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The network of experimental forests and ranges administered by the US Department of Agriculture Forest Service consists of 77 properties that are representative of most forest cover types and many ecological regions in the nation. Established as early as 1908, these sites maintain exceptional, long-term databases on environmental dynamics and biotic responses. Early research at these sites focused on silviculture, ecosystem restoration, and watershed management. Over time, many of the properties have evolved into a functional network of ecological observatories through common large-scale, long-term experiments and other approaches. Collaboration with other institutions and research programs fosters intersite research and common procedures for managing and sharing data. Much current research in this network focuses on global change and interdisciplinary ecosystem studies at local to global scales. With this experience in developing networks and compiling records of environmental history, the experimental forests and ranges network can contribute greatly to formation of new networks of environmental observatories.

Adaptive management of large herbivores requires an understanding of how spatial-temporal fluctuations in forage biomass and quality influence animal performance. Advances in remote sensing have yielded information about the spatial-temporal dynamics of forage biomass, which in turn have informed rangeland management decisions such as stocking rate and paddock selection for free-ranging cattle. However, less is known about the spatial-temporal patterns of diet quality and their influence on large herbivore performance. This is due to infrequent concurrent ground observations of forage conditions with performance (e.g., mass gain), and previously limited satellite data at fine spatial and temporal scales. We combined multi-temporal field observations of diet quality (weekly) and mass gain (monthly) with satellite-derived phenological metrics (pseudo-daily, using data fusion and interpolation) to model daily mass gains of free-ranging yearling cattle in shortgrass steppe. We used this model to predict grazing season (mid-May to October) mass gains, a key management indicator, across 40 different paddocks grazed over a 10-year period (n = 138). We found strong relationships between diet quality and the satellite-derived phenological metrics, especially metrics related to the timing and rate of green-up and senescence. Satellite-derived diet quality estimates were strong predictors of monthly mass gains (R² = 0.68) across a wide range of aboveground net herbaceous production. Season-long predictions of average daily gain and cattle off-mass had mean absolute errors of 8.9% and 2.9%, respectively. The model performed better temporally (across repeated observations in the same paddock) than spatially (across all paddocks within a given year), highlighting the need for accurate vegetation maps and robust field data collection across both space and time. This study demonstrates that free-ranging cattle performance in rangelands is strongly affected by diet quality, which is related to the timing of vegetation green-up and senescence. Senescing vegetation suppressed mass gains, even if adequate forage was available. The satellite-based pseudo-daily approach presented here offers new opportunities for adaptive management of large herbivores, such as identifying within-season triggers to move livestock among paddocks, predicting wildlife herd health, or timing the grazing season to better match earlier spring green-up caused by climate change and plant species invasion.

The aim of the study was to visualize the micromorphology of Amaranthaceous pollen using scanning electron microscopy collected from the Thal Desert. Field collection was conducted from July to September 2021. A total of 14 taxa of the family Amaranthaceae were collected which belong to nine genera. Achyranthes aspera, Aerva javanica, Aerva lanata, Amaranthus graecizans, Amaranthus retroflexus, Amaranthus viridis, Bassia indica, Chenopodium album, Chenopodium ficifolium, Chenopodium murale, Digera muricata, Haloxylon stocksii, Salsola tragus, and Suaeda fruticosa were studied in terms of pollen morphotypes. Pollen were acetolyzed and observed under optical and scanning microscopy. Qualitative and quantitative characters were measured to analyze the pollen to uncover its taxonomic significance. Qualitative characters observed were the shape of pollen in polar and equatorial views; the most frequent shape observed was spheroidal in the polar view, whereas in the equatorial view, prolate spheroidal was the dominant shape. Exine ornamentation is the key characteristic of pollen which is very helpful, and eight different types of ornamentations were observed in collected taxa: smooth sparsely granulate, scabrate-spinulose, microspinulose perforate, microechinate scabrate to metareticulate, granulate, nanospinulate, granulate-spinulose perforate, granulate-perforate echinate, and microechinate perforate. Periporate-type aperture was observed among all taxa. Mesoporia, ektexinous bodies, and tectum features also show variations among Amaranthaceous grains. In quantitative character, A. retroflexus recorded highest in polar view 26.3 μm and the lowest was of C. album 12.2 μm. Highest P/E index ratio was recorded in S. fruticosa (1.12) whereas the lowest for D. muricta (0.94). Exine thickness was highest in S. tragus 2.15 μm and lowest in A. graecizans 0.78 μm. The maximum number of pores was recorded as 32-36 in D. muricata. Artificial taxonomic keys were constructed based on findings that reinforce the importance of the micromorphological ultrastructural diversity of pollen among Amaranthaceous taxa. It was concluded that the descriptions of pollen morphotypes presented greatly contribute to our understanding of desert species identification.

