摘要
[目的]探究黄土高原子午岭林区不同密度人工油松林枯落物的水源涵养功能,为该区功能导向型林分改造提供理论依据。[方法]于2021年8月在甘肃省合水县子午岭连家砭林场选取6种不同林分密度(2 222,3 200,4 802,6 250,7 503,9 286株/hm^(2))的油松人工林为研究对象,采用坐标综合评价法对不同密度油松林枯落物的水源涵养功能进行评价。[结果](1)油松林枯落物的厚度和蓄积量分别介于2.78~7.30 cm和14.97~52.41 t/hm^(2),两者变化趋势均呈“单峰型”,峰值出现在林分密度4 802株/hm^(2);(2)林分密度3 200株/hm^(2)的枯落物最大持水率(192.98%)和有效拦蓄率(152.04%)较高,而林分密度4 802株/hm^(2)的枯落物的最大持水量(101.46 t/hm^(2))和有效拦蓄量(67.92 t/hm^(2))表现优良,且半分解层在枯落物降水拦蓄过程中起主要作用;(3)枯落物持水率(量)、吸水速率与浸水时间分别呈对数函数[R^(2)>0.956(0.962)]和幂函数(R^(2)>0.998)关系;(4)油松林枯落物水源涵养功能发挥较好的林分密度为4 802株/hm^(2)。[结论]仅考虑油松林枯落物的水源涵养功能,油松林密度应调控至4 800株/hm^(2)。后续应加强对油松林林冠层及土壤层的研究,并综合考虑土壤水分植被承载力及油松林水分利用规律等,最终确定油松林水源涵养功能发挥最优的林分密度。
[Objective] The water conservation function of litters of artificial Pinus tabuliformis forests in the Ziwuling forest region of the Loess Plateau was determined in order to provide a theoretical basis for function-oriented stand improvement.[Methods] In August 2021,artificial Pinus tabuliformis forests with six stand densities(2 222,3 200,4 802,6 250,7 503,9 286 plants/hm^(2)) were selected in the Lianjiabian Forest Farm in Ziwuling,Heshui County,Gansu Province.The coordinate comprehensive evaluation method was used to evaluate the water conservation function of P.tabuliformis forests.[Results](1) The thickness and volume of litters ranged from 2.78 to 7.30 cm and from 14.97 to 52.41 t/hm^(2),respectively.With the increase of stand density,the thickness and volume of litters showed a “single peak” change,with the peak appeared at 4 802 plants/hm^(2).(2) The maximum water-holding rate(192.98%) and effective interception rate(152.04%) of litter for the 3 200 plants/hm^(2) stand were higher,while the maximum water-holding capacity(101.46 t/hm^(2)) and effective interception amount(67.92 t/hm^(2)) of litter for the 4 802 plants/hm^(2) stand were excellent.The semi-decomposed layer played a major role in the precipitation interception process of litters.(3) The water-holding rate/amount,water absorption rate,and soaking time of litters showed logarithmic responses(R^(2)>0.956,0.962) and a power function response(R^(2)>0.998),respectively.(4) The water conservation function of litters was better when the density of the P.tabuliformis forest was 4 802 plants/hm^(2).[Conclusion] When only considering the water conservation function of litters of an artificial P.tabuliformis forest,the density of the forest should be 4 800 plants/hm^(2).In the future,research on the canopy and soil layer of the P.tabuliformis forest should be strengthened.The soil moisture vegetation bearing capacity and the water utilization law of the forest should be comprehensively considered to determine the stand density of the forest that provides the best water conservation function.
作者
孙于卜
欧晓彬
陈轲林
马文昌
林飞
王智威
龚磊
Sun Yubo;Ou Xiaobin;Chen Kelin;Ma Wenchang;Lin Fei;Wang Zhiwei;Gong Lei(College of Life Sciences and Technology,Longdong University,Qingyang,Gansu 745000,China;Gansu Key Laboratory of Protection and Utilization for Biological Resources and Ecological Restoration,Qingyang,Gansu 745000,China;Gansu Ziwuling Ecological System Observation and Research Station,Qingyang,Gansu 745000,China)
出处
《水土保持通报》
CSCD
北大核心
2022年第3期8-15,共8页
Bulletin of Soil and Water Conservation
基金
陇东学院博士资助项目“增温对陇东黄土高原人工草地水土保持效应的影响机制”(XYBY202002)
甘肃省自然科学资助项目(21JR11RM042)
甘肃省高等学校创新资助项目(2021B-273)。
关键词
子午岭
密度梯度
枯落物
水源涵养功能
综合评价
Ziwuling forest
density gradient
litters
water conservation function
comprehensive evaluation
