Nutrient relocation, hydrological functions, and soil chemistry in plantations as compared to natural forests in central Yunnan, China

Abstract

Nutrient relocation, hydrological functions, and soil chemistry in plantations as compared to natural forests in central Yunnan, China Abstract The relocation of nutrients among dominant plant species, along with hydrological functions and soil chemistry in five plant communities, including Eucalyptus plantation, Pinus plantation, shrubland, semi-natural, and natural secondary forests were investigated in central Yunnan, China. The nutrient P, N, and K accumulation in above-ground biomass of Eucalyptus smithii (stems, barks, branches, and leaves) were the highest, followed by Pinus yunnanensis of both the Pinus plantation and the semi-natural forest. The nutrient retranslocation efficiency (NRE) of E. smithii was the highest for nutrient P, N, and K with values of 56, 66, and 67%, respectively, among the dominant plant species of the five plant communities, while the NRE of P. yunnanensis in Pinus plantation had the second highest value of NRE for nutrient N. The nutrient content (available P, N, and soil organic matter) in the upper two soil layers under Eucalyptus and Pinus plantations was correspondingly found to be lower than that of the other forests. Moreover, under the Eucalyptus and Pinus plantations, surface runoff, soil erosion, and nutrient loss were more serious, and the water storage of litterfall and canopy interception were significantly lower than that in the other plant communities. Accordingly, we suggest that single-species plantations cannot present the same ecological benefits as natural forests, because of their simple, uniform structures, and the characteristics of the dominant plant species.

Leaf nitrogen and phosphorus stoichiometry of plant communities in geochemically phosphorus-enriched soils in a subtropical mountainous region, SW China

“…Our results showed that soil N in the GPES region was not high (total N: 0.78 9 10 3 mg/kg; available N: 87.4 mg/ kg), similar to results obtained by Hou et al (2010) from non-GPES in Central Yunnan. It is hard to identify nutrient limitation from the mean soil N contents (Han et al 2011); the mean L N:P found in GPES was just 4.96; therefore, according to the eco-stoichiometry theory, N was limited at our study site (Güsewell 2004).…”

“…Our results showed that soil in the GPES region had extremely high total P (6.57 9 10 3 mg/kg) and available P content (381.54 mg/ kg), which were significantly higher than the results obtained by Hou et al (2010) from non-GPES regions in Central Yunnan. The soil P level in GPES in Central Yunnan was significantly higher than the P-enriched threshold identified by Delorme et al (2000), where GPES had higher soil P content and variability, and was very different from other P-enriched regions identified in earlier studies, e.g., pasture and farmland (Delorme et al 2000;Read 2012;Sharma and Sahi 2005).…”

“…By comparing the reference data and previous results from Central Yunnan (Hou et al 2010) with results obtained in this study, it was determined that geochemical features of GPES were the most important drivers of leaf N and P stoichiometry at this site, rather than other factors such as longitude and latitude, climate, and plant type.…”

The Subtropical Vegetation of Southwestern China

“…Song ( 2013 ) asserted that the subtropical evergreen broad-leaved forest of China corresponds to the region from 23° to 33° N and from 98° to 123° E. In fact, within Yunnan the forest extends west to c. 97°32′ E (e.g. SW China, especially Yunnan, is home to the most diversifi ed subtropical EBLFs to be found in East Asia (Tang and Ohsawa 2009 ;Tang 2010 ;Tang et al 2013 ). Chayu and Motuo in Yaluzangbujiang, though in deep gorges at 100-600 m asl, very limited patches of the tropical rain forest dominated by Dipterocarpus are found).…”

“…The most important factors in the loss of plant diversity are habitat fragmentation and degradation in the subtropical areas of SW China (Tang 2010 ). In Yunnan Province, 90 plant species were recorded in the national priority protection list/ inventory (Li et al 2003 ).…”