“肥岛”效应对准噶尔荒漠梭梭种群更新的影响

Shrub “fertile island” provide the favorable microhabitats with respect to soil nutrients, soil moisture, light and heat for plants under canopy in desert with resource stress. Haloxylon ammodendron’s distribution range in the southwestern margin of Junggar basin will be chosen as study area to study the effect of H. ammodendron’s “fertile island” on H. ammodendron’s regeneration through its seed germination and seedling growth. We want to know the effect of “fertile island” on H. ammodendron’s seedling spatial distribution using the method of quadrat survey. We will also sow seeds at interspace between shrubs and in the “fertile island” of H. ammodendron with different ages to study the effect“fertile island” on H.ammodendron’s regeneration and the effect’s change with H.ammodendron’s age. We will collect soil from interspace and “fertile island” of H. ammodendron with different ages to carry out indoor experiments to study soil nutrient accumulation’s contribution to the effect’s change. This study can provide the theoretic foundation for H.ammodendron’s restoration and enhancement and will help explore ecological effects of “fertile island”and its dynamics.

灌木“肥岛”在资源胁迫的荒漠生态系统中为冠下植物的种群更新在土壤养分、水分、光、热等方面提供了良好的微生境。本研究拟以准噶尔盆地西南缘梭梭林保护区为研究区域，通过不同年龄段的成年梭梭冠下的梭梭种子萌发和幼苗生长状况研究梭梭“肥岛”对梭梭自身种群更新的影响及其变化。通过样方调查的方法，掌握自然条件下梭梭冠下“肥岛”对梭梭幼苗的空间分布的影响；采用野外播种实验方法，通过比较林间空地及处于不同年龄阶段的梭梭的 “肥岛”内，梭梭种子萌发和幼苗生长存活的差异，研究“肥岛”对梭梭种群更新的影响及其随梭梭年龄的变化；在林间空地及不同年龄阶段的梭梭 “肥岛”内取土进行室内播种实验，研究“肥岛”内随时间形成的土壤养分聚集梯度在影响变化中的作用。本研究能够为梭梭的生态保育、植被的恢复与重建提供理论依据，并对有助于进一步深入了解荒漠灌木“肥岛”的生态效应及其随灌木年龄的动态变化。