Jim Peterson

LiDAR-Derived High Quality Ground Control Information and DEM for Image Orthorectification

Orthophotos (or orthoimages if in digital form) have long been recognised as a supplement or alternative to standard maps. The increasing applications of orthoimages require efforts to ensure the accuracy of produced orthoimages. As digital photogrammetry technology has reached a stage of relative maturity and stability, the availability of high quality ground control points (GCPs) and digital elevation models (DEMs) becomes the central issue for successfully implementing an image orthorectification project. Concerns with the impacts of the quality of GCPs and DEMs on the quality of orthoimages inspire researchers to look for more reliable approaches to acquire high quality GCPs and DEMs for orthorectification. Light Detection and Ranging (LiDAR), an emerging technology, offers capability of capturing high density three dimensional points and generating high accuracy DEMs in a fast and cost-effective way. Nowadays, highly developed computer technologies enable rapid processing of huge volumes of LiDAR data. This leads to a great potential to use LiDAR data to get high quality GCPs and DEMs to improve the accuracy of orthoimages. This paper presents methods for utilizing LiDAR intensity images to collect high accuracy ground coordinates of GCPs and for utilizing LiDAR data to generate a high quality DEM for digital photogrammetry and orthorectification processes. A comparative analysis is also presented to assess the performance of proposed methods. The results demonstrated the feasibility of using LiDAR intensity image-based GCPs and the LiDAR-derived DEM to produce high quality orthoimages.

Assessing regional sustainability: the case of land use and land cover change in the middle Yiluo catchment of the Yellow River basin, China

Abstract Land use in long-settled areas outside zones especially affected by climatic change and not much or long subject to rapid economic development can be shown to reflect sustainable practice. The research reported here used terrain characteristics of such areas (over five land-use types) to establish a benchmark framework for assessing land-use suitability. The paper shows that such a framework can be used to assess the degree of sustainability of land-use changes, the latter being identified by analysis of time-lapse (1996–9) Landsat Thematic Mapper data. The assessment framework comprises a hybrid physically/statistically based model, suitable for deployment in sustainability assessment requiring comparatively fine spatial resolution.

Late Quaternary aeolianites, palaeosols and depositional environments on the Nepean Peninsula, Victoria, Australia

Abstract The Nepean Peninsula is a bay-mouth bar near Melbourne. It is comprised of Late Quaternary aeolianites, palaeosols and calcretes. TL dates show that most of the sands from which the aeolianites developed as mobile sand dunes were deposited during times of low sea-level towards 47 and 23 ka BP, and others during times of relatively high sea-level towards 118 ka BP. Aeolian dust mantles were laid down during brief intervals when aeolianite formation had ceased. Incipient soil formation and minor organic staining of the upper 0.3–0.5 m of the dust mantles points to a lull in dune formation and the temporary development of a widespread plant cover. The dust mantles have TL ages of 118, 57, 54, 51 and 47 ka BP, indicating that apart from the 118 ka mantle, most of the deposition was when sea-level was low and the regional climate was drier, windier, colder and under a more continental climatic regime. During times of glacially lower sea-level, the coastal climate in this region was not invariably cold, dry and windy but was punctuated by brief intervals of milder, moister and less windy conditions during which dunes and dust mantles became vegetated and soils began to form. Rapid climatic fluctuations were coeval with aeolianite deposition during times of very low sea-level.

Drainage network modelling for Water-Sensitive Urban Design.

While drainage network models may be relatively easy to assemble as a prerequisite to site selection for infrastructure supporting suburbanisation with Water-Sensitive Urban Design (WSUD), this is unlikely to be the case if the terrain is very subdued. Both ab initio and retro-fit WSUD implementation for such terrain refers, in the first instance, to a drainage network model that includes information on the scope for optimising residential space while conforming to: (1) statutory planning rules about the provision of public open space; and (2) WSUD drainage network design such that runoff waters are retained long enough to allow at least temporary storage. It is shown in this research that a technique applied to condition a LiDAR DEM can accurately model the drainage network of a basin at the land-parcel scale. The drainage network for ab initio WSUD is best defined using multi-flow modelling, with the relative significance of stream segments indicated by their stream order derived using the Strahler method. In contrast, when applying the retro-fit WSUD, the relative significance of segments given by the Shreve stream order method was found to be more useful. The approaches described in this article are designed to support the initial site planning stage and avoid the need for immediate and expensive detailed field survey. At the same time they can be deployed to show how much scope there is for WSUD retro-fit in established housing areas up-stream of an infill development area. Thus, basin-wide appraisal is facilitated and the need for earthmoving is minimised.

