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Woody plant encroachment is a global phenomenon, observed in many of the world's drylands. In those with shallow soils overlying karst geology, rock moisture can be an important source of water for woody plants. This source can be particularly important for trees to maintain basic physiological functions during extended droughts, which are becoming more frequent and intense owing to climate change. However, our understanding of rock moisture dynamics in karst drylands undergoing woody plant encroachment is still limited because of the scarcity of direct measurements. In this study, we evaluated soil and rock moisture dynamics at a semiarid site in the Edwards Plateau region of Texas. Our measurements over the course of 3 years showed that in shallow upslope terrain, the dynamic water storage in bedrock was roughly twice that found in soil, whereas in downslope terrain, the dynamic storage was largely restricted to the soil layer. Most of the bedrock storage gains occurred during the first year, after two major storm events of approximately 95 mm, and that storage was gradually depleted during the following 2 years, when precipitation was below average. Importantly, in upslope terrain we found greater rock water storage under woody plants, suggesting that expanding woody vegetation not only has more access to rock moisture, but may also play a role in enhancing bedrock storage capacity. These interconnected abilities can help woody plants survive extended droughts—a factor crucial for understanding their persistence and proliferation in the shallow soils of the Edwards Plateau and similar karst regions.

The emergence of critical zone (CZ) science has provided an integrative platform for investigating plant ecophysiology in the context of landscape evolution, weathering and hydrology. The CZ lies between the top of the vegetation canopy and fresh, chemically unaltered bedrock and plays a pivotal role in sustaining life. We consider what the CZ perspective has recently brought to the study of plant ecophysiology. We specifically highlight novel research demonstrating the importance of the deeper subsurface for plant water and nutrient relations. We also point to knowledge gaps and research opportunities, emphasising, in particular, greater focus on the roles of deep, nonsoil resources and how those resources influence and coevolve with plants as a frontier of plant ecophysiological research.

Depth to bedrock serves as the lower boundary of land surface models, which controls hydrologic and biogeochemical processes. This paper presents a framework for global estimation of depth to bedrock (DTB). Observations were extracted from a global compilation of soil profile data (ca. 1,30,000 locations) and borehole data (ca. 1.6 million locations). Additional pseudo‐observations generated by expert knowledge were added to fill in large sampling gaps. The model training points were then overlaid on a stack of 155 covariates including DEM‐based hydrological and morphological derivatives, lithologic units, MODIS surface reflectance bands and vegetation indices derived from the MODIS land products. Global spatial prediction models were developed using random forest and Gradient Boosting Tree algorithms. The final predictions were generated at the spatial resolution of 250 m as an ensemble prediction of the two independently fitted models. The 10–fold cross‐validation shows that the models explain 59% for absolute DTB and 34% for censored DTB (depths deep than 200 cm are predicted as 200 cm). The model for occurrence of R horizon (bedrock) within 200 cm does a good job. Visual comparisons of predictions in the study areas where more detailed maps of depth to bedrock exist show that there is a general match with spatial patterns from similar local studies. Limitation of the data set and extrapolation in data spare areas should not be ignored in applications. To improve accuracy of spatial prediction, more borehole drilling logs will need to be added to supplement the existing training points in under‐represented areas. Key Points Observations from soil and geological surveys are combined for developing global spatial prediction models of depth to bedrock Machine learning explains 59% of variation in spatial distribution of depth to bedrock for interpolation but much less for extrapolation The framework proposed can be used to gradually improve accuracy by adding more ground observations

Many important insights into the dynamic coupling among climate, erosion, and tectonics in mountain areas have derived from several numerical models of the past few decades which include descriptions of bedrock incision. However, many questions regarding incision processes and morphology of bedrock streams still remain unanswered. A more mechanistically based incision model is needed as a component to study landscape evolution. Major bedrock incision processes include (among other mechanisms) abrasion by bed load, plucking, and macroabrasion (a process of fracturing of the bedrock into pluckable sizes mediated by particle impacts). The purpose of this paper is to develop a physically based model of bedrock incision that includes all three processes mentioned above. To build the model, we start by developing a theory of abrasion, plucking, and macroabrasion mechanisms. We then incorporate hydrology, the evaluation of boundary shear stress, capacity transport, an entrainment relation for pluckable particles, a routing model linking in‐stream sediment and hillslopes, a formulation for alluvial channel coverage, a channel width relation, Hack's law, and Exner equation into the model so that we can simulate the evolution of bedrock channels. The model successfully simulates various features of bed elevation profiles of natural bedrock rivers under a variety of input or boundary conditions. The results also illustrate that knickpoints found in bedrock rivers may be autogenic in addition to being driven by base level fall and lithologic changes. This supports the concept that bedrock incision by knickpoint migration may be an integral part of normal incision processes. The model is expected to improve the current understanding of the linkage among physically meaningful input parameters, the physics of incision process, and morphological changes in bedrock streams.

Background The paper by Korboulewsky and co-authors in this issue of Plant and Soil address some of the central questions of critical zone ecohydrology: how do plants interact with rocks that exclude roots but hold plant-available water? Scope I compare plant water uptake from stony soils and fractured bedrock in the critical zone, suggesting that the two cases may represent endpoints of a continuum along which the proportion of available space for root growth changes. Conclusions Rhizosphere models could be improved and generalized by structuring the layers of the critical zone into volume fractions that can be rooted and fractions from which roots are excluded. I hypothesize that plant-available water capacity of the rooted fraction governs productivity, while plant-available water in the unrooted fraction governs drought resilience.

