we examined
the effects of four canopy and three cultural treatments on plant resources and quantified relationships
between plant resources and longleaf pine seedling survival and growth. Canopy treatments
consisted of four levels of timber harvest applied to loblolly pine stands: Control (uncut, mean basal area
of 16.2 m2/ha), MedBA (single-tree selection to a mean residual basal area of 9.0 m2/ha), LowBA (singletree
selection to a mean residual basal area of 6.4 m2/ha), and Clearcut (complete canopy removal).
Within each canopy treatment, we applied three cultural treatments designed to benefit the early growth
of planted seedlings: no treatment (NT), herbicide (H), and herbicide plus fertilization (H + F). Gap light
index (GLI) significantly differed among canopy treatments and nonlinearly increased with decreasing
basal area. The H treatment resulted in higher temperatures at 10 cm in the soil. Canopy thinning
increased foliar calcium (Ca) concentration. The annual root collar diameter (RCD) increment of planted
longleaf pine seedlings was positively correlated with GLI, and foliar phosphorus (P) and Ca concentrations
but was negatively correlated with soil moisture. Our results confirm that light is an important factor
controlling the growth of longleaf pine seedlings.
we examinedthe effects of four canopy and three cultural treatments on plant resources and quantified relationshipsbetween plant resources and longleaf pine seedling survival and growth. Canopy treatmentsconsisted of four levels of timber harvest applied to loblolly pine stands: Control (uncut, mean basal areaof 16.2 m2/ha), MedBA (single-tree selection to a mean residual basal area of 9.0 m2/ha), LowBA (singletreeselection to a mean residual basal area of 6.4 m2/ha), and Clearcut (complete canopy removal).Within each canopy treatment, we applied three cultural treatments designed to benefit the early growthof planted seedlings: no treatment (NT), herbicide (H), and herbicide plus fertilization (H + F). Gap lightindex (GLI) significantly differed among canopy treatments and nonlinearly increased with decreasingbasal area. The H treatment resulted in higher temperatures at 10 cm in the soil. Canopy thinningincreased foliar calcium (Ca) concentration. The annual root collar diameter (RCD) increment of plantedlongleaf pine seedlings was positively correlated with GLI, and foliar phosphorus (P) and Ca concentrationsbut was negatively correlated with soil moisture. Our results confirm that light is an important factorcontrolling the growth of longleaf pine seedlings.
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