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Mineral-associated organic carbon (MAOC) constitutes a major fraction of global soil carbon and is assumed less sensitive to climate than particulate organic carbon (POC) due to protection by minerals. Despite its importance for long-term carbon storage, the response of MAOC to changing climates in drylands, which cover more than 40% of the global land area, remains unexplored. Here we assess topsoil organic carbon fractions across global drylands using a standardized field survey in 326 plots from 25 countries and 6 continents. We find that soil biogeochemistry explained the majority of variation in both MAOC and POC. Both carbon fractions decreased with increases in mean annual temperature and reductions in precipitation, with MAOC responding similarly to POC. Therefore, our results suggest that ongoing climate warming and aridification may result in unforeseen carbon losses across global drylands, and that the protective role of minerals may not dampen these effects.

Earth harbours an extraordinary plant phenotypic diversity1that is at risk from ongoing global changes2,3. However, it remains unknown how increasing aridity and livestock grazing pressure—two major drivers of global change4–6—shape the trait covariation that underlies plant phenotypic diversity1,7. Here we assessed how covariation among 20 chemical and morphological traits responds to aridity and grazing pressure within global drylands. Our analysis involved 133,769 trait measurements spanning 1,347 observations of 301 perennial plant species surveyed across 326 plots from 6 continents. Crossing an aridity threshold of approximately 0.7 (close to the transition between semi-arid and arid zones) led to an unexpected 88% increase in trait diversity. This threshold appeared in the presence of grazers, and moved toward lower aridity levels with increasing grazing pressure. Moreover, 57% of observed trait diversity occurred only in the most arid and grazed drylands, highlighting the phenotypic uniqueness of these extreme environments. Our work indicates that drylands act as a global reservoir of plant phenotypic diversity and challenge the pervasive view that harsh environmental conditions reduce plant trait diversity8–10. They also highlight that many alternative strategies may enable plants to cope with increases in environmental stress induced by climate change and land-use intensification.

Perennial plants create productive and biodiverse hotspots, known as fertile islands, beneath their canopies. These hotspots largely determine the structure and functioning of drylands worldwide. Despite their ubiquity, the factors controlling fertile islands under conditions of contrasting grazing by livestock, the most prevalent land use in drylands, remain virtually unknown. Here we evaluated the relative importance of grazing pressure and herbivore type, climate and plant functional traits on 24 soil physical and chemical attributes that represent proxies of key ecosystem services related to decomposition, soil fertility, and soil and water conservation. To do this, we conducted a standardized global survey of 288 plots at 88 sites in 25 countries worldwide. We show that aridity and plant traits are the major factors associated with the magnitude of plant effects on fertile islands in grazed drylands worldwide. Grazing pressure had little influence on the capacity of plants to support fertile islands. Taller and wider shrubs and grasses supported stronger island effects. Stable and functional soils tended to be linked to species-rich sites with taller plants. Together, our findings dispel the notion that grazing pressure or herbivore type are linked to the formation or intensification of fertile islands in drylands. Rather, our study suggests that changes in aridity, and processes that alter island identity and therefore plant traits, will have marked effects on how perennial plants support and maintain the functioning of drylands in a more arid and grazed world.

The article provides an overview of the wind energy development process, detailing the key considerations for landowners interested in hosting wind farms on their property. Topics include the essential site factors developers look for, such as access to the power grid, land availability, and wind resources; the land requirements for turbines and associated infrastructure; and the multi-year process involved in developing a wind farm, including permits, construction, and long-term operation.

The Namib Sand Sea (NSS) in Namibia is known to preserve a wide variety of Pleistocene-age archaeological sites. However, few Middle Stone Age (MSA) sites in this region have been systematically investigated and basic questions around chronology and technological organization remain open. Here we examine Narabeb, an open air MSA surface site exposed in an interdune pan, ∼30 km into the northern NSS. Narabeb was first documented in the 1970s, and then re-examined in 2021 and 2022 by members of this team. Lithic technological analysis combined with a geomorphological description of the site, palaeoenvironmental interpretation of fine-grain water-lain sediments, and luminescence ages from northern and southern locations on the Narabeb pan provide some of the first understanding of human-environmental interactions and estimates of chronology from the later-Middle and Late Pleistocene in the NSS. In addition, we apply a quantitative approach to aeolian linear dune accumulation and extension to explore possible scenarios for landscape development at this site, in order to better understand the former water course(s) affecting the area. The new chronology suggests this site contained standing water at, or just after, the MIS 7/6 transition, and again at, or just after, the end of MIS 6 into early MIS 5. The timing of greater phases of water availability have some overlap with the speleothem growth record at Rössing Cave, situated ∼90 km north of the NSS (and ∼135 km north of Narabeb). Our results provide the foundation for larger, regional-scale analyses of early human adaptive strategies in this unique environment within Southern Africa.

