临猗县不同林龄苹果林地枯落物及土壤水源涵养功能研究

Study on Water Conservation Function of Litter and Soil in Apple Tree Plantation of Different Stand Ages of Linyi

探讨不同林龄苹果林地枯落物和土壤水源涵养能力的变异特征,明确苹果林地的水分特征,对建立合理的果园管理制度等具有重要意义。以运城市临猗县不同林龄(4、6、15、30 a)苹果林地为研究对象,通过野外调查和室内试验,对苹果林地枯落物和土壤水源涵养能力进行定量描述和差异性研究。结果表明,4种林龄苹果林地枯落物层总蓄积量为0.82~2.09 t/hm^(2),最大持水量介于4.91~13.09 t/hm^(2),有效拦蓄量在3.36~9.38 t/hm^(2),随着林龄的增长,以上参数量均表现为先增大再减小的趋势,以15 a为最大。枯落物层持水量、吸水速率与浸水时间分别存在良好的对数和幂函数关系。在0~60 cm范围内,随着林龄的增长,苹果林地土壤容重逐渐减小,总孔隙度和最大持水量逐渐增加,以30 a为最大。随着土层加深,不同林龄苹果林地土壤容重呈现先增大再减小的趋势;除林龄4 a外,其余林龄土壤总孔隙度逐渐减小,但各土层之间差异性不显著。30 a苹果林地土壤最大持水量随土层加深逐渐降低,其余林龄呈现先减小再增加的趋势,均以0~10 cm土层持水量最大,20~40 cm土层最低。坐标综合评定法得出林龄在15 a时枯落物层和土壤层(0~60 cm)总水源涵养功能最强,30 a林龄次之,4 a林龄最弱。

To investigate the effects of different stand ages on the litter and soil water conservation ability in apple tree planta⁃tion,and clarify the water characteristics of apple tree plantation,is of great significance for establishing a reasonable orchard manage⁃ment system,consiolidating and expanding the achievements of poverty alleviation and realizing rural revitalization.Taking apple tree plantation of different stand ages(4,6,15 and 30 a)in Linyi County,Yuncheng City as the research object,this paper quantitatively described and studied the differences of litter and soil water conservation ability in apple tree plantation through field investigation and laboratory test.The results showed that:the total storage of the litter about the four stand ages in apple tree plantation ranged from 0.82 to 2.09 t/hm^(2),the maximum water holding capacity ranged from 4.91 to 13.09 t/hm^(2),and the water conservation capacity ranged from 3.36 to 9.38 t/hm^(2).With the increase of tree age,these parameters increased first and then decreased,and the maximum was 15 years old.There were good logarithmic and power function relationships between water holding capacity,water absorption rate and soaking time of litter layer respectively.Within the range of 0 to 60 cm,as the tree age increased,the soil bulk density decreased gradually,the total porosity and the maximum water holding increased gradually,and the maximum was 30 a.With the deepening of soil layer,the soil bulk density of apple tree plantation of different stand ages increased first and then decreased.Except 4 a,the total soil porosity of the remaining trees decreased gradually,but the difference between different soil layers was not significant.The maxi⁃mum soil water holding capacity of 30 a orchard gradually decreased with the deepening of the soil layer,and the other trees showed a trend of decreasing first and then increasing at the age of 0 to 10 cm soil layer,and the minimum water holding capacity at 20 to 40 cm soil layer.According to the coordinate comprehensive evaluation method,the performance of litter and soil water conservation capac⁃ity of different stand ages was the strongest at the age of 15 years,the second at the age of 30 years,and the weakest at 4 a years.