| 1. |
- Cosme, Maximilien, et al.
(författare)
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Qualitative Modeling for Bridging Expert-Knowledge and Social-Ecological Dynamics of an East African Savanna
- 2022
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Ingår i: Land. - : MDPI AG. - 2073-445X. ; 11:1
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Tidskriftsartikel (refereegranskat)abstract
- Sub-Saharan social-ecological systems are undergoing changes in environmental conditions, including modifications in rainfall pattern and biodiversity loss. Consequences of such changes depend on complex causal chains which call for integrated management strategies whose efficiency could benefit from ecosystem dynamic modeling. However, ecosystem models often require lots of quantitative information for estimating parameters, which is often unavailable. Alternatively, qualitative modeling frameworks have proved useful for explaining ecosystem responses to perturbations, while only requiring qualitative information about social-ecological interactions and events and providing more general predictions due to their validity for wide ranges of parameter values. In this paper, we propose the Ecological Discrete-Event Network (EDEN), an innovative qualitative dynamic modeling framework based on if-then rules generating non-deterministic dynamics. Based on expert knowledge, observations, and literature, we use EDEN to assess the effect of permanent changes in surface water and herbivores diversity on vegetation and socio-economic transitions in an East African savanna. Results show that water availability drives changes in vegetation and socio-economic transitions, while herbivore functional groups have highly contrasted effects depending on the group. This first use of EDEN in a savanna context is promising for bridging expert knowledge and ecosystem modeling.
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| 2. |
- Felix, Nancy, et al.
(författare)
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Retaliatory killing negatively affects African lion (Panthera leo) male coalitions in the Tarangire-Manyara Ecosystem, Tanzania
- 2022
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 17:8
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Tidskriftsartikel (refereegranskat)abstract
- In landscapes where people and lions coexist, conflicts are common due to livestock predation and threats to human safety. Retaliatory lion killing by humans is often a consequence and is one of the leading causes of lion population declines across Africa. We assessed the effects of retaliatory lion killing on male lion coalitions in the Tarangire-Manyara Ecosystem (TME) using a long-term dataset of lion monitoring for ten lion prides, spanning over a fourteen year-period from 2004-2018. We also interviewed 214 respondents about their attitudes and awareness of the effects of retaliatory killing on lions. We found that male lion coalitions were larger and lasted for a longer tenure period in locations with low risk of retaliatory killing, as well as far away from active hunting blocks. Further, young people (18-35 years old) had a more positive attitude towards lion existence and conservation compared to older age classes. Surprisingly, people with primary or secondary level of education were more likely to having lions killed if they attack livestock compared to people with no formal education, although the former supported lion presence for tourism in protected areas. We conclude that retaliatory killing has a large effect on long-term lion coalition dynamics and, thus, survival. Community awareness on retaliation effect varies widely, and we recommend implementing better education and policy strategies at TME to protect the declining carnivore populations.
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| 3. |
- Levi, Matana, et al.
(författare)
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Forage selection by Masai giraffes (Giraffa camelopardalis tippelskirchi) at multiple spatial scales
- 2022
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Ingår i: Journal of Mammalogy. - : Oxford University Press (OUP). - 0022-2372 .- 1545-1542. ; 103:3, s. 737-744
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Tidskriftsartikel (refereegranskat)abstract
- Management of rangelands requires knowledge of forage species that are preferred or avoided by wildlife and livestock. A recent expansion of woody vegetation into previously open grasslands in African savanna ecosystems negatively impacts many mammalian grazers. Nevertheless, the ecological role of bush encroacher plant species as food may present a benefit for browsing species. We quantified diet selection by Masai giraffes (Giraffa camelopardalis tippelskirchi) through foraging observations and vegetation sampling in the Tarangire Ecosystem of Tanzania, which includes large areas of a native shrub that livestock managers have classified as an encroacher species (Dichrostachys cinerea). We compared woody plant species used by giraffes for foraging with availability at two different spatial scales during the wet and dry seasons. Giraffes selected some woody plants such as Vachellia species while significantly avoiding others, both at the local and landscape scales. Giraffes preferred foraging on D. cinerea at both spatial scales and in both the wet and dry seasons. Management that has focused on benefiting grazing livestock by removal of encroaching species (e.g., D. cinerea) may have unintended consequences for wildlife, especially for browsing species like giraffes that feed extensively on the expanding bush species.
