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World farm-gate greenhouse gas emissions by activity. Soil degradation is the decline in soil quality that can be a result of many factors, especially from agriculture. Soils hold the majority of the world's biodiversity, and healthy soils are essential for food production and adequate water supply. [53]
A common theme of agricultural recessions, as opposed to famines and crop failures was that they tended to be linked to market conditions, often the opening up of new areas of production and the ability to bring crops into previously markets that had previously protected either by high transport costs (as in the nineteenth century) or by a war ...
Agriculture contributes greatly to soil erosion and sediment deposition through intensive management or inefficient land cover. [32] It is estimated that agricultural land degradation is leading to an irreversible decline in fertility on about 6 million ha of fertile land each year. [33]
This global decline is dominated by negative impacts in already warm countries, since agriculture in cooler countries is expected to benefit from warming. [27] However, this does not include the impact of changes in water availability, which can be far more important than the warming, whether for pasture species like alfalfa and tall fescue ...
Agricultural expansion describes the growth of agricultural land (arable land, pastures, etc.) especially in the 20th and 21st centuries.. The agricultural expansion is often explained as a direct consequence of the global increase in food and energy requirements due to continuing population growth (both which in turn have been attributed to agricultural expansion itself [1] [2]), with an ...
Intensive farming often leads to a vicious cycle of exhaustion of soil fertility and a decline of agricultural yields. [94] Other causes of land degradation include for example deforestation, overgrazing, and over-exploitation of vegetation for use. [95] Approximately 40 percent of the world's agricultural land is seriously degraded. [96]
Earthquakes may have contributed to decline of several sites by direct shaking damage or by changes in sea level or in water supply. [28] [29] [30] More generally, recent research pointed to climate change as a key player in the decline and fall of historical societies in China, the Middle East, Europe, and the Americas.
This increased level of poverty eventually causes depopulation by decreasing birth rates. If asset prices keep increasing, social unrest would occur, which would likely cause a major war, revolution, or a famine. Societal collapse is an extreme but possible outcome from this process. The theory posits that such a catastrophe would force the ...