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Christopher L. Dutton; Amanda L. Subalusky; Troy D. Hill; Julie C. Aleman; Emma J. Rosi; Kennedy B. Onyango; Kanuni Kanuni; Jenny A. Cousins; A. Carla Staver; David M. Post
basins; carbon; dry season; ecosystems; environmental factors; land use; mercury; nitrogen; paleoecology; people; pollution load; rivers; sediments; watersheds; wetlands; wildebeest; Eastern Africa; Nile River
Abstract:
... The Mara River basin is a trans-boundary basin of international importance. It forms the headwaters of the Nile River and serves as the primary dry season water source for an estimated 1.1 million rural people and the largest remaining overland migration of 1.4 million wildebeest in the Serengeti-Mara Ecosystem. Changes throughout the basin are impacting the quantity and quality of the Mara River, ...
... In a forest-scarce country like Iran, the open semi-arid Zagros forests are the single-most important forest region, yet their contribution to rural livelihoods remains inadequately understood. Here our primary focus is on analyzing the quantitative contributions of these oak-pistachio tree savannas to rural household incomes in Malekshahi County, Ilam Province, considering both cash and subsisten ...
Landsat; algorithms; artificial intelligence; data collection; dry season; ecosystem services; logging; monitoring; remote sensing; tropical forests; Amazonia; Brazil
Abstract:
... Hundreds of millions of hectares of tropical forest have been selectively logged, either legally or illegally. Methods for detecting and monitoring tropical selective logging using satellite data are at an early stage, with current methods only able to detect more intensive timber harvest (>20 m³ ha⁻¹). The spatial resolution of widely available datasets, like Landsat, have previously been conside ...
Escherichia coli; cluster analysis; coliform bacteria; data collection; decision making; dissolved oxygen; dry season; land use; nitrogen; nutrients; oxygen; phosphorus; planning; population density; principal component analysis; rural areas; sanitation; spring; surface water; temperature; topography; total nitrogen; total phosphorus; urban areas; urbanization; variance; water management; water pollution; water quality; winter
Abstract:
... The externalities generated by disorderly urbanization and lack of proper planning becomes one of the main factors that must be considered in water resource management. To address the multiple uses of water and avoid conflicts among users, decision-making must integrate these factors into quality and quantity aspects. The water quality index (WQI), using the correlation matrix and the multivariate ...
... Choruses are commonly observed phenomena in both terrestrial and aquatic environments and are the product of species vocalizing contemporaneously usually at dawn and dusk. This study analyzes the composition and temporal distribution of anuran choruses at a recently built artificial pond in Southeast Brazil. Data were collected using Passive Acoustic Monitoring devices set to record 24-hours per d ...
... Intensive silvopastoral systems (ISS) are a sustainable alternative to monoculture systems (MS). The presence of trees and legumes improves animal welfare due to the increased food quality and quantity and the presence of shade while providing a variety of environmental services. As cattle behaviour is greatly affected by environmental conditions, knowledge on the behavioural trade-offs that cattl ...
... This paper presents data collected in 2013, 2014 and 2015 on the cultural practices and agronomic performance of cropping systems in 500 lowland rice fields located in five regions of three West African countries, Benin, Mali and Sierra Leone. Data were collected in two stages. In the first stage, the main regions containing inland valleys were identified in each of the three countries and the mos ...
... Even though agricultural lands provide abundant food to aerial insectivorous bats (AIB), our understanding of how spatio-temporal factors affect their foraging behavior in these habitats is limited and mostly restricted to temperate regions. In this study, we examined species richness, composition and patterns of activity of AIB in rice fields in the northwestern Llanos of Venezuela. Between 2013 ...
... During the first Intensive Observation Period (IOP1) of the SHADOW (SaHAran Dust Over West Africa) campaign carried out during March–June 2015, the Mbour site (Senegal) was reinforced with a large setup of in-situ and remote sensing instruments to measure the aerosol optical, physical and chemical properties as well as the atmospheric dynamical features over the site. Here, we use this dataset to ...
