Flooded Soil Research Articles

Mitigation of Paddy Field Soil Methane Emissions by Betaproteobacterium <i>Azoarcus</i> Inoculation of Rice Seeds

Paddy fields are a major source of atmospheric methane, a greenhouse gas produced by methanogens and consumed by methanotrophs in flooded soil. The inoculation of rice seeds with the bacterium Azoarcus sp. KH32C alters the rice root-associated soil bacterial community composition. The present study investigated the effects of KH32C-inoculated rice cultivation on soil methanogens and methanotrophs involved in methane emissions from a rice paddy field. KH32C-inoculated and non-inoculated rice (cv. Nipponbare) were cultivated in a Japanese rice paddy with and without nitrogen fertilizer. Measurements of methane emissions and soil solution chemical properties revealed increases in methane flux over the waterlogged period with elevations in the concentrations of dissolved methane, dissolved organic carbon, and ferrous iron, which is an indicator of soil reduction levels. Reverse transcription quantitative PCR and amplicon sequencing were used to assess the transcription of the methyl-coenzyme M reductase gene (mcrA) from methanogens and the particulate methane monooxygenase gene (pmoA) from methanotrophs in paddy soil. The results obtained showed not only the transcript copy numbers, but also the compositions of mcrA and pmoA transcripts were related to methane flux. KH32C-inoculated rice cultivation recruited soil methanogens and methanotrophs that suppressed high methane synthesis, increased methane consumption, and decreased methane emissions by 23.5 and 17.2% under non-fertilized and nitrogen-fertilized conditions, respectively, while maintaining rice grain yield. The present study demonstrated the mitigation of paddy field methane emissions arising from the use of KH32C in rice cultivation due to its influence on the compositions of soil methanogen and methanotroph populations.

Alum Reduced Phosphorus Release from Flooded Soils Under Cold Spring Weather Conditions

Alum Reduced Phosphorus Release from Flooded Soils Under Cold Spring Weather Conditions

Flooding-induced inorganic phosphorus transformations in two soils, with and without gypsum amendment.

Anaerobic conditions developed during flooding can increase phosphorus (P) losses from soils to waterways. Soil amendment with gypsum (CaSO4 ·2H2 O) can effectively reduce flooding-induced P release, but its effectiveness is soil dependent, and the reasons are poorly understood. The objectives of this study were to reveal the possible inorganic P transformations during flooding of two soils (acidic-Neuenberg sandy loam [NBG-SL] and alkaline-Fyala clay [FYL-Cl]), with and without gypsum amendment prior to flooding. Porewater samples collected at 0, 35, and 70 d after flooding (DAF) from soils incubated in vessels were analyzed for dissolved reactive P (DRP); pH; and concentrations of calcium (Ca), magnesium, iron (Fe), manganese, chloride, nitrate, sulfate, and fluoride. Thermodynamic modeling using Visual MINTEQ software and chemical fractionation of soil P were used to infer P transformations. Soil redox potential (Eh) decreased with flooding and favored reductive dissolution of Fe-associated P increasing porewater DRP concentrations. Greater solubility of Ca-P under acidic pH maintained a higher DRP concentration in NBG-SL during early stages of flooding. A subsequent increase in pH with flooding and higher Ca concentration with added gypsum enhanced the stability of Ca-P (β-tricalcium phosphate and octacalcium phosphate), reducing the DRP concentration in gypsum-amended NBG-SL. Stability of Ca-P was less affected with flooding and gypsum amendment in FYL-Cl soil because it had an alkaline pH and inherently higher Ca concentration. The FYL-Cl, with a more rapid decrease in Eh than NBG-SL, became severely reduced, releasing more P and Fe by 70 DAF. These conditions favored vivianite formation in FYL-Cl but not in NBG-SL.

