Soil redistribution and budget in rain-fed vineyards: from field to landscape unit

Manuel López-VicenteDept. of Soil and Water,Soil Management and Global Change Group,Experimental Station of Aula Dei, EEAD-CSIC, Zaragoza, Spain

Soil Erosion Modelling WorkshopJRC Ispra, Italy20-21-22 March 2017BLOCK B: Small scale soil erosion modelling

Woody crops

Vineyards in the World & Europe:- Spain: 1.02 million hectares planted- China: 799,000 hectares- France: 792,000 hectares- Italy: 690,000 hectares- Turkey: 502,000 hectares- USA: 425,000 hectares

Introduction

Fruit groves (vineyards, almond, olive, orange, coffee, tea, etc.) and forest plantations mean a significant percentage of the total cultivated soils in the World.

These perennial crops represent about 16% of the agricultural land in the Mediterranean area(FAO, 1998) and are of a great economic importance (Infante-Amate, 2012. Rural History 23 (2), 161-184).

Introduction

Overland flow in woody cropsPermanent features, such as the trunks of the woody crops, and the grooves and rows that follow

straight lines, mainly control overland flow paths, especially in those areas with low and moderate slope steepness (López-Vicente et al., 2016. Catena 147, 125-137).

Introduction

Effect of Scale and Input ResolutionThe raster DEM resolution has influence on simulating hydrological features and has serious

implications to the results of hydraulic models (Ali et al., 2015. HESS 19, 631-643).

In agricultural catchments, the use of optimal DEM resolutions is necessary for defining critical source areas of sediments as well as to capture microtopographic features (Thomas et al., 2017. Int. J.

Applied Earth Obs. Geoinf. 54, 38-52).

METHODS:o SR: Soil Roughnesso CI: Convergence Indexo HC: Index of Hydrological Connectivity

ANALYSIS:o Effect of Scale and DEM resolution: from field to landscape unito Sediment Budget & Validation

OBJECTIVE:

Objective & Methods

To assess the effect of six DEM resolutions (0.03, 0.05, 0.1, 0.2, 0.5 and 1 m) on:(1) Surface microtopography,(2) Hydrological connectivity and(3) Soil redistribution

in a Mediterranean agricultural sub-catchment (27.4 ha).

- Soil in the rows remain ca. 13 cm raised related to the soil in the inter-row area- Several ephemeral gullies in the cereal fields and vineyards- Three depositional areas at the bottom of three fields

Study area ‘Barbastro’ site: 15,039 grapevines in 147 lines

Soil Roughness: standard deviation of point elevations

Methods & Results

1 m 0.2 m 0.05 m

Convergence Index: smooth horizontal curvature

Methods & Results

1 m 0.2 m 0.05 m

HydrologicalConnectivity:Borselli’s index (updated)

Methods & Results

-13-12-11-10

-9-8-7-6-5-4-3-2-10

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

Hydr

olog

ical

Con

nect

ivity

(ind

ex)

DEM resolution (m)

HC-mean

HC-min

HC-max

Analysis

Effect of Scale and DEM resolution:from FIELD to LANDSCAPE UNIT

-1,6

-1,4

-1,2

-1,0

-0,8

-0,6

-0,4

-0,2

0,0

0

5

10

15

20

25

30

35

40

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

Conv

erge

nce

Inde

x (%

)

Soil

Roug

hnes

s (m

m)

DEM resolution (m)

SR

CI

Linked to the vertical component of the agricultural(microtopography and tillage) and landscape components

Sediment Budget:

Analysis

Validation: Sediment Traps

-20

-15

-10

-5

0

5

10

15

0

5

10

15

20

25

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

Conv

erge

nce

Inde

x (%

)

Soil

Roug

hnes

s (m

m)

DEM resolution (m)

SR-EphemeralGullies SR-DepositionalAreas

CI-EphemeralGullies CI-DepositionalAreas

-9

-8

-7

-6

-5

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

Hydr

olog

ical

Con

nect

ivity

(ind

ex)

DEM resolution (m)

HC-EphemeralGullies HC-DepositionalAreas

Events with different magnitude: Identification of activated areas:

from field to landscape units

THANK YOU FOR YOUR ATTENTION

Questions?