Exotic Pinus carbaea causes soil quality to deteriorate on former abandoned land compared to an indigenous Podocarpus plantation in the tropical forest area of southern China

Abstract

Soil properties under an exotic plantation (Pinus caribaea) and an indigenous plantation (Podocarpus imbricatus) were compared with adjacent secondary forests and abandoned land in the tropical forest areas of Jianfengling National Nature Reserve in Hainan province, southern China. The surface soil (0-0.2 m) under Pi. caribaea has higher bulk density, lower soil organic carbon, total N, total K, available N, microbial biomass carbon, and smaller soil microbial communities (as indicated by soil Biolog profiles) than under Po. imbricatus. Both land use types showed negative cumulative soil deterioration index (DI) compared to secondary forests. However, compared to abandoned land (DI = -262), the soil quality of Po. imbricatus showed improvement (DI = -194) while that of Pi. caribaea showed deterioration (DI = -358). These results demonstrated that these exotic pine plantations can significantly and negatively influence soil properties. By contrast, our results showed that adoption of indigenous species in plantations, or natural regeneration, can improve soil quality.

Changes in soil microbial community structure and metabolic activity following conversion from native Pinus massoniana plantations to exotic Eucalyptus plantations

“…Soil microbial communities in plantations are affected by multiple factors including forest type, climate, soil condition, and management practices (Wei et al, 2009;Burton et al, 2010;Ibell et al, 2010). In this study of paired P. massoniana and Eucalyptus plantation sites, each pair had different soil and microclimate conditions, which strengthen our results and shows they may be applicable to a variety of settings.…”

“…The rapid growth rates of exotic species plantations, when compared to native forest, have shown to exhaust soil water and nutrient resources (Turnbull, 1999), alter the quantity or quality of carbon input (Rothstein et al, 2004), and prevent understory vegetative growth by direct physical disturbance (weed control or other forestry-related activities) or direct chemical interference (Zhang and Fu, 2009). Exotic plants can also disrupt ecological associations between soil microbial communities and previous native communities (Kasel et al, 2008), thus resulting in decreased biodiversity, soil erosion, and losses in fertility (Wei et al, 2009).…”

Carbon metabolism of soil microbial communities of restored forests in Southern China

“…As a result, the natural secondary forest was expected to be more responsive to environmental changes (Huang 1999) and would be more stable in coping with external stresses. Among the two artificially restored forests, plantation of native species was preferred over that of introduced species in terms of threats of ecological crises (Parrotta et al 1997;Wei et al 2009;Zhang and Chu 2010). There were larger differences in CLPPs between the natural secondary forest and the slash pine plantation than between the natural secondary forest and the Masson pine plantation.…”

“…The first was a passive restoration approach of re-establishing the natural secondary forest by not disturbing the harvested forest (Zhang and Dong 2010) and allowing the vegetation to re-establish in natural and near natural manner (Fu et al 2004;Sayer et al 2004;Stone 2009;Wei et al 2009;Zheng et al 2008). The second type of restoration was to reforest with an introduced species dependent on levels of forest and soil degradation, residual vegetation, and desirable restoration outcomes (Chazdon 2008).…”

Soil microbial community structure and function responses to successive planting of Eucalyptus

“…However, this form of landuse conversion often exhausts soil nutrients and decreases soil quality (Wei et al, 2009) because of the large demand for nutrients by fast-growing species (Laclau et al, 2010) and forestry-related activities (e.g., weed control, soil preparation, and plantation tending), which consequently influences the sustainability of plantations.…”