Site assessment of a woody crop where a shallow hardpan soil layer constrained plant growth

Abstract

The establishment of a woody crop component within dryland agricultural systems in Australia is gaining momentum. Perennial woody crops are assumed to prevent recharge to groundwater and thus control landscape-scale salinization. To optimize the design of these new farming systems it is important to (1) understand the factors limiting woody crop growth and (2) be able to predict survival and growth. On a hill slope, in a water-limited site in southwestern Australia, tree-height was measured across several established belts of a woody crop (Eucalyptus polybractea). The major factor limiting growth was soil depth, with tree-height limited by depths at < 4 m. The tallest trees were associated with a soil depth of 4-6 m in the mid slope position of the sandplain landform. To model growth across the field site, tree-height was regressed against geophysical (magnetic, radiometric, electromagnetic) and topographic data using a multivariate regression tree method. Radiometric and topographic data distinguished two tree-height units which were associated with different soil depths. Radiometric data identified the sandplain landform which included the best growth evident at the field site. Within the sandplain landform, shorter trees were associated with lower elevations. This paper demonstrates the utility of radiometric and topographic data as tools for identifying suitable sites for the establishment of woody crops.

A decadal multi-site study of the effects of frequency and season of harvest on biomass production from mallee eucalypts

“…These junctions are often the site of discharge from perched sandplain aquifers, that are readily depleted with localised tree planting (George, 1990). Investigations of this site reported in Bennett et al (2005) and Pracilio et al (2006) support the conclusion that the sandplain aquifer had been exhausted by the extensive mallee planting of which Site 16 was part. These sites would be optimally managed by matching plantation area to the discharge volume of the aquifer.…”

GIS-based Landform Classification of Eneolithic Archaeological Sites in the Plateau-plain Transition Zone (NE Romania): Habitation Practices vs. Flood Hazard Perception

“…In recent decades, the development of GIS software and free access to datasets has attracted the interest of researchers in implementing new computer algorithms to approach the morphometric attributes and topography of the Earth's surface [2,4]. Also, there has been an upward trend in the use of GIS-based analysis to classify landforms over various scientific fields such as geo-pedology [5][6][7][8], geomorphology and seafloor mapping [9][10][11][12][13][14][15], hydrology [16][17][18], climatology [19], landscape mapping and ecology [20,21], and archaeology [4,[22][23][24]. The morphological features provide useful information…”

Predicting Soil Infiltration and Horizon Thickness for a Large-Scale Water Balance Model in an Arid Environment

“…It appeared that the main reason for the strong correlation between horizon thickness and vegetation was the restriction of the rooting depth for plants in the vicinity of hardpans [38,56]. Furthermore, vegetation may also affect the horizon thickness as a natural selection process and for its advantage [57][58][59].…”