Explore the vast range of titles available.

Bioweathering in arid lands is a complex set of processes comprising a wide variety of organisms, all contributing to soil formation. Weathering starts with outcrop fragmentation by physical forces, later thermal stress and salts produce propagation of cracks that allow colonization by lithobiontic communities. Growth and development of primary colonizers produce pools of C and N available for further establishment of non-vascular plants when moisture is available. Furthermore, plants capable of living in crevices establish interactions with microbial communities and together optimize rock resources (organic or inorganic), enhance nutrient cycling, and accelerate soil development. Cacti and succulents are frequent rock colonizers in hot deserts. These plants exhibit numerous adaptations that enable them to survive in deserts including CAM biochemistry, physiological adaptations, and interactions with their associated microbiome. The associated microbiomes include plant growth-promoting microorganisms that increase essential nutrient supply (N and P) to the plants. We propose a conceptual model of weathering where microbial associates induce higher root exudation of organic acids in succulents. This model has to be experimentally tested; however, it involves several challenges, such as: (a) the difficulty of collecting exudates from the field or emulating experimental conditions similar to nature, and (b) selecting appropriate temporal scales to detect measurable changes since most cacti exhibit remarkably slow growth rates. Therefore, innovative approaches are in order.

Acute malnutrition in children under 5 years is persistent in Eastern Africa's arid and semiarid lands. This study aimed to identify the drivers of acute malnutrition in Turkana and Samburu counties, Kenya. This was a population‐based longitudinal mixed‐methods observational study. Qualitative and quantitative data were collected at Wave 1, but only quantitative data were collected during follow‐up. Participants were a representative sample of children and their primary caregivers from households with children under 3 years at Wave 1. Anthropometric measurements of all children under 5 years in the sampled households were taken at Wave 1 (May to July 2021), and one child under 3 years was randomly selected for follow‐up about every 4 months over 2 years for six data collection waves. The study also collected data on sociodemographics; child feeding practices and morbidity; household water and food insecurity; shocks; coping strategies, social safety nets and economic safeguards; water, sanitation and hygiene; women's decision‐making and food consumption. Qualitative data were collected through community dialogues, focus group discussions, in‐depth interviews, photovoice and key informant interviews with mothers and fathers with children under 5 years, community leaders, county officials and staff of nongovernmental organisations. Data collection is complete and analysis is ongoing. The analysis includes thematic analysis of qualitative data and descriptive and multi‐variable regression analyses of quantitative data. Acute malnutrition in children under 5 years is persistent in Eastern Africa's arid and semi‐arid lands. Nawiri Longitudinal study, which aimed to identify the drivers of acute malnutrition in Turkana and Samburu counties, Kenya, is a population‐based longitudinal mixed‐methods observational study. Participants were a representative sample of children and their primary caregivers from households with children under 3 years at Wave 1. Index children were followed about every 4 months over 2 years for six data collection waves.

Background Aridification is a worldwide serious threat directly affecting agriculture and crop production. In arid and desert areas, it has been found that microbial diversity is huge, built of microorganisms able to cope with the environmental harsh conditions by developing adaptation strategies. Plants growing in arid lands or regions facing prolonged abiotic stresses such as water limitation and salt accumulation have also developed specific physiological and molecular stress responses allowing them to thrive under normally unfavorable conditions. Scope Under such extreme selection pressures, special root-associated bacterial assemblages, endowed with capabilities of plant growth promotion (PGP) and extremophile traits, are selected by the plants. In this review, we provide a general overview on the microbial diversity in arid lands and deserts versus specific microbial assemblages associated with plants. The ecological drivers that shape this diversity, how plant-associated microbiomes are selected, and their biotechnological potential are discussed. Conclusions Selection and recruitment of the plant associated bacterial assemblages is mediated by the combination of the bio-pedo-agroclimatic conditions and the plant species or varieties. Diversity and functional redundancy of these associated PGPR makes them very active in supporting plant improvement, health and resistance to drought, salt and related stresses. Implementing proper biotechnological applications of the arid and desertadapted PGPR constitute the challenge to be raised.