The COVID-19 pandemic has had a devastating impact worldwide, with Iran being one of the hardest-hit countries in the Middle East. Understanding the factors that influence the spread of the virus is crucial for developing effective mitigation strategies. This study aims to investigate the geographical and climatic risk factors associated with COVID-19 incidence in the Kohgiluyeh and Boyer-Ahmad Province of southwest Iran during the 2020−2021 epidemic period. The study involved mapping the residential addresses of 15,585 patients with COVID-19 during 2020–2021. Geographical Information System (GIS) evaluated the effects of geographical and climatic determinants, including temperature, rainfall, humidity, evaporation, elevation, slope, and land cover, on COVID-19 occurrence. The data were analyzed using univariate and multivariate binary logistic regression. In the univariate model, significant climatic factors affecting COVID-19 susceptibility included elevation (p < 0.001, OR=0.617), evaporation (p < 0.001, OR=0.635), dusty days (p < 0.001, OR=1.050), humidity (p = 0.005, OR=1.013), and rainfall (p = 0.032, OR=0.998). Additionally, urban areas (p < 0.001, OR=65), irrigated farms (p < 0.001, OR=5.723), dry farms (p < 0.001, OR=3.101), thin forests (p = 0.009, OR=2.975), and thin rangeland (p = 0.030, OR=2.571) demonstrated the highest impact on the disease distribution. In the multivariate analysis, urban areas (p < 0.001 and OR=47.123), irrigated farms (p < 0.001, OR=4.510), dry farms (p = 0.006, OR=3.002), evaporation (p < 0.001, OR=0.999), and elevation (p < 0.001, OR=0.999) were found to be the main factors related to COVID-19 occurrence. Based on the study results, individuals living in urban areas, irrigated and dry farms, as well as in regions with lower elevation and lower evaporation, have a higher risk of contracting COVID-19.

Background This study evaluated the effects of grazing management practices, topographic position, and land cover types on mineral-associated organic carbon (MAOC) and particulate organic carbon (POC) in a semi-arid rangeland of Kenya. Research was conducted at Mpala Research Centre (controlled grazing) and Ilmotiok Community Group Ranch (continuous grazing) in Laikipia County. A factorial experimental design with a split-plot arrangement was used in this study. Grazing management practices (controlled and continuous grazing) and topographic positions (midslope, foot slope, and bottomland) were assigned to the main plots, while land cover types (bare ground, grass patches, and tree mosaics) were designated as subplots. Soil samples were collected at 10 cm intervals, 0–10 cm, 10–20 cm, and 20–30 cm depth for MAOC and POC analysis. Data analysis was done using R software, where nonparametric tests were done when the assumptions of normality and homogeneity of variance were violated. Results Controlled grazing resulted in higher MAOC (0.361%) and POC (0.683%) compared to continuous grazing (0.352% and 0.548%, respectively), indicating an increase of 2.56% in MAOC and 24.64% in POC under controlled grazing. This can largely be attributed to improved vegetation recovery, especially in midslope areas. The highest MAOC (0.367%) was found in the bottomland, likely due to reduced erosion and improved water retention. The midslope and foot slope positions had lower MAOC means of 0.358% and 0.344%, respectively. Depth analysis showed peak MAOC at 20 cm (0.390%), with controlled grazing resulting in better carbon retention at 30 cm. Similarly, controlled grazing yielded a mean POC of 0.683% versus 0.548% for continuous grazing, with bottomland having the highest POC of 0.754%. A Kruskal‒Wallis tests showed significant differences in MAOC and POC across land cover types (χ² = 42.701, p  < 0.001 for MAOC, and χ² = 83.53, p  < 0.001 for POC), with tree mosaics and bare land contributing most to POC and MAOC, respectively. Conclusions These findings highlight the beneficial role of controlled grazing and diverse land cover in enhancing soil carbon storage. To promote sustainable rangeland management, it is recommended that rangeland managers adopt controlled grazing practices and allow diverse land cover types, such as tree mosaics, to increase carbon sequestration and ecosystem resilience.

