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This study aims to monitor the implications of climate change on savanna ecosystem drought using time series data from the Landsat 8 sensor, spanning from 2013 to 2022. We employed a remote sensing computational approach with the semi-automatic classification plugin (SCP) in the open-source QGIS software. Specifically, we utilized channels from the operational land imager (OLI), including Band 4 Red (0.636-0.673 µm) and Band 5 Near-Infrared (0.851-0.879 µm), as well as Thermal Infrared Sensor (TIRS) channels Band 10 TIRS-1 (10.60-11.19 µm) and Band 11 TIRS-2 (11.50-12.51 µm). These channels were used to calculate the vegetation health index (VHI) using the raster calculator, followed by data reclassification with specific thresholds to compare drought-affected areas. Our findings reveal a significant impact of climate change on savanna ecosystem drought over the decade, with the most extreme conditions observed in 2015 and 2019, where drought coverage reached 42.74% and 26.58%, respectively. Other years exhibited relatively low drought dynamics, affecting less than 3% of the area. This period aligns with the el niño-southern oscillation (ENSO) phenomenon, particularly the transition from El Niño to La Niña, known to cause global weather variations, and significantly influenced by the positive phase of the Indian Ocean dipole (IOD). The novelty of this research lies in two main aspects: firstly, the use of Landsat satellite sensors for this specific region has not been extensively studied before; secondly, the discovered impacts of drought in relation to global climate change phenomena are particularly noteworthy. A limitation of this study is the relatively short investigation period of just one decade, which does not fully capture the long-term impacts of climate change. Future research is recommended to utilize imagery with higher temporal resolution over extended periods to better represent extreme climate events and derive drought patterns over durations exceeding one decade. [ABSTRACT FROM AUTHOR]

Abstract Background Animal movement arises from complex interactions between animals and their heterogeneous environment. To better understand the movement process, it can be divided into behavioural, temporal and spatial components. Although methods exist to address those various components, it remains challenging to integrate them in a single movement analysis. Methods We present an analytic workflow that integrates the behavioural, temporal and spatial components of the movement process and their interactions, which also allows for the assessment of the relative importance of those components. We construct a daily cyclic covariate to represent temporally cyclic movement patterns, such as diel variation in activity, and combine the three components in a multi-modal Hidden Markov Model framework using existing methods and R functions. We compare the trends and statistical fits of models that include or exclude any of the behavioural, spatial and temporal components, and perform variance partitioning on the model predictions that included all components to assess their relative importance to the movement process, both in isolation and in interaction. Results We apply our workflow to a case study on the movements of plains zebra, blue wildebeest and eland antelope in a South African reserve. Behavioural modes impacted movement the most, followed by diel rhythms and then the spatial environment (viz. tree cover and terrain slope). Interactions between the components often explained more of the movement variation than the marginal effect of the spatial environment did on its own. Omitting components from the analysis led either to the inability to detect relationships between input and response variables, resulting in overgeneralisations when drawing conclusions about the movement process, or to detections of questionable relationships that appeared to be spurious. Conclusions Our analytic workflow can be used to integrate the behavioural, temporal and spatial components of the movement process and quantify their relative contributions, thereby preventing incomplete or overly generic ecological interpretations. We demonstrate that understanding the drivers of animal movement, and ultimately the ecological phenomena that emerge from it, critically depends on considering the various components of the movement process, and especially the interactions between them.

