Quantified Benefits of Cultivating Day-Lily (Hemerocallis citrina) Hedgerows over Multiple Years on Sloped Red-Soil Farmland, Southern China

Abstract

Planting hedgerows is an effective measure for increasing soil and water conservation on sloped farmland, although the comprehensive and dynamic changes in benefits across the life span of the hedgerow are not fully understood. To expand our understanding in this area, day-lily (Hemerocallis citrina) was selected to research the effect of hedgerows built on sloped red-soil farmland in southern China. In situ observations of runoff and soil loss from 2012 to 2018 were recorded in triplicate for two treatments: (1) conventional downslope-ridge tillage (CT) and (2) hedgerow intercropping with downslope-ridge tillage (HT). Micro-topography, soil nutrient content, and crop yield changes in the study plots were recorded. Hedgerows began intercepting runoff and soil loss simultaneously from the second year after they were planted, reducing annual surface runoff (35-66%) and annual erosive sediment (32-87%). As hedgerows became established, they provided increasing positive effects on soil and water conservation. However, those beneficial effects were gradually obscured by changes in micro-topography. The presence of the hedgerow had no obvious influence on soil total nutrient contents under this experimental condition. On average, planting the hedgerow reduced peanut yield by 21% but reduced rapeseed yield only by 2%. Compared with CT treatment, the average economic output of HT treatment after reaching the hedge's initial production was 1.52 times greater, showing a quadratic trend and reaching a maximum about 4 years after construction by regression. These findings indicate that hedgerow management could be optimized according to the desired beneficial soil and water conservation or crop yield characteristics in different developmental phases.

Effects of Different Hedgerow Patterns on the Soil Physicochemical Properties, Erodibility, and Fractal Characteristics of Slope Farmland in the Miyun Reservoir Area

“…Our results were consistent with these earlier mentioned studies, and we observed that all four hedgerow patterns can increase the soil nutrient content to different degrees, which, however, differs from the results of Zheng. They carried out a hedgerow-crop intercropping experiment during 2012–2018 and discovered that the TN, TP, and SOM contents recorded in the hedgerow plots showed unclear variation trends relative to the control plot, by being slightly high or low at one time or another, thereby having little effect on the total nutrient content in the topsoil [ 14 ]. This was mainly due to the differences in environment, cultivation management, and hedge species and the lack of competition of crops for soil nutrients in this experiment.…”

“…Hedgerows have been widely used on slope farmlands in China and abroad in social production due to their water and soil conservation effects, such as soil erosion reduction and non-point-source pollution control [ 14 , 15 , 16 , 17 ]. Overground and underground hedgerows contribute to 62.25 and 37.75% of runoff reduction along with 60.44 and 39.56% of the sediment reduction advantages on average, respectively [ 18 ].…”

Erosion of Granite Red Soil Slope and Processes of Subsurface Flow Generation, Prediction, and Simulation

“…The red soil hilly region of southern China is an important agricultural production area [17], accounting for 36% of the total cultivated land and more than 50% of the total output of oil-bearing crops, grain, and agricultural in China [18]. The red soil sloping farmland developed from the weathered granite parent materials is widely distributed here and is the primary source of soil erosion [19,20], and the soil loss rate can reach 98.78 t ha −1 yr −1 . There is a large total amount of rainfall in this area but with extremely uneven distribution of temporality and spatiality.…”

Response of Herbaceous Vegetation Communities in Terraces of Ecological Isolation Zones in the Mountain Red Soil Area

“…At present, many scholars from both China and overseas have done a lot of scientific research on the ecological isolation zone, mainly focusing on the anti-erosion performance of the soil [7][8][9][10], the nutrient change of the ground [11][12][13][14], the soil microbial community [11,15,16], the stability of the soil aggregate structure [17][18][19] and the interception of pollutants [8,[20][21][22][23] after the ecological isolation zone. In contrast, there are fewer studies on the response of herbaceous vegetation communities and soils in terraces of ecological isolation zones in the mountain red soil area, and there are no studies and evaluations on the maintenance and monitoring of ecological isolation zones after their installation.…”