Rotaciones de cultivos para la rehabilitación de la fertilidad del

Advances in grassland research in the
Mediterranean region of Chile
Talk Outline
Overview agriculture in Chile
Description of the Mediterranean zone
Main problems facing grasslands
Research priorities
Iintroductions of germplasm of annual legumes
Integration of legumes with cereal crops (rotational systems), orchard and
vineyards (cover crops)
Perennial deep-rooted legumes for dryland areas
Outreach to farmers
Economic and environmental challenges
Overview agriculture in Chile
¿A dónde van nuestras
exportaciones?
Países con altos estándares
ambientales y consumidores
cultos y de alto `poder
adquisitivo
Agriculture and forestry export
products
(2011: US$14.191 million)
Other Products
13%
Processed Fruit
and Vegetables
10%
Fresh Fruit 26%
Meat Products 6%
Wine and Spirits
12%
Processed Wood
13%
Cellulose and
Paper 20%
Mediterranean pastures in Chile:
Chilean Agriculture: 25.000.000 has
»Mediterraenan pastures: 2.000.000 has
»Climate: Mediterranean
»Annual rainfall:
» Arid zone: 100 - 200 mm,
•semiarid zones: 200-400 mm, 6-8 months of
drought per year,
•subhumid-humid zones:600-1200 mm and 5-6
months of drought.
MEDITERRAN CLIMATE
IN
CENTRAL - CHILE
Landscape of Chile at 36º of South Latitude
The "Espinal" is located in the eastern slope of the coastal Cordillera and the
not irrigated areas of the Central valley.
Natural vegetation
Most of the 2 million ha of the
secano interior (unirrigated
land )is occupied by a single
tree specie, Acacia caven
(espino), a legume specie
which form a savannah like
agroecosystem, the espinal.
Experimental Site
Environmental degradation of the “espinal”
Herbaceous vegetation:
 is dominated by species of European origin
 there is a low contribution of Legumes and Grasses
of high pastoral value.
 has a low productivity: Average: 1.5 tonDM /ha /year.
Range = 0.4 to 4 ton DM / ha /year.
 support low animal stoking rate: average 1 sheep /ha.
Lotus subpinnatus
Trifoium tomentosum
Adesmia sp.
Acacia caven
Trifolium microdon
Trifolium hirtum
Medicago polimorpha
T. depauperatum
Lupinus microcarpus
T. macraei
T. angustifolium
Melica violacea
Trisetum
spicatum
Nassella exserta
Briza mayor
Stipa manicata
Hordeum murinum
Piptochaetium montevidense
Bromus mollis
Environmental degradation of the
“espinal”
Soil:
Strong deterioration of soil fertility:
Organic mater: <1,4 %
Phosphorus: < 3 ppm
Strong impact of water erosion: 50%
area affected (1,000,000 ha).
Socio-economical characteristic
o Rural population: 350,000 inhabitants.
o Preponderance of small properties
o Low productivity of the agroecosystems.
o Scarce productive options (cereal, meat, vigneyards)
Degradation process
Woodland
fragments
Weel preserved
“Espinal”
Degraded
“Espinal”
Degradation procces
Degraded Espinales:
traditional land use in a
crop rotation: fallow wheat and natural pasture
Good espinales: Traditional land use in
permanent grazing of the natural pasture
Phytomass Production (kg DM/ha/year) of the
natural pasture of the “Espinal” according to the
tree cover level of Acacia caven.
Tree cover
Acacia caven
30 % Acacia caven
Under the tree
Outside the tree
50 % Acacia caven
Under the tree
Outside the tree
80 % Acacia caven
Source : Ovalle, 1986.
Phytomass of the herbaceous layer
kg DM/ha/year
2.780
3.605
2.422
3.274
3.580
3.007
3.966
Research priorities 1
To introduce New germplasm: Species and cultivars of
well adapted annual legumes to the aridity gradient of
central Chile (300 to 900mm)
DM producction (Kg DM ha-1year -1 )of anual
legumes, in vertisols (Interior dryland, 650mm)
Producción de fitomasa (kg ms/ha), de nuevas especies y
variedades en precordillera andina de la VIII Región.
Hualputra
Otras Especies
Paradana
Testigo
M. Barker
Vesiculosum
Mor96
Biserrulas
Casbah
Mor99
Charano
Serradelas
Santorini
Cadiz
Madeira
Tauro
Pitman
Avila
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
Medicago sativa
Plant survival (%)
in four mediterranean
environment of Chile (season 2012-2013)
Research priorities 2
 Integration of annual legumes with cereal crops (rotational
systems), orchard and vineyards (cover crops)
 Influences of grasslands on soil nutrient availability and
microbial ecology, and their role on nutrient cycling in agroecosystems
Descripción del sitio de estudio
Secano Interior
(Mediterráneo sudhúmedo)
Serie de suelos Cauquenes, Alfisol
Precordillera Andina
(Mediterráneo húmedo)
Serie de suelos Santa Bárbara, Andisol
IST: Annual legume+ Legume tree (Tagasaste)
Crop rotation: Medic pasture - wheat
Dry matter of wheat grown after one, two, three or four
years of pasture, in each agroforestry system.
Treatment
Traditional system (TS)
Improved system (IS)
Traditional system+ Tagasaste (TST)
Improved system + Tagasaste (IST)
LPF 1*
LPF 2
(2001)
(2002)
Dry matter (kg ha-1)
11686 a 9580 b
12382 a 11267 a
13397 a 11830 a
12267 a 11397 a
LPF 3
(2003)
LPF 4
(1999)
9230 b
11567 a
9640 b
9790 b
7551 b
10948 a
8007 b
9643 ab
* LPF is the length of the pasture face (1, 2, 3 or 4 years) and in brachets is the actual year.
