保水剂与木质素结皮相结合对沙化土地植被恢复的调控机理

Regulation Mechanism of Combination of Super Absorbent Polymers and Lignin Crust on Vegetation Restoration in Sandy Grassland

[目的]阐明施用保水剂与木质素结皮结合的恢复措施对沙地植被的调控机制,为荒漠草原沙地植被恢复提供理论依据。[方法]在内蒙古自治区乌拉特荒漠草原设置试验样地。试验处理包括对照和恢复措施(保水剂与木质素结皮结合)两个处理。测定了植物地上生物量、盖度、土壤含水量、土壤团聚体比例、土壤入渗速率、稳渗速率、碱解氮、速效磷和速效钾的含量。[结果]①恢复措施显著提高了植物地上生物量和盖度;②恢复措施提高了水稳性大团聚体比例、入渗速率和稳渗速率,降低了微团聚体的比例,从而显著提高了土壤含水量;③恢复措施显著提高了土壤碱解氮、速效磷和速效钾的含量。[结论]恢复措施提高了土壤含水量和养分含量,提高了沙地植被生产力,从而促进了沙地植被的恢复。

[Objective]The mechanism of underlying vegetation restoration in sandy grassland when combined super absorbent polymers with lignin crust was studied,in order to provide a theoretical basis for the restoration of sandy vegetation in desert grassland.[Methods]The experiment was conducted in Urat Desert grassland in Inner Mongolia Autonomous Region.The two treatments were control and restoration measures(combined application of super absorbent polymers and lignin crust).The above-ground biomass,coverage,soil moisture content,proportion of soil aggregates,soil infiltration rate,stable infiltration rate,alkali-hydrolyzable nitrogen,available phosphorus and available potassium content were assessed.[Results]①Restoration measure significantly increased the aboveground biomass and coverage of plants.②Restoration measure increased the proportion of water-stable macroaggregates,soil infiltration rate,stable infiltration rate,and soil moisture content,but reduced the proportion of microaggregates.③Restoration measure significantly increased the soil alkali-hydrolyzable nitrogen,available phosphorus and available potassium contents.[Conclusion]The restoration measure can increase soil moisture and nutrient contents,improve plant productivity and promote the vegetation restoration in the sandy grassland.