Cover crops in vineyards and olive groves in Mediterranean semi-arid environments

Transcription

1 Cover crops in vineyards and olive groves in Mediterranean semi-arid environments Maria Jose Marques Universidad Autónoma de Madrid. Spain Mediterranean semi-arid environments Land use and soil vulnerability of permanent crops: olives and vines Soil tillage versus cover crops Benefits: erosion, runoff, soil structure Constraints: soil moisture, productivity Current implementation of scientific knowledge

2 Basic maps for EuroPEARL Higher temperature Lower rainfall Image source: Pearson Education, Inc.

3 17997 Area (x 1000 ha) Other Fallow land TUGAL SPAIN ITALY Source: FAOSTAT. GREECE date of searching: Dec Forest area Agricultural Area 40-62% Total agricultural area Almonds Grapes Olives

4 Land management practice: Soil tillage Olive groves > y Planted in hills and rolling planes years Almond trees Vineyards y The soil remains bare during the whole year They are permanent crops

5 Villaconejos, Madrid, Spain A large proportion of the land s surface is denuded. Bare soil ranges from 75 to 85% Campo Real, Madrid, Spain

6 What are the consequences of this type of land management? Slope 5-15 % Soil depth (<30 cm) Available water (rainfall mm/y) Low organic matter (< 2%) and nutrients Droughts Occasional high intensity rainstorms Aranjuez, Madrid, Spain

7 Wind erosion Water erosion Soil crust Photo: C. Ramos Autumn, 2012 Andalusia, Spain Runoff and floods

8 Titulcia, Madrid, Spain Losses: soil, nutrients, water Low productivity Soil degradation Land abandonment Desertification Aranjuez, Madrid, Spain

9 How much soil is lost in these orchards? Photo: C. Ramos up to 200 t ha -1 y -1 (Martínez-Raya et al., 2006) < 10 t ha -1 y -1 (Fleskens & Stroosnijder, 2007) More than 1 t ha -1 y -1 can be considered non tolerable in vulnerable soils if the loss is maintained for several decades (Verheijen et al., 2009 )

10 3 rd October 2007, 40 mm day -1. Heavy rainfall, I 10 : 52 mm h -1 Average slope 10% Land management: reduced tillage rill + interill erosion: 68 t ha -1 rill + interill erosion: 4 t ha -1 1 ha with contour plowing (100 m long) 16 1 m 2 erosion plots interill erosion: 0.6 t ha ha plowed along the slope (250 m long) Bienes R. and Marques MJ Rill and interril erosion produced by a single-storm event in an olive grove in central Spain. In Proceedings of EUROSOIL 2008 Control No A-804

11 considering 1.3 g cm -3 soil bulk density 4 t ha mm 65 t ha -1 5 mm 18 cm 50 cm

12 There are various systems for reducing erosion no tillage, minimum tillage, conservation tillage... herbicides terraces inert covers cover crops in the inter-rows of olives and vines

13 The use of cover crops is not new Hunter valley, SW Australia 750 mm y -1 (Loughran y Balog, 2006) France 650 mm y -1 (Corbane et al., 2008) to 1000 mm y -1 (Blavet et al., 2009) Napa Valley, CA mm y -1 (Battany y Grismer, 2000) Italy mm y -1 (Gristina et al.; 2005; Novara et al., 2011)

14 What happens if rainfall is below 500 mm? Spontaneous vegetation mowed in spring 1. Belmonte de Tajo, Madrid, Spain Typic Calcixerepts 12 % SLOPE Brachypodium distachyon permanent Using vegetation in rainfed vineyards ( mm rainfall y -1 )

15 What happens if rainfall is below 500 mm? Secale cereale (rye) mowed in spring Brachypodium distachyon permanent 2. Campo Real, Madrid, Spain Calcic Haploxeralf 14% SLOPE Using vegetation in rainfed vineyards ( mm rainfall y -1 )

16 What happens if rainfall is below 500 mm? Hordeum vulgare (barley) mowed in spring 3. Villaconejos, Madrid, Spain Typic Calcixerepts 8 % SLOPE Brachypodium distachyon permanent Using vegetation in rainfed vineyards ( mm rainfall y -1 )

17 9 EROSION PLOTS per vineyard (3 per treatment) 2 m 2 (4 m x 0.5 m) Sediment yield Runoff 2 moisture sensors at 10 and 35 cm depth Comparisons between treatments Soil loss Runoff Soil moisture

18 Marques, MJ, García-Muñoz, S., Muñoz-Organero, G., Bienes, R Soil conservation under grass cover in hillside vineyards under mediterranean climate. Land Degradation and Development. 21(2): SOIL LOSS AFTER HEAVY SORM 43 mm during 4 hours (20 May 2007). I 10 = 155 mm h -1 Permanent sown crop: Brachypodium distachyon Mowed crop: Secale cereale Reduced tillage 19 ± 14 g m ± 26 g m -2 >787 ± 564 g m -2 8 t ha -1

19 SOIL LOSS accumulated soil loss twoyear period Vineyard 1. Belmonte. 23 rainfall events Reduced tillage 35 g m -2 y -1 B. distachyon 17 g m -2 y -1 (58% less than tillage) Spont. vegetation 24 g m -2 y -1 (34% less than tillage) Vineyard 2. Campo Real. 24 rainfall events Reduced tillage 36 g m -2 y -1 B. distachyon 3 g m -2 y -1 (93% less than tillage) Rye 16 g m -2 y -1 (57% less than tillage) Vineyard 3. Villaconejos. 28 rainfall events Reduced tillage 178 g m -2 y -1 B. distachyon 27 g m -2 y -1 (86% less than tillage) Barley 32 g m -2 y -1 (82% less than tillage)

