| Nowadays, there is a severe shortage of forest resource and timber supply nervous in our country, and the contradiction of supply and demand has become increasingly. At present, the plantation area in our country has been ranked in the world, there is a lot of mountainous regions in China, and this is an advantaged and favourable condition for constructing forest-paper and forest-board industrialization. Although the plantation reflects significant economic and social benefits while still exist in the disputes about ecological benefits. How to speed up the construction of artificial timber base, strengthen management, promote the tree growth, improve the yield and quality of timber will be an arduous task in the long-term that forestry industry facing. Eucalyptus (Eucalypt us spp) as south China main fast-grown forest tree species, until 2011, the area has reached 365 million hectares. In the management of eucalyptus stand on the word appeared such as reduced productivity, woodland soil degradation, soil fertility, ecological and decrease etc many production issues. How to solve and eventually avoid these problems arises, is the key field for research and development of eucalyptus plantation.This study research for forest stand, soil physical and chemical properties of different plantation age, different management measures of eucalyptus plantation forest in south seedlings base (slope, flat), Shiling wood farm (flat), got the following conclusions:(1) In the tree high growth, eucalyptus plantations for stump rot minder land is better than mechanical cultivation full cultivation; but DBH contrary, shown that mechanical cultivation full cultivation is superior, and were very significant differences. The growth of trees for different district in the same management measures (stump rot minder) also has significant difference.(2) With the growth of generation and age of Eucalyptus plantation, soil organic matter, hydrolysis nitrogen, rapidly-available potassium, exchangeable magnesium was increased; but available phosphorus and exchangeable calcium was highest in the first generation. Soil bulk density, porosity and capacity increased with forest age and have got different degrees improvement, explaining that in a relatively short period of time, soil physical property got improvement after forestation . However, variance analysis showed that, the influence of forest age to soil bulk density and capacity did not achieve significant level, which was very significant by soil depth.(3) The influence of soil physical and chemical properties in stump rot minder land and burned land (slope land).â‘ Soil physical properties showed that the forest land which is before foresting was better than one after foresting. Compared with two management measures we found: stump rot minder land was better than burned land which before foresting in soil bulk density and capacity; and for forestation after there were: stump rot minder land was better than burned land in soil bulk density and capacity in shallow soil layer (0~20cm); but burned land was better in deep soil layer (20~60cm).â‘¡Soil nutrient. The sequencing of soil pH value was: stump rot minder land>burned land>the land before forest cutting, show that cut or afforest measures made forest land tended to slant acerbity. Soil OM, TN and TK content was the richest in the stump rot reminder land and the poorest in the burned land; TP was the richest in the land before harvesting and the poorest in the stump rot minder land. For the secondary-nutrients, soil Ca content and Mg content of the surface soil were the richest in stump rot minder land; and Mg content of the middle layer was the richest in the land before forest cutting. For the trace elements, Fe, Mn, Zn and B content was the richest in stump rot minder land in addition to Cu was the richest in burned land; these three kinds of situations were no significant differences in microelements content except that B was very significant difference in 30~60cm for stump rot minder land with burned land and the land before forest cutting. Stump rot minder management measure was better than burned on slope land.(4) The influence of soil physical and chemical properties for before and after burning (flat).â‘ After burning, eucalyptus plantation forested will impact on shallow soil (0~20cm) on flat ground, the effect was positive, that was reduced soil bulk density, increased soil capacity and porosity and improved soil aeration and permeable performance, but the soil physical properties of before cutting land was better for the deep layer.â‘¡Soil pH values for before cutting land was higher than burned, and burned land tended to slant acerbity. Soil OM, TN, TP, TK and Zn content in burned land was richer than in before cutting land, indicated that burned could improve soil organic matter and major element content in the short term. And for soil total Ca, Mg and Fe, Mn, Cu, B content speaking, had the situation that burned land>before cutting land, namely that burned had no obvious promoting effect to improve secondary-nutrients and most of trace elements content.(5) The influence of soil physical properties for stump rot minder land and mechanical cultivation full cultivation land (The Shiling wood farm). In the overburden layer (0~10cm), we could find that except the soil bulk density and non-capillary porosity showed higher in stump rot minder land , other various indexes showed lower in stump rot minder land than CK; but the total indexes of middle soil layer (10~30cm) ,the soil bulk density,saturation moisture capacity and of the soil layer (30~40cm),and all the indexes except non-capillary porosity of deep soil layer (50~60cm) were all showed stump rot minder land was better than CK. |
PDF Full Text Request