Short-Term Effects of Pile Burn on N Dynamic and N Loss in Mediterranean Croatia

Abstract

There is a lack of information in the rural Mediterranean area about agricultural pile burning impacts on soil nitrogen (N) dynamic and the N loss. Therefore, this research aims to study the impacts of moderate (MS), and high (HS) severity burn on N transformation and N losses, compared to an unburned (C) during the first year. The experimental plots (10 m2) were established in Croatia (43°58′ N 15°31′ E), in a slope ~18°, with a southwest exposition. Five days after the burn, C treatment had a significantly higher total N (TN) than MS and HS. Generally, the runoff was significantly different between burned and C treatments. Sediment yield, concentrations, and TN loss were significantly higher in MS than in C treatment. The concentrations of ammonium (NH4-N) and nitrate (NO3-N) in the runoff, and their losses were higher in burn treatments than in C treatment. These values were high in the first three months after burn, although the peaks in later periods correspond to extreme rainfall events. Principal component analysis showed that sediment yield was associated with sediment concentration, runoff, and TN loss (Factor 1). In addition, rainfall amount and intensity were inversely related to NH4-N concentration and losses (Factor 2). The NO3-N concentration was positively related to NO3-N losses. Overall, MS treatment had severe effects on N loss and, sediment yield can be used as an indicator of soil degradation after pile burns.

Recovery of herb‐layer vegetation and soil properties after pile burning in a Midwestern oak woodland

“…In addition, our burn scars were located in a riparian zone where sediments and organic matter can be deposited during minor flooding events or from upslope erosion. These processes can also be accelerated by site‐level burning (Santín & Doerr 2016; Delač et al 2020), which occurred twice during our study. Fourth, previous studies have predominately occurred in conifer‐dominated ecosystems where rates of passive vegetation recovery may differ relative to Midwestern oak woodlands, due to differences in vegetation, soils, climate, and management practices.…”

Effect of Rice Straw and Stubble Burning on Soil Physicochemical Properties and Bacterial Communities in Central Thailand

“…Ammonium (NH 4 -N) and nitrate (NO 3 -N) are the plant-available forms of nitrogen, and are generated via the decomposition of organic N compounds [ 39 ]. Previous studies [ 40 , 41 , 42 ] have reported high NH 4 -N concentrations after high-severity burning, whereas NO 3 -N did not form directly through heating [ 43 ], but was produced after burning through the nitrification of NH 4 -N [ 44 ]. This might explain the significant decrease in NO 3 -N of the paddy soils after burning ( Table 2 ).…”

Extremes Rainfall Events on Riparian Flora and Vegetation in the Mediterranean Basin: A Challenging but Completely Unexplored Theme

“…Despite the increase in magnitude and frequency of phenomena such as fires and floods as a result of global change, only a few articles (six and four respectively) have analyzed the impact of these phenomena on vegetation. In the articles related to the fire topic, the main environmental factors that determine severity affecting forest formations located in Mediterranean Basin have been identified and evaluated [146][147][148][149][150]. The studies relating to flood effects on vegetation dealt with flooding risk analysis, assessed on different vegetation types by simulations and models [121,151], by reconstructions of flash floods tree-ring based [152] and by sustainable tools to mitigate urban flood risk [123].…”