Answer:
Animal agriculture has been on the rise and so it has been the largest contributor to the increased flux. Biomass burning contributes more to the methane flux per year than animal agriculture.
Step-by-step explanation:
The above is the reason why there has been a global methane flux increament in the environment. This is because, the escrements from the animals as well as plants decaying materials and biomass are great contributors to those increased methane.