Grains and the Environment - Essay Example

GRNS 402 Grains and the Environment GRNS 402 Grains and the Environment Introduction Ley farming is an agricultural practice that involves rotating crops with legumes to improve the structure of the soil and to enhance its fertility. The process helps in disease control and pest disruption. The principle of ley farming has found use in different parts globally, and the interest in the system is still growing especially in the countries that experience a Mediterranean climate. The practice is usually applicable at the top end because of the N produced by legume pastures. Legumes provide different quantities of nitrogen depending on the available N levels in the soil, seasonal conditions, and effectiveness of nodulation and the growth of the legume.In many cropping systems, the key N inputs are obtainable through symbioticN2 fixation in forage leys, green manure leys, pastures and other leguminous crops. For environmental and economic purposes, it is important to estimate the inflow of N through symbiotic fixation in these systems to make accurate N calculations to find use in budgeting. Nitrogen lost from cropping systems, and animal activities run into waterways, atmosphere and on the groundwater. Climatic changes and variability further affect the ability of the agricultural systems to conserve N. The effect of the N that escapes having a direct impact on the climate since it emits nitrous oxide N2O (Robertson, et.al, 2013). The underlying principle behind ley farming is the fact that farmers’ plant ley vegetation with an aim of providing forage for their livestock and to enhance soil fertility in order to improve the crop production on their farms (Schultze-Kraft, 2015). Key Features of Ley Farming System Cereal zones face two major deficiencies in phosphorus (P) and nitrogen (N) in the soil. In most cases, nitrogen-containing fertilizers are expensive and at times, the fertilizers do not improve the structure of worn out soils and those soils that are over-cropped. On the contrary, legume dominant pastures enhance the structure of the soil making it easier for the soil to absorb water leading fast buildup of nitrogen levels in the soil. This results into crops gaining enough levels of nitrogen whenever there is need (Department of agriculture and fisheries, 2015). Importance of Ley Pastures in Farming Ley pastures in farming offer a number of benefits such as better control of soil erosion especially when contouring technology is applied in areas susceptible to soil erosion decrease in land degradation increased soil fertility and structure Better utilization of natural resources Improved controls in disease, insects and weed in farms especially when ley system is well managed Increased levels of forage production- this results in an increase in livestock produce that is of excellent quality. An increase in the grazing period due to the availability of high-quality dry pasture enough to push through the dry seasons Improved cereal crop production with more protein levels and higher cropping flexibility Disadvantages of a Pasture Phase in a Cropping Rotation. Grain growers are slowly adopting the pasture phase system as an adjustment of the ley pasture system. The pasture phase system, however, has a less focus on livestock production and concentrates more on the cropping business. In this system, short-term pasture phases are used in breaking up long term cropping phases that take 3-8 years. The breaking up method aims at controlling stubborn weeds and helps in increasing the levels of nitrogen and carbon in the soil (Department of Agriculture and food, 2015). Pasture phase in crop rotation has the following disadvantages. Pasture phase is associated with the use of a range of herbicides such as glyphosate that are causing major environmental concerns and it’s causing birth defects in human n livestock (Ho, 2010). It is hard to end the pasture phase especially when it includes the persistent species. Moisture reduction in the soil for the subsequent crops and in particular with Lucerne Disease recurrence that depends on the species and the subsequent crop Suggest Suitable Pasture Species/Varieties Specific to Your Region. The selection of pasture species is fundamental in maximizing the profitability and the productivity of a farm. There exist variety of legumes and grasses that are either fed by rains or those that depend on irrigation. Legume species are highly preferred due to their high-quality value in feeding and their capability of enhancing soil fertility due to nitrogen fixation. The choice of selecting the specific species to grow depends on soil and climate conditions as well as the feed demand that is