Improving models of community change is a fundamental goal in ecology and has renewed importance during global change and increasing human disturbance of the biosphere. Using the Mojave Desert (southwestern United States) as a model system, invaded by nonnative plants and subject to wildfire disturbances, we examined models of resilience, alternative stable states, and convergent‐divergent trajectories for 36 yr of plant community change after 31 wildfires in communities dominated by the native shrubs Larrea tridentata or Coleogyne ramosissima. Perennial species richness on average was fully resilient within 23 yr after disturbance in both community types. Perennial cover was fully resilient within 25 yr in the Larrea community, but recovery was projected to require 52 yr in the Coleogyne community. Species composition shifts were persistent, and in the Coleogyne community, the projected compositional recovery time of 550 yr and increasing resembled a deflected trajectory toward potential alternative states. Disturbed sites contained a perennial species composition of predominately short‐statured forbs, subshrubs, and grasses, contrasting with the larger‐statured shrub and tree structure of undisturbed sites. Auxiliary data sets characterizing species recruitment, annual plants including nonnative grasses, biocrust communities, and soils showed persistent differences between disturbed and undisturbed sites consistent with positive feedbacks potentially contributing to alternative stable states. Resprouting produced limited resilience for the large shrubs L. tridentata and Yucca spp. important to population persistence but did not forestall long‐term reduced abundance of the species. The nonnative annual grass Bromus rubens increased on disturbed sites over time, suggesting persistently abundant nonnative plant fuels and reburn potential. Biocrust cover on disturbed sites was half and species richness a third of amounts on undisturbed sites. Soil nitrogen was 30% greater on disturbed sites and no significant trend was evident for it to decline on even the oldest burns. Disturbed desert plant communities simultaneously supported all three models of resilience, alternative stable states, and convergent‐divergent trajectories among community measures (e.g., species richness, composition), timeframes since disturbance, and spatial resolutions. Accommodating expression within ecosystems of multiple models, including those opposing each other, may help broaden theoretical models of ecosystem change.

中文翻译：

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沙漠野火后的复原力和其他稳定状态

改善社区变化的模式是生态学的基本目标，并且在全球变化和人类对生物圈的日益加剧的干扰下，其重要性得到了重新提高。使用莫哈韦沙漠（美国西南部）作为模型系统，该模型系统受到非本地植物的入侵并受到野火干扰，我们研究了31年野火后36年植物群落变化的复原力，替代稳定状态和会聚-发散轨迹模型。以天然灌木Larrea tridentata或Coleogyne ramosissima为主的群落。两种群落类型均受到干扰后，在23年内，多年生物种的平均丰富度可以完全恢复。拉雷（Larrea）的常年覆盖在25年内完全具有弹性社区，但预计Coleogyne社区需要52年才能恢复。物种组成的变化是持久的，并且在Coleogyne社区，预计550年的成分恢复时间和增加的时间类似于向潜在替代状态的偏转轨迹。受干扰的地点的多年生物种组成主要是矮化的灌木，亚灌木和草，与之相比，未受干扰的地点的灌木和树木结构则占较大地位。辅助数据集以物种招募为特征，一年生植物（包括非原生草，生物结壳群落和土壤）显示出受干扰和未受干扰的地点之间的持续差异，与正反馈相一致，可能有助于形成其他稳定状态。再生对大型灌木L. tridentata和丝兰产生的回弹力有限spp。对于种群持久性很重要，但并不能阻止该物种的长期减少。一年生非本地草布鲁姆斯随着时间的流逝，受干扰地区的植物油增加，表明非本地植物燃料的持续丰富和重燃潜力。受干扰地点的生物外壳覆盖率为一半，不受干扰地点的物种丰富度为三分之一。在受干扰的地区，土壤氮含量增加了30％，即使是最老的烧伤，土壤氮含量也没有明显下降的趋势。受干扰的荒漠植物群落同时支持所有三种复原力模型，替代的稳定状态以及群落测度（例如物种丰富度，组成），扰动以来的时间框架和空间分辨率之间的趋同轨迹。适应多种模式的生态系统内的表达，包括彼此相对的模式，可能有助于拓宽生态系统变化的理论模型。