Little is known about the composition, diversity, and geographical distribution of bacterial communities associated with medicinal plants in arid lands. To address this, a collection of 116 endophytic bacteria were isolated from wild populations of the herb Glycyrrhiza uralensis Fisch (licorice) in Xinyuan, Gongliu, and Tekesi of Xinjiang Province, China, and identified based on their 16S rRNA gene sequences. The endophytes were highly diverse, including 20 genera and 35 species. The number of distinct bacterial genera obtained from root tissues was higher (n = 14) compared to stem (n = 9) and leaf (n = 6) tissue. Geographically, the diversity of culturable endophytic genera was higher at the Tekesi (n = 14) and Xinyuan (n = 12) sites than the Gongliu site (n = 4), reflecting the extremely low organic carbon content, high salinity, and low nutrient status of Gongliu soils. The endophytic bacteria exhibited a number of plant growth-promoting activities ex situ, including diazotrophy, phosphate and potassium solubilization, siderophore production, auxin synthesis, and production of hydrolytic enzymes. Twelve endophytes were selected based on their ex situ plant growth-promoting activities for growth chamber assays to test for their ability to promote growth of G. uralensis F. and Triticum aestivum (wheat) plants. Several strains belonging to the genera Bacillus (n = 6) and Achromobacter (n = 1) stimulated total biomass production in both G. uralensis and T. aestivum under low-nutrient conditions. This work is the first report on the isolation and characterization of endophytes associated with G. uralensis F. in arid lands. The results demonstrate the broad diversity of endophytes associated with wild licorice and suggest that some Bacillus strains may be promising candidates for biofertilizers to promote enhanced survival and growth of licorice and other valuable crops in arid environments.

Restoration of degraded arid and semi‐arid lands (ASALs) dryland ecosystems gained traction globally with the enactment of the Bonn Challenge and UN Decade of Restoration. This has been domesticated in Kenya's context by The Forest and Landscape Restoration Implementation Plan (FOLAREP). However, effectively monitoring restored ecosystems is crucial but challenging because of data gaps and technical hurdles, highlighting the need for innovative approaches to assess and restore biodiversity. This study aimed to pilot soil environmental DNA (eDNA) metabarcoding to detect species compositions rapidly, evaluate population structures and abundances, and characterize taxonomic groups. The results from this study serve as a foundational step toward monitoring the impact of water bunds, a restoration approach on biodiversity conservation, in Lower Naibunga Community Conservancy in Laikipia County, Kenya. This study used 16S rDNA and rbCL metabarcoding to assess prokaryotic and plant diversity. Plant growth‐promoting rhizobacteria species attributed to enhancing nutrient availability and improving plant resilience to abiotic stress were prevalent across all six sites: Lorubai (Site 1), Burtany (Site 2), Nkirashi (Site 3), Losopukia (Site 4), Munushoi (Site 5), and Loika (Site 6). Plant species attributed to drought tolerance and rangeland rehabilitation were also identified. The study demonstrates the potential of eDNA metabarcoding as an effective tool for monitoring nature‐based solutions (NbS) interventions to enhance biodiversity and ecosystem restoration in ASALs. The restoration of terrestrial ecosystems in Arid and Semi‐arid Lands (ASALs) has gained momentum through initiatives like the Bonn Challenge and Kenya's Forest and Landscape Restoration Implementation Plan (FOLAREP). This study piloted soil environmental DNA (eDNA) metabarcoding to assess biodiversity in restored areas of Lower Naibunga Community Conservancy, Laikipia County, Kenya, using 16S rDNA and rbCL markers. Results indicated the prevalence of plant growth‐promoting rhizobacteria and drought‐tolerant plant species, demonstrating the potential of eDNA metabarcoding as a monitoring tool for nature‐based restoration interventions.

Climate change and recurring droughts-induced effects on health are becoming an increasingly main global, cultural and public health burden. The heaviest health burden leans on the fragile socio-economic systems among the remote agro-pastoral communities, living in the arid and semi-arid lands (ASALs). Previous studies underlined the indispensability of indigenous knowledge (IK) for resilience-driven disaster risk reduction (DRR) strategies. However, more attention has been drawn towards the necessity of IK in weather forecasts, with less emphasis on its indispensability to alleviate health burden associated with climate change and droughts. We explored the contextual application of IK-based adaptation and related complementarity aspects for culturally relevant and sustainable DRR strategies for the nomadic agro-pastoral communities in Lopur, Turkana, Kenya. Relying on a descriptive qualitative study in phenomenological approach, purposive sampling and focus group discussions with key community influencers, a thematic analysis was conducted for an in-depth understanding and interpretation of data patterns. The contextualised insights revealed the growing vulnerability as a result of the disconnect between modern interventions, IK and the newly adopted environmental degrading coping tactics. Policy-wise, the findings portrayed the necessity for cultural integration and incorporation of indigenous knowledge-based strategies and systems for reinforced information dissemination, accessibility and acceptability for droughts preparedness and response.Contribution: This study underlined the existing room for scientific exploration of the already existing indigenous knowledge-based solutions for food and water insecurity, towards improved resilience for the vulnerable communities experiencing inequitable climate change calamities in the ASALs.

