Natural Resource Management, Land Degradation - Essay Example

Problem-based Learning in Natural Resource Management: Land Degradation Institution Name Table of Contents Table of Contents 2 Introduction 3 Identification of land degradation impacts 3 Justification 9 Solutions 11 Counter soil erosion 11 Increase productivity of area under cultivation 12 Increase aggregate area reserved for cultivation: 12 Conclusion 12 References 13 Introduction Land degradation describes a process in which human activities on land affect the value of the biophysical environment. The process causes undesirable alterations on the land leading to permanent or temporary reduction in the capacity of the land to support intended use. Understanding the soil peculiarities and features on the farm is critical as it facilitates the processes for determining whether poor agricultural productivity is caused by nutrient imbalance or deficiency, or soil related problems (GEF, 2006; Scherr & Yadav, 1997). The likely underlying problems need to be addressed to minimise the soil degradation impacts. This paper presents an analysis of a case scenario where land degradation is seen to have far-reaching impacts on the earth surface and consequently on the farming activity at Liverpool plains in Namoi region. The soil types in the farming area under review include the red dermasols on the slopes and black vertosols along the lower slopes near the creek. Identification of land degradation impacts Water erosion in Liverpool area of Namoi region is in most cases rain splash or non-concentrated flows, which erode the top soil as a result reducing the aquatic and terrestrial ecosystem. The degradation further contributes to the lowering of the water table, which exposes the aquifers to direct sunlight and evaporation. The gentler slopes of the areas where Michelle and John practice farming are relatively vulnerable to such impacts as it has loose red dermasols on the slopes that are vulnerable to water erosion. The black vertosols along the lower slopes may be less affected as they have high water holding capacity. Indeed, the soil condition indicator index of the farming area is 3.2, which implies there is a slight loss of soil function that may be noticeable. Vertosol have difference colour ranges, including red, brown, black and grey. They also vary from stronglyc acidic to highly calcareous. Additionally, their depths vary between 030 and 2.00m (See Figure 1). The extent of soil degradation may also be insignificant. Figure 1: Black vertosol Cases of gully erosion of the subsoil and topsoil are also likely due to the concentrated overland flows, which reduce the alternatives for land management, as well as the aquatic and terrestrial productivity of the ecosystem. The black vertosols along the lower slopes near the creek are likely to be affected. While this is a problem in itself, it also contributes to other adverse environmental issues. In the case, since the area lies along the lower slopes adjacent to the creek, severe sheet wash and ‘gullying’ may result. Occurrence of gullies at the upper part of the Namoi Catchment on a tributary of the Mooki Riverand may depict the intensity and the occurrence of the soil degradation processes at the area (See Table 1 & 2). However, the soil condition indicator index is 4.6, showing very minimal extent of degradation (See Figure 3). Land degradation due to wind erosion is also likely. Wind may erode the sub soil and top soil of the black vertosols along the lower slopes adjacent creek, hence minimising the options of land management and reducing the aquatic and terrestrial ecosystem productivity and functions. The indicator index is 3.8, which shows there may be very slight loss of soil function and degradation (See Figure 1). The soil pH is also likely to decline due to the likely carbon decline caused by the recent drought in Namoi region, the likely soil erosion on the upper part of the tributary of the Mooki River that has red dermasols. Dermasols have good drainage due to their well-developed soil structure. Dermasols have a strongly structured subsoil horizon. They also tend to have finely textured contrast between horizon A and B. They have a tendency to encounter aluminium toxiciy if pH declines to below 5.5 (See Figure 2). Figure 2: Red dermasol Soil degradation may also impact the chemical soil properties still left at the original sources (or in situ). In particular, the black vertosols along the lower slopes near the creek may suffer insignificant depletion of metallic cation, especially calcium and magnesium, nitrogen, phosphorus and the change capacity of cation (Desta et al., 2000). However, the soil indicator index is 4.2, which implies very minimal extent of loss of soil function and occurrence of soil degradation (See Figure 3). Change of the soil structure or the architectural arrangement of the soil voids and particles may also happen. The change may affect the soil's gas and water exchange as well as the overall physical health of the soil. The indicator index is 3.1, showing noticeable loss of soil of soil function or degradation (See Figure 1). Land degradation may change the properties of the soil and terrain along the lower slopes adjacent to the creek due to the loss of the topsoil. At the same time, removal of the 5 centimetre layer topsoil of the black vertosols along the lower slopes near the creek may severely affect the shallow soil with a thin soil, although it may not affect the productivity of the deep fertile soil directly (Adewuyi & Baduky, 2012). The black vertosols have high fertility and are known to supply vast plant nutrients. Soil salinity or occurrence of salt on the ground surface may cause significant aquatic and terrestrial ecosystem damage such as massive erosion. Due to the selective removal of colloids and organic matter as a result of soil degradation, the soil may become lighter in colour as well as experience reduced soil biodiversity and biological life. As a result, the soil degradation may reduce productivity, which is associated with biological processes that depend on the variety of organisms available below and above the ground. Additionally, once the soil becomes degraded, its capacity to sustain vegetation biomass will be reduced substantially (Gisladottir & Stocking, 2005). However, the soil indicator index is 3.5, showing insignificant degree of degradation in soil function in Namoi region. Table 1: Soil condition of red dermasols on the slopes at Michelle and John’s farm [(adapted from NSW Government (2010)]. Table 2: Soil condition of black vertosols along the lower slopes near the creek at Michelle and John’s farm Table 3: Legend of Table 1 and 2 Figure 3: Soil condition indicators in the Namoi region