Evaluation of Rice Straw Yield, Fibre Composition and Collection Under Mediterranean Conditions

Abstract

Rice straw remains almost unutilised in the majority of cases and is usually burned. Data on rice residue production under European conditions are extremely limited. A detailed assessment of rice biomass yield, partitioning and straw collection was carried out in Spain. Eleven commercial rice varieties were evaluated in 2015, and two baling trials were performed in 2014 and 2015. The average straw yield was 9.7 t·ha−1. Straw yield, biomass partitioning indices and fibre composition varied significantly according to rice variety. Straw to grain ratio and harvest index were 1.00 and 0.50 on average for rough grain, and 1.25 and 0.41 for husked grain. Biomass partitioning indices significantly correlated with grain yield. Mean content of cellulose, hemicellulose, lignin and ash of rice straw was 32.5%, 19.8%, 6.5% and 13.7%, respectively. Straw amount of less than 3.0 t·ha−1 can be collected during the baling trials. Rice straw could represent an eco-friendly source of lignocellulosic biomass in Europe, however, in order to achieve this, baling machine improvements and special crop management should be carried out.

Evaluation of Dry Matter Intake and Average Daily Gain of Beef Cattle in Samarinda City

“…Rice is the staple food commodity for Indonesian citizens. Rice grain milling (husks, bran) turns out by-products such as straw and residue [36]. The amount of unhusked rice produced in the East Kalimantan Province in 2018 and 2019 was 262,773.88 tons and 253,818.37 tons, respectively [7].…”

“…However, this action creates new and more serious problems such as air, soil, and environmental pollution [10]. Air pollution can occur because the burning of straw will produce particulate matter in the air and release CO 2 into the atmosphere [36]. The nutritional content of rice straw varies from region to region, so the quantity of its uses as feed varies widely.…”

An Assessment on the Technical and Economic Feasibility of Mechanized Rice Straw Collection in the Philippines

“…The rice variety was not duly considered in assessing the rice straw yield due to the mixture of varieties that were planted in the fields and in piled rice straws that were mechanically threshed. Variety is one of the factors that determine the amount of biomass residue in the field, aside from the cutting height of the stubble, which affects rice straw yield, as reported by [7,39]. The baling rate, which is also described as effective field capacity [40], is the actual amount of rice straw cFollected by baler per unit time.…”

The main drivers of methane emissions differ in the growing and flooded fallow seasons in Mediterranean rice fields

“…Plant d and panicle density was assessed by IRTA staff by counting plants and panicles in 10 to 15 delimited subareas of 0.25 m 2 each, distributed along a diagonal transect of the field. Grain yield of the current and preceding season was used as a proxy of the rate of straw input, assuming a mean harvest index of 0.5 (Matías et al 2019).…”