Background: Animal movement arises from complex interactions between animals and their heterogeneous environment. To better understand the movement process, it can be divided into behavioural, temporal and spatial components. Although methods exist to address those various components, it remains challenging to integrate them in a single movement analysis. Methods: We present an analytic workflow that integrates the behavioural, temporal and spatial components of the movement process and their interactions, which also allows for the assessment of the relative importance of those components. We construct a daily cyclic covariate to represent temporally cyclic movement patterns, such as diel variation in activity, and combine the three components in a multi-modal Hidden Markov Model framework using existing methods and R functions. We compare the trends and statistical fits of models that include or exclude any of the behavioural, spatial and temporal components, and perform variance partitioning on the model predictions that included all components to assess their relative importance to the movement process, both in isolation and in interaction. Results: We apply our workflow to a case study on the movements of plains zebra, blue wildebeest and eland antelope in a South African reserve. Behavioural modes impacted movement the most, followed by diel rhythms and then the spatial environment (viz. tree cover and terrain slope). Interactions between the components often explained more of the movement variation than the marginal effect of the spatial environment did on its own. Omitting components from the analysis led either to the inability to detect relationships between input and response variables, resulting in overgeneralisations when drawing conclusions about the movement process, or to detections of questionable relationships that appeared to be spurious. Conclusions: Our analytic workflow can be used to integrate the behavioural, temporal and spatial components of the movement process and quantify their relative contributions, thereby preventing incomplete or overly generic ecological interpretations. We demonstrate that understanding the drivers of animal movement, and ultimately the ecological phenomena that emerge from it, critically depends on considering the various components of the movement process, and especially the interactions between them. [ABSTRACT FROM AUTHOR]

Plant transpiration is a key component of the hydrological cycle that moves water from the soil through plants to the atmosphere and is largely determined by environmental conditions. The challenges of highly variable climatic conditions and water scarcity in the semi‐arid savannas of southern Africa drive trees to exhibit different water use strategies.An additional challenge for savanna trees arises from the browsing of large mammals, and its potential impact on transpiration has largely been overlooked.To assess water use strategies and the impact of browsing on transpiration in three common savanna woody species (Colophospermum mopane, Catophractes alexandri, Senegalia mellifera), we conducted an extensive field experiment in a wildlife reserve in Namibia. We established a browsing gradient ranging from 0% to 100% leaf removal to disentangle complex relationships, and we measured sap flow representing whole‐tree transpiration, stomatal conductance as a proxy for leaf level transpiration, and environmental factors including soil moisture, solar radiation, air temperature and air humidity.We discovered a unimodal relationship between browsing intensity and sap flow, consistent across all species, and peaking at low to moderate browsing levels equivalent to approximately 30% leaf removal. This universal pattern is remarkable since we found water use strategies to differ among species: Colophospermum mopane and C. alexandri exhibit a water‐saving behaviour to reduce water loss under unfavourable conditions while S. mellifera demonstrates water‐spending characteristics.The deviation from a negative linear effect of browsing does not meet the functional expectation when browsing is translated into a simple leaf area reduction. Instead, it can be attributed to stomatal adjustments that partially compensate for transpiratory surface loss. We propose that this conceptual mechanism can be generalised to other woody species and various ecosystems. In addition, common transpiration models relying solely on leaf area indices and abiotic factors can be improved by including a non‐linear relationship to reproduce the effect of browsing accurately.Our findings highlight the role of herbivores in shaping the connection between the Earth's spheres and improve our understanding of ecohydrological and vegetation dynamics in Southern African savannas. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

The yield of cowpea varieties is affected by environmental variability. Hence, candidate varieties must be tested for yield stability before release. This study assessed the impacts of genotypes, environments, and their interaction on the performance of elite cowpea lines for key adaptive, grain yield, and associated traits across different locations. A total of 42 elite genotypes were evaluated in five Nigerian environments, representing various savanna ecologies, during the 2021 growing season. The experimental design employed was an alpha lattice arrangement, with each genotype replicated three times. The results revealed significant differences among genotypes, environments, and genotype-by-environment interaction (G × E) for most traits, including days to maturity, 100-seed weight, and grain yield. The genotype and genotype-by-environment interaction (GGE) biplot showed G21 (IT14K-2111-2) and G25 (IT15K-2386-1) as the most stable genotypes across the five environments, G41 (IT11K-61-82) was best adapted to Ibadan and Shika, G5 (245-1) was best adapted to Bagauda and Gumel, and G30 (IT16K-2365-1) was best adapted to Bauchi. G21 (IT14K-2111-2) and G25 (IT15K-2386-1) could be recommended across the five test environments, whereas G41 (IT11K-61-82), G30 (IT16K-2365-1), and G5 (245-1) were specific to the adapted environments. [ABSTRACT FROM AUTHOR]

