Agricultural Expansion, Soil Degradation, and Fertilization in Portugal, 1873–1960: From History to Soil and Back Again

Abstract

This research explains what happened to agricultural soil fertility during the “Campanha do Trigo” (Wheat Campaign) in Portugal, which began in 1929. It is commonly understood that the excessive expansion of wheat crops during the fascist “Estado Novo” (New State) regime led to the degradation of soils in the southern half of Portugal. This relationship, however, has never been questioned before. This article extends the narrative back into the last half of the nineteenth century in search of the origin of processes that gradually intensified throughout the country. In short, expansion of the cultivated area in association with the inadequate intensification of crop rotations over about 80 years, from the 1870s onward, including in non-wheat areas, strongly accentuated soil erosion and made organic fertilization progressively less effective. These transformations were only partially offset by chemical fertilization. Nitrogen and phosphorus were the key factors in this historical process. Focusing on the cultivation system and soil dynamics allows the successive integration of various kinds of historical evidence and sources. From an environmental question—why did agricultural soil degrade?—this article explores soil degradation over time and space, and assesses its social and biophysical impacts. At the same time, it addresses the history of agriculture in Portugal and its disciplinary foundations.

Social and historical dimensions of wildfire research and the consideration given to practical knowledge: a systematic review

“…Moreover, the history of fire in mountainous areas of post-1950 Portugal is embedded in wider socioecological changes that shaped Portugal's hinterlands. The areas that burned the most between 1990 and 2018, predominantly hills and mountains, largely overlap with (i) the areas most affected by soil degradation in the 1950s after decades of intensive wheat cultivation, and (ii) the wastelands of the late 1800s, which were occupied by shifting agriculture and grazingwhere the use of fire was vital (Carmo et al 2017;Carmo and Domingos 2021). The analytical lines connecting the socioecological changes from the late 1800s to the 1950s and the current fire-prone landscape are yet to be drawn.…”