The impact of the development of negative soil processes on the land fund of the Russian Federation

One of the reasons of the reduction of agricultural land is the degradation of soil processes. The main negative processes occurring in soils and leading to their degradation are erosion (water and wind), reduction of humus content in the soil. A significant spread of negative processes developing due to the action of natural and anthropogenic factors leads to a critical decrease in soil fertility. By washing away the upper fertile soil layer and the formation of large gullies due to improper tillage, soil erosion is formed. In order to prevent soil erosion, it is necessary to take measures to prevent an increase in the area of degraded land. The article considers the impact of negative processes, such as water and wind erosion, salinization, overwetting, flooding and waterlogging of soils, etc. on the land fund.

Longue Durée

New approaches to combine flood protection, soil regeneration and water management strategies with urban design, landscape architecture and spatial planning in delta regions cannot do without knowledge and understanding of history. To find a new balance between urbanization, climate change, geopolitical shifts, the energy transition in deltas it is crucial to understand the evaluation of the system from the past to what it is today and can be in the future. The logic of the relationship between design, engineering, science and governance on the one hand, and the logic with the natural system on the other, determined the current conditions and its performance. In the development of cities, at any time, there is the concept of Longue Durée recognizing the formative forces of nature and the relevance of historic concepts to take into account (Braudel, 1949). The main question of this issue is: How can interdisciplinary approaches of design, engineering, science and governance respond to the environmental crisis and steer upon the Longue Durée of the delta?

Biochar Addition in Flooded Paddy Soil for Ameliorating the Effects of Elevated Carbon dioxide (eCO2)

Improving soil organic carbon by biochar application is of concern in flooded rice soils. However, the effect of biochar on soil physico-chemical and biological properties under increasing levels of CO2 is limited and needs investigation. The present study examined the response of soil carbon pool, and soil enzyme activities of rice upon application of biochar under elevated carbon dioxide (eCO2) - 55030 μmol.mol−1 level. The study was carried out in open-top chambers (OTC) under a rice-rice (Oryza sativa L.) cropping system in 2020. A set of OTCs at ambient CO2 (415 ± 10 μmol mol−1 (aCO2)) served as a check with and without biochar application. The fourth OTC maintained eCO2 without the application of biochar. Rhizosphere soil samples from three critical crop stages viz., active tillering, flowering, and maturity were analyzed for various physico- chemical and biological properties. Most soil biological parameters, specifically soil enzymes, β – glucosidase, urease, and phosphatases, exhibited significant changes during the flowering stage in biochar applied e(CO2) treatment. The per cent increase of 46.8 %, 30.2 %, 18.75 %, and 51.2 % over ambient CO2 in soil organic carbon (SOC), soil microbial biomass carbon (SMBC), oxidizable carbon (OC), and water-soluble carbon, respectively, was observed. This study emphasized that biochar can improve the soil C pool and enzyme activities under anticipated climate change.

Dam impoundment elevates soil phosphorus and some trace elements in reservoir hydro‐fluctuation belts

AbstractTo examine the role of dam impoundment in elevating the levels of soil‐associated phosphorus (P) and trace elements in reservoir hydro‐fluctuation belts (RHB), soil samples in RHB and adjacent uplands (non‐flooded area, NFA) in the Three Gorges Reservoir, China, were collected and analyzed. Concentrations of available P, copper (Cu), chromium (Cr), and zinc (Zn) were found to be higher in RHB than in NFA (p < .05), whereas organic carbon was comparable in RHB and NFA (p > .05). The elevated levels of Cu, Cr, and Zn in RHB were probably associated the repeated drying–rewetting cycles created by the dam impoundment. The 95th percentile of the single‐factor pollution index and geo‐accumulation index in RHB were 1.29 and −0.21 for Zn, 3.21 and 1.15 for Cu and 3.37 and 1.17 for Cr. Elevated pollution potential of soil‐associated Zn, Cu, and Cr existed in RHB of the Three Gorges Reservoir.Core Ideas Dam impoundments decreased total C and total N concentrations in reservoir flooded soils. Cu, Zn, and Cr concentrated in the reservoir flood areas. Variability of Cu, Zn, and Cr was captured in single‐factor pollution index and geo‐accumulation index

RESISTÊNCIA DO SOLO E ANÁLISES MULTIVARIADAS COMO UM MÉTODO A UXILIAR PARA A SELEÇÃO DE PROGÊNIES DE Calophyllum brasiliense

