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The study of biodiversity is a fundamental step to develop conservation strategies. Reptile populations are immersed in a global crisis, due to anthropic disturbances. Almost the entire Pampa ecoregion in Argentina was modified for agricultural and livestock activities, the only remnants of mountain native grasslands in Buenos Aires province being the Tandilia and Ventania mountain systems. Ventania reptiles have been exhaustively researched in last years, while Tandilia counts with fewer studies. We presented an actualized reptiles list of the Tandilia Mountain System. We used five data sources to collect presence records: literature, fieldwork, museum collection, citizen science, and a online database. The composition of reptiles from the Tandilia Mountain range includes 26 species in 12 families. Due to the presence of several endemic reptiles, and the representativeness of more than half of the reptiles of Pampa Ecoregion, Tandilia would be useful to determine conservation priority areas to conserve the native grassland and their reptile fauna.

Philodryas agassizii is an endangered snake of shrubland and grasslands well preserved in Argentina, Paraguay, Brazil, and Uruguay. In the southeastern area of its range, this snake was only found associated with highland grassland of the Tandilia and Ventania mountain systems, Argentina. In this work, we described six new records of Philodryas agassizii from the Tandilia Mountain System, which represent four new localities for the species. These records extend the known range of Philodryas agassizii in the Tandilia mountain system, 100 km from the closest previously known site.

Climate changes and associated glacial and interglacial cycles during the Quaternary strongly influenced the evolutionary history of countless number of species. Subtropical highland grasslands (SHG) in southern South America constitute a distinct vegetation type with high diversity and endemism rates. The most recent common ancestor of the genus Petunia (Solanaceae) originated in lowland grasslands, and some lineages secondarily migrated to SHG. Here, we describe the evolutionary history of an SHG species, P. altiplana, distributed throughout a wide area in a river-fragmented landscape. We used plastid and nuclear markers to evaluate the role of the Pelotas River and Quaternary climate cycles over the genetic structure and historical demography of this species based on a phylogeographical approach. We found moderate population expansions during the last 25 kyr, with a more recent (c. 1.6 kya) divergence between two groups of populations from opposite river margins, possibly caused by the expansion of the Araucaria Forest along the river valley, effectively isolating distinct grassland patches. [ABSTRACT FROM AUTHOR]

Byline: M. K. Boakye, I. T. Little, M. D. Panagos and R. Jansen ABSTRACT Fire and grazing have long been used as a grassland management tool in South Africa for [...]

Abstract Genetic polymorphism sharing between closely related and sympatric plant species could result from common ancestry, ancient or recent hybridization. Here we analyzed four Petunia species from the subtropical highland grasslands in southern South America based on nuclear diversity to disentangle the causes of high polymorphism sharing between them. We genotyped microsatellite loci, employed population genetic methods to estimate variability, species limits, and ancient and recent gene flow, and assigned individuals to genetic and taxonomic groups. Finally, we modeled evolutionary processes to determine the impact of Quaternary climate changes on species phylogenetic relationships. Our results indicated that genetic diversity was strongly influenced by expansion and habitat fragmentation during the Quaternary cycles. The extensive polymorphism sharing is mainly due to species’ common ancestry, and we did not discard ancient hybridization. Nowadays, niche differentiation is the primary driver for maintaining genetic and morphological limits between the four analysed Petunia species and there is no recent gene flow between them.

Understanding the botanical composition of herbivores’ diets and their nutritional quality is an important question in the development of sustainable strategies for the management of natural resources. In Chilean highland vicuña-grazed grasslands, there is little information in this regard and, therefore, this study aimed to determine the year-round profile of the diet’s botanical composition and quality. In highland grasslands, on an area of 21.9 ha, continuously grazed for 3.06 VU/ha/year (18°03′ S, 69°13′ W; 4425 m.o.s.l), twelve feces piles were sampled monthly and were analyzed through microhistology, and the nitrogen concentration [NF, OM basis] was determined. The botanical composition, diversity (J) and selectivity index (Ei) of the main species were estimated. Diets were composed of dry–grassland grasses (37.7%), wet–grassland grasses (36.6%), graminoids (14.3%) and forbs (10.2%). The diet diversity ranged from 0.79 (dry–winter) to 0.87 (wet–summer). The main dominant grassland species obtained negative Ei values. The annual mean value of [NF] was estimated as 1.82%, with a higher value in summer months (2.21%), which coincides with the physiological states of higher nutritional demand. The vicuñas behave like generalist ungulates, having a high degree of selectivity towards grass species, which mostly fulfill a nutritional role in subsistence and a functional role in survival, applying foraging strategies that allow them to obtain a better quality diet during the season of greatest nutritional demand.

Twelve stream segments were sampled four times in 1998-1999 (one sampling per season) in the drainage basin of the upper São Francisco River (19º45'-21º25'S, 49º05'-51º30'W), situated in Serra da Canastra National Park, at altitudes ranging from 1,175 to 1,400 m. The macroalgae survey resulted in 30 species, with a predominance of Cyanophyta (12 species = 40%) and Chlorophyta (11 species = 36.5%) and a lower proportion of Rhodophyta (seven species = 23.5%). Two species, Klebsormidium rivulare (Chlorophyta) and Kyliniella latvica (Rhodophyta), were new records for Brazil. Capsosira sp. and Stigonema sp. (Cyanophyta) and the "Chantransia" stage of Batrachospermum (Rhodophyta) were the most widespread macroalgae, occurring in six sampling sites, whereas 11 species were found at only one site. The proportion of macroalgal morphological types were as follows: mats (33%), free filaments (27%), gelatinous filaments (27%), crusts (7%), tufts (3%), and gelatinous colonies (3%). The flora revealed few species in common (4%-8%) with stream macroalgae from other Brazilian regions. The macroalgal communities proved to have species richness values close to the highest values reported in previous studies. The patterns typical for stream macroalgal communities (patchy distribution and dominance of few species) were also found in this basin. However, the stream variables most influential in macroalgal distribution in this study (rocky substratum, low pH, high COD, water color, and current velocity) were essentially the same that best describe the limnological characteristics of this lotic ecosystem. In addition, this combination of variables differed sharply from results of previous studies in other Brazilian stream ecosystems.

