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Fast and accurate quantification of the available pasture biomass is essential to support grazing management decisions in intensively managed fields. The increasing temporal and spatial resolutions offered by the new generation of orbital platforms, such as Planet CubeSat satellites, have improved the capability of monitoring pasture biomass using remotely sensed data. Here, we assessed the feasibility of using spectral and textural information derived from PlanetScope imagery for estimating pasture aboveground biomass (AGB) and canopy height (CH) in intensively managed fields and the potential for enhanced accuracy by applying the extreme gradient boosting (XGBoost) algorithm. Our results demonstrated that the texture measures enhanced AGB and CH estimations compared to the performance obtained using only spectral bands or vegetation indices. The best results were found by employing the XGBoost models based only on texture measures. These models achieved moderately high accuracy to predict pasture AGB and CH, explaining 65% and 89% of AGB (root mean square error (RMSE) = 26.52%) and CH (RMSE = 20.94%) variability, respectively. This study demonstrated the potential of using texture measures to improve the prediction accuracy of AGB and CH models based on high spatiotemporal resolution PlanetScope data in intensively managed mixed pastures.

Abstract There are currently 180 million hectares under pasture in Brazil, and despite the country being one of the largest meat producers, there remain around 64 million hectares that show signs of degradation and contribute to the substantial loss of soil organic carbon (SOC). The aim of this study, therefore, was to derive the factors for SOC stock changes in managed pastures and evaluate the potential for SOC sequestration when converting degraded pastures to well-managed or recovered pastures in Brazil. The study involved 169 paired comparisons, including different types of pasture spread over 14 states in Brazil, and analysed the data in linear mixed-effect models deriving the SOC stock change factors for various soil depths (30 to 100 cm) over 30 years since the change in management. The results showed that for 30 years at a depth of 0–30 cm, compared to native vegetation, nominal pasture (non-degraded grassland, but with no significant management improvements) and improved pasture increased SOC stocks by 15% and 8%, whilst degraded pastures reduced the stocks by 10%. However, the recovery of degraded pastures enhances the SOC by 23%. In terms of the rates of SOC change, pasture degradation leads to losses of 0.25 Mg C ha−1 year−1, whilst nominal or recovered pastures can sequester SOC at rates from 0.25 to 0.54 Mg ha−1 year−1. Overall, it was estimated that the recovery of degraded pastures can sequester up to 3445 Tg of CO2. Nominal management or simple improvement practices can maintain or enhance SOC stocks, helping to mitigate the GHG emissions of livestock in Brazil.

Parallel monitoring of 222 Rn and its short-lived progeny (218 Po and 214 Pb) were carried out from November 2007 to April 2008 close to the top of the Schauinsland mountain, partly covered with forest, in South-West Germany. Samples were aspired from the same location at 2.5 m above ground level. We measured 222 Rn with a dual flow loop, two-filter detector and its short-lived progeny with a one-filter detector. A reference sector for events, facing a steep valley and dominated by pasture, was used to minimize differences between 222 Rn and progeny-derived 222 Rn activity concentrations. In the two major wind sectors covered by forest to a distance between 60 m and 80 m towards the station progeny-derived 222 Rn activity concentration was on average equal to 87% (without precipitation) and 74% (with precipitation) of 222 Rn activity concentration. The observations show that most of the time both detector types follow the same pattern. Still, there is no single disequilibrium factor that could be used to exactly transform short-lived progeny to 222 Rn activity concentration under all meteorological conditions.

Nomadic Pastoralism among the Mongol Herders: Multispecies and Spatial Ethnography in Mongolia and Transbaikalia is based on anthropological research carried out by the author between 2008 and 2016 and addresses the spatial features of nomadic pastoralism among the Mongol herders of Mongolia and Southern Siberia from a cross-comparative perspective. In addition to classical methods of survey, Charlotte Marchina innovatively used GPS recordings to analyze the ways in which pastoralists envision and concretely occupy the landscape, which they share with their animals and invisible entities. The data, represented in abundant and original cartography, provides a better understanding of the mutual adaptations of both herders and animals in the common use of unfenced pastures, not only between different herders but between different species. The author also highlights the herders' adaptive strategies at a time of rapid sociopolitical and environmental changes in this area of the world.