Edmund Kyei Akoto-Danso; Delphine Manka’abusi; Christoph Steiner; Steffen Werner; Volker Häring; George Nyarko; Bernd Marschner; Pay Drechsel; Andreas Buerkert
... Agricultural production needs to increase, particularly in sub-Saharan Africa, many rural people are undernourished, and the urban population is growing rapidly. It is worrisome that on many West African soils with low cation exchange capacity and soil organic carbon content, mineral fertilization is rather inefficient. Under these conditions, wherever available untreated wastewater is used for ir ...
aerosols; air pollution; air quality; altitude; case studies; dry season; lidar; meteorology; models; moderate resolution imaging spectroradiometer; mountains; satellites; Nepal
Abstract:
... Kathmandu is the capital city of Nepal and a ‘hotspot’ of urban air pollution in South Asia. Its bowl-shaped structure (altitude 1300 m above sea level (masl); floor area 340 km2) surrounded by tall mountains provides a unique case study for analyzing pollution trapped by topography and local meteorology. In the absence of long-term in-situ observations, for the first time the columnar aerosol loa ...
... Alkylphenol ethoxylates (APEOs) are one of the most widely used classes of surfactants, but they are also ubiquitous environmental pollutants and known endocrin-disrupting chemicals. This study is the first to investigate the spatiotemporal variations and possible sources of APEOs and their metabolites, including nonylphenol ethoxylates (NPEOs) and octylphenol ethoxylates (OPEOs), in coastal sedim ...
... A new calanoid copepod, Allodiaptomus nongensis n. sp., is herein described based on samples collected from the Xe Lanong River (a tributary of the Mekong River), and 13 other localities in Central Laos. This is the sixth species of the genus Allodiaptomus Kiefer, 1936. The other five members in the genus were recorded from India, South China, Cambodia, Thailand, and Vietnam. The features that sta ...
... The reproductive activity of most of tropical Andean snakes is unknown, especially for fossorial species. An undescribed species of Atractus from Cordillera Oriental of Colombia occupies a habitat that undergoes two rainy seasons and two dry seasons. This strongly seasonal climate suggests that the reproductive phenology of the species might be seasonal or continuous with reproductive peaks relate ...
Formicidae; biotic factors; canopy; dry season; nectaries; species richness; tree crown; tree height; trees; tropical dry forests
Abstract:
... Canopy ecology is a fast-growing field, but still a scientific frontier in many ecological aspects. For instance, the hypothesis that tree traits shape patterns in ant-plant interactions lacks data, notably for tropical canopies in different successional stages. In this study, we investigated canopy traits, such as tree height, the presence of extrafloral nectaries (EFNs), connectivity among tree ...
aquifers; atmospheric deposition; case studies; dry season; hydrograph; ions; land use; river flow; rivers; socioeconomic development; sodium chloride; surface water; water management; water quality; water quantity; watershed management; watersheds; South Africa
Abstract:
... Globally, the dependence of river systems to delayed discharge of subsurface water to augment flows during dry seasons is well documented. Discharge of fresh subsurface water can dilute concentrated river flow quality during reduced flow. Observed and reported results on the Berg River’s declining water quantity and quality are a concern to the regions socio-economic growth and environmental integ ...
... The diversity of arbuscular mycorrhizal fungi (sub-phylum Glomeromycotina) in two contrasting coastal ecosystems (dunes and restinga) at Peró Beach, Rio de Janeiro state, Brazil was evaluated at the end of the rainy (May) and dry (November) seasons, in 2014. A total of 22 species belonging to ten genera and five families were recorded. Glomus macrocarpum and Rhizoglomus microaggregatum had large b ...