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| 4. |
- Leweri, Cecilia M., et al.
(författare)
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Spatial and seasonal group size variation of wild mammalian herbivores in multiple use landscapes of the Ngorongoro Conservation Area, Tanzania
- 2022
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 17:4
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Tidskriftsartikel (refereegranskat)abstract
- Group sizes of wild herbivores can be indicators of ecosystem health and proxies for individual and population fitness, particularly in areas where human activities have become increasingly common. We recorded 176 single- and multi-species groups of wild herbivores in human-dominated landscapes of the Ngorongoro Conservation Area (NCA) during dry and wet seasons. We analyzed how wild herbivore group sizes were affected by: (1) season, (2) distance to fully protected area (NCA crater) and to streams, (3) distance to human settlements, and (4) numbers of livestock. Group sizes were generally larger during the wet season than during the dry season and varied seasonally with distance to NCA crater, streams, and human settlements. During the wet season, larger groups were observed further away from the NCA crater whereas the opposite pattern was apparent during the dry season. Average wild herbivore group sizes increased by about three-fold with increasing distance from the streams during the dry season but were invariant to streams during the wet season. Furthermore, during the dry season, group sizes were larger close to settlements but varied little with distance to settlements during the wet season. While livestock presence did not directly affect wild herbivore group size, distance to settlements, streams and distance to the Ngorongoro crater in interaction with rainfall seasonality did. We conclude that the NCA crater functions as a key resource area for wild herbivores such as wildebeest (Connochaetes taurinus) and zebra (Equus quagga burchelli) during the dry season, highlighting the need for its full protection status in this Man and Biosphere reserve.
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| 5. |
- Michler, Lena M., et al.
(författare)
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Moving Toward the Greener Side : Environmental Aspects Guiding Pastoral Mobility and Impacting Vegetation in the Dzungarian Gobi, Mongolia
- 2022
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Ingår i: Rangeland Ecology & Management. - : Elsevier BV. - 1550-7424 .- 1551-5028. ; 83, s. 149-160
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Tidskriftsartikel (refereegranskat)abstract
- Livestock grazing often intensifies around herder camps, which can lead to degradation, particularly in arid areas, where vegetation is scarce. In Mongolia, nomadic herders have covered long distances between camps and changed camps regularly for centuries. However, changing socioeconomics, rising livestock numbers, and climatic change have led to growing concerns over rangeland health. To understand travel mobility and livestock grazing patterns, we combined Global Positioning System tracking data of goats, remotely sensing pasture productivity, and ground-based vegetation characteristics in the Great Gobi B Strictly Protected Area, Mongolia. We assessed herder preferences for camp selection, followed 19 livestock herds over 20 months, determined use and nutrient contents of the most dominant plant communities, and estimated plant species richness, vegetation cover, and biomass within different grazing radii around camps. Biomass availability was key for herder decisions to move camps, but in winter, other factors like shelter from wind were more important. Camps were mainly located in Stipa spp. communities, agreeing with herder preferences for this highly nutritious species, and its dominance around camps. Herders changed their camp locations on average 9 times yearly, with a maximum distance of 70–123 km between summer and winter camps, and an average visitation period of 25–49 d per camp, depending on season. Small livestock spent > 13−17 h daily within a radius of 100 m from camp, and livestock use intensity decreased steeply with distance from camp but was remarkably similar around spring, autumn, and winter camps on the Gobi plains. However, we found little evidence for a corresponding gradient in plant species richness, biomass, and cover on the Gobi plains. The high mobility of local herders and the overriding impact of precipitation on pasture dynamics contribute to a sustainable vegetation offtake by livestock in the nonequilibrium rangelands of the Dzungarian Gobi.
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| 6. |
- Mohammed, Elmugheira M. I., et al.
