landscapes. Here, we explore links between deforestation and self-reported human health and well-being in the tropical landscapes of Borneo. We use extensive social surveys from nearly 500 villages throughout Kalimantan (Indonesian Borneo) that asked whether forests were important for health, and why. The most frequent answer viewed forests as important for maintaining cool local temperatures (volunteered by 28% of 4634 respondents). Using boosted regression tree analysis incorporating spatial metrics of deforestation and temperature, we found that villagers were more likely to report this cooling effect if they were from villages with higher or more variable temperatures, and in recently deforested or fragmented landscapes. Our results highlight the role of forests in regulating the local climate. This ecosystem service is highly threatened, and yet increasingly vital for avoiding heat illness and enabling adaptation to global climate change.
-
ItemAusTraits, a curated plant trait database for the Australian flora(NATURE PORTFOLIO, 2021-09-30)We introduce the AusTraits database - a compilation of values of plant traits for taxa in the Australian flora (hereafter AusTraits). AusTraits synthesises data on 448 traits across 28,640 taxa from field campaigns, published literature, taxonomic monographs, and individual taxon descriptions. Traits vary in scope from physiological measures of performance (e.g. photosynthetic gas exchange, water-use efficiency) to morphological attributes (e.g. leaf area, seed mass, plant height) which link to aspects of ecological variation. AusTraits contains curated and harmonised individual- and species-level measurements coupled to, where available, contextual information on site properties and experimental conditions. This article provides information on version 3.0.2 of AusTraits which contains data for 997,808 trait-by-taxon combinations. We envision AusTraits as an ongoing collaborative initiative for easily archiving and sharing trait data, which also provides a template for other national or regional initiatives globally to fill persistent gaps in trait knowledge.
-
ItemSeedling diversity in actively and passively restored tropical forest understories(WILEY, 2021-04)Alternative methods for restoring tropical forests influence the ecological processes that shape recruitment of understory species. In turn, the traits of species recruited will influence the ecological processes the forests provide now and over the long term. We assess the phylogenetic and functional structure of seedlings beneath monoculture plantations, mixed-species plantations (both active restoration) and regenerating selectively logged native forests (passive restoration), considering traits of specific leaf area (SLA, including within-species variation), leaf nitrogen and phosphorus content, life-form, potential plant height, and dispersal type. Monoculture plantations comprised seedlings that were more closely related then would be expected by chance (i.e., phylogenetically clustered), and regenerating forest contained species more distantly related then would be expected by chance (i.e., phylogenetically overdispersed). This suggests that seedlings beneath monocultures assemble through environmental filtering and through the dispersal limitation of predictable functional guilds. However, dispersal limitation is frequently overcome by human-assisted dispersal, increasing trait diversity. Comparing SLA values revealed that regenerating forests recruit seedlings with both high and low mean and variation of SLA, leading to higher overall diversity. Regenerating forest seedlings showed signs of environmental filtering, only based on within-species variation of SLA. Regenerating forest understories appear to favor species that show a high intraspecific variation in SLA values (e.g., Pterocarpus indicus Willd.) and at the same time provided habitat for later successional seedlings that show a lower intraspecific variation in SLA (e.g., Canarium luzonicum (Blume) A.Gray). This trait diversity suggests limiting similarity or competitive exclusion may be reduced because of niche differences, allowing species with different traits to coexist. Phylogenetic and functionally distinct species are restricted in their regeneration capacity, many of which are of conservation significance (under the IUCN Red List). Reforestation projects should maximize desired ecological services (including conservation value) by actively managing for the recruitment of species that are phylogenetically and functionally (including intraspecifically) distinct. This management aim will increase the probability of fulfilling a wider array of niche spaces and potentially increase the diversity of ecosystem services provided.
-
ItemIt's Not Just Conflict That Motivates Killing of Orangutans(PUBLIC LIBRARY SCIENCE, 2013-10-09)We investigated why orangutans are being killed in Kalimantan, Indonesia, and the role of conflict in these killings. Based on an analysis of interview data from over 5,000 respondents in over 450 villages, we also assessed the socio-ecological factors associated with conflict and non-conflict killings. Most respondents never kill orangutans. Those who reported having personally killed an orangutan primarily did so for non-conflict reasons; for example, 56% of these respondents said that the reason they had killed an orangutan was to eat it. Of the conflict-related reasons for killing, the most common reasons orangutans were killed was fear of orangutans or in self-defence. A similar pattern was evident among reports of orangutan killing by other people in the villages. Regression analyses indicated that religion and the percentage of intact forest around villages were the strongest socio-ecological predictors of whether orangutans were killed for conflict or non-conflict related reasons. Our data indicate that between 44,170 and 66,570 orangutans were killed in Kalimantan within the respondents' active hunting lifetimes: between 12,690 and 29,024 for conflict reasons (95%CI) and between 26,361 and 41,688 for non-conflict reasons (95% CI). These findings confirm that habitat protection alone will not ensure the survival of orangutans in Indonesian Borneo, and that effective reduction of orangutan killings is urgently needed.
-
ItemEffectiveness of Biodiversity Surrogates for Conservation Planning: Different Measures of Effectiveness Generate a Kaleidoscope of Variation(PUBLIC LIBRARY SCIENCE, 2010-07-14)Conservation planners represent many aspects of biodiversity by using surrogates with spatial distributions readily observed or quantified, but tests of their effectiveness have produced varied and conflicting results. We identified four factors likely to have a strong influence on the apparent effectiveness of surrogates: (1) the choice of surrogate; (2) differences among study regions, which might be large and unquantified (3) the test method, that is, how effectiveness is quantified, and (4) the test features that the surrogates are intended to represent. Analysis of an unusually rich dataset enabled us, for the first time, to disentangle these factors and to compare their individual and interacting influences. Using two data-rich regions, we estimated effectiveness using five alternative methods: two forms of incidental representation, two forms of species accumulation index and irreplaceability correlation, to assess the performance of 'forest ecosystems' and 'environmental units' as surrogates for six groups of threatened species-the test features-mammals, birds, reptiles, frogs, plants and all of these combined. Four methods tested the effectiveness of the surrogates by selecting areas for conservation of the surrogates then estimating how effective those areas were at representing test features. One method measured the spatial match between conservation priorities for surrogates and test features. For methods that selected conservation areas, we measured effectiveness using two analytical approaches: (1) when representation targets for the surrogates were achieved (incidental representation), or (2) progressively as areas were selected (species accumulation index). We estimated the spatial correlation of conservation priorities using an index known as summed irreplaceability. In general, the effectiveness of surrogates for our taxa (mostly threatened species) was low, although environmental units tended to be more effective than forest ecosystems. The surrogates were most effective for plants and mammals and least effective for frogs and reptiles. The five testing methods differed in their rankings of effectiveness of the two surrogates in relation to different groups of test features. There were differences between study areas in terms of the effectiveness of surrogates for different test feature groups. Overall, the effectiveness of the surrogates was sensitive to all four factors. This indicates the need for caution in generalizing surrogacy tests.