Increasing rainfall, decreasing winds, and historical changes in Santa Catarina dunefields, southern Brazil

Abstract

Morphological and vegetation changes on the Moçambique barrier dunefield system are examined for the period 1938-2002 from aerial photography, and a variety of factors are investigated as possible driving factors. Human factors include a decrease in grazing pressure and tree felling from the early 1960s onwards after 200 years of these activities, and fires. In the 1960s tree planting also took place. During the period 1963 to 1970 there was a marked decline in drift potential (DP -potential sand transport), and then a period of very low DPs (1970DPs ( -1974. This period falls within the time interval when vegetation cover significantly increased by~70% along the Moçambique barrier (from 1956 to 1978). During the 1960s to present, the rainfall increased. Analyses of other transgressive dunefields in Santa Catarina and Rio Grande do Sul states show similar trends so it is likely that climatic factors such as increasing rainfall and decreasing DPs are responsible for driving dunefield changes and vegetation colonization of the barriers.

Coastal dunefields of south Brazil as a record of climatic changes in the South American Monsoon System

“…Florianópolis (Santa Catarina) dunefields (da Silva and Hesp, 2013). Different reasons have been put forward to explain the changes in the coastal dune mobility of these places.…”

Changes in vegetation cover on the Younghusband Peninsula transgressive dunefields (Australia) 1949–2017

“…Climate is often regarded as the main factor for vegetation change in coastal (and desert) dune systems, mainly due to; rainfall variability (Marcomini and Maidana, ; Wolfe and Hugenholtz, ), changes in the wind patterns (Tsoar, ; Tsoar et al, ; Levin, ) or a combination of both (Jones et al, ; Martinho et al, ; Miot da Silva et al, ; Miot da Silva and Hesp, ). However, a number of other factors have been considered as drivers coastal vegetation changes.…”

Geomorphological changes in an arid transgressive coastal dune field due to natural processes and human impacts

“…Geomorphological changes that occur within transgressive dune systems are associated with both natural causes, especially related to changes in climatic characteristics (Martinho et al ., ; Levin, ; Miot da Silva et al ., ; Miot da Silva and Hesp, ), and also to human actions (Alonso et al ., ; Granados Corona et al ., ; Hesp, ; Tsoar and Blumberg, ; Kutiel et al ., ; Levin and Ben‐Dor, ; Mitasova et al ., ; Carretero et al ., ), or a combination of both (Piotrowska, ; Marcomini and Maidana, ; Pye et al ., ).…”