One pound of durian contains two pounds of "carbon". How do agricultural scientists measure carbon emissions reduction for domestic durian?

Xinhua News Agency Haikou, July 21 (Reporter Chen Kaizi) Many people prefer durian, but don't forget that the carbon emissions during their growth process are not low.

On July 20, at the China-ASEAN Durian Industry Seminar held in Sanya, after strict on-site inspection and carbon footprint accounting, the first batch of durian carbon footprint certification certificates in my country, numbered 001 and 002, were issued to two durian planting companies in Hainan Province. This means that as long as consumers see this label, they will know how much greenhouse gas the durian in front of them has emitted before it is put on the shelf.

Certified companies can put a carbon footprint certification mark on durian after picking it and sell it to let consumers know the carbon emissions. Photo by Xinhua News Agency reporter Chen Kaizi

Carbon footprint has become a "hot word" in the field of environmental protection in recent years. Durian carbon footprint is an indicator used to measure the greenhouse gas emissions of the entire durian growth process, usually expressed in carbon dioxide equivalent, which is the "carbon emissions" we are familiar with. During the durian growth cycle, farming, irrigation, application of fertilizers and pesticides, packaging, transportation and other links will cause carbon emissions. At the same time, the improvement of soil organic matter and the photosynthesis of durian trees will also increase carbon sinks and offset part of the carbon emissions.

So, how much "carbon" does a pound of domestic durian emit?

The College of Resources and Environmental Sciences of Nanjing Agricultural University independently developed an orchard carbon sequestration and greenhouse gas emission model, as well as a "life cycle assessment-fruit carbon footprint" method. By collecting samples from farms in Hainan, the main durian producing area in my country, and investigating farmland management conditions, it ultimately calculated the carbon footprint of domestic durian, and obtained support from relevant domestic professional certification companies.

The results of carbon footprint calculation of domestic durian show that for every kilogram of durian produced, approximately 2 kilograms of greenhouse gases equivalent to carbon dioxide are emitted.

Carbon footprint inspectors are collecting soil samples from a durian planting base. Xinhua News Agency

Cheng Kun, associate professor at the School of Resources and Environmental Sciences of Nanjing Agricultural University, told reporters that compared with other fruits, the carbon footprint of durian is currently relatively high. The large-scale domestic durian cultivation has only started to bear fruit in the past two years, and the fruit trees are in their "youth" stage, with low yields, which further increases the carbon emissions of each fruit.

"While everyone is discussing 'durian freedom', we are more concerned about durian's carbon reduction," said Cheng Kun. "Researchers have found that carbon sinks in soil and durian trees can offset a certain proportion of greenhouse gas emissions. Therefore, adopting green and low-carbon management measures to reduce greenhouse gas emissions and increase carbon sinks is very important for reducing durian's carbon emissions."

Now, durian planting areas such as Sanya, Hainan have begun to adopt the biochar soil improvement technology of Nanjing Agricultural University to establish a green and low-carbon planting demonstration base. Planting companies apply biochar to the soil to increase the organic matter content, improve the structure, and enhance the water and fertilizer retention performance. It can not only improve soil quality and crop yields, but also significantly increase soil carbon sinks. The application of this biochar technology is expected to reduce carbon emissions by more than 30% in the future.

The person in charge of Hainan Hongxiang Agricultural Group Youqi Investment Co., Ltd., which obtained the carbon footprint certification certificate, said that agricultural product carbon footprint certification can not only enable consumers to intuitively understand the actual impact of purchasing choices on climate change and promote the green transformation of consumer behavior, but also encourage more agricultural practitioners to develop and adopt green and low-carbon technologies.

Facing the question of how to reduce the high carbon emissions of durian, Cheng Kun is very confident: "In a few years, Hainan's durian yield per mu is expected to continue to double. Combined with the innovation and promotion of green and low-carbon technologies, the carbon footprint will be significantly reduced. In addition, carbon footprint certification will also encourage companies to continuously try new technologies such as improving arable land quality and recycling waste resources, so that durian carbon emissions can be reduced."