Under the forest and Ladyswamp ( a radio play and a sonic poem)

'Under the Forest'  and 'Ladyswamp' are audio recordings created in collaboration with musician/ sound artist Tom Kazas. As the first outputs of the ongoing Lyrebird project (fully documented at writingfix.com.au) both works reinvent history in artistic form. At the same time they consider the aftermath of inappropriate farming techniques, representing the sense of disconnection the settlers immediately have from any historical continuity or indigenous relationship to land. In focussing on a regional area in Victoria and the stories that emerge from here, this practice-led research has implications for all other regional areas in countries throughout a world in a time of climate change. The two pieces, linked by the flow of water from the upper catchment of the Tarwin River, to the river flats near the South Gippsland coast, embody the presence of location via poetic means; the flow is from erosion to silt: of land becoming water, becoming land. In the sound design the locations are also represented poetically without losing the actuality of their haunting geography.
The two audio works were first presented at the Double Dialogues Conference: 'The 21st century - The Event, The Subject, The Artwork', Fiji, 2012, and are published in In/Stead, Issue 4, 2013 alongside a discursive article, ‘Under the forest & Ladyswamp: a radio play & a sonic poem’. Extracts of the audio appear on Youtube. The process of ‘Ladyswamp’ appears on an educational video currently in production by Deakin University.

Urban to forest gradients: suitability for hollow bearing trees and implications for obligate hollow nesters

 Resource availability is a limiting factor influencing the distribution and composition of faunal communities. Globally, hollow bearing trees are a resource required by wildlife at all trophic levels, and are used for a diverse range of ecological functions. In the northern hemisphere avian species act as primary hollow excavators, whereas the southern hemisphere must rely on complex interactions between stochastic events, and eventual decay. Hollow formation is therefore a slow process in the southern hemisphere. In contrast, hollow loss is quite rapid and influenced greatly by anthropogenic impacts.To identify the ecological characteristics driving hollows over an urban to forest gradient as a resource for the powerful owl (Ninox strenua) and its prey we used presence-only modelling. The potential for an area to support tree hollows suitable for powerful owls and their prey was linked to the density of ephemeral rivers, land cover, tree cover and distance from riparian vegetation. The potential for large hollows throughout the landscape, suitable for the powerful owl, was also influenced by density of permanent rivers. Potential habitat for tree hollows, capable of supporting powerful owls and their prey was greatest in forested environments, declining with increased urbanization. However the urban region still supported some smaller tree hollows suitable for arboreal marsupials. Managing for urban dwelling species, is not as simple as retaining old hollow producing trees or providing alternate nesting structures. We also need to mitigate increased mortality associated with built environments (e.g. electrocution, collisions).

Understanding the effects of the invasive plants on rural forest-dependent communities

Most of the studies on invasive species are disproportionately focused on their ecological effects and more investigations are needed to understand the effects of invasive plants on rural livelihoods. This study assesses the effects of the invasion of Mikania micrantha-an invasive vine-on the livelihoods of the buffer zone community forest users of Chitwan National Park, Nepal. In this study, the invasive plants are categorized based on their life-form (woody and non-woody) and mode of introduction (accidental or deliberate). The focus is on accidentally transported non-woody species. A household survey revealed that the invasion disproportionately affects the livelihoods of forest-dependent households. In addition, the livelihood effects of invasive plants are particularly determined by the suitability of the invasive plants to produce locally important forest products. © 2014 Steve Harrison, John Herbohn.

Extinction risk in cloud forest fragments under climate change and habitat loss

Aim: To quantify the consequences of major threats to biodiversity, such as climate and land-use change, it is important to use explicit measures of species persistence, such as extinction risk. The extinction risk of metapopulations can be approximated through simple models, providing a regional snapshot of the extinction probability of a species. We evaluated the extinction risk of three species under different climate change scenarios in three different regions of the Mexican cloud forest, a highly fragmented habitat that is particularly vulnerable to climate change. Location Cloud forests in Mexico.
Methods: Using Maxent, we estimated the potential distribution of cloud forest for three different time horizons (2030, 2050 and 2080) and their overlap with protected areas. Then, we calculated the extinction risk of three contrasting vertebrate species for two scenarios: (1) climate change only (all suitable areas of cloud forest through time) and (2) climate and land-use change (only suitable areas within a currently protected area), using an explicit patch-occupancy approximation model and calculating the joint probability of all populations becoming extinct when the number of remaining patches was less than five.
Results: Our results show that the extent of environmentally suitable areas for cloud forest in Mexico will sharply decline in the next 70 years. We discovered that if all habitat outside protected areas is transformed, then only species with small area requirements are likely to persist. With habitat loss through climate change only, high dispersal rates are sufficient for persistence, but this requires protection of all remaining cloud forest areas.
Main conclusions: Even if high dispersal rates mitigate the extinction risk of species due to climate change, the synergistic impacts of changing climate and land use further threaten the persistence of species with higher area requirements. Our approach for assessing the impacts of threats on biodiversity is particularly useful when there is little time or data for detailed population viability analyses.

Differentially private random forest with high utility

Privacy-preserving data mining has become an active focus of the research community in the domains where data are sensitive and personal in nature. For example, highly sensitive digital repositories of medical or financial records offer enormous values for risk prediction and decision making. However, prediction models derived from such repositories should maintain strict privacy of individuals. We propose a novel random forest algorithm under the framework of differential privacy. Unlike previous works that strictly follow differential privacy and keep the complete data distribution approximately invariant to change in one data instance, we only keep the necessary statistics (e.g. variance of the estimate) invariant. This relaxation results in significantly higher utility. To realize our approach, we propose a novel differentially private decision tree induction algorithm and use them to create an ensemble of decision trees. We also propose feasible adversary models to infer about the attribute and class label of unknown data in presence of the knowledge of all other data. Under these adversary models, we derive bounds on the maximum number of trees that are allowed in the ensemble while maintaining privacy. We focus on binary classification problem and demonstrate our approach on four real-world datasets. Compared to the existing privacy preserving approaches we achieve significantly higher utility.