【作者】 李焕波；

【导师】 张林森；

【作者基本信息】 西北农林科技大学 ， 果树学， 2008， 硕士

【摘要】 近年来,随着我国西部黄土高原苹果栽种面积逐年增大,西部大部分地区干旱缺水的矛盾日益加大,因此,对果园用水管理显得尤为重要。为了给该地区苹果园的适时、适位和适量节水灌溉技术提供理论基础和技术指导,需要准确了解果树蒸腾耗散过程,理解果树对水分的吸收利用机制。本文在国内外对苹果树树干茎流速率研究的基础上,于2007年4月到2007年10月在凤翔县大沙凹村陕西省宝鸡市苹果专家大院的苹果园内,研究了黄土高原地区自然栽培条件下红富士苹果树在不同条件下的树干茎流速率变化,并对此条件下影响树干茎流速率的因子进行了分析。此外,生长季在陕西省黄陵县隆坊镇马塔农场苹果园也进行调查和安装仪器测定。通过试验得出了如下结论:(1)一般树龄8～10年开始出现心材,树体的边材厚度一般在30～48 mm。就单棵树而言,边材径向液流速度的总趋势是从形成层向内逐渐减少,边材12 mm处的液流速率占5 mm处液流速率的0.6～0.7,而32 mm处的速率仅为5 mm处的0.2左右。(2)苹果园红富士树干的液流速率变化在晴天表现为单峰曲线,在生长季4-8月期间晴天,树干茎流在早晨6:30～7:00时开始启动,在形成层下5 mm处树干茎流速率在4～5 cm/h以上,在12:30～14:30时达到最大值,期间树干茎流速率基本保持在45～57 cm/h以上,最大值可达到64.6 cm/h。在22时树干茎流速率降低到最低水平,并维持到第二天液流启动时,在这段时间内树干内几乎没有树液流动。在阴天表现为较低水平的多峰曲线。(3)在苹果主要生长期内,一天内树干液流与太阳辐射变化规律相同,且太阳辐射先于树干茎流速率到达峰值。太阳辐射对树干茎流速率有直接的影响作用,并且与空气温度、空气湿度综合作用影响气孔阻力变化,进而影响树干茎流速率。其他条件相同时,土壤水分过度亏缺会导致树干茎流速率降低。更多还原

【Abstract】 The plantation area of apple trees expands increasingly recently in the west of china, while this area is short of water. In water shortage areas, it is especially important to manage water use of fruit trees effectively. Therefore, in order to guide the irrigation at right time, suitable amount and proper place and provide a theoretical basis and the technical guidance, it is important to understand transpiration process and mechanism of water uptake and use in the apple tree.In this thesis, the present status and existing problems of water transport mechanisms and sap velocity of apple were analysed firstly. From April to October in 2007, experiments were conducted in Baoji demonstration apple orchard located at Dashaao, Fengxiang, Baoji, Shanxi province to investigate the sap flow velocity change in different condition of apple trees grown in Loess Plateau with common management and analysis the effecting factor. The same experiment was conducted at Mata farm located at Huangling Shanxi province.The main results are as follow:(1) The trend of the sap flow velocity along the radius below the cambium in sapwood is decreasing to the heartwood as a single tree. The velocity of the position 12 mm under the cambium is 0.6 to 0.7 of velocity at 5 mm, while the velocity at 32 mm is only 0.2 of velocity at 5 mm.(2) The trunk sap flow velocity behaves a single-peak curve in sunny days, the sap flow velocity begins ascending at 6:30-7:00 from April to August, the velocity can be more than 4 to 5 cm/h and reaches peak at 12:30-14:30. In this period, the velocity keep more than 45 to 57 cm/h, maximum is 64.6 cm/h. the velocity get the lowest at 22:00 and keep it to the next morning. In this period, there is almost no big sap flow, the trunk sap flow velocity behaves a more-peak curve in the cloudy day, and the peak velocity is low.(3) In the main growing season of apple, the change of sap flow velocity is the same with the solar radition, and the peak of solar radiaton is get earlier than the peak of sap flow velocity. The solar radition has a direct effect on the sap flow velocity.There is a combined impact caused by solar radiation, air temperature and RH on the resistance of stoma,then effects the change of the sap flow velocity of the apple trees. In the same condition, soil moisture deficit excessively would lead the sap flow lower更多还原