1 材料与方法
1.1 研究区域概况
1.2 样地选择
表1 3种天然林林分基本特征Tab. 1 Basic characteristics of three natural forests |
| 森林类型 Forest types | 优势树种 Dominant Species | 林分密度 Stand density /(株·hm-2) | 林龄 Stand age/a | 平均胸径 Mean DBH /cm | 平均树高 Mean tree height/m | 郁闭度 Canopy density | 海拔 Elevation /m | 坡向 Aspect | 坡度 Gradient/° |
|---|---|---|---|---|---|---|---|---|---|
| 米槠林 | 米槠、鹿角杜鹃 | 1700 | 120 | 15.3 | 10.3 | 0.9 | 600 | S | 45 |
| 马尾松林 | 马尾松、檵木 | 2100 | 120 | 11.6 | 13.3 | 0.7 | 600 | S | 35 |
| 闽桦-闽楠林 | 闽桦、闽楠 | 1100 | 130 | 17.4 | 12.5 | 0.9 | 600 | NE | 35 |
1.3 野外调查
1.4 生物多样性计算
1.5 数据处理
2 结果与分析
2.1 3种林分不同层次群落特征差异
表2 3种林分乔木层、灌木层、草本层和藤本层特征值Tab. 2 Parameters of tree layer, shrub layer, herb layer and liana layer of three forests |
| 层 Layer | 特征参数 Parameter | 米槠林 Castanopsis carlesii forest | 马尾松林 Pinus massoniana forest | 闽桦-闽楠林 Betula fujianensis and Phoebe bournei mixed forest |
|---|---|---|---|---|
| 乔木层 | 树高/m | 10.30±1.00a | 11.60±1.88a | 12.50±1.02a |
| 胸径/cm | 15.30±0.46ab | 13.30±2.15b | 17.40±0.75a | |
| 枝下高/m | 5.92±0.49a | 6.70±0.91a | 6.46±0.80a | |
| 灌木层 | 株高/m | 0.45±0.15b | 0.78±0.21a | 0.76±0.12a |
| 地径/cm | 0.32±0.14b | 0.73±0.25a | 0.54±0.25ab | |
| 冠幅/m | 0.18±0.07b | 1.70±0.64a | 0.43±0.20b | |
| 草本层 | 多度 | 24.00±8.29c | 72.50±15.96a | 45.00±13.54b |
| 盖度/% | 2.60±1.55c | 8.60±0.92a | 5.30±1.86b | |
| 高度/cm | 20.10±6.19ab | 18.20±3.95b | 33.00±13.24a | |
| 藤本层 | 多度 | 53.80±12.60a | 22.80±12.9b | 44.30±14.30a |
| 盖度/% | 0.26±0.04b | 0.24±0.10b | 0.66±0.20a | |
| 高度/m | 0.57±0.15a | 1.16±0.72a | 1.80±1.36a |
注:数据为平均值±标准误;同行不同小写字母表示差异显著(P<0.05)。 | |
Note: The data are mean ± SE; different lowercase letters in the same row indicate significant difference (P<0.05). |
2.2 3种林分不同层次群落物种多样性特征比较
表3 3种林分物种多样性、均匀度和丰富度指数Tab. 3 Species diversity, evenness and richness indexes of three forests |
| 层 Layer | 物种多样性指数 Species diversity index | 米槠林 Castanopsis carlesii forest | 马尾松林 Pinus massonianaforest | 闽桦-闽楠林 Betula fujianensis and Phoebe bournei mixed forest |
|---|---|---|---|---|
| 乔木层 | Gleason指数(G) | 2.92±0.57a | 1.50±0.24b | 2.37±0.50a |
| Margalef指数(M) | 3.96±0.88a | 1.82±0.36b | 3.69±0.89a | |
| Simpson指数(D) | 0.85±0.02a | 0.58±0.06b | 0.88±0.03a | |
| Shannon-wiener指数(H) | 2.30±0.18a | 1.31±0.18b | 2.38±0.28a | |
| Pielou指数1(Jsw) | 0.81±0.03b | 0.60±0.07c | 0.90±0.03a | |
| Pielou指数2(Jsi) | 0.90±0.02a | 0.66±0.08b | 0.95±0.02a | |
| 灌木层 | Gleason指数(G) | 9.44±1.01a | 4.48±0.81b | 8.54±1.10a |
| Margalef指数(M) | 8.52±0.97a | 4.95±1.30b | 8.23±1.17a | |
| Simpson指数(D) | 0.91±0.02a | 0.88±0.04a | 0.92±0.03a | |
| Shannon-wiener指数(H) | 3.08±0.14a | 2.57±0.36b | 3.16±0.24a | |
| Pielou指数1(Jsw) | 0.79±0.01a | 0.81±0.07a | 0.83±0.04a | |
| Pielou指数2(Jsi) | 0.93±0.02a | 0.92±0.04a | 0.94±0.03a | |
| 草本层 | Gleason指数(G) | 1.41±0.69b | 1.31±0.76b | 4.83±1.54a |
| Margalef指数(M) | 0.96±0.58b | 0.63±0.50b | 3.05±0.93a | |
| Simpson指数(D) | 0.49±0.10b | 0.33±0.26b | 0.86±0.40a | |
| Shannon-wiener指数(H) | 0.88±0.29b | 0.64±0.53b | 2.18±0.29a | |
| Pielou指数1(Jsw) | 0.76±0.06a | 0.54±0.17b | 0.89±0.01a | |
| Pielou指数2(Jsi) | 0.73±0.06a | 0.48±0.25b | 0.95±0.24a | |
| 藤本层 | Gleason指数(G) | 1.04±0.24b | 1.04±0.33b | 1.84±0.52a |
