永利煤矿复垦区植物叶片和枯落物生态化学计量学特征

Ecological stoichiometry characteristics of leaves and litter in plant communities in the Yongli colliery reclamation area

为了明确煤矿复垦区植被恢复与重建以及不同物种的合理配置,以内蒙古永利露天煤矿复垦区不同植物群落叶片和枯落物为研究对象,通过对其碳(C)、氮(N)、磷(P)、钾(K)含量(质量含量)及生态化学计量学特征的研究,探讨煤矿复垦区植物养分状况及限制因子,同时研究叶片和枯落物之间的养分循环状况。结果表明:(1)不同植物类型叶片C含量变化较大,表现为乔木(侧柏537.96 g/kg)最大,草本(沙打旺423.73 g/kg)最小;N、P、K含量变化较小。枯落物中沙棘C含量(417.84 g/kg)显著高于沙打旺、柠条;N、P含量差异显著,氮含量表现为沙打旺(20.30 g/kg)最大,柠条最小,磷含量表现为沙打旺(1.57 g/kg)最大,沙棘最小;沙打旺K含量(6.31 g/kg)显著高于沙棘、柠条。叶片C、N、P、K含量高于枯落物。N、P、K的回收率分别为5.17%—50.16%、4.19%—6.41%、11.27%—23.24%,其中P回流率表现为沙打旺(6.41%)最大,柠条最小;K回流率表现为沙棘(23.24%)最大,柠条最小。(2)灌木、草本植物N/P>16,乔木类N/P<14,灌木类、草本类生长受制于P,乔木类生长受制于N。结合土壤C、N、P含量,建议在植被恢复初期种植豆科等先锋植物,随着土壤肥力的提高再逐步种植灌木、乔木。

The objective of this study was to clarify the ecological stoichiometry characteristics of leaves and litter in different plant communities in the Yongli colliery reclamation area. Leaves and litter were collected, and organic carbon （C）, total nitrogen （N）, total phosphorous （P）, and total potassium （K） content were measured.Plant nutrient values and restriction factors for the reclamation area were determined and nutrient cycling between leaves and litter was investigated. The results indicated that： （1） There were significant differences in leaf C content among the different plant types. C content was the highest in shrubs （Platycladus orientalis （L.） Franco, 537.96 g/kg） and the lowest in herbs （Astragalus adsurgens Pall., 423.73 g/kg）. Leaf N, P, and K content did not differ significantly between plant types. In contrast, there were significant differences between plant types for the N and P content of the litter. C content was significantly higher in Hippophae rhamnoides Linn. （417.84 g/kg） than in A. adsurgens and Caragana korshinskii Kom. N content was the highest in A. adsurgens （20.30 g/kg） and the lowest in C. korshinskii, whereas P content was the highest in A. adsurgens （1.57 g/kg） and the lowest in H. rhamnoides. K content was significantly higher in A. adsurgens （6.31 g/kg） than in H. rhamnoides and C. korshinskii. C, N, P, and K content were higher in the leaves than in the litter. The resorption efficiencies of N, P, and K was in the range of 5.17-50.16%, 4.19-6.41%, and 11.27-23.24%, respectively. N resorption was significantly higher in H. rhamnoides than in C. korshinskii and A. adsurgens, P resorption was the highest in A. adsurgens and the lowest in C. korshinskii, and K resorption was the highest in H. rhamnoides （23.24%） and the lowest in C. korshinskii; and （2） Shrubs and herbs had an N/P ratio 〉 16. This finding indicates that the growth of these plants was primarily limited by P. In contrast, macrophanerophytes had an N/P ratio 〈 14, which indicates that growth was primarily limited by N. Combined with C, N, and P content in the soil, leguminous plants should be planted in the early stage of vegetation restoration, followed by shrubs or macrophanerophytes.