Impacts of the invasive exotic Prosopis juliflora (Sw.) DC on the native flora and soils of the UAE
Impacts of the invasive exotic Prosopis juliflora (Sw.) DC on the native flora and soils of the UAE
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DOI：
10.1007/s11258-006-9188-2
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发表时间：
2007-05-01
期刊：
影响因子：
1.7
通讯作者：
Al-Rawai, Awatif
中科院分区：
文献类型：
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作者：
El-Keblawy, Ali;Al-Rawai, Awatif
在阿拉伯联合酋长国（UAE）的两个地区，评估了外来入侵牧豆草灌木对天然植物群落和土壤化学性状的影响。主观选择了五个地点：沙迦三个，73个看台，拉斯希马两个，37个看台。林分随机分布在每个地点，以覆盖沙迦的密度变化和拉斯希马的大小变化。通过对位于林分中心的一种胡颓子植物群的冠下、边缘和冠外9个样方的调查，研究了胡颓子植物群对一年生和多年生伴生植物的密度、频度、丰富度和均匀度的影响，结果表明，胡颓子对伴生植物群的影响主要取决于林冠的密度和大小。较大的个体和较大的密度对相关植物具有显著较大的负面影响。所有研究的群落属性在核桃林下均显著低于林外。一年生植物比多年生植物受到更多的抑制。一年生植物的数量显着减少的密度和/或频率下P. juliflora冠层显着大于多年生植物的数量。超过50%的相关一年生植物的密度显着抑制下P. juliflora冠。同一树种树冠下的胡黄连幼苗密度大于远离树冠的幼苗密度，表明在田间条件下，胡黄连幼苗很少或没有自我化感作用（自抑制）。胡桃树通过显著降低土壤pH值、增加土壤钾、氮、磷和有机质含量，改善了土壤的某些性状。因此，植物多样性可能会增加后，根除胡黄连。
The effects of the invasive exotic Prosopis juliflora shrubs on the natural plant communities and soil chemical characters were assessed in two regions of the United Arab Emirates (UAE). Five sites were selected subjectively: three in Sharja with 73 stands and two in Ras Al-Khima with 37 stands. Stands were located randomly within each site to cover density variation in Sharja and size variation in Ras Al-Khima. Density, frequency, richness and evenness of the associated annual and perennial species were studied in nine quadrats distributed under, at the margin and outside the canopy of a P. juliflora shrub located in the center of each stand. The results indicated that the effect of P. juliflora on the associated flora depends significantly on the density and size of the canopy. Larger individuals and greater densities have significantly greater negative impacts on the associated plants. All the studied community attributes were significantly lower under P. juliflora canopies than outside. Annuals were inhibited more than perennials. The number of annuals with significant reductions in density and/or frequency under P. juliflora canopies was significantly greater than the number of perennials. Density of more than 50% of the associated annuals was significantly inhibited under P. juliflora canopies. Density of P. juliflora seedlings was greater underneath the canopy of the same species than away from them, indicating little or no self allelopathic effect (auto-inhibition) under field conditions. P. juliflora ameliorated some soil characters, through significant pH reduction and increase in K, N and P and organic matters. Hence, plant diversity might be enhanced following eradication of P. juliflora.