Almost half of India’s soil cover prone to floods, a third to droughts: Study

The double whammy of droughts and floods are hampering prospects for India’s agricultural productivity
The findings underscore the need for tailored water management policies to optimise agriculture productivity and improve climate resilience across different regions of India.
The findings underscore the need for tailored water management policies to optimise agriculture productivity and improve climate resilience across different regions of India. Photo: iStock/Bartosz Hadyniak

With the severity of heatwaves intensifying and the rainfall pattern getting more erratic with every passing year, a new study has found that about 32.8 per cent of the total land area in India experienced a negative Soil Moisture Anomaly (SMA) in 2023. This means that about 1.08 million square kilometres (sq. km) is vulnerable to drought stress. 

The study revealed that such conditions are possibly affecting agricultural productivity and the management of water resources. 

On the contrary, about 47.7 per cent of India’s geographical area saw soil moisture levels exceeding historical average indicating wetter soil conditions than usual. The positive anomaly on about 1.57 million sq km  increased the risks of flooding and water logging in rural and urban parts of the country. 

The findings have been noted in a study published in the Springer journal that underlines the significance of understanding soil moisture content for predicting droughts in agriculture and how climates impact each other.

It is for the first time that researchers claim to present detailed state-wise assessment of seasonal, pre-monsoon, monsoon and post-monsoon SMA. The findings underscore the need for tailored water management policies to optimise agriculture productivity and improve climate resilience across different regions of India. 

It also highlighted the disparities between regions across different seasons and suggested mitigation measures that could be adopted from other states and achieve sustainability.

“For example, the rice paddies in West Bengal need a different amount of water than the wheat fields in Punjab. Similarly, management styles that work well on farms that are watered in Gujarat might not work well on fields that get their water from rain in Odisha,” it noted.

The study titled Unearthing India’s soil moisture anomalies: impact on agriculture and water resource strategies analyses the changes that have occurred in the soil moisture levels across India by comparing data from 2023 with historical averages between 2000 and 2005. 

For this study, the scientists used soil moisture at the depth of 0 to 10 cm. 

Asserting that soil moisture is a critical natural factor that immensely influences water management practices and sustainability of cultivation, researchers said fluctuations in soil moisture levels directly impact crop yields, water availability and food security, thereby causing unique challenges across various climatic zones of India. 

The study also noted that between June and September the anomalies in soil moisture was recorded to be in significant deficit at -2.1 mm stretching across 498,677 sq km suffering drier conditions. The conditions warranted water conservation measures. 

Also, a state-wise analysis between December and February revealed that Punjab benefitted from positive soil moisture anomalies ranging from 1.19 mm to a maximum of 8.75 mm, boosting its agriculture productivity during winter months. 

The researchers suggest the positive SMA could be used for winter crops, reducing the need for surplus irrigation.

Conversely, Odisha was found experiencing negative SMA with -0.59 mm displaying dried conditions compared to its historical average. 

“However, aligning Odisha’s water management strategies with practices used in Punjab could help mitigate these deficits. For instance, adopting efficient irrigation techniques and water conservation practices from Punjab could benefit Odisha by optimising water usage during the dry winter months,” the study stated.

State-wise findings

Bihar showed negative SMA indicating less-than-average moisture levels, demanding improved irrigation and water conservation methods. Andhra Pradesh depicted favourable conditions necessitating the need for water management solutions. 

During the monsoon period as defined by India Meteorological Department (IMD) as June to September and crucial for Indian agriculture owing to heavy rainfall, the study showed that Punjab continues to benefit with positive soil moisture anomalies resulting in robust crops which could be used to prevent flooding and water logging. 

Odisha, during the same timeframe, showed positive soil moisture levels exhibiting near average conditions. For the coastal state, the study suggested that by learning techniques from Punjab to manage excess water Odisha can improve its agriculture output during monsoon months. 

Bihar and Jharkhand continued to reel under below average soil moisture levels, highlighting the need for water conservation and efficient irrigation techniques to address the potential drought impacts, it observed.

It noted that states such as Maharashtra and Madhya Pradesh which registered above average soil moisture levels, showed considerable variability, demanding robust water management policies for stable agriculture. 

Soil moisture levels in Andhra Pradesh during the monsoon period demands customised plans to address changing conditions as levels varied between -0.7 mm and 9.98 mm. Favourable conditions in Kerala emphasised sustainable farming practices. 

The pre-monsoon period ranging from March to May, with warmer temperatures and varied rainfall, signalled high soil moisture variability. Punjab continued to maintain above-average levels of soil moisture, with Odisha showing slight deficit. Sharing water management practices could help Odisha mitigate the situation of pre-monsoon water stress, the authors found.

Andhra Pradesh and Kerala showed favourable conditions, while Bihar exhibited below-average soil moisture, underlining the need for water conservation. The Andaman and Nicobar islands witnessed dry conditions, highlighting the need for improved water management practices. 

Assam requires adaptable agricultural practices owing to varied soil moisture levels, while Maharashtra should necessitate effective water management methods. 

The researchers concluded that the analysis can help in the improvement effectiveness of water management and agricultural practices. It also recommended developing policies specifically designed to address distinct soil moisture conditions in each region such as preparing drought management plans in deficit areas and flood management strategy in surplus moisture areas. 

“Investing in advanced soil moisture monitoring systems using remote sensing and ground-based sensors will provide real-time data, enhancing the ability to make informed decisions quickly,” it stated.

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