Prescribed burning of Pinus oocarpa in Honduras II. Effects on nutrient cycling

• Published in: Forest ecology and management 1983, Vol.5 (4), p.283-300
• Main Authors: Hudson, John, Kellman, Martin, Sanmugadas, Kandiah, Alvarado, Cesar
• Format: Article
• Language: English
• Subjects: Pinus oocarpa
• ISSN: 0378-1127; 1872-7042
• DOI: 10.1016/0378-1127(83)90033-6

The effects of prescribed burning on nutrient cycling were studied in a stand of oocarpa pine ( Pinus oocarpa Schiede) in central Honduras. Small paired runoff plots were subjected to a low-intensity prescribed burn in one of two seasons and nutrient losses in runoff water and sediment were monitored together with nutrient inputs in bulk precipitation. Burning increased the loss of nutrients and net losses of calcium, potassium and magnesium were recorded during the first 16 1 2 months after burning. Increased rates of sediment loss rather than increased losses in surface runoff were responsible for the greater part of the increase in total nutrient losses from the burned plots. Greater quantities of nutrients were lost from the plots burned just prior to the dry season than from those burned after the start of the wet season because of slow recovery of the ground vegetation during the dry season and exposure to the intense rains of May and early June. Recovery from burning was rapid and runoff and sediment loss from the burned plots approached the levels of controls 2 years after burning. As nutrient losses are a reflection of total runoff and sediment losses, it is probable that no net nutrient losses would have been detected during the 2nd year after burning had sampling been continued. The net nutrient losses recorded were small and this is attributed to the low initial fuel loadings, low fire intensities and the rapid rate of recovery of the ground vegetation. The significance of other potential sources of losses and gains of nutrients is discussed and it is concluded that low-intensity prescribed burning for hazard reduction, with burning cycles ranging from three to seven or more years, will reduce the rate of nutrient accumulation on the site rather than deplete the nutrient capital.