Plantation forest species were introduced into South Africa due to limited availability of native forests for wood-derived products. Currently, the Mexican pine species, Pinus patula, is the most widely planted softwood species in the country. To study the effect of growth environment on wood and processing properties for the species, sample plots were established in a 20-year rotation covering a wide range of soil geologies and altitudes in Mpumalanga, South Africa. Temperature and seasonal rainfall were also determined for the sample plots. Randomly selected sample trees were harvested from the plots and processed at a plywood plant to determine veneer recovery and quality. Trees grown on sites composed of granite soils, with higher annual maximum temperatures and less rainfall, found in the Highveld region, displayed superior tree size, slenderness, and volume growth, compared to trees grown on dolomite and shale soils common to the Lowveld region. Veneer derived from Lowveld trees had more splits which were largely related to defects. Larger trees also had a greater percentage volumetric heartwood and a smaller live crown, compared to smaller trees. Highveld trees had greater net veneer recovery and produced better quality veneer than trees grown on the Lowveld. In the Mpumalanga forestry region, strong co-relatedness exists between soil geology, altitude, and climate. Although tree form and wood properties were found to differ with varying soil geology and altitude, these differences were primarily related to climate rather than soil properties. These findings highlight the pitfalls associated with neglecting either climate or soil properties when analysing site-specific growing conditions on tree growth and form.

中文翻译：

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场地质量影响人工林种植的孔雀松的树形、心材含量和单板产量

由于可生产木材产品的原生森林有限，人工林物种被引入南非。目前，墨西哥松树种，孔雀松，是该国种植最广泛的软木树种。为了研究生长环境对该物种的木材和加工特性的影响，在南非普马兰加省以 20 年轮换的方式建立了样地，覆盖了广泛的土壤地质和海拔高度。还确定了样地的温度和季节性降雨量。从地块中随机采集样本树，并在胶合板工厂进行加工，以确定单板回收率和质量。与生长在低地草原地区常见的白云石和页岩土壤上的树木相比，在高地草原地区发现的由花岗岩土壤组成的地区生长的树木，年最高气温较高，降雨量较少，表现出更优的树木尺寸、细长和体积生长。来自低地草原树木的单板有更多裂痕，这在很大程度上与缺陷有关。与较小的树木相比，较大的树木还具有较大的体积心材百分比和较小的活树冠。与低地草原上生长的树木相比，高地草原树木的净单板回收率更高，生产出的单板质量也更好。在普马兰加省林区，土壤地质、海拔和气候之间存在很强的相关性。尽管发现树形和木材特性随土壤地质和海拔的不同而不同，但这些差异主要与气候而不是土壤特性有关。这些发现凸显了在分析树木生长和形态的特定地点生长条件时忽视气候或土壤特性的陷阱。与较小的树木相比，较大的树木还具有较大的体积心材百分比和较小的活树冠。与低地草原上生长的树木相比，高地草原树木的净单板回收率更高，生产出的单板质量也更好。在普马兰加省林区，土壤地质、海拔和气候之间存在很强的相关性。尽管发现树形和木材特性随土壤地质和海拔的不同而不同，但这些差异主要与气候而不是土壤特性有关。这些发现凸显了在分析树木生长和形态的特定地点生长条件时忽视气候或土壤特性的陷阱。与较小的树木相比，较大的树木还具有较大的体积心材百分比和较小的活树冠。与低地草原上生长的树木相比，高地草原树木的净单板回收率更高，生产出的单板质量也更好。在普马兰加省林区，土壤地质、海拔和气候之间存在很强的相关性。尽管发现树形和木材特性随土壤地质和海拔的不同而不同，但这些差异主要与气候而不是土壤特性有关。这些发现凸显了在分析树木生长和形态的特定地点生长条件时忽视气候或土壤特性的陷阱。在普马兰加省林区，土壤地质、海拔和气候之间存在很强的相关性。尽管发现树形和木材特性随土壤地质和海拔的不同而不同，但这些差异主要与气候而不是土壤特性有关。这些发现凸显了在分析树木生长和形态的特定地点生长条件时忽视气候或土壤特性的陷阱。在普马兰加省林区，土壤地质、海拔和气候之间存在很强的相关性。尽管发现树形和木材特性随土壤地质和海拔的不同而不同，但这些差异主要与气候而不是土壤特性有关。这些发现凸显了在分析树木生长和形态的特定地点生长条件时忽视气候或土壤特性的陷阱。