Agriculture in the industrial world has gone A common interest of the contributors is increas through dramatic changes over the past decades. ing the understanding of the turnover of carbon Mechanization in combination with high inputs of and inorganic nutrients in terestrial ecosystems. fertilizers and pesticides has turned deficits of agri The authors approach this topic from different cultural products into surplus. Over the same directions depending on their interests and ex period we have experienced increased environment pertise. Difficulties are identified in the quantifica al problems...