Predicting range shifts of African apes under global change scenarios

ABSTRACTAimModelling African great ape distribution has until now focused on current or past conditions, whilst future scenarios remain scarcely explored. Using an ensemble forecasting approach, we predicted changes in taxon-specific distribution under future scenarios of climate, land-use and human population changes.LocationSub-Saharan AfricaMethodsWe compiled occurrence data on African ape populations from the IUCN A.P.E.S. database and extracted relevant human-, climate- and habitat-related predictors representing current and future (2050) conditions to predict taxon-specific distribution under a best- and a worst-case scenario, using ensemble forecasting. Given the large effect on model predictions, we further tested algorithm sensitivity by considering default and non-default modelling options. The latter included interactions between predictors and polynomial terms in correlative algorithms.ResultsThe future distributions of gorilla and bonobo populations are likely to be directly determined by climate-related variables. In contrast, future chimpanzee distribution is influenced mostly by anthropogenic variables. Both our modelling approaches produced similar model accuracy, although a slight difference in the magnitude of range change was found for Gorilla beringei beringei, G. gorilla diehli, and Pan troglodytes schweinfurthii. On average, a decline of 50% of the geographic range (non-default; or 55% default) is expected under the best scenario if no dispersal occurs (57% non-default or 58% default in worst scenario). However, new areas of suitable habitat are predicted to become available for most taxa if dispersal occurs (81% or 103% best, 93% or 91% worst, non-default and default, respectively), except for G. b. beringei.Main ConclusionsDespite the uncertainty in predicting the precise proportion of suitable habitat by 2050, both modelling approaches predict large range losses for all African apes. Thus, conservation planners urgently need to integrate land-use planning and simultaneously support conservation and climate change mitigation measures at all decision-making levels both in range countries and abroad.

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Climate change favours connectivity between virus-bearing pest and rice cultivations in sub-Saharan Africa, depressing local economies

PeerJ ◽

10.7717/peerj.12387 ◽

2021 ◽

Vol 9 ◽

pp. e12387

Author(s):

Mattia Iannella ◽

Walter De Simone ◽

Paola D’Alessandro ◽

Maurizio Biondi

Keyword(s):

Land Use ◽

Ecological Niche ◽

Ecological Niche Modelling ◽

Rice Production ◽

Sub Saharan Africa ◽

Rice Yellow Mottle Virus ◽

Future Scenarios ◽

Niche Modelling ◽

The Future ◽

Sub Saharan

Aims Rice is a staple food for many countries, being fundamental for a large part of the worlds’ population. In sub-Saharan Africa, its importance is currently high and is likely to become even more relevant, considering that the number of people and the per-capita consumption are both predicted to increase. The flea beetles belonging to the Chaetocnema pulla species group (pulla group), a harmful rice pest, are an important vector of the Rice Yellow Mottle Virus, a disease which leads even to 80–100% yield losses in rice production. We present a continental-scale study aiming at: (1) locating current and future suitable territories for both pulla group and rice; (2) identifying areas where rice cultivations may occur without suffering the presence of pulla group using an Ecological Niche Modelling (ENM) approach; (3) estimating current and future connectivity among pulla group populations and areas predicted to host rice cultivations, based on the most recent land-use estimates for future agricultural trends; (4) proposing a new connectivity index called “Pest Aggression Index” (PAI) to measure the agricultural susceptibility to the potential future invasions of pests and disease; (5) quantifying losses in terms of production when rice cultivations co‐occur with the pulla group and identifying the SSA countries which, in the future inferred scenarios, will potentially suffer the greatest losses. Location Sub-Saharan Africa. Methods Since the ongoing climate and land-use changes affect species’ distributions, we first assess the impact of these changes through a spatially-jackknifed Maxent-based Ecological Niche Modelling in GIS environment, for both the pulla group and rice, in two climatic/socioeconomic future scenarios (SSP_2.45 and 3.70). We then assess the connectivity potential of the pulla group populations towards rice cultivations, for both current and future predictions, through a circuit theory-based approach (Circuitscape implemented in Julia language). We finally measure the rice production and GPD loss per country through the spatial index named “Pest Aggression Index”, based on the inferred connectivity magnitude. Results The most considerable losses in rice production are observed for Liberia, Sierra Leone and Madagascar in all future scenarios (2030, 2050, 2070). The future economic cost, calculated as USD lost from rice losses/country’s GDP results are high for Central African Republic (−0.6% in SSP_2.45 and −3.0% in SSP_3.70) and Guinea–Bissau (−0.4% in SSP_2.45 and −0.68% in SSP_3.70), with relevant losses also obtained for other countries. Main conclusions Since our results are spatially explicit and focused on each country, we encourage careful land-use planning. Our findings could support best practices to avoid the future settlement of new cultivations in territories where rice would be attacked by pulla group and the virus, bringing economic and biodiversity losses.