ABSTRACT Precision silviculture is being developed to manage and improve Calophyllum brasiliense, a tree species associated with wet and swampy soils. This study estimated genetic parameters for growth traits in response to soil resistance as an auxiliary tool for identifying and selecting progenies adapted to water-saturated soils. This was undertaken in a progeny test of C. brasiliense in which 1,200 seedlings grown from seeds collected from a natural population were planted in a randomized complete block design for single-tree plots. Genetic statistical analysis was conducted using the REML/BLUP method. Significant differences (p<0.01) in diameter at breast height were observed among the progenies. The coefficients of genetic variation and heritability at the individual and progeny levels were low for diameter at breast height and height, indicating low genetic control for these traits, while high positive and significant genetic and phenotypic correlations were detected between diameter at breast height and height. Theoretical genetic gains and multivariate statistical analysis indicated three groups of progenies with different degrees of tolerance and adaptability to flooded soils, which could be useful in future breeding programs for this species, although further analysis at advanced ages is still required. The mean heights of tolerant and sensitive progenies were 12 and 58%, respectively, lower than the theoretical values, indicating that constant soil flooding is harmful to this species.

PECULIARITY OF SOIL COVER FORMATION IN THE UPPER PART OF THE KANIV RESERVOIR

The problem of water reservoirs, their role and positive and negative effects on the environment has become extremely acute around the world. The issue of the impact of reservoirs on soils has been studied for a long time. The greatest attention was paid to the soils erosion on the coasts, especially those composed of loamy rocks. Flooding of lands and waterlogging of soils in humid regions and salinization of flooded soils in arid regions have been widely studied. There was a need to study the features of litho-morphogenesis and soil formation on the islands (residual and newly formed) and the coast of these reservoirs during the study of the Dnieper reservoirs. There is also a need to study successions of terrestrial and aquatic vegetation, as reservoirs are rapidly overgrown, reducing their water permeability. The research methods are land and water routes on the islands and reservoir coasts, standard methods of description and analysis of soil morphology and mapping of their distribution. The locations of soil profile were recorded with a GARMIN GPS receiver. Dynamics of hydromorphic landscapes in time and space on the islands were studied using Landsat and Sentinel satellites remote sensing data of Earth. Hydrological and morphological conditions and dynamics of vegetation cover as factors in the formation of the soil cover of the islands and reservoir coast were considered. It was done in order to assess the peculiarities of their profile, properties and recreational and economic value. It was established that the upper (river) part of the reservoir is dominated by soddy soils of varying degrees of gleyey, as well as meadow, meadow-swamp, and marsh soils. The formation of soils as the biotope basis of hydromorphic landscapes occurs differently on the "frontal" (mainly northern) part of the islands and on their rear (southern) part in accordance with the hydromorphological features and laws of litho-morphogenesis. Research is provided by the community with the Czech Institute "CzechGlobe" and has the further perspective of a scientific project of international scale.

Tolerance of Ormosia arborea (Fabaceae) seed to water submersion

Abstract Soil flooding restricts the availability of the oxygen necessary to activate the embryonic physiological processes that characterize seed germination. However, some species have adaptations that allow them to grow naturally in areas prone to flooding, such as Ormosia arborea, a native species of the Atlantic forest and the Cerrado. The objective of this work was to evaluate how seed germination and emergence in this species were affected by submersion in water and scarification. In experiment 1, the seeds were scarified by 15 minutes in sulfuric acid and was subsequently sown in tubes submerged in water for 0, 15, 30 and 45 days. In experiments 2 and 3, seeds were submerged in running water for the same period and, after each time of submersion, were scarified by 0, 5, 10 and 15 minutes in sulfuric acid and sown either in tubes and in Germitest® paper. It was found that, after breaking the tegumental dormancy, 15 days of flooding is enough to derail the germination of O. arborea seeds that tolerate submersion in water when they are intact. This response indicates that the hard, impermeable seed coat is an important seed characteristic for this response.

