cropping and the use of organic mulch, farmers can improve infiltration, reduce evaporation and soil erosion, and build up organic soil content. Between 2005 and 2011, the number of smallholders practicing conservation agriculture in Zimbabwe increased from 5,000 to more than 150,000. Cereal yields rose between 15 and 100 per cent across different regions. The government declared potato a national strategic food security crop in 2012. Mvurwi, a region in Mashonaland Central Province, once fell in the "breadbasket region" of Zimbabwe, with fertile soils. However, over the past 30 years, this is one of the areas that have been negatively impacted by the land reforms, causing it to be less prosperous than it was in the late 20th century. Tourism Since the land reform programme in 2000, tourism in Zimbabwe has steadily declined. In 2018, tourism peaked with 2.6 million tourists. In 2016, the total contribution of tourism to Zimbabwe was $1.1 billion (USD), or about 8.1% of Zimbabwe's GDP. Employment in travel and tourism, as well as industries travel and tourism indirectly supports, was 5.2% of national employment. Several airlines pulled out of Zimbabwe between 2000 and 2007. Australia's Qantas, Germany's Lufthansa, and Austrian Airlines were among the first to pull out and in 2007 British Airways suspended all direct flights to Harare. The country's flagship airline Air Zimbabwe, which operated flights throughout Africa and a few destinations in Europe and Asia, ceased operations in February 2012. As of 2017, several major commercial airlines had resumed flights to Zimbabwe. Zimbabwe has several major tourist attractions. Victoria Falls on the Zambezi, which are shared with Zambia, are located in the north-west of Zimbabwe. Before the economic changes, much of the tourism for these locations came to the Zimbabwe side, but now Zambia is the main beneficiary. The Victoria Falls National Park is also in this area and is one of the eight main national parks in Zimbabwe, the largest of which is Hwange National Park. The Eastern Highlands are a series of mountainous areas near the border with Mozambique. The highest peak in Zimbabwe, Mount Nyangani at is located there as well as the Bvumba Mountains and the Nyanga National Park. World's View is in these mountains, and it is from here that places as far away as are visible and, on clear days, the town of Rusape can be seen. Zimbabwe is unusual in Africa in that there are