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AbstractCoarse aerosol particles containing chloride in tropical forests are significant for understanding biogeochemical cycles and atmospheric processes, with implications for environmental health and climate change mitigation. This study explored the sources of super-coarse carbonaceous aerosol particles containing chloride in a tropical savanna climate. Aerosol samples were collected from an agro-forest site in Thailand during the dry season and analyzed using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and Fourier-transform infrared (FTIR) spectroscopy. By examining the morphology and elemental compositions of individual aerosol particles, along with employing Positive Matrix Factorization (PMF) and backward trajectory analysis, potential sources were identified. The findings revealed two primary sources for the super-coarse aerosol particles: a mixture of biomass burning smoke and inorganic salts (likely from saline soil and sea salt), as well as halophilic fungal spores. FTIR analysis indicated the presence of compounds linked to biomass burning and clay minerals, influenced by prevailing northeast and southeast winds. Recommendations for future research include continued monitoring, correlation with meteorological parameters, and the application of transmission electron microscopy (TEM) for more detailed visualization and confirmation of aerosol sources.

Soils and climate change / Rattan Lal and Ronald F. Follett -- A national assessment of soil carbon sequestration on cropland: a microsimulation modeling approach / Steven R. Potter [and four others] -- Modeling soil organic carbon change in Canadian agroecosystems: testing the introductory carbon balance model / A.J. VandenBygaart [and five others] -- Soil organic carbon stocks with depth and land use at various U.S. sites / Ronald F. Follett [and four others] -- Influence of climate and land use change on carbon in agriculture, forest, and peatland ecosystems across Canada / J.S. Bhatti and C. Tarnocai -- Soil carbon sequestration in different ecoregions of Mexico / Claudio Balbontín [and three others] -- Management of dryland cropping systems in the U.S. Great Plains: effects on soil organic carbon / Mark A. Liebig, M.M. Mikha, and Kenneth N. Potter -- Management effects on soil organic carbon in Texas soils / Kenneth N. Potter, Paul W. Unger, and H. Allen Torbert -- Soil total carbon content, aggregation, bulk density, and penetration resistance of croplands and nearby grasslands / Paul W. Unger -- Soil organic carbon and nitrogen sequestration in irrigated cropping systems of the central Great Plains / Ardell D. Halvorson [and three others] -- Organic carbon stocks and sequestration potential of vertisols in the coast prairie major land resource area of Texas / Lee C. Nordt and Larry P. Wilding -- Influence of management on soil organic carbon dynamics in northern mixed-grass rangeland / G.E. Schuman [and five others] -- Belowground carbon storage and dynamics accompanying woody plant encroachment in a subtropical savanna / T.W. Boutton [and three others] -- Soil organic carbon sequestration by biochemically recalcitrant biomacromolecules / Klaus Lorenz [and three others] -- Stable-carbon isotopes of U.S. Great Plains soils and climate events during the Holocene / Steven W. Leavitt and Ronald F. Follett -- Effects of elevated atmospheric carbon dioxide on soil carbon in terrestrial ecosystems of the southeastern United States / G. Brett Runion [and three others] -- Linking soil organic carbon and environmental quality through conservation tillage and residue management / Alan J. Franzluebbers -- Crop residue management and soil carbon dynamics / Humberto Blanco-Canqui and Rattan Lal -- Organic carbon accumulation in reclaimed mine soils of the western United States / L.J. Ingram [and three others] -- Terrestrial carbon sequestration potential in reclaimed mine land ecosystems to mitigate the greenhouse effect / Raj K. Shrestha, David A.N. Ussiri, and Rattan Lal -- An evaluation of methodologies for assessing geogenic carbon in mine soils of the eastern United States / P.A. Jacinthe [and three others] -- Carbonaceous materials in soil-derived dusts / R. Scott Van Pelt and Ted M. Zobeck -- Carbon dynamics in urban soils / Klaus Lorenz and Rattan Lal -- Priorities in soil carbon research in response to climate change / Rattan Lal and Ronald F. Follett.

