Marginal land is often defined as land that has little value for agricultural production because the difference between the costs of agricultural inputs (e.g. labour, machinery, agrochemicals) and the revenue that can be achieved from yields is small compared to  what can be achieved on other land. Marginal land is sometimes defined in contrast with arable land, where marginal land is understood to be land that is unsuitable for crop production but still could be used for grazing by livestock. While the agricultural value of marginal land can be low, both its existing and potential value for biodiversity conservation can be high.