Allometric equations are the most common way of assessing Aboveground biomass (AGB) but few exist for savanna ecosystems. The need for the accurate estimation of AGB has triggered an increase in the amount of research towards the 3D quantification of tree architecture through Terrestrial Laser Scanning (TLS). Quantitative Structure Models (QSMs) of trees have been described as the most accurate way. However, the accuracy of using QSMs has yet to be established for the savanna. We implemented a non-destructive method based on TLS and QSMs. Leaf-off multi scan TLS point clouds were acquired in 2015 in Kruger National Park, South Africa using a Riegl VZ1000. The 3D data covered 80.8 ha with an average point density of 315.3 points/m2. Individual tree segmentation was applied using the comparative shortest-path algorithm, resulting in 1000 trees. As 31 trees failed to be reconstructed, we reconstructed optimized QSMs for 969 trees and the computed tree volume was converted to AGB using a wood density of 0.9. The TLS-derived AGB was compared with AGB from three allometric equations. The best modelling results had an RMSE of 348.75 kg (mean = 416.4 kg) and a Concordance Correlation Coefficient (CCC) of 0.91. Optimized QSMs and model repetition gave robust estimates as given by the low coefficient of variation (CoV = 19.9% to 27.5%). The limitations of allometric equations can be addressed by the application of QSMs on high-density TLS data. Our study shows that the AGB of savanna vegetation can be modelled using QSMs and TLS point clouds. The results of this study are key in understanding savanna ecology, given its complex and dynamic nature. [ABSTRACT FROM AUTHOR]

In this study, we assessed the co-occurrence influence of Hyptis suaveolens and Urena lobata on native plant species and soil properties in a guinea savanna vegetation in Nigeria. We sampled 120 plots of 10 x 10 m² with 30 plots each in sites invaded by H. suaveolens, U. lobata, mixed site and in sites with none of the species (control). A sparse partial least square discriminant analysis was used to assess the effect of invasive plant treatments on the plant diversity and soil properties, whereas the relationships between the soil properties, plant diversity and invasive species treatments were assessed using the canonical correspondence analysis. The indices of diversity of the control were significantly higher than all the other treatments (p < 0.001) with the mixed site having the lowest. There were significant differences in phosphorus, calcium, aluminium, soil alkalinity and diversity indices among the treatments. The results also indicated that the diversity indices and some soil properties were negatively associated with the mixed site. The negative impacts on the native diversity and change in the soil properties caused by the co-invasion of these two plants are more additive than non-additive. Therefore, priority should be placed on the management of co-invaded sites. [ABSTRACT FROM AUTHOR]

The national food security policy attained through food self-sufficiency is artificial because it does not reflect the actual situation. This policy cannot consolidate various local food resources to serve as the foundation of inclusive national and regional food security. Instead, it tends to rely on exclusive and uniform food security, specifically rice. This contrasts with the geographical reality of Indonesia, which is ecologically endowed with abundant local food resources. This study seeks to explain why local food is neglected in national and regional food security policy frameworks and strategies, although it is acknowledged at the level of ideas and regulations but difficult to implement at the level of practice. This case study was conducted through a series of observations and in-depth interviews with regional policymakers and agricultural communities based on generational differences between those aged 60 and older and those aged 60 and younger. Using the Habitus-Bourdieu analysis, this study discovered that the green revolution policy led to the formation of a collective habitus at the state level, which was then institutionalized in various structural policies of the central and local government, resulting in the formation of an individual habitus at the community level. This habitus that transforms cultivation and food consumption patterns to prioritize rice and marginalizes local foods has created food insecurity, particularly in Savanna ecological regions like Sumba.