Neotropics; calcium; cerrado; dry season; ecophysiology; herbs; leaves; nutrient content; nutrients; plant physiology; potassium; rain; savannas; shrubs; trees; water content; water shortages; wood density; Brazil
Abstract:
... In seasonal systems, species have specific traits to deal with water shortage. This is the case for plants in Neotropical savannas, where the dry season can endure 3 to 5 months without rain. Ecophysiological strategies to deal with the dry period are well known for savanna trees, however little is known for non-arboreal species such herbs and subshrubs concerning their water use strategies. In th ...
droplets; dry season; hydrophilicity; hydrophobicity; runoff; soil organic matter; soil water; volumetric water content; water content; wet season; wetlands
Abstract:
... Soil water content is the most effective factor associated with the hydrophobic and hydrophilic changes in a soil. Water repellency in soils, is not a permanent feature; it can be reached in the dry season and reduced or eliminated in the wet season It can be said that in terms of moisture, there is a critical region that is defined as the threshold moisture content, where in lower moisture, the s ...
... Water requirement is sensitive to the impacts of climate change, especially in Bangladesh because of limited freshwater availability in the dry season, despite the fact that the country’s agriculture sector requires large quantities of water for the crop production. Hence, gaining a better understanding of changes in water requirements in Bangladesh during dry periods is important in the managemen ...
Daniel Mercado-Garcia; Eveline Beeckman; Jana Van Butsel; Nilton Deza Arroyo; Marco Sanchez Peña; Cécile Van Buggendhoudt; Nancy De Saeyer; Marie Anne Eurie Forio; Karel A. C. De Schamphelaere; Guido Wyseure; Peter Goethals
altitude; aquatic habitat; citizen participation; corporate social responsibility; dry season; ecotoxicology; environmental knowledge; environmental monitoring; gold; groundwater; land use; mining; mountains; politics; pollutants; stakeholders; water quality; watersheds
Abstract:
... Water quality assessments provide essential information for protecting aquatic habitats and stakeholders downstream of mining sites. Moreover, mining companies must comply with environmental quality standards and include public participation in water quality monitoring (WQM) practices. However, overarching challenges beyond corporate environmental responsibility are the scientific soundness, polit ...
Cladocera; Copepoda; Cyanobacteria; Rotifera; biotic factors; climate change; dry season; electrical conductivity; environmental factors; models; nauplii; pH; water supply; water temperature; winter; zooplankton; Brazil
Abstract:
... Evolutionary computation has been applied to predict the occurrence of massive cyanobacteria proliferations; in the present study, this tool was further used to explore the factors responsible for maintaining picocyanobacterial dominance. Aiming to increase the understanding of factors that promote dominance of picocyanobacteria in tropical reservoirs, we chose two reservoirs used for water suppli ...
... Low indigenous soil fertility is cited as a major problem in Uganda, where trees are integrated with bananas. Dominant trees were subjected to pruning regimes; 0, 25 and 50%. Litter decomposition was assessed using 480 bags (4 bags per tree × 4 trees × 3 regimes × 5 sites × 2 seasons). Decomposition was in order Ficus natalensis > Albizia coriaria > Mangifera indica > Artocarpus heterophyllus and ...
air pollution; air quality; ammonia; analysis of variance; burning; carbon monoxide; computer software; dry season; geographic information systems; health hazards; human health; hydrogen sulfide; municipal solid waste; nitrogen dioxide; pollutants; samplers; sawmills; sulfur dioxide; waste disposal sites; Nigeria
Abstract:
... Indiscriminate disposal and open burning of sawmill and municipal solid wastes constitute hazards to the quality of the immediate environment and human health. This study assessed the levels of pollutants emitted by burning sawmill and municipal wastes, and their potential hazards. Nine selected sawmills and 6 municipal solid-waste dumps in Abeokuta metropolis were investigated. During waste burni ...
... Few plant-insect interactions have been documented in semi-arid savannas. The reciprocal benefits that termites derive from plants in the ecosystem remain poorly studied. We studied the association between Carissa bispinosa (thorny shrub), and Trinervitermes trinervoides, termite mounds in Nylsvley nature reserve, South Africa and further assessed whether the association changed in its importance ...