Justification From the case, it is clear that land degradation at Liverpool Plains, near Werris Creek, where John and Michelle practice mixed farm would take many forms. However, the most likely ones include change in soil structure, vegetative degradation or terrestrial ecosystem productivity, and lastly soil loss. Soil loss is likely to happen due to the topography and nature of the soil (Gisladottir & Stocking, 2005). For instance, Michelle and John's farm is located in the upper part of the Namoi Catchment on a tributary of Mooki River along the lower slopes adjacent to the creek. Vegetative degradation and biosphere is likely to be accelerated due to the recent drought. The slopes of the area where the farm is located has black vertosols, which crack open when dry becoming less supportive to plant growth (See table 2). Reduced aquatic and terrestrial ecosystem productivity is likely to occur. While the mixed farming or crop-livestock farming system in the upper areas of the Namoi Catchment demonstrate the interdependence between animal husbandry and crop production, increased human activities and settlement on hillsides limit vegetation from growing thus reducing the biosphere (Oldeman, 2000). The situation may further be aggravated by the down flow of rainwater, which explains why there are small pockets of remnant bushland (See Figure 2) (Ocansey, 2013). Change in soil structure is likely to occur, causing depletion of sol nutrients. In the case, it is clear that Michelle and John depend heavily on black vertosols soil, which has high fertility and is known to supply vast plant nutrients. Additionally, beef cattle and irrigated cropping, and small pockets of remnant bushland depend on the soil. The beef cattle depend on the vegetation (small remnant of bushland) that derives nutrients from the soil. Irrigated cropping also depends on the underlying soil nutrients. Additionally, nutrient depletion is likely to be a significant impact of soil degradation due to the mid-altitude hilly nature of the areas and the tendency of the farmers in the area to constantly extract nutrients from the soil for their agricultural activities (Titilola & Jeje, 2008). Figure 4: land degradation, climate change and biodiversity impacts [Adapted from Gisladottir and Stocking (2005)] Solutions Counter soil erosion Mary and John should respond to land degradation by modifying their farming practices or systems through the use of land-improving investments, such as terracing the steep slopes of the valleys to prevent soil loss, especially at the Namoi Catchment on a tributary of the Mooki River. They should also grow cover crops to protect the land from adverse effects of soil erosion from sever sheet wash and likely effects of drought due to exposure of the aquifers to severe heat and evaporation. Examples of these crops include white French millet (Panicum Milliaceum) and Foxtail millet (Setario Italica). Increase productivity of area under cultivation Since the degree of the soil degradation is likely to be reversible, Michelle and John should be advised to rebuild the topsoil, add nutrients to the nutrient-depleted soil and buffer the soil acidity (Desta et al., 2000). However, they will depend on several factors. For instance, the expediency of rehabilitating the depleted top soil on degraded landscape is dependent on the cost in comparison to the expected value of outputs. Michelle and John should also use more fertiliser to increase the nutrient content of the farming soil. Increase aggregate area reserved for cultivation: Michelle and John should also adopt multiple cropping in order to increase the total area for cultivation. They should be asked to engage in smallholder irrigation to use more land for cultivation, to boost the cropping intensity of their land and to minimise the rate of cropping failure due to the recent drought that is likely to have affected the soil biosphere and loss of critical nutrients. Using pump technology, they can feed large areas of land with water from the river. Disregarding the recent drought, the area is endowed with extensive river basin (Titilola & Jeje, 2008). Conclusion To conclude, understanding the soil peculiarities and features on the farm is critical as it facilitates determining whether poor agricultural productivity is caused by nutrient imbalance or deficiency, or soil related problems. In the case, land degradation at Liverpool Plains, near Werris Creek, where John and Michelle practice mixed farm, is seen to take many forms including salination, depletion of soil nutrients, vegetative degradation, change of the soil structure, occurrence of soil salinity, declined soil pH, reduced aquatic and terrestrial ecosystem productivity, severe sheet wash and ‘gullying’, and lastly soil loss. John and Michelle should respond by counter soil erosion and mitigating its effects, increasing productivity of the area under cultivation and increasing the aggregate area they have reserved for cultivation. References Adewuyi, T. & Baduky, A. (2012). Recent Consequences of Land Degradation On Farmland In The Peri-Urban Area Of Kaduna Metropolis, Nigeria. Journal of Sustainable Development in Africa 14(3), 179-193 Castor, P. & Stuat, T. (2006). Short term cover crops increase wheat yields in southern Queensland. Proceedings of the 13th Australian Agronomy Conference. 10-14 September 2006 Perth, Western Australia. Desta, L., Kassie, M. & Pender, J. (2000). Land degradation and strategies for sustainable development in the Ethiopian highlands: Amhara Region. International Livestock Research Institute Socio-economics and Policy Research Working Paper 32 GEF. (2006). Land Degradation as A Global Environmental Issue. Global Environment Facility. retrieved: Gisladottir, G. & Stocking, M. (2005). Land Degradation Control And Its Global Environmental Benefits. Land Degrad. Develop. 16(1), 99–112 NSW Government (2010). State of the Cathment 2010: Soil Condition Namoi Region. Available at available on the DECCW website: www.environment.nsw.gov.au/publications/reporting.htm Ocansey, I. (2013). Mining Impacts On Agricultural Lands And Food Security: – Case Study Of Towns In And Around Kyebi In The Eastern Region Of Ghana. Turku University Of Applied Sciences Thesis. retrieved: Oldeman, L. (2000). Impact of Soil Degradation: A Global Scenario. International Soil Reference and Information Centre Working Paper Scherr, S. & Yadav, S. (1997). Land Degradation in the Developing World: Issues and Policy. International Food Policy Research Institute 2010 Brief 44 Titilola, T. & Jeje, L. (2008). Environmental Degradation and its Implications For Agricultural And Rural Development: The Issue Of Land Erosion. Journal of Sustainable Development in Africa 10(2), 116-146 Read More