Quarrying generates significant changes in the grasslands, by reducing ecological functions, reducing connectivity, impairing biodiversity, and degrading soil. Unlike other forms of destruction such as agriculture or urbanization, mining is characterized by eliminating soil and exposing the bedrock, facilitating groundwater contamination processes. Quarrying in Pampean grassland has been expanding for a century and little is known about the extent and distribution of quarries over the native environment. In this work, we analyze the spatiotemporal variation of quarrying activity on the Highland grassland in the Tandilia mountains of Argentina. Based on Landsat 5, 7, and 8 satellite imagery, from 1996 to 2022, and using QGIS software, we identified the location and extension of quarries, and we analyzed their change through time. Quarries covered 6428 ha, which was originally part of the Pampean grassland. The number of open quarries increased by 129%, from 69 in 1996 to 158 in 2022, and the area used for this activity increased by 172%, with a greater expansion being detected in the last ten years. At least 87 quarries were abandoned in 2022. Quarries are often abandoned without any kind of remediation, leading to further ecosystem deterioration. The current extension of quarrying activity (active and abandoned quarries) reduced the connectivity and a significant area (5.2%) of the Highland grassland of the Tandilia Mountains. Grassland conservation planning should include quarrying as a significant threat, and management actions must be considered to reduce its impact. [ABSTRACT FROM AUTHOR]

Phylogeographic history refers to how species evolve and diversify in response to historical, ecological, and demographic factors. The climate fluctuation during the Pleistocene period marked a crucial time in shaping many species' distribution and genetic structure, particularly those from southern South American grasslands. This work investigated the phylogeographic history of a highland grassland, Petunia altiplana T. Ando & Hashim. (Solanaceae), its diversity, and geographic distribution using a population genomic approach based on RAD-seq data. Our results indicated that, during the Pleistocene, when the grasslands expanded to highlands, the lowland populations of P. altiplana reached the higher open fields, enlarging their geographic distribution. We found that the P. altiplana genetic diversity followed the geographic division into eastern (E) and western (WE) population groups, with a subtle division in the E group regarding the Pelotas River headwater. The results also showed that isolation by distance was the main divergence pattern, with elevation playing a pivotal role in shaping WE and E groups. Our findings indicated that lowland-adapted populations quickly colonized highlands during the late Pleistocene. [ABSTRACT FROM AUTHOR]

Changes in land use are considered the main factor in the degradation of ecosystems, especially in continental aquatic environments. In this study, we evaluated the genotoxicity potential of the environmental matrix using tadpoles from three anuran species as a model, to test whether more genetic damage and changes in oxidative stress biomarkers occur in ponds on farms than in native grasslands. Tadpoles were sampled from ponds in the subtropical highland grassland region of southern Brazil. We quantified DNA damage in tadpoles of Scinax squalirostris, Ololygon aromothyella and Odontophrynus asper using the comet assay and oxidative stress changes using glutathione as a biomarker. Our results demonstrated that the tadpoles of the three anuran species collected in agricultural ponds accumulated greater DNA damage and alterations in biomarkers of oxidative stress when compared with those collected in ponds in the native grassland, corroborating our initial hypothesis. The DNA damage detected in tadpoles from farm ponds suggests that these populations are suffering impacts from environmental contamination, mainly from heavy metals and fertilizers, as indicated by our complementary data. Our results highlight the importance of grassland remnants for the conservation of amphibians in the subtropical region, which are under severe threat due to the replacement of natural areas by agriculture. Moreover, we emphasize the importance of monitoring and quantifying agrochemicals in habitats and organisms to ensure the viability of populations and support adequate management and conservation strategies for the species of pond-breeding anurans in the region of subtropical grasslands in southern Brazil. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: The 26th United Nations Climate Change Conference emphasised the need to modify practices that negatively impact biodiversity and food security in the context of global change. Following Madagascar's drought‐induced famine, our systematic review supports the theory that grasslands of the Malagasy Central Highland that are subjected to human‐lit fires are anthropogenically derived. Furthermore, these overly frequent fires that characterise much of the Malagasy Central Highland grasslands select poorly palatable grasses. Given the reliance on pastoralism as insurance against crop failure in Madagascar, fire‐dependent practices that degrade rangeland emerge as a threat to food security and biodiversity. Education can mitigate against future humanitarian crises. Summary: Food insecurity is greatest in countries where impacts of global change are predicted to be severe. Many, like Madagascar, rely on livestock‐based pastoralism (and consequently palatable rangelands) for insurance against natural disasters and crop failure. It is recognised that derived grasslands can impact climate and biodiversity. Furthermore, the well‐established palatability‐flammability trade‐off predicts that overly‐frequent fires select increasingly unpalatable, fire‐adapted grassland. The drought‐induced Malagasy famine of 2021 highlights the need to identify factors that threaten food security. Given the ubiquitous practice of rangeland preparation through annual, landscape‐scale human‐lit fires, we evaluate whether Malagasy grasslands are derived and then test for fire‐driven selection of increasingly degraded and unpalatable rangelands across Madagascar's largest grassland system, the Malagasy Central Highland (MCH). We conducted a systematic literature review, evaluating for a palatability‐flammability trade‐off, by determining dominant Malagasy grass species, and then applying functional traits, and palatability ratings to these species. Data were extracted using a suite of relevant search terms, and of 1977 studies identified, 145 were directly relevant to the questions posed. Evidence from the review is compelling for much of the Malagasy highland grassland being derived. Furthermore, Malagasy dominant grass species are fire‐adapted with poor forage‐value, suggesting current burning practices negatively impact both biodiversity and pastoralism. Decreasing rangeland palatability caused by human‐lit fires in a society suffering food insecurity emphasises the need to re‐evaluate pastoralist burning practices. Identifying optimal fire frequencies can avert breaching fire‐induced tipping points to rangeland palatability and the humanitarian crises that may follow. [ABSTRACT FROM AUTHOR]