Reports on a new order of insect called Mantophasmatodea, or Gladiators. Description of the insect which has physical characteristics of a walkingstick, a preying mantis, and a grasshopper; Discovery of insects preserved in amber which resemble recently discovered Gladiators.

Functional structure and diversity of soil free-living nematodes in a desert environment depend on plant gender and sampling site. The objective of this study was to compare the composition, abundance and tropic group of soil free-living nematodes in the upper 0–10 cm soil layer under the male and female Acanthosicyos horridusWelw. ex Hook. f. plants and in the inter-shrub open areas (control) in the Namib Desert, Namibia in April 2015. Soil moisture, organic matter (OM) and pH was also analyzed. Free-living nematodes were extracted from 100 g soil using the Baermann funnel procedure, and total number of nematodes was counted under a microscope. Community composition and diversity of soil free-living nematodes were analyzed using 18S rDNA sequences. Results indicated that a total of 67 groups, including 64 species, 2 genera and 1 family were identified. Feeding behavior of 58 species were identified as follows: 15 bacteria-feeding species, 12 fungi-feeding species, 10 plant-parasite species, 5 omnivorous-predator species, 8 animal-parasite species, 5 invertebrate-parasite species and 3 non-free-living nematodes, known as marine species. Moreover, soil free-living nematodes were found to be affected by sampling locations and plant gender, and community composition and density of these nematodes were strongly influenced by soil OM content. Result confirmed that spatial location and plant cover were main factors influencing the diversity of soil free-living nematodes. Moreover, molecular tools were found to be very useful in defining the richness of soil non-free-living nematodes. In conclusion, the results elucidated the importance of biotic variables in determining the composition and abundance of soil free-living nematodes in the Namib Desert, Namibia.

Panagrolaimus namibiensisn. sp. was recovered and cultured from soils collected under Arthraerua leubnitziae(pencil-bush) in the Namib Desert of Namibia, one of the driest terrestrial habitats on Earth. It is described here based on morphometrics, scanning electron micrographs, light images, line drawings, and molecular data. The new species is distinguished by having a conspicuous posterior deirid, a hook-shaped stegostomal dorsal tooth, and anterior deirids and excretory pore aligned at mid-bulb. It was morphologically compared to eleven well-described species in the genus with which it shared similar labial structure (six distinct rounded lips, and low lip segments separated in pairs), conoid tail, and/or a lateral field with three incisures, including P. labiatus, P. kolymaensis, P. davidi, P. rigidus, and P. superbus. Bayesian phylogenetic analyses using SSU and LSU rDNA each placed P. namibiensisn. sp. within clades of Panagrolaimusspecies, although the two trees resolved its relationship to previously described species differently. Furthermore, our analyses showed the genus is not monophyletic. In a laboratory experiment, P. namibiensisn. sp. survived exposure to 0% relative humidity for 24 h, demonstrating the anhydrobiotic ability of this species that contributes to its survival in the Namib Desert.

Most fog detection from space cannot differentiate fog and low stratus clouds, and cannot estimate fog deposition. This study assessed the feasibility of using spaceborne lidar observations from the Cloud‐Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) in fog detection and estimation. We tested the method in the central Namib Desert, Namibia, where frequent fog events occur and fog observations are available. Results showed the CALIPSO backscatter signal at 532 nm can differentiate low clouds and fog due to its high‐resolution vertical profiles. Backscatter signals during fog events were significantly higher than those during non‐fog periods. The R2between backscatter signals and fog observations was 0.85. Moreover, the backscatter signal was also sensitive to relative humidity variation (R2= 0.66). These results indicate that the CALIPSO data are feasible to estimate fog occurrence and deposition, providing a new perspective for space‐based fog studies. Fog is an important water resource for ecosystem productivity and functions in many dryland regions. Most fog detection from space cannot differentiate fog and low stratus clouds, and cannot estimate fog deposition. The spaceborne lidar measurements from Cloud‐Aerosol Lidar and Infrared Pathfinder Satellite Observation with high‐resolution vertical profiles provide a possibility to differentiate fog and low stratus clouds from space. A significant correlation was shown between spaceborne lidar signals and ground fog observations. Our findings can help investigate fog formation mechanisms as well as improve the capacity and accuracy of satellite‐based fog detection. The first use of spaceborne lidar measurements to retrieve fog depositionThe Cloud‐Aerosol Lidar and Infrared Pathfinder Satellite Observation lidar observations with high‐resolution vertical profiles can differentiate fog and low cloudsThe spaceborne lidar measurements reflect the spatial features of fog and clouds, and can assist to investigate fog formation and identify fog types The first use of spaceborne lidar measurements to retrieve fog deposition The Cloud‐Aerosol Lidar and Infrared Pathfinder Satellite Observation lidar observations with high‐resolution vertical profiles can differentiate fog and low clouds The spaceborne lidar measurements reflect the spatial features of fog and clouds, and can assist to investigate fog formation and identify fog types

