Soil and water conservation in terraced and non-terraced cultivations -
a massive comparison of 50 vineyards
Abstract
Understanding the soil and water conservation (SWC) impact of
steep-slope agricultural practices (e.g. terraces) has arguably never
been more relevant than today, in the face of widespread intensifying
rainfall conditions. In northern Italy, a diverse mosaic of terraced and
non-terraced cultivation systems have historically developed from local
traditions and more recently from the introduction of machinery.
Previous studies suggested that each vineyard configuration is
characterised by a specific set of soil degradation patterns. However,
an extensive analysis of SWC impacts by different vineyard
configurations is missing, while this is crucial for providing robust
guidelines for future-proof viticulture. Here, we provide a unique
extensive comparison of SWC in 50 vineyards, consisting of 10 sites of 5
distinct practices: slope-wise cultivation (SC), contour cultivation
(CC), contour terracing (CT), broad-base terracing (BT) and diagonal
terracing (DT). A big-data analysis of physical erosion modelling based
on high-resolution LiDAR data is performed, while four predefined SWC
indicators are systematically analysed and statistically quantified.
Regular contour terracing (CT) ranked best across all indicators,
reflecting a good combination of flow interception and homogeneous
distribution of runoff and sediment under intense rainfall conditions.
The least SWC-effective practices (SC, CC, and DT) were related to
vineyards optimised for trafficability by access roads or uninterrupted
inter-row paths, which create high upstream-downstream connectivity and
are thus prone to flow accumulation. The novel large-scale approach of
this study offers a robust comparison of SWC impacts under intense
rainstorms, which is becoming increasingly relevant for sustainable
future management of such landscapes.