Neotropical temperate grasslands comprise the Pampas ecoregion in Argentina. This region is also the center of agricultural development in Argentina, which has led to a significant simplification and homogenization of the landscape. The Tandilia Mountains, located in the Southeast of the ecoregion, house one of the last remnants of the highland grassland that acts as a refuge for several native species, including both endemic and threatened species. This work aims to present an updated inventory of mammal species that inhabit the highland grassland remnants of the Tandilia Mountains. We used several sources of information to compile the list, including museum collections, citizen science projects (i.e., iNaturalist, EcoRegistros, and Argentinian Network for Monitoring Run Over Fauna), literature, and personal observations. We recorded 40 species of mammals, which include 32 native species and eight exotic species. The richest orders were Rodentia (42.5%), Chiroptera (17.5%), and Carnivora (12.2%). The native mammals found in the Tandilia Mountains represent 44% of the mammal diversity of the Pampas ecoregion, among which there are endemic species of the ecoregion, species whose populations are declining globally, and threatened species. Unfortunately, the presence of protected areas in the system is limited to a few small ones, which highlights the urgency of increasing the number and variety of protected areas. The information presented in this work contributes to the knowledge of biodiversity and the planning of conservation actions for the last remnants of highland grasslands. [ABSTRACT FROM AUTHOR]

Long considered a consequence of anthropogenic agropastoralism, the origin of Madagascar's central highland grassland is hotly disputed. Arguments that ancient endemic grasses formed grassland maintained by extinct grazers and fire have been persuasive. Consequent calls to repeal fire-suppression legislation, burn protected areas, and accept pastoralism as the 'salvation' of endemic grasses mount, even as the International Union for Conservation of Nature (IUCN) declares 98% of lemurs face extinction through fire-driven deforestation. By analysing grass data from contemporary studies, and assessing endemic vertebrate habitat and feeding guilds, we find that although the grassland potentially dates from the Miocene, it is inhospitable to endemic vertebrates and lacks obligate grazers. Endemic grasses are absent from dominant grassland assemblages, yet not from woodland and forest assemblages. There is compelling evidence that humans entered a highland dominated by woodland and forest, and burned it; by 1000 current era (CE), grass pollens eclipsed tree pollens, reminiscent of prevailing fire-induced transformation of African miombo woodland to grassland. Endemic grasses are survivors from vanished woody habitats where grassy patches were likely small and ephemeral, precluding adaptive radiation by endemic vertebrates to form grazing-guilds. Today forests, relic tapia woodland, and outcompeted endemic grasses progressively retreat in a burning grassland dominated by non-endemic, grazing-adapted grasses and cattle. [ABSTRACT FROM AUTHOR]

Andropogon lateralis is a tall and highly plastic tussock-forming grass native from southern South America. It is a frequent component of Campos and Subtropical highland grasslands that often becomes dominant under lax grazing regimes. The aim of this work was to analyze the response of species diversity and forage production of a natural grassland dominated by A. lateralis to a wide range of grazing intensity. We hypothesized that species diversity and forage production would both peak at the intermediate canopy heights determined by grazing regimes of moderate intensity. A grazing experiment was conducted in a highland grassland with mesothermal humid climate at 922 masl (Atlantic Forest biome, Santa Catarina state, Brazil) that comprised 87 species from 20 families but had 50% of its standing biomass accounted by A. lateralis. Four pre-/post-grazing canopy heights—12/7, 20/12, 28/17, and 36/22 cm (measured on A. lateralis)—were arranged in a complete randomized block design with four replications, and intermittently stocked with beef heifers from October 2015 to October 2017. Andropogon lateralis cover decreased (from 75 to 50%), and species richness increased (15–25 species m−2) as canopy height decreased. Grazing intensity did not affect annual forage production (4.2 Mg DM ha−1). This natural grassland dominated by A. lateralis had a high capacity to adjust to grazing regimes of contrasting intensity, maintaining forage production stable over a wide range of canopy heights. However, to prevent losses in floristic diversity, such grassland should not be grazed at canopy heights higher than 28 cm. [ABSTRACT FROM AUTHOR]

The role of the geological uplift and climatic changes during the late Cenozoic on the species diversification of southern African dung beetles is not fully understood. Therefore, we use a divergence-time-estimated phylogeny, macroevolutionary analyses and ecological niche modelling under different climatic scenarios to investigate diversification of the endemic southern African genus, Epirinus. We predict the ancestral range and vegetation type occupied by Epirinus and how late Cenozoic climatic fluctuations and resulting vegetation changes affected speciation and extinction of Epirinus species. Our results suggest that the genus originated in forest with radiation into three geographical centres: (a) north-east escarpment forest and highland grassland; (b) south-east forest; and (c) south-west lowlands to north-east uplands in open vegetation. Reduced speciation rates in the mid-Miocene and increased extinction rates during the drier and cooler Plio-Pleistocene coincide with the replacement of forest by grassland or savanna in southern Africa. The drier climate in southern Africa may have driven extensive contraction of shaded vegetation, forcing an adaptation of forest inhabitants to upland grassland environments, or driving Epirinus species to extinction. Our study supports hypothesis of climatically driven diversification of Epirinus whereas ecological niche modelling across different geological periods suggest that the south-east and, to a lesser extent, the west coast of South Africa as stable areas. [ABSTRACT FROM AUTHOR]