Abstract Striga hermonthica is fast spreading in the Nigerian savanna and is predicted to encroach into the rainforest part of the country soon. S. hermonthica seedbanks in savanna soils have continued to rise due to poor agronomic practices by smallholder farmers. Considering differences in soil, climate, and agronomic practices within the savanna endemic agroecology, the severity of the infestation of S. hermonthica has varied from one location to another. Hence, there is a need to model a site-specific management approach for S. hermonthica in Nigeria. This review aims to understand the state-of-the-art management of S. hermonthica in Nigeria’s upland rice fields and further harmonize potential management approaches. Based on studies conducted in Nigeria, reducing S. hermonthica parasitism over a long-term period in the Savanna ecology of Nigeria implies the rotation of upland rice with trap crops, and enhancement of nitrogen fertility in farmers’ fields, combined with the use of seed-treated resistant or tolerant cultivars. In practical terms, farmer’s-research engagement in the long term is pertinent to reduce the severity of S. hermonthica in threatened areas. [ABSTRACT FROM AUTHOR]

Savanna landscapes are shaped by the interactions of disturbances with land use goals. Elephant hunting in a site in Botswana, and its consequences for wildlife, people, and landscapes, are described and discussed in order to make broader generalizations about the dynamics of savanna landscapes. Change comes from alterations in tree-grass interactions, fire regimes, predator-prey relations, livestock raising, and conservation goals. Some of these implications are specific to African landscapes, but others may be apt in global contexts. [ABSTRACT FROM AUTHOR]

Less than half of the original two million km2 of the Brazilian Savanna natural vegetation, called the Cerrado Biome, remains standing. Given its climate and socio-biodiversity importance, more effective public policies are needed to protect the remaining natural areas. In this paper, we present the methodology and results of the DETER Cerrado, an early warning deforestation system within the Cerrado region. The findings support that DETER is effective in detecting a wider range of deforestation patch sizes, from the larger patches, heavily associated with agricultural expansion, to the smaller areas (>1 ha <10 ha). Nevertheless, 80% of the deforestation is concentrated in the 10-km radius zone from the DETER Alerts. This area was later detected by the Cerrado Deforestation Monitoring Project (PRODES), the system that accounts for the annual deforestation rate assessment, which highlights the capability of the DETER system to provide support to the surveillance of deforestation in the Cerrado. [ABSTRACT FROM AUTHOR]

The longleaf pine (Pinus palustris Mill.) and related ecosystem is an icon of the southeastern United States (US). Once covering an estimated 37 million ha from Texas to Florida to Virginia, the near-extirpation of, and subsequent restoration efforts for, the species has been well-documented over the past ca. 100 years. Although longleaf pine is one of the longest-lived tree species in the southeastern US—with documented ages of over 400 years—its use has not been reviewed in the field of dendrochronology. In this paper, we review the utility of longleaf pine tree-ring data within the applications of four primary, topical research areas: climatology and paleoclimate reconstruction, fire history, ecology, and archeology/cultural studies. Further, we highlight knowledge gaps in these topical areas, for which we introduce the Longleaf Tree-Ring Network (LTRN). The overarching purpose of the LTRN is to coalesce partners and data to expand the scientific use of longleaf pine tree-ring data across the southeastern US. As a first example of LTRN analytics, we show that the development of seasonwood chronologies (earlywood width, latewood width, and total width) enhances the utility of longleaf pine tree-ring data, indicating the value of these seasonwood metrics for future studies. We find that at 21 sites distributed across the species' range, latewood width chronologies outperform both their earlywood and total width counterparts in mean correlation coefficient (RBAR = 0.55, 0.46, 0.52, respectively). Strategic plans for increasing the utility of longleaf pine dendrochronology in the southeastern US include [1] saving remnant material (e.g., stumps, logs, and building construction timbers) from decay, extraction, and fire consumption to help extend tree-ring records, and [2] developing new chronologies in LTRN spatial gaps to facilitate broad-scale analyses of longleaf pine ecosystems within the context of the topical groups presented. [ABSTRACT FROM AUTHOR]