available and the cropping system that is available In my region, that is in the south west of Australia, annual species specifically the subterranean clover and annual ryegrass dominates. Currently, there is a development of specific niches for alternative leguminous species like the serradela and biserrula. Subterranean clover is pasture legume that regenerates on its own that does well in dry land farming in Mediterranean or temperate climates. (Simpson et al, 2011) Report the parameters that match the subterranean clover species (Trifolium subterraneumL.) for your region South West Australia has biophysical characteristics such as low rainfall of between 350-550mm, highly acidic soils that have poor water holding capacity and has a Mediterranean climate ( Dolling, Lyons, & Latta, 2011).. These characteristics match’ subterranean clover species since it has features that make it adapt well to the environment. In addition, it is one of the best pasture legumes that is grazing tolerant. Other features of subterranean clover include; The species has an annual life cycle and can grow from autumn to spring. This makes it match with the period that the rainfalls in the region occur. The species regenerates naturally from seeds from its previous seasons meaning that the species does not require re-planting for it to grow. The species is tolerant of regular grazing especially the mass sheep grazing because it has the prostrate habit in growth The species can protect its seed from being eaten by stock since it can bury its burrs. The species has the capability of maintaining a seed bank when some seeds stay dormant and germinate in some years later. This enables its regeneration from year to year (Department of agriculture and food, 2014). Key Factors to Consider When Selecting the Appropriate Pasture Cultivar The basic factors to consider during the selection of the right pasture cultivar includes the flowering period, soil pH and the hard seededness and other factors as discussed below Flowering period The flowering period is an important when selecting the right cultivar to plant as it helps in determining whether the cultivar is persistent in a specified environment flowering time assists in determining the quantity of seed to be set. The most suitable flowering time is the balance that exists between the production of large quantities of feed and setting of high quantities of seed. Cultivars that do not flower immediately produce more feed during the spring season whereas those that flower after a short period can help in setting more seed before the occurrence of the summer drought. Hardheadedness of the cultivars Cultivars have different proportion of seeds that remain dormant or hard during the winter season after the seed set. Low rainfall areas require cultivars that are hard seeded for them to regenerate fast after a period of little or no seed set. High rainfall areas, on the contrary, require cultivars that are not hard seeded since their season are more reliable. Resistibility to diseases A number of diseases affect pasture species especially in areas with high rainfall rates. It is, therefore, necessary to screen cultivars that are available in the market to ensure that there are not susceptible to diseases. The subspecies of the cultivar The best-adapted subspecies are the best cultivars for sowing. One may also consider combining different subspecies for enclosures with adaptable drainage. How these factors influence the management of the pasture phase Environments that experience low levels of rainfall and have short growing seasons should be managed in such a way that only those cultivars that flowers early are sown since there are more persistent. Alternatively, environments with high rainfall levels and have long growing seasons require the sowing of cultivars that flowers later. Compare Lucerne, Sulla and annual legumes Lucerne Lucerne is a good choice for short-term pasture phase of between 2 and four years particularly if there is need to clear grassy weeds using herbicides different to those of pulses and cereals. Lucerne is helpful in feeding weaner lambs as it closes the gap between the completion of the growing period and season when stubbles are available Sulla Sulla offer considerable amount of yields once planted and offered key benefits to livestock because it contains large amounts of tannins in addition to its anti-helmintic features. It does well when planted on red browns soils. Annual legumes It is prudent and important to select a cultivar that fits individuals farming system and rotation practices. It is good to avoid those varieties with high rates of maturity to ensure that the pasture remains green for a longer period. It is