Effective Solutions For Controlling Soil Salinity In Canadian Agricultural Sectors

1.Present an agricultural or food science-related issue or problem that needs solving

2.Offer analysis of at least three plausible solutions to the problem by researching pros and cons for each (Doing nothing is not an option to be explored), and:

3.Lead the reader to a proposed solution (your Recommendation), which is based on the facts in the report.

Introduces the subject matter of the report, and that introduces your reader to the ideas you will be discussing. You should address the scope and focus of the report (did you put parameters on your problem, or narrow your focus in a specific way?).

Agricultural Salinity and its Impact

Canada has been facing soil degradation in agricultural sectors since the beginning of this century due to salinity, acidity, wind and other natural or artificial factors. However, the farmers of this country have faced this problem recently and for this, those farmers along with official agencies are trying to control soil quality. Agricultural lands of this country have suffered by waterlogged and flooded farmland that further increase the amount of saturated salts in soils (Kerr 2017). This soil salinity becomes inaccessible for farmers to produce more agricultural foods as dissolved components in soil-water concentration exceed the level of salt requirement of a crop. All kinds of natural waters restrain dissolved gases and solids that further include some amount of salinity. Development of field crops generally depends upon dissolved nutrients that soil solutions contain (Ramírez et al. 2017). However, the chief problem arises when the amount of dissolved salts increases by some amount beyond the requirement level of plants. Thus, excessive salinity prevents crop production and establishment and increase slow growth. Hence, this report will discuss about the problems related to agriculture or food science that the country is facing. Moreover, this report will focus on pros positive and negative sides of three-solution relating to this issue and finally will recommend a suitable solution.

Agricultural salinity implies the impact of salinity on root-zones of crop plants. Hence, salinity problems lead damage of plants and crops to a great extend. On the other side, the salinity tolerance at the root zone of a plant indicates the degree of tolerance up to which crop yield and plant productions remain unaffected. In Canada, many crops like peas, beans, wheat and flax decrease their productivity levels when the amount of salt increases by a small amount. This agricultural productivity problem has led researchers of Agriculture and Agri-Food Canada to fabricate access and design tolerance-testing facility at a high level that can generally determine salinity tolerance of Canadian agricultural sector. Soil degradation generally has seen in the Prairies, where large portions of natural grassland were ploughed previously without considering soil stability or crop capacity (Awada, Lindwall and Sonntag 2014). Soils of prairies generally contain water-soluble salts at a high level that include sodium sulphates, magnesium and calcium. According to the Water Conservation Branch of Prairie Farm Rehabilitation Administration (PFRA), Canada faced huge loss in their national income due to soil salinity in 1983.

Methods for Controlling Soil Salinity

In the Prairie region, almost 12% land of agricultural region was marked as risky due to salinization, at a moderate, high or very high level. However, those regions have improved their soil condition over time and in 2011, and have showed a very low level of risk because of salinization (Kerr 2017). By using a suitable map, one can easily indicate changes in salinization in different regions of Canada, since 1981.

Figure 1: Risk on the Prairies in Canada due to Soil Salinization

Source: (Kerr 2017)

The above figure indicates that risk level has reduced all over the Prairies between 1981 and 2011 and has showed affectively in Saskatchewan. This map has explained this variation by using different colours.

Soil salinity control refers the process to prevent degradation of due to salinization and recover salinized land for agricultural purpose (Panagea, Daliakopoulos, Tsanis and Schwilch 2016). Hence, to control the level of salinity, farmers and other agro-based researchers can apply various methods. However, it is important to mention that there are various natural and man-made assets, which have different levels of salinity tolerance. Hence, it is important to give focus o values and risks when someone is dealing with soil salinity.

The amount of total production in agricultural sectors depends upon several factors, for example, climate condition and the amount of salt content in soil. However, excessive amount of soil salinization in the root zone can prevent growth rate of plants. Hence, it is important to remove excess salts from soil to recover it again for further production. To do reclamation, some methods could be applied, which are scraping, flushing and leaching (Libutti and Monteleone 2017). However, scraping and flushing cannot eradicate salts from soil properly. One the other side, leaching is the most effective method to remove salts from soils. Leaching refers the process where fresh water is stored on the surface of soil to infiltrate. Leaching can be effective by discharging salty waters from the subsurface through drainage system. By this method, leaching can reduce salinity levels through natural drainage system without enhancing the water table (Assouline, Russo, Silber and Or 2015). The process is generally applied when the moisture content in soil is low and when the groundwater table is deep. However, during summer, this process becomes less affective due to evaporation. Hence, this process can be said as different type of irrigation with drainage facility.