Megaherbivores play a critical role in the ecology of African savannas and grasslands. In addition, these systems are forecast to experience more frequent and severe droughts as a product of changes in the global climate. Thus, the continued conservation of megaherbivores and their associated ecosystems will require a better understanding of how megaherbivores respond to drought by shifting their movement, diet and social behaviour. We address this need by investigating the factors affecting changes in the abundance of common hippopotamus (Hippopotamus amphibius; hereafter: 'hippos') throughout the six major rivers of Kruger National Park, South Africa, during and following the severe drought of 2015/2016. Specifically, we aimed to understand the role of two environmental characteristics that have relevance to hippos and that changed in response to drought: vegetation condition and the extent of pooled surface water. In addition, we investigated the extent to which pre‐drought density affected changes in hippo abundance. Although vegetation and daytime refugia both appeared to influence pre‐drought hippo abundance, these factors were less important to the change in hippo abundance related to the drought. Instead, the response to drought was most strongly related to the pre‐drought abundance of hippos, where river segments supporting more than 50 individuals prior to the drought in 2015 decreased by more than half on average. Furthermore, we show that the degree of aggregation decreased from 2015 to 2016 because of the drought, but then began to increase again as the rains returned in 2017. Our results suggest that in addition to the large pools that support large aggregations of hippos in typical years, additional smaller pools are likely important for accommodating this drought‐induced dispersion. However, maintaining this distribution of pools will likely become more challenging as southern Africa's population and water demands increase. [ABSTRACT FROM AUTHOR]

The flexibility of UAV‐lidar remote sensing offers a myriad of new opportunities for savanna ecology, enabling researchers to measure vegetation structure at a variety of temporal and spatial scales. However, this flexibility also increases the number of customizable variables, such as flight altitude, pattern, and sensor parameters, that, when adjusted, can impact data quality as well as the applicability of a dataset to a specific research interest.To better understand the impacts that UAV flight patterns and sensor parameters have on vegetation metrics, we compared 7 lidar point clouds collected with a Riegl VUX − 1LR over a 300 × 300 m area in the Kruger National Park, South Africa. We varied the altitude (60 m above ground, 100 m, 180 m, and 300 m) and sampling pattern (slowing the flight speed, increasing the overlap between flightlines and flying a crosshatch pattern), and compared a variety of vertical vegetation metrics related to height and fractional cover.Comparing vegetation metrics from acquisitions with different flight patterns and sensor parameters, we found that both flight altitude and pattern had significant impacts on derived structure metrics, with variation in altitude causing the largest impacts. Flying higher resulted in lower point cloud heights, leading to a consistent downward trend in percentile height metrics and fractional cover. The magnitude and direction of these trends also varied depending on the vegetation type sampled (trees, shrubs or grasses), showing that the structure and composition of savanna vegetation can interact with the lidar signal and alter derived metrics. While there were statistically significant differences in metrics among acquisitions, the average differences were often on the order of a few centimetres or less, which shows great promise for future comparison studies.We discuss how these results apply in practice, explaining the potential trade‐offs of flying at higher altitudes and with alternate patterns. We highlight how flight and sensor parameters can be geared toward specific ecological applications and vegetation types, and we explore future opportunities for optimizing UAV‐lidar sampling designs in savannas. [ABSTRACT FROM AUTHOR]

Mitigating climate change requires us to constrain combustion in a double sense: decreasing both the use of fossil fuels and the flammability of the biosphere. Fire management by Indigenous peoples in Australia's northern savannas has been presented as a solution to offset the former and assist with the latter, leading to the foundation of a regional economy of projects generating 'premium' carbon credits on Indigenous lands. This article attends to the translational zone – predominantly made up of non‐Indigenous white professionals – that functions to configure the 'right story' of these credits across diverse epistemes and contexts. Following such commodities' interscalar connections, I suggest, helps illustrate the contingencies and contradictions produced by tradeable carbon, as individuals and organizations seek to maintain a niche within a changing climate and shifting global atmospheric relations. [ABSTRACT FROM AUTHOR]

