在荒漠和绿洲过渡带,防风固沙是解决荒漠化和沙漠化问题的重要手段之一。骆驼刺(Alhagi sparsifolia)是沙漠地区常见的一种荒漠深根植物,对防风固沙起到重要作用。当地居民不合理的利用方式导致骆驼刺植被遭受大面积的破坏。本试验以骆驼刺为研究对象,设置对照(control,CK)、春季砍伐(cutting in spring,CS)、春季火烧(burning in spring,BS)、秋季砍伐(cutting in fall,CF)和洪水灌溉(flood water irrigation,FI)5个处理,研究不同干扰方式对骆驼刺生长特征及土壤风蚀的影响。结果表明:在经历13年后(2010—2023年),对照(CK)的株高和冠幅显著高于其他干扰方式,洪水灌溉后的多样性指数、均匀度指数和物种丰富度显著高于其他干扰方式。不同干扰方式下,土壤pH、电导率、全氮、全磷、全钾和速效磷差异不显著。洪水灌溉(FI)后的土壤速效氮显著低于对照(CK),而土壤有机碳和速效钾显著低于春季砍伐(CS)。春季火烧(BS)后的土壤风蚀高度显著低于其他干扰方式。土壤风蚀高度与植株株高和冠幅呈显著正相关。研究结果为更好地保护和合理利用骆驼刺及其他荒漠植被资源提供科学依据。
油田污水生态利用对改良西北地区盐碱化土壤、保持水土和降低污水外排环境影响有重要意义。由于油田污水成分复杂,基于某油田污水组成探究了芨芨草、梭梭、盐地碱蓬和沙棘在盐分、石油烃和化学需氧量(chemical oxygen demand, COD)等主要特征污染物暴露下的耐受程度和生长状况。实验结果表明,不同荒漠植物幼苗在0.3~5.6 g/L盐胁迫下生长未受明显抑制,碱蓬抗盐能力最强;稠油主要通过对根部的毒害作用抑制幼苗生长;作为油田污水COD的重要组分,有机化学药剂抑制植物生长且对碱蓬抑制最显著。不同荒漠植物幼苗表现不同耐受能力,但均可耐受远高于石油烃和COD排放限值的暴露水平,为荒漠地区的油田污水生态利用提供科学依据。The ecological utilization of oilfield wastewater can help improve saline and alkaline soil, conserve soil and water, and reduce environmental impacts of wastewater in northwest China. Based on chemical compositions of an oilfield wastewater, this study investigated effects of salinity, petroleum hydrocarbon and chemical oxygen demand (COD) on seedling growth and survival of desert plants, including Achnatherum splendens, Haloxylon ammodendron, Suaeda salsa and Hippophae rhamnoides. The growth of plant seedlings was less influenced under salinity stress of 0.3~5.6 g/L, and Suaeda salsa exhibited strongest salinity tolerance. The toxicity of petroleum hydrocarbons to roots largely accounted for the inhibition of seedling growth. Suaeda salsa seedlings were most sensitive to exposure of organic chemicals. Results showed these desert plant seedlings can tolerate exposure levels of petroleum hydrocarbons and COD much higher than emission limits, providing scientific support for ecological utilization of oilfield wastewater in desert areas.
