TERCEIRÂ REUNIÄO BRASILEIRA CIENCIA DO SOLO

122 ANAIS DA TERCEIRA REUNIÂO BRASILEIRA DE CIÊNCIA DO SOLO
6 — Conclui-se, além disso, que, maior o estado de saturaçâo
do complexo, isto é, maior o valor de V, maior sera a depressäo de
( H- ). Este fato, constatado por PEECH e BRADFIELD (13) através de
titulaçôes condutométricas de argilas hidrogenadas, vem indicar que
sômente em solos de elevada saturaçâo pode o salóide sódico agir de
modo considerâvel como urn depressor da atividade de hidrogeniontes
em suspensôes de solo. Hâ assim, consistência qualitativa entre a correlaçâo
por nós encontrada e a interpretaçâo da hidrólise do complexo
scdico dentro da teoria de MATTSON.
V — CONCLUSÄO
Hâ uma correlacäo linear, positiva e significante, entre o ......
pH (1 : 25) e o grau de saturaçâo do complexo adsortivo em .sódio
permuta vel, 100. NA/T, para solos aluviais da regiâo^semi-ârida do
Nordeste brasileiro. •
VI — CONCLUSION
There is a linear, positive and significant correlation between the
pH (1 : 2,5) and the ratio 100.Na/T (adsorbed Na to total adsorption
capacity) for a group of semi-arid alluvial soils (brazilian Northeast).
VII — BIBLIOGRAFIA
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