Assessing rainfall variability, long-term trends, and drought incidences in the Tanzania part of the Kagera River sub-basin

Earth Science Informatics, Journal Year: 2025, Volume and Issue: 18(2)

Published: Jan. 17, 2025

Language: Английский

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Estimation of nutrient load in the wastes of Nile tilapia reared in cages and fed soybean meal-based diet supplemented with different levels of phytase enzyme

Cogent Food & Agriculture, Journal Year: 2025, Volume and Issue: 11(1)

Published: Feb. 16, 2025

With the rapidly increasing trend of cage fish farming in freshwater, practices to enhance sustainability are increasing. We estimated how different levels phytase enzyme (0, 500, 1000, 2000, 4000 FTU kg−1) affects growth performance and nutrient load tilapia (5.2 ± 0.1 g) reared 15 cages for 180 days. The experimental design followed a completely randomized approach, with three replicates. most significant increase was observed groups that were given diet supplemented at kg−1 feed. These reached slaughter size 420.2 6.6 g experienced weight gain approximately times greater than control group (final weight: 146.8 4.8 g). phosphorus nitrogen diets supplement feed 54% 32% lower, respectively, compared other phytase. Hence, it is advisable add concentration order improve availability nutrients, while also minimizing waste culture tilapia.

Language: Английский

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A Century of Water–Socioecological Dynamics and Evolutionary Stages in Lake Victoria Basin, East Africa

Land, Journal Year: 2025, Volume and Issue: 14(4), P. 906 - 906

Published: April 20, 2025

Understanding the feedback relationships and evolutionary stages of water–socioecological systems (W-SESs) is crucial for achieving sustainable development in basins. This study focuses on Lake Victoria Basin (LVB) East Africa, where population growth, rapid urbanization, developing industrialization have intensified water resource supply–demand conflicts, leading to socioecological issues such as environmental degradation ecological conflicts. The objective this research develop a theoretical framework W-SESs (LVB-WSESs) based SES framework, identify main drivers critical nodes evolution LVB-WSESs, analyze root causes water–society–ecology explore LVB-WSESs over past century. To achieve this, we employed an integrated qualitative quantitative analysis historical data combined with tipping point detection systematically assess dynamics LVB-WSESs. Our findings show that, under climate change (with 1 °C increase annual temperature since 1920s), growth (a six-fold economic development, land-use change, species invasion, basin’s demand resources, environments, aquatic ecosystems has continually increased, gradual imbalance functions. can be divided into five against backdrop societal transitions from colonial independent democratic systems: stable utilization period, slow period (1920s–1960s), (1960s–1990s), transition protection (1990s–2015), reconstruction equilibrium. not only enhances understanding long-term but also provides practical implications management similar basins globally. It enriches local practice global theories, providing new perspectives case references future watershed management. By identifying stages, our inform policy decisions interventions mitigate conflicts basin-level sustainability.

Language: Английский

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Understanding Possible Physical Mechanisms Associated With Variability of March to May Seasonal Extreme Wettest Days Rainfall in Tanzania

International Journal of Climatology, Journal Year: 2025, Volume and Issue: unknown

Published: April 29, 2025

ABSTRACT Extreme rainfall remains the most impactful natural disaster affecting environment and ecological system in Tanzania. Understanding possible physical mechanisms behind these events is crucial for mitigating associated risks. Therefore, interannual variability of extreme wettest days (EWDs) during March to May from 1981 2020 was examined using daily ground observations gridded data Climate Hazards Group InfraRed Precipitation with Station data. EWDs were determined by 99th percentile‐based method. The assessed empirical orthogonal function (EOF) wavelet methods. To understand their connectivity mechanisms, methods such as regression correlation applied analysis. Results show a significant increase under 95% confidence level, especially recent years, notable peak 2020, explaining 19.3% variance leading EOF1, which positively loaded across EOF1's principal component exhibits predominantly positive values, indicating close relationship between high regions EWDs. Wavelet analysis reveals oscillations at 2 5‐year intervals, linked climate phenomena like Indian Ocean Dipole El Niño‐Southern Oscillation. Climatologically, southwest‐oriented vertical integrated moisture flux (VIMF) vectors are predominant, moving westward over Tanzania due an anticyclonic southwestern Ocean. study concludes that EWD influenced convergence southerly westerly VIMF along Tanzania's coastal zone western Warming sea surface temperature anomalies various oceans (i.e., northwestern Atlantic Ocean, tropical northern Pacific Ocean) correlated These enhance or suppress creating low (upper) level (divergence) winds linking ascending (sinking) limb Walker‐type circulation (Pacific Atlantic)

