Abstract:

Carex leucochlora is a native turf and groundcover species in Beijing area. In order to alleviate the contradiction between green-land irrigation and water resource shortage and to practice water-saving irrigation, the evapotranspiration (ET) characteristics of C. leucochlora was studied using large auto-weighing lysimeters. It was compared with three representative turf and groundcover species, Festuca arundinacea, Buchloe dactyloides and Liriope spicata. Irrigation water demand of these turfs and groundcovers was estimated. The results showed that the ET rate of C. leucochlora varied monthly, with the highest value of 3.96±0.23 mm·d^-1 in May. Its' monthly crop coefficient was 0.73±0.09~0.95±0.03. The ET rate of the turf was slightly higher than the groundcover for C. leucochlora. The ET rates of both C. leucochlora turf and groundcover were the lowest among all the turfs and groundcovers, except the ET rate of C. leucochlora turf was slightly higher than that of B. dactyloides turf. On average, ET of F. arundinacea, L. spicata, and B. dactyloides was 1.40, 1.11 and 0.98 times of that of C. leucochlora, respectively. Under the sufficient water supply condition, the irrigation water demand during the growing season arranged from low to high: C. leucochlora groundcover (110.9~136.2 mm), B. dactyloides turf (167.1 mm), C. leucochlora turf (191.7 mm), L. spicata groundcover (233.6 mm), F. arundinacea turf (352.2 mm).

Key words: Sedge, Native plants, Landscape groundcover, Water-saving irrigation, Penman-Monteith equation

摘要：

青绿苔草（Carex leucochlora）是北京地区的乡土草坪地被植物。为缓解园林灌溉和水资源紧缺之间的矛盾，实施节水灌溉，2012-2014年采用自动称重式大型蒸渗仪研究了青绿苔草草坪的蒸散特性，与北京地区代表性的草坪地被高羊茅（Festuca arundinacea）、野牛草（Buchloe dactyloides）、山麦冬（Liriope spicata）进行了对比分析，并对各种草坪地被的灌溉需水量进行估测。结果表明，青绿苔草在不同月份的蒸散速率不同，5月的蒸散速率最高为3.96±0.23 mm·d^-1，月作物系数为0.73±0.09~0.95±0.03。青绿苔草草坪的蒸散速率高于同种地被。青绿苔草草坪地被的蒸散速率明显低于高羊茅草坪，略低于山麦冬地被，略高于野牛草草坪。以平均值计算，高羊茅、山麦冬、野牛草的蒸散速率分别是青绿苔草的1.40倍、1.11倍、0.98倍。充足水分供应条件下，生长季灌溉需水量从低到高为青绿苔草地被（110.9~136.2 mm）、野牛草草坪（167.1 mm）、青绿苔草草坪（191.7 mm）、山麦冬地被（233.6 mm）、高羊茅草坪（352.2 mm）。

关键词: 苔草, 乡土植物, 园林地被, 节水灌溉, Penman-Monteith公式