Background The ability to finish livestock on pasture over the summer–autumn period could improve the profitability of red meat enterprises in drought‐prone temperate regions. In south‐eastern Australia, traditional perennial options are limited by poor warm‐season performance (phalaris, Phalaris aquatica L.) and widespread environmental constraints (lucerne, Medicago sativa L.). We aimed to identify perennial species suitable for summer–autumn finishing. Methods We tested pure swards of summer‐active perennial grasses and herbs (20 cultivars across 14 species) in replicated small‐plot experiments at two sites on the Southern Tablelands of New South Wales, Australia. We assessed early persistence, productivity and warm‐season nutritive characteristics over 2–3 years. Results Lucerne and chicory (Cichorium intybus L.) persisted well through drought and produced herbage of high quantity and quality through summer–autumn. Digit grass (Digitaria eriantha Steud.) was highly persistent and productive but nutritive values were generally poor. Cocksfoot (Dactylis glomerata L.), tall fescue (Festuca arundinacea Schreb.), perennial ryegrass (Lolium perenne L.), prairie grass (Bromus willdenowii Kunth.) and plantain (Plantago lanceolata L.) were productive but less persistent through drought, while nutritive values were sometimes inadequate. Conclusions Chicory is a good alternative to lucerne, given its excellent summer–autumn performance, ability to survive droughts and superior acid soil tolerance. If appropriate management resolves issues with persistence and nutritive value, several of the other species could also be used to close the warm‐season feed gap in drought‐prone temperate environments. Pasture quality and quantity limit summer–autumn livestock production in drought‐prone temperate environments. We evaluated summer‐active perennial grasses and herbs over the warm season in south‐eastern Australia. Lucerne and chicory consistently showed high persistence, productivity and nutritive value. Digit grass, cocksfoot, tall fescue, perennial ryegrass, prairie grass and plantain also showed potential.

PURPOSE: Climate change is arguably the biggest environmental challenge facing humanity today. Livestock production systems are a major source of greenhouse gases that contribute to climate change. Nitrous oxide (N₂O) is a potent greenhouse gas with a long-term global warming potential 298 times that of carbon dioxide (CO₂). Nitrate (NO₃ ⁻) leaching from soil causes water contamination, and this is a major environmental issue worldwide. Agriculture is identified as the dominant source for NO₃ ⁻ in surface and ground waters. In grazed grassland systems where animals graze outdoor pastures, most of the N₂O and NO₃ ⁻ are from nitrogen (N) returned to the soil in the excreta of the grazing animal, particularly the urine. This paper reviews published literature on the use of nitrification inhibitors (NI) to treat grazed pasture soils to mitigate NO₃ ⁻ leaching and N₂O emissions. MATERIALS AND METHODS: This paper provides a review on: ammonia oxidisers, including ammonia oxidising bacteria (AOB) and ammonia oxidising archaea (AOA), that are responsible for ammonia oxidation in the urine patch areas of grazed pastures; the effectiveness of NIs, such as dicyandiamide (DCD) and 3,4-dimethylpyrazole phosphate (DMPP), in inhibiting the growth and activity of ammonia oxidisers; the efficacy of DCD and DMPP in reducing NO₃ ⁻ leaching and N₂O emissions in grazed pastures; additional benefits of using NI in grazed pasture, including increased pasture production, decreased cation leaching and decreased NO₃ ⁻ concentrations in plants; and major factors that may affect the efficacy of NIs. RESULTS AND DISCUSSION: Research from a number of laboratory and field studies have conclusively demonstrated that treating grazed pasture soils with a NI, such as DCD, is an effective means of reducing NO₃ ⁻ leaching and N₂O emissions from grazed livestock production systems. Results show that N₂O emissions from animal urine-N can be reduced by an average of 57 % and NO₃ ⁻ leaching from animal urine patches can be reduced by 30 to 50 %. The NI technology has been shown to be effective under a wide range of soil and environmental conditions. The NI technology also provides other benefits, including increased pasture production, reduced cation (Ca²⁺, Mg²⁺ and K⁺) leaching and reduced NO₃ ⁻ concentration in pasture plants which would reduce the risk of NO₃ ⁻ poisoning for the animal. CONCLUSIONS: The use of NIs such as DCD to treat grazed pasture soil is a scientifically sound and practically viable technology that can effectively mitigate NO₃ ⁻ leaching and N₂O emissions in grazed livestock production systems.