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生物土壤结皮广泛分布于许多干旱和半干旱地区,它影响土壤物理过程、水文、侵蚀和养分循环过程,从而影响植物种子萌发与生长发育。该文以新疆准噶尔盆地腹地的古尔班通古特沙漠的生物土壤结皮为研究对象,分析了生物土壤结皮对准噶尔盆地5种荒漠植物(白梭梭(Haloxylon persicum)、蛇麻黄(Ephedra distachya)、角果藜(Ceratocarpus arenaarius)、涩芥(Malcolmia africana)和狭果鹤虱(Lappula semiglabra))的生长及其对元素吸收的影响。结果表明:1)相对于裸沙而言,生物土壤结皮显著促进了荒漠植物的生长速率,并增加了草本植物地上和地下的生物量,但对灌木的生物量无显著影响;2)生物土壤结皮使部分一年生草本植物的开花和结实期提前,这可能有利于荒漠植物在有限的环境资源下快速完成生活史,并繁衍后代;3)生物土壤结皮能够影响荒漠植物对土壤中营养元素的吸收,具体表现在生物土壤结皮显著促进了5种植物对N的吸收,增加了荒漠植物在N贫乏的荒漠生态系统的适应能力,而对P和K的吸收均没有影响。生物土壤结皮对荒漠植物对元素吸收的影响因种而异,对不同的植物有不同的影响。荒漠植物对Mg、Mn和Cu的吸收受生物土壤结皮的影响最小。
Biological soil crusts are widely distributed in many arid and semi-arid regions, affecting soil physical processes, hydrology, erosion and nutrient cycling, and thus affecting plant seed germination and growth. In this paper, the biological soil crusts of the Gurbantunggut Desert in the hinterland of the Junggar Basin in Xinjiang were studied. The effects of biological soil crusts on five desert plants in the Junggar Basin (Haloxylon persicum, Ephedra distachya, Ceratocarpus arenaarius, Malcolmia africana and Lappula semiglabra and their effects on elemental absorption. The results showed that: 1) Biological soil crust significantly promoted the growth rate of desert plants and increased the above and belowground biomass of herbaceous plants, but had no significant effect on the biomass of shrubs; 2) Soil crusting advanced the flowering and fruiting of some annual herbaceous plants, which may facilitate the rapid completion of the life history of desert plants with limited environmental resources and the generation of their offspring. 3) Biological soil crusts could affect the effects of desert plants on soil nutrients Absorption of elements, specifically in biological soil crusts, significantly promoted the uptake of N by five plants and increased the adaptability of desert plants to N-poor desert ecosystems, with no effect on P and K uptake. The impact of biological soil crusts on elemental absorption by desert plants varies from species to species and has different effects on different plants. The absorption of Mg, Mn and Cu by desert plants is the least affected by the biological soil crusts.