Semi-automated assignment of vegetation survey plotswithin anapriori classification of vegetation types

Assignment of large numbers of vegetation plots to a priori vegetation classifications is increasingly being required to support natural resource management, monitoring and conservation at regional scales. Several automated systems have been developed that use quantitative synoptic tables and algorithm-based plot-to-type assignment. However, where synoptic tables do not exist, and qualitative species lists characterise vegetation type classifications, existing systems may not apply. In these situations, vegetation experts may resort to manual assignment processes that can be slow, subjective and fraught with difficulties. This study combines repeatable and objective quantitative analyses, with new software, to deliver a semi-automated plot-to-type assignment process appropriate for a priori classifications based on qualitative species lists. The flexible semi-automated assignment program (SAAP) calculates a quantitative goodness-of-fit score between plots and types, based on the species that characterise each a priori vegetation type, and the species that characterise groups of plots derived from quantitative analyses. We applied the SAAP to a case-study of 630 native vascular plant species from 930 plots, and an a priori classification of 99 vegetation types. We varied vegetation data set transforms [cover per cent (0–100%), cover score (0–6) and presence–absence (1, 0)] and analysis settings and tested the degree to which the SAAP provided plot-to-type assignment concordant with manual expert assignment. Results provided clear evidence supporting the choice of particular data set transformations and analysis settings to maximise concordance. The SAAP allocated up to 50% of plots to the same expert-assigned vegetation type, and more than 70% of plots to an expert-assigned vegetation type ranked in the top five by the SAAP. When coupled with repeatable and objective quantitative analyses, the SAAP provides vegetation experts with a new semi-automated and quantitative decision support tool to assist with the assignment of vegetation plots within a priori vegetation classifications defined by characteristic species lists

Clearing of native woody vegetation in the New South Wales northern wheatbelt : extent, rate of loss and implications for biodiversity conservation

Clearing of native woody vegetation in the New South Wales northern wheatbelt was mapped for the period 1985–2000. The study area comprises the Moree 1:250,000 scale map sheet and portions of adjacent map sheets. Unpublished draft mapping of native woody vegetation types, based on 1985 aerial photography and a large set of floristic data from field surveys, was used as a baseline for this study. Mapping of clearing was carried out by intensive visual interpretation of Landsat TM satellite imagery. Systematic validation, which compared the satellite interpretation to low-level aerial photography at randomly allocated point locations, showed that the method was highly accurate in detecting vegetation clearing including in the open woodlands and shrublands that characterise much of the study area. Comparisons with previously published mapping of statewide clearing patterns, based on an automated classification of Landsat TM imagery, showed that our intensive visual interpretation detected substantially more clearing. Average annual clearing rates were 8 times higher that those derived from the previous mapping. Results of the study show that substantial clearing of native woody vegetation is continuing in the northern wheatbelt. Over 110,000 ha of native woody vegetation were cleared between 1985 and 2000. Clearing rates were highest in the four year monitoring period that preceded the introduction of the Native Vegetation Conservation Act. The subsequent two year monitoring period saw substantially lower clearing rates, though further monitoring is needed to determine if this trend will continue. An analysis of spatial patterns highlighted continued high rates of loss in the most depleted parts of the study area. Results for individual vegetation types indicate that regrowth open shrublands and woodlands and Coolabah (Eucalyptus coolabah) dominated woodlands were the most heavily cleared

Land resouces of the Sturt Plateau, Northern Territory - A reconnaissance land system survey

Includes bibliographical references.Due to strong interest shown in property developnent in the northern part of the Sturt Plateau (between the southern boundary of Mataranka Station and Daly waters) and the scarcity of resource information, a reconnaissance land system survey was conducted in October, 1983 and supplemented with additional field work in August , 1984.Summary -- Introduction -- Physiography and drainage -- Land system descriptions -- Soils -- Vegetation -- Land Use Potential -- References -- AppendicesMade available by the Northern Territory Library via the Publications (Legal Deposit) Act 2004 (NT)

by S.J. Lucas & D.P. Sivertsen.

Made available by the Northern Territory Library via the Publications (Legal Deposit) Act 2004 (NT).Date:1980Cover title: Fenton, preliminary report..

S.J. Lucas & D.P. Sivertsen.

Made available by the Northern Territory Library via the Publications (Legal Deposit) Act 2004 (NT).Date:1983-1

by D.P. Sivertsen, P.J. McLeod and R.L. Henderson.

Made available by the Northern Territory Library via the Publications (Legal Deposit) Act 2004 (NT).Date:1980Bibliography: p. 75-76