Phytoremediation potential evaluation of multiple Salix clones for heavy metals (Cd, Zn and Pb) in flooded soils

Climate-induced flooding makes soil more vulnerable to heavy metal contamination, posing challenges for soil remediation. Salix has the potential to cope with flooding stress and environmental contamination, but its effectiveness in flooded soils with multiple heavy metals has not yet been well assessed. Thus, the present work tested fifteen Salix clones grown in multimetal (Cd, Zn and Pb) contaminated soils under non-flooded versus flooded conditions. The results indicated that all tested Salix clones withstood long-term (90 d) flooding. Compared to the non-flooded condition, the flooded condition reduced the Cd (11.7–90.1%) contents in all organs but dramatically increased the Zn and Pb contents in the roots. The bioconcentration factor values of heavy metals in the aboveground organs were in the order of Cd > Zn > Pb. The tested Salix clones were characterized by high phytoextraction capacity for Cd and Zn under non-flooded condition and phytostabilization trait for Pb under flooded condition. To assess the overall performance of phytoremediation potentials, we attempted to use an analytic hierarchy process-entropy weight (AHP-EW) model, which considered the growth performance, photosynthetic parameters, accumulation, and mobility of toxic metals. Three Salix clones (J1010, P54 and P667) exhibited significant potential for multimetal remediation capacities. The current study provided valuable insights into the phytomanagement of woody plants, and the AHP-EW model is helpful for screening suitable trees for the phytoremediation of heavily multimetal contaminated wetlands.

Improvement of the submergence stress tolerance of local South Sumatran rice through the introgression of the Sub1 gene by using marker-assisted selection

Submergence stress due to unpredictable soil flooding is one of the main constraints encountered in rainfed growing areas, especially in Southern Sumatran riparian swamps. The development of submergence-stress-tolerant cultivars through the introgression of Sub1 via marker-assisted backcrossing (MABC) is an ideal solution. This study was carried out during 2020 at Sriwijaya University, Palembang, Indonesia, with the aim to select Sub1-introgressed lines in BC3F1 generations on the basis of MABC and to screen out the SSR markers that were unlinked to the target gene for application in subsequent background selection studies. Results revealed that almost all the backcrossed progenies segregated from the rice parental cultivars ‘FR13A’ and ‘Pegagan’. The backcrossed lines showed significantly improved submergence stress tolerance and recovery rates compared with their parents. Sub1 introgression into the BC3F1 generation was confirmed by the tightly linked Sub1 marker SUB1C173, and marker RM23915 was used for recombinant selection. These markers followed the expected marker segregation ratio in accordance with the Mendelian single gene model. In the parental polymorphism survey, 84 out of 237 SSR markers that were unlinked to the target loci were found to be available for background study. Twenty-seven backcrossed lines were selected on the basis of foreground selection. Seven plants were selected on the basis of the recombinant marker RM23915. Five backcrossed lines were further selected on the basis of submergence stress tolerance and agronomic performance.

Acaulospora as the Dominant Arbuscular Mycorrhizal Fungi in Organic Lowland Rice Paddies Improves Phosphorus Availability in Soils

Flooding in rainfed lowlands greatly impairs the mutualistic relationship between indigenous arbuscular mycorrhizal fungi (AMF) and rice. In flooded soils, root colonization by AMF is arrested, but some AMF genera, defined as the core AMF, remain present. However, the core AMF in rainfed lowlands and their symbiotic roles remain unknown. Here, we showed that Acaulospora fungi were the core AMF in rice seedling roots of the Sangyod Muang Phatthalung (SMP) landrace rice variety grown in non-flooded and flooded paddy soils. Subsequently, indigenous Acaulospora spores were propagated by trap cultures using maize as the host plants. Therefore, to clarify the roles of cultured Acaulospora spores in a symbiotic partnership, the model japonica rice variety Nipponbare was grown in sterile soil inoculated with Acaulospora spores, and recolonized with a native microbial filtrate from the organic rice paddy soil. Our data demonstrated that the inoculation of Acaulospora spores in well-drained soil under a nutrient-sufficient condition for six weeks enabled 70 percent of the rice roots to be colonized by the fungi, leading to higher phosphate (Pi) accumulation in the mycorrhizal roots. Unexpectedly, the growth of rice seedlings was significantly suppressed by inoculation while photosynthetic parameters such as fractions of incoming light energy and relative chlorophyll content were unaltered. In the soil, the Acaulospora fungi increased soil phosphorus (P) availability by enhancing the secretion of acid phosphatase in the mycorrhizal roots. The findings of this work elucidate the symbiotic roles of the dominant Acaulospora fungi from lowland rice paddies.

