Investigations on the correlation pattern in even-aged stands of larch .4. Relationships between neighbourhood correlations and means of different entries

For a dynamic description of spatial neighbourhood correlation patterns of stands of larch and an analysis of temporal changes and time trends of such patterns during stand development extensive: data sets from a field trial (trial no. 1) with 27 entries of Larix decidua MILL. (Larix europaea DC.), Larix kaempferi (LAMB.) CARR. (Larix leptolepis (SIEB. et Zucc.) SIEB. ex GORD.), and Larix x eurolepis HENRY have been used. Single tree measurements of this trial were availablefor 7 stages of stand development (ages: 11, 13, 18, 19, 42, 49 and 50 years). Additionally, for a static description of spatial neighbourhood correlation patterns of stands of larch extensive data sets from 9 field trials (trials nos. 2 to 10) with a varying number (8 to 23) of entries have been used which provide an analysis of the correlations between neighbours at only one point in time. These trials are slightly different in their ages (7 to II years). Single tree measurements for all 10 trials were available for the traits height and diameter at breast height (for the 2 ages 42 and 49 of trial no. 1 only diameter measurements were available). Additionally, the diameter values are transformed and analysed as individual basal areas. The correlative structure for measurements of neighbouring individuals for these trials with regular square spacings (5 m x 5 m for trial no. 1 and 1.5 m x 1.5 m for trials nos. 2 to 10) has been described by 12 different correlation coefficients. These coefficients are defined by considering quite different spatial configurations of competitive neighbourhoods. In these procedures and analyses the diagonally located neighbours of a subject tree and its missing neighbours too are explicitly considered. The question of this paper is: Are there any relationships between means and spatial neighbourhood correlations for the different entries? Relationships valid for all traits, for all trials and for all ages = stages of stand development have not been observed for this plant material. Some interesting special results were obtained - for example: 1. For the dynamic description during stand development of trial no. 1, relationships among the yields of competing neighbours are independent on the yield level. With regard to the amount of the rank correlations (positive or negative) between means and spatial neighbourhood correlations for most cases one obtains: {height} greater than or equal to (diameter) congruent to (individual basal area). 2. For the static description of the trials nos. 2 to 10 (each with only 1 measurement) the results strongly depend on the individual trial.