Effect of Groundcovers on Reducing Soil Erosion and Non-Point Source Pollution in Citrus Orchards on Red Soil Under Frequent Heavy Rainfall

Abstract

Periods of consecutive days with heavy rain of high intensity are common in the red soil region of China, increasing unpredictable risks of soil erosion and non-point source pollution on sloping orchards. Grass cover, as a type of vegetation management, is useful for controlling soil erosion and pollution. However, the potential of different kinds of groundcover plants in combating soil erosion and non-point source pollution remains unclear under the rainfall conditions in this region of China. This study included 7 d of simulated rainfall applied to a set of six treatments: Bare soil control, natural grass, and four groundcover treatments, Trifolium repens, T. repens, and Lolium perenne, Vicia sativa and Festuca elata, Medicago polymorpha, and Cynodon dactylon. The effects of the treatments on runoff volume, and soil, nitrogen, and phosphorus losses were evaluated. The results indicated that greater soil erosion and non-point source pollution occurred over the first 3d of daily 1-h simulated rainfall events. Also, the beneficial effects of the groundcover plants were greater earlier in the 7-d period of daily heavy rain, particularly in reducing runoff and nitrogen loss on the second and third day. Compared with bare soil, all the groundcovers showed a reduction effect in varying degrees, among which T. repens treatment was more effective. T. repens treatment showed an overall reduction in runoff and soil loss by 25.5% and 91.5%, respectively, and total nitrogen, nitrate nitrogen, ammonia nitrogen and total phosphorus loss by 25.5%, 74.6%, 90.7%, and 81.8%, respectively. These findings indicated that single planting of perennial pasture T. repens with short stems is an effective management option to limit soil erosion and non-point source pollution in sloping citrus orchards of southern China.

Tillage Versus No-Tillage. Soil Properties and Hydrology in an Organic Persimmon Farm in Eastern Iberian Peninsula

“…Other authors found tillage as the management with the highest soil losses and the alternative managements with the lowest ones [57]. Those results use to be relevant for groves, where the research need more surveys, for example, in the investigations conducted by Zhang et al, [35] in citrus plantation under heavy rainfall, as they found that in the comparison between Tillage and No-tillage resulted in a reduction in 26% in the runoff and 92% in the soil losses. Moreover, in vineyards was found a positive impact of the Tillage.…”

“…For instance, López-Garrido et al, [25] tested reduced tillage, Khan et al, [26] used mulches, Gilley and Risse [27] used manure, Bazzoffi et al [28] urban compost, Faucette et al [29] mulch blankets, Mtambanengwu et al [30] weeds, Smets and Poesen [31] geotextiles, Chaowen et al [32] hedgerows, and Pan and Ma [33] grasses as a cover crop. Furthermore, it is widely accepted that soil erosion is a complex process that is difficult to understand and manage, but also it is accepted that there are already possible solutions [34], and those solutions can be applied in the agriculture [35] and forest lands [36]. For example, No-Tillage is an option to reduce soil erosion rates.…”

Response Model for Urban Area Source Pollution and Water Environmental Quality in a River Network Region

“…Area source water pollution occurs in a multifaceted manner and is involved in several dynamic processes, including rainfall runoff, soil erosion, pollutant accumulation, and leaching of soil solutes. Area source pollution is random, complex, uncertain, and characterized by hysteresis [ 3 , 4 , 5 ]. With rapid urbanization, the proportion of impervious surfaces in downtown areas has increased.…”

Effects of Tillage Methods and Vegetation Coverage on Reducing Runoff and Soil Erosion

“…There is often a heavy rainfall precipitation and intensity here. As a result, RSHR is one of the most serious soil erosion areas in China [1][2][3][4]. Soil erosion has seriously affected the sustainable development of agriculture and economy in the entire region [5,6].…”

“…The amount of runoff and soil erosion depend on rainfall precipitation and intensity. At the same time, tillage methods and vegetation coverage type have an important impact [1,3]. Using the simulated rainfall methods, Wang et al studied the runoff and soil loss characteristics of 8 common land-use types under different rainfall conditions.…”