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Ecological systems are severely damaged by the anthropogenic disturbance of mining. Phosphate open‐pit mining fields cover over 200 km2 of the Negev desert, Israel. However, the effects of the ongoing mine site restoration efforts on the plant community have not been studied. Plants and their seed banks have a major role in ecosystem processes and restoration. In this study, we focused on three mining sites, restored in different years, along Zin River valley. We compared the plant community of restored mining plots within these areas to adjacent natural plots. We asked whether plant community germination potential from the soil seed bank differs between the restored plots and the adjacent natural plots within a mining site. We hypothesized that: (1) there is a lack of seed bank in the restored plots; (2) the altered soil composition at the restored plots inhibits germination. We used soil samples collected from the different mining sites and set up greenhouse experiments. One experiment compared natural and restored areas with different soil treatments. In another experiment, we added native seeds to test their germination potential on restored soil. Our results indicate that lack of seed bank is the major limiting factor hindering germination and not the composition of the soil after restoration. Our findings shed light on the constraints of seed bank establishment in post‐mining areas of hyper‐arid regions. We suggest considering active restoration practices to facilitate natural dispersal and improve seed bank establishment. [ABSTRACT FROM AUTHOR]

Biological soil crusts (biocrusts) are key contributors to desert ecosystem functions; therefore, biocrust restoration following mechanical disturbance is imperative. In the Negev Desert hyperarid regions, phosphate mining has been practiced for over 60 years, destroying soil habitats, and fragmenting the landscape. To understand the effects of mining activity on soil health, we previously characterized the biocrust communities in four phosphate mining sites over spatial (post-mining and natural plots) and temporal (2–10 years since restoration) scales. We showed that bacterial abundance, richness, and diversity in natural plots were significantly higher than in post-mining plots, regardless of temporal scale. In this study, we selected one mining site and used DNA stable isotope probing (DNA-SIP) to identify which bacteria grow in post-mining and natural biocrusts. Since biocrust communities activate only after wetting, we incubated the biocrusts with H218O for 96 hours under ambient conditions. We then evaluated the physicochemical soil properties, chlorophyll a concentrations, activation, and functional potential of the biocrusts. The DNA-SIP assay revealed low bacterial activity in both plot types and no significant differences in the proliferated communities' composition when comparing post-mining and natural biocrusts. We further found no significant differences in the microbial functional potential, photosynthetic rates, or soil properties. Our results suggest that growth of hyperarid biocrust bacteria after wetting is minimal. We hypothesize that due to the harsh climatic conditions, during wetting bacteria devote their meager resources to prepare for the coming drought, by focusing on damage repair, and organic compound synthesis and storage rather than on growth. These low growth rates contribute to the sluggish recovery of desert biocrusts following major disturbances such as mining. Therefore, our findings highlight the need for implementing active restoration practices following mining. [ABSTRACT FROM AUTHOR]