AbstractIn this report we review the conservation status of Odonata of southwestern Africa, viz Angola, Botswana, Namibia, Zambia and Zimbabwe. In total, 287 species have been recorded of which three have been previously listed by IUCN. We consider 60 species mainly because of their endemism in the region. The majority of the species have to be categorised as ‘data deficient’ according to IUCN regulations. The most important freshwater habitats in the region are the extensive swamps in the Kalahari basin, such as the Okavango Delta, the Caprivi swamps and the swamps along the courses of the middle Zambezi system, which host a unique odonate community. The most important threats for species in the region include overuse of water, construction of dams in the large rivers and deforestation. We strongly recommend extensive research on the Angolan and Zambian odonate faunas, which appear to be the richest in the regions, although they are poorly investigated.

Co-ordination of 4-methylthiazole-2-dithiocarboxylate methyl ester, I, or benzothiazole-2-dithiocarboxylate methyl ester, II, to [Cr(CO)₅(THF)], [W(CO)₅(THF)] or [Fe(CO)₄(THF)] afforded the new complexes [&z.lb1s;M(CO)₄{S&z.dbd6;C(SCH₃)&z.ub1s;C&z.dbd6;N&z.lb1e;C(CH₃)&z.dbd6;CHS&z.ub1e;}] (M = Cr 1 or W 2), [&z.lb1s;Cr(CO)₄{S&z.dbd6;C(SCH₃)&z.ub1s;C&z.dbd6;N&z.lb1e;C₆H₄S&z.ub1e;-o}] 3, [&z.lb1s;Fe(CO)₃{S&z.dbd6;C(SCH₃)&z.ub1s;C&z.dbd6;N&z.lb1e;C(CH₃)&z.dbd6;CHS&z.ub1e;}] 4 and [&z.lb1s;Fe(CO)₃{S&z.dbd6;C(SCH₃)&z.ub1s;C&z.dbd6;N&z.lb1e;C₆H₄S&z.ub1e;-o}] 5. Single crystal X-ray structure determinations of 1 and 5 revealed co-ordination of the bidentate ligands through the exocyclic thione sulfur and endocyclic imine nitrogen atoms by five-membered chelate ring formation. Compound 5 has a unique trigonal bipyramidal configuration.

Fog is an important water source for many ecosystems, especially in drylands. Most fog‐vegetation studies focus on individual plant scale; the relationship between fog and vegetation function at larger spatial scales remains unclear. This hinders an accurate prediction of climate change impacts on dryland ecosystems. To this end, we examined the effect of fog on vegetation utilizing both optical and microwave remote sensing‐derived vegetation proxies and fog observations from two locations at Gobabeb and Marble Koppie within the fog‐dominated zone of the Namib Desert. Significantly positive relationships were found between fog and vegetation attributes from optical data at both locations. The positive relationship was also observed for microwave data at Gobabeb. Fog can explain about 10%–30% of variability in vegetation proxies. These findings suggested that fog impacts on vegetation can be quantitatively evaluated from space using remote sensing data, opening a new window for research on fog‐vegetation interactions. This study presents the first observed relationships between fog and vegetation function using satellite remote sensing data. Significant correlations were found between fog and satellite‐derived vegetation indices at two study sites within the Namib Desert. These findings suggested that satellite data can be used to assess and quantify the impacts of fog on vegetation at large spatial scales. The positive impact of fog on vegetation is first observed using satellite remote sensing dataFog can explain 10%–30% of variability in vegetation proxiesOptical and microwave remote sensing data showed continuous positive impact of fog on vegetation