Published results on the growth interactions of non-nitrogen fixing mixed plantations species, and their impact on the regeneration of woody plants are scant. This paper addresses the growth interactions of pure and m...Published results on the growth interactions of non-nitrogen fixing mixed plantations species, and their impact on the regeneration of woody plants are scant. This paper addresses the growth interactions of pure and mixed plantations of Eucalyptus camaldulensis and Cupressus lusitanica and their impact on the regeneration of woody plants in relation with light. Data on the regenerated woody plants, individual characteristics of the plantation species and light reaching under the canopies were collected using sample plots (n = 4) with a size of 20 m × 20 m for each plantation type. The result showed that, E. camaldulensis was suppressing the growth of C. lusitanica while its growth was favored when it was mixed with C. lusitanica (p < 0.05). There were no significant differences between the pure and mixed plantations in their diversity and density of undergrowth woody plants (p > 0.05). Density of plantation trees were found not having a significant relationship with diversity of species (p = 0.801). There was a significant but not direct relationship between light reached in the understory of the canopies and diversity of species in the plantations (p = 0.027). Overall, the result indicated that both the pure and the mixed plantations were favoring the recruitment of woody plants.展开更多
A study was conducted to evaluate the status of soil nutrients under E. grandis plantation in comparison with that in its adjacent submontane rain forest. Twenty sequare plots, with an area of 20 m×20 m for each,...A study was conducted to evaluate the status of soil nutrients under E. grandis plantation in comparison with that in its adjacent submontane rain forest. Twenty sequare plots, with an area of 20 m×20 m for each, were established in both of E.grandis plantation and its adjacent sub-montane rain forest, independently. Soil samples were collected from each square plot, at five points （at the four comers and at the center） of each plot. The collected soil samples were mixed to make a composite and representative sample for each plot, independently. The analyses were done in a soil laboratory following appropriate methods. The analysis result indicated that there were no significance differences between E. grandis plantation and its adjacent sub-montane rain forest in the level of major soil nutrients （total N, available P, exchangeable K, Ca and Mg）, pH and total carbon of soils （p 〈 0.05）. There were significance differences between two sites of forest soils in percentage of clay particles, and exchangeable Na content. E. grandis plantation was found improving soil nutrients and total carbon as compared with that of its adjacent submontane rain forest.展开更多
The aim of the study was to assess the impact of E. camaldulensis plantation established in a semi-arid area on native woody plants diversity and density. Nested quadrant plot design, having an area of 15 m × 15 ...The aim of the study was to assess the impact of E. camaldulensis plantation established in a semi-arid area on native woody plants diversity and density. Nested quadrant plot design, having an area of 15 m × 15 m used to collect data. Totally, 37 species at the plantation and 30 species at the native woodland, belonging to 24 families, identified. Species diversity (H′) was 1.57 at the plantation and 2.09 at the woodland forest. As for density of understory woody plants (height ≥ 1 m) the plantation forest harbored 6, 604 stems/ha while the native woodland had 7, 347 stems/ha. Seedling density (height Dodonaea angustifolia and other native species important for soil conservation, timber, bee forage and medicinal use.展开更多
文摘Published results on the growth interactions of non-nitrogen fixing mixed plantations species, and their impact on the regeneration of woody plants are scant. This paper addresses the growth interactions of pure and mixed plantations of Eucalyptus camaldulensis and Cupressus lusitanica and their impact on the regeneration of woody plants in relation with light. Data on the regenerated woody plants, individual characteristics of the plantation species and light reaching under the canopies were collected using sample plots (n = 4) with a size of 20 m × 20 m for each plantation type. The result showed that, E. camaldulensis was suppressing the growth of C. lusitanica while its growth was favored when it was mixed with C. lusitanica (p < 0.05). There were no significant differences between the pure and mixed plantations in their diversity and density of undergrowth woody plants (p > 0.05). Density of plantation trees were found not having a significant relationship with diversity of species (p = 0.801). There was a significant but not direct relationship between light reached in the understory of the canopies and diversity of species in the plantations (p = 0.027). Overall, the result indicated that both the pure and the mixed plantations were favoring the recruitment of woody plants.
基金supported by the Canadian International Development Agency (CIDA)
文摘A study was conducted to evaluate the status of soil nutrients under E. grandis plantation in comparison with that in its adjacent submontane rain forest. Twenty sequare plots, with an area of 20 m×20 m for each, were established in both of E.grandis plantation and its adjacent sub-montane rain forest, independently. Soil samples were collected from each square plot, at five points （at the four comers and at the center） of each plot. The collected soil samples were mixed to make a composite and representative sample for each plot, independently. The analyses were done in a soil laboratory following appropriate methods. The analysis result indicated that there were no significance differences between E. grandis plantation and its adjacent sub-montane rain forest in the level of major soil nutrients （total N, available P, exchangeable K, Ca and Mg）, pH and total carbon of soils （p 〈 0.05）. There were significance differences between two sites of forest soils in percentage of clay particles, and exchangeable Na content. E. grandis plantation was found improving soil nutrients and total carbon as compared with that of its adjacent submontane rain forest.
文摘The aim of the study was to assess the impact of E. camaldulensis plantation established in a semi-arid area on native woody plants diversity and density. Nested quadrant plot design, having an area of 15 m × 15 m used to collect data. Totally, 37 species at the plantation and 30 species at the native woodland, belonging to 24 families, identified. Species diversity (H′) was 1.57 at the plantation and 2.09 at the woodland forest. As for density of understory woody plants (height ≥ 1 m) the plantation forest harbored 6, 604 stems/ha while the native woodland had 7, 347 stems/ha. Seedling density (height Dodonaea angustifolia and other native species important for soil conservation, timber, bee forage and medicinal use.
