华北土石山区典型林分枯落物层和土壤层水源涵养能力研究

Water conservation capacity of litter layer and soil layer in typical forest stands in the North China rocky mountain area

    摘要
  • 摘要: 华北土石山区作为京津冀重要水源涵养地，其基岩以碎石母质为主，土层浅薄、持水能力较弱，加剧了森林生态系统林分结构单一、人工林水源涵养功能退化等问题，难以有效满足区域水资源安全保障需求．本研究在河北省保定市黄路元流域通过对比5种典型林分（板栗、刺槐、白杨、油松、侧柏）枯落物层和土壤层的水源涵养能力，为提升生态系统稳定性、促进生态修复及水源涵养林营建提供科学依据．通过野外调查采集样品，采用称量法、室内浸泡法、环刀法测定枯落物层厚度、最大持水量、有效拦蓄量及土壤容重、总孔隙度、饱和蓄水量等核心水文指标，结合回归分析法分析枯落物层和土壤层持水动态特征，进一步运用熵权法对上述指标进行客观赋权综合评估不同林分水源涵养能力．结果显示：枯落物层中，板栗林总厚度（5.41 cm）和最大持水量（15.35 t·hm2）均显著高于其他林分（P<0.05），其未分解层持水量占比达60%以上；白杨林枯落物总厚度（4.96 cm）与刺槐持平，显著高于油松（4.04 cm）和侧柏（4.55 cm），（P<0.05），最大持水量（14.7 t·hm2）仅次于板栗．5种林分枯落物持水量均随浸水时间呈对数增长（R2>0.9），且自然含水率与有效拦蓄量呈强负相关（r=−0.753，P<0.01）．土壤层中，板栗总孔隙度最大（30.3%），饱和蓄水量达3188 t·hm2，而刺槐土壤容重最高（1.43 g·cm−3），显著抑制持水能力（P<0.05）；侧柏、油松的土壤有效蓄水量仅为板栗的60%~70%．综合评估显示，水源涵养能力从高到低排序依次为：板栗（0.23）、白杨（0.22）、刺槐（0.2）、油松（0.18）、侧柏（0.17）．因此，可优先选择板栗和白杨作为核心树种，在浅山流域及坡耕地修复区推广，发挥其枯落物与土壤层的协同持水优势；侧柏和油松可作为乡土伴生树种，在石质山区混交种植，兼顾生态适应性与水源涵养功能．

     

    Abstract: The North China mountainous region is a vital water conservation area for the Beijing-Tianjin-Hebei region． However, the forest ecosystems struggle to effectively meet regional water security demands due to issues such as monotonous stand structures and degraded water conservation functions in planted forests． In this study water conservation capacities of litter layers and soil layers across five typical forest stands (chestnut, locust, populus, pinustabulaeformis, Thujaorientalis) were compared to enhance ecosystem stability, to promote ecological restoration, and to establish water conservation forests． Samples were collected in field surveys, hydrological effects of litter and soil layers were measured and analyzed (by weighing, laboratory soaking, ring-cutting, and regression analysis)． Water conservation capacity was evaluated in entropy weight analysis． Among litter layers, chestnut exhibited significantly higher total thickness (5.41 cm) and maximum water-holding capacity (15.35 t·hm2) than other stands (P<0.05), with undecomposed layer accounting for over 60% of water retention． Poplar litter total thickness (4.96 cm) equaled that of locust tree, significantly exceeding oil pine (4.04 cm) and Chinese juniper (4.55 cm) (P<0.05). Maximum water holding capacity (14.7 t·hm2) ranked only below chestnut． The water-holding capacity of litter in all five forest stands exhibited logarithmic growth with immersion time (R2 > 0.9), and natural moisture content showed a strong negative correlation with effective storage capacity (r = −0.753, P < 0.01). In the soil layer, chestnut exhibited the highest total porosity (30.3%) and saturated water storage capacity (3188t·hm²), while black locust had the highest soil bulk density (1.43 g·cm3), significantly inhibiting water-holding capacity (P<0.05)． The effective water storage capacity of Chinese juniper and Chinese pine was only 60%–70% that of chestnut． Comprehensive evaluation indicated that the water conservation capacity followed the rank of: chestnut (0.23) > poplar (0.22) > locust (0.2) > pine (0.18) > cypress (0.17)． Chestnut and poplar should therefore be prioritized as core tree species for promotion in shallow mountain watersheds and slope farmland restoration areas, leveraging their synergistic water retention advantages through litter and soil layers． Arborvitae and pine can serve as native companion species for mixed planting in rocky mountainous areas, to balance ecological adaptability with water conservation functions．

     

    • HTML全文
    • 参考文献(29)
    • 相关文章
    • 施引文献
  • 资源附件(0)

/

返回文章
返回