Presentation on theme: "Impact of legumes intercropping on soil functioning and rubber physiology Set up of an experimental layout in Buriram JEAI ECO-RUBBER."— Presentation transcript:
Impact of legumes intercropping on soil functioning and rubber physiology Set up of an experimental layout in Buriram JEAI ECO-RUBBER
Context Our previous work (Marin et al., 2013, Arunee and Milena 2014) showed that intercropping has an important effect of soil bio-functioning. Legumes seems to have an important impact on soil nutrients, tree physiology (N transfer see work of Clermont dauphin), water soil status, weed prevention etc..
Objective Compare the effect of legume’s intercropping to cassava intercropping on parameters link to soil and plant functioning Select within 3 legumes the most efficient one in terms of N transfer, soil nutrients, soil biodiversity and activities, soil moisture, tree growth etc..
Layout characteristics Tree age: 2 years old Previous crop : Eucalyptus Crop clone: RITT251) Plot size: 25 rai (4,2ha)
Measure of the girth Tree girth size Made by Tum in May 2014
Choice of legumes ! LegumesAdvantageInconvenient Mucuna bracteata Easy to growthPropagation through cuttings (T° and humidity too high in Thailand for seeding) deep-rooted fast growingmoderate drought resistance at the beginning after growing shade tolerance grows fast and covers the field very quickly suppresses all weeds Nitrogen fixing capacity was found to be high and make it available to the main crop impedance to beetle breeding reducing loss of nutrients
Choice of legumes ! LegumesAdvantageInconvenient Calopogonium caeruleum Weed control Increase organic matter nutrient cycling efficiency inhibited erosion reduce fire (in the south) Decrease the day of tapping drought tolerance shed tolerance reduce management and labor expensive Cause of fire (shed leaves in the northeast) Pueraria phaseloides Weed control Cause of fire (shed leaves in the northeast) Increase organic matterNo drought and shed tolerance Nutrient cycling efficiencyHigh fertilizer using Inhibited erosion
Soil sampling 0-5/5-10/ 10-20) Each plots = 6 lines X 12 tree Studied Area Studied Area Studied Area
Measurements (Christian H, Henri R, Claude H. Nok, Supat) Student ? Meteorological records – station Davies or Campbell (here in Bangkok) (Norbert for installation ?) Soil physical parameters (Inter- row + row) – Soil resistivity : Henri in September with ETR – Soil water content sensor Sentec in each row-inter row (6 PVC tubes/ Plot x 24 plots = 144 tubes Mobile sensors (trim pro) : more specific for surface measurements Soil solution (soil trap) (CH) – Hydric potential Tensiometers or psychometrics sensors (Claude H & F.Do) Do we have some available from BNT ? How many we need for the exp ? – Others physical parameters : bulk density, texture ( C.H and LDD Region 5 or LDD Bangkok ? (Nok.) – Chemistry (soil and water solution) pH, Nm, P, K, OM, C,N, (NIRS ? NoK.
Ecophysiological tree measurements (Supat, F. Do, P. Thaler, F. Gay) Student ? NPP : Tree girth and length – KU Equipment for tree length available ? (FG) – Periodicity (each 2 months ?) (FG) Litter fall (litter trap) – Is it necessary ? What model (for FG and PT) LAI (fish-eye) – Could we use LMI-KU equipment ? Who can be involved in the analysis ? (FG) Foliar potential – See if Wattman sensors exist in KKU, are they available for this exp ? (Supat and Fred Do) – Who will be in charge (Supat Student ?) (Supat and FD) Sap Flow – Pb damage the tree, is it necessary now ? (Supat, FD) Mineral content (Supat, F. Do, P.T) – Mg, Ca+, what else ? – Done by Spad ? – Could we use it periodically ?
Measurements at the intercrop (Kiriya and Didier Lesueur) Alain P ? Master Student KKU Wasithi Plant Biomass – Shoot Biomass, Root, Nodules What periodicity ? – LAI ??? (not sure to understand ?) Microbial (need to be more detailled Kiriya) Isolation of N fixing bacteria, PSP (How ? ) PSP Roots ? (Alain P ? )
N2 fixation by the legumes – 15 N natural abundance method using samples of leaves, stems and roots collected each year on the interrank crops – The non legumes interrank crops will be used as non fixing reference plants for the calculations of Ndfa – Biomass of each plant compartment at the period of these samplings will be needed for calculations of N2 stocks N transfert (legumes Tree) (Cathy CD, Kiriya Master student Wasithi ? ) N transfert (legumes Tree) (Cathy CD, Kiriya Master student Wasithi ? )