Soil and Water Assessment Tool model; anthropogenic activities; basins; decision making; dry season; forests; land use change; planning; rivers; runoff; semiarid zones; spring; water management; watersheds; wet season; winter; China
Abstract:
... Attributing runoff change to different drivers is vital in order to better understand how and why runoff varies, and to further support decision makers on water resources planning and management. Most previous works attributed runoff change in the arid or semi-arid areas to climate variability and human activity on an annual scale. However, attribution results may differ greatly according to diffe ...
... ‘Core bacterial communities’, bacterial species that are found consistently throughout a river continuum, have previously been identified. However, variations in core and non-core bacterial community structure, as well as the relationships between these communities and water chemistry or geographic distance have not been well studied. Here, we sampled in the entire course of the Le'an River, China ...
Chiroptera; biomass; community structure; dry season; flowers; fruits; habitat fragmentation; habitat preferences; habitats; landscapes; nets (equipment); predation; primary productivity; rain forests; savannas; species abundance; species richness; understory; wet season; Amazonia
Abstract:
... The Amazon region is made up of a mosaic of important habitats scattered throughout the rainforests, which differ in vegetation structure, basal area, primary productivity, biomass and production of flowers and fruits. Consequently, species richness and abundance also vary between these habitat types, in part explaining the high levels of richness found in the Amazon region. Here, we sampled bats ...
... The water quality from rivers near to cities has decreased drastically over the decades due to the environmental pollution. The Ocoa River on its way through the Villavicencio city, Colombia, receives large volumes of domestic and industrial wastewater. In order to establish the effect of the contamination, biochemical and histopathology biomarkers were evaluated in the gills and the liver of two ...
... Medium‐ and large‐sized vertebrates play a key role in shaping overall forest functioning. Despite this, vertebrate interactions, from competition to mutualism, remain poorly studied, even though these interactions should be taken into account in our conservation and management strategies. Thus, we tackled the question of vertebrate co‐occurrence in tropical rainforests: Are (negative or positive) ...
... Mammals are known to vary in their sensitivity to urbanization. In heavily urbanized southern California, bobcats (Lynx rufus) prey on rabbits (Sylvilagus spp.) that forage for lush vegetation in developed areas. We collected data on the density of rabbits in adjacent urban and natural areas using visual line surveys. We also measured habitat use for seven GPS-collared female bobcats to determine ...
... Intermittent streams account for approximately one half of the global river network, and are especially common in arid and semi-arid regions. These systems are inhabited by several fish species that are adapted to their natural flow intermittency. While many fish species rely on permanent pools or perennial reaches to survive during the dry season, our knowledge regarding fish survival strategies ...
Soil and Water Assessment Tool model; data collection; dry season; prediction; statistical analysis; stream flow; temporal variation; uncertainty; water storage; watersheds; wet season; China
Abstract:
... The reservoir operation is a notable source of uncertainty in the natural streamflow and it should be represented in hydrological modelling to quantify the reservoir impact for more effective hydrological forecasting. While many researches focused on the effect of large reservoirs only, this study developed an online reservoir module where the small reservoirs were aggregated into one representati ...
Simone Simões Amaral; Maria Angélica Martins Costa; Turibio Gomes Soares Neto; Marillia Pereira Costa; Fabiana Ferrari Dias; Edson Anselmo; José Carlos dos Santos; João Andrade de Carvalho
United Nations Framework Convention on Climate Change; biomass; burning; carbon dioxide; carbon monoxide; deforestation; dry season; emissions; emissions factor; fires; forests; gases; greenhouse gases; methane; particulates; public policy; Amazonia; Brazil
Abstract:
... The rate of deforestation in Brazil increased by 29% between 2015 and 2016, resulting in an increase of greenhouse gas emissions (GHG) of 9%. Deforestation fires in the Amazonia are the main source of GHG in Brazil. In this work, amounts of CO2, CO, main hydrocarbon gases and PM2.5 emitted during deforestation fires, under real conditions directly in Brazilian Amazonia, were determined. A brief di ...
