When talking re environment & greenhouse effect, we tend to point our fingers to cars and other industries ... true, but we cannot ignore that agriculture is also harming the environment! Farmers should be encouraged via incentives to switch to organic farming and hence reduce use of pesticides and other chemicals that contaminate soil & water. Also, when possible, farmers should be given the opportunity to invest in aquaponics & vertical systems to grow crops.. these systems can be operated from urban / industrial areas. Aquaponics use 90% less water then traditional farming... no chemicals or pesticides.. land which was previously used for agriculture can be planted with trees such as olives ... hence aid reforestation.