The Araguaia River Basin covers a considerable extent of Brazilian Savanna (locally called Cerrado) and part of Amazon Tropical Rainforest, embracing high biodiversity and a vast flooding area. This region has been converted to agricultural lands since 1970s, for the past four decades, leading to a fragmented land- scape that holds one of the few large remaining blocks of Cerrado primary vegetation. Therefore, to as- sess the degree of preservation of this area a 2007 primary vegetation map was derived through Boolean operations using land use and land cover maps from 1975, 1985, 1996 and 2007, from digital classifica- tion of Landsat MSS and TM images. To evaluate the role of driving factors on the presence of pristine vegetation, a logistic regression analyses was performed. Tested factors were: distance from roads and cities, terrain slope, land tenure, soil fertility and flooding. We found statistical significant values (p < .05) showing that distance from roads and cities, the increase in slope, the presence of protected areas, indige- nous lands, wetlands and areas with low fertility have positive influence on the presence and maintenance of these pristine areas. The occurrence of original vegetation in many cases is associated with environ- mental constraints that difficult or do not allow agricultural use. Analysis of physical and political factors, which may have direct or indirect influence on the conservation and degradation of native vegetation are very important for the comprehension of the dynamics of regional land use, and provide supporting in- formation for a more efficient and sustainable regional landscape planning.

The REDD+ scheme of the United Nations intends to offer developing countries financial incentives to reduce the rates of deforestation and forest degradation for reducing global CO2 emissions. This is combined with building carbon stocks in existing wooded ecosystems and fostering other soil, biodiversity and water conservation objectives. Successful application of REDD+ to the Xylophone Triangle of West Africa faces substantial challenges and risks to both meeting REDD+ objectives and to the local people's rights and livelihoods. The transnationality of the culturally coherent area requires collaboration of three national governments. The opportunities, however, are great to capitalize on the region's biodiversity, the well-developed traditional ecological knowledge and the use of local medicinal plants as an integral part of the agro-ecosystem. Possibilities open to, not only sequester carbon, but also to increase the resilience of the ecosystem and of independent rural livelihoods in the face of climate change and globalization.

We conducted on-farm trials in the southern Guinea Savanna of Ghana in 2016 and 2017 to evaluate soyabean response to three fertiliser blends to guide farmers towards profitable adoption of appropriate phosphorus (P) fertiliser blend for improved soyabean production. Old YARA Legume (OYL), New YARA Legume (NYL) and Triple Superphosphate (TSP) fertiliser blends were evaluated. In both years, the P fertiliser blends were evaluated in a Randomised Complete Block Design with 20, 30, and 40 kg P ha -1 application rates together with control. P fertiliser application increased soyabean yields by 1070 kg ha -1 . In 2016, fertiliser blend use efficiency (BUE) ranged from 2.9 kg grain per kg fertiliser blend applied with the NYL applied at 40 kg P ha -1 to 7.4 kg grain per kg fertiliser blend applied with the TSP applied at 40 kg P ha -1 with significant differences between treatments. In 2017, BUE ranged from 2.5 kg grain per kg fertiliser blend applied with OYL applied at 40 kg P ha -1 to 9.2 kg grain per kg fertiliser blend applied with the TSP applied at 40 kg P ha -1 with significant differences between treatments. However, P use efficiency did not significantly differ between the different treatments both in the 2016 and 2017 trials. In both 2016 and 2017 trials, the highest benefit cost ratio was attained at the lowest application rate for all the three fertiliser blends suggesting the need to review the current application rate of 30 kg P fertiliser ha -1 promoted in northern Ghana. Furthermore, the provision of credit and/or subsidy for farmers by the government is required to enable uptake and utilisation of fertilisers by farmers

Landscapes constitute the manifestation of natural and anthropic elements and its structure is the result of physical, biological, political, economic and social interactions, fragmented or connected for different land uses. Drawing on this, our study aims to analyze the environmental landscape quality using ecological indices in the Tietê-Jacaré Hydrographic Basin – SP, Brazil between 2007 and 2017. A set of Environmental Quality Indices was used to analyze the susceptibility of the ecological components to the effects of human activities. The Environmental Quality Index of Vegetation, the Environmental Quality Index of Water Resources and the Environmental Vulnerability Index were used to assess the condition of ecological sustainability of the landscape. It was identified a reduction in the areas with native vegetation with a loss of 2.72%, representing over 32,149 ha, an expansion of agricultural areas of 2.05% (24,507.53 ha) and consequently a reduction of the environmental quality in the landscape. These impacts compromise the ecosystem structure and ecosystem services, per example, through the impacts on soils that support vegetation cover as the major sources of energy for terrestrial life. The observed intensification of anthropogenic activities and the corresponding reduction of natural areas often lead to the loss of biodiversity and the benefits that its ecosystem services provided to people.