... Bakalin, V., Vilnet, A., Klimova, K. & Nguyen, V. S. 2019. Calypogeia vietnamica sp. nov. (Calypogeiaceae, Hepaticae) from North Vietnam and diversification in Calypogeia taxa with blue oil bodies. – Herzogia 32: 219 –229. Calypogeia vietnamica is described from the northern fringes of mountainous Indochina. The species belongs to the peculiar group of Calypogeia with blue oil bodies that is taxon ...
algorithms; arid lands; desertification; dry season; electrical conductivity; farming systems; lakes; land degradation; land restoration; least squares; models; monitoring; reflectance; remote sensing; salinity; satellites; semiarid zones; soil salinity; soil salinization; sustainable development; water quality; wet season; China
Abstract:
... Soil salinization is one of the most important causes for land degradation and desertification and is an important threat to land management, farming activities, water quality, and sustainable development in arid and semi-arid areas. Soil salinization is often characterized with significant spatiotemporal dynamics. The salt-affected soil is predominant in the Ebinur Lake region in the Northwestern ...
... The Mayaro virus disease (MAYVD) is an emerging mosquito borne zoonosis that was first reported on the island of Trinidad in 1954. The viral agent for this disease is known to presently be endemic to Central and South America. The enzootic cycle of the Mayaro virus (MAYV) is not fully characterized, though primates are thought to be the main reservoir with Haemagogus species of mosquitoes as the p ...
acid mine drainage; aquifers; cadmium; cobalt; copper; dry season; groundwater; heavy metals; iron; lead; manganese; mining; nickel; radionuclides; radon; river water; rivers; water pollution; wet season; zinc; China
Abstract:
... Groundwater discharge to river and the related heavy metal transportation were estimated for Dabaoshan, a mountain mining area where extensive mining activities had been conducted over 40 years. In the lower reach of the mining area, shallow aquifers were contaminated by varies heavy metals due to the discharge of acid mine drainage. Polluted aquifers act as long-term pollution sources to the surr ...
Guilherme Augusto Verola Mataveli; Maria Elisa Siqueira Silva; Daniela de Azeredo França; Nathaniel Alan Brunsell; Gabriel de Oliveira; Francielle da Silva Cardozo; Gabriel Bertani; Gabriel Pereira
anthropogenic activities; cerrado; data collection; dry season; ecosystems; emissions; land cover; moderate resolution imaging spectroradiometer; monitoring; particulates; remote sensing; savannas; wildfires; Brazil
Abstract:
... Fire occurrence is a major disturbance in the Brazilian Cerrado, which is driven by both natural and anthropogenic activities. Despite increasing efforts for monitoring the Cerrado, a biome-scale study for quantifying and understanding the variability of fire emissions is still needed. We aimed at characterizing and finding trends in Particulate Matter with diameter less than 2.5 µm (PM ...
breeding; cluster analysis; drinking water; dry season; metabolites; nonpoint source pollution; oxytetracycline; pollution control; pollution load; sewage; space and time; wastewater; Yangtze River
Abstract:
... The occurrence and spatio-temporal patterns of five tetracyclines (TCs) and six of their degradation products were investigated in twenty-eight drinking water sources along the lower Yangtze River (LYR) over dry, normal and flood seasons. Tetracycline (TC), oxytetracycline (OTC) and doxytetracycline (DXC) were the dominant antibiotics detected with the highest occurrence. The maximum concentration ...
Bowen ratio; aerodynamics; air quality; canopy; dry season; eddy covariance; energy flow; energy transfer; evapotranspiration; fallow; field experimentation; freshwater; latent heat flux; models; momentum; paddies; rice; skin temperature; soil temperature; vapor pressure deficit; wet season; India
Abstract:
... A field experiment was conducted in 2015 to study the land surface energy fluxes from tropical lowland rice paddy in eastern India with an objective to determine the mass, momentum, and energy exchange rates between rice paddies and the atmosphere. All the land surface energy fluxes were measured by eddy covariance (EC) system (make Campbell Scientific) in dry season (DS, 1–125 Julian days), dry f ...
