Search

This study aimed to explore the effects of thinning years on the water holding capacity of litter layer and soil layer in Chinese fir forest, thus to provide a scientific basis for evaluating the response of water conservation function of Chinese fir forest to thinning. In Jingning County, southwest Zhejiang Province, the Chinese fir forest with thinning for 1 year, 3 years, 8 years and unthinning was selected as the research object, and the litter and soil samples were collected. Then, the moisture content, water holding capacity, soil bulk density, non-capillary porosity of litter were analyzed and measured, and the relevant indexes were calculated. The results showed that there was no significant difference in the litter stock on hand of Chinese fir forest among different thinning years (P>0.05). The relationship between litter water holding capacity, water holding rate and water immersion time was in accordance with logarithmic function and power function, respectively. The maximum water holding capacity, maximum retention rate and effective retention rate of litter layer in Chinese fir forest with thinning for 8 years were significantly higher than those in the unthinned forest (P<0.05). The maximum water holding capacity and effective retention rate of litter layer in Chinese fir forest with thinning for 3 years and 8 years were significantly higher than those in unthinned forest (P<0.05). After thinning for 8 years, the soil bulk density of 0-10 cm soil layer in Chinese fir forest was significantly decreased (P<0.05), the non-capillary porosity was significantly increased, and the non-capillary water holding capacity was significantly increased by 22.4% (P<0.05). However, there was no significant effect on the related indicators of soil water storage performance in 10-30 cm soil layer (P>0.05). In conclusion, the water conservation function of litter layer and soil layer in Chinese fir forest was enhanced with the extension of thinning years. [ABSTRACT FROM AUTHOR]

By taking the public welfare forest land in Jiangshan City of Zhejiang Province as the research object, based on the measured data of fixed sample plots and sublot of public welfare forest, the water conservation capacity and value of litter layer and soil layer in different forest stands were quantitatively measured and analyzed. The results showed that the effective interception amount of litter in different forest types of public welfare forest in Jiangshan City was coniferous and broad-leaved mixed forest>broad-leaved forest>Chinese fir forest>pine forest>moso bamboo forest. In the same depth of soil layer, the difference of soil physical properties and water holding capacity was not obvious. The soil layer contributed more than 99 % of the water conservation quantity of forest land. The order of water conservation ability was coniferous and broad-leaved mixed forest>broad-leaved forest>moso bamboo forest> Chinese fir forest>coniferous mixed forest>pine forest>shrub forest. The total annual water conservation quantity of public welfare forests in the whole city was 18 7,7869 million tons, with the value quantity of 1.979 billion yuan. The water conservation quantity per unit area was about 2813 t ⋅ hm-2, and the value quantity per unit area was about 29,700 yuan ⋅ hm-2. In Jiangshan City, the water conservation capacity of public welfare forest was stronger in the east, while the water conservation capacity of public welfare forest in the north was relatively weak. [ABSTRACT FROM AUTHOR]