Our study aimed at deepen our understanding of relationships between soil properties and vegetation distribution in metalliferous ecosystems of Tenke-Fungurume in the Democratic Republic of Congo. The first question concerned the differences and similarities between soils of the main vegetation units and four variation factors of soil properties were summarized by multivariate analysis. They were all linked to lithology and significantly contributed to explain the distribution of vegetation units. Our result suggest that the variation of soil properties which is observed within the various vegetation units (rocky steppe savanna, sward, and steppe savannas on slope or on Dembo) should partially be attributed to differences of geochemical composition of rocks between sites but the main source of variability is to be found inside each hill. The soil contamination in Cu and Co originates from rock weathering and besides site effect and topographic distribution of the rocks, the variability of soil properties within one vegetation unit may be due to variability of soil parent material and not only to erosion. The second question dealt with the changes of soil properties at small distances. Metric variation was studied from transects between adjacent vegetation units. Our results showed that the abrupt changes of vegetation units which were clearly identified on the field were all truly explained by the variations of one or more properties linked to lithology. The key point being the Cu bioavailability. ; Peer reviewed

International audience ; Our study aimed at deepen our understanding of relationships between soil properties and vegetation distribution in metalliferous ecosystems of Tenke-Fungurume in the Democratic Republic of Congo. The first question concerned the differences and similarities between soils of the main vegetation units and four variation factors of soil properties were summarized by multivariate analysis. They were all linked to lithology and significantly contributed to explain the distribution of vegetation units. Our result suggest that the variation of soil properties which is observed within the various vegetation units (rocky steppe savanna, sward, and steppe savannas on slope or on Dembo) should partially be attributed to differences of geochemical composition of rocks between sites but the main source of variability is to be found inside each hill. The soil contamination in Cu and Co originates from rock weathering and besides site effect and topographic distribution of the rocks, the variability of soil properties within one vegetation unit may be due to variability of soil parent material and not only to erosion.The second question dealt with the changes of soil properties at small distances. Metric variation was studied from transects between adjacent vegetation units. Our results showed that the abrupt changes of vegetation units which were clearly identified on the field were all truly explained by the variations of one or more properties linked to lithology. The key point being the Cu bioavailability. ; Cette étude a pour objet les relations entre propriétés des sols et distribution des unités de végétation dans les écosystèmes métallifères de Tenke-Fungurume au Katanga en République Démocratique du Congo. La première question étudiée visait l'estimation des différences et similitudes entre sols des principales unités de végétation. La caractérisation des sols a permis d'identifier, par analyse multivariée, quatre facteurs de variation des propriétés physico-chimiques des sols qui sont tous ...

In Democratic Republic of Congo (DRC), cassava covers more than half of the area under cultivation and is permanently consumed by more than 70% of the population for its roots and about 80% for its leaves, which are one of the main vegetables in the country. National cassava production suffered a setback in the early 1990s and an annual arithmetic reduction of the cassava production, from this period to the start of a program on the rehabilitation of the crop. The main objective of the program was to develop varieties with high dry yield and resistant to cassava diseases and pests mainly the cassava mosaic disease (CMD) because the latter was identified as the major cause for the low production recorded. As and when the program gained momentum, many other factors appeared to have important role for the effective recovery of cassava production. Soil fertility management and cultural practices are amongst them. This study was conducted in this context in two different agro-ecological zones (Litoy in Kisangani hinterlands in forest zone and Plateau de Bateke at the East of Kinshasa in savannah zone). The soil of Litoy is heavier than the one of Plateau des Bateke whose sand content is higher than 90%. The method of land preparation influenced the production of cassava roots and leaves in the grassy fallows of the forested areas of the Kisangani region. A 45% increase of the root yield was obtained in this area when the soil was plowed. An stable yield of 14 t/ha was obtained in the Bateke plateau savannah regardless of the land preparation method. The position/orientation of cuttings at planting did not indicate significant statistical differences. However, higher gross profit margins were obtained on plowed land with US$2500/ha compared to US$1500/ha on no tilled land. ; Peer Review

Foreword / Johan T. du Toit -- Part 1. The physical cradle: Land forms, geology, climate, hydrology and soils -- Part 1. Synthesis: Structure of the physical cradle -- Part 2. The savanna garden: Grassy vegetation and plant dynamics -- Section 2. Synthesis: Savanna structure and dynamics -- Part 3. The big mammal menagerie: Herbivores, carnivores and their ecosystem impacts -- Part 3. Synthesis: Movers of savanna dynamics: Grazers, elephants and fires -- Part 4. Evolutionary transitions: From primate ancestors to modern humans.

