正线性相关 meaning in English

positive linear correlation

The petiole and leaf lengths and leaf widths and cork thicknesses and seed widths of the quercus variabilis communities appeared to have a second - degree parabola relation with the latitudes of the communities ; the petiole lengths and leaf lengths and cork thickness appeared to have a clear second - degree parabola relation with the elevations of the communities ; the leaf and seed lengths appeared to have a clear positive correlativity with the elevations ; the seed lengths had a typical negative correlation with the elevations
栓皮栎种群的叶柄长、叶长、叶宽、栓皮厚度、种长和种宽随纬度呈现出二次抛物线关系；叶柄长、叶长和栓皮厚度随海拔高度呈现明显的二次抛物线关系；叶宽和种宽随海拔高度的变化呈现出明显的正线性相关；种长与海拔的关系为一种典型的负线性相关。