(författare)
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Livestock Browsing Threatens the Survival of Balanites aegyptiaca Seedlings and Saplings in Dinder Biosphere Reserve, Sudan
- 2022
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Ingår i: Journal of Sustainable Forestry. - : Informa UK Limited. - 1054-9811 .- 1540-756X. ; 41:10, s. 1046-1063
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Tidskriftsartikel (refereegranskat)abstract
- While the impact of livestock grazing has been frequently assessed for grasses, little is known about how livestock affects tree seedlings and saplings. We explored the effects of goat, cattle and camel browsing on the survival of Balanites aegyptiaca seedlings and saplings, a broadleaved evergreen tree species indigenous to Sudan, in Dinder Biosphere Reserve-Sudan (DBR). We used a stratified sampling design with four sites: GOA (mainly browsed by goats), CAT and CAM being mainly browsed by cattle and camels, respectively, while CON was a control area without any livestock browsing. We tested the survival, mortality and recovery of seedlings and saplings across different sites. Our results revealed that mortalities of seedlings in GOA were almost four times higher than that of CAM and CON and twice that of CAT (F3,196 = 100.39, P < .001). Further, sapling mortality was three times higher in GOA than that observed in CAT and CON (F3,196 = 73.4, P < .001). We found that seedlings recover better than saplings, and, unexpectedly, goat browsing severely affected the natural regeneration of B. aegyptiaca in DBR compared to other livestock species. Our study findings contribute to sustainable forest management and show that particularly goat browsing needs to be suppressed for conservation of vulnerable tree species.
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| 7. |
- Mohammed, Elmugheira M. I., et al.
(författare)
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The stocking density and regeneration status of Balanites aegyptiaca in Dinder Biosphere Reserve, Sudan
- 2022
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Ingår i: Trees, Forests and People. - : Elsevier BV. - 2666-7193. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- Balanites aegyptiaca as food, feed, and medicinal tree species, contributes significantly to the livelihoods and food security of forest-based communities, particularly in the Sahel. However, up-to-date information on the stocking density and regeneration status of the species is lacking. The current study bridged this gap and explored the species status in Dinder Biosphere Reserve, Sudan, across 150 sample plots of 40×25 m2 randomly distributed in the stratified sites of the reserve. After checking for normality using Shapiro Wilk test, a two-way ANOVA with Tukey's post hoc test (α = 0.05) in JAMOVI (Version 1.1.7) has been used to compare the tree density, basal area, and volume between the assessed sites and within the sites. The study found that the stocking density of B. aegyptiaca seedlings, saplings, and adult trees in the non-disturbed sites were double and three times equal to that of the highly disturbed sites and significantly differed between sites (F2,147 = 122.4 and P < 0.001; F2,147 = 148.3 and P = 0.001; F2,147 = 131.2 and P = 0.021, respectively). Moreover, the smallest tree crown diameter, basal area, and volume were observed in the highly disturbed sites. The study concluded that unbalanced utilization of B. aegyptiaca in the biosphere severely reduced the species population and disturbed their dynamics, which might also affect the food security in the area. Therefore, an introduction of monitoring and awareness-raising programs is urgently needed to maintain this valuable tree species and manage it sustainably.
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| 8. |
- Msaki, Gerubin Liberath, et al.
(författare)
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Social knowledge, attitudes, and perceptions on wastewater treatment, technologies, and reuse in Tanzania
- 2022
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Ingår i: Water Reuse. - : IWA Publishing. - 2709-6092 .- 2709-6106. ; 12:2, s. 223-241
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Tidskriftsartikel (refereegranskat)abstract
- This study assessed the social knowledge, attitude, and perceptions (KAPs) on wastewater treatment, the technologies involved, and its reuse across different wastewater treatment areas in four regions of Tanzania. We used both quantitative and qualitative data collection methods in a household-level questionnaire (n=327) with structured and semi-structured questions, which involved face-to-face interviews and observation. Our results show that social KAPs surrounding wastewater treatment and reuse were sufficient based on KAP scores achieved from asked questions. However, the general knowledge on treatment technologies, processes, and reuse risks was still low. Of the respondents, over 50% approved using treated wastewater in various applications, while the majority (93%) were reluctant if the application involved direct contact with the water. Furthermore, over 90% of interviewees did not know the technologies used to treat wastewater and the potential health risks associated with its use (59%). Multivariate analysis of variance revealed significant differences (P<0.05) in the KAPs on treated wastewater across different studied demographic variables, i.e., age, sex, and education level. Therefore, we recommend that more effort be spent on providing public education about the potential of wastewater treatment and existing technologies in order to facilitate their adoption for the community's and environment's benefit.
