Humus Index as an indicator of forest stand and soil properties

Abstract

The Humus Index, based on the visual assessment of topsoil horizons and a classification of humus forms, is a numerical score which can be used as a correlate of stand and soil properties. In oak stands from the Montargis forest (Loiret, France) we observed a good linear relationship of the Humus Index with most parameters describing stand development (age, basal area (BA), height and diameter at breast height of dominants) and soil type (depth of clay horizon). The relationship with parameters describing nutrient availability (exchangeable bases, base saturation) was similarly good but nonlinear. In the studied forest the Humus Index was affected first by stand age and second by soil type. When corrected for age and soil type, data (96 pooled estimates) indicated a slight decrease in the Humus Index (shift towards more active humus forms) in stands converted from old coppices-with-standards when compared with even-aged high forest. #

Assessing Soil Fertility Status of Rehabilitated Degraded Tropical Rainforest

“…The correlation analysis between Soil Organic Matter (SOM) with Total Carbon (TC), Cation Exchange Capacity (CEC) and exchangeable Al showed positively significant difference (p<0.05) for surface soils, indicating that negative charges derived from organic matter and clay minerals play important roles for cation retention capacity and soil fertility status of tropical soils as the case in this study. Ponge and Chevalier (2006) studied at Loiret, France had a positive correlation between the SOM and selected soil parameters (soil acidification and organic matter Science Publications AJES accumulation) which have been repeatedly observed. However, there was not strong correlation (p<0.05) between exchangeable Al with TC and CEC at surface soils.…”

Predicting forest site productivity in temperate lowland from forest floor, soil and litterfall characteristics using boosted regression trees

“…Humus form was determined according to Jabiol et al (2007) and 175 converted to the humus index of Ponge and Chevalier (2006) with values ranging from 1 176 (eumull) to 8 (mor) (Ponge et al 2011), and was determined as an average of 16 177 measurements in each plot. 178…”

Smouldering fire-induced changes in a Mediterranean soil (SE Spain): effects on germination, survival and morphological traits of 3-year-old Pinus pinaster Ait.

“…They vary according to geological, ecological and management factors involved in regeneration, productivity and litter quality of forest stands (Ponge and Chevalier 2006). Fire severity studies recognize the relevant role of organic soil damage in evaluating the magnitude of ecological changes after fires (Keeley 2009).…”

“…Slow carbonization of the organic matter occurs during the smouldering stage and often leads to disappearance of these layers with serious consequences for the future seed bed altering microenvironmental characteristics, moisture, pH and nutrient availability. These factors can affect post-fire recruitment, survival, early growth and plant traits (Lamont et al 1993;Henig-Sever et al 2000;Ponge and Chevalier 2006). Organic layer removal has physiological impacts on plants because nutrients and microbial dynamics are altered (Arévalo et al 1994;García et al 1994).…”