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Faculty Opinions recommendation of Land-use change outweighs projected effects of changing rainfall on tree cover in sub-Saharan Africa.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.726299825.793533303 ◽

2017 ◽

Author(s):

George Malanson

Keyword(s):

Land Use ◽

Land Use Change ◽

Sub Saharan Africa ◽

Tree Cover ◽

Sub Saharan

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Land-Use Management and Carbon Sequestering in Sub-Saharan Africa

Journal of Environmental Systems ◽

10.2190/552y-ad1t-nmxq-n536 ◽

1992 ◽

Vol 22 (3) ◽

pp. 199-210 ◽

Cited By ~ 2

Author(s):

R. D. Perlack ◽

R. L. Graham ◽

A. M. G. Prasad

Keyword(s):

Land Use ◽

Sub Saharan Africa ◽

Land Use Management ◽

Carbon Sequestering ◽

Sub Saharan

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Ecological and Environmental Effects of Estuarine Wetland Loss Using Keyhole and Landsat Data in Liao River Delta, China

Remote Sensing ◽

10.3390/rs13020311 ◽

2021 ◽

Vol 13 (2) ◽

pp. 311

Author(s):

Hongyan Yin ◽

Yuanman Hu ◽

Miao Liu ◽

Chunlin Li ◽

Jiujun Lv

Keyword(s):

Heavy Metal ◽

Land Use ◽

Land Use Change ◽

Ecological Risk ◽

Potential Ecological Risk ◽

Wetland Loss ◽

Ecological Effects ◽

Paddy Fields ◽

Suitable Habitat ◽

Estuarine Wetland

An estuarine wetland is an area of high ecological productivity and biodiversity, and it is also an anthropic activity hotspot area, which is of concern. The wetlands in estuarine areas have suffered declines, which have had remarkable ecological impacts. The land use changes, especially wetland loss, were studied based on Keyhole and Landsat images in the Liao River delta from 1962 to 2016. The dynamics of the ecosystem service values (ESVs), suitable habitat for birds, and soil heavy metal potential ecological risk were chosen to estimate the ecological effects with the benefit transfer method, synthetic overlaying method, and potential ecological risk index (RI) method, respectively. The driving factors of land use change and ecological effects were analyzed with redundancy analysis (RDA). The results showed that the built-up area increased from 95.98 km2 in 1962 to 591.49 km2 in 2016, and this large change was followed by changes in paddy fields (1351.30 to 1522.39 km2) and dry farmland (189.5 to 294.14 km2). The area of wetlands declined from 1823.16 km2 in 1962 to 1153.52 km2 in 2016, and this change was followed by a decrease in the water area (546.2 to 428.96 km2). The land use change was characterized by increasing built-up (516.25%), paddy fields (12.66%) and dry farmland (55.22%) areas and a decline in the wetland (36.73%) and water areas (21.47%) from 1962–2016. Wetlands decreased by 669.64 km2. The ESV values declined from 6.24 billion US$ to 4.46 billion US$ from 1962 to 2016, which means the ESVs were reduced by 19.26% due to wetlands being cultivated and the urbanization process. The area of suitable habitat for birds decreased by 1449.49 km2, or 61.42% of the total area available in 1962. Cd was the primary soil heavy metal pollutant based on its concentration, accumulation, and potential ecological risk contribution. The RDA showed that the driving factors of comprehensive ecological effects include wetland area, Cd and Cr concentration, river and oil well distributions. This study provides a comprehensive approach for estuarine wetland cultivation and scientific support for wetland conservation.

