Factors explaining variability in woody above-ground biomass accumulation in restored tropical forest

Abstract

This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues.Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. Secondary forests comprise an increasing area of the tropics and play an important role in global carbon cycling. We compare above-ground biomass accumulation of both planted and naturally regenerating trees, as well as C in the top soil layer, in three restoration treatments replicated at 14, six to eight year old restoration sites in southern Costa Rica. Restoration strategies include: control (no planting), planting tree islands, and conventional, mixed-species tree plantations. We evaluate the importance of past landuse, soil nutrients, understory cover, and surrounding forest cover in explaining variation in aboveground biomass accumulation (ABA) rate across sites. Total ABA and planted tree ABA rate were highest in plantations, intermediate in islands, and lowest in control treatments, whereas ABA rate of naturally regenerating trees did not differ across treatments. Most ABA in plantations (89%) and islands (70%) was due to growth of planted trees. Soil carbon did not change significantly over the time period of the study in any treatment. The majority of across-site variation in both total and planted tree ABA rate was explained by duration of prior pasture use. Tree growth in the first two years after planting explained approximately two-thirds of the variation in ABA rate after 6-8 years. Soil nutrient concentrations explained relatively little of the variation in planted or naturally recruiting ABA rate. Our results show that planting trees substantially increases biomass accumulation during the first several years of forest recovery in former agricultural lands and that past-land use has a strong effect on the rate of biomass accumulation. Planting tree islands is a cost-effective strategy for increasing ABA and creating more heterogeneous habitat conditions than tree plantations. We recommend small scale planting trials to quickly assess potential biomass accumulation and prioritize sites for ecosystem service payments for carbon sequestration.

Determinants of Aboveground Biomass across an Afromontane Landscape Mosaic in Kenya

“…Plantation of trees on former agriculture lands substantially increases biomass accumulation during the first few years of forest recovery in the restored tropical forest in Costa Rica [74]. In addition to the small and fragmented indigenous forest patches, the Taita Hills host plantations of exotic tree species, such as Cupressus lusitanica, Eucalyptus spp., Grevillea robusta and Pinus spp.…”

Land use legacy effects on structure and composition of subtropical dry forests in St. Croix, U.S. Virgin Islands

“…aboveground biomass accumulation relative to natural succession (Lugo, 1992;Aide et al, 1995;Cusack and Montagnini, 2004;Holl and Zahawi, 2014), particularly since plantation species are often selected for rapid growth. Biomass accumulation in naturally regenerated secondary forests, especially those regrowing on abandoned agricultural land, tends to occur in later successional stages (Brown and Lugo, 1990;Guariguata and Ostertag, 2001;Holm et al, 2012), though rates depend on the intensity of previous land-use activities (Holl and Zahawi, 2014;Silver et al, 2000).…”

Biomass and Soil Carbon Stocks in Wet Montane Forest, Monteverde Region, Costa Rica: Assessments and Challenges for Quantifying Accumulation Rates

“…Applying this rate to the La Calandria data would suggest a forest age of only 30 years, which is inconsistent with the trunk diameters, as noted above [24]. However, various studies have noted that rates of biomass accumulation during reforestation can vary greatly depending on numerous factors, many related to previous land-use [25]. For example, a study by Uhl et al [26] found that carbon accumulation rates on reforested pasture varied by more than an order of magnitude depending on the duration and intensity of grazing.…”

“…Both accumulation rates we measured in the secondary forests are much lower than those observed in previous studies of carbon accumulation in tropical secondary forests, for example, the aforementioned rate of 4.9 tC ha −1 yr −1 measured in Peruvian cloud forests [23], a rate of 5.5 tC ha −1 measured in the Amazonian Basin [27], or the hypothetical rate suggested above for the MVI mature forest of 2.75 tC ha −1 . We speculate, therefore, that reforestation on these plots is limited by some factor, such as nutrient availability, resulting from prior landuse [25], or nutrient limitation of the rhyolitic material.…”