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在西部海湾沿海平原,对七种整地处理和五类土壤、施肥或不施肥的山地火炬松人工林的生产力作了试验。栽后12年,砍伐—焚烧—耙耕和剪裁—堆行—耙耕处理的,普遍获得了最大的断面积(每英亩112平方英尺),但砍伐—焚烧—耙耕处理的生产木材最多(每英亩2109立方英尺)。在砍伐和焚烧之后增加耙耕处理的,比仅只砍伐—焚烧处理的每英亩增加了394立方英尺的产量。林下喷洒除草剂和剪截—堆行的产量最低。粉砂土、慢渗透粘土和极慢渗透粘土的断面积较高(每英亩105平方英尺)。其中,粉砂土和慢渗透粘土的材积生长量较高(每英亩为1878立方英尺)。产量最低的立地为砾质底土。磷肥一般不影响火炬松的产量。
In the western coastal plains, the productivity of seven Pinus taeda plantations with or without soil fertilization and five types of soil preparation were tested. The largest cross-sectional area (112 square feet per acre) was generally obtained during the 12 years after harvesting - incineration - harrowing and cropping - heaping - harrowing, but most of the production of timber was from deforestation - harrowing 2109 cubic feet per acre). An increase of 394 cu. Ft. Per acre compared to Mere Felling - Incineration only increased after harvesting and burning. Herbicide spray and cut-off - the lowest yields were found. Silty sand, slow-penetrating clays, and extremely slow-penetrating clays have high cross-sectional areas (105 square feet per acre). Of these, silt and slow-infiltrating clays have high volumes (1878 cubic feet per acre). The lowest production site for gravel subsoil. Phosphate generally does not affect the production of loblolly pine.