important to select a range of maturities to ensure seasonal variations. Discuss the best management practices for a pasture phase from establishment through to bringing the paddock back into the cropping phase. Planning is the fast step in pasture establishment that should begin at least 12 to 18 months before the sowing process. Inadequate planning is the major cause of failure in pasture establishment. Other best management practices include; Soil moisture preservation Presence of enough moisture in the soil ensures timely planting, early growth and increases the survival rate of the species. Control of the voluntary plantation is necessary to preserve soil moisture and to minimize the weed competition rate. Use of better sowing methods Since pasture seeds are too tiny and weak, it is important to use a reliable sowing, method such as direct shallow placement and by planting the seed in a seedbed that is weed free. Use of enough seed Using enough seed is necessary, as it will lead to the development of competitive and productive pasture that will reduce the rate of weed growth and maximize the rates of stocking after the establishment. Use of adapted varieties/ species Though the research and practical demonstrations one come, get the right pasture varieties that are productive and are persistent. Use of certified seeds avoids the occurrence of annoying weeds. Improved insects and weed control techniques There are a few herbicides available for weed control in pastures particularly for pastures that have a combination of grasses and legumes. It is advisable to identify the type of weed early enough and to us the right herbicide immediately during the early stages of the weed development. Consider how the pasture phase maybe managed differently if grown for livestock compared to alternative options, e.g., Hay, green manure, brown manure. Different species of pasture plants respond differently because of grazing. Therefore, proper management is critical for enhancing wellbeing of the pasture, benefitting livestock and improving the sustainability. Legumes require right adaption to the environment and besides proper management is necessary to ensure an appropriate balance between grass species that fix enough nitrogen quantities during the pasture phase. Green manure leys, when used in crop alternations help in adding N to the system and in reducing the growth of perennial weeds like thistle botanically known as Cirsium spp. This is possible through regular cutting of the weed while leaving mulch on the ground. Cutting the weed helps in reducing the quantity of seeds that the weed produces and additionally, it is a bit hard to integrate a grown shoot biomass of a ley that is intact into the soil when plowing. (Dahlin & Stenberg, 2010) References Dahlin, A. S., & Stenberg, M. (2010). Cutting regime affects the amount and allocation of symbiotically fixed N in green manure leys. Plant & Soil, 331(1/2), 401-412. Doi: 10.1007/s11104-009-0261-1 Department of agriculture and fisheries, South Australia, (2015). Ley farming in South Australia. Web. March 22, 2015. Retrieved from. http://www.pir.sa.gov.au/__data/assets/pdf_file/0009/185733/LeyFarming.pdf Department of agriculture and food. (2014). Web. March 22, 2015. Retrieved from https://www.agric.wa.gov.au/pasture-species/subterranean-clover?page=0%2C2 Department of agriculture and food. (2015). Web. March 22, 2015. Retrieved from http://archive.agric.wa.gov.au/PC_90812.html?s=0 Dolling, P., Lyons, A., & Latta, R. (2011). Optimal plant densities of lucerne ( Medicago sativa) for pasture production and soil water extraction in mixed pastures in south-western Australia. Plant & Soil, 348(1/2), 315-327. Doi: 10.1007/s11104-011-0795-x Ho, M. (2010).Lab Study Establishes Glyphosate Link to Birth Defects. ISIS, 4 October 2010 Retrieved from http://nfuontario.ca/upload/files/userfiles/12542-lab-study-establishes-glyphosate-link-to-birth-defects.pdf Robertson, G., Bruulsema, T., Gehl, R., Kanter, D., Mauzerall, D., Rotz, C., & Williams, C. (2013). Nitrogen-climate interactions in US agriculture. Biogeochemistry, 114(1-3), 41-70. Doi: 10.1007/s10533-012-9802-4 Schultze-Kraft, R., (2015). Forage legumes for ley-farming in the tropics. Food and Agriculture Organization. Web. March 25, 2015. Retrieved from http://www.fao.org/ag/agp/agpc/doc/publicat/viet95/v95_107.pdf Simpson, R. J., Richardson, A. E., Riley, I. T., McKay, A. C., McKay, S. F., Ballard, R. A., &... Barbetti, M. J. (2011). Damage to roots of Trifolium subterraneum L. (subterranean clover), failure of seedlings to establish and the presence of root pathogens during autumn-winter.Grass & Forage Science, 66(4), 585-605. doi:10.1111/j.1365-2494.2011.00822.x Read More