Aim: Palaeoecological data provide an essential long‐term perspective of ecological change and its drivers in oceanic islands. However, analysing the effects of multi‐scalar and potentially co‐occurring disturbances is particularly challenging in dry islands. Here, we aim to identify the ecological consequences of the integrated impacts of a regional drying trend, volcanic eruptions and human mass migrations in a spatially constrained environment—a small, dry oceanic island in Macaronesia. Location: Brava Island, Republic of Cabo Verde. Taxa: Terrestrial vegetation and fungi. Methods: We use palaeoecological analyses applied to a caldera soil profile that dates back to 9700 cal yr BP (calibrated years before the present). Analyses include pollen (vegetation history), non‐pollen palynomorphs (changes in fern and fungal communities), grain‐size distribution, loss‐on‐ignition and geochemistry (sedimentology and erosion regimes), microscopic tephra shards (volcanic ash deposition) and charcoal (fire regime). Results: A regional drying trend after c. 4000 cal yr BP caused increased erosion but had limited immediate impacts on highland grassland vegetation. The expansion of fern‐rich woody scrubland was contemporaneous with significant deposition of volcanic ash and erosion between 1800 and 650 cal yr BP. About 300 cal yr BP, exogenous plants expanded, grazing and fires increased, and there was a decrease of native vegetation cover. Main conclusions: Throughout the Holocene, highland vegetation in Brava was characterized by the presence of open landscapes dominated by herbaceous species (e.g. Poaceae, Forsskaolea), with some presence of woody native taxa (e.g. Ficus, Dodonaea). A regional drying trend was a driver of erosion since the Mid Holocene but did not have an immediate influence on highland vegetation. Tephra deposition is a possible driver of vegetation change. Inter‐island mass migration after volcanic events in Fogo Island c. 1680 CE potentially triggered land use change and intensification, causing a reduction of native vegetation in Brava. [ABSTRACT FROM AUTHOR]

In this paper, the Tourist Area Life Cycle (TALC) model was adapted for application to an urban green space that is not necessarily a tourist destination. Important components of the TALC model, such as carrying capacity, critical life cycle points and a variety of scenarios relevant to urban green spaces that do not primarily have a tourism focus were considered in the development of an adapted model that could be of value in the management of a variety of functions in such spaces. A case study approach was followed, in which the model was applied to the Rietvlei Nature Reserve in Tshwane (South Africa). The functions and benefits of the Rietvlei Nature Reserve include the protection of a portion of the Highland grassland biome with the associated biodiversity, recreation, opportunities for environmental education research, and water provisioning to the City of Tshwane. Qualitative and quantitative data were collected through observation, individual interviews, focus groups and questionnaires, with a total of 558 respondents. The data included primary and secondary sources, and the researchers' own observations. The management of a variety of ecosystem services provided by the conservation area and surrounding urban landscape plays an important role in the life cycle of this urban green space. The value of this study lies in demonstrating that an adaptation of the TALC model can be of value in the sustainable management of the ecological services that urban green spaces provide to urban dwellers. [ABSTRACT FROM AUTHOR]

Abundance, distribution, movement patterns, and habitat selection of a reservoir species influence the dispersal of zoonotic pathogens, and hence, the risk for humans. Movements and microhabitat use of rodent species, and their potential role in the transmission of hantavirus were studied in Otamendi Natural Reserve, Buenos Aires, Argentina. Movement estimators and qualitative characteristics of rodent paths were determined by means of a spool and line device method. Sampling was conducted during November and December 2011, and March, April, June, October, and December 2012. Forty-six Oxymycterus rufus, 41 Akodon azarae, 10 Scapteromys aquaticus and 5 Oligoryzomys flavescens were captured. Movement patterns and distances varied according to sex, habitat type, reproductive season, and body size among species. O. flavescens, reservoir of the etiologic agent of hantavirus pulmonary syndrome in the region, moved short distances, had the most linear paths and did not share paths with other species. A. azarae had an intermediate linearity index, its movements were longer in the highland grassland than in the lowland marsh and the salty grassland, and larger individuals traveled longer distances. O. rufus had the most tortuous paths and the males moved more during the non-breeding season. S. aquaticus movements were associated with habitat type with longer distances traveled in the lowland marsh than in the salty grassland. Hantavirus antibodies were detected in 20% of A. azarae and were not detected in any other species. Seropositive individuals were captured during the breeding season and 85% of them were males. A. azarae moved randomly and shared paths with all the other species, which could promote hantavirus spillover events. [ABSTRACT FROM AUTHOR]

This study aimed to analyze the carbon (C) stock and stabilization of soil organic matter in particulate- and mineral-associated fractions across different land use systems after 32 years of experimentation in the Brazilian Cerrado. The experiment was established in 1991 and was performed in Planaltina-DF. The treatments evaluated included continuous pasture with monoculture grasses; integrated crop–livestock systems under no tillage; continuous cropping under no tillage; minimum tillage; and the preservation of the native Cerrado biome in its original condition. Soil sampling was performed to a depth of 30 cm. Carbon and nitrogen (N) stocks were quantified for the years 2001, 2009, 2013, and 2023, with soil organic matter fractionation performed on samples from 2023. Land use change resulted in significant losses of soil C and N in areas managed with conventional soil preparation practices. Systems that promote plant diversity, such as integrated crop–livestock systems, enhanced soil C and N stocks (72.8 and 5.5 Mg ha−1, respectively) and increased both particulate organic matter and mineral-associated fractions, most of which were in more stabilized forms. Integrated crop–livestock systems are management practices that offer an effective alternative to present methods in terms of combating climate change and supporting ecosystem sustainability. [ABSTRACT FROM AUTHOR]