The management of rangelands, including climate change adaptation strategies, is primarily responsible for stimulating livestock productivity, which consequently improves food security. This paper investigates the impact of climate change adaptations on food security among pastoralists in semi-arid parts of Kenya, who have not received due attention to date. Using an endogenous switching regression model, the current study revealed that pastoralists’ food security increased significantly when they employed measures to adapt to climate change. The study results also showed that wealthier households and those with more livestock were more food-secure than comparatively poorer households or those with less livestock. Furthermore, the study uncovered a high prevalence of food security among more educated households. The paper therefore recommends that, in Kenya’s semi-arid lands, where pastoralism is the primary means of livelihood, policies advocating adaptations to climate change should be strengthened. Also fundamental to building pastoralists’ adaptation strategies are the consistent monitoring of climate change, the use of early warning systems, and the communication of pertinent information to farmers—and particularly to pastoralists.

Repeated perturbations, both biotic and abiotic, can lead to fundamental changes in the nature of ecosystems, including changes in state. Sagebrush steppe communities provide important habitat for wildlife and grazing for livestock. Fire is an integral part of these systems, but there is concern that increased ignition frequencies and invasive species are fundamentally altering them. Despite these issues, the majority of studies of fire effects in systems dominated by Artemisia tridentata wyomingensis have focused on the effects of single burns. The Arid Lands Ecology Reserve (ALE), in south-central Washington (USA), was one of the largest contiguous areas of sagebrush steppe habitat in the state until large wildfires burned the majority of it in 2000 and 2007. We analyzed data from permanent vegetation transects established in 1996 and resampled in 2002 and 2009. Our objective was to describe how the fires, and subsequent postfire restoration efforts, affected communities' successional pathways. Plant communities differed in response to repeated fire and restoration; these differences could largely be ascribed to the functional traits of the dominant species. Low-elevation communities, previously dominated by obligate seeders, moved furthest from their initial composition and were dominated by weedy, early-successional species in 2009. Higher-elevation sites with resprouting shrubs, native bunchgrasses, and few invasive species were generally more resilient to the effects of repeated disturbances. Shrub cover has been almost entirely removed from ALE, although there was some recovery where communities were dominated by resprouters. Bromus tectorum dominance was reduced by herbicide application in areas where it was previously abundant, but it increased significantly in untreated areas. Several resprouting species, notably Phlox longifolia and Poa secunda , expanded remarkably following competitive release from shrub canopies and/or abundant B. tectorum . Our results suggest that community dynamics can be understood through a state and transition model with two axes (shrub/grass and native/invasive abundance), although such models also need to account for differences in plant functional traits and disturbance regimes. We use our results to develop a conceptual model that will be validated with further research.

Sand dams are a form of rainwater harvesting, prolific in arid and semi-arid lands. Water is provided partly via handpumps, which, as the only improved method of abstraction from sand dams, are important for drinking water security. Accelerometers and cellular transmitters were fitted to 30 handpumps by the Africa Sand Dam Foundation (ASDF) in 2019 to monitor the use and reliability of the handpumps by recording hourly water volume abstracted. Data from April 2019 to October 2021 for 26 of these sites, alongside qualitative data, were analysed and each handpump’s contribution to year-round water security was explored, focusing on the long dry season when water supply from other sources is compromised. Abstraction was over 20 times higher in the long dry season than in any other season, and at sites with higher salinity, higher livestock use, and larger dam wall area. At 21 wells, abstraction was still being recorded at the end of at least one long dry season; however, high spatial and temporal heterogeneity between pumps and seasons means that not all sand dams deliver reliable water supply year-round. Quantifying the contribution that sand dams make to water security is crucial for understanding their resilience against a changing climate and can aid decision makers when choosing the most appropriate water management technique. Knowledge of temporal and site heterogeneity in abstraction can inform when other water sources need increasing and can help with sand dam design optimisation. Overall, our results indicate the positive contribution that sand dams make to year-round water security through the water that is abstracted through handpumps.

Based on four decades of research by Professor Andrew Goudie, this volume provides a state-of-the-art synthesis of our understanding of desert geomorphology. It presents a truly international perspective, with examples from all over the world. Extensively referenced and illustrated, it covers such topics as the importance of past climatic changes, the variability of different desert environments, rock breakdown, wind erosion and dust storm generation, sand dunes, fluvial and slope forms and processes, the role of the applied geomorphologist in desert development and conservation, and the Earth as an analogue for other planetary bodies. This book is destined to become the classic volume on arid and semi-arid geomorphology for advanced students and researchers in physical geography, geomorphology, Earth science, sedimentology, environmental science and archaeology.