【作者】 孙明学；

【导师】 马履一；

【作者基本信息】 北京林业大学 ， 森林培育， 2011， 博士

【摘要】 本文以“3S”技术和数学统计软件为主要技术手段,根据1974-2004年30多年来发生的各类火灾的基础数据,绘制30年塔河林业局森林火灾火烧迹地分布图,结合该地区地理信息系统,将火点分布图与不同类型专题图相叠加,分析了各影响因子与塔河林业局林火的关系,并以该地区的不同时期发生不同火烧强度的火烧迹地为研究对象,研究不同林火强度对不同林型下植被更新及土壤环境的影响,并根据不同经营目标,选择合适的森林植被更新恢复模式,缩短火后森林生态系统恢复时间,提高森林恢复质量。研究结果如下：(1)方差分析结果表明,火烧年限对土壤物理性质如含水率,容重和孔隙度影响显著,而火烧强度对土壤含水率和容重的影响无明显的规律性,但各火烧迹地数据随火烧强度呈现出的变化趋势表明火烧可以使土壤结构变紧实。(2)重度火烧对土壤有机质和速效磷含量的增加有一定的促进作用,并使土壤中水解氮的含量呈增加趋势,但随着年限的增加,速效磷的含量下降,速效钾的含量呈不规律变化；中度的火烧有利于土壤中全氮的增加,轻度火烧和中度火烧使土壤中水解氮的含量有所下降,土壤速效钾含量呈现逐年增加的趋势。经过不同年限和不同强度火烧后的铜、锌、铁、锰含量呈现出无规律的变化。但土壤中的铜和铁存在着一定的相关性,其含量经过不同强度的火烧后在各年限上所表现出来的变化趋势非常相似。(3)不同林型乔木更新能力由大到小的顺序为：草类落叶松林>落叶松白桦林>杜香落叶松林>杜鹃落叶松林>坡地落叶松林>杜鹃樟子松林；不同火烧强度对不同树种的更新有很大影响,大多数重火烧迹地将在很长一段时间内形成以杨桦为主的阔叶林；中度火烧初期更新最初形成以杨桦为优势树种的阔叶林,后逐渐演变为针阔混交林；轻度火烧有利于针叶林的更新。(4)不同火烧强度对植被更新数量的影响在各林分类型有所不同。杜鹃落叶松林不同火烧强度下与为火烧前植被种类数量相差不大；落叶松白桦林林型与坡地落叶松林型火烧后植物种类明显增加；各林分类型中乔木层和灌木层盖度随火后恢复时间的推移呈升高的趋势,而草本层盖度则随时间的推移而呈下降的趋势；随着火烧强度的增大,高频物种所占的比例降低,植物分布的均匀性显著下降。(5)不同火烧迹地应采取不同的森林的恢复途径：经营条件和立地条件较好的区域应该采用人工植苗更新；经营条件差,火烧面积较大的区域,森林更新恢复很大程度上要依赖于天然更新程度。(6)针叶林遭轻度火烧后,林内环境变化不大；在中度火烧迹地上,针叶林的天然更新情况是比较差的,经过很长时间的恢复阔叶树将会占有很大的比例；重度火烧后的森林,必须加大人工促进更新的力度,缩短植被恢复所需要的时间。(7)根据塔河林业局火烧迹地上5个主要林型：杜鹃落叶松林、草类落叶松林、杜香落叶松林、杜鹃樟子松林和落叶松白桦林林型特点,分析不同林分类型在不同火烧强度下植被及土壤理化性质的变化情况,提出了相应的更新措施和技术。(8)火烧迹地上落叶松和樟子松人工更新现状调查结果表明,人工更新比天然更新对土壤结构、植被状况的改造具有更明显的效果,植被恢复时间更短。以商品林和生态公益林为不同的培育目标,提出塔河林业局火烧迹地人工更新技术,并提出了落叶松和樟子松两个人工更新主要树种的四种更新模式。本文可从理论上完善国内在林火对植被恢复和土壤环境影响等内容。在实践中,可为合理有效的确定火后森林植被恢复模式,加速火后被破坏森林的恢复,制定有效的森林经营措施对策,提供可靠的科学依据。更多还原

