Soil salinization is a problem facing much of modern agriculture. It can decrease crop yields and biodiversity and increase the risk of floods and soil erosion. Salinization is becoming more and more common, and it will have detrimental effects in conjunction with climate change. But what is soil salinization?
Salinization of soil is when there is excess salt in a field. When a field needs more water than the rain can supply, farmers water their fields with groundwater. This groundwater is full of minerals and salts. Since the plants use up the water but filter out the salts in the water, the salts flow back into the groundwater, making it more concentrated with salt. As more and more groundwater is used to water crops, this water becomes saltier and saltier, until a field is too salty to grow anything on (see photo below). Basically, poor irrigation practices concentrate salts in groundwater and make fields too salty to sustain crop life. Soil salinization can also occur when the water in flooded fields evaporates, leaving behind large quantities of salt. Luckily, there are many ways to prevent this.
Since soil salinization usually happens when crops are heavily watered (either flooded or watered with sprinkler systems), using drip irrigation can prevent soil salinization because it doesn’t use any excess water, thus preventing excess salts. Additionally, using drought-tolerant crops can reduce water usage, preventing salinization. There are also salt-tolerant crops that can withstand salinization, but these still need lots of water, which we should be using less of as climate change progresses.
Soil salinization is one of many problems facing modern agriculture, and we must do what we can to prevent it if we want our food systems to adapt to changing climates. I hope this series of blogs on agriculture gave you a better understanding of our agricultural system.