Internal and external environmental changes have led to changes in the service value of plateau ecosystems. Plateau ecosystems are facing a risk of falling into "recession". Meanwhile, climate change has become an important factor affecting the service value of plateau grassland ecosystems. In this paper, from the perspective of how changes in climate factors inhibit the value of ecosystem services of plateau grasslands, we adopt the equivalent factor method to measure the value of grassland ecosystem services in eight municipal levels in Qinghai Province from 2000 to 2021. We also construct a fixed utility model to test how changes in climate factors affect the value of ecosystem services and use the grass–animal balance as a mediating effect model for the test. The results of the study showed that (1) the increase in temperature and precipitation among the changes in climate factors significantly suppresses the ecosystem service value of grassland in the plateau. (2) The mediation test shows that the grass–livestock balance helped suppress the effects of climate factor changes on the ecological service value of plateau grassland. (3) The heterogeneity test shows that the area containing the Three-River-Source National Park is more resistant to climate factor changes. Climate factor changes have a greater impact on the ecosystem service value of plateau grassland in high altitude areas and have a significant positive effect on sustained low grassland carrying pressure index status. Therefore, in the protection of plateau grassland ecosystems, we should pay attention to the inputs in the ecosystems as well as appropriate grazing. At the same time, this study can provide a reference value for the decision-making with respect to ecological natural resources protection or restoration in plateau grassland under the effects of climate factors. [ABSTRACT FROM AUTHOR]

The authors offer a commentary on the article "Commentary: The role of palaeoecology in reconciling biodiversity conservation, livelihoods and carbon storage in Madagascar" by G. S. Joseph and C. L. Seymour. Topics include the investigation made by the authors on the longevity of open grasslands in the Highlands of Madagascar, reason that binary allocations to forest and/or grassland habitats are problematic, and evidence for the effects of anthropogenic fire according to Seymour and Joseph.

The genus Merodon Meigen (Diptera: Syrphidae) is one of the most species-rich hoverfly genera distributed across the Palaearctic and Afrotropical regions. In the Palaearctic, the genus Merodon boasts 195 described species, while its Afrotropical region pales in comparison, with a mere 17 species documented thus far. As a result of 8 years of fieldwork conducted in the Republic of South Africa, in this paper, we present the description of 11 new species for science with a description of immature stages for 2 species, which increases the diversity of this genus in the Afrotropical region by remarkable 39%. These revelations are based on integrating morphology, molecular analysis (COI gene and 28S rRNA) and geometric morphometry. All described species belong to the Merodon planifacies subgroup, the Merodon desuturinus lineage and, within that, to the Afrotropical Merodon melanocerus group. Additionally, we provide an illustrated key to 15 species belonging to the subgroup, a detailed discussion on relevant taxonomic characters, a morphological diagnosis, a distribution map and clarification of the association between M. capi complex and host plants from the genus Merwilla. [ABSTRACT FROM AUTHOR]

A field experiment was established to quantify the effects of different amounts of rainfall on root growth and dry mass of belowground plant parts in three types of grassland ecosystems. Mountain ( Nardus grassland), highland (wet Cirsium grassland), and lowland grassland (dry Festuca grassland) ecosystems were studied in 2006 and 2007. Roofs constructed above the canopy of grass stands and gravity irrigation systems simulated three climate scenarios: (1) rainfall reduced by 50%, (2) rainfall enhanced by 50%, and (3) the full natural rainfall of the current growing season. Experimentally reduced amounts of precipitation significantly affected both yearly root increments and total root dry mass in the highland grassland. Dry conditions in 2007 resulted in considerable reduction of total belowground dry mass in highland and mountain grasslands. Although not all differences in root biomass of studied grasslands were statistically significantly, some also showed a decrease in root increment and in the amount of belowground dry mass in dry conditions. [ABSTRACT FROM AUTHOR]

Ethiopia has well known paleontological and archaeological sites within the Rift Valley, but relatively little is known of the potential within the surrounding highlands. Here, we present three underexplored sites within and nearby Addis Ababa, Ethiopia's capital city: Fanta, Gemeda, and Koche. These sites were originally mapped in 2008 as part of a rescue project carried out in advance of construction at the Fanta site. As observed in surface contexts and within the modern stream cutbank, Fanta is rich in fossil and archaeological materials. The abundance of hippopotamids at this site (both on the surface and in situ) indicates the presence of a large body of water across the paleolandscape. The site is rich in alcelaphine bovids and equids, and thus likely represents a highland grassland environment. The surface of the site is also rich in artifacts that demonstrate morphologies of the Acheulean technological complex but the relationship of the stone tools to the fauna has yet to be determined. The other sites, Gemeda and Koche are not as rich as Fanta, but may represent other important highland sites. Since discovery, the sites remain underexplored apart from a large-area ground-penetrating radar (GPR) survey at the Fanta site which revealed a vertical succession of reflection packages that have been used to interpret the nature of sedimentary deposits at and away from the exposures. We present the interpretation of previously unpublished GPR data from this survey nearest to the stream cutbank. Finally, all three sites, but especially Fanta, are under threat of destruction from urban development and encroachment, where some of the site has undergone damages and continues to face ongoing destruction. Despite this, the sites offer the opportunity to develop a center of research, education, and tourism with easy access of Ethiopia's growing and dynamic capital city. [ABSTRACT FROM AUTHOR]

