Van Dongen R.,GIS Section |
Huntley B.,GIS Section |
Gibson L.,Keiran mara Conservation Science Center
PLoS ONE | Year: 2014
The Montebello archipelago consists of 218 islands; 80 km from the north-west coast of Western Australia. Before 1912 the islands had a diverse terrestrial fauna. By 1952 several species were locally extinct. Between 1996 and 2011 rodents and cats were eradicated, and 5 mammal and 2 bird species were translocated to the islands. Monitoring of the broader terrestrial ecosystem over time has been limited. We used 20 dry-season Landsat images from 1988 to 2013 and estimation of green fraction cover in nadir photographs taken at 27 sites within the Montebello islands and six sites on Thevenard Island to assess change in vegetation density over time. Analysis of data averaged across the 26-year period suggests that 719 ha out of 2169 ha have increased in vegetation cover by up to 32%, 955 ha have remained stable and 0.6 ha have declined in vegetation cover. Over 492 ha (22%) had no vegetation cover at any time during the period analysed. Chronological clustering analysis identified two breakpoints in the average vegetation cover data occurring in 1997 and 2003, near the beginning and end of the rodent eradication activities. On many islands vegetation cover was declining prior to 1996 but increased after rodents were eradicated from the islands. Data for North West and Trimouille islands were analysed independently because of the potential confounding effect of native fauna being introduced to these islands. Mala (Lagorchestes hirsutus) and Shark Bay mice (Pseudomys fieldi) both appear to suppress native plant recruitment but not to the same degree as introduced rodents. Future research should assess whether the increase in vegetation cover on the Montebello islands is due to an increase in native or introduced plants. © 2014 Lohr et al.
Stanton P.,PO Box 154 |
Parsons M.,Recreation |
Stanton D.,719 Logan Road |
Stott M.,GIS Section
Australian Forestry | Year: 2014
Meeting all four natural criteria for United Nations World Heritage listing, the Wet Tropics World Heritage Area that covers 61% of the remaining vegetation of the bioregion conserves, on a biodiversity basis, habitats containing threatened species of outstanding universal value from the point of view of science or conservation. As discussed in an accompanying paper by the same authors, the Wet Tropics Bioregion faces a level of habitat change unprecedented in threat and scale and manifested in the transition of sclerophyll forests and woodlands to closed forest habitats, a change attributable to the absence of fire or reduction in its frequency.The implications of habitat change for certain threatened species and ecosystems present a challenge to conserving the ark of biodiversity the Wet Tropics represents. Evidence indicates that the dominant reason for these changes in vegetation patterns is the reduction in fire or its exclusion across a bioregion with the highest rainfall of the nation. It is clear that the bioregion is suffering and with present trends, will continue to suffer, a major loss of habitat diversity. © 2014 Institute of Foresters of Australia (IFA).
Stanton P.,PO Box 154 |
Stanton D.,719 Logan Road |
Stott M.,GIS Section |
Australian Forestry | Year: 2014
The vegetation and geology of the Wet Tropics Bioregion of North Queensland, covering 1 998 150 ha, were mapped at a scale of 1:50 000. The resulting geographic information system (GIS) data base provided an unprecedented opportunity to examine vegetation condition across the entire bioregion. Mapping used colour aerial photography at 1:25 000, informed by ground truthing. Vegetation type, nature of the understory and ground cover, degree and type of disturbance, and the presence of secondary vegetation were described by a coding system, with codes marked directly on the aerial photos.Analysis of these data has confirmed a picture, which emerged from ground truthing, of large areas of sclerophyll woodland and forest being invaded by a rainforest understory that prevents regeneration of the sclerophyll canopy. Fifty-three per cent of the native vegetation of the bioregion consists of non-rainforest vegetation types, dominated in both area and number by sclerophyll woodlands and forests. Seventeen per cent of the 735 713 ha of sclerophyll woodland and forest types were assessed as having suffered irreversible change. Between 25% and 79% of individual forest vegetation types were judged to have been affected by irreversible change. No climatic changes, or changes in the environment, apart from those related to changing fire regimes, were identified as causative factors. Changed fire regimes, predominantly fire exclusion, are considered to be the most likely cause. © 2014 Institute of Foresters of Australia (IFA).
Oo K.S.,University of Tokyo |
Van Ngoc A.,University of Tokyo |
Takeuchi W.,University of Tokyo |
Hlaing N.,GIS Section |
Than M.M.,Research and Training
32nd Asian Conference on Remote Sensing 2011, ACRS 2011 | Year: 2011
National land covers for 10 years (2001 - 2010) are generated from MODIS monthly composites (Takeuchi W. and et al. 2010). The auto-generated land covers are needed to validate based on the local knowledge and local legend. On the other hand, SAFE's technical support provided AVNIR2 images for some training sites in Myanmar. The AVNIR2 image has advantage with better spatial resolution than MODIS. This advantage could be applied to validate the MODIS data. Thus, the training forest cover could be generated from the AVNIR2 image. In the satellite remote sensing, vegetation reflectance could be calculated from the multispectral images. While the land cover reflectance indexes are available, the forest types could be detected based on the decision logic classification. The study maps the mangrove forests of Meinmahla Island and Bogalay area in Ayeyarwaddy delta with overall accuracy of 92%.
