Friendly Farming and Low-Input Agriculture Cut Greenhouse Gas Emissions by 24% Over a Decade

According to statistics from the Council of Agriculture, greenhouse gas emissions from the agricultural sector have slowed year by year under the influence of policy factors such as joining the WTO, promoting friendly agriculture, rationalizing fertilizer use, and the three-stage treatment of livestock manure. Emissions fell gradually from 7,274 thousand metric tons in 2005 to 5,537 thousand metric tons by 2015, a total reduction of 24%. Although agriculture accounts for only 1.9% of overall carbon emissions, the Council of Agriculture stressed that, while taking basic food production needs into account, it will keep working to reduce greenhouse gas emissions.

Less Farmland and Friendly Cultivation Reduce Greenhouse Gas Emissions

Regarding the reduction of greenhouse gas emissions such as carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O), Huang Chen-te, deputy director of the Council of Agriculture's Planning Department, said the main factor was that after joining the WTO in 2002, agricultural production was hit by trade liberalization, with basic production indicators including cultivated land area, crop output and livestock and poultry numbers all showing negative growth; in addition, policies promoted in recent years, such as friendly cultivation, rationalized fertilizer use, biogas power generation, improved manure treatment methods, and even the buyback of inefficient old fishing vessels, have also contributed considerably to reducing greenhouse gases.

As for how greenhouse gas emissions are calculated? Huang explained that it follows the statistical method in the 2006 IPCC Guidelines for National Greenhouse Gas Inventories (2006 IPCC Guidelines for National Greenhouse Gas Inventories).

Simply put, Huang said the figures are estimated jointly by cross-ministerial bodies and research institutions. For example, for pig farming or rice growing, how much production area is involved? How much output is produced? And how much greenhouse gas is released? Each item must be counted separately, then calculated according to the reference coefficients provided by the IPCC. Once the individual items are worked out, they are added together to arrive at specific emissions.

Scholar: Mixed Crop-Livestock Farming and Less Nitrogen Fertilizer Can Reduce Emissions

On the reduction of greenhouse gases in recent years, Kuo Hua-jen, honorary professor in the Department of Agronomy at National Taiwan University, offered his own observations. He said that in the past, farming used large amounts of chemical fertilizers and pesticides. These are petroleum products, produced through a series of industrial processes and only available after being imported, so they naturally consume large amounts of greenhouse gases.

In addition, excessive application of nitrogen fertilizer also changes the microbial ecology in the soil. Over long-term use, soil organic matter gradually decreases, leading to soil hardening, making it naturally difficult for plant roots to hold firm, so more fertilizer must be applied, creating a vicious cycle. Nitrogen fertilizer also turns into nitrous oxide (N2O) that escapes into the air, and the warming effect it causes is more than 300 times that of carbon dioxide.

Therefore, Kuo emphasized that relying on organic farming methods based on ecological principles can effectively reduce greenhouse gas emissions through natural ecological fertilizers. He also encouraged organic farms on the market to minimize "buying fertilizer" and to make their own instead, which is more solid.

As for the livestock sector, which accounts for a major share of greenhouse gas emissions, Kuo suggested returning to traditional mixed crop-livestock farming, where farmers use their own crops or household waste to raise poultry and livestock, which can reduce the use of feed; moreover, converting crops into meat for sale on the market is also good for farm household finances. Otherwise, large-scale farming using chemical feed will cause animals to emit excessive methane during digestion, and greenhouse gases will keep rising.

In response to the scholar's suggestions, the Council of Agriculture stressed that although agriculture accounts for a low proportion of overall greenhouse gas emissions, under the international trend of balancing environmental ecology with agricultural development, it will continue to work hard after taking basic food production needs into account.