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Future scenarios impact on land use change and habitat quality in Lithuania

Environmental Research ◽

10.1016/j.envres.2021.111101 ◽

2021 ◽

pp. 111101

Author(s):

Eduardo Gomes ◽

Miguel Inácio ◽

Katažyna Bogdzevič ◽

Marius Kalinauskas ◽

Donalda Karnauskaitė ◽

...

Keyword(s):

Land Use ◽

Land Use Change ◽

Habitat Quality ◽

Future Scenarios

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Key Challenges for Land Use Planning and Its Environmental Assessments in the Abuja City-Region, Nigeria

Land ◽

10.3390/land10050443 ◽

2021 ◽

Vol 10 (5) ◽

pp. 443

Author(s):

Evidence Chinedu Enoguanbhor ◽

Florian Gollnow ◽

Blake Byron Walker ◽

Jonas Ostergaard Nielsen ◽

Tobia Lakes

Keyword(s):

Land Use ◽

Land Cover ◽

Environmental Assessment ◽

Land Use Planning ◽

Environmental Sustainability ◽

Sub Saharan Africa ◽

Environmental Assessments ◽

City Regions ◽

Sub Saharan ◽

Land Cover Maps

Land use planning as strategic instruments to guide urban dynamics faces particular challenges in the Global South, including Sub-Saharan Africa, where urgent interventions are required to improve urban and environmental sustainability. This study investigated and identified key challenges of land use planning and its environmental assessments to improve the urban and environmental sustainability of city-regions. In doing so, we combined expert interviews and questionnaires with spatial analyses of urban and regional land use plans, as well as current and future urban land cover maps derived from Geographic Information Systems and remote sensing. By overlaying and contrasting land use plans and land cover maps, we investigated spatial inconsistencies between urban and regional plans and the associated urban land dynamics and used expert surveys to identify the causes of such inconsistencies. We furthermore identified and interrogated key challenges facing land use planning, including its environmental assessment procedures, and explored means for overcoming these barriers to rapid, yet environmentally sound urban growth. The results illuminated multiple inconsistencies (e.g., spatial conflicts) between urban and regional plans, most prominently stemming from conflicts in administrative boundaries and a lack of interdepartmental coordination. Key findings identified a lack of Strategic Environmental Assessment and inadequate implementation of land use plans caused by e.g., insufficient funding, lack of political will, political interference, corruption as challenges facing land use planning strategies for urban and environmental sustainability. The baseline information provided in this study is crucial to improve strategic planning and urban/environmental sustainability of city-regions in Sub-Saharan Africa and across the Global South, where land use planning faces similar challenges to address haphazard urban expansion patterns.

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Using Participatory Spatial Tools to Unravel Community Perceptions of Land-Use Dynamics in a Mine-Expanding Landscape in Ghana

Environmental Management ◽

10.1007/s00267-021-01494-7 ◽

2021 ◽

Author(s):

Jane J. Aggrey ◽

Mirjam A. F. Ros-Tonen ◽

Kwabena O. Asubonteng

Keyword(s):

