Since humans started practicing agriculture at the expense of natural forests, 8000 years ago, they have affected atmospheric CO₂concentrations. Their impact on atmospheric CH₄ started about 5000 years ago, as result of the cultivation of paddy rice. A challenge of modern agricultural practices is to reverse the impact cropping has had on greenhouse gas emissions and the global climate. There is an increasing demand for agriculture to provide food security as well as a range of other ecosystem services. Depending on ecosystem management, different practices may involve trade-offs and synergies, and these must be considered to work toward desirable management systems. Solution toward food security should not only focus on agricultural management practices, but also on strategies to reduce food waste, more socially-just distribution of resources, changes in lifestyle including decarbonization of the economy, as well as reducing human population growth.