【Abstract】 Some technologies such as Remote Sensing, Geographic Information System and mathematical statistical methods were used in this paper. The fire area distribution map of Tahe forestry bureau in the past 30 years were plotted based on the fire base data from 1974 to 2004. The relationship between influence factors and forest fire was analyzed according to the overlay of fire distribution map and different thematic map. The vegetation regeneration and physical and chemical characteristics variety of soil was also studied in the fire area after the fire of different intension and time interval in different forest type to select proper forest recovery mode according to different cultivation goal, shorten recovery time and improve forest recovery quality.The time factor is the main effect of forest fire that can affect soil moisture content, bulk density and porosity significantly. There no obvious rules of soil moisture and porosity affected by fire intension. The data indicates that fire can make soil structure more tightened.Severely burning can promote the increasing of soil organic matter, available phosphor and hydrolysable nitrogen. But available phosphor decreased with the process of time. There is no obvious rule for soil available potassium. Moderate burning is benefit for the increasing of total nitrogen. Lightly and moderate burning can reduce the soil hydrolysable nitrogen and increase the available potassium. The Cu, Zn, Fe, Mn in soil of the burned area after different time interval and fire intensity have no obvious rules. But the Cu in soil is related with the Fe in soil. They have similar variety tendency in different fire interval and fire intensity.The regeneration degree is different in different forest type, Ass·Herbage-Larix gmelini forest is highest and Ass·Rhododendron dauricum-Pinussylvestrisvar mongolica is lowest. Fire intensity can affect the regeneration of different tree species. The broadleaved forest of birth and poplar appeared in most severely burned area. In the moderately burned area the broadleaved forest of birth and poplar was firstly formed and gradually evolved to mixed forest of coniferous and broadleaved. Lightly burning is benefit for the regeneration of coniferous.The effect of fire intensity on plant type is different in different forest type. The plant type number has no difference among the burned area suffered by different fire intensity in Ass.Rhododendron dauricum-Larix gmelini forest but in Larix gmelini-Populus and slope-Larix gmelini forest, the plant type number increased obviously after the fire. The coverage of arbor and shrub in all forest increase gradually, but herbage coverage decrease after the fire. With the increase of fire intensity, the ratio of high-frequency plant and the equality of plant distribution decreased. Different plant regeneration mode selection should be adopted in different burned area. Artificial sapling regeneration should be performed in the area with good management and site conditions. In the area with poor management conditions and large burned area, the forest regeneration mainly depends on the natural regeneration.The environment in conifer forest has no obvious difference after lightly burning. Its natural regeneration is poor in moderately burned area and broad-leaved species will account for a large ratio after long recovery. The forest in high burned area should increase artificial approach to promote nature regeneration to shorten plant recovery time.According to the characteristic of 5 main forest type in the burned area of Tahe forest bureau, this paper analyzes the variance of plant and soil property of different forest after the fires with different intensity, puts forward relevant regeneration measure and technique.The actuality investigation of artificial regeneration on the burned area of Larix gmelini and Pinussylvestrisvar mongolica indicates that artificial regeneration has obviously effect on the rebuilding of soil structure and plant conditions and has shorter plant recovery time compared with nature regeneration. This paper puts forward the artificial technique of burned area in Tahe forestry bureau according to different cultivation goals of merchandise forest and ecology-benefit forest. It also puts forward 4 artificial regeneration modes for the 2 tree species.This paper can perfect the theory of fire time and space distribution, the effect of fire on plant recovery and soil environment. It also can provide scientific basis for determining reasonable and effective forest recovery mode, quickening up the recovery of destroyed forest, and establishing effective forest management measure.更多还原