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Motivation: Freshwater ecosystems have been heavily impacted by land‐use changes, but data syntheses on these impacts are still limited. Here, we compiled a global database encompassing 241 studies with species abundance data (from multiple biological groups and geographic locations) across sites with different land‐use categories. This compilation will be useful for addressing questions regarding land‐use change and its impact on freshwater biodiversity. Main Types of Variables Contained: The database includes metadata of each study, sites location, sample methods, sample time, land‐use category and abundance of each taxon. Spatial Location and Grain: The database contains data from across the globe, with 85% of the sites having well‐defined geographical coordinates. Major Taxa and Level of Measurement: The database covers all major freshwater biological groups including algae, macrophytes, zooplankton, macroinvertebrates, fish and amphibians. [ABSTRACT FROM AUTHOR]

Research to inform a sustainable future for southern African mountains as social–ecological systems requires major investment. This is needed to strengthen existing relationships, build new relationships among academia, policy, and practice, and drive a robust research capacity program. This is particularly important in disciplines where there is currently limited capacity for mountain-related research in the region. For many pertinent issues in southern African mountains, the urgent need for foundational research is a reality; without this, it is impossible to build toward multidisciplinary outcomes and to drive transdisciplinary efforts. Keys to strengthening solution-oriented research are improved coordination between actors in similar disciplines (eg water security), strong relationships to achieve maximum synergy instead of competition, and major investment in emerging young researchers. The Afromontane Research Unit is leading the way for southern African mountains. [ABSTRACT FROM AUTHOR]

To exploit the potential of ecological intensification during sunflower cropping, it is crucial to understand the potential synergies between crop management and ecosystem services. We therefore examined the effect of pollination intensification on sunflower yield and productivity under various levels of soil fertilization over two seasons in the eastern Free State, South Africa. We manipulated soil fertility with fertilizer applications and pollination with exclusion bags. We found a synergetic effect between pollination and soil fertilization whereby increasing pollination intensity led to a far higher impact on sunflower yield when the soil had been fertilized. Specifically, the intensification of insect pollination increased seed yield by approximately 0.4 ton/ha on nutrient poor soil and by approximately 1.7 ton/ha on moderately fertilized soil. Our findings suggest that sunflower crops on adequate balanced soil fertility will receive abundant insect pollination and may gain more from both synergies than crops grown in areas with degraded soil fertility. [ABSTRACT FROM AUTHOR]

Gene flow and genetic variation were examined within and among populations of five of the most common spider species in shrublands of the mountainous Golden Gate Highlands National Park (GGHNP), South Africa. These species included three active hunters, Dendryphantes purcelli Peckham & Peckham, 1903 (Salticidae), Pherecydes tuberculatus O.P.-Cambridge, 1883 (Thomisidae) and Philodromus browningi Lawrence, 1952 (Philodromidae), and two web-builders, Neoscona subfusca (C.L. Koch, 1837) (Araneidae) and a Theridion Walckenaer, 1802 species (Theridiidae). A total of 249 spiders (57 D. purcelli, 69 N. subfusca, 34 P. browningi, 56 P. tuberculatus and 33 Theridion sp.) were collected and analysed from six shrubland localities in the park. Analyses of sequence variation of the mitochondrial cytochrome oxidase c subunit I (COI) gene for each species revealed relatively low nucleotide diversity (π < 0.0420) but high genetic diversity (Hd > 0.6500) within populations for all species, except P. tuberculatus. Genetic differentiation was also noted to differ between species, with only P. tuberculatus indicating very large divergence (Fst > 0.2500). These results were reflected by gene flow, with D. purcelli, N. subfusca and the Theridion sp. estimated as experiencing more than one disperser per generation. Overall, highest gene flow was found in the two web-building species, indicating possible high dispersal ability of these spiders in the GGHNP. Additionally, constructed phylogenies indicated possible cryptic speciation occurring in the majority of the investigated species. Our current results indicate that the five investigated spider species were able to maintain gene flow between shrubland populations within the GGHNP to some degree, despite the mountainous landscape. However, further analyses incorporating additional molecular markers are needed to properly determine the extent of genetic diversity and gene flow of these species within the GGHNP. [ABSTRACT FROM AUTHOR]

Globally, Fusarium root rot, which is caused by Fusarium graminearum, reduces wheat (Triticum aestivum L.) yield and quality up to 20%. Colonization of roots by F. graminearum has been recognized, but controlling Fusarium root rot using worm extracts (mucus, vermicompost tea, and vermiwash) has received little attention. We report the antagonistic properties of redworm (Eisenia fetida) extracts against F. graminearum and their effects on wheat seedling growth. Mycelial growth inhibition against the fungus was conducted in quintuplicate using the extracts in vitro. The extracts significantly inhibited mycelial growth of the fungus under in vitro conditions, and there was significant interaction between the infections and extracts for all the parameters measured (root and shoot lengths, root biomass, and disease index). Redworm mucus and 14-d vermiwash produced moderately (26%) to relatively less (16%) antifungal activity, respectively. Vermiwash and augmented vermicompost tea were able to inhibit Fusarium root rot and improve (>58%) the growth of the inoculated seedlings under laboratory conditions. Vermiwash also acted as nutritional supplement, enhancing plant growth. The extracts suppressed F. graminearum and could serve as a potential bio-fungicide in the integrated management of Fusarium root rot in wheat. Longer term experiments under field conditions are needed to validate the findings from the current study. [ABSTRACT FROM AUTHOR]