The use of lime in reducing acidity, increasing nodulation and grain yield of field cowpea in Nigeria had not been determined. Hence, field experiments were conducted in 2020 and 2021 cropping seasons at the Landmark University, Omu-Aran, Nigeria. The study was undertaken to evaluate the effects of lime on soil chemical characteristics, growth, nodulation, and yield of cowpea on tropical-derived savanna. The treatments in each year consisted of five levels (0, 2.5, 5.0, 7.5 and 10 t/ha) of lime (CaCO3). The treatments were arranged in a RCBD and replicated three times. Findings showed that the application of lime improved soil chemical characteristics (pH, N, P, K, Ca, Na, Mg and CEC), growth, nodulation and yield of cowpea compared to the control. Lime application reduced acidity (H+Al3+) relative to the control. Lime increased the yield of cowpea from 0 to 2.5 t/ha after which there was a decrease. 2.5 t/ha lime increased pod weight of cowpea relative to the control by 51.2% in 2020 and 48.2% in 2021. 10 t/ha lime reduced pod weight of cowpea relative to the 2.5 t/ha by 237.62% in 2020 and 257.1% in 2021, the reduction in the yield of cowpea can best be explained by the presence of unfavourable soil pH conditions. Therefore, the optimum yield of the cowpea crop was achieved at 2.5 t/ha of lime for the agro ecological zone. [ABSTRACT FROM AUTHOR]

In Ghana’s Guinea savanna ecological zone, fuelwood is the primary source of energy for cooking and heating, but not much is known about the cultural importance of woody species as fuelwood. This study aimed to identify the plant species used as fuelwood and determine their cultural importance in Navrongo Forest District. Totally 246 households that rely on fuelwood as their primary energy source for heating and cooking were selected and interviewed using the free listing technique. The cultural importance index and relative importance index were used to determine the most culturally important species for fuelwood and preferences based on fuel attributes. A total of 32 plant species were identified to be used for fuelwood purposes; Anogeissus leiocarpa was identified to have the highest cultural importance index. The relative importance index revealed that Khaya senegalensis and Vitellaria paradoxa were the most important species based on their fuel attributes. Four species of conservation and economic importance (Khaya senegalensis, Parkia biglobosa, Pterocarpus erinaceus, and Vitellaria paradoxa) were identified as having high cultural importance and relative importance index for fuelwood purposes. It is recommended that species of conservation and economic importance should be evaluated due to the potential impact of their use as fuelwood on biodiversity and local economic development. [ABSTRACT FROM AUTHOR]

The study focused on the geospatial assessment of the physicochemical properties of soils at the Institute of Agricultural Research and Training, Ilora, Oyo State, Nigeria. Using the random survey method, 100 surfaces (0 to 20 cm) samples were collected and subjected to standard soil laboratory analyses. The variability of soil nutrients was examined using descriptive statistics, while spatial investigation and interpolation were achieved using the Ordinary krigging (OK) method. Crossvalidation accuracy with exponential and spherical models was used as a precision tool for the analyzed soil nutrients. Soil nutrient spatial trends were exponentially distributed across the area. Temporal predicted land surface temperature (LST), and soil-adjusted vegetation index (SAVI) were estimated through Landsat images of the years 2000 and 2020 using ArcGIS 10 software. The spectral variables - LST and SAVI were merged with soil nutrients to assess the maize suitability evaluation of the area. The LST and SAVI results revealed the qualitative differences in the studied area. The maize suitability showed that the studied soils ranged from moderately (85%), marginally (60%), and not suitable (< 40%). To increase the suitability of the soils for optimum maize production there is a need to enhance the limiting dominant factors such as undulating topography, rainfall, and erosion hazard. Hence, the study recommends the integration of geospatial techniques such as remote sensing covariate variables and exponential models as indispensable methods to assist farmers and policymakers in sustainable and precision agriculture. [ABSTRACT FROM AUTHOR]

