In many second-rotation Pinus radiata forest planta-tions, there has been a steady trend towards wider tree spacing and an increased rate of application of P fertiliser. Under these regimes, the potential for understo...In many second-rotation Pinus radiata forest planta-tions, there has been a steady trend towards wider tree spacing and an increased rate of application of P fertiliser. Under these regimes, the potential for understory growth is expected to in-crease through increased light and greater nutrient resources. Therefore, understory vegetation could become a more signifi-cant component of P cycling in P. radiata forests than under closely-spaced stands. Studies have shown that growth rates and survival of trees is reduced in the presence of understory vegeta-tion due to the competition of understory vegetation with trees. Other studies have suggested that understory vegetation might have beneficial effects on nutrient cycling and conservation within forest stands. This review discusses the significance of understory vegetation in radiata pine forest stands, especially their role in enhancing or reducing P availability to forest trees.展开更多
Silvicultural approaches at forest plantations with wider initial tree spacing have created potential for increased understory vegetation growth in response to increased light and greater nutrient resources. In conse-...Silvicultural approaches at forest plantations with wider initial tree spacing have created potential for increased understory vegetation growth in response to increased light and greater nutrient resources. In conse- quence understory vegetation can fill a more important role in forest ecosystems, especially in interactions （competi- tion or facilitation） between understorey vegetation and forests trees that might affect tree growth and nutrition. Considerable research has been carried out on plant inter- ference. However, the experimental designs used in these studies vary from one study to another, and from species to species depending on the aims, objectives and practicalities of the studies. Thus there is no optimum design for com- petition experiments. This review discusses designs avail- able in studying plant interferences in a glasshouse, particularly the effects of below-ground interaction of understorey vegetation and forest trees.展开更多
文摘In many second-rotation Pinus radiata forest planta-tions, there has been a steady trend towards wider tree spacing and an increased rate of application of P fertiliser. Under these regimes, the potential for understory growth is expected to in-crease through increased light and greater nutrient resources. Therefore, understory vegetation could become a more signifi-cant component of P cycling in P. radiata forests than under closely-spaced stands. Studies have shown that growth rates and survival of trees is reduced in the presence of understory vegeta-tion due to the competition of understory vegetation with trees. Other studies have suggested that understory vegetation might have beneficial effects on nutrient cycling and conservation within forest stands. This review discusses the significance of understory vegetation in radiata pine forest stands, especially their role in enhancing or reducing P availability to forest trees.
基金financially supported by Massey University and the Centre for Sustainable Forest Management at Forest Research Institute,New Zealand
文摘Silvicultural approaches at forest plantations with wider initial tree spacing have created potential for increased understory vegetation growth in response to increased light and greater nutrient resources. In conse- quence understory vegetation can fill a more important role in forest ecosystems, especially in interactions （competi- tion or facilitation） between understorey vegetation and forests trees that might affect tree growth and nutrition. Considerable research has been carried out on plant inter- ference. However, the experimental designs used in these studies vary from one study to another, and from species to species depending on the aims, objectives and practicalities of the studies. Thus there is no optimum design for com- petition experiments. This review discusses designs avail- able in studying plant interferences in a glasshouse, particularly the effects of below-ground interaction of understorey vegetation and forest trees.