Understand how forage quality in semi-arid rangelands is modified by the botanical composition and climatological factors is essential for the appropriate nutritional management of the livestock. This study investigated the influence of the vegetal stratum and season on the bromatological composition of the forage in rangelands from a seasonally dry tropical forest in the Brazilian semi-arid. The experimental design was completely randomized with five replications, and the treatments consisted of two vegetal strata (herbaceous and shrub-arboreal), and two seasons (rainy and dry), in a two-year field trial. There was a significant effect of the season on the crude protein, fiber, hemicellulose, lignin, and soluble carbohydrates (p < 0.05), and the forage showed lower nutritional value during the dry season. Forage dry matter content was greater in the dry season (p < 0.05). There was a pronounced effect of the type of vegetation on the crude protein, fiber, hemicellulose, lignin, total and soluble carbohydrates (p < 0.05), and the herbaceous vegetation was characterized by greater content of fiber compounds and total carbohydrates, while the shrub-arboreal stratum by greater crude protein, soluble carbohydrates, and lignin. The cellulose content was greater in the herbaceous stratum (p < 0.05). The shrub-arboreal strata had greater contents of ether extract (5%), compared to the herbaceous vegetation (1%) (p < 0.05), and it was intensified by the dry season. Despite the mutual influence of the season and the vegetal strata on the bromatological composition of the forage, the type of vegetation of the semi-arid rangelands had a stronger effect in defining forage quality.

Context The > 25,000 km 2 Flint Hills ecoregion in eastern Kansas and northeastern Oklahoma, USA, is an economically and ecologically important area encompassing the largest remaining tallgrass prairie ecosystem in North America. Prescribed fires are used routinely to control invasive woody species and improve forage production for the beef-cattle industry. However, burning releases harmful pollutants that, at times, contribute to air quality problems for communities across a multi-state area. Objectives Establish a modeling framework for synthesizing long-term ecological data in support of Flint Hills tallgrass prairie management goals for identifying how much, where, and when rangeland burning can be conducted to maximize ecological and economic benefits while minimizing regional air quality impacts. Methods We used EPA’s VELMA ecohydrology model to synthesize long-term experimental data at the 35 km 2 Konza Prairie Biological Station (KPBS) describing the effects of climate, fire, grazing, topography, and soil moisture and nutrient dynamics on tallgrass prairie productivity and fuel loads; and to spatially extrapolate that synthesis to estimate grassland productivity and fuel loads across the nearly 1000 times larger Flint Hills ecoregion to support prescribed burning smoke trajectory modeling using the State of Kansas implementation of the U.S. Forest Service BlueSky framework. Results VELMA provided a performance-tested synthesis of KPBS data from field observations and experiments, thereby establishing a tool for regionally simulating the combined effects of climate, fire, grazing, topography, soil moisture, and nutrients on tallgrass prairie productivity and fuel loads. VELMA’s extrapolation of that synthesis allowed difficult-to-quantify fuel loads to be mapped across the Flint Hills to support environmental decision making, such as forecasting when, where, and how prescribed burning will have the least impact on downwind population centers. Conclusions Our regional spatial and temporal extrapolation of VELMA’s KPBS data synthesis posits that the effects of integrated ecohydrological processes operate similarly across tallgrass prairie spatial scales. Based on multi-scale performance tests of the VELMA-BlueSky toolset, our multi-institution team is confident that it can assist stakeholders and decision makers in realistically exploring tallgrass prairie management options for balancing air quality, tallgrass prairie sustainability, and associated economic benefits for the Flint Hills ecoregion and downwind communities.

We investigated experimental warming and simulated grazing (clipping) effects on rangeland quality, as indicated by vegetation production and nutritive quality, in winter-grazed meadows and summer-grazed shrublands on the Tibetan Plateau, a rangeland system experiencing climatic and pastoral land use changes. Warming decreased total aboveground net primary productivity (ANPP) by 40 g.m⁻².yr⁻¹ at the meadow habitats and decreased palatable ANPP (total ANPP minus non-palatable forb ANPP) by 10 g.m⁻².yr⁻¹ at both habitats. The decreased production of the medicinal forb Gentiana straminea and the increased production of the non-palatable forb Stellera chamaejasme with warming also reduced rangeland quality. At the shrubland habitats, warming resulted in less digestible shrubs, whose foliage contains 25% digestible dry matter (DDM), replacing more digestible graminoids, whose foliage contains 60% DDM. This shift from graminoids to shrubs not only results in lower-quality forage, but could also have important consequences for future domestic herd composition. Although warming extended the growing season in non-clipped plots, the reduced rangeland quality due to decreased vegetative production and nutritive quality will likely overwhelm the improved rangeland quality associated with an extended growing season. Grazing maintained or improved rangeland quality by increasing total ANPP by 20-40 g.m⁻².yr⁻¹ with no effect on palatable ANPP. Grazing effects on forage nutritive quality, as measured by foliar nitrogen and carbon content and by shifts in plant group ANPP, resulted in improved forage quality. Grazing extended the growing season at both habitats, and it advanced the growing season at the meadows. Synergistic interactions between warming and grazing were present, such that grazing mediated the warminginduced declines in vegetation production and nutritive quality. Moreover, combined treatment effects were nonadditive, suggesting that we cannot predict the combined effect of global changes and human activities from single-factor studies. Our findings suggest that the rangelands on the Tibetan Plateau, and the pastoralists who depend on them, may be vulnerable to future climate changes. Grazing can mitigate the negative warming effects on rangeland quality. For example, grazing management may be an important tool to keep warming-induced shrub expansion in check. Moreover, flexible and opportunistic grazing management will be required in a warmer future.