International audience ; Our study aimed at deepen our understanding of relationships between soil properties and vegetation distribution in metalliferous ecosystems of Tenke-Fungurume in the Democratic Republic of Congo. The first question concerned the differences and similarities between soils of the main vegetation units and four variation factors of soil properties were summarized by multivariate analysis. They were all linked to lithology and significantly contributed to explain the distribution of vegetation units. Our result suggest that the variation of soil properties which is observed within the various vegetation units (rocky steppe savanna, sward, and steppe savannas on slope or on Dembo) should partially be attributed to differences of geochemical composition of rocks between sites but the main source of variability is to be found inside each hill. The soil contamination in Cu and Co originates from rock weathering and besides site effect and topographic distribution of the rocks, the variability of soil properties within one vegetation unit may be due to variability of soil parent material and not only to erosion.The second question dealt with the changes of soil properties at small distances. Metric variation was studied from transects between adjacent vegetation units. Our results showed that the abrupt changes of vegetation units which were clearly identified on the field were all truly explained by the variations of one or more properties linked to lithology. The key point being the Cu bioavailability. ; Cette étude a pour objet les relations entre propriétés des sols et distribution des unités de végétation dans les écosystèmes métallifères de Tenke-Fungurume au Katanga en République Démocratique du Congo. La première question étudiée visait l'estimation des différences et similitudes entre sols des principales unités de végétation. La caractérisation des sols a permis d'identifier, par analyse multivariée, quatre facteurs de variation des propriétés physico-chimiques des sols qui sont tous liés à la lithologie. Nos résultats suggèrent que la variabilité observée entre unités de végétation (savane steppique enrochée, pelouse et savanes steppiques de pente ou de Dembo) est partiellement liée aux différences de composition géochimique des matériaux parentaux entre les sites mais également et principalement due à une variabilité importante du fond géochimique au sein de chaque unité de végétation. Les contaminations des sols en Cu et Co proviennent de l'altération des roches et la variabilité des teneurs mesurées au sein des unités de végétation peut aussi bien résulter de la variabilité des matériaux parentaux que des processus d'érosion.La deuxième question visait l'étude des transitions entre unités de végétation à l'échelle métrique. Les changements abrupts de végétation ont été clairement mis en parallèle avec des modifications des propriétés des sols, en lien avec la lithologie encore une fois. La clef de la distribution de ces unités est la disponibilité du cuivre.

Intro -- Contents -- Preface -- Chapter 1 -- Historical Ecology to Inform Restoration of Oak Savanna in Michigan -- Abstract -- Introduction -- Literature Review -- Climate System -- Global Climate Change Trend -- Climate Change Trend in the Great Lakes Region and Michigan -- Influence of Competition on Tree Growth -- Oak Ecology -- Forest Restoration -- Dendrochronology -- Oak Savanna Restoration -- Conclusion -- Acknowledgments -- References -- Chapter 2 -- Coniferous Forest Ecosystems -- (With a Reference to Soil Mesofauna): A Literature Review -- Abstract -- Coniferous Forest Ecosystems -- Coniferous Forest Soil -- General Character of the Coniferous Forest Fauna -- Vertical Stratification of the Topsoil -- Collembola as an Important Part of Soil Mesofauna -- References -- Chapter 3 -- City Gulls and Their Rural Neighbours: Changes in Escape and Agonistic Behaviour along a Rural-To-Urban Gradient -- Abstract -- Introduction -- Material and Methods -- Study Area and Species -- Escape Behaviour (Boldness) -- Agonistic Behaviour (Aggression) -- Degree of Urbanisation -- Statistical Analysis -- Results -- Escape Behaviour (Boldness) -- Agonistic Behaviour (Aggression) -- Correlation of Boldness and Aggression -- Discussion -- Escape Behaviour (Boldness) -- Agonistic Behaviour (Aggression) -- Acknowledgments -- References -- Biographical Sketch -- Chapter 4 -- A Comprehensive Study of the Statistical Effects of Maize Harvesting on Water Quality in Ecuadorian Soils from 2012 to 2016 -- Abstract -- Introduction -- Materials and Methods -- Study Area -- Methods and Data Collection -- Water Quality Analysis -- Analysis of Variance (ANOVA - Multifactorial) -- Regression and Correlation Analyses -- Results -- Discussion -- Conclusion -- References -- Chapter 5 -- Hydrochemical Study at Águas De Santa Bárbara Spa, São Paulo State, Brazil.