Southern Brazil's highland Araucaria Forest-Campos grassland mosaic is an ancient and iconic landscape in the globally important Atlantic Forest biodiversity hotspot. Human land use has inflicted significant losses on the region's natural vegetation since the late 19th Century, but these have not been effectively quantified. This study uses land cover maps and forest survey data to assess how much of the mosaic's natural vegetation remains, the quality of this remnant vegetation, how it has changed since 1985, and the extent to which it is protected. Natural vegetation covers 13.9–37.3 % of the Araucaria Forest-Campos mosaic's core regions and 13.0–38.0 % of the whole area, depending on the dataset. Most remnant areas are degraded and remaining forests have low average integrity. In only minorities of forest plots are the landscape's characteristic Araucaria angustifolia trees still present (23.5 % in the Araucaria Forest region), moderately abundant (11.4 %), or >50 % of the canopy (0.5 %). Major expansions in cropland and forest plantations between 1985 and 2018 drove net/absolute losses of 12.7 %/24.1 % in the mosaic's natural forest and 38.1 %/43.2 % in its natural grasslands. Protected Areas and Indigenous Territories cover 4.6 % of the core mosaic and 6.5 % of the whole region. These conserve important remnant vegetation, though grasslands are under-protected. By analysing and integrating diverse and complementary data sources, we significantly improve on and add nuance to previous estimates of the quantity and quality of Araucaria Forest remnants. This study also provides the first robust, quantitative estimate of remaining highland grassland across southern Brazil. [Display omitted] • Brazil's highland Araucaria Forest-Campos grassland mosaic is highly threatened. • Combining datasets gives key insights into both vegetation coverage and quality. • Natural vegetation covers 13–38 % of the whole mosaic and 14–37 % of its core regions. • Most remnant areas are degraded and remaining forests have low average integrity. • Campos grasslands are less protected and declining even more steeply than forests. [ABSTRACT FROM AUTHOR]

Efforts to identify suitable habitat for wildlife conservation are crucial for safeguarding biodiversity, facilitating management, and promoting sustainable coexistence between wildlife and communities. Our study focuses on identifying potential black rhino (Diceros bicornis) habitat within the Ngorongoro Conservation Area (NCA), Tanzania, across wet and dry seasons. To achieve this, we used remote sensing data with and without field data. We employed a comprehensive approach integrating Sentinel-2 and PlanetScope images, vegetation indices, and human activity data. We employed machine learning recursive feature elimination (RFE) and random forest (RF) algorithms to identify the most relevant features that contribute to habitat suitability prediction. Approximately 36% of the NCA is suitable for black rhinos throughout the year; however, there are seasonal shifts in habitat suitability. Anthropogenic factors increase land degradation and limit habitat suitability, but this depends on the season. This study found a higher influence of human-related factors during the wet season, with suitable habitat covering 53.6% of the NCA. In the dry season, browse availability decreases and rhinos are forced to become less selective of the areas where they move to fulfil their nutritional requirements, with anthropogenic pressures becoming less important. Furthermore, our study identified specific areas within the NCA that consistently offer suitable habitat across wet and dry seasons. These areas, situated between Olmoti and the Crater, exhibit minimal disturbance from human activities, presenting favourable conditions for rhinos. Although the Oldupai Gorge only has small suitable patches, it used to sustain a large population of rhinos in the 1960s. Land cover changes seem to have decreased the suitability of the Gorge. This study highlights the importance of combining field data with remotely sensed data. Remote sensing-based assessments rely on the importance of vegetation covers as a proxy for habitat and often overlook crucial field variables such as shelter or breeding locations. Overall, our study sheds light on the imperative of identifying suitable habitat for black rhinos within the NCA and underscores the urgency of intensified conservation efforts. Our findings underscore the need for adaptive conservation strategies to reverse land degradation and safeguard black rhino populations in this dynamic multiple land-use landscape as environmental and anthropogenic pressures evolve. [ABSTRACT FROM AUTHOR]

Aboveground biomass (AGB) serves as a crucial indicator of the carbon sequestration capacity of coastal wetland ecosystems. Conducting extensive field surveys in coastal wetlands is both time-consuming and labor-intensive. Unmanned aerial vehicles (UAVs) and satellite remote sensing have been widely utilized to estimate regional AGB. However, the mixed pixel effects in satellite remote sensing hinder the precise estimation of AGB, while high-spatial resolution UAVs face challenges in estimating large-scale AGB. To fill this gap, this study proposed an integrated approach for estimating AGB using field sampling, a UAV, and Sentinel-2 satellite data. Firstly, based on multispectral data from the UAV, vegetation indices were computed and matched with field sampling data to develop the Field–UAV AGB estimation model, yielding AGB results at the UAV scale (1 m). Subsequently, these results were upscaled to the Sentinel-2 satellite scale (10 m). Vegetation indices from Sentinel-2 data were calculated and matched to establish the UAV–Satellite AGB model, enabling the estimation of AGB over large regional areas. Our findings revealed the AGB estimation model achieved an R2 value of 0.58 at the UAV scale and 0.74 at the satellite scale, significantly outperforming direct modeling from field data to satellite (R2 = −0.04). The AGB densities of the wetlands in Xieqian Bay, Meishan Bay, and Hangzhou Bay, Zhejiang Province, were 1440.27 g/m2, 1508.65 g/m2, and 1545.11 g/m2, respectively. The total AGB quantities were estimated to be 30,526.08 t, 34,219.97 t, and 296,382.91 t, respectively. This study underscores the potential of integrating UAV and satellite remote sensing for accurately assessing AGB in large coastal wetland regions, providing valuable support for the conservation and management of coastal wetland ecosystems. [ABSTRACT FROM AUTHOR]

The South African grassland system is home to over 3,300 plant species, 15 of the country's 34 endemic mammal species, 12 of the 40 endemic bird species (four of which are globally threatened) and five RAMSAR wetland sites. To assess and address the ecological integrity of farmed grasslands we used process-oriented techniques, including nesting success and field metabolic rates (FMR) of birds, and an adaptation of the multi-taxon biodiversity intactness index (BII) using plant, arthropod and bird diversity data which is a comprehensive tool for assessing ecological integrity using multiple taxonomic groups. Current pastoral management practices have a significant detrimental effect on avian abundance, species richness, nest density and fledgling output. Overall energy turnover and BII values confirm the importance of conserved areas for birds in moist highland grassland systems and support the need for further conservation efforts in grassland systems by both private landowners and reserve managers. Findings based on both avian FMRs and the BII in this study were found to be comparable, lending support to the use of FMR as a rapid assessment technique for assessing ecosystem integrity for future studies of this nature. Scenarios of potential biodiversity improvement with changes in fire management regimes are also presented. [ABSTRACT FROM AUTHOR]