Fractionation of stable carbon isotopes during acetate consumption by methanogenic and sulfidogenic microbial communities in rice paddy soils and lake sediments

Abstract. Acetate is an important intermediate during the degradation of organic matter in anoxic flooded soils and sediments. Acetate is disproportionated to CH4 and CO2 by methanogenic or is oxidized to CO2 by sulfate-reducing microorganisms. These reactions result in carbon isotope fractionation, depending on the microbial species and their particular carbon metabolism. To learn more about the magnitude of the isotopic enrichment factors (ε) involved, acetate conversion to CH4 and CO2 was measured in anoxic paddy soils from Vercelli (Italy) and the International Rice Research Institute (IRRI, the Philippines) and in anoxic lake sediments from the northeastern and the southwestern basins of Lake Fuchskuhle (Germany). Acetate consumption was measured using samples of paddy soil or lake sediment suspended in water or in phosphate buffer (pH 7.0), both in the absence and presence of sulfate (gypsum), and of methyl fluoride (CH3F), an inhibitor of aceticlastic methanogenesis. Under methanogenic conditions, values of εac for acetate consumption were always in a range of −21 ‰ to −17 ‰ but higher in the lake sediment from the southwestern basin (−11 ‰). Under sulfidogenic conditions εac values tended to be slightly lower (−26 ‰ to −19 ‰), especially when aceticlastic methanogenesis was inhibited. Again, εac in the lake sediment of the southwestern basin was higher (−18 ‰ to −14 ‰). Determination of εCH4 from the accumulation of 13C in CH4 resulted in much lower values (−37 ‰ to −27 ‰) than from the depletion of 13C in acetate (−21 ‰ to −17 ‰ ), especially when acetate degradation was measured in buffer suspensions. The microbial communities were characterized by sequencing the bacterial 16S rRNA (ribosomal ribonucleic acid) genes as well as the methanogenic mcrA and sulfidogenic dsrB genes. The microbial communities were quite different between lake sediments and paddy soils but were similar in the sediments of the two lake basins and in the soils from Vercelli and the IRRI, and they were similar after preincubation without and with addition of sulfate (gypsum). The different microbial compositions could hardly serve for the prediction of the magnitude of enrichment factors.

Flood Hazard Zonation Using an Artificial Neural Network Model: A Case Study of Kabul River Basin, Pakistan

Floods are the most frequent and destructive natural disasters causing damages to human lives and their properties every year around the world. Pakistan in general and the Peshawar Vale, in particular, is vulnerable to recurrent floods due to its unique physiography. Peshawar Vale is drained by River Kabul and its major tributaries namely, River Swat, River Jindi, River Kalpani, River Budhni and River Bara. Kabul River has a length of approximately 700 km, out of which 560 km is in Afghanistan and the rest falls in Pakistan. Looking at the physiography and prevailing flood characteristics, the development of a flood hazard model is required to provide feedback to decision-makers for the sustainability of the livelihoods of the inhabitants. Peshawar Vale is a flood-prone area, where recurrent flood events have caused damages to standing crops, agricultural land, sources of livelihood earnings and infrastructure. The objective of this study was to determine the effectiveness of the ANN algorithm in the determination of flood inundated areas. The ANN algorithm was implemented in C# for the prediction of inundated areas using nine flood causative factors, that is, drainage network, river discharge, rainfall, slope, flow accumulation, soil, surface geology, flood depth and land use. For the preparation of spatial geodatabases, thematic layers of the drainage network, river discharge, rainfall, slope, flow accumulation, soil, surface geology, flood depth and land use were generated in the GIS environment. A Neural Network of nine, six and one neurons for the first, second and output layers, respectively, were designed and subsequently developed. The output and the resultant product of the Neural Network approach include flood hazard mapping and zonation of the study area. Parallel to this, the performance of the model was evaluated using Root Mean Square Error (RMSE) and Correlation coefficient (R2). This study has further highlighted the applicability and capability of the ANN in flood hazard mapping and zonation. The analysis revealed that the proposed model is an effective and viable approach for flood hazard analysis and zonation.