... Many browse plants are undervalued due to insufficient knowledge about their potential feeding value. The study was conducted to evaluate the chemical composition, in vitro ruminal dry matter degradability (DRD) and dry matter intake of Melia azedarach, Leucaena leucocephala, Searsia lancea, Moringa oleifera and Acacia hebeclada. Matured leaves were collected and dried at room temperature and then ...
climate change; cropland; dry season; irrigated farming; irrigation; monitoring; rain; river flow; supply balance; time series analysis; water resources; water security; wet season; Brazil
Abstract:
... In Western Bahia, one of the most active agricultural frontiers of the world, cropland area and irrigated area are increasing at fast rates, and water conflicts have been happening at least since 2010. This study makes a hydroclimatic analysis of the water resources in Western Bahia, from both supply and demand viewpoints. Time series of precipitation for the period 1980–2015 and river disch ...
climate change; coastal plains; data collection; dry season; fire regime; fire season; fire severity; lightning; rain; seasonal variation; storms; wildfires; Southeastern United States
Abstract:
... Trends in average annual or seasonal precipitation are insufficient for detecting changes in the climatic fire season, especially in regions where the fire season is defined by wet–dry seasonal cycles and lightning activity. Using an extensive dataset (1897–2017) in the Coastal Plain of the southeastern United States, we examined changes in annual dry season length, total precipitation, and (since ...
Hevea brasiliensis; aboveground biomass; altitude; belowground biomass; carbon sequestration; carbon sinks; climate change; dry season; greenhouse gas emissions; humid tropics; income; land use change; landscapes; latex; models; plant density; plantations; planting; prediction; rubber; surveys; temperature; tree growth; trees; China
Abstract:
... Pará rubber (Hevea brasiliensis Müll. Arg) plantations have expanded into regions with sub-optimal growth conditions: distinct dry seasons and temperatures cooler than in humid tropics. The impact of these new marginal environments and future climate change on rubber tree development and latex yield is largely unknown. This hampers reliable prediction of farmers’ revenues and extent of carbon sequ ...
... The generation and transport of mineral dust is strongly related to climate on seasonal, year-to-year, and glacial-interglacial timescales. The modern dust cycle is influenced by soil moisture, which is partly a function of drought duration and severity. The production and transport of dust can therefore be amplified by global and regional droughts, thereby moderating ecosystem vulnerability to di ...
... In the Eastern Gangetic Plains (EGP) region of South Asia cropping systems are predominantly rice-based and comprise rice and non-rice crops (e.g. maize, wheat, lentil, mungbean, jute) in rotation. There are large gaps between potential crop yields and those achieved in farmers’ fields, primarily due to poor crop and soil management practices. Increasing climate variability and injudicious use of ...
... Mangroves are forest ecosystems located at the interface between land and sea where sediments presented a variety of contrasted environmental conditions (i.e. oxic/anoxic, non‐sulfidic/sulfidic, organic matter content) providing an ideal ecosystem to study microbial communities with niche differentiation and distinct community structures. In this work, prokaryotic and fungal compositions were inve ...
Acropora tenuis; acclimation; calcification; coastal water; corals; dry season; energy balance; light intensity; nutrients; photons; photosynthesis; reefs; rivers; sediments; water quality; wet season; Great Barrier Reef
Abstract:
... Coastal water quality and light attenuation can detrimentally affect coral health. This study investigated the effects of light limitation and reduced water quality on the physiological performance of the coral Acropora tenuis. Branches of individual colonies were collected in 2 m water depth at six inshore reefs at increasing distances from major river sources in the Great Barrier Reef, along a s ...
... Damage caused by invasive downey snow line mealybug, Rastrococcus iceryoides Green (Hemiptera: Pseudococcidae) has been reported to vary between 30% to complete crop loss where no control measure is applied. The current studies seek to determine factors influencing R. iceryoides population outbreaks, parasitoid – host and predator–prey relationships as well as predict optimal management strategies ...