Intro -- Foreword -- Acknowledgments -- Contents -- About the Book -- Part IForeword 1 + Photo -- 1 The Megadiverse Rupestrian Grassland -- Abstract -- 1.1 The Harsh and Unique Rupestrian Grassland -- 1.2 Synergism Among Drivers and Environmental Filters Leading to Biodiversity -- 1.3 The Human Dimension in the Rupestrian Grasslands -- 1.4 Book Sections -- Acknowledgements -- References -- 2 The Physical Environment of Rupestrian Grasslands (Campos Rupestres) in Brazil: Geological, Geomorphological and Pedological Characteristics, and Interplays -- Abstract -- 2.1 The Geological Control -- 2.2 Landforms and Geomorphological Control -- 2.3 Soils, Landforms and Rupestrian Grassland Vegetation on Different Lithologies in Brazil -- 2.3.1 Ferruginous Rupestrian Grasslands -- 2.4 Canga: A Definition -- 2.5 Case Study 1-Island of Ferruginous Rupestrian Physiognomy in the Midst of the Amazonia Forest: A Sequence of Carajás Plateau, Brazilian Eastern Amazonia -- 2.5.1 Study Site -- 2.5.2 Open Rupestrian Grassland -- 2.5.3 Shrubby Rupestrian Grassland -- 2.5.4 "Capão" Forest -- 2.6 Case Study 2-Canga Soils of the Iron Quadrangle, Serra Da Moeda, Minas Gerais, Brazil -- 2.7 General Aspects of Canga Soils-A Discussion -- 2.8 Case Study 3-Rupestrian Grassland on Metarenites and Metapellites from Serra Geral State Park, North Minas Gerais -- 2.8.1 High Top with Open Rupestrian Grassland on Metapellites -- 2.8.2 Slope and Crests with Open Rupestrian Grassland with Vellozia on Rocky Outcrops -- 2.8.3 Rupestrian Savanna (Cerrado Rupestre) on Escarpments -- 2.9 Case Study 4-A Soil Sequence of Quartzite and Micaceous Quartzite from the Espinhaço Range in the Sempre-Vivas State Park, Minas Gerais States -- 2.9.1 Study Area -- 2.9.2 Open Rupestrian Grassland with Vellozia on Litholic Neosols -- 2.9.3 Open and Shrubby Rupestrian Savanna on Cambisols.

Large areas in the tropics and at mid-latitudes experience pronounced seasonality and inter-annual variability in rainfall and hence water availability. Despite the importance of these seasonally dry ecosystems (SDEs) for the global carbon cycling and in providing ecosystem services, a unifying ecohydrological framework to interpret the effects of climatic variability on SDEs is still lacking. A synthesis of existing data about plant functional adaptations in SDEs, covering some 400 species, shows that leaf phenological variations, rather than physiological traits, provide the dominant control on plant-water-carbon interactions. Motivated by this result, the combined implications of leaf phenology and climatic variability on plant water use strategies are here explored with a minimalist model of the coupled soil water and plant carbon balances. The analyses are extended to five locations with different hydroclimatic forcing, spanning seasonally dry tropical climates (without temperature seasonality) and Mediterranean climates (exhibiting out of phase seasonal patterns of rainfall and temperature). The most beneficial leaf phenology in terms of carbon uptake depends on the climatic regime: evergreen species are favoured by short dry seasons or access to persistent water stores, whereas high inter-annual variability of rainy season duration favours the coexistence of multiple drought-deciduous phenological strategies. We conclude that drought-deciduousness may provide a competitive advantage in face of predicted declines in rainfall totals, while reduced seasonality and access to deep water stores may favour evergreen species. This article has been contributed to by US Government employees and their work is in the public domain in the USA.