Geographical Information Systems in Victorian Secondary Schools: Current Constraints and Opportunities.

Whilst widespread diffusion and adoption of spatial enabling technology, such as geographic information systems (GIS), is taking place within Australian public and private sectors, the same cannot be said for GIS within Australian secondary schools and state-based geography curricula. In the Australian state of Victoria, information regarding the status of GIS diffusion within secondary-school geography departments is currently limited, and in this setting, its adoption and use is recognised as relying upon the individual drive of committed geography teachers and schools, rather than any policy innovation. This paper reports the findings of a survey regarding the current state of GIS-based geography education in Victorian secondary schools, which was administered to Victorian secondary geography teachers via an anonymous online survey instrument during 2008. Results show that there are many barriers and constraints affecting adoption and use of GIS for geography teaching and learning in Victorian secondary schools. They include “bottom-up” resistance that might be overcome by GIS-based geography teacher training and “top-down” failure to support GIS-based education in secondary geography curriculum. In recognition of policy documents and statements by lead agencies in favour of GIS-based geography curriculum in Australian and Victorian secondary schools (including documentation relating to a proposed National Geography Curriculum), the survey results reported here can be regarded as important baseline information prerequisite to consensus-building regarding the place of GIS-based geography teaching and learning.

Flood-tide Delta Morphological Change at the Gippsland Lakes Artificial Entrance, Australia (1889–2009)

Abstract Analysis of historical survey and navigation charts, aerial imagery, and digital hydro-data (representing a time-series of 1889–2009) allows the morphological evolution of a flood-tide delta at the artificial entrance to the Gippsland Lakes (Victoria, Australia) to be visualised and quantified. Analysis shows that flood-tide delta growth has imposed progressively greater demands upon port managers for publicly funded maintenance dredging. This flood-tide delta growth corresponds with a progressive diminution of Gippsland Lakes catchment river discharge volumes, and dampening of flow variability, due to both regional precipitation pattern changes and changes in catchment water resource allocation. Future climate change predictions for the Gippsland Lakes catchment and coastal area suggest both further decreases in catchment river discharge, and changing sediment flux along this sector of the Ninety Mile Beach. Thus, scope for flood-tide delta nourishment will probably increase, as will the demand for mitigation of the inevitable effects upon entrance channel navigability. Information derived from the analysis of time-series bathymetry used for this study offers baseline information in support of stakeholder consensus building regarding options for maintaining navigability. Analysis points to the merit of considering (and testing via morphological modelling) alternative options for navigation channel maintenance than those in present practice. We argue that the circumstances prevailing at the artificial entrance call for consideration of engineered configuration changes practised elsewhere by entrance managers faced with similar issues.

Sorption and Fractionation of Copper in Soil at a Sewage Irrigation Farm in Australia

Abstract Copper (Cu) is an important heavy metal to be considered in soil contamination, because high concentrations of copper in soil produce toxic effects and may accumulate in plant tissues. In Australias oldest sewage irrigation farm, located in Werribee, Victoria, soil in the land filtration area is contaminated by Cu. However, Cu content in herbage tissues is in the normal range and has been trending downward since 1979. Therefore, studies on the sorption capacity and sequential extraction of Cu in soil at the Werribee Farm is of significance, not only for better understanding the mechanism of transport, chemical processes, and plant uptake of Cu, but also in providing information for the practical management of sewage farm soils. Methods of combining sorption isotherms with sequential extraction procedures were adopted, and the results showed that the soil in the land filtration area at Werribee Farm has a high sorption capacity for Cu, and distribution coefficients, Kf of Cu, were 629 L kg−1 in surface soils (0–20 cm) and 335 L kg−1 in subsurface soils (20–40 cm). The sequential extraction fractions demonstrate that exchangeable and carbonate fractions are very low, only comprising 3.49 to 5.49% of total copper. The other fractions are also discussed. This characteristic of Cu in soil is related to the low concentration of Cu in plant tissues.

