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为了揭示云冷杉林生长季坑丘微立地上微气候因子的时空变化以及PPFD、RH、SWC与不同深度TS的相关性。2013年7—9月在小兴安岭谷地云冷杉林风倒区1.50 hm2的固定样地内,测定所有35对坑丘微立地(丘顶、丘面、坑底、坑壁)的光量子通量密度(PPFD)、空气相对湿度(RH)、地表土壤温度(TS0)、5 cm和10 cm深度的土壤温度(TS5和TS10),以及0~7.6 cm、0~12 cm和0~20 cm土壤含水量(SWC1、SWC2和SWC3)等微气候因子,并将完整立地(未受掘根干扰的完整林地)设为对照样地。比较5个不同微立地微气候因子的月变化以及PPFD、RH以及SWC对土壤温度(TS)的影响。结果表明:7—9月,坑丘微立地(丘顶、丘面、坑底、坑壁)的月均PPFD和TS0均为7月>8月>9月,月均RH以及TS5和TS10均为8月>7月>9月,月均SWC均为8最大;7—8月不同微立地月均PPFD大小顺序均为丘顶>丘面>坑底>完整立地,9月却为丘顶>丘面>完整立地>坑底>坑壁;7—9月,各微立地TS0大小顺序均为丘顶>丘面>完整立地>坑壁>坑底,而5 cm和10 cm均为丘顶>丘面>坑壁>完整立地>坑底;月均RH和月均SWC均为坑底>坑壁>完整立地>丘面>丘顶;7月丘顶的PPFD最大,为736.11μmol·m-2·s-1,完整立地最小,为25.46μmol·m-2·s-1,丘顶TS最高,为26.29℃,坑底TS最低,为5.13℃;浅层SWC大于较深层的,最大SWC出现在8月的坑底,为51.58%。相同微立地(丘顶、坑底、完整立地)PPFD与浅层TS的相关性大于较深层的土壤,TS0与PPFD呈正相关,与RH呈负相关。
In order to reveal the spatio-temporal variations of microclimate factors and the correlations of PPFD, RH, SWC and TS at different depths on the pits in the mound of fir spruce forest during the growing season. From July to September in 2013, the photon flux density (PPFD) of all 35 pairs of mound plots (hilltop, hilltop, pit bottom and pit wall) was measured in a fixed site of 1.50 hm2 in the fir forest of Xiaoxing’an Mountains. , Soil relative humidity (RH), soil surface temperature (TS0), soil temperature at 5 cm and 10 cm (TS5 and TS10) and soil moisture at 0 ~ 7.6 cm, 0 ~ 12 cm and 0 ~ 20 cm SWC1, SWC2 and SWC3), and the intact site (intact woodland without disturbing root) was set as the control sample. The monthly changes of five microclimate factors and the effects of PPFD, RH and SWC on soil temperature (TS) were compared. The results showed that the average monthly PPFD and TS0 of micro-plots (hilltop, hilltop, bottom and pit wall) from July to September were July> August> September, mean monthly RH, TS5 and TS10 The average monthly SWC was 8 months in August> July> September. The average monthly PPFD in different micro-terraces in July and August was in the order of hilltop> hillside> pit bottom> complete site, > Hillock> intact hill> pit bottom> pit wall. From July to September, the order of TS0 of each microclimate was hill top> hillock> complete stand> pit wall> pit bottom, while both 5 cm and 10 cm were mound Top> hillock> pit wall> intact hill> bottom of pit; monthly mean RH and monthly mean SWC were pit bottom> pit wall> complete stand> hilltop> hilltop; the maximum PPFD of hilltop in July was 736.11μmol · m -2 · s-1, and the minimum intact site was 25.46μmol · m-2 · s-1. The highest TS was 26.29 ℃ and the lowest TS was 5.13 ℃. The shallow SWC was larger than the deeper one The SWC appeared at the bottom of August at 51.58%. The correlation between PPFD and shallow TS in the same microlitre (hilltop, pit bottom and intact site) was greater than that in the deeper soil. TS0 was positively correlated with PPFD and negatively correlated with RH.