Land Use ◽

Adverse Effects ◽

Large Scale ◽

Sub Saharan Africa ◽

Small Scale ◽

Eastern Region ◽

Food Crop ◽

Mosaic Landscape ◽

Rural Landscapes ◽

The Future

AbstractArtisanal and small-scale mining (ASM) in sub-Saharan Africa creates considerable dynamics in rural landscapes. Many studies addressed the adverse effects of mining, but few studies use participatory spatial tools to assess the effects on land use. Hence, this paper takes an actor perspective to analyze how communities in a mixed farming-mining area in Ghana’s Eastern Region perceive the spatial dynamics of ASM and its effects on land for farming and food production from past (1986) to present (2018) and toward the future (2035). Participatory maps show how participants visualize the transformation of food-crop areas into small- and large-scale mining, tree crops, and settlement in all the communities between 1986 and 2018 and foresee these trends to continue in the future (2035). Participants also observe how a mosaic landscape shifts toward a segregated landscape, with simultaneous fragmentation of their farming land due to ASM. Further segregation is expected in the future, with attribution to the expansion of settlements being an unexpected outcome. Although participants expect adverse effects on the future availability of food-crop land, no firm conclusions can be drawn about the anticipated effect on food availability. The paper argues that, if responsibly applied and used to reveal community perspectives and concerns about landscape dynamics, participatory mapping can help raise awareness of the need for collective action and contribute to more inclusive landscape governance. These findings contribute to debates on the operationalization of integrated and inclusive landscape approaches and governance, particularly in areas with pervasive impacts of ASM.

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An Approach to Complement Model-Based Vehicle Development by Implementing Future Scenarios

World Electric Vehicle Journal ◽

10.3390/wevj12030097 ◽

2021 ◽

Vol 12 (3) ◽

pp. 97

Author(s):

Christian Raulf ◽

Moritz Proff ◽

Tobias Huth ◽

Thomas Vietor

Keyword(s):

Systems Engineering ◽

Holistic Approach ◽

Future Scenarios ◽

Worst Case ◽

System Architectures ◽

Vehicle Development ◽

Model Based ◽

Scenario Technique ◽

Stakeholder Needs ◽

Model Based Systems Engineering

Today, vehicle development is already in a process of substantial transformation. Mobility trends can be derived from global megatrends and have a significant influence on the requirements of the developed vehicles. The sociological, technological, economic, ecological, and political developments can be determined by using the scenario technique. The results are recorded in the form of differently shaped scenarios; however, they are mainly document-based. In order to ensure a holistic approach in the sense of model-based systems engineering and to be able to trace the interrelationships of the fast-changing trends and requirements, it is necessary to implement future scenarios in the system model. For this purpose, a method is proposed that enables the consideration of future scenarios in model-based vehicle development. The procedure of the method is presented, and the location of the future scenarios within the system architectures is named. The method is applied and the resulting system views are derived based on the application example of an autonomous people mover. With the help of the described method, it is possible to show the effects of a change of scenario (e.g., best-case and worst-case) and the connections with the highest level of requirements: stakeholder needs.

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Within-Season Changes in Land-Use Impact Pest Abundance in Smallholder African Cassava Production Systems

Insects ◽

10.3390/insects12030269 ◽

2021 ◽

Vol 12 (3) ◽

pp. 269 ◽

Cited By ~ 1

Author(s):

Andrew Kalyebi ◽

Sarina Macfadyen ◽

Andrew Hulthen ◽

Patrick Ocitti ◽

Frances Jacomb ◽

...

Keyword(s):

Land Use ◽

Bemisia Tabaci ◽

Large Scale ◽

Production Systems ◽

Smallholder Farmers ◽

Negative Relationship ◽

Central Africa ◽

Sub Saharan Africa ◽

Smallholder Farming ◽

Manihot Esculenta Crantz

Cassava (Manihot esculenta Crantz), an important commercial and food security crop in East and Central Africa, continues to be adversely affected by the whitefly Bemisia tabaci. In Uganda, changes in smallholder farming landscapes due to crop rotations can impact pest populations but how these changes affect pest outbreak risk is unknown. We investigated how seasonal changes in land-use have affected B. tabaci population dynamics and its parasitoids. We used a large-scale field experiment to standardize the focal field in terms of cassava age and cultivar, then measured how Bemisia populations responded to surrounding land-use change. Bemisia tabaci Sub-Saharan Africa 1 (SSA1) was identified using molecular diagnostics as the most prevalent species and the same species was also found on surrounding soybean, groundnut, and sesame crops. We found that an increase in the area of cassava in the 3–7-month age range in the landscape resulted in an increase in the abundance of the B. tabaci SSA1 on cassava. There was a negative relationship between the extent of non-crop vegetation in the landscape and parasitism of nymphs suggesting that these parasitoids do not rely on resources in the non-crop patches. The highest abundance of B. tabaci SSA1 nymphs in cassava fields occurred at times when landscapes had large areas of weeds, low to moderate areas of maize, and low areas of banana. Our results can guide the development of land-use strategies that smallholder farmers can employ to manage these pests.