Exploring Stakeholder Views Regarding Spatial Information and Enabling Technology Use for ICZM: A Case Study from Victoria, Australia

“Integrated” approaches to coastal management (known as integrated coastal zone management—ICZM) have been adopted widely since the 1992 United Nations Conference on Environment and Development (UNCED). Decision-support for ICZM demands that policy align with practice such that stakeholders can access a range of time-series information across the entire catchment–coastal–marine continuum. Such access, implemented in spatial enabling technology (e.g., Geographic Information Systems—GIS), can enable stakeholders to make assessments of the dynamics of changing environmental, social, demographic, and economic circumstances with more detail than otherwise possible. However, the level of government at which there is failure to recognize the potential for up-grading decision-support in these terms dictates the extent to which innovation is adopted. In Victoria, Australia, ICZM stakeholders are not yet served by any form of dedicated spatial information–sharing framework, despite ICZM policy having been implemented in 1995, and since refined on a regular basis. In this article, we use semi-structured interviews to explore the outlook of Victorian coastal managers regarding the adoption of spatial information and enabling technology use in support of ICZM initiatives. Results indicate that the optimal integrated use of the technology among Victorian ICZM stakeholders is constrained by a lack of relevant policy implementation, and a lack of supporting stakeholder capacity-building programs. Illumination of these issues provides information that can be used to guide future research, policy development, and capacity-building regarding development of an effective spatial information–sharing and use framework for Victorian ICZM.

GA-SVM Based Framework for Time Series Forecasting

A framework (hereby named GA-SVM) for time series forecasting was formed by integration of the particular power of Genetic Algorithms (GAs) with the modeling power of the Support Vector Machine (SVM). The proposed system has potential to capture the benefits of both fascinating fields into a single framework. GAs offer high capability in choosing inputs that are relevant and necessary in predicting dependent variables. With these selected inputs, SVM becomes more accurate in modeling the estimation problems. Experiments demonstrated that the integrated GA-SVM approach is superior compared to conventional SVM applications.

Morphological Change at the Snowy River Ocean Entrance, Victoria, Australia (1851–2008)

Abstract Analysis of data, including historical documentation, survey and navigation charts, and aerial imagery, representing a time series of 1851–2008 for the Snowy River ocean entrance area (located in East Gippsland, Victoria, Australia) shows that much morphological change has occurred, including entrance channel migration along 8000 m of Holocene sandy barrier formation. Increasingly frequent episodes of Snowy River entrance channel closure to Bass Strait is apparent from reference to the 1981–2008 record. The deployment of GIS technology allows such long-term coastal zone change to be visualised and documented, and, to some extent, quantified. Explanations for this change relate primarily to altered stream flow regimes. Within the Snowy River catchment, hydrological processes have been irretrievably altered after the development of the Snowy Mountains Hydro-electricity Scheme (SMHS) from 1951, which currently appropriates the vast majority of annual discharge from the high rainfall and snowfall areas of the upper Snowy River catchment. Loss of Snowy River discharge volume in the post-SMHS period also refers to a steady diminution of stream flow yield from the unregulated sub-catchments, due to a reduction in catchment rainfall. Whilst ebb-flow augmentation via stream flow discharge is essential to the maintenance of the Snowy River entrance, both long-term below-average catchment rainfall and snow coverage, together with future climate change predictions, leave provision of legislated flow targets for the lower Snowy River in question. Thus, the Snowy River entrance is likely to remain ephemeral in the future as a direct consequence of inter-regional water transfer and climate change.