20 SOIL ORGANIC MATTER (%) in the topsoil (0-15 cm) Vineyard SOM (%) T (years) cover Vineyard 2. Campo Real Vineyard 2. Campo Real Vineyard 3. Villaconejos y 3 y 2 y B. distachyon S. cereale H. vulgare No differences were found in Vineyard 1. Belmonte. M. Ruiz-Colmenero, R. Bienes, D.J. Eldridge, M.J. Marques Vegetation cover reduces erosion and enhances soil organic carbon in a vineyard in the central Spain. Catena. DOI: /j.catena

21 Matric Potential PWP 4.2 Water holding capaciy Micropores. Water retention. Not available for plants DRY SOIL FC 2.5 Available Water for plants Macropores. Water infiltration and circulation WET SOIL ~ from 12% to 23% 11% ~ from 7% to 23% 16%

22 WATER RETENTION CAPACITY. MATRIC POTENTIAL. After 4 years of treatment undisturbed soil samples (Richards, 1941) n=9 Van Genutchen Model (1980) θ h = θ r + (θ s - θ r ) [1/(1+(αh)n]m R² > 0,90 M. Ruiz-Colmenero, R. Bienes, D.J. Eldridge, M.J. Marques Vegetation cover reduces erosion and enhances soil organic carbon in a vineyard in the central Spain. Catena. DOI: /j.catena

23 ACCUMULATED RUNOFF (mm) during two years Vineyard 1. Belmonte Spon. Veg. Red. Tillage B. distachyon Vineyard 2. Campo Real Rye Red. Tillage B. distachyon Vineyard 3. Villaconejos Barley Red. Tillage B. distachyon Ruiz-Colmenero, S; Bienes R.; Marques MJ Soil and water conservation dilemmas associated with the use of green cover in steep vineyards. Soil & Tillage Research 117,

24 Infiltration (mm h -1 ) INFILTRATION after 4 years of treatments Single ring test (USDA, 2001) n= Kostiakov model (1932 )(K = cx -b ) B. distachyon y = 152 x ; R² = 0.94 S. cereale y = 141 x ; R² = 0.96 Laboreo Red. tillage y = 118 x -0,54 ; R² = 0, ± 63 mm h ± 85 mm h ± 43 mm h Time (hours) Lab. Reduced tradicional tillage B. distachyon S. cereale

25 COSTS the costs of tillage are higher than those for temporary cover crops. (OLIVERO PROJECT) Tillage ha -1 Cover crops ha -1 the costs of seeds Spontan. vegetation 0 /kg Rye and Barley 70 kg ha /kg B.distachyon 40 kg ha -1 6 /kg de Graaf, J, Duarte, F., Fleskens, L., de Figueiredo T The future of olive groves on sloping land and ex-ante assessment of cross compliance for erosion control. Land Use Policy 27,

26 PRODUCTION kg vine -1 y -1 (n=50, average two harvests) Vineyard 1. Belmonte Vineyard 2. C. Real Vineyard 3. Villaconejos 8 a a a 7 a a ab 6 a b 5 b Till. B.d. Spont.vg. Till. B.d. Rye Till. B.d. Barley SOIL MOISTURE m 3 m -3 WATER CONSUMPTION OF VINES Month 85% % 85%

27 Balance of benefits Cover crops 1. Control erosion 2. Prevent runoff 3. Promote infiltration 4. Increase SOM 5. Improve soil structure 6. Are cheaper Quality? Tillage practices 1. Increase production * (short term) 2. Maintain soil moisture (development phase) * Not in all the treatments

28 THE OPINION OF FARMERS. Survey 64 vinegrowers Regions: Madrid & Castilla La Mancha. Spain Are you worried about soil erosion? Yes No DK/DA 10% Do you receive Government financial aid to avoid erosion? 3% 13% Yes No DK/DA 84% 10% 80% Marques MJ, Velasco A., Ruiz-Colmenero M., Cuadrado, J., Bienes R Sustainable Land Management in steep Vineyards in central Spain. The vision of Land Users. In: Action of rain and wind in soil degradation processes. Donald Gabriels & Jan Vermang (Eds.). UNESCO Chair of Eremology. Gent. Belgium. I'm going to retire I'm satisfied with my crop Weeds Would you change to cover crops since they promote soil conservation? 17% 49% DK/DA Climate too dry Why? 34% Decrease production It needs specific maintenance Yes No DK/DA Water competition I need more information

29 Land management and soil maintenance (%) in Spain. Source: Ministerio de Agricultura, Alimentación y Medio Ambiente. Statistics Section SGT traditional tillage reduced tillage spontaneous cover 6 seed cover 0.8 inert cover no maintenance no tillage no information Vineyards Tillage 88% Olive groves Tillage 67%

30 Policy measures Agri-environment measures were introduced in the late 1990s to address this problem, especially after decoupling with Single Payment Scheme (EC, 2005). The farmers had to comply with several requirements, for example, keeping a vegetation cover between trees and natural vegetation on the land borders The implementation is very irregular (between 5 and 25%) This agri-environment measure was not a success

31 Possible reasons have been suggested Structural factors? the soil conditions (the more soil degradation the less probability to apply for the measure because costs increase). farmers may be unsure with continuing to farm for the time of the agri-environment commitment Insufficient financial support? (basic payments ~ 250 ha -1 y -1 ) In Spain there is a deficient technical support and advisory services to farmers. The scientific knowledge is not properly transmited to the land users.

32 Than you for your attention