Dryland Soil Salinization in New South Wales - Term Paper Example

Dryland Soil Salinization in New South Wales Client Inserts His/her Name Client Inserts Grade Course Client Inserts Tutor’s Name 09/09/2012 People have a common and consistent share of needs from the earth’s resources which is not limited to a clean, safe and healthy environment which are our basic requirements. These needs are threatened largely by climate change which by extension is a result of our own day-to-day interaction with the environment through human activities and practices that cause soil degradation and desertification. In essence we depend on our environment for sustenance and not even the simplest life-form can exist in isolation with the environment and these are sentiments that have been reiterated in some global conventions like The convention on climate change-Rio de Janeiro 1992 and the Declaration on Social Development-Copenhagen, 1995 and Geneva 2000 (World Commission on the Social Dimension of Globalization [WCSDG] 2004). There exists a correlation between our social environment and our natural environment. Our social environment can’t exist without a sustainable natural environment. Degradation is a phenomenon that arises out of this interaction and has observable negative effects on all spheres of our lives including the social and economic. One phenomenon of degradation is dry land salinity. Dry land salinity causes serious land and water degradation in New South Wales; naturally the arid conditions predispose these lands to dry land salinity. Salinity is the accumulation of and mobilization of salts on the earth’s soils (Steppuhn 1996). It is both a natural process and human process like urban salinity through pollution by industrial affluent causing acidic rain and clearing of vegetation replacing it with concrete car parks and buildings disrupting natural drainages (Podmore 2009). In New South Wales alone, approximately 180,000 ha of land have shallow water tables making these lands more prone to this phenomenon (Coram et al. 2000). It occurs in catchment area like Murray, Murrumbigdee, Hunter rivers and Lanchlan. Large areas of the Hunter Rivers for example have saline water within 2metres of the surface. Dry-land salinity is mostly considered a ground water problem since ground water is the main agent causing the problem due to rise in water tables as a result of much seepage of water to deeply seated water tables raising them. Sodium chloride is the commonest salt and occurs naturally on most sub-soils in New South Wales and some from weathering rocks (Steppuhn 1996). Humans have cleared natural vegetation and replaced it with seasonal crops and some pasture that are shallow rooted and which allows a great proportion of rainwater to remain unused by plants and to enter the ground through seeping (George & Rapper 1999). As a result, the shallow rooted vegetation can only absorb ground water on upper surfaces only thus bringing water tables near the soil surface with a lot of dissolved salts. Through absorption and evaporation, these soils are concentrated by salts leading to dry-land salinity (Coram et al. 2000). According to Podmore (2009), the effects of salts near the surface is that it makes hard for plants to take up water from soils making them dehydrated and eventually dry out and die. It is a conventional truth that the earth’s resources including our environment both natural and social are threatened by the very inhabitants and dependents on these resources; humans. Through pollution, and consumption patterns, the world’s resources are put at risk and our existence and survival is challenged (Steppuhn 1996). Take for instance urbanization, a global phenomenon. There is a correlation between urbanization and rise in ground water and this can easily be demonstrated. Urbanization is a social process where cities grow and become urban. Urbanization brings with it construction of roads, buildings and large car parks which are impermeable of water. This interferes with the natural process of evapo-transpiration thus affecting equilibrium and salinity of soils since salts are not inherently bad in soils but in regulated amounts (Csiro 2000). The absence of the natural evaporation process aggregates salinization. If you consider usage and wastage of resources by human, it suggests that man’s own activities produces ingredients for this phenomenon; salinization. Pollution from motor vehicle fumes and industrial fumes has also aggregated this phenomenon (WCSDG 2004). These fumes form clouds and eventually rain through the natural process of transpiration but the rain is acidic thus making soils more saline and unsuitable for plant life thus elevating once productive land to dry lands (Coram et al. 2000). Another human activity is logging. The need for an economic environment supersedes that of the natural. The demands of