PMID- 27959897
OWN - NLM
STAT- MEDLINE
DCOM- 20170629
LR  - 20171116
IS  - 1932-6203 (Electronic)
IS  - 1932-6203 (Linking)
VI  - 11
IP  - 12
DP  - 2016
TI  - Impact of Amendments on the Physical Properties of Soil under Tropical Long-Term 
      No Till Conditions.
PG  - e0167564
LID - 10.1371/journal.pone.0167564 [doi]
LID - e0167564
AB  - Tropical regions have been considered the world's primary agricultural frontier; 
      however, some physico-chemical deficiencies, such as low soil organic matter 
      content, poor soil structure, high erodibility, soil acidity, and aluminum 
      toxicity, have affected their productive capacity. Lime and gypsum are commonly 
      used to improve soil chemical fertility, but no information exists about the 
      long-term effects of these products on the physical attributes and C protection 
      mechanisms of highly weathered Oxisols. A field trial was conducted in a sandy 
      clay loam (kaolinitic, thermic Typic Haplorthox) under a no-tillage system for 12 
      years. The trial consisted of four treatments: a control with no soil amendment 
      application, the application of 2.1 Mg ha-1 phosphogypsum, the application of 2.0 
      Mg ha-1 lime, and the application of lime + phosphogypsum (2.0 + 2.1 Mg ha-1, 
      respectively). Since the experiment was established in 2002, the rates have been 
      applied three times (2002, 2004, and 2010). Surface liming effectively increased 
      water-stable aggregates > 2.0 mm at a depth of up to 0.2 m; however, the 
      association with phosphogypsum was considered a good strategy to improve the 
      macroaggregate stability in subsoil layers (0.20 to 0.40 m). Consequently, both 
      soil amendments applied together increased the mean weight diameter (MWD) and 
      geometric mean diameter (GMD) in all soil layers, with increases of up to 118 and 
      89%, respectively, according to the soil layer. The formation and stabilization 
      of larger aggregates contributed to a higher accumulation of total organic carbon 
      (TOC) on these structures. In addition to TOC, the MWD and aggregate stability 
      index were positively correlated with Ca2+ and Mg2+ levels and base saturation. 
      Consequently, the increase observed in the aggregate size class resulted in a 
      better organization of soil particles, increasing the macroporosity and reducing 
      the soil bulk density and penetration resistance. Therefore, adequate soil 
      chemical management plays a fundamental role in improving the soil's physical 
      attributes in tropical areas under conservative management and highly affected by 
      compaction caused by intensive farming.
FAU - Carmeis Filho, Antonio C A
AU  - Carmeis Filho AC
AD  - Department of Crop Science, College of Agricultural Sciences, Sao Paulo State 
      University (UNESP), Botucatu, State of Sao Paulo, Brazil.
FAU - Crusciol, Carlos A C
AU  - Crusciol CA
AD  - Department of Crop Science, College of Agricultural Sciences, Sao Paulo State 
      University (UNESP), Botucatu, State of Sao Paulo, Brazil.
FAU - Guimaraes, Tiara M
AU  - Guimaraes TM
AD  - Department of Crop Science, College of Agricultural Sciences, Sao Paulo State 
      University (UNESP), Botucatu, State of Sao Paulo, Brazil.
FAU - Calonego, Juliano C
AU  - Calonego JC
AD  - Department of Crop Science, College of Agricultural Sciences, Sao Paulo State 
      University (UNESP), Botucatu, State of Sao Paulo, Brazil.
FAU - Mooney, Sacha J
AU  - Mooney SJ
AD  - Division of Agricultural & Environmental Sciences, The University of Nottingham, 
      Sutton Bonington, Nottingham, United Kingdom.
LA  - eng
PT  - Journal Article
DEP - 20161213
PL  - United States
TA  - PLoS One
JT  - PloS one
JID - 101285081
RN  - 0 (Soil)
RN  - 24H4NWX5CO (Kaolin)
RN  - 7440-44-0 (Carbon)
RN  - I38ZP9992A (Magnesium)
RN  - WAT0DDB505 (Calcium Sulfate)
SB  - IM
EIN - PLoS One. 2017 Feb 22;12 (2):e0173011. PMID: 28225834
MH  - Calcium Sulfate/analysis
MH  - Carbon/analysis
MH  - *Crop Production
MH  - Kaolin/analysis
MH  - Magnesium/analysis
MH  - Soil/*chemistry
MH  - *Tropical Climate
PMC - PMC5154518
COIS- The authors have declared that no competing interests exist.
EDAT- 2016/12/14 06:00
MHDA- 2017/07/01 06:00
PMCR- 2016/12/13
CRDT- 2016/12/14 06:00
PHST- 2016/04/04 00:00 [received]
PHST- 2016/11/16 00:00 [accepted]
PHST- 2016/12/14 06:00 [entrez]
PHST- 2016/12/14 06:00 [pubmed]
PHST- 2017/07/01 06:00 [medline]
PHST- 2016/12/13 00:00 [pmc-release]
AID - PONE-D-16-13616 [pii]
AID - 10.1371/journal.pone.0167564 [doi]
PST - epublish
SO  - PLoS One. 2016 Dec 13;11(12):e0167564. doi: 10.1371/journal.pone.0167564. 
      eCollection 2016.