Land use and soil carbon accumulation patterns in South African savanna ecosystems

Soil surface properties in Mediterranean mountain ecosystems: Effects of environmental factors and implications of management

“…The effect of the type of vegetation is seen in a significant decrease of fungic activity in horizons under reforested forest compared to natural forest and shrubs which have similar values. The presence of fungal-derived pigments in forest soils has been described in a wide variety of environments, from Mediterranean mountains similar to the subject of this study (Oyonarte et al, 1994) to semiarid environments (Aranda and Oyonarte, 2005) and temperate zones (Zancada et al, 2003), and tend to disappear in altered soils, which could be due to significant changes in the structure of microflora in the soil (Almendros et al, 2005). Thus, this decrease of fungic activity observed in soils under reforestation of Pinus sp.…”

Effect of soil type and management (organic vs. conventional) on soil organic matter quality in olive groves in a semi-arid environment in Sierra Mágina Natural Park (S Spain)

“…Weak values in cultivated soils can be attributed to low fungal activity (Almendros et al, 2005), which is the case in this study, and could be due to significant changes in the structure of the soil microflora. However, a trend toward accumulation of perylenequinone chromophors was observed in samples OEM1, OCM1 and SM, the concentration of which is an indicator of the extent of fungal metabolism in HA formation processes (Almendros et al, 2005). This could be pointing to increased complexity of the trophic system reflected in the chemical biodiversity of the SOM composition in these soils.…”

Soil organic matter quality in three Mediterranean environments (a first barrier against desertification in Europe)

“…The visible derivatographic spectroscopy of HA studied highlights valleys near 620 nm, 570 nm and 528 nm (D 620 , D 570 and D 528 ). These diagnostic spectral bands suggest the presence of perylenequinonic pigments derived from fungi (Oyonarte et al, 1994;Almendros et al, 2005). Table 3 shows the mean intensities of these bands in which differences may be observed, although not significant when grouping the samples by sampling zone, and which are generally higher in the basic mediums in SC and CG.…”

“…Finally, the in vitro respiratory activity of soils (soil C mineralization potential) was determined by estimating the CO 2 released from soil samples moistened to 60% of their water holding capacity at 24±1ºC, measured periodically for a period of 40 days with a Carmhograph-12 (Wösthoff) gas analyser (Almendros et al, 2005); the results referred to total mineralisation coefficient, taking into account that each soil had a different organic matter content, and was defined as milligrams of carbon released per 100 g of soil carbon per day. Range (minimum-maximum), Mean value and SD (standard deviation).…”

“…Soils having organic matter with higher humification degree are more stable and more resistant to the onset of degradation. Hence, because SOM quality is also of vital importance from the perspective of its environmental functions, as reported in several articles in the area under study (e.g., Aranda et al, 2011;Miralles et al, 2012), and coinciding with Almendros et al (2005), the interest of assessing SOM quality rather than its total concentration must be underlined.…”