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61.
Rojas-Arévalo Nadia Ovalle Juan F. Oliet Juan A. Piper Frida I. Valenzuela Patricio Ginocchio Rosanna Arellano Eduardo C. 《New Forests》2022,53(3):555-569
New Forests - The effect of shelter tubes on plant performance has been widely studied. Although, the role of shelter tubes in alleviating the effects of drought and high-irradiance stresses during... 相似文献
62.
The effects of stand stem density (SSD), orientation and distance with respect to shelter trees, and fertilisation on planted
Pinus sylvestris and Picea abies seedlings were examined at two sites, one with a southerly aspect (64°14′N, 19°46′E, 225 m
a.s.l.) and one with a northerly aspect (64°09′N, 19°36′E, 274 m a.s.l.) in boreal forests in Sweden. The damage and growth
were compared at these sites in stands with three SSD’s and different light regimes: uncut forest (SSD 500, ~500 stems/ha),
shelterwood (SSD 150,~150 stems/ha), and clear-cut (SSD, 0 stems). Half of the seedlings were irrigated with fertiliser (10 mM N).
Fertilisation and SSD affected the height growth of P. abies, since fertilised seedlings in SSD 0 grew the most (22.2 cm).
Fertilised seedlings in SSD 0 also generally had the greatest biomass (twigs, leading shoot and needles), even P. sylvestris
seedlings on the North slope, where fertilised and unfertilised pine seedlings in SSD 0 had 62.6 and 39.7 g biomass, respectively.
P. sylvestris increased about 150% in dry mass of leading shoot of the increase of P. abies with equal height growth, when
comparing SSD 150 and SSD 0. The results indicate that the general conditions of the stand have stronger effects on the growth
of planted seedlings than their orientation and distance with respect to the nearest tree and that light requirements cannot
be moderated by fertilisation. We postulate that a system in which forest gaps are formed under a shelterwood could provide
a way to regenerate forests that exploits the beneficial features of both shelter trees and clear-cuts. 相似文献
63.
Frida I. Piper 《Annals of Forest Science》2011,68(2):415-424