TY - JOUR

T1 - Light transmissivity of tree shelters interacts with site environment and species ecophysiology to determine outplanting performance in Mediterranean climates

AU - Oliet, Juan A.

AU - Puertolas, Jaime

AU - Valenzuela, Patricio

AU - Vazquez de Castro, Alberto

PY - 2021/7/19

Y1 - 2021/7/19

N2 - Plastic tree shelters are commonly used in plantations under Mediterranean climates to protect against herbivory and enhance outplanting performance. However, effects on outplanting performance cannot be generalized due to the complexity of plant responses to microenvironmental conditions within the tube wall. The interactions between the light transmissivity of the tubes and species-specific responses to light and site environment on two-year outplanting performance were studied in two species with contrasting shade tolerance planted inside tree shelters with four different light transmissivities and a non-tree shelter control at two Mediterranean sites with contrasting rainfall and temperature. In general, increasing light transmissivity enhanced biomass accumulation, suggesting that the use of clear tubes might be advisable. However, the shade-tolerant Q. ilex did not benefit from the greater light transmissivity in the most arid site, indicating that the positive effect of clear tubes depends on water stress experienced by seedlings, which ultimately is determined by drought resistance strategies and site conditions. The growth of both species and survival of P. halepensis were higher within clear tubes in the continental site than in unsheltered plants, which suggests that factors other than light, such as warmer daytime temperatures or the prevention of dust deposition, can explain this beneficial site-dependent effect of tree shelters. In conclusion, our results confirm the hypothesis that the effect of tree shelter and its light transmission on outplanting performance is site and species-specific, but further research is needed to identify the effect of other effects not related to light transmission.

AB - Plastic tree shelters are commonly used in plantations under Mediterranean climates to protect against herbivory and enhance outplanting performance. However, effects on outplanting performance cannot be generalized due to the complexity of plant responses to microenvironmental conditions within the tube wall. The interactions between the light transmissivity of the tubes and species-specific responses to light and site environment on two-year outplanting performance were studied in two species with contrasting shade tolerance planted inside tree shelters with four different light transmissivities and a non-tree shelter control at two Mediterranean sites with contrasting rainfall and temperature. In general, increasing light transmissivity enhanced biomass accumulation, suggesting that the use of clear tubes might be advisable. However, the shade-tolerant Q. ilex did not benefit from the greater light transmissivity in the most arid site, indicating that the positive effect of clear tubes depends on water stress experienced by seedlings, which ultimately is determined by drought resistance strategies and site conditions. The growth of both species and survival of P. halepensis were higher within clear tubes in the continental site than in unsheltered plants, which suggests that factors other than light, such as warmer daytime temperatures or the prevention of dust deposition, can explain this beneficial site-dependent effect of tree shelters. In conclusion, our results confirm the hypothesis that the effect of tree shelter and its light transmission on outplanting performance is site and species-specific, but further research is needed to identify the effect of other effects not related to light transmission.

KW - forest restoration

KW - forestation

KW - Mediterranean climate

KW - tree shelters

KW - transplanting performance

KW - Pinus halepensis

KW - Quercus ilex

KW - water potential

KW - root growth

U2 - 10.3390/land10070753

DO - 10.3390/land10070753

M3 - Journal article

VL - 10

JO - Land

JF - Land

IS - 7

M1 - 753

ER -