Language: Английский

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Latest Pleistocene and Holocene primary producer communities and hydroclimate in Lake Victoria, eastern Africa

Quaternary Science Reviews, Journal Year: 2024, Volume and Issue: 330, P. 108599 - 108599

Published: March 16, 2024

The Lake Victoria ecosystem is emblematic of the catastrophic effects that human activities, particularly cultural eutrophication, can have on freshwater biodiversity. However, little known about long-term spatial and temporal pattern aquatic primary paleo-production (PPaq) producer communities in how these patterns relate to past climate variability, landscape evolution, lake hydrology, mixing regimes, nutrient cycling, biodiversity dynamics 17 kyr. We use sediments from four well-dated cores along a transect offshore nearshore sites, exploit XRF element scanning hyperspectral imaging data, TC, TN, bSi, δ13C δ15N, sedimentary pigments investigate paleolimnological variability change. Our findings demonstrate changes PPaq algal during kyr were closely related hydroclimatic changes, mixing, availability. During wetland phase (16.7–14.5 cal ka BP), levels remained generally low, while chromophytes chlorophytes dominated community. Following rapid level rise (∼14.2 BP) early African Humid Period (AHP), steadily increased, accompanied by shift towards cyanobacteria chromophytes. Holocene, our results suggest repeated short-lived arid intervals (∼10.5, ∼9, 7.8–7.2, ∼4, 3.2–3.0 two distinct periods enhanced associated with high diatom productivity: first one between 11 9 BP, which coincided maximum AHP (high precipitation, wind, mixing), second, less pronounced one, 7 4 BP. Between (i.e. 9–7 we observe reduced productivity, relatively low PPaq, C/N ratios, suggesting conditions more stable stratification, likely wind strength, some limitation (N P). Finally, drier around end (ca. late Holocene decreasing increasing dominance cyanobacteria. Given reconstruction over kyr, conclude 20th century are unprecedentedly high, consistent massive human-mediated impact including loss.

Language: Английский

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Sediment and soil source apportionment using geochemical fingerprinting techniques in the Winam Gulf, Lake Victoria

CATENA, Journal Year: 2025, Volume and Issue: 255, P. 109053 - 109053

Published: April 18, 2025

Language: Английский

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Socioeconomic consequences of cyanobacterial harmful algal blooms in small-scale fishing communities of Winam Gulf, Lake Victoria

Journal of Great Lakes Research, Journal Year: 2023, Volume and Issue: 50(5), P. 102236 - 102236

Published: Sept. 30, 2023

Language: Английский

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Future success and ways forward for scientific approaches on the African Great Lakes

Journal of Great Lakes Research, Journal Year: 2023, Volume and Issue: 49(6), P. 102242 - 102242

Published: Nov. 4, 2023

The seven African Great Lakes are some of the most critical freshwater, large-lake systems in world, providing essential services, food, drinking water, and other livelihood support to over 62 million people. Like freshwater around these lakes strained by anthropogenic stressors, leading degradation biologically important, human-dependent resources. Despite their importance, suffer from insufficient research approaches which short-term, disparate, unharmonized. Further, a lack monitoring, data information exchange, education training, gender balance research, all lead knowledge on better manage protect lakes. While past efforts have resulted accumulation, there is need for new understanding managing lakes: bottom-up, harmonized, long-term processes. This paper, those within this special section Journal Research, highlight new, highly collaborative experts representing each riparian country Lake through formal advisory groups. These papers result harmonized collegial agreements as what issues be addressed foremost, written ground. lake has specific, prioritized lists issues, five overarching must achieve success agency coordination scientists; increase monitoring; strengthen training existing future experts; enhance exchange; ensure stronger science leadership positions.

Language: Английский

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Temporal trends of water quality parameters, heavy metals, microplastics, and emerging organic pollutants in Lake Victoria and its basin: knowns, knowledge gaps, and future directions

Environmental Nanotechnology Monitoring & Management, Journal Year: 2024, Volume and Issue: 22, P. 100962 - 100962

Published: May 10, 2024

Language: Английский

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Introduction to the special section: Aquatic resources for a sustainable future and blue economy prosperity for the African Great Lakes region

Journal of Great Lakes Research, Journal Year: 2024, Volume and Issue: 50(5), P. 102413 - 102413

Published: Aug. 5, 2024

Climate change, overfishing, pollution, and habitat degradation are no longer distant threats demand our collective action. Rising to this challenge, the Aquatic Resources Blue Economy Conference (ARBEC) held in Kisumu, Kenya served as a call action for sustainable aquatic practices protection of blue economy resources. The holds much promise yet global community faces unprecedented environmental challenges, it's potential hinges on ability make informed, science-driven decisions.

Language: Английский

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