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Seasonal river connections modulate community structure in (sub) tropical temporary pools
(Elservier, 2025-12-01) Mwaijengo, Grite; Vanschoenwinkel, Bram; Brendonck, Luc
In natural river systems in arid and semi-arid lands, surrounding floodplains may contain
temporary pools. Some of these may be mainly rain-filled (endorheic systems) while others may
be partly rain-fed but connect to the flooding river during a good rainy season (river-connected
pools). However, how seasonal river flooding affects the community structure in temporary
floodplain pools is not well understood, particularly in the Afro-tropical region. Here, we studied
the role of seasonal river connections in modulating water quality and benthic macroinvertebrate
community structure and functional feeding groups in a set of endorheic versus river-connected
temporary pools in a river-floodplain ecosystem in northeastern Tanzania. Benthic
macroinvertebrate communities from the two habitats were significantly differentiated. Spatial
species turnover (β-diversity) was higher in river-connected pools, but endorheic ones supported
a higher taxon richness (alpha diversity). Benthic macroinvertebrate community dissimilarity
between pools was largely determined by turnover rather than by nestedness. Hydrological
connectivity was positively associated with electric conductivity and negatively associated with
nutrient concentrations in the river-connected pools. In addition, the river facilitated fish dispersal,
which likely excluded predation sensitive taxa such as the large branchiopod crustaceans
Streptocephalus bourquinii and Streptocephalus wirminghausi. Taxon richness of collector-
gatherers and scrapers was significantly different between pool types. Indicator species analysis
revealed no specific fauna unique to river-connected pools. This study illustrates that land
management schemes that aim to preserve temporary-pool biodiversity should strive to include
both endorheic and river-connected pools to support high regional biodiversity, potentially with a
priority for the more diverse endorheic systems
Understanding farmer knowledge, practices and decision-making in pest and disease management: the case of Irish potato (Solanum tuberosum) cultivation in Mbeya, Tanzania
(Discover Agriculture, 2025-11-27) Laizer, Hudson
rish potato (Solanum tuberosum) is an important food and cash crop for smallholder
farmers in Tanzania, particularly in the Southern Highlands. Despite these, yields
remain low due to persistent challenges from pests and diseases, threatening both
productivity and household incomes. This study examined knowledge, perceptions
and practices of smallholder farmers in managing pests and diseases of Irish potato
in Mbeya, Tanzania. A total of 225 farmers from five wards were surveyed using
structured interviews and focus group discussions. Most respondents (83%) identified
pests and 73% identified diseases as major constraints. Aphids (83%), whiteflies
(71%) and potato tuber moth (39%) were the most commonly reported pests, while
early blight (91%), late blight (45%) and Fusarium wilt (29%) were the most cited
diseases. Despite the widespread use of chemical pesticides (92%) and fungicides
(72%), access to these inputs was constrained by high costs, limited availability and
insufficient knowledge, with only 24% of farmers reporting effective use. Non-
chemical methods, such as crop rotation, intercropping and botanical extracts,
were rarely practiced, reflecting low awareness and limited extension support. Most
farmers relied on experience rather than consulting agricultural officers, and over
90% used traditional seed varieties. Yields varied significantly among wards, with
averages ranging from 1.1 to 22.4 t/ha. While farmers demonstrated awareness of
pests and diseases, management practices were heavily dependent on synthetic
chemicals, with minimal integration of sustainable strategies. These findings highlight
the need to promote integrated pest and disease management approaches tailored
to local conditions for improving productivity of Irish potato.
