Conservation agriculture
Conservation agriculture can be defined by a statement given by the Food and Agriculture Organization of the United Nations as "Conservation Agriculture is a farming system that can prevent losses of arable land while regenerating degraded lands. It promotes minimum soil disturbance, maintenance of a permanent soil cover, and diversification of plant species. It enhances biodiversity and natural biological processes above and below the ground surface, which contribute to increased water and nutrient use efficiency and to improved and sustained crop production."
Agriculture according to the New Standard Encyclopedia is "one of the most important sectors in the economies of most nations". At the same time conservation is the use of resources in a manner that safely maintains a resource that can be used by humans. Conservation has become critical because the global population has increased over the years and more food needs to be produced every year. Sometimes referred to as "agricultural environmental management", conservation agriculture may be sanctioned and funded through conservation programs promulgated through agricultural legislation, such as the U.S. Farm Bill.
Key principles
The Food and Agriculture Organization of the United Nations has determined that conservation agriculture has three key principles that producers can proceed through in the process of CA. These three principles outline what conservationists and producers believe can be done to conserve what we use for a longer period of time.The first key principle in CA is practicing minimum soil disturbance which is essential to maintaining minerals within the soil, stopping erosion, and preventing water loss from occurring within the soil. In the past agriculture has looked at soil tillage as a main process in the introduction of new crops to an area. It was believed that tilling the soil would increase fertility within the soil through mineralization that takes place in the soil. Today tillage is seen as destroying organic matter that can be found within the soil cover. Tilling of soil can cause severe erosion and crusting which leads to a decrease in soil fertility. No-till farming has caught on as a process that can save soil organic levels for a longer period and still allow the soil to be productive for longer periods. Minimum soil disturbance also conserves soil micro and macro-organism habitats that are commonly destroyed in conventional ploughing practices.
When no-till practices are followed, the producer sees a reduction in production cost for a certain crop. The process of tilling increases time and labor for producing that crop. Tillage of the ground requires more money in order to fuel tractors or to provide feed for the animals pulling the plough. The producer sees a reduction in labor because he or she does not have to be in the fields as long as a conventional farmer.
The second key principle in CA is much like the first in dealing with protecting the soil. The principle of managing the top soil to create a permanent organic soil cover can allow for growth of organisms within the soil structure. This growth will break down the mulch that is left on the soil surface. The breaking down of this mulch will produce a high organic matter level which will act as a fertilizer for the soil surface. If CA practices were used done for many years and enough organic matter was being built up at the surface, then a layer of mulch would start to form. This layer helps prevent soil erosion from taking place and ruining the soil's profile or layout. The presence of mulching also reduce the velocity of runoff and the impact of rain drops thus reducing soil erosion and runoff.
According to the article "The role of conservation agriculture and sustainable agriculture", the layer of mulch that is built up over time will become like a buffer zone between soil and mulch and this will help reduce wind and water erosion. With this comes the protection of the soil's surface when rain falls on the ground. Land that is not protected by a layer of mulch is left open to the elements. This type of ground cover also helps keep the temperature and moisture levels of the soil at a higher level rather than if it was tilled every year.
The third principle is the practicing diverse crop rotations or crop interactions. According to an article published in the Physiological Transactions of the Royal Society called "The role of conservation agriculture and sustainable agriculture", crop rotation can be used best as a disease control against other preferred crops. This process will not allow pests such as insects and weeds to be set into a rotation with specific crops. Rotational crops will act as a natural insecticide and herbicide against specific crops. Not allowing insects or weeds to establish a pattern will help to eliminate problems with yield reduction and infestations within fields. Crop rotation can also help build up soil infrastructure. Establishing crops in a rotation allows for an extensive buildup of rooting zones which will allow for better water infiltration.
Organic molecules in the soil break down into phosphates, nitrates and other beneficial elements which are thus better absorbed by plants. Plowing increases the amount of oxygen in the soil and increases the aerobic processes, hastening the breakdown of organic material. Thus more nutrients are available for the next crop but, at the same time, the soil is depleted more quickly of its nutrient reserves.
