by Jovita Turan, August 3, 2020
In the recent years, the significant increase of human population is causing the increased demand for production which results in the wide spread of conventional farming. The main problems that occur by conventional farming practices are the remarkable changes in the environment and misuse of the natural balance of the ecosystem. As a result, we can see it as the destruction of the ecosystem and the harm to the food chain.
To avoid such damage to nature, there is an alternative practice to conventional farming that is called sustainable agriculture. Sustainable agriculture is the production of food, fiber, other plants, or animal products while using techniques that would protect the environment, public health, human communities, and animal welfare.
In sustainable farming, crops are being produced without toxic chemical pesticides, genetically modified seeds, synthetic fertilizers. Practices that degrade soil, water, or other natural resources are being avoided as well.
POSSIBLE SUSTAINABLE FARMING TECHNIQUES
Soil Enrichment - a central component of agricultural ecosystems
Soils can be enriched naturally by adding composts such as animal manure, plant residues (e.g. roots), or regularly applying organic mulches on the surface of the soil.
Another way to enrich the soil is by crop rotation as it helps in Nitrogen fixation, Phosphorus, and Potassium mobilization from the soil and buildup of the humus levels.
Cover crops are crops to provide ground cover, they can be plowed in or can be cut and left to lie on the soil. The main purposes of this technique are to improve soil fertility, structure, nutrient availability by increasing Nitrogen levels (e.g. legumes as green manure), controlling the erosions, minimizing leaching, controlling weeds, pests and diseases as well as preparing the land for production of other crops (e.g. vegetables or grains).
Agroforestry Practices; Leguminous Trees
Another important sustainable agriculture practice is agroforestry which is the integration of trees into farming systems. The purposes and benefits of trees on farms are to stabilize the soil, to control salinity, to provide windbreaks, to control shade and erosion, to conserve biodiversity. Agroforestry is a source of the production of timber, fodder, and other products such as oils, nuts, and wildflowers. It moderates air and soil temperatures and enhances the land's capacity to store water.
Leguminous trees such as Acacias, Casuarinas, Robinia, Honey locust, and Cassia increase the levels of nitrogen in soils by nitrogen-fixing bacteria on their roots. Most trees take nutrients from deep in the soil profile then lift them into the leaves that fall to the ground and return on the surface of the soil.
Cultural/Physical/Biological pest and disease control
Cultural pest and disease controls can be called when the plant is grown in optimal conditions: the correct time and position. In this case, the grower should select resistant plant varieties, healthy plants or seeds, use crop rotation, precise irrigation systems and mulching, increase plant diversity, and where possible apply modifications of climate (e.g. proper ventilation).
Physical pests and disease control include hand removal of pests, pruning – removal of modified or infected plant parts, the building of physical barriers such as netting, greenhouses, or insect screens, using traps (e.g. yellow for aphids; white for thrips) and repellent devices.
Biological controls are the use of biologically derived agents such as plants, insects, or animals. Biological control includes:
predators - lizards, frogs, dragonflies, spiders, and birds;
beneficial insects – the release of predators or parasitoids;
attractant plants such as chamomile, celery, hyssop, dill that attracts wasps that reduces populations of caterpillars;
repellent plants or neighboring plants such as garlic that is a general insect repellent;
pheromone traps that have attractant scent from female insects.
Chemical-free weed control practices
Weeds can be controlled by row crop planting for easier cultivation by agricultural machinery, by using woven plastics that allow water and air to pass through them or using organic mulching. The techniques of false/stale seedbed, crop rotations, and flaming are being used widely as well.
While managing soil fertility and reducing land degradation the water efficiency is being increased. To minimize the water loss can be reached by reusing, recycling, conserving, and collecting water as well as using low demand watering systems.
The main techniques to induce water efficiency includes the reduction of evaporation which means the avoidance of midday irrigation and usage of trickle or drip irrigation systems. Another alternative would be rainwater harvesting that cuts down on freshwater use, environmental impact, and costs.
A few more sources of water include underground water (bores or springs), dams, lakes, creeks, rivers, atmosphere catching, recycled waste water, and/or desalination of seawater.
Hydroponics and Aquaponics
The most common urban agriculture growing techniques of hydroponic and aquaponic systems can be considered as sustainable agriculture practice as well. Here, plants are growing without soil only in water with specialized nutrients (hydroponics) or animal, mainly fish (aquaponics) support.
In hydroponics, plants’ roots are directly grown in a mineral solution or an inert medium such as gravel, perlite, etc.
In aquaponics, the combination of aquatic animals (fish) and growing of hydroponic crops are the main components to create the system. The water with the waste material from the fish goes to hydroponic plants and being recirculated back to be reused by the fish.
There are several techniques and ways that could be used to replace conventional farming and reach the main goal which is to protect and maintain a healthy environment on earth!
Prinsley, R.T., 1992. The role of trees in sustainable agriculture—an overview. Agroforestry Systems, 20(1-2), pp.87-115.
Mason, J., 2003. Sustainable Agriculture: Edition 2. Landlinks Press. 212 p.
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