Establecimiento de experimentos
Ensayo de leguminosas forrajera anual - Cereal
M1
M2
Secano
interior
25 - 37,5 – 37,5
25 - 50 - 25
Precordillera
andina
12,5 - 12,5 – 50 - 25
37,5 - 37,5 - 25
P - T- P – T T- P – P - T
1 año
2 años
P–P–P-T
3 años
Comparisons of shoot dry matter (DM) accumulation &
inputs of fixed N by different legume species (2010)
Andes foothills (Yungay)
Shoot N fixed
Crop
Shoot DM
(tDM/ha)
L. angustifolius
L. albus
P. sativum
V. atropurpurea
9.2 b
11.8 a
8.1 c
3.4 d
Annual Legume
pasture
L1 (1 año)
L1 (2 años)
L1 (3 años)
L2 (1 año)
L2 (2 años)
L2 (3 años)
9.1 d
10.9 c
8.3 e
14.8 b
17.5 a
11.1 c
Shoot N
(kg ha-1)
%Ndfa
(%)
Ndfa
N fijado
-1
(kg ha ) (kg t MS-1 year-1)
219 b
338 a
205 c
78 d
83 c
93 a
89 b
80 d
181 b
316 a
184 b
63 c
20 c
27 a
23 b
19 d
236 bc
268 b
179 c
444 a
463 a
273 b
75 d
83 b
83 b
87 a
80 c
83 b
176 cd
223 bc
149 d
384 a
372 a
228 b
19 b
21 b
18 b
26 a
21 b
20 b
L1 = T. subterraneum + T. incarnatum; L2 = T.subterraneum + T. vesiculosum +
Ornithopus compressus
Comparisons of shoot dry matter (DM) accumulation &
inputs of fixed N by different legume species (2010)
Interior dryland (Cauquenes)
Cereal yield
Wheat tyield trigo (kg grain ha-1)
Secuencia de cultivo
A. sativa (+N) – trigo (+N)
2009
2011
8.003 a (100%)
6.003 a (100%)
A. sativa - Trigo (-N)
M1 (1 año) – trigo (-N)
4.170 c (69%)
7.443 b (93%)
4.858 bc (81%)
M1 (2 años) – trigo (-N)
6.060 a (101%)
M1 (3 años) – trigo (-N)
4.100 c (68%)
M2 (1 año) – trigo (-N)
6.883 c (86%)
4.505 bc (75%)
M2 (2 años) – trigo (-N)
5.128 b (85%)
M2 (3 años) – trigo (-N)
4.598 bc (77%)
M1 = T. subterraneum + T. incarnatum
M2 = T. subterraneum + T. vesiculosum + Ornithopus compressus
CEREAL YIELD
WHEAT YIELD trigo (kg graIn ha-1)
CROP SEQUENCY
2009
2011
A. sativa (+N) – trigo (+N)
3.328 a (100%)
3.393 a (100%)
M1 (1 año) – trigo (-N)
M1 (2 años) – trigo (-N)
2.193 b (66%)
2.200 d (65%)
3.535 a (104%)
M1 (3 años) – trigo (-N)
M2 (1 año) – trigo (-N)
M2 (2 años) – trigo (-N)
M2 (3 años) – trigo (-N)
2.483 d (73%)
2.313 b (70%)
M1 = T. subterraneum + Medicago polymorpha + T. michelianum
M2 = T. subterraneum + Biserrula pelicinus + Ornithopus compressus
2.223 d (66%)
3.113 bc (92%)
1.785 e (53%)
Table 6. Estimates of the proportion of grapevine N derived from the legume cover crops.
Cuadro 6. N derivado desde la leguminosa (%) que es recuperado en plantas de vid
crecidas con o sin cubiertas vegetales.
Cover crop
18-12-2006 08-02-2007
Mean
Leaves
Mixture of early maturing cultivars
Mixture of late maturing cultivars
Stems
Mixture of early maturing cultivars
Mixture of late maturing cultivars
Fruits
Mixture of early maturing cultivars
Mixture of late maturing cultivars
Roots
Mixture of early maturing cultivars
Mixture of late maturing cultivars
12.9 a
12.5 a
14.5 b
27.9 a
13.7 b
20.2 a
19.2 b
12.7 b
19.1 a
17.8 a
19.2 a
15.3 a
6.5 b
12.5 a
39.1 b
55.5 a
Means followed by different letters in the same column differ significantly according to t Student's test (P
 0.05).
Economic and environmental
challenges
 Increase the ecological and economic sustainability of
grazing systems
 Improve grassland diversity, productivity and
persistence
 Rehabilitation of degraded areas → reestablishing
biodiversity and productivity
 Adaptation of plants and agro-ecosystems to the new
challenges imposed by global climate change
Reduction in precipitation
Precipitation has been
decreasing in Chile in
the last century and will
probably continue in the
future due to global
climate change
Outreach to farmers…
New germplasm: Species and cultivars of well adapted
annual legumes to the aridity gradient of central Chile
(300 to 900mm)
Outreach to farmers…
Developing of Commercial Biodiverse Mixtures for
various dry conditions and soil types
Mediterranean 400 mm for semi arid areas
and flat clay soils
Mediterranean 500 mm for hilly granitc soils
Mediterranean 600 mm for sub - humid areas and flat
clay soils
Mediterranean 700 mm for humid areas
and hilly volcanic soils
Outreach to farmers…
Incorporation of the legumes to the crop rotations:
forage and pulses to the farming systems in rainfed
areas.
MUCHAS GRACIAS