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| 9. |
- Musika, Nyangabo V., et al.
(författare)
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Using Trophy Hunting to Save Wildlife Foraging Resources : A Case Study from Moyowosi-Kigosi Game Reserves, Tanzania
- 2022
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Ingår i: Sustainability. - : MDPI AG. - 2071-1050. ; 14:3
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Tidskriftsartikel (refereegranskat)abstract
- Globally, the role of trophy hunting in wildlife conservation has been a topic of much debate. While various studies have focused on the financial contribution of trophy hunting towards wildlife conservation, little is known about whether hunting activities can protect wildlife forage resources. We examined the effect of illegal livestock grazing on wildlife habitat in operational and non-operational wildlife hunting blocks in Moyowosi-Kigosi Game Reserves (MKGR), Tanzania. We assessed whether the physical presence of hunting activities lowered illegal grazing and, thus, led to higher vegetation quality. We compared 324 samples of above-ground biomass (AGB) and grass cover between control (0.0007 cattle ha−1), moderately (0.02 cattle ha−1), and intensively (0.05 to 0.1 cattle ha−1) grazed hunting blocks. Likewise, we assessed soil infiltration, soil penetration, soil organic carbon (SOC), and soil Nitrogen, Phosphorus, and Potassium (N-P-K) across grazing intensity. Illegal grazing decreased AGB by 55%, grass cover by 36%, soil penetration by 46%, and infiltration rate by 63% compared to the control blocks. Illegal grazing further lowered SOC by 28% (F2,33 = 8, p < 0.002) but increased soil N by 50% (F2,33 = 32.2, p < 0.001) and soil K by 56% (H (2) = 23.9, p < 0.001), while soil P remained stable. We further examined if Hunting Company (HC) complements anti-poaching efforts in the Game Reserves (GR). We found that HC contributes an average of 347 worker-days−1 for patrol efforts, which is 49% more than the patrol efforts conducted by the GR. However, patrol success is higher for GR than HC (F1,21 = 116, p < 0.001), due to constant surveillance by HC, illegal herders avoided invading their hunting blocks. We conclude that illegal grazing severely reduced vegetation and soil quality in MKGR. We further claim that trophy hunting contributes directly to wildlife habitat preservation by deploying constant surveillance and preventing illegal grazing. We propose maintaining trophy hunting as an essential ecological tool in wildlife conservation.
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| 10. |
- Shayo, Philipina F., et al.
(författare)
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Growth performance of the neglected crop Telfairia pedata across elevation and climate gradients in Northern Tanzania
- 2022
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Ingår i: Trees, Forests and People. - : Elsevier BV. - 2666-7193. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- Herbaceous vines, including the neglected crop Telfairia pedata, play a key role in small-holder livelihoods of Eastern Africa. Despite this species’ importance in enhancing agro-biodiversity, little is known about its distribution and growth performance in relation to environmental variables. We collected biophysical and environmental data, i.e., on climate and elevation, for 346 T. pedata vines across four districts of Northern Tanzania from September, 2019, to February, 2020. The four sites included Same, Lushoto, Muheza and Arumeru districts. We found that plants of T. pedata were mainly grown in elevations ranging between 900 to 1800 m above sea level with annual rainfall regimes of 1000 to 1400 mm. We recorded large abundance of T. pedata in Lushoto (46%) and Arumeru (28%) and observed that the number of fruits and fruit diameter were both positively correlated with elevation across the study districts. There was a significant effect of elevation on number of seeds, with Same district having more seeds across the studied districts. Rainfall had a significant effect on fruit diameter and number of seeds in the study districts. Furthermore, the tree species Albizia schimperiana was most commonly (in 40% of the cases) associated with T. pedata, followed by Persea americana (14%), and Croton macrostachyus (9%). We highlight that mountainous regions are ideal for this highly nutritious crop, and that native trees are of high importance for enriching this vine to current agro-ecosystems. Our findings will increase awareness on the importance of raising T. pedata crop, livelihood diversification, and increasing biodiversity through production of this orphan crop in small-holder farms.
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