Salt Tolerant Crops

Leaching does not only control soil salinization, rather it also has some other impacts. In this process, water runs towards down through the surface of soil that further carries away other materials from soil that help plants to grow further. A minor level of leaching generally occurs due to rain fall that helps to enrich soil with minerals (Bortolini, Maucieri and Borin 2018). However, excessive rain falls or irrigation system negatively affects soils. As a result, ph level can be increased in the soil, which further makes it over acidic. Excessive amount of acid or higher level of pH is not good for plants (Zhao et al. 2017). Moreover, leaching takes away excessive nutrients from topsoil and some nutrients remain in the lower level and go towards the groundwater. This further destroys human health due to excessive nitrate content in ground water. This process further causes soil erosion in an indirect way.

Salt tolerant crops mean those plants, which can tolerate salinity with high level and thir production level does not change due to salinization. Hence, salt tolerance can be stated as the relative growth rate o plants when salinity is presence. Hence, this method is important when irrigated lands have salinity problem and high level of salinization occurs. By applying the elective conductivity of the extract (ECe) in deciSiemens per metre (dS/m), soil can be classified (Matthees et al. 2017). Cotton, sugerbeet and barley are some examples of crops that can be grown in a soil with relatively high salinity. On the other side, corns and beans are grown up in soils with very low level of salt. Sometimes, controlling salinity through leaching and drainage and recovering of soil have become very costly for farmers.

Figure 2: Salinity tolerance of different crops

Source: (Prairiesoilsandcrops.ca 2018)

The above figure is representing the salinity tolerance index of different crops. According to the Agriculture and Agri-Food Canada (AAFC) , higher value is indicating that the crop has greater tolerance.

 In this context, it becomes easier for them to cultivate those plants, which have high level of salt tolerance. Moreover, it becomes economically feasible to produce those crops where good quality of water is not available (Arzani and Ashraf 2016). There are varieties of species within some crops that can tolerate high level of salt. Hence, the genetic potential to develop crops can be obtained. However, this process has some negative impacts or disadvantages. Firstly, production under salinization some time negatively affects human beings and animals. For example, fruits with high salt content are not healthy always. Moreover, this also reduces quality of foods by reducing storage life. Furthermore, salt-tolerant crops need some consideration to breed. Those are related to technical aspects, interactions between management of water and soil with salt tolerance and impacts of salt on the quality of food.   

Management of Soil Salinity

As stated before, soil salinity can be occurred due to various natural causes and human activity. Canada is also facing salinization due to those factors. Natural causes include floods and heavy rain and human activity include irrigation (González-Alcaraz, Jiménez-Cárceles, Álvarez and Álvarez-Rogel 2014). To control soil salinity, a country needs to implement good management system to support their framers so that they can produce agricultural products to a large extent. Hence, except leaching and drainage system and production of salt tolerance crops, the farmer and researcher needs to monitor on the salinity level that can be increased due to irrigation system (Deinlein et al. 2014). For this, it is essential to measure the amount of salt content in the irrigated water. Moreover, excess of crops can be used as mulch that makes a layer on the surface of soil and prevent build up of salts by maintaining soil moisture. Farmers can also apply gypsum to reduce the level of sodium in soil.

Management of soil salinity can control salinization by various methods. For small lands, those methods are affective. But in case of large size lands, those methods are not applicable (Morillo et al. 2014). Hence, to control soil salinity in a large scale, farmers and agricultural researchers need to apply other technology with new and innovative methods as those management systems are old.  

After analysing three methods to prevent soil salinity with their respective pros and cons, a recommendation can be drawn. From the above discussion, it can be said that the production of salt tolerant crops are more affective. In Canada, researchers are receiving various successful outcomes in this context. Moreover, it will feasible for farmers to produce more crops without changing the pattern of soil. This can further reduce the production cost of those farmers. However, to produce more slat tolerant foods, the researchers need to research more. In this context, it is valuable to mention that the Agriculture and Agri-Food Canada (AAFC) has been giving various practical outcomes to the Prairie farmers of Canada, since 1988. They have analysed the level of salt tolerance among wide range of agricultural products and this further has helped them to recommend selected salt-tolerant breeding to farmers for better production.