Enhanced Hydrogenation of Cyclohexanone: A Multi‐ Scale Investigation Into Noncatalytic and Catalytic Pathways Towards Sustainable Conversion
(Society of Chemical Industry and John Wiley & Sons Ltd, 2025-11-14) Kariim, Ishaq; Park, Ji‐Yeon; Swai, Hulda; Kivevele, Thomas; Lee, In‐Gu
The selective hydrogenation of oxygenated compounds is crucial for the conversion of biocrude into platform chemicals. However, the
presence of stable oxygenated species, cyclohexanone, in biocrude limits possess a challenge for easy conversion process. This study
aims to investigate both Noncatalytic and catalytic hydrogenation of cyclohexanone as a model compound to understand its trans-
formation pathways. Monometallic and trimetallic catalysts supported of biochar were developed using impregnation method and
characterized via SEM‐EDS, FTIR, BET, NH3‐TPD, XPS and TEM to correlate structural features with catalytic performance. In
supercritical ethanol condition at 350°C, Zn‐supported biochar promoted aromatization (4.65 area%), Ce‐supported biochar achieved
the highest ketone conversion (83.20 area%), and Ni‐supported biochar exhibited the highest hydrocarbon selectivity (18.27 area%). The
performance of Ni and Ce during the hydrogenation of cyclohexanone model compound resulted in the development of NiCeMo‐
biochar catalyst for the application towards the upgrading of real‐life biocrude. The NiCeMo catalyst depicts the presence of Ni2+
, Ce3+
/
Ce4+ and Mo4+
/Mo6+ which promotes the hydrogen generation and activation and the formation of oxygen vacancy. The catalyst
showed optimal performance at 350°C and 2 h, achieving 95.95% ketone conversion with accompanying heavier alcohols in the absence
of an external hydrogen supply, demonstrating its potential as hydrogenation catalyst
Conservation Planning for Promoting Ecosystem Service Provisioning Outside Protected Area Networks
(British Ecological Society and John Wiley & Sons Ltd., 2025-11-17) Tarimo, Florence; Moyo, Francis; Kelly, Claire; Munishi, Linus
Among factors that contribute to global biodiversity loss, habitat loss through unsustainable land use and land cover changes
has gained prominence, with impacts being exacerbated by increasing human populations. Establishing protected area net-
works (PANs) is strongly advocated by national and international mechanisms, such as the Convention on Biological Diversity
(CBD), as a primary strategy to guide biodiversity conservation and management; however, this can undermine conservation
efforts outside protected areas. Understanding how people and biodiversity overlap and interact outside protected area networks
(OPAN areas) is essential for setting realistic, sustainable targets to guide biodiversity conservation and ecosystem service provi-
sion beyond PAN. However, how OPAN areas can sustain or enhance ecosystem services (ESs) through improved conservation
and management remains unassessed. We applied a novel ecosystem-based conservation (EBC) framework, using data from
Tanzania, to assess how biodiversity and land use/land cover (LULC) types shape the monetary value of selected ESs in OPAN
areas, and in future scenarios where restoration of priority wildlife corridors is implemented by 2030. Across the six ecosystems
and four LULC types assessed, waterbody delivered the highest ES value (US$12.8 billion) through water provision and flood
control. OPAN areas in miombo woodland also yielded high value (US$12.4 billion), with 46% from flood control and 54%
from water provision and carbon storage. ES values varied across OPANs, mainly driven by relative size and degradation level.
Restoring 197,497 ha of degraded land within 53 prioritised wildlife corridors in Tanzania could generate up to US$62.8 million
annually in ESs under full restoration, and US$31.4 million under partial restoration, with carbon storage contributing over 90%
of total value. Policy implications: The spatial heterogeneity and ES overlap observed highlight the need to integrate OPANs into
the EBC framework, linking local restoration gains with national policies and global biodiversity frameworks.
Evaluating the effectiveness of stochastic CTMC and deterministic models in correlating rabies persistence in human and dog populations
(Elsevier, 2025-10-24) Charles, Mfano; Mfinanga, Sayoki; Lyakurwa, G.; Torres, Delfim; Masanja, Verdiana G.
Rabies continues to pose a significant zoonotic threat, particularly in areas with high populations of domestic
dogs that serve as viral reservoirs. This study conducts a comparative analysis of Stochastic Continuous-Time
Markov Chain (CTMC) and deterministic models to gain insights into rabies persistence within human and
canine populations. By employing a multitype branching process, the stochastic threshold for rabies persistence
was determined, revealing important insights into how stochasticity influences extinction probabilities. The
stochastic model utilized 10,000 sample paths to estimate the probabilities of rabies outbreaks, offering
a rigorous assessment of the variability in disease occurrences. Additionally, the study introduces a novel
mathematical formulation of rabies transmission dynamics, which includes environmental reservoirs, free-
ranging dogs, and domestic dogs as essential transmission factors. The basic reproduction number (0) was
derived and analyzed within stochastic frameworks, effectively bridging the gap between these two modeling
approaches. Numerical simulations confirmed that the results from the stochastic model closely aligned with
those from the deterministic model, while also highlighting the importance of stochasticity in scenarios with
low infection rates. Ultimately, the study advocates for a comprehensive approach to rabies control that
integrates both the predictable trends identified through deterministic models and the impact of random events
emphasized by stochastic models.