Previous land use alters plant allocation and growth in forest herbs

Abstract

Summary1 Former human practices can persistently influence forest ecosystems, particularly by altering the distribution and abundance of vegetation. Previous research has focused on the role of colonization success in governing plant community patterns in abandoned forests, but few studies have explored how changes in the performance of adult plants may contribute to changes in plant populations. 2 We examined patterns of biomass allocation and growth of 12 herbaceous plant species in southern Appalachian forest stands that have developed after agricultural abandonment or logging at least 55 years ago, to determine whether plant performance varied with land-use history. Soil nutrient availability and canopy closure were also investigated. 3 Adult plant biomass allocation varied appreciably among stands with different histories. Herbs in farmed stands generally allocated the most to leaves and the least to stems, while reference stands showed the opposite pattern. Plants in previously farmed sites had the highest rate of growth, although we observed considerable interspecific variation in plant performance. Stem allocation and relative growth rate were positively correlated in reference stands, but not in farmed or logged stands. Similarly, the growth of plants was clearly associated with soil nutrient concentration in reference stands but not in farmed or logged stands. 4 Differences in understorey density and soil nutrient availability may account for the observed patterns. Total herbaceous cover was appreciably lower in farmed and logged stands (58% and 51%) than in reference stands (78%), and soil phosphorus was higher in farmed stands than in logged and reference stands. Thus, competition for light and nutrients may be lower in farmed and logged stands than in reference stands, despite there being no difference in canopy closure with land-use history. 5 Overall, these results suggest that land-use history may influence environmental variables in ways that can enhance the performance of some herbaceous species. However, not all species may respond similarly to these changes.

Community Composition and Tree Population Structure in Undisturbed and Disturbed Tropical Semi-Evergreen Forest Stands of North-East India

“…Number of shrub species was higher in the undisturbed stand (18) than in the disturbed stand (16). Nonetheless, the number of herbaceous species remained higher in the disturbed stand (30) than in the undisturbed stand (17). Castanopsis tribuloides was common in both stands, and showed dominance in the undisturbed stand with a density of 90 individuals' ha -1 .…”

“…[62] found that space created by small canopy gaps and environmental historical factors were of comparable importance for controlling herb species composition and distribution while space was of somewhat greater importance for woody plants, and that the past human land use hand a strong impact on species composition on the Barro Colorado Island of Panama. [17] also described that the allocation and growth of herbaceous plants can be altered by previous land use, in their experiment with 12 herbaceous plant species in southern Appalachian forest stands of USA. Thus, the higher total species diversity and lower tree species composition in the disturbed stand may be attributed to the stand characteristic allowing the light-demanding herbaceous species to increase, and in turn suppressing the tree seedlings due to competition with the herbaceous species.…”

Dissolved soil organic carbon and nitrogen were affected by conversion of native forests to plantations in subtropical China

“…A change in land-use management practices including the conversion from native forests to plantations can alter the rate and type of litter input because of changes in species composition and plant growth rates (Fraterrigo et al 2006;Jandl et al 2007), and subsequently WSOC concentrations (Fig. 3).…”

Plasticity in response to phosphorus and light availability in four forest herbs

“…Baeten et al 2009). The number of studies that explore how the (a)biotic legacies of former agricultural practices influence the establishment, performance and persistence of forest herbs is gradually increasing (e.g., Verheyen and Hermy 2004;Vellend 2005;Fraterrigo et al 2006;Flinn 2007;Baeten et al 2009). …”