[YouPass Collect] - Sea Change for Salinity
[YouPass Collect] - Sea Change for Salinity
One of the most serious problems facing Australian farmers is an increase in the salt content in the soil. However, new weapons are emerging in the fight against salinity.
A. Beneath the flat, impassive surface of Australia lie hidden mountains, valleys, and gorges - ancient traps and channels for the deadly salt that is stealthily killing so
A suite of high technologies used by geologists to see underground and prospect for gold and minerals is now being used to pinpoint the presence of salt beneath the
B. Unless this process is clearly understood, warns Chief of Exploration and Mining Dr. Neil Phillips, the hard work now underway - such as planning and tree-planting on
The use of airborne electromagnetic technology to detect salt hidden beneath the landscape has been around for a decade, but the past two years have seen a major development
C. Angus Howell, who farms near Warrenbayne in Southeast Australia, saw his first outbreak of salt in 1948. Over the ensuing decades, the patches spread and multiplied until
But despite a mounting effort by scientists, farmers, and governments, the 'white death' continued to encroach. Small successes were eclipsed by larger defeats and fresh outbreaks.
D. 'The technical solutions just aren't there yet for dealing with broadacre salinity, nor are the social and economic solutions. How do you introduce the land-use changes that
There is no satisfactory solution yet. Part of the problem lies in salt's ability to mount ambushes, emerging somewhere new, sometimes unexpectedly and inexplicably, beating plans to intercept
E. The need for such knowledge is pressing. Salt has already afflicted six million hectares of once-productive land. At present rates, it is predicted that by 2050,
F. Electromagnetic surveys measure the electrical conductivity of soil to reveal the distribution of salt and the nature and variability of the regolith - the weathered rock and
Magnetic surveys measure small differences in the Earth's magnetic field, enabling scientists to probe the deep past and reconstruct ancient landscapes - rivers, basins, and faults now buried
G. Radiometric analysis is based on the detection of radiation emitted by elements contained in rocks and soils, allowing scientists to delineate landforms. These factors influence the
Using data from the Murray River region, scientists have revealed a network of ancient drainage channels buried meters beneath the current landscape. These buried channels may carry salt
H. One of the biggest advances in detection, says Professor Neil Phillips, has come with the integration of different techniques such as magnetics, electromagnetics, radiomagnetics, and ground mapping.
Advanced airborne electromagnetics, in particular, enables scientists to take 'slices' of the landscape at depths of five meters, ten meters, fifteen meters, and so on, to determine where
From such technologies, it will be possible to locate salt stores, identify how saline they are, look at man-made and natural changes to the landscape that may cause it