Conclusion:

In conclusion, it can be said that the vast area of agricultural land in Canada has faced decreasing level of production due to soil salinity. However, the country can overcome this situation by adopting suitable technique through research and development. Soil leaching and drainage, production of salt tolerant crops and other managerial activities regarding control of soil salinity can help agricultural lands to produce more outputs by decreasing the amount of salt. Each method has some advantages and disadvantages. After analysing these all, it can be state that the production of salt tolerant crops is more feasible for farmers. This method can further increase the total amount of output without decreasing the amount of salt in soil.

References:

Arzani, A. and Ashraf, M., 2016. Smart engineering of genetic resources for enhanced salinity tolerance in crop plants. Critical Reviews in Plant Sciences, 35(3), pp.146-189.

Assouline, S., Russo, D., Silber, A. and Or, D., 2015. Balancing water scarcity and quality for sustainable irrigated agriculture. Water Resources Research, 51(5), pp.3419-3436.

Awada, L., Lindwall, C.W. and Sonntag, B., 2014. The development and adoption of conservation tillage systems on the Canadian Prairies. International Soil and Water Conservation Research, 2(1), pp.47-65.

Bortolini, L., Maucieri, C. and Borin, M., 2018. A Tool for the Evaluation of Irrigation Water Quality in the Arid and Semi-Arid Regions. Agronomy, 8(2), p.23.

Deinlein, U., Stephan, A.B., Horie, T., Luo, W., Xu, G. and Schroeder, J.I., 2014. Plant salt-tolerance mechanisms. Trends in plant science, 19(6), pp.371-379.

González-Alcaraz, M.N., Jiménez-Cárceles, F.J., Álvarez, Y. and Álvarez-Rogel, J., 2014. Gradients of soil salinity and moisture, and plant distribution, in a Mediterranean semiarid saline watershed: a model of soil–plant relationships for contributing to the management. Catena, 115, pp.150-158.

Kerr, J.G., 2017. Multiple land use activities drive riverine salinization in a large, semi?arid river basin in western Canada. Limnology and Oceanography, 62(4), pp.1331-1345.

Libutti, A. and Monteleone, M., 2017. Soil vs. groundwater: The quality dilemma. Managing nitrogen leaching and salinity control under irrigated agriculture in Mediterranean conditions. Agricultural water management, 186, pp.40-50.

Matthees, H.L., He, Y., Owen, R.K., Hopkins, D., Deutsch, B., Lee, J., Clay, D.E., Reese, C., Malo, D.D. and DeSutter, T.M., 2017. Predicting Soil Electrical Conductivity of the Saturation Extract from a 1: 1 Soil to Water Ratio. Communications in Soil Science and Plant Analysis, 48(18), pp.2148-2154.

Morillo, J., Usero, J., Rosado, D., El Bakouri, H., Riaza, A. and Bernaola, F.J., 2014. Comparative study of brine management technologies for desalination plants. Desalination, 336, pp.32-49.

Panagea, I.S., Daliakopoulos, I.N., Tsanis, I.K. and Schwilch, G., 2016. Evaluation of promising technologies for soil salinity amelioration in Timpaki (Crete): a participatory approach. Solid Earth, 7(1), p.177.

Prairiesoilsandcrops.ca. (2018). Prairie Soils and Crops. [online] Available at: https://www.prairiesoilsandcrops.ca/ [Accessed 4 Mar. 2018].

Ramírez, D.A., Kreuze, J., Amoros, W., Valdivia-Silva, J.E., Ranck, J., Garcia, S., Salas, E. and Yactayo, W., 2017. Extreme salinity as a challenge to grow potatoes under Mars-like soil conditions: targeting promising genotypes. International Journal of Astrobiology, pp.1-7.

Zhao, X., Deng, H., Wang, W., Han, F., Li, C., Zhang, H. and Dai, Z., 2017. Impact of naturally leaking carbon dioxide on soil properties and ecosystems in the Qinghai-Tibet plateau. Scientific Reports, 7(1), p.3001.