The last drop is what makes the cup run over
Floods hit Central Viet Nam: what can we learn? Researchers in the climate-smart village program are working with farmers to protect them and their farms from extreme weather.
By Le Thi Tam and Elisabeth Simelton
Between 14–16 October and 30 October to 5 November, two heavy downpours hit Viet Nam’s northcentral region, causing floods, landslides and damage to buildings, roads and farm land.
‘The last drop is what makes the cup run over’, said Pham Van Ky, a farmer in My Loi Village, looking over the beige, silty water covering his maize fields.
Village leader Duong Van Tham said, ‘My farm made it through the first flood with only minor damage, like broken trees and soil loss. But the soil couldn’t take any more water so the second flood caused big losses for my family. Some 2500 m2 with 1000 acacia trees and bamboo were all swept away. Luckily, we’d already harvested the peanuts’.
Tropical rain can be heavy: the automatic weather station in My Loi recorded 474 mm on 14 October and another 207 mm the following day. From 4.35 am on 30 October right through to the end of the next day another 330 mm fell.
‘Two to three metres of water after four to five hours of continuous heavy rain’, said Nguyen Song Hao, secretary of the Youth Union in Ky Son Commune.
The water swept through the village, leaving branches dangling off electricity lines after the first and second floods.
It didn’t leave all bad behind it. After the second flood, the saturated soil was covered with a 5 cm thick, silty layer of soil. Even though this damaged some vegetables and maize, it left fine, nutrient-rich silt in fields, which will be good for the next cropping season.
‘Fortunately, most of the rice was already harvested before the first flood’ said My Loi farmer Pham Thanh Thai. ‘Most of us knew from experience, and also advice provided by the commune and village, to plant summer and autumn rice as early as possible to avoid storms that might come in late September or October’.
The worst damages occurred along the stream, where maize, sweet potato and winter vegetables and bamboo grew. Farmers were prepared: they had been following the weather forecast for the preceding three days and had taken a number of measures. Livestock had been evacuated before the first rain, however, the second rain came during the night and many believed the heavy rain was over.
‘That time, farmers failed to rescue some chickens’, said Le Thi Lien.
Fortunately, she kept her goats in a raised cage on stilts and the water didn’t reach the floor. She learned this from neighbouring farmers who had visited the Philippines as part of a project—Agro-climate Information Systems for Women and Ethnic Minorities—supported by the CGIAR Research Program on Climate Change, Agriculture and Food Security.
The flooding was the most recent in a series of extreme events over the past two years. Last year, a tornado hit the village then a cold spell struck at the beginning of 2016. An extended dry season thanks to El Niño had brought drought and hot spells in both years.
‘This shows that when My Loi was identified as a climate-smart village, we certainly had done well in finding a vulnerable site for the project’, said Nguyen Ba Thinh, deputy director of Ha Tinh Provincial Department of Agriculture and Rural Development.
The Ha Tinh Provincial People’s Committee reported on 18 October that 774 hectares of rice and 2497 hectares of other annual crops had been inundated.
‘Flooded crops died or took a while to recover, either destroying or delaying the harvest’, said Tran Van Thong of the Ha Tinh Forest Protect Department. ‘Which influences the planting date of the next cropping season’.
What can we learn from the damage?
‘We are trying to turn these disasters into opportunities to learn from the damage’, said Elisabeth Simelton, leader of the climate-smart villages project. ‘One way is to document the damage and follow-up on the recovery afterwards. This helps us to improve farm adaptation plans’.
The project has introduced updated weather forecasts that inform planning for different scenarios to try to minimize crop failures. In this case, some rice fields were harvested before the events happened.
Flooded maize lost its pollen under the sediment-loaded water, reducing seed formation and productivity. This maize could have been planted a week earlier or later to avoid exposing the most sensitive productivity stage to heavy rain events. This can be guided by using seasonal forecasts to make an appropriate farming calendar and choosing suitable crop varieties.
Monocrop maize planted in late September was affected heavily while neighbouring fields with maize intercropped with sweet potato was less affected. Sweet potato on the ridges helped stabilize the soil and acted as a frame for the maize to lean on, preventing it from being uprooted.
Monocropped vegetables also experienced heavy losses owing to extreme weather, reinforcing that crop diversification can increase farm resilience. Integrating trees on agricultural land can also improve farmers’ adaptation to changing climatic conditions. Trees provide shade, rainwater interception, shelter, windbreaks, reduce soil erosion and provide long-term sources of food, material and income to farmers.
‘Trees, both fruit and timber trees, were less impacted by heavy rains and floods compared to annual crops’, confirmed youth secretary Nguyen.
He explained that trees can recover even after some damage from strong winds and heavy rain and are able to bear fruit and grow well again.
Duong, head of My Loi, attributed the flooding not only to the rain but also low numbers of trees owing to upstream deforestation and unsustainable forest management. Flood prevention and control needed to be implemented at both plot and watershed or landscape levels by improving farming systems through agroforestry and crop diversification, planting more trees to stabilize stream banks, manage forests better and strengthen forest protection.
In the short term, winter is coming. It is high time for farmers, while recovering from their losses due to heavy rains and floods, to learn from the past and be ready for the winter by frequently checking weather forecasts and adapting their farming plans.
My Loi is one of six climate-smart villages in Southeast Asia supported by the CGIAR Research Program on Climate Change, Agriculture and Food Security which aims to develop climate-smart farming systems that contribute to food security, are better adapted to extreme events that are assumed to become more intense as climate change progresses, and also contribute to climate-change mitigation. The Agro-climate Information Systems for Women and Ethnic Minorities project aims to provide practical agro-climatic information and advice. The project is implemented by ICRAF The World Agroforestry Centre and CARE International in Viet Nam, Lao PDR and Cambodia.
ICRAF The World Agroforestry Centre is one of the 15 members of the CGIAR.
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