摘要
通过对杉木、马尾松、红荷木、格木四种人工林的三年定位研究,初步获得了四种林木对主要营养元素的生物吸收和归还特点、对土壤养分状况、水分状况、微生物状况和土壤酶活性的影响等一系列资料。初步阐明了四种林木凋落物的数量及主要营养元素含量,研究了四种林木凋落物的分解特点。从而为进一步研究林木混交提供了科学依据。研究表明,阔叶树种与针叶树种相比,在改善土壤理化性状、提高土壤生产力等方面都表现出明显的优点。
The artificial forests existing in southern subtropical China consist chiefly of China fir and pines. Continuous reforestation of coniferous trees has resulted in the deterioration of soil conditions and decreased the production of forestry. For improvement of the forest soil and production of forestry, a three-year location experiment on material cycling of the establishing artificial forests of Cunninghamia lanceolata, Pinus massoniana, Schima wallichii and Erythrophloeum fordii on lateritic red earth in Nanning was conducted. Results of the experiment showed that the four types of forest trees differed from each other both in characteristics of biological material cycling and in amounts of litter. The mean annual amount of litter of coniferous trees was less than 4t/ha, whereas that of broad leaf trees such as Schima wallichii and Erythrophloeum fordii was more than 6.3t/ha. In litter coniferous trees, Ca, Mg and Si as its essential nutrient elements, made up 60—80% of total ash、 these elements being usually no tlacking in soil itself, while the litter of broadleaf trees contained considerable amounts of N, P and K in addition to Ca, Mg and Si. Each year, China fir returned to the soil 118.5 kg of ash and nitrogen per hectare in the form of litter, Pinus massoniana 79.5 kg/ha, Schima wallichii 168.1 kg/ha, and Erythrophloeum fordii 304.8 kg/ha. The litter of woods played a significant role in promoting water-retention ability of soil. It was estimated that the mean annual water-retention capacity of the litter under China fir, Pinus massoniana, Schima wallichii, Erythrophloeum fordii was 1.5t/ha, 1.8t/ha, 2.5t/ha, 3.2t/ha respectivety. Effect of different forest trees on both number and dominant species of micro-organisms in soil was distinct; it for example, although in the soils under coniferous trees, there were the highest contents of fungi actinomyces and bacteria; in the soil under broad leaf trees, there was the highest amount of mierobial biomass. At the same time, the variety and activity of soil enzymes were also influenced by different forest trees. It is indicated that broad leaf forests are litter in improvement of physical and chemical properties of soil and promotion of soil productivity, as compared with coniferous forests, therefore, the development of mixed forest of coniferous trees that provide timbers and broadleaf trees than can improve soil condition is a important measure for development of forestry in south China.
出处
《土壤学报》
CAS
CSCD
北大核心
1990年第3期250-261,共12页
Acta Pedologica Sinica