In Oregon, an estimated 3% of the original Quercus garryana savanna remains seven generations after pioneer settlement. Consequently, the US Fish and Wildlife Service (USFWS), non-profit wildlife organizations, and Oregon state agencies and policy makers have put oak habitat, especially oak savanna restoration, among their highest priorities. "Oak savanna" is commonly defined as an area of large, open-growing oaks at a density of 4-5 trees per acre. Twenty-one years ago, Jolly Krautmann and I purchased a 400-acre farm that had an 85-acre oak savanna along the farm hillsides. Long neglected, it had become infested with many kinds of tall invasive weeds and vines. This paper summarizes specific measures that we have tried in oak savanna restoration. Despite initial failures, we feel we've succeeded in establishment of a stand of predominantly (65-85%) native grasses and wildflowers among the scattered open -growing oaks. Herein, we aim to offer insight and inspire others to engage in oak savanna restoration. [ABSTRACT FROM AUTHOR]

To assess the agronomic effects of sustainable okra production as impacted by goat manure (GM) and rice husk ash (RHA) on a community-based demonstration farm in Gombe State, field trials were carried out during the wet seasons of 2017 and 2018. The trails consisted of four levels of GM and RHA, each measuring 0.0, 5.0, 7.5, and 10.0 t ha-1 which were used on Kwadon's local cultivar of okra in a Randomized complete block design (RCBD) replicated four times. Findings revealed that days to 50% emergence and establishment count were not significantly (P>0.05) influenced by the application of GM and RHA, regardless of rates of application. Other growth-related indices were significantly (P<0.05) higher due to GM, such as plant height at 4, 5, and 6 WAS, number of leaves plant-1 at 4 WAS, and pod diameter. On the other hand, RHA significantly (P<0.05) increased plant height, the number of leaves plant-1 at 5 and 6 WAS, leaf area, shortened days to 50% flowering, and the number of pods plant-1 across the sampling periods and seasons. Similar to this, due to adequate mineralization of organic material through time and space, fresh okra's marketable weight increased in the 2018 season compared to the previous year. Thus, the application of 10.0 t ha-1 of both GM and RHA can be adopted in the production of okra in the study area to reduce greenhouse gas emissions resulting from the use of inorganic agrochemical inputs. [ABSTRACT FROM AUTHOR]

For over a century, deep roots have been assumed to allow trees to avoid competition with grasses (i.e., the two‐layer hypothesis). Yet, in part because it remains difficult to measure water uptake in the field, there has been a shift in savanna ecology away from the two‐layer hypothesis and towards alternative explanations of tree‐grass coexistence. Here, we combine hydrologic tracer experiments and soil water flow models to demonstrate how the distribution of active roots affects water uptake across a range of savanna conditions. Grass roots were shallower and provided pre‐emptive access to enough soil water to allow nearly continuous grass cover, but slightly deeper roots provided trees with more total water under most conditions. This 'some water now or more water later' tradeoff varied with precipitation amount, soil texture, and tree and grass relative root abundance in ways that helped explain tree and grass landscape abundance. [ABSTRACT FROM AUTHOR]

Bush encroachment is a habitat change phenomenon that threatens savanna and grassland ecosystems worldwide. In Africa, large carnivores in bush encroached landscapes must adjust to increasing woody plant cover and biomass, which could affect predation success at multiple stages through complex and context-dependent pathways. We highlight, interpret, and compare studies that assessed how bush encroachment or related habitat parameters affect the predation stages of large African carnivores. Bush encroachment may directly or indirectly affect predation success in various ways, including by: (1) altering habitat structure, which may affect hunting efficiency and prey accessibility; (2) changing prey abundance/distribution, with smaller species and browsers being potentially favoured; (3) influencing interference competition within the carnivore guild. For habitat or dietary specialists, and subordinate predators that are vulnerable to both top-down and bottom-up ecosystem effects, these alterations may be detrimental and eventually incur population fitness costs. As the threat of bush encroachment continues, future studies are required to assess indirect effects on competitive interactions within the large African carnivore guild to ensure that conservation efforts are focused. Additionally, to better understand the effects of bush encroachment across Africa, further research is necessary in affected areas as overall little attention has been devoted to the topic. [ABSTRACT FROM AUTHOR]