The selection of key soil physical properties (SPPs) for studying the impact of livestock treading is an unexplored research topic, especially in studies that analyze the influence of livestock management on the degradation process. The objective of this work was to demonstrate that the key SPPs for studying the impact of livestock treading depend on the objectives of the research and the environmental characteristics of the study site. This work used discriminant analysis to establish the most significant SPPs among the following: bulk density (BD), total porosity (P), field capacity (FC), infiltration capacity (IC), and aggregate stability (AS). Results showed that (1) IC and BD are the key properties for identifying the areas affected (bare patch) and unaffected (vegetated patch) by livestock treading, (2) none of the SPPs are significant under increasing stocking rates, and (3) BD is the key property for analyzing livestock impact with increasing stocking rate, using soil calcium carbonate content, slope exposure, and grass cover. We concluded that the relationship between physical soil degradation and stocking rate is not linear because it depends on environmental factors; therefore, to establish the key SPPs, it is necessary to take this fact into account. [ABSTRACT FROM AUTHOR]

Leptopelis xenodactylus is a little-known, Endangered species of frog that is thought to be endemic to the KwaZulu-Natal Province of South Africa. In an effort to determine the distribution of this species more accurately, a working species distribution model was created for use in searching for more populations over a period of three breeding seasons. Twenty-one more wetlands containing the frog were discovered and a second species distribution model was created for use in spatial planning applications. Leptopelis xenodactylus occurs primarily in temperate, alluvial hummock wetlands in U-shaped valleys at mid-altitudes in southwestern KwaZulu-Natal. The extent of occurrence and area of occupancy of L. xenodactylus were recalculated including the new records and have increased by 9% and 429%, respectively. The known localities for L. xenodactylus were analysed in relation to the predictions of two downscaled climate change models and a vulnerability framework. Climate change was found to be a potentially significant threat to L. xenodactylus according to the downscaled HadMC2 model and the vulnerability framework, potentially affecting up to 80.5% of the geographic range, but not according to the downscaled GFDL2.1 model and the vulnerability framework which indicated that up to 22% of the geographic range might be affected. The better understanding of the distribution and habitat of L. xenodactylus and of the potential combined impact of climate change and land transformation on the species gained through this study will assist in improving its conservation management. [ABSTRACT FROM AUTHOR]

The taxonomic status of a disjunctive population of Phyllomedusa from southern Brazil was diagnosed using molecular, chromosomal, and morphological approaches, which resulted in the recognition of a new species of the P. hypochondrialis group. Here, we describe P. rustica sp. n. from the Atlantic Forest biome, found in natural highland grassland formations on a plateau in the south of Brazil. Phylogenetic inferences placed P. rustica sp. n. in a subclade that includes P. rhodei + all the highland species of the clade. Chromosomal morphology is conservative, supporting the inference of homologies among the karyotypes of the species of this genus. Phyllomedusa rustica is apparently restricted to its type-locality, and we discuss the potential impact on the strategies applied to the conservation of the natural grassland formations found within the Brazilian Atlantic Forest biome in southern Brazil. We suggest that conservation strategies should be modified to guarantee the preservation of this species. [ABSTRACT FROM AUTHOR]

Resprouting of trees and shrubs in forest-grassland ecotones is a key process to understand the dynamics of these systems under different disturbance regimes. This study integrates resprouting of grassland shrubs and pioneer forest trees ('gullivers'), burned in subtropical lowland grassland and cut in temperate highland grassland of Rio Grande do Sul, Brazil. Per grassland site, 20 individuals each of 1-2 grassland shrub species (Asteraceae) and two forest tree species (Myrsinaceae, Myrtaceae) were tagged, and post-disturbance survival and growth monitored for 1 year at 2-4 month intervals. Differences in resprouting vigour (summed-up basal area of resprouted shoots per pre-disturbance summed-up area of basal stems), and in density and allometry of resprouted shoots (allocation mode) were compared between tree and shrub species by linear mixed effects modelling and multiple comparisons, using the Tukey test. All grassland shrub individuals resprouted and regained 73-142 % (species average) of pre-disturbance basal area within one year, as opposed to 14-24 % in trees. All Myrtaceae 'gullivers' resprouted, but up to two-thirds of Myrsine individuals did not survive disturbance. Tree species tended to produce either many slender or few stout shoots, while shrub species were intermediate between these extremes. Forest trees regained 22-46 % of pre-disturbance height, independent of allocation mode, and grassland shrubs up to 73 %. This suggests that grassland fires allow grassland shrubs but not forest trees to persist and to grow to reproductive size. Differing sprout allocation modes may reflect allometric constraints rather than strategies to outgrow the fire-prone grass matrix. [ABSTRACT FROM AUTHOR]

Grasslands are key to the Earth's system and provide crucial ecosystem services. The degradation of the grassland ecosystem in South Africa is increasing alarmingly, and fire is regarded as one of the major culprits. Globally, anthropogenic climate changes have altered fire regimes in the grassland biome. Integrated fire-risk assessment systems provide an integral approach to fire prevention and mitigate the negative impacts of fire. However, fire risk-assessment is extremely challenging, owing to the myriad of factors that influence fire ignition and behaviour. Most fire danger systems do not consider fire causes; therefore, they are inadequate in validating the estimation of fire danger. Thus, fire danger assessment models should comprise the potential causes of fire. Understanding the key drivers of fire occurrence is key to the sustainable management of South Africa's grassland ecosystems. Therefore, this study explored six statistical and machine learning models—the frequency ratio (FR), weight of evidence (WoE), logistic regression (LR), decision tree (DT), random forest (RF), and support vector machine (SVM) in Google Earth Engine (GEE) to assess fire danger in an Afromontane grassland protected area (PA). The area under the receiver operating characteristic curve results (ROC/AUC) revealed that DT showed the highest precision on model fit and success rate, while the WoE was used to record the highest prediction rate (AUC = 0.74). The WoE model showed that 53% of the study area is susceptible to fire. The land surface temperature (LST) and vegetation condition index (VCI) were the most influential factors. Corresponding analysis suggested that the fire regime of the study area is fuel-dominated. Thus, fire danger management strategies within the Golden Gate Highlands National Park (GGHNP) should include fuel management aiming at correctly weighing the effects of fuel in fire ignition and spread. [ABSTRACT FROM AUTHOR]

