Why Is Rice Grown In Water? [Explanation]
Cultivated for centuries, rice can be long, medium, or short grain, white rice or brown rice. The more you learn about rice varieties, the more you will come to appreciate this simple food.
Did you know that nearly half of the world’s population gets half of their calories just from rice? To add to that, rice is considered the primary energy source for over half of the population worldwide.
These are only some of the reasons why so many people rice grows. There are so many health benefits from this crop.
Once you learn about them, you will want to add rice to every single meal!
Why Is Rice Grown In Water?
For every kilogram of grain produced, rice requires around 5000 liters of water. This is one of the few crops that can tolerate water submergence. The reason why rice is grown in water is that the water does not allow weeds to grow.
It cuts off sunlight and aeration to the ground, creating unfavorable conditions for all weeds. To keep their rice clean, rice farmers started using water. However, the growing water scarcity makes it hard for rice farmers to grow rice.
The need for a new rice growers technique has never been greater. For years, the rice changed so that it can survive the submerged conditions without any damage.
Now, it can withstand both severe drought periods as well as the rise of the water tables. Distinguished by the water-related categories of the plant itself, rice can be divided into several different types.
There are rainfed lowlands, deep water, tidal wetland, rainfed upland, and irrigated rice.
What Does Rice Need Water For?
Most of the water that rice needs are used for two things – withdrawal and consumptive use.
The first means that the water came from a surface or underground source. The second is defined as the type of water that is permanently removed.
That means that it did not evaporate or translate through the plant; it is not part of the crops either. Aside from these two reasons, there are a few other reasons why rice needs water.
One of those other reason people tend to use a lot of water for rice growth is to keep salts from building in the soil.
Soil salinity affects rice growth in several ways. Here are only some examples:
- Soil salinity can reduce the germination rate.
- Rice stops growing due to soil salinity.
- Soil salinity causes the roots to stop growing and developing.
- It can affect spikelet sterility.
Because the salts affect the rice, rice farmers have to find ways to keep the soil less salty. Thanks to water, they can do that through the processes of draining and reduced evaporation.
How Is Water Used During Rice Growth?
Ponding is a common practice in rice fields to ensure that there is plenty of water for the crop to absorb. Rice needs water for three main reasons: evapotranspiration, seepage and percolation, and specific water management reasons.
According to reports, almost 25% of all rice water consumption goes to evapotranspiration, while 45% goes to perennial vegetation.
Also, around 16% of fresh water is lost during the rice-growing process.
In addition to evapotranspiration, seepage, and percolation are other ways that water leaves a field:
- Water runs through the soil in a sideways and downward motion and bunds out of the field.
With the growing water scarcity that I mentioned previously, such water losses are unacceptable. These are actual losses for the individual farmer, who counts the total sum of her rice field’s water use as evapotranspiration, seepage, and percolation.
In order to match all of these outflows, the farmer must make sure there is enough irrigation (to supplement rainwater if there is not enough rainfall).
Because of this, there have been innovations in practice to achieve water-saving rice farming.
This is a challenging task that calls for location-specific technology and committed extension work to change farmers’ perceptions of integrated nutrient, weed, and pest management techniques.
Why Does Rice Flourish In Flooded Fields?
While some plants do not need that much water, rice uses the water to flourish. The water is primarily for weed control usage, but it is also vital for the rice itself.
Though rice plants are susceptible to yield loss or even death if the water is too deep for an extended period of time. Thus, “aerenchyma” is vital to the survival of rice and other plants when they are submerged in water.
When gas spaces are created in the plant, they transport the oxygen from the leaves to the roots. Through the leaves, the rice plant receives enough oxygen to keep itself alive.
If not for these gas spaces, the rice may die in the deep water. The roots of the rice plant also have the ability to create reactive oxygen species.
What these molecules do, along with the calcium in the plant, is that they help the creation of aerenchyma when the plant is underwater for too long.
The reactive oxygen species and the calcium ions work together to create a better so-called respiratory system for the plant.
Let me explain this more thoroughly.
What these molecules do is that they help the plant thrive while underwater. It is crucial to understand plants and what conditions are best for them. If we do not examine all these things, that might lead to crop loss due to bad management.
As for rice, all the molecules that I mentioned make them the most flood-tolerant crop plant.
What About Standing Water Requirements?
Standing water is any puddle, pond, rainwater, drain water, or water reservoir where the water does not move.
In order words, the stagnant water is standing water.
During the process of rice growing, the crop only needs standing water because of the weeds. The rice itself does not benefit from the water in any way. However, some of the new water-saving practices encourage weed growth.
It is indeed a way to save a lot of water. Not all types of rice require standing water. There are some types, like upland rice, that grow without much water.
These types of rice are suitable for water-deficient conditions.
There are two reasons why farmers grow rice in water. Firstly, it is because of weed control. The water allows the rice to grow without any surrounding weeds. Secondly, it is because of the fact that rice flourishes in water.
This is true for only some rice varieties, while others can grow without any water.
Hopefully, other, more sustainable, and innovative ways of growing rice in the future so that we can have rice without wasting too much water.