不同经营措施对冀北山地油松林分水源涵养功能的影响

以河北省黄土梁子林场油松林为研究对象,设置4种不同经营措施(抚育间伐、天然更新幼林抚育、抚育+林冠下造林、更新采伐)人工林样地,采用室内浸水法和环刀浸泡法,对样地内枯落物的现存量、持水量以及土壤物理性质等进行测定,并对其水源涵养能力进行研究,以期为冀北山地油松林分的森林经营提供依据。结果表明,枯落物现存量变动范围在8.02~15.90 t/hm^(2),由大到小依次为:更新采伐>抚育间伐>天然更新幼林抚育>抚育+林冠下造林;更新采伐下枯落物最大持水量最高,为47.72 t/hm^(2),最大持水率最高,为219.10%;土壤容重均值变化范围在1.00~1.39 g/cm^(3),其中抚育+林冠下造林土壤容重最大为1.39 g/cm^(3),抚育间伐土壤容重最小为1.00 g/cm^(3);土壤总孔隙度变动范围在25.72%~61.41%,由大到小依次为:更新采伐>抚育间伐>天然更新幼林抚育>抚育+林冠下造林;最大持水量变动范围在273.56~896.21 t/hm^(2),由大到小依次为:更新采伐>天然更新幼林抚育>抚育间伐>抚育+林冠下造林,其中更新采伐下的土壤最大持水量是抚育+林冠下造林的1.84倍。综合表明,更新采伐措施下油松林分水源涵养能力最好。

Study on the influence of forest management on the water conservation capacity of Pinus tabulaeformis in mountain area of northern Hebei Province

Taking the Pinus tabuliformis forest in the Huangtuliangzi Forest Farm in Hebei Province as the research object, four different management measures(tending thinning, natural regeneration young forest tending, tending + under-canopy afforestation, and regeneration logging) were set up as plantation plots. The water immersion method and the ring knife immersion method were used to measure the existing amount, water holding capacity and soil physical properties of the litter in the sample plot, to study the water conservation capacity, in order to provide information for the forest management of the P. tabuliformis in mountain area of northern Hebei Province. The results showed that the variation range of litter volume was 8.02-15.90 t/hm², and the order from large to small was: renewing cutting > tending and thinning > natural regenerating young forest tending > tending + afforestation under the canopy; The maximum water holding capacity of litter was the highest under the renewal cutting, which was 47.72 t/hm², and the maximum water holding capacity was the highest, which was 219.10%; The variation range of soil bulk density was 1.00-1.39 g/cm³, of which the maximum soil bulk density under tending + canopy was 1.39 g/cm³, the minimum soil bulk density of tending and thinning was 1.00 g/cm³; The variation range of total soil porosity was 25.72% to 61.41%, and the order from large to small was: renewal cutting> tending thinning> natural renewal young forest tending> tending + afforestation under the canopy; The variation range of maximum water holding capacity ranged from 273.56-896.21 t/hm², and the order from large to small was: regeneration cutting> natural regeneration young forest tending> tending and thinning> tending + afforestation under the canopy, among which the maximum soil water holding capacity under regeneration cutting was tending + afforestation under the canopy 1.84 times. The comprehensive results showed that the water conservation ability of P. tabuliformis was the best under the renewed logging measures.