Most human‐carnivore conflicts arise from the impact of predation on livestock. In Australian rangelands, considerable resources are allocated to constructing exclusion fences and implementing control measures to manage dingo populations for sustainable livestock enterprise. Assessing the effectiveness of these measures is crucial for justifying the investment. We used a replicated experimental design to examine the effect of landscape‐scale dingo‐proof exclusion fences (‘cell‐fencing’) on activity and population density of dingoes in the Southern Rangelands of Western Australia. We monitored dingo populations for 22–24 months across six study sites nested within a landscape of about 75,000 km2 and defined ‘fence level’ as the number of dingo‐proof fences enclosing each study site. We used camera trap capture rate (number of independent capture events per 100 trap nights) as a metric for dingo activity (including the availability of resources as other potential covariates), estimated dingo density using spatially explicit mark‐resight models, and tested the relationship between capture rate and estimated density of dingoes for each study site. Significant variation in both metrics was observed between sites and across time. Fence level and prey occurrence significantly influenced dingo activity. The annual mean dingo density estimate across study sites was below two dingoes per 100 km2 (i.e., 0.02 dingoes per km2; the maximum value believed to be compatible with small livestock) at only one study site in the first year, but it was higher across all sites during the second year of monitoring. Dingo activity correlated with estimated dingo density at only two sites, suggesting differences in dingo behaviour and detection across the six study sites. This study provides experimental evidence that camera trap capture rate is not a reliable method for assessing variations in the population size of dingoes. These results have implications for monitoring outcomes of dingo control programs across Australia. This study addresses a critical question: How reliable is the activity metric (here we used camera trap capture rate) to assess variations in population size of dingoes across diverse habitats in Australia? Through experimental evidence, we demonstrate that activity metrics can lead to inaccuracies in assessing changes in dingo population size. Our findings highlight the need to assess dingo population size from identified individuals, which is particularly relevant for effective dingo control programs across Australia.

Background Brucellosis is a debilitating zoonotic disease affecting humans and animals. A comprehensive, evidence-based assessment of literature and officially available data on animal and human brucellosis for Kenya are missing. The aim of the current review is to provide frequency estimates of brucellosis in humans, animals and risk factors for human infection, and help to understand the current situation in Kenya. Methods A total of accessible 36 national and international publications on brucellosis from 1916 to 2016 were reviewed to estimate the frequency of brucellosis in humans and animals, and strength of associations between potential risk factors and seropositivity in humans in Kenya. Results The conducted studies revealed only few and fragmented evidence of the disease spatial and temporal distribution in an epidemiological context. Bacteriological evidence revealed the presence of Brucella (B.) abortus and B. melitensis in cattle and human patients, whilst B. suis was isolated from wild rodents only. Similar evidence for Brucella spp infection in small ruminants and other animal species is unavailable. The early and most recent serological studies revealed that animal brucellosis is widespread in all animal production systems. The animal infection pressure in these systems has remained strong due to mixing of large numbers of animals from different geographical regions, movement of livestock in search of pasture, communal sharing of grazing land, and the concentration of animals around water points. Human cases are more likely seen in groups occupationally or domestically exposed to livestock or practicing risky social-cultural activities such as consumption of raw blood and dairy products, and slaughtering of animals within the homesteads. Many brucellosis patients are misdiagnosed and probably mistreated due to lack of reliable laboratory diagnostic support resulting to adverse health outcomes of the patients and routine disease underreporting. We found no studies of disease incidence estimates or disease control efforts. Conclusion The risk for re-emergence and transmission of brucellosis is evident as a result of the co-existence of animal husbandry activities and social-cultural activities that promote brucellosis transmission. Well-designed countrywide, evidence-based, and multidisciplinary studies of brucellosis at the human/livestock/wildlife interface are needed. These could help to generate reliable frequency and potential impact estimates, to identify Brucella reservoirs, and to propose control strategies of proven efficacy.