Ecosystem multifunctionality (EMF) plays an irreplaceable role in maintaining ecological balance and safeguarding human survival and development. However, a few studies have focused on the changing patterns of multiple ecosystem functions and EMF under different grazing intensities. The study investigated EMF of mountain meadow grasslands on the northern slopes of the Tianshan Mountains in China, through plant community surveys and high-throughput sequencing technology. The study calculated the ecosystem single function and EMF using the single-function method and the mean value method, and explored the effects of no grazing, light grazing, and heavy grazing on the EMF of the grassland. The results showed that the EMF index of grassland ecosystems under grazing conditions ranged from 0.3328 to 0.6018. Compared with no grazing, heavy grazing significantly increased the moisture regulation (MR) function (p < 0.05) and significantly decreased the grass productivity (GP) function and EMF (p < 0.05). While, soil fertility (SF), soil carbon storage (SCS), and nutrient conversion and cycling (NC) functions were not significantly different under the three grazing treatments. The ecosystem functions that contributed most to EMF were GP, SCS, and NC functions under no grazing, light grazing, and heavy grazing conditions, respectively. Under grazing conditions, there were coordination, trade-offs, and neutral relationships between EMF and other ecosystem single functions. The coordinated relationship of EMF and SCS function (r = 0.76, p < 0.05) was strongest, and the trade-offs relationship of EMF and MR function was strongest (r = 0.68, p < 0.05). The results of structural equation modeling indicated that grazing could have a significant effect on EMF directly on the one hand, and indirectly through soil fungal diversity on the other hand. Therefore, grazing plays a key role in maintaining EMF by regulating the function of aboveground and belowground ecosystems mainly through soil fungal diversity. In addition, reasonable reduction of grazing intensity is the most effective management method to maintain ecosystem function. This study elucidated the response of EMF to grazing intensity in mountain grassland, and provided a theoretical basis for the restoration of degraded grassland and the sustainable development of the ecosystem. [ABSTRACT FROM AUTHOR]

Climate change has led to an alarming increase in the frequency and severity of wildfires worldwide. While it is known that amphibians have physiological characteristics that make them highly susceptible to fire, the specific impacts of wildfires on their symbiotic skin bacterial communities (i.e., bacteriomes) and infection by the deadly chytrid fungus, Batrachochytrium dendrobatidis, remain poorly understood. Here, we address this research gap by evaluating the effects of fire on the amphibian skin bacteriome and the subsequent risk of chytridiomycosis. We sampled the skin bacteriome of the Neotropical species Scinax squalirostris and Boana leptolineata in fire and control plots before and after experimental burnings. Fire was linked with a marked increase in bacteriome beta dispersion, a proxy for skin microbial dysbiosis, alongside a trend of increased pathogen loads. By shedding light on the effects of fire on amphibian skin bacteriomes, this study contributes to our broader understanding of the impacts of wildfires on vulnerable vertebrate species. [ABSTRACT FROM AUTHOR]

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Simple Summary: Changes in precipitation patterns can significantly alter biological processes and associated ecosystem functions. This study aimed to investigate the impacts of rainfall intensity and timing on the structure of dung beetle assemblage and dung mass loss rate in a Tibetan alpine meadow. The results revealed that exposure to rainfall within a 2 h timeframe, regardless of rainfall intensity, significantly reduced the rate of dung mass loss. However, this decrease was not attributed to the activity of dung beetles. Earlier rainfall tended to decrease species richness of dung beetles, while heavier rainfall significantly decreased beetle abundance. These findings suggest that changes in precipitation patterns can influence both the assemblage of dung beetles and the rate of dung decomposition, but may also decouple their relationship under a certain circumstance. The variability in local biological processes and ecosystem functions deserves greater attention within a global climate change scenario. Changes in precipitation patterns, including rainfall intensity and rainfall timing, have been extensively demonstrated to impact biological processes and associated ecosystem functions. However, less attention has been paid to the effects of rainfall intensity and rainfall timing on the assembly of detritivore communities and the decomposition rate of detritus such as animal dung. In a grazed alpine meadow on the eastern Qinghai–Tibet Plateau, we conducted a manipulative experiment involving two levels of rainfall intensity (heavy rainfall, 1000 mL/5 min; light rainfall, 100 mL/5 min) and five levels of rainfall timing (0, 2, 4, 24, and 48 h after yak dung deposition). The aim was to determine the effects of rainfall intensity, timing, and their interaction on the assemblage of dung beetles and dung removal rate during the early stage (i.e., 96 h after yak dung deposition) of dung decomposition. Light rainfall significantly increased species richness in the treatment of 48 h after dung pats were deposited. Heavy rainfall significantly decreased beetle abundance in both the 0 h and 48 h treatments while light rainfall had no effect on beetle abundance. Dung mass loss was significant lower in the 2 h treatment compared to other treatments regardless of rainfall intensity. The structural equation model further revealed that the species richness of dung beetles and dung mass loss were significantly affected by rainfall timing but not by rainfall intensity. However, no significant relationships were observed between any variables examined. These findings suggest that changes in precipitation patterns can influence both the structure of dung beetles and the rate of dung decomposition but may also decouple their relationship under a certain circumstance. Therefore, it is crucial to pay greater attention to fully understand local variability between the biological processes and ecosystem functions within a global climate change scenario. [ABSTRACT FROM AUTHOR]