TY - JOUR
T1 - Effect of tree species mixing on the size structure, density, and yield of forest stands
AU - Pretzsch, Hans
AU - Schütze, Gerhard
N1 - Publisher Copyright:
© 2015, Springer-Verlag Berlin Heidelberg.
PY - 2016/1/1
Y1 - 2016/1/1
N2 - An increasing number of studies provide evidence that mixed-species stands can overyield monocultures. But it is still hardly understood, how the overyielding at the stand level emerges from the tree, canopy, and size structure. Analyses of 42 triplets with 126 mixed and mono-specific plots in middle-aged, two-species stands of Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies [L.] Karst.), Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), and European beech (Fagus sylvativa L.) in Central Europe revealed that mixed-species compared with mono-specific stands can have (1) higher tree numbers, higher right skewness and kurtosis of the size distribution, higher inequality of tree sizes, and thereby higher stocking densities and sum of crown projection areas, (2) growth–size relationships with stronger size asymmetry of growth and higher inequality of size growth, and (3) higher stand productivity coupled with higher maximum stand density, canopy space filling, and size asymmetry. These differences depend on the species assemblage. They suggest a deeper entrance of light into the canopy as well as a higher light interception and light-use efficiency as main causes of the overyielding and overdensity. We discuss implications for research and silviculture and draw conclusions for designing and managing resource-efficient production systems.
AB - An increasing number of studies provide evidence that mixed-species stands can overyield monocultures. But it is still hardly understood, how the overyielding at the stand level emerges from the tree, canopy, and size structure. Analyses of 42 triplets with 126 mixed and mono-specific plots in middle-aged, two-species stands of Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies [L.] Karst.), Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), and European beech (Fagus sylvativa L.) in Central Europe revealed that mixed-species compared with mono-specific stands can have (1) higher tree numbers, higher right skewness and kurtosis of the size distribution, higher inequality of tree sizes, and thereby higher stocking densities and sum of crown projection areas, (2) growth–size relationships with stronger size asymmetry of growth and higher inequality of size growth, and (3) higher stand productivity coupled with higher maximum stand density, canopy space filling, and size asymmetry. These differences depend on the species assemblage. They suggest a deeper entrance of light into the canopy as well as a higher light interception and light-use efficiency as main causes of the overyielding and overdensity. We discuss implications for research and silviculture and draw conclusions for designing and managing resource-efficient production systems.
KW - Complementary light use
KW - Growth elasticity
KW - Growth partitioning
KW - Size asymmetry of competition
KW - Size asymmetry of growth
KW - Size hierarchy
KW - Space filling
UR - http://www.scopus.com/inward/record.url?scp=84955187480&partnerID=8YFLogxK
U2 - 10.1007/s10342-015-0913-z
DO - 10.1007/s10342-015-0913-z
M3 - Review article
AN - SCOPUS:84955187480
SN - 1612-4669
VL - 135
SP - 1
EP - 22
JO - European Journal of Forest Research
JF - European Journal of Forest Research
IS - 1
ER -