Nagaraju M.S.S.,National Bureau of S oil Survey and Land Use Planning |
Reddy G.P.O.,GIS Section |
Maji A.K.,National Bureau of S oil Survey and Land Use Planning |
Srivastava R.,National Bureau of S oil Survey and Land Use Planning |
And 2 more authors.
Journal of the Indian Society of Remote Sensing | Year: 2011
The study area is characterized by low and fluctuating rainfall pattern, thin soil cover, predominantly rain-fed farming with low productivity coupled with intensive mining activities, urbanization, deforestation, wastelands and unwise utilization of natural resources causing human induced environmental degradation and ecological imbalances, that warrant sustainable development and optimum management of land resources. Spatial information related to existing geology, land use/land cover, physiography, slope and soils has been derived through remote sensing, collateral data and field survey and used as inputs in a widely used erosion model (Universal Soil Loss Equation) in India to compute soil loss (t/ha/yr) in GIS. The study area has been delineated into very slight (<5 t/ha/yr), slight (5-10 t/ha/yr), moderate (10-15 t/ha/yr), moderately severe (15-20 t/ha/yr), severe (20-40 t/ha/yr) and very severe (>40 t/ha/yr) soil erosion classes. The study indicate that 45.4 thousand ha. (13.7% of TGA) is under moderate, moderately severe, severe and very severe soil erosion categories. The physiographic unit wise analysis of soil loss in different landscapes have indicated the sensitive areas, that has helped to prioritize development and management plans for soil and water conservation measures and suitable interventions like afforestation, agro-forestry, agri-horticulture, silvipasture systems which will result in the improvement of productivity of these lands, protect the environment from further degradation and for the ecological sustenance. © 2011 Indian Society of Remote Sensing.
Sahu A.,Indian Institute of Science |
Singh S.K.,Banaras Hindu University |
Sahu N.,GIS Section |
Manna M.C.,Indian Institute of Science
Ecology, Environment and Conservation | Year: 2016
Heavy metals are potentially toxic to human life and the environment. Various extraction procedures were employed for measuring extractable concentrations of potential toxic elements in soil. In a greenhouse pot experiment, three taxonomically different soil orders viz. Typic Ustochrepts (alluvial soil), Typic Rhodustalfs (red soil) and Entic Chromusterts (karail soil) with pH ranging from 5.7 to 8.2 were used. These soils were artificially spiked with different Cd levels (0,5,10,25,50 and 100 mg Cd kg-1). After one month of incubation, extractability of Cd in soils was compared by six extractants:DTPA, AB-DTPA, Mehlich 1, Mehlich III, 0.1 N HC1 and CH3COOH to predict Cd bioavailability in soils. African Marigold (Tagetes erecta L.) was used as test species. Suitability of these extractants in relation to plant tissue concentration and uptake of Cd were also investigated. Extractability of Cd in soils varied depending on extractants used. It was found that 0.1 N HC1 extracted the largest portion of Cd irrespective of soil types. Correlation study of Cd content in soil extracted by different extractants with plant tissue concentration and uptake revealed that best extractant was AB DTP A in Typic Ustochrepts, Mehlich 1 in Typic Rhodustalfs and CH3COOH in Entic Chromusterts. Copyright © EM International.
Behn G.,GIS Section |
Zdunic K.,GIS Section
34th International Symposium on Remote Sensing of Environment - The GEOSS Era: Towards Operational Environmental Monitoring | Year: 2011
Any form of environmental monitoring requires measurements to be repeatable, consistent and reliable. The spatial, spectral and temporal resolutions of the Landsat series of satellites are at scales particularly relevant, for which on-ground measurements can be accurately made, and as such are well placed to provide necessary and updated information for land managers. This paper looks at examples of this information and the processes of introducing this technology from research into applications within an operational department. Relevant information on the health, condition and changes occurring in the environment are of great interest from a variety of perspectives. Satellite imagery, primarily due to its synoptic views of landscapes and multi-temporal sensing, is suited for monitoring this information. One of the benefits of continued collection of satellite imagery, by programs like Landsat, is the ability to study changes at landscape scale over time, with changes in vegetation cover being among the most common features sort. Skidmore et al (2002) states, the historical archive of satellite imagery for studying landscape change continues to grow and its duration now covers almost a third of a century. It is unmatched in quality, detail, coverage and importance. The dramatic increase in studies using this archive of historical satellite imagery indicates the growing value of imagery and points to a future where remote sensing data will play a key role in our understanding of how environments are changing and how humans are influencing its health and sustainability. The uptake of information derived from remotely sensed systems within operational departments such as DEC is dependent on many issues. Some of these identified here are: (1) data accessibility, continuity, and standards, (2) outcomes and benefits, (3) involvement of users, (4) training and teaching, and (5) sustainability and acceptance.