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Prospective cohort study of Kaposi sarcoma treated under real-world conditions in Malawi.

Journal of Clinical Oncology ◽

10.1200/jco.2021.39.15_suppl.11569 ◽

2021 ◽

Vol 39 (15_suppl) ◽

pp. 11569-11569

Author(s):

Edwards Kasonkanji ◽

Yolanda Gondwe ◽

Morgan Dewey ◽

Joe Gumulira ◽

Matthew Painschab ◽

...

Keyword(s):

Cohort Study ◽

Kaposi Sarcoma ◽

Median Number ◽

Sub Saharan Africa ◽

Worst Case ◽

Loss To Follow Up ◽

Presenting Symptoms ◽

Grade 3 ◽

Lost To Follow Up

11569 Background: Kaposi sarcoma (KS) is the leading cancer in Malawi (34% of cancers). Outside of clinical trials, prospective KS studies from sub-Saharan Africa (SSA) are few and limited by loss to follow up. We conducted a prospective KS cohort study of standard of care bleomycin/vincristine (BV) at Lighthouse HIV clinic, in Lilongwe, Malawi. Methods: We enrolled pathologically confirmed, newly diagnosed, HIV+ KS patients from Feb 2017 to Jun 2019. We collected clinical and treatment characteristics, toxicity, and outcomes of KS with follow-up censored Jun 2020. Patients were treated with bleomycin (25 mg/m2) and vincristine (0.4 mg/m2) every 14 days for a planned maximum of 16 cycles. STATA v13.0 was used to calculate descriptive statistics and Kaplan Meier survival analysis. Toxicity was graded using NCI CTCAE v5.0. Results: We enrolled 138 participants, median age 36 (IQR 32-44) and 110 (80%) male. By ACTG staging, 107 (78%) were T1 (tumour severity), 46 (33%) were S1 (illness severity) and 46 (33%) had Karnofsky performance status ≤70. Presenting symptoms included edema in 69 (53%), visceral disease in 9 (7%), and oral involvement in 43 (33%). Prior to KS diagnosis, 70 (51%) participants were aware of being HIV+ for median 17 months (IQR 6-60) and had been on ART for median 16 months (IQR 6-60). Median CD4 count was 197 (IQR 99-339), median HIV-viral load was 2.6 log copies/mL (IQR 1.6 – 4.8) and 57% were HIV-suppressed ( < 1000 HIV copies/ml). The median number of cycles was 16 (IQR 7-16). 62 (45%) participants missed at least one dose due to stock out. Amongst patients with missed doses, the median number was 3 (IQR 2-4) for bleomycin and 2 (IQR 1-3) for vincristine. 14 (10%) participants experienced at least one reduced dose due to toxicity. 5 (4%) participants suffered grade ≥3 anaemia, 13 (9%) grade ≥3 neutropenia, and one participant had grade 4 bleomycin-induced dermatitis. There was no reported grade ≥3 bleomycin lung toxicity or vincristine-induced neuropathy. Of 115 evaluable participants, responses at the end of therapy were: complete response in 52 (45%), partial response in 27 (23%) stable disease in 5 (4%), and progressive disease in 31 (28%). Median duration of follow-up was 20 months. At censoring, 69 (50%) were alive, 36 (26%) dead, and 33 (24%) lost to follow-up. Overall survival is shown Table as crude and worst-case scenario; worst-case assumes all participants lost to follow up died. Conclusions: Here, we present one of the most complete characterizations of KS presentation and treatment from SSA. As in other studies from the region, the majority of patients presented with advanced disease, chemotherapy stock-outs and loss to follow up were common, and mortality was high. Studies are planned to understand the virologic characteristics, improve therapies, and better implement existing therapies.[Table: see text]

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