不同灌水强度下中国沙棘苗木生长过程

Growing Process of Hippophae rhamnoides L.subsp.sinensis Seedling under Different Irrigation Intensities

为探讨水分条件对中国沙棘动态生长及生产力的影响,通过田间灌水试验模拟不同水分梯度下的中国沙棘生长情况,以其动态生长量数据为基础材料,基于多形曲线方法并以灌水强度代替此法中的地位指数,构建中国沙棘苗高(新梢)和地径的多形灌水强度年生长模型。结果表明:(1)不同灌水强度处理间,苗高和地径的Logistics模型3参数皆体现出一定程度差异,参数K和参数b存在极显著差异(Sig.≤0.01),参数a存在显著差异(0.01<Sig.≤0.05)。(2)根据生长模型5个生物学意义在灌水处理间的多重比较可知:灌水强度主导的参数差异性使苗高、地径生长模型具备了多形性。(3)在0 6倍灌水强度内,苗高、地径生长模型参数K符合二次曲线,参数a符合幂函数,参数b符合二次曲线,并据此回归结果构建了中国沙棘苗高和地径的多形灌水强度生长模型。(4)分析多形灌水强度模型的生产力可知:灌水量为天然降水量的4.83倍时苗高年生长量最大,而地径年生长量最大所需的灌水倍数略低于苗高,为天然降水量的4.53倍。

To study the dynamic growth and productivity of Hippophae rhamnoides L.subsp.sinensis under different water conditions,an annual growth model of H.rhamnoides L.subsp.sinensis in respect of height（new shoot） and ground diameter under polymorphic irrigation intensities was established with the dynamic growth increment data collected from experiments on the growth of H.rhamnoides L.subsp.sinensis under different water conditions simulated by field irrigation,and based on the polymorphic curves method in which the site index was replaced by the irrigation intensity.The results of study showed that：（1） There were differences in three parameters of the Logistic Model regarding to the height and grand diameter under different irrigation intensities： the differences in parameter K and parameter b were extremely significant（Sig.≤0.01） while the difference in parameter a was significant（0.01Sig.≤0.05）.（2） The multiple comparisons among 5 Biological Meanings of the growth model under different irrigations revealed that： The growth model of height and ground diameter had polymorphism caused by the differences of parameters leaded by different irrigation intensities.（3） When the irrigation intensity was 06 times more than rainfall,the parameter K and b in growth model of height and ground diameter accorded with the quadratic curve respectively,parameter a accorded with the power curve.These regression results contributed to the establishment of the polymorphic irrigation intensity growth model of H.rhamnoides L.subsp.sinensis in respect of height and ground diameter.（4） The analysis on the productivity of the polymorphic irrigation intensity growth model indicated that the increment in respect of height turned to be the greatest as the irrigation intensity was 4.83 times of the normal rainfall,while in respect of ground diameter,4.53 times.