| Margalef指数(M) | 1.29±0.50b | 1.90±0.62ab | 2.43±0.61a | |
| Simpson指数(D) | 0.72±0.06a | 0.73±0.08a | 0.77±0.11a | |
| Shannon-wiener指数(H) | 1.41±0.21a | 1.49±0.34a | 1.79±0.37a | |
| Pielou指数1(Jsw) | 0.84±0.08a | 0.89±0.05a | 0.79±0.11a | |
| Pielou指数2(Jsi) | 0.88±0.06a | 0.90±0.05a | 0.85±0.11a |
注:数据为平均值±标准误;同行不同小写字母表示差异显著(P<0.05)。 | |
Note: The data are mean ± SE; different lowercase letters in the same row indicate significant difference (P<0.05). |
2.3 3种林分群落特征与物种多样性的耦合关系
图1 林分群落特征对物种多样性影响的CCA二维排序箭头代表林分特征,为解释变量,实心质点为物种多样性指数,为响应变量。T-G:乔木层Gleason指数;T-M:乔木层Margalef指数;T-D:乔木层Simpson指数;T-H:乔木层Shannon-wiener指数;T-Jsw:乔木层Pielou指数1;T-Jsi:乔木层Pielou指数2。S-G:灌木层Gleason指数;S-M:灌木层Margalef指数;S-D:灌木层Simpson指数;S-H:灌木层Shannon-wiener指数;S-Jsw:灌木层Pielou指数1;S-Jsi:灌木层Pielou指数2。H-G:草本层Gleason指数;H-M:草本层Margalef 指数;H-D:草本层Simpson指数;H-H:草本层Shannon-wiener指数;H-Jsw:草本层Pielou指数1;H-Jsi:草本层Pielou指数2。L-G:藤本植物Gleason指数;L-M:藤本植物Margalef指数;L-D:藤本植物Simpson指数;L-H:藤本植物Shannon-wiener指数;L-Jsw:藤本植物Pielou指数1;L-Jsi:藤本植物Pielou指数2。 Fig. 1 CCA two-dimensional ranking diagram of impact of stand community characteristics on species diversity Arrows represent stand characteristics, and are explanatory variables. The solid particles are species diversity index and response variables. T-G: Gleason index of tree; T-M: Margalef index of tree; T-D: Simpson index of tree; T-H: Shannon-wiener index of tree; T-Jsw: Pielou index 1 of tree; T-Jsi: Pielou index 2 of tree. S-G: Gleason index of shrub; S-M: Margalef index of shrub; S-D: Simpson index of shrub; S-H: Shannon-wiener index of shrub; S-Jsw: Pielou index 1 of shrub; S-Jsi: Pielou index 2 of shrub. H-G: Gleason index of herb; H-M: Margalef index of herb; H-D: Simpson index of herb; H-H: Shannon-wiener index of herb; H-Jsw: Pielou index 1 of herb; H-Jsi: Pielou index 2 of herb. L-G: Gleason index of liana; L-M: Margalef index of liana; L-D: Simpson index of liana; L-H: Shannon-wiener index of liana; L-Jsw: Pielou index 1 of liana; L-Jsi: Pielou index 2 of liana. |
表4 3种林分群落特征与CCA排序前两轴相关系数Tab. 4 Correlation coefficient between community characteristics of three forests and first two axes of CCA ranking |
| 层 Layer | 特征参数 Parameter | 米槠林 Castanopsis carlesii forest | 马尾松林 Pinus massonianaforest | 闽桦-闽楠林 Betula fujianensis and Phoebe bournei mixed forest | |||
|---|---|---|---|---|---|---|---|
| CCA1 | CCA2 | CCA1 | CCA2 | CCA1 | CCA2 | ||
| 乔木层 | 树高TH/m | -0.366 | 0.915 | -0.036 | -0.139 | 0.774 | 0.397 |
| 胸径TDBH/cm | 0.991 | -0.067 | 0.176 | 0.435 | -0.709 | 0.578 | |
| 枝下高TCBH/m | -0.604 | 0.759 | 0.248 | 0.121 | 0.634 | -0.139 | |
| 灌木层 | 株高SH/m | -0.469 | -0.111 | 0.297 | 0.954 | 0.166 | -0.269 |
| 地径SGD/cm | -0.254 | -0.407 | -0.134 | 0.938 | 0.699 | 0.432 | |
| 冠幅SCD/m | 0.002 | -0.259 | 0.873 | 0.484 | 0.609 | 0.427 | |
| 草本层 | 多度HA | -0.982 | -0.153 | 0.127 | 0.655 | 0.998 | 0.018 |
| 盖度HC/% | 0.231 | -0.542 | 0.495 | -0.377 | 0.926 | 0.388 | |
| 高度HH/cm | 0.318 | 0.469 | -0.531 | -0.446 | -0.722 | 0.006 | |
| 藤本层 | 多度LA | -0.630 | 0.611 | -0.189 | -0.577 | -0.053 | 0.718 |
| 盖度LC/% | -0.667 | -0.505 | -0.806 | 0.297 | -0.005 | 0.973 | |
| 高度LH/m | -0.937 | -0.351 | -0.035 | -0.995 | -0.053 | 0.978 | |