The rangelands of Africa have been subject to substantial changes. The changes in the savanna rangelands ecology were from different points of view. This study constructs the perceptions of Boorana pastoralists on historic changes in rangelands post-1992 based on the Gadaa timelines. The construction of pastoralist perceptions can make an immense contribution to comprehending the rate, trends, indicators, and impacts of rangeland degradation in Boorana rangelands. This study thus points out that pastoralists can better understand and describe rangeland conditions and factors associated with such changes in the Gadaa periods. The study was based on the data collected from 332 pastoralists using a survey questionnaire and qualitative data, and the results were analyzed using descriptions of responses and narrations of cases. The study revealed that the conditions of the Boorana rangelands have been deteriorating over time and rangeland degradation showed unprecedented growth trends, mainly attributed to vegetation, rangeland production, human, environmental, and climate change-related factors. The study also shows that the progressive degradation of rangeland resources has jeopardized rangeland production, livestock productivity, and human well-being in the Boorana rangeland system. The study suggests that the recognition and promotion of indigenous ecological knowledge of pastoralists could sustain the pastoralist community in arid and semiarid rangelands. It is, therefore, imperative to understand pastoralists' knowledge of rangeland ecology for sustainable management of rangeland resources. [ABSTRACT FROM AUTHOR]

He argues that it is the large brain that shapes primate ecology, slowing the age of first reproduction which has to be compensated for by a longer lifespan to maintain positive population growth. Norman Owen-Smith (NOS) is an eminent South African ecologist well known for his concept of mega herbivores, and prolific author on diverse aspects of African herbivore ecology in a career spanning half a century. [Extracted from the article]

We all learned that the origin of Homo sapiens lies in Africa, but why there? Owen-Smith has crafted a book for a broad audience interested in savanna ecology, Africa's nature, anthropology, and human evolution. Primates were present in South America and Eurasia, and Australia had tree-dwelling mammals not so different from primates. [Extracted from the article]

Research on African bees remains scarce. For instance, the mechanism underlying ecology for ground-nesting stingless bees in ecosystems remain poorly documented. The main goal of this study was to assess what determines habitat preference for stingless bees playing an important role in plant pollination. The case of Plebeina armata (Magretti, 1895) (Hymenoptera, Apidae, Meliponini) was taken as a model. We collected information from an unsuccessful project of beekeeping of P. armata recently ran in the Ruvubu National Park, the widest protected area in Burundi in northeast of the country. We also conducted semi-structured interviews among people, mainly beekeepers, neighboring the park to document local traditional knowledge of stingless bees. Since our respondents indicated that Plebeina nested in termite mounds, we extensively sampled termite species associated with mounds in the area. We also collected soil samples from mounds with and without the bee. Wilcoxon tests were used to compare soil properties of mounds according to the occurrence of P. armata. The results of our study showed that people neighboring the Ruvubu National Park had deep knowledge on the ecology of stingless bees. Our findings also suggested that the beekeeping of Plebeina would have failed in the area due to the lack of its specific nesting requirements. This bee nested in active Macrotermitinae mounds, probably in search of optimal conditions of humidity, temperature and for security. Mounds with a sol rich in coarse silt seemed not to attract Plebeina ; probably, those termitaria may not be strong to serve as a bulwark against thermal fluctuations. Our results raise the question of taking account of the traditional knowledge to any attempt to species domestication. Understanding the ecological adaptation of ground-nesting stingless bees is particularly important for restoration and conservation of their habitats and to any attempt to their beekeeping or meliponiculture in an area. • Traditional knowledge on stingless bees was examined to understanding Plebeina armata ecology in the savanna woodland. • P. armata colonies were found in Macrotermitinae mounds. • Wild fires and termitaria destruction should be discouraged to preserve habitats of ground-nesting stingless bees. [ABSTRACT FROM AUTHOR]

The article presents the discussion on researchers struggling to recover genetic samples surviving the hot humid climate forming fragmented savannalike "islands" for many species .