The present study investigated the use of biochar for the alleviation of the toxic effects of a nanosilver colloidal dispersion and a chloronicotinyl insecticide. The survival and reproduction of the potworm Enchytraeus albidus were assessed after exposure to imidacloprid and silver nanoparticles (AgNPs). E. albidus was exposed to 0, 25, 50, 100, 200, and 400 mg imidacloprid/kg and 0, 5, 25, 125, and 625 mg Ag/kg for 21 days in 10% biochar amended and non-biochar amended OECD artificial soil. In both exposure substrates, the effects of imidacloprid on survival were significant in the two highest treatments (p < 0.01). No biochar effect was observed as survival was statistically similar in both soils after exposure to imidacloprid. In the case of AgNPs, significant mortality was only observed in the highest AgNP treatments in both the amended and non-amended soils (p < 0.05). Nevertheless, statistically greater survival occurred in the biochar-amended treatment (p < 0.05). Reproduction results showed a more pronounced biochar effect with an EC50 = 22.27 mg imidacloprid/kg in the non-amended soil and a higher EC50 = 46.23 mg imidacloprid/kg in the biochar-amended soil. This indicated a 2-fold decrease in imidacloprid toxicity due to biochar amendment. A similar observation was made in the case of AgNPs where a reproduction EC50 = 166.70 mg Ag/kg soil in the non-amended soil increased to an EC50 > 625 mg Ag/kg soil (the highest AgNP treatment) in the amended soil. This indicated at least a 3.7-fold decrease in AgNPs toxicity due to biochar amendment. Although more studies may be needed to optimize the easing effects of biochar on the toxicity of these chemicals, the present results show that biochar could be useful for the alleviation of the toxic effects of imidacloprid and silver nanoparticles in the soil. [ABSTRACT FROM AUTHOR]

Abstract Leaf rust caused by Puccinia triticina is an important disease of wheat worldwide. Different experiments were conducted to determine efficacy of redworm and its extracts against leaf rust on wheat seedlings. The first experiment involved the use of vermicast and artificial soil as planting substrates, and living worms were introduced into soil for four months. This significantly influenced leaf rust severity, with the lowest severity recorded among inoculated plants grown in vermicast (12% severity), followed by soil pulverised with 30 worms (30%) and 20 worms (40%), while control had the highest rust severity (>70%). Second experiment watered the inoculated seedlings with the extracts (vermicast and vermiwash) which resulted into significant lower leaf rust severity of 35% and 53%, respectively while untreated plants had >85% disease severity. Vermicast, which had the highest leaf rust suppression, was further tested, whereby it reduced leaf rust infection up to 30% with increase in seedling shoot and root growth of 21% and 17%, respectively. Redworm enhances resistance to leaf rust infection on inoculated plant via increase in growth that suppresses rust development. [ABSTRACT FROM AUTHOR]

• Non-rehabilitated eroded sites had a higher soil species richness. • Eastern site assemblages differed from western sites of the park. • A single species was identified as a strong indicator of erosion. • Phosphorus levels and soil arthropods can be used as indicators. Soil erosion is a natural process that drives the formation of lowland terrains in mountainous regions. Its role in ecosystem degradation has been strongly debated, due to the significant effect it has on a range of land types. Soil arthropods have been used as indicators of several disturbance types. However, little is known about arthropods in eroded sites in South Africa. The aim of this study was to identify possible indicators of erosion in the Golden Gate Highlands National Park, South Africa, and to determine differences in soil-dwelling arthropod assemblages found in non-rehabilitated and rehabilitated sites over a 24-month period. A total of 5661 soil arthropods were sampled during the study, with the highest species richness recorded in non-rehabilitated eroded sites. A higher number of unique arthropod species were recorded from the non-rehabilitated sites compared to other site types. Overlaps in assemblage structure between site types differed, dependent on site locality. IndVal results, based on species fidelity and specificity in the given habitats, indicated a single strong indicator, the mite Speleorchestes meyerae Theron and Ryke, 1969, for the non-rehabilitated eroded sites. Linear model analyses of site richness with mineralogy identified the significance of phosphorus (in the form of P 2 O 5) in eroded sites. Given these results, soil mineralogy in conjunction with soil arthropod richness of eroded sites could be used to investigate the effect of erosion and form a basis for future study in soil biodiversity and function. [ABSTRACT FROM AUTHOR]