The soil pH is also likely to decline due to the likely carbon decline caused by the recent drought in Namoi region, the likely soil erosion on the upper part of the tributary of the Mooki River that has red dermasols. Dermasols have good drainage due to their well-developed soil structure. Dermasols have a strongly structured subsoil horizon. They also tend to have finely textured contrast between horizon A and B. They have a tendency to encounter aluminium toxiciy if pH declines to below 5.5 (See Figure 2).

Figure 2: Red dermasol Soil degradation may also impact the chemical soil properties still left at the original sources (or in situ). In particular, the black vertosols along the lower slopes near the creek may suffer insignificant depletion of metallic cation, especially calcium and magnesium, nitrogen, phosphorus and the change capacity of cation (Desta et al., 2000). However, the soil indicator index is 4.2, which implies very minimal extent of loss of soil function and occurrence of soil degradation (See Figure 3).

Change of the soil structure or the architectural arrangement of the soil voids and particles may also happen. The change may affect the soil's gas and water exchange as well as the overall physical health of the soil. The indicator index is 3.1, showing noticeable loss of soil of soil function or degradation (See Figure 1). Land degradation may change the properties of the soil and terrain along the lower slopes adjacent to the creek due to the loss of the topsoil. At the same time, removal of the 5 centimetre layer topsoil of the black vertosols along the lower slopes near the creek may severely affect the shallow soil with a thin soil, although it may not affect the productivity of the deep fertile soil directly (Adewuyi & Baduky, 2012).

The black vertosols have high fertility and are known to supply vast plant nutrients. Soil salinity or occurrence of salt on the ground surface may cause significant aquatic and terrestrial ecosystem damage such as massive erosion. Due to the selective removal of colloids and organic matter as a result of soil degradation, the soil may become lighter in colour as well as experience reduced soil biodiversity and biological life. As a result, the soil degradation may reduce productivity, which is associated with biological processes that depend on the variety of organisms available below and above the ground.

Additionally, once the soil becomes degraded, its capacity to sustain vegetation biomass will be reduced substantially (Gisladottir & Stocking, 2005). However, the soil indicator index is 3.5, showing insignificant degree of degradation in soil function in Namoi region. Table 1: Soil condition of red dermasols on the slopes at Michelle and John’s farm [(adapted from NSW Government (2010)]. Table 2: Soil condition of black vertosols along the lower slopes near the creek at Michelle and John’s farm Table 3: Legend of Table 1 and 2 Figure 3: Soil condition indicators in the Namoi region Justification From the case, it is clear that land degradation at Liverpool Plains, near Werris Creek, where John and Michelle practice mixed farm would take many forms.

However, the most likely ones include change in soil structure, vegetative degradation or terrestrial ecosystem productivity, and lastly soil loss. Soil loss is likely to happen due to the topography and nature of the soil (Gisladottir & Stocking, 2005). For instance, Michelle and John's farm is located in the upper part of the Namoi Catchment on a tributary of Mooki River along the lower slopes adjacent to the creek. Vegetative degradation and biosphere is likely to be accelerated due to the recent drought.

The slopes of the area where the farm is located has black vertosols, which crack open when dry becoming less supportive to plant growth (See table 2). Reduced aquatic and terrestrial ecosystem productivity is likely to occur. While the mixed farming or crop-livestock farming system in the upper areas of the Namoi Catchment demonstrate the interdependence between animal husbandry and crop production, increased human activities and settlement on hillsides limit vegetation from growing thus reducing the biosphere (Oldeman, 2000).

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