The N-P-K soil nutrient balance of Portuguese cropland in the 1950s: The transition from organic to chemical fertilization.

ABSTRACT: Agricultural nutrient balances have been receiving increasing attention in both historical and nutrient management research. The main objectives of this study were to further develop balance methodologies and to carry out a comprehensive assessment of the functioning and nutrient cycling of 1950s agroecosystems in Portugal. Additionally, the main implications for the history of agriculture in Portugal were discussed from the standpoint of soil fertility. We used a mass balance approach that comprises virtually all nitrogen (N), phosphorus (P) and potassium (K) inputs and outputs from cropland topsoil for average conditions in the period 1951-56. We found a consistent deficit in N, both for nationwide (-2.1 kg.ha^-1.yr^-1) and arable crops (-1.6 kg.ha^-1.yr

SUBMITTER: Carmo M 

PROVIDER: S-EPMC5556002 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature