Rice, integral to Madagascar, may be hastening the decline of its unique biodiversity; here is how

Rice, integral to Madagascar, may be hastening the decline of its unique biodiversity; here is how

Subject :Environment

Context-

• Rice, the main food crop of Madagascar, could be hastening the deforestation and loss of biodiversity in the fourth-largest island of the world due to the practice of shifting agriculture, according to two exhaustive studies published in the Science journal.

More on the news-

• Study named- Madagascar’s extraordinary biodiversity: Evolution, distribution, and use
• Climate change has wrought havoc on the island, with the latest being Tropical Storm Ana earlier this year.

Rice and zebu cattle-

• Rice cultivation was brought a millennium ago to Madagascar by Austronesian peoples.
• Rice is integral to Malagasy cuisine. On average, each Madagascan eats 120 kilograms of rice or varies per year.

Change in Madagascar’s landscape-

• Rice is currently widely cultivated both in the Central Highlands (using paddy production) and in the humid east, where swidden agricultural methods are used (ie, shifting cultivation involving clearing forest for conversion to cropland, usually by burning).
• Slash-and-burn cultivation depleted soils rapidly.
• This caused farmers to abandon land for long fallow periods with further vegetation being cleared at a new location.
• Agriculture primarily led to deforestation on the island. Some 44 per cent of the land covered by native forest in 1953 was deforested by 2014.
• The rate of deforestation has steadily increased.
• It was 99.0 kilohectare per year between 2010 and 2014 and 72.9 Kha/per year from 2014-2020.
• Deforestation in Madagascar reflects global patterns and is primarily driven by the small-scale but widespread practice of swidden agriculture (also known as shifting cultivation; in Madagascar referred to as tavy for rice cultivation in humid and subhumid areas and hatsake for cassava and maize in dry and sub-arid areas).
• Additionally, cash crop production, particularly maize and peanut, had become a major driver of deforestation alongside the production of products for international markets, such as forest-derived vanilla.
• Natural system modifications add to deforestation.
• They threaten 23.2 per cent of vertebrates and 68.9 per cent of plants.
• Some predictions indicate that in the absence of an effective strategy against deforestation, 38 to 93 per cent of forest present in 2000 will be no longer present in 2050.

Madagascar is a biodiversity hotspot-

• Most of the plants, animals, insects and fungi found on the island are found nowhere else in the world.
• Some 56 per cent of the island’s birds, 81 per cent of freshwater fishes, 95 per cent of mammals, and 98 per cent of reptile species are endemic.
• Madagascar, along with India, was part of Gondwana,one of two supercontinents formed millions of years ago.
• South America, Africa and Australia too were part of the great landmass.
• Madagascar latersplitand moved till it reached its present position in the Indian Ocean, separated from Africa by the Mozambique Channel.
• This relative isolation enabled the high endemism among its biota.