We all know that the excessive use of everything is bad. But could anyone ever imagine the implication of excessive water availability to the soil? As much as plants need adequate water, sunlight, and fertilizers. The excessive and uncontrolled water supply could result in the logging of water and ultimately hinder the development of plants. In the worst cases, it may lead to the death of those plants.
The meaning of waterlogging in a much simpler term is the process of hardening or clogging of the topsoil due to excessive water availability to the soil. In agricultural terms, it can be defined as the extravagant and uncontrolled flow of water, through rain or irrigation practices to crops. When the water available to the soil is much more than what the plant’s root and soil can absorb, then there will be waterlogging on the soil. The most significant effect of this condition on crops is the drop in the level of oxygen available to plants’ roots. Waterlogging on the soil is a common problem in underdeveloped and developing countries where small-scale and medium-scale agriculture is majorly practiced. Large-scale farming usually has a strategy that controls the flow of water to crops. Properly done Irrigation farming is an example of a modernized method of farming that reduces the stagnancy of water on the soil.
Crops need oxygen for normal activities such as respiration and consistent growth. CO2 absorbed by plants during respiration and photosynthesis is broken down into oxygen and carbohydrates. A greater portion of the oxygen obtained by the plant is released into the surroundings while the remaining portion is stored in the root for other purposes. In severe cases, plants undergo anaerobic respiration to survive. This condition is called “anaerobiosis”, a condition of respiration when oxygen is absent. Plants may stop growing well, undergo denitrification, experience an evident decrease in the secretion of manganese and iron oxides, and eventually die off. Waterlogging is not usually detected until it has led to severe damages to the crops. Prompt detection reduces its effect on soil, plants, and the surrounding environment. Agriculturists need to know the signs of waterlogging on the soil for prompt detection and treatment. Waterlogging at the beginning stage leads to the yellowish coloration of the leaves. It also leads to wilting of leaves, smelly roots, and abnormally colored roots. Later signs are decomposition, stunted growth, and dying off of plants.
Summarily, waterlogging is the situation where there is oversaturation beyond the water holding capacity of the soil. It leads to clogging and obstruction in the flow of oxygen.
Forms of Waterlogging in Agriculture
There are various forms of waterlogging that occur in agriculture. The forms of waterlogging are:
- Periodic waterlogging
- Subsoil waterlogging
- River waterlogging
- Ocean waterlogging
Here, rainwater accumulates on depressed or flatlands and results in waterlogging of soil.
This is when water enters the roots of plants. This usually happens during heavy rainfall or extensive irrigation practices.
Here, there is an inflow from the bigger water sources like rivers into the farmlands. This is caused by extensive rainfall.
This is caused by adverse weather conditions such as earthquakes. Here, water from oceans flows into the farmlands.
Causes of waterlogging
The causes of waterlogging are:
- Badly practiced irrigation
- Poor medium of drainage
- Land Topography
- Heavy rainfall and flood
- Soil permeability
- Seepage inflow of water
Badly practiced irrigation
The intensive method of irrigation exposes soil to waterlogging. This is because water seeps through the soil and there is a rise in the groundwater table.
Poor system of drainage
In the absence of a proper draining system to evacuate water during rainfall, water remains stagnant on the soil. This is a major cause of waterlogging in agriculture. A drainage system helps to evacuate water from the land.
The topography of land includes the sloppiness, shape, and other physical features of particular land or environment. Some lands are accelerated such as hills and valleys, while some lands are depressed such as lowlands. Accelerated lands have high steeps and prevent waterlogging. While depressed lands are flat and encourage stagnant water. This becomes worse in the absence of a proper drainage system.
Heavy rainfall and flood
Excessive rainfall is a natural cause of waterlogging. Water may remain on the land for several days especially if the soil has low porosity or permeability. A flood is a natural disaster that results in the accumulation of water. Flooding is more destructive to plants and usually leads to the dying off of plants.
The different types of soil have different porosity and water permeability. For instance, loamy soil is more permeable and porous than other types of soil. In the advent of excessive rainfall, loamy soil absorbs more water than clayey soil and prevents or reduces the effect of waterlogging on the soil.
Seepage inflow of water
Lands that are closer to large water bodies are more likely to experience water inflows to the land. This effect can be reduced by utilizing water effectively. Water from rivers can be treated and used for industrial purposes.
Effects of waterlogging
Waterlogging has numerous effects on plants. The effects of waterlogging are:
- Poor aeration
- Retarded growth of plants
- Increased salinity
- Growth of unwanted plants
- Lowered soil temperature
- Difficulties in performing farm operations
- Environmental pollution
Poor aeration of the soil
Excessive and indiscriminate supply of water to plants leads to a reduction in the supply of oxygen to plants. Aeration is the process of air circulation in the soil. Plants produce oxygen during the day. A larger portion of the oxygen produced by plants is in the environment. While the remaining portion is stored in plants’ roots. When water-logging occurs, the oxygen stored in the plant root is lost due to excessive moisture.