Drought and Subsequent Soil Flooding Affect the Growth and Metabolism of Savoy Cabbage.

An important factor of current climate change is water availability, with both droughts and flooding becoming more frequent. Effects of individual stresses on plant traits are well studied, although less is known about the impacts of sequences of different stresses. We used savoy cabbage to study the consequences of control conditions (well-watered) versus continuous drought versus drought followed by soil flooding and a potential recovery phase on shoot growth and leaf metabolism. Under continuous drought, plants produced less than half of the shoot biomass compared to controls, but had a >20% higher water use efficiency. In the soil flooding treatment, plants exhibited the poorest growth performance, particularly after the “recovery” phase. The carbon-to-nitrogen ratio was at least twice as high, whereas amino acid concentrations were lowest in leaves of controls compared to stressed plants. Some glucosinolates, characteristic metabolites of Brassicales, showed lower concentrations, especially in plants of the flooding treatment. Stress-specific investment into different amino acids, many of them acting as osmolytes, as well as glucosinolates, indicate that these metabolites play distinct roles in the responses of plants to different water availability conditions. To reduce losses in crop production, we need to understand plant responses to dynamic climate change scenarios.

Effects of drying and simulated flooding on soil phosphorus dynamics from two contrasting UK grassland soils

AbstractFlooding is known to mobilise soil phosphorus (P). However, it is still not clear how climate change‐driven extended periods of soil drying followed by flooding will affect soil‐P dynamics. We tested the hypothesis under laboratory conditions that soil antecedent conditions (moist/dry) determine the amount of P mobilised upon flooding. A series of controlled laboratory experiments were carried out by flooding samples of two contrasting soils (a Dystric Cambisol [Crediton series] and a Stagni‐Vertic Cambisol [Hallsworth series]), which had each been either dried (40°C for 10 days) or kept at field moisture conditions (25% moisture content). Flooding was simulated by maintaining a 10‐cm water column depth in mesocosms. Periodically collected water samples were analysed for dissolved reactive P (DRP), total dissolved P (TDP) and dissolved unreactive P (DUP). The onset of flooding significantly (p < 0.001) increased dissolved concentrations of all forms of P. The release of TDP coincided with a reduction in redox potential, suggesting reductive dissolution of P bearing iron/manganese (Fe/Mn) minerals as indicated by a significant positive correlation between TDP and dissolved Fe (r = 0.430, p < 0.001) and TDP and dissolved Mn (r = 0.622, p < 0.001). Flooding of the dried soils caused a significantly greater increase in the dissolved P concentrations of all forms of P relative to their moist‐flooded counterparts. This could be due to a combination of factors which are associated with soil drying and flooding. The Crediton dry‐flooded soils released higher concentrations of DRP upon flooding (e.g. 0.14 mg P L−1 on day 1 after flooding) perhaps due to its higher concentrations of water‐ and NaHCO3‐extractable P than the Hallsworth dry‐flooded (HDF) soil (0.03 mg P L−1 on day 1 after flooding). However, most of the P in the water column of the dry‐flooded soils was unreactive, with the HDF soil releasing higher concentrations of DUP, likely due to its higher organic matter and microbial biomass P contents. The results suggest that flooding of dried soils has greater potential to enhance mobilisation of soil‐P than flooding of moist soils and thus has potential implications for soil fertility and surface water quality.Highlights Flooding significantly increased dissolved concentrations of all forms of P. Dried soils released much greater P than their moist counterparts upon flooding. Increased amounts of P in the floodwater coincided with reductions in redox potential and biomass P. Soil with greater amount of biomass‐P and organic matter released greater amounts of dissolved unreactive P.

