Page 150 - Agroforestry system - book inner (final corrected) - 9.-3-21_Neat

National level e-symposium on “Agroforestry system for augmenting livestock
productivity and empowering resource poor rural farmers”

S 4 – 1

Productivity and Carbon Storage Potential of Calliandra Hedgerows underneath Coconut
Plantation in Humid Tropics of Kerala

Asha K. Raj, Jilna Joy, T.K. Kunhamu and V. Jamaludheen
College of Forestry, Kerala Agricultural University, KAU (PO), Thrissur-680 656, Kerala.
Corresponding author’s Email: ashajayamohan@gmail.com

Introduction
Scarcity of quality fodder, acute crude protein deficits and high cost of concentrate feeds are the major
hindrances to profitable livestock production in Kerala, where feed alone comprises 60 to 70 per cent of the
production cost. Hedgerow planting of protein rich fodder trees in blocks, known as “protein banks”, in the
available interspaces of existing coconut gardens is a possible option for enhancing quality forage production
in land crunch states like Kerala.

Among fodder trees, Calliandra (Calliandra calothyrsus Meissn.), a leguminous tree, by virtue of its
nutritive foliage with good palatability, fast growth, ability to withstand pruning and vigorous coppicing, is
found to be a promising species for hedge row planting in humid tropical regions (Sagaran et al., 2018). In
addition to fodder production, the integration of fodder trees also offers ecosystem services like carbon storage
and associated climate change mitigation. Fast growing trees have higher carbon accretion efficiency owing
to their vigorous growth and biomass production within short periods (Rocha, 2017), wherein carbon fixation
rates are in turn influenced by stand management practices like density regulation and harvest schedules. In
this context, a field study was conducted to assess the influence varying tree densities and harvest intervals
on forage and crude protein yield, and carbon storage potential of three –year old calliandra hedgerows
underneath coconut plantation.
Materials and methods

The study was conducted at Instructional Farm, College of Horticulture, Vellanikkara, Thrissur during
2014-17. Calliandra was intercropped under varying levels of tree densities (27,777; 22,222 and 17,777
plants ha ) in the interspaces of coconut (Variety- West Coast Tall; age 35 years; spacing 7.6 x 7.6 m) and
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harvested at different pruning intervals (8, 12 and 16 weeks), following factorial randomized block design
replicated thrice.

Annually six, four and three harvests were taken from calliandra stands for intervals of 8, 12 and 16
weeks respectively. The trees were harvested leaving a stubble height of 1m. The yield observations were
collected for three years and dry forage and crude protein yield were estimated following standard procedures
and scaled to hectare basis.

The harvested fodder biomass from calliandra over three year period and the left over woody stem and
root biomass at the end of the third year were estimated to calculate the carbon stocks in calliandra by using the
loss-on-ignition method in muffle furnace. Carbon stocks in coconut palms were estimated nondestructively
by estimating the biomass and compiling carbon content in the coconut bole, leaves and nuts excluding roots.
Soil samples were collected from five soil depths (0-20 cm, 21-40 cm, 41-60 cm, 61-80 cm and 81-100 cm)

Institute of Animal Nutrition, Centre for Animal Production Studies, TANUVAS
National Bank for Agriculture and Rural Development 131