Examples
In conservation agriculture there are many examples that can be looked towards as a way of farming and at the same time conserving. These practices are well known by most producers. The process of no-till is one that follows the first principle of CA, causing minimal mechanical soil disturbance. No-till also brings other benefits to the producer. According to the FAO, tillage is one of the most "energy consuming" processes that can be used: It requires a lot of labor, time, and fuel to till. Producers can save 30% to 40% of time and labor by practicing the no-till process.Besides conserving the soil, there are other examples of how CA is used. According to an article in Science called "Farming and the Fate of Wild Nature" there are two more kinds of CA. The practice of wildlife-friendly farming and land sparing are ideas for producers who are looking to practice better conservation towards biodiversity.
Wildlife-friendly farming
Wildlife-friendly farming, also known as land sharing, allows for the conservation of biodiversity while also allowing for production of agricultural products. In this approach, land is set aside to preserve the wildlife while the rest is used to fulfill the farmers need of agricultural commodities. Farmers take this approach by leaving some aspects of the land the same while harvesting a diverse grouping of crops around it. This, in turn, allows for animals such as bees to pollinate, and the natural predation of unwanted pests. By practicing such method the harvester can expect to see much lower yields, but also an increase in biodiversity given time. This decrease of yield then gives rise to the idea of land sparing, the maximization of yield in a homogenous landscape.Land sparing
Land sparing is another way that producer and conservationist can be on the same page. Land sparing advocates for the land that is being used for agricultural purposes to continue to produce crops at increased yield. With an increase in yield on all land that is in use, other land can be set aside for conservation and production for biodiversity. Agricultural land stays in production but would have to increase its yield potential to keep up with demand. Land that is not being put into agriculture would be used for conserving biodiversity. In fact, data from the Food and Agriculture Organization shows that between 1961 and 2012, the amount of arable land needed to produce the same amount of food declined by 68 percent worldwide.Benefits
In the field of CA there are many benefits that both the producer and conservationist can obtain.On the side of the conservationist, CA can be seen as beneficial because there is an effort to conserve what people use every day. Since agriculture is one of the most destructive forces against biodiversity, CA can change the way humans produce food and energy. With conservation come environmental benefits of CA. These benefits include less erosion possibilities, better water conservation, improvement in air quality due to lower emissions being produced, and a chance for larger biodiversity in a given area.
On the side of the producer and/or farmer, CA can eventually do all that is done in conventional agriculture, and it can conserve better than conventional agriculture. CA according to Theodor Friedrich, who is a specialist in CA, believes "Farmers like it because it gives them a means of conserving, improving, and making more efficient use of their natural resources". Producers will find that the benefits of CA will come later rather than sooner. Since CA takes time to build up enough organic matter and have soils become their own fertilizer, the process does not start to work overnight. But if producers make it through the first few years of production, results will start to become more satisfactory.
CA is shown to have even higher yields and higher outputs than conventional agriculture once it has been established over long periods. Also, a producer has the benefit of knowing that the soil in which his crops are grown is a renewable resource. According to New Standard Encyclopedia, soils are a renewable resource, which means that whatever is taken out of the soil can be put back over time. As long as good soil upkeep is maintained, the soil will continue to renew itself. This could be very beneficial to a producer who is practicing CA and is looking to keep soils at a productive level for an extended time.
The farmer and/or producer can use this same land in another way when crops have been harvested. The introduction of grazing livestock to a field that once held crops can be beneficial for the producer and also the field itself. Livestock manure can be used as a natural fertilizer for a producer's field which will then be beneficial for the producer the next year when crops are planted once again. The practice of grazing livestock using CA helps the farmer who raises crops on that field and the farmer who raises the livestock that graze off that field. Livestock produce compost or manure which are a great help in generating soil fertility. The practices of CA and grazing livestock on a field for many years can allow for better yields in the following years as long as these practices continue to be followed.
The FAO believes that there are three major benefits from CA:
- Within fields that are controlled by CA the producer will see an increase in organic matter.
- Increase in water conservation due to the layer of organic matter and ground cover to help eliminate transportation and access runoff.
- Improvement of soil structure and rooting zone.