the present economic realities makes man live unsustainably with their natural environment. Nature in return judges human beings harshly for their mistakes through global phenomenon like desertification and droughts (Steppuhn 1996). Clearance of vegetation cover especially trees is one global problem especially in developing countries due to high demands for energy and the lack of an effective clean energy infrastructure. Clearance of vegetation causes water to seep to deep-water tables thus raising them permanently. When people clear vegetation and trees, this leaves a large proportion of rain water not being used and thus enters the ground through seeping to ground water (George & Rapper 1999). This brings dissolved and accumulated salts to the surface. This is even worse in low lying areas like the wheat belt area of Australia. The process can be reversed by afforestation though since trees are deep rooted and can absorb water from deep lying water tables and also are good regulators of salinity through evapo-transpiration (Csiro 2000). The area affected by dry land salinity in New South Wales is currently reported to be about 140,000 hectares but the phenomenon is likely to increase with the current land use practices (Coram et al. 2000). Where does the solution lie? Since it is our own activities in our social environment that work together to provide necessary and sufficient conditions for salinization and degradation, it is our own conscious efforts and activities that can redress these problems. Most strategies should be aimed at reducing ground water recharge, strategies aimed at changing poor land use practices and good land management practices. One of the best ways is to increase vegetation cover particularly in high recharge areas (George & Rapper 1999). Vegetation either intercepts or uses this running water reducing the amount of water recharge into the ground. Reafforestation also maintains healthy soils that can reduce the prevalence of saline soils by preventing erosion for instance (Csiro 2000). Land reclamation is also very important. It not only reduces salinity but restores full productivity of land. Revegetation with salt tolerant grass for pasture can be helpful, using mulch not only reduces evaporation from soils but also aid in plant growth and reduces erosion, drainage controls through water banks can also help reduce erosion and in turn preventing water logging (Robins 2004). Another aspect of fixing this phenomenon is that of policy. The aim of policy is to avert this scenario through implementation of salinity management methods through preventive strategies and reclamative strategies (George & Rapper 1999). But even in massive intervention, continuing salinization of resources is inevitable and unpreventable. Engineering methods can also supplement these efforts like shallow surface drainage, pumping out saline water may also be a viable solution to salinity (Robins 2004). With all these strategies, one of the fundamental is attitude change among people. They need to be educated and to understand that salinity affects their farm incomes and thus impacting on their well-being (Csiro 2000). Farmers must make personal sacrifices and commitments to salinity prevention through conscious and deliberate tree planting that reduces soil erosion, reduces water logging and provides a natural habitat for flora and fauna. People have it within their own power and will to reduce, respond to and manage soil salinity (Podmore 2009). In conclusion, people need to understand that dry land salinity is not only an agricultural problem with an agricultural cost but also no-agricultural costs as well e.g. loss of bio-diversity, loss of developmental opportunities on flood plains and extinction of plants and animals. List of References Coram, J. E, Dyson P.R, Houlder P. A, and Evans W. R (2000) Australian Groundwater Flow Systems contributing to salinity, Bureau of Rural Sciences, Report for the National Land and Water Resources Audit Csiro, 2000. Management of Dryland Salinity: Future Strategic Direction. Melbourne: Csiro Publishing. George, R. J, and Rapper G. P., 1999. Interactions between trees and groundwaters in recharge and discharge areas, Agricultural Water Management, Vol. 39. Podmore, C., 2009. Dryland Salinity-Causes and Impacts. Primefacts, 936. Pp. 1-6. Available at Accessed 6/09/2012. Robins L., 2004, Dryland Salinity and Catchment Management-A Resource Directory and Action Manual for Catchment Managers, National Dryland Salinity Program, Land & Water Australia, Canberra ACT. Available at Accessed on 07/09/2012. Steppuhn, H. (1996) what is soil salinity Paper presented at the Soil Salinity Assessment workshop,Lethbridge, Canada. World Commission on the Social Dimension of Globalization 2004, a fair globalization: creating opportunities for all, International Labour Organisation, Geneva. Read More