Single Irrigation Can Achieve Relatively High Production and Water Use Efficiency of Siberian Wildrye Grass in the Semiarid Agropastoral Ecotone of North China

Abstract

Siberian wildrye grass (Elymus sibiricus L.) is widely planted in the agropastoral ecotone of North China (APENC). Scheduled irrigation is an important approach to increase the forage yield in this semiarid region. Based on fi eld experiments conducted in Bashang Plateau in APENC during 2002 to 2004, we studied the feasibility of applying single irrigation (SI) to increase forage yield by bringing the soil water storage in the root zone (0-60 cm) to fi eld capacity at the elongating stage. Th e results showed that Siberian wildrye grass consumed water most rapidly during the elongating stage. With 48 to 62 mm of water applied during elongating stage, forage yields reached 6000 kg ha -1 , a 110% increase compared with no irrigation (NI). With full irrigation (FI) in the growing season, forage yield was only increased by 10% compared with that under SI. Th e average water use effi ciency (WUE) under SI was 1.9 kg m -3 , a 76% increase compared with NI or a 10% increase compared with FI. Th e average irrigation water use effi ciency (IWUE) under SI was 10.8 kg m -3 which was almost three times that under FI. Th erefore, a single irrigation can be a simple agricultural practice for local farmers, and has great potential to contribute to sustainability of semiarid APENC. In addition, forage yield and WUE showed a quadratic trend with total evapotranspiration (ET). Th e maximum forage yield in this semiarid area was about 6900 kg ha -1 at 390 mm ET, whereas the maximum WUE was 1.9 kg m -3 at 360 mm ET.

Yield and Water Use Efficiency of Non‐ and Single‐Irrigated Alfalfa with Ridge and Furrow Planting in Northern China

“…Its water requirements vary from 700 to 1600 mm depending on climate and length of growing period (FAO, 2002; Kuslu et al, 2010). In contrast, a common local perennial forage grass, Siberian wild rye ( Elymus sibiricus L.), only requires water from 400 to 600 mm (Liu and Chen, 2004; Wang et al, 2009). Non‐irrigated alfalfa production is limited by precipitation, which can be erratic in certain areas (Sun et al, 2008; Wang et al, 2009).…”

“…Sufficient irrigation water is not available or is costly in this region, and deficit irrigation can be used to increase yield and WUE (Kang et al, 2002; Zhang et al, 2004; Fereres and Soriano, 2007). Wang et al (2009) showed that a single irrigation at the stem elongation stage of Siberian wild rye resulted in a relatively high forage yield and WUE. However, no information was available about applying a single irrigation during alfalfa production in semiarid northern China.…”

Yield and Water Use of Siberian Wildrye with Ridge and Furrow Planting in Northern China

“…Siberian wildrye dry matter yield was affected by available soil water in the root zone, primarily in the planted (furrow) area. In general, soil water storage in the 0‐ to 60‐cm soil layer for each individual year was affected significantly by management practice ( P < 0.001) and monitoring date ( P < 0.001).Total soil water storage in the 0‐ to 60‐cm soil layer for the RFP treatments was above the critical soil water storage [CSW, wilting point (WP) + 0.4(field capacity – wilting point) for 0‐ to 60‐cm profile; Allen et al (1998); Wang et al (2009a)] and WP (soil water content at a matric potential of –1.5 MPa, from Panigrahi and Panda, 2003) for a longer period than for the FB treatment during 3 yr (Fig. 5).…”

“…The forage grass was carefully harvested by hand using a sickle at a stubble height of approximately 5 cm after each harvest. The samples were dried at 75°C for 72 h in an oven to calculate the dry forage yield (Ercoli et al, 1999; Wang et al, 2009a). Precipitation was measured using rain gauges at the experimental site.…”

“…S iberian wildrye is a perennial forage grass widely used in semiarid northern China for its good forage quality and excellent drought and cold tolerance (Mao et al, 2003; Wang et al, 2009a); however, it frequently has low yields that do not meet the demands of the livestock industry. A main reason for the low yields is that the wet period from July to August does not coincide with the critical growth period from May to June (Sun et al, 2003; Wang et al, 2006a, 2009a).…”