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| Titel |
Evaluating the soil physical quality under long-term field experiments in Southern Italy |
| VerfasserIn |
Mirko Castellini, Anna Maria Stellacci, Massimo Iovino, Michele Rinaldi, Domenico Ventrella |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250149832
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| Publikation (Nr.) |
 EGU/EGU2017-14225.pdf |
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| Zusammenfassung |
| Long-term field experiments performed in experimental farms are important research tools to
assess the soil physical quality (SPQ) given that relatively stable conditions can be expected
in these soils. However, different SPQ indicators may sometimes provide redundant or
conflicting results, making difficult an SPQ evaluation (Castellini et al., 2014). As a
consequence, it is necessary to apply appropriate statistical procedures to obtain a minimum
set of key indicators.
The study was carried out at the Experimental Farm of CREA-SCA (Foggia) in
two long-term field experiments performed on durum wheat. The first long-term
experiment is aiming at evaluating the effects of two residue management systems
(burning, B or soil incorporation of crop residues, I) while the second at comparing the
effect of tillage (conventional tillage, CT) and sod-seeding (direct drilling, DD). In
order to take into account both optimal and non-optimal soil conditions, five SPQ
indicators were monitored at 5-6 sampling dates during the crop season (i.e., between
November and June): soil bulk density (BD), macroporosity (PMAC), air capacity
(AC), plant available water capacity (PAWC) and relative field capacity (RFC).
Two additional data sets, collected on DD plot in different cropping seasons and in
Sicilian soils differing for texture, depth and land use (N=140), were also used
with the aim to check the correlation among indicators. Impact of soil management
was assessed by comparing SPQ evaluated under different management systems
with optimal reference values reported in literature. Two techniques of multivariate
analysis (principal component analysis, PCA and stepwise discriminant analysis,
SDA) were applied to select the most suitable indicator to facilitate the judgment on
SPQ.
Regardless of the considered management system, sampling date or auxiliary data set,
correlation matrices always showed significant negative relationships between RFC
and AC. Decreasing RFC at increasing AC is expected as both indicators depends
on soil water contents at saturation and field capacity. Our results reinforce the
suggestion that one of the two indicators can be neglected (Cullotta et al., 2016) even
if further investigations are necessary to choose the most accurate and/or widely
applicable indicator since different optimal ranges were suggested in literature. A
positive significant correlation was also generally found between PMAC and AC. PCA
analysis identified RFC and AC as the main indicators that explain most of the
data variation. When the data collected at the different sampling dates were pooled
together, in both experiments the first principal component explained the highest
proportion of total variance (67.9% and 81.5%, respectively for residue management
and tillage) and RFC showed the highest loadings, followed by AC and PMAC.
SDA provided consistent results and RFC was selected as the main variable to
assess the effects of tillage. Conversely, the residue management had no effect on
SPQ as indicated by negligible differences between indicators. Finally, our results
suggest that RFC always reached optimal and steady values between April and
June.
*The work was supported by the projects “STRATEGA, Sperimentazione e
TRAsferimento di TEcniche innovative di aGricoltura conservativA”, financed by
Regione Puglia - Servizio Agricoltura, and “DESERT, Low-cost water desalination
and sensor technology compact module” financed by ERANET-WATERWORKS
2014.
References
Castellini, M., M. Niedda, M. Pirastru, and D. Ventrella. 2014. Temporal changes of soil
physical quality under two residue management systems. Soil Use Management. 30:423–434.
doi:10.1111/sum.12137
Cullotta, S., V. Bagarello, G. Baiamonte, G. Gugliuzza, M. Iovino, D.S. La Mela Veca, F.
Maetzke, V. Palmeri, and S. Sferlazza. 2016. Comparing Different Methods to Determine
Soil Physical Quality in a Mediterranean Forest and Pasture Land. Soil Sci. Soc. Am. J.
80:1038-1056. doi:10.2136/sssaj2015.12.0447 |
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