Tissue density determines the water storage characteristics of crop residues

Abstract

Background and aims The water storage properties of plant residues play an important role in the regulation of water retention and water transport in no-till agricultural soils. The objective of this work was to understand how the characteristics of crop residues determine their water absorption and retention properties. Methods A range of eleven undecomposed crop residues and maize stem residue of different particle sizes at three stages of decomposition were characterized regarding their physical and chemical features. Water immersion for varying periods of time was used to determine the kinetics of water absorption and the maximal water storage for each type of residue. Results The immersion time required to reach an equilibrium moisture content varied greatly according to the residue type, ranging from 6 to 30 h at 20°C. The maximal water content ranged from 1.28 to 3.81 g H 2 O g −1 dry residue for undecomposed residues and increased with increasing decomposition. The proportions of cellulose, hemicellulose and lignin in the plant cell walls did not explain the water storage capacities. Differences in porosity, resulting from different tissue densities and the creation of pores during decomposition, were highly correlated with differences in water storage properties. Conclusions The tissue density of plant residues, which can be inferred from simple characteristics of residue mass and volume, is a relevant criterion for explaining the maximal water storage capacity of plant residues.

Improving maize production through nitrogen supply from ten rarely-used organic resources in Ghana

“…While these contrasting results do not undermine the applicability of substrate initial N concentrations and C/N ratio as plant litter quality indicators, they imply the necessity for prudent decision making in selecting plant residues for soil fertility improvement based on multiple plant and soil factors. It is therefore reasonable to assume that unlike the initial N concentrations of the plant residues and their C/N ratios, their decomposition and N mineralization may be related to: (1) different decomposer communities that may have developed on the plant residues based on their intrinsic qualities (Cobo et al 2002); (2) other plant quality variables such as lignin, polyphenol, hemicellulose concentrations and their ratios with N; (3) C/N ratio of soil; as well as (4) the water retention capacity of plant residues which although unassessed in this study have been shown to influence plant residue decomposition and N mineralization (Palm et al 2001;Iqbal et al 2013;Makkonen et al 2013). Based on the results on N mineralization, leaf biomass application of T. diversifolia, G. sepium, L. leucocephala and S. spectabilis are expected to improve soil N availability and subsequent uptake by crops for increased biological yield.…”

Dynamiques de décomposition des résidus de cultures sur des exploitations pratiquant l'agriculture de conservation en région Grand Est, France

“…Pourtant, nous avons travaillé avec des quantités variables de résidus de plantes, ayant des caractéristiques différentes, et sur des exploitations et situations climatiques différentes au moment des récoltes et au cours des cinétiques de décomposition. Iqbal et al (2013) ont montré sur les tiges de ces mêmes espèces une différence importante de la composition chimique (par exemple, le rapport fraction soluble : fraction lignine égale à 1,24 pour le blé et 3,92 pour le maïs) et des propriétés physiques (par exemple, la densité des tiges de 0,35 g cm À3 pour le blé et 0,10 g cm À3 pour le maïs). Or, ces cinétiques se superposent selon un ajustement proportionnel à la biomasse initialement présente, selon des jours « normalisés » sur le seul critère de la température de l'air.…”

Soil Moisture Variation in a Farmed Dry-Hot Valley Catchment Evaluated by a Redundancy Analysis Approach

“…Under dry conditions, when land was fallow after harvesting, the topographic factor became important in determining soil moisture content. However, a residual cover crop remained after harvesting, and any type of conservation tillage may also affect soil moisture [68][69][70][71].…”