In the past several decades, field studies have shown that woody plants can access substantial volumes of water from the pores and fractures of bedrock 1 – 3 . If, like soil moisture, bedrock water storage serves as an important source of plant-available water, then conceptual paradigms regarding water and carbon cycling may need to be revised to incorporate bedrock properties and processes 4 – 6 . Here we present a lower-bound estimate of the contribution of bedrock water storage to transpiration across the continental United States using distributed, publicly available datasets. Temporal and spatial patterns of bedrock water use across the continental United States indicate that woody plants extensively access bedrock water for transpiration. Plants across diverse climates and biomes access bedrock water routinely and not just during extreme drought conditions. On an annual basis in California, the volumes of bedrock water transpiration exceed the volumes of water stored in human-made reservoirs, and woody vegetation that accesses bedrock water accounts for over 50% of the aboveground carbon stocks in the state. Our findings indicate that plants commonly access rock moisture, as opposed to groundwater, from bedrock and that, like soil moisture, rock moisture is a critical component of terrestrial water and carbon cycling. Woody plants across the continental United States make extensive use of water stored in bedrock across diverse climates and biomes.

Investigation of underground water becomes very important because it involves human life. The difficulty experienced by the community is the limited potential of underground water, this is due to the uneven distribution of underground water in an area. The purpose of this study is to investigate the presence of groundwater in subsurface rock areas. Groundwater investigations around the bedrock have been successfully carried out using the geoelectric method. The geoelectric survey with Schlumberger configuration was carried out in the investigation area. The results of the study have been observed zones that contain groundwater around rocks with varying thicknesses of 73.25 meters and 119 meters.

Earth's land surface teems with life. Although the distribution of ecosystems is largely explained by temperature and precipitation, vegetation can vary markedly with little variation in climate. Here we explore the role of bedrock in governing the distribution of forest cover across the Sierra Nevada Batholith, California. Our sites span a narrow range of elevations and thus a narrow range in climate. However, land cover varies from Giant Sequoia (Sequoiadendron giganteum), the largest trees on Earth, to vegetation-free swaths that are visible from space. Meanwhile, underlying bedrock spans nearly the entire compositional range of granitic bedrock in the western North American cordillera. We explored connections between lithology and vegetation using measurements of bedrock geochemistry and forest productivity. Tree-canopy cover, a proxy for forest productivity, varies by more than an order of magnitude across our sites, changing abruptly at mapped contacts between plutons and correlating with bedrock concentrations of major and minor elements, including the plant-essential nutrient phosphorus. Nutrient-poor areas that lack vegetation and soil are eroding more than two times slower on average than surrounding, more nutrient-rich, soil-mantled bedrock. This suggests that bedrock geochemistry can influence landscape evolution through an intrinsic limitation on primary productivity. Our results are consistent with widespread bottom-up lithologic control on the distribution and diversity of vegetation in mountainous terrain.

Understanding how groundwater level changes affect the permeability of bedrock aquifer‐aquitard systems is important for groundwater management, yet this relationship remains poorly understood. This study focuses on Tangshan in the northeastern North China Plain, utilizing tidal response analysis to investigate the dynamic interplay between groundwater level trends and permeability variations in bedrock aquifer‐aquitard systems. High‐frequency groundwater level data from two monitoring wells were employed to reveal a significant positive correlation: rising groundwater head leads to increased permeability of the bedrock aquifer‐aquitard system, primarily due to adjustments in groundwater head. This research provides direct evidence that both climate variability and human activities can influence bedrock aquifer‐aquitard permeability through changes in the groundwater head. The findings highlight the importance of integrating models of dynamic permeability induced by hydrological processes into groundwater resource management frameworks and hazard assessments, particularly in regions experiencing groundwater level recovery, such as the North China Plain.

A detailed investigation was conducted on the geological conditions of thin bedrock workfaces under thick backfilled loose bodies in the first panel of the 22-upper coal seam at Shigetai Coal Mine. Utilizing both physical similarity modeling and numerical simulation techniques, the study comprehensively examined the overburden movement patterns and failure characteristics under these conditions. The physical simulation results indicate that as the working face approaches the open-pit slope area, the height of overburden failure gradually increases. When the thin bedrock becomes unstable due to rotation, unconsolidated materials at the slope base flow into the goaf. Subsequently, roof-cutting pressure on the thin bedrock causes simultaneous movement of backfilled loose bodies at different heights, resulting in minor surface settlement. As mining progresses, fracturing alternates periodically between roof-cutting and relief phases, ultimately expanding the surface subsidence zone. The maximum subsidence of the thin bedrock remains less than the mining height of the coal seam. Numerical simulations reveal that when the working face leaves the open-pit slope, the overburden failure height rises rapidly. Upon entering the thin bedrock workface area, advanced fractures develop, and the thin bedrock undergoes full-thickness fracturing in small cycles with intervals of approximately 10 m. The advanced stress fluctuates around the original rock stress, and the movement of backfilled loose bodies quickly reaches the surface. When re-entering the open-pit slope, the development of advanced fractures ceases, and the overburden failure height increases again. The advanced stress gradually rises and stabilizes in the waste dump area. Subsidence in the thin bedrock workface area consistently exceeds that in the open-pit slope area. Maximum subsidence values at different measurement heights are observed within the thin bedrock zone and shift toward the slope base as height increases. When exiting the slope, subsidence in the open-pit area is greater than when entering it. This research elucidates the dynamic fracturing mechanisms and movement patterns of overburden in thin bedrock workfaces beneath thick backfilled loose bodies, providing a theoretical foundation for safe mining in similar geological settings.