Anaerobiosis is the condition of anaerobic respiration in plants. In extreme cases of waterlogging, plants lose the oxygen required for their normal respiration. Thus, they resort to anaerobic respiration, a condition of respiration in the absence of oxygen.
Retarded growth of plants
Waterlogging disrupts the normal biological function of plants. Excessive supply of water to plants reduces the supply of oxygen and nitrogen to plants. Since both elements are fundamental to the growth of plants, disruption in their supply will retard the growth of plants.
This is usually more common in intensive methods of irrigation farming. Salts are accumulated in the root of plants due to the accumulation of minerals in the water.
Growth of unwanted plants
Some water-loving and wild plants thrive more during the condition of waterlogging. These unwanted plants compete with the main crops for nutrients and sunlight. They outgrow the main plants and retard their growth. In some cases, it eventually causes the crops to die. The growth of unwanted plants reduces the profit of farmers. A large amount of money is spent to get them destroyed.
Lowered soil temperature
Due to the moist environment created by waterlogging, there is a fall in the temperature of the soil. Low temperature encourages the activities and functions of microorganisms. Some chemical substances that are harmful to plants are also bred.
Difficulties in performing farm operations
Many farm operations such as weeding, plowing, planting, and more are best carried out in dry environments. Waterlogging prevents farmers from carrying out many activities on the farm or makes those activities harder to perform.
Waterlogging leads to water pollution in the environment. The accumulated water serves as a medium for the growth of microorganisms. It may also harbor dirt and unwanted objects. It may pose a great danger to the environment.
How to prevent waterlogging in agriculture
Due to the effect waterlogging has on soil, plants, the ecosystem, and agriculturists, it is necessary to prevent the occurrence of waterlogging on lands. Agricultural industries can prevent waterlogging through the following ways:
- Growing crops in raised beds
- Practice good drainage system
- Minimizing seepage inflow
- Proper irrigation management
- Alternating farming methods
Growing crops in raised beds
This method is more effective when the land or area of farming is small. For example, backyard gardens and small-scale farms. The beds of the crops may be raised to a higher level to avert waterlogging. Although, this method is very stressful and requires a lot of effort by the farmer. But provides reliable prevention to waterlogging and protects crop roots from excessive water.
Practice good drainage system
This is an important precaution against waterlogging in agriculture. Farmers should ensure that their farms have a reliable drainage system. It ensures that water is properly evacuated from the farm. When draining water away from farms, farmers should ensure that the water does not remain stagnant on another person’s land or farm. This is to prevent affecting the environment or someone else with waterlogging. There are natural and man-made systems of draining water in agriculture. The farmer should adopt the method that is the best fit for his crop and type of land.
Mulching provides a better and more practicable solution to the problem of waterlogging in farms. In Agriculture, mulching is the process of treating the soil with organic or inorganic substances. When these substances are added to the soil, it protects the soil surface and help plants grow. It also helps to reduce the rate of evaporation. It is however advisable to use a thicker mulch of organic substances in severe cases of waterlogging. Mulching aids soil aeration and eventually eradicate waterlogging on the soil
Minimizing seepage inflow
Water inflows from rivers, canals, and lakes to the farmland can be minimized or blocked to prevent waterlogging. Paths can be created along the water bodies to prevent the inflow of water to the farms. Drainage systems could also be planted along the water bodies to prevent unsolicited inflow of water to the farm. The water bodies could also be widened to aid water flow to its maximum capacity. Also, water from lakes, canals, and oceans can be used more beneficially and economically. This will also prevent unnecessary inflow of water to the surrounding environment.
Proper irrigation management
Proper irrigation management should be practiced to prevent waterlogging of soil. The intensity or deepness of irrigation practices should be below. Proper soil types with the right level of porosity should be used for irrigation. Furthermore, alkaline water or seawater should not be used for irrigation. This is because the minerals present in alkaline water can harden the soil surface and prevent soil from absorbing them. And this will result in waterlogging of the soil.
Alternating farming methods
Crop rotation should be practiced on lands to prevent waterlogging and improve the well-being of the soil. The farmer should endeavor to practice different crop production methods on his land. Also, extensive methods of irrigation farming should not be practiced on land for a very long time. Crops that require intensive irrigation should be encouraged.
In conclusion, waterlogging of soil is a notable challenge in both modern and traditional farming. It may not be easily detected unless close attention is paid to it. The causes of waterlogging are numerous and they are all highlighted in this article. Some are natural while some are man-made. Waterlogging has enormous consequences on the following: soil effectiveness, plants, agriculturists, and the ecosystem, and numerous methods can be employed to stop the incidence and also reduce its effect. This article gives a detailed analysis of the issues surrounding waterlogging in farming. The underlying causes, and practicable prevention.Whats