Effects of land use on phosphorus loss in the hilly area of the Loess Plateau, China

Abstract

The hilly area of Loess Plateau has some of the highest soil erosion rates in the world, and serious soil erosion causes great losses of plant nutrients. As the most common land use in Loess Plateau, slope farmland contributed most of the erosion soils. This study was designed to examine the effects of land use and slope angle of farmland on phosphorus (P) loss in the hilly area of loess plateau. Farmland (FR), barrenland (BR), and four forest treantment (seabuckthorn+ poplar (SP), immature seabuckthorn (IS), mature seabuckthorn (MS), immature Chinese pine (ICP)) were the types of land use; 10, 15, 20, 25, 30 degrees were the slope angles of FR that were compared. The results showed a larger proportion of P loss occurred in erosion soil fraction of FR, ICP, ICP, and the five slope treatments of FR; in SP, IS, and MS, P loss was primarily through runoff. FR produced more P loss than SP, IS, ICP, BR, and MS.20∼30 degrees may be the slope ranges for P loss of FR; FR in this ranges would loss more P with soil erosion. SP, IS, and MS were reasonable land uses for their less runoff, soil loss, and P loss. Farmlands over 15 degrees should be abandoned or reforested for it would produce more runoff, soil loss, and P loss.

The relative efficiency of four representative cropland conversions in reducing water erosion: evidence from long‐term plots in the Loess hilly area, China

“…Having a significant role in the course of soil-conservation schemes and land reclamation (Li, 1999;Meng et al, 2002), 60 000 hm 2 have been planted annually since 1985 (Guo et al, 2003), resulting in the present coverage of more than 200 000 hectares (500 000 acres) in the Loess Plateau. Saplings of sea buckthorn were planted in 1Á0 m by 1Á0 m spacing in March, 1986.…”

Effects of surficial condition and rainfall intensity on runoff in a loess hilly area, China

“…), crown width and ground diameter of seabuckthorn can reach 2.2 m, 2.8 cm, 1.8 m and 4.0 cm, respectively (Unpublished data). Due to this reason, total rainwater captured by canopy interception and stemflow may help to reduce raindrop energy and total runoff depth (Meng et al, 2008;Návar, 2011;Yang et al, 2013). The Hortonian mechanism (rainfall excess infiltration) under such shrub species can be greatly weakened (Wei and Sun, 2009).…”

Parsimoniously modelling perennial vegetation suitability and identifying priority areas to support China's re-vegetation program in the Loess Plateau: Matching model complexity to data availability

“…The priority areas are usually located at a 'break-of-slope' where the landform is dominated by hills and gullies and tend to be placed between highly erodible slopes and river channels. In general, revegetating these areas first would have a positive impact by intercepting the soil, nutrients Meng et al, 2008) and water coming from upslope (Liu et al, 2005). The combined effect of re-planting the priority zones only (compared to revegetating the entire, larger target area) will be that the reduction in stream flow will be minimised (see below) while maximising the reduction of soil and nutrients entering the river network.…”