Changes in biomass burning, wetland extent, or agriculture drive atmospheric NH<sub>3</sub> trends in select African regions

Abstract. Atmospheric ammonia (NH3) is a precursor to fine particulate matter and a source of nitrogen (N) deposition that can adversely affect ecosystem health. The main sources of NH3 – agriculture and biomass burning – are undergoing are or expected to undergo substantial changes in Africa. Although evidence of increasing NH3 over parts of Africa has been observed, the mechanisms behind these trends are not well understood. Here we use observations of atmospheric NH3 vertical column densities (VCDs) from the Infrared Atmospheric Sounding Interferometer (IASI) along with other satellite observations of the land surface and atmosphere to evaluate how NH3 concentrations have changed over Africa from 2008 through 2018, and what has caused those changes. In West Africa NH3 VCDs are observed to increase during the late dry season, with increases of over 6 % yr−1 in Nigeria during February and March (p<0.01). These positive trends are associated with increasing burned area and CO trends during these months, likely related to agricultural preparation. Increases are also observed in the Lake Victoria basin region, where they are associated with expanding agricultural area. In contrast, NH3 VCDs declined over the Sudd wetlands in South Sudan by over 1.5 % yr−1, though not significantly (p=0.28). Annual maxima in NH3 VCDs in South Sudan occur during February through May and are associated with the drying of temporarily flooded wetland soils, which favor emissions of NH3. The change in mean NH3 VCDs over the Sudd is strongly correlated with variation in wetland extent in the Sudd: in years when more area remained flooded during the dry season, NH3 VCDs were lower (r=0.64, p<0.05). Relationships between biomass burning and NH3 may be observed when evaluating national-scale statistics: countries with the highest rates of increasing NH3 VCDs also had high rates of growth in CO VCDs; burned area displayed a similar pattern, though not significantly. Livestock numbers were also higher in countries with intermediate or high rates of NH3 VCD growth. Fertilizer use in Africa is currently low but growing; implementing practices that can limit NH3 losses from fertilizer as agriculture is intensified may help mitigate impacts on health and ecosystems.

Assessment of NEWMAP Effects on Gully Erosion Control and Environmental Development over South East, Nigeria

The potential impacts of gully erosion over South Eastern Nigeria are a worrisome scenario. It has resulted in the displacement of millions of habitats, agricultural, and economic losses. The result of the effect of Nigerian Erosion Watershed Management Project (NEWMAP) monitoring and evaluation on the effect of gully erosion on economic development in this study has revealed a positive significant influence at P < 0.05 over the study region. Also, it is revealed that NEWMAP programmes have significantly covered some constructions of hydraulic structures for flood routing and soil erosion control in South East, Nigeria. This intervention has significantly reduced the rate of land degradation occasioned by soil erosion, protection of watershed and agricultural land, which has thus been responsible for improved agricultural production. In conclusion, it is imperative to conduct periodic monitoring and evaluation of the activities of NEWMAP to building a strong evidence-based mechanism that enhances assessment of the diverse range of intervention projects on the dwellers of South-East extraction.

Assessment of NEWMAP Effects on Gully Erosion Control and Environmental Development over South East, Nigeria

The potential impacts of gully erosion over South Eastern Nigeria are a worrisome scenario. It has resulted in the displacement of millions of habitats, agricultural, and economic losses. The result of the effect of Nigerian Erosion Watershed Management Project (NEWMAP) monitoring and evaluation on the effect of gully erosion on economic development in this study has revealed a positive significant influence at P < 0.05 over the study region. Also, it is revealed that NEWMAP programmes have significantly covered some constructions of hydraulic structures for flood routing and soil erosion control in South East, Nigeria. This intervention has significantly reduced the rate of land degradation occasioned by soil erosion, protection of watershed and agricultural land, which has thus been responsible for improved agricultural production. In conclusion, it is imperative to conduct periodic monitoring and evaluation of the activities of NEWMAP to building a strong evidence-based mechanism that enhances assessment of the diverse range of intervention projects on the dwellers of South-East extraction.