structural:scholar_edition, stylistic:style_transfer, structural:expansion
Crop failure

Crop failure (also known as harvest failure) is an absent or greatly diminished crop yield relative to expectation, caused by the plants being damaged, killed, or destroyed, or affected in some way that they fail to form edible fruit, seeds, or leaves in their expected abundance.

Crop failures can be caused by catastrophic events such as plant disease outbreaks (such as the Great Famine in Ireland), volcanic eruptions (such as the Year Without a Summer), heavy rainfall, storms, floods, or drought, or by slow, cumulative effects of soil degradation, too-high soil salinity, erosion, desertification, usually as results of drainage, overdrafting (for irrigation), overfertilization, or overexploitation.

In history, crop failures and subsequent famines have triggered human migration, rural exodus, etc.

The proliferation of industrial monocultures, with their reduction in crop diversity and dependence on heavy use of artificial fertilizers and pesticides, has led to overexploited soils that are nearly incapable of regeneration. Over years, unsustainable farming of land degrades soil fertility and diminishes crop yield. With a steadily-increasing world population and local overpopulation, even slightly diminishing yields are already the equivalent to a partial harvest failure. Fertilizers obviate the need for soil regeneration in the first place, and international trade prevents local crop failures from developing into famines.