Impacts of reforestation approaches on runoff control in the hilly red soil region of Southern China

Abstract

Summary Vegetation structure and soil properties are not only correlated with forest management practices, but also affect soil and water loss significantly. To estimate the long-term influences of regenerating forest cover on soil and water loss from degraded land, the runoff and soil loss in the context of different forest restoration approaches, including a control plot (CL) and plantations of slash pine (Pinus elliottii), Chinese fir (Cunninghamia lanceolata), tea-oil camellia (Camellia oleifera), and natural secondary forest, were monitored in runoff plots over a 4-year period (2000)(2001)(2002)(2003) in a hilly red soil region in Southern China. Relevant ecological factors and management intensity, were also measured. The results indicated that the four forest restoration approaches decreased surface runoff by 63.0-88.1% and soil erosion by 75.5-97.1% compared to the control. Moreover, runoff and soil erosion in tea-camellia plantation (TCP) and natural secondary forest (NSF) plots were significantly lower than with other treatments. Canopy cover, litter fall, plant roots, plant life forms, soil properties, and vegetation structure are important ecological factors that determine the magnitude of soil loss. Vegetation structure and plant life forms are the main factors reducing surface runoff and the movement of sediments. Effective control of soil and water loss in NSF and TCP are closely related to multiply stratified communities and the presence of specific plant life forms (the herbaceous keystone species Dicranopteris linearis), respectively. In addition, the above mentioned factors were sensitive to forest management patterns, including improper mechanical cultivation. Management practices should attempt to minimize disturbances to these factors to control runoff and soil erosion in each forest management unit. In particular, mechanical cultivation should loosen the soil around the base of a tree only, instead of over the entire ground surface, in the early stages of forest restoration. ª

Origin of the high sensitivity of Chinese red clay soils to drought: Significance of the clay characteristics

“…The bulk densities recorded for the top horizon in soils TS, MS and LS are similar to those recorded for many topsoils of red soils under different soil managements in southern China (e.g. Zheng et al, 2008;Huang et al, 2010) but the clay content was often less than 30 % in the soils studied.…”

“…They cover 102 million ha, including ten provinces (Cao and Zhu, 1999;He et al, 2004;Wilson et al, 2004a;Zheng et al, 2008). They develop mainly in alluvial Quaternary sediments which reorganize materials resulting from continental alteration or in continental sediments from the Cretaceous or Eocene (BGMRHN, 1988;Wilson et al, 2004a and b;Hu et al, 2010;Shi et al, 2010).…”

Effects of landscape restoration on soil water storage and water use in the Loess Plateau Region, China

“…A study by Wei et al (2007) indicated that soil water was at a better state at the early stage of tree plantation but not in the late stage. Some studies also showed that soil desiccation was developed under a 28-year-old tree plantation, and however better soil moisture was often observed under the natural forest or grassland (Zheng et al, 2008). In our study, all ecosystems had a poor soil water condition during the growing seasons.…”

Linking the soil moisture distribution pattern to dynamic processes along slope transects in the Loess Plateau, China

“…Wei et al (2007) reported that soil water content was higher in the early stage of a tree plantation than in the late stage. It has also been shown that soil desiccation developed under a 28-year-old tree plantation (Zheng et al 2008). The transition zones between an old and young plantation usually have significantly higher moisture content.…”