**3. Status of climate change**

#### **3.1 Crop management**

Various methods to reduce greenhouse gas emissions from rice fields can reduce greenhouse gas emissions from rice fields by changing irrigation methods and farming methods, managing organic additives and fertilizer inputs, and choosing appropriate varieties and planting methods. The following section will discuss all these details with suitable options and possibilities in different agro-conditions.

#### **3.2 Changing irrigation pattern**

Irrigation in rice production process is one of the vital features in regulatory greenhouse gas emissions. According to reports, compared with traditional flooded rice, several water managements schemes (such as different drainage periods in the season, alternating wet and dry soil, recurrent irrigation and controlled irrigation) can minimize GHG emissions, Can be used as an option. Practice under different soil and climate conditions without reducing crop yields. Mid-season drainage Midseason drainage includes a significant period of interruption of irrigation during crop growth. Usually, a short-term drainage (5–20 days) is performed before the maximum sub-till number stage to prevent grade growth and reduce the number of invalid sub-tills, and the duration is adjusted by the conventional method of regional determination. At the beginning of soil aeration, CH4 emissions may increase in a short time due to the release of CH4 entrained in the soil, and its emissions will continue to decrease even when the field is submerged again. Since additional water can be used to displace the paddy soil, there is also a difference in the efficiency of midseason drainage in reducing CH4 (15–59%) [12]. Drainage in the spring increases the oxidative conditions of the soil and the uptake of nitrogen [13].

Therefore, this can be achieved by reducing the amount of water applied, because the net reduction in water will ultimately reduce CH4 emissions. Wassmann et al. [14] reported that the aerobic conditions generated by the flux of oxygen discharged into the soil are not conducive to the activities of methanogenic bacteria, therefore, in the medium term, drainage can reduce CH4 emissions by 43%. Timely mid-season drainage management seems to be an important way to obtain net benefits from greenhouse gas emissions [15]. So far, many studies have confirmed its applicability in rice fields based on overall greenhouse gas emissions. Zou et al. [16] recommended mid-season drainage as the best option to reduce greenhouse gas emissions, because they pointed out that the GWP of mid-season drainage was reduced by 27% compared with traditional CH4 and N2O-based floods [17]. Wassmann et al. [18] also reported that the GWP (CH4 and N2O) of the mid-season drainage was reduced by 42% and 72%, respectively,

compared with the traditional flood. Since greenhouse gas emissions are greatly affected by the length and time of sewage discharge.
