maize and some other shade-loving vegetables. President Erdoğan has called for more marine protected areas in international waters. There are no international waters adjacent to Turkey's territorial waters, of which about 4% is marine protected area. Carbon sinks Turkey has 23 million hectares of forest covering quarter of the country, though over 40% is degraded woodland. Turkey's forests are its main carbon sink and offset about 10% of the country's emissions in 2020. The government said in 2015 that by 2050 "forests are envisioned to stretch across over four-fifths of the country's territory". However warmer and drier air in the south and west may make it difficult to sustain the present forest cover. But, despite regional variations, forests are expected to remain an overall carbon sink. Almost all Turkey's forest land belongs to the state and cannot be privatised. Private afforestation permits have been issued however, to encourage tree planting in areas where tree density is low. Civil society organizations, such as the Turkish Foundation for Combating Soil Erosion and the Foresters' Association of Turkey, are also encouraging reforestation. In 2019, an annual "National Forestation Day" every 11 November was established by President Erdoğan. Junipers have been suggested for reforestation because of their hardiness, but are said to need help to regrow quickly. But, according to Ege University associate professor Serdar Gökhan Senol, the Ministry of Agriculture and Forestry sometimes replants when it should wait for regrowth instead. Three-quarters of Turkey's land is deficient in soil organic matter. This contains soil organic carbon, which is estimated to total 3.5 billion tonnes at soil depth, with 36 t/ha in agricultural fields. Soil organic carbon has been mapped: this is important because carbon emissions from soil are directly related to climate change, but vary according to soil interaction with low levels of soil organic carbon increasing the risk of soil erosion. Turkey is a major producer of marble; it has been suggested that waste from the industry could capture carbon by calcium looping. Economics During the late 20th and early 21st centuries, growth of the Turkish economy, and to a lesser extent population, caused increased emissions from electricity generation, industry and construction, as described by the environmental Kuznets curve hypothesis. And from the 1990s to the 2010s they were correlated with electricity generation. But during the 2010s economic growth and the increase in emissions decoupled somewhat. Since the 1970s the energy intensity