Protesters are threatening to shut down the Nassiriya field, and deadly violence has caused one American company to suspend oil operations in the province.
An expansion of Iraq's largest refinery is re-starting after a two-year delay, but other projects are in limbo because high crude prices are squeezing margins for the state-run company.
Bad weather at southern export terminals disrupted tanker loadings and forced shut-ins at oil fields, but spare capacity is ready to come online as OPEC quotas rise.
After years of financing challenges and delays, the Karbala refinery is almost ready to start producing high-quality fuel to feed rising domestic demand.