喷洒荒漠藻对库布齐沙漠植物群落及土壤养分的影响

Effects of Spraying Desert Algae on Plant Communities and Soil Nutrients in Kubuqi Desert

为揭示荒漠藻对土壤养分改良及植被恢复的影响,在鄂尔多斯高原北缘的半固定沙地进行喷洒荒漠藻试验,调查未喷荒漠藻样地、喷荒漠藻样地内植被与土壤的变化。结果表明:与未喷荒漠藻样地相比,喷荒漠藻对样地灌木层植物组成影响不大,但草本层植物种类明显增加,其天然优势种由1 a生草本植物向多年生草本植物过渡,多年生禾本科植物狼尾草明显增加,1 a生草本植物刺藜、雾冰藜被取代;与未喷荒漠藻样地相比,喷荒漠藻后土壤有机质、全磷含量均增加,第3年土壤有机质含量下降;植被丰富度与土壤全磷呈显著正相关,植被多样性指数与土壤有机质含量成显著正相关,其他植被特征与各土壤指标变化没有显著的相关性;植被丰富度与植被多样性指数呈显著正相关。喷荒漠藻后,明显促进植被恢复与土壤养分改良,加速了自然植被的恢复演替。

In order to reveal the effects of desert algae on soil nutrient improvement and vegetation restoration,an experiment of spraying desert algae was carried out in semi-fixed sandy land on the northern margin of Ordos Plateau to investigate the changes of vegetation and soil nutrients in sample plots with spraying desert algae and without spraying desert algae.The results showed that compared with without spraying desert algae,there was little influence on plant composition of shrub layer after spraying desert algae,but the herbaceous plant species obviously increased.The natural dominant species transited from annual herbs to perennial herbs,perennial gramineae plant Pennisetum alopecuroides increased significantly,annual herbs Dysphania aristata and Bassia dasyphylla were replaced.Soil organic matter and total phosphorus increased after spraying desert algae,but soil organic matter decreased in the third year.There was a significant positive correlation between vegetation richness and soil total phosphorus,meanwhile significant positive was observed between vegetation diversity index and soil organic matter,but there was no significant correlation between other vegetation characteristics and soil index changes.Vegetation richness was significant positively correlated with vegetation diversity index.The application of desert algae significantly promoted the restoration of vegetation and the improvement of soil nutrient,and accelerated the restoration and succession of natural vegetation.