scholarly journals Long-Term Vegetation Change in Central Africa: The Need for an Integrated Management Framework for Forests and Savannas

2020 ◽  
pp. 281-315
Author(s):  
Julie C. Aleman ◽  
Adeline Fayolle
Keyword(s):  
Vegetation Change ◽  
Integrated Management ◽  
Central Africa ◽  
Management Framework

scholarly journals A conceptual framework for integrated management of Post-Natural Disasters Recovery (PNDR) projects

2021 ◽  
Author(s):  
Homa Bahmani ◽  
Wei Zhang
Keyword(s):  
Life Cycle ◽  
Natural Disasters ◽  
Natural Disaster ◽  
Construction Projects ◽  
Integrated Management ◽  
Significant Degree ◽  
Simultaneous Application ◽  
Management Framework

Abstract Following the increasing rate of natural disasters, more attention is being paid to post-natural disaster reconstruction projects. However, from the perspective of project management, these projects show a significant degree of differences from the regular construction projects. Although some progress has been made on this topic, further research is needed to smooth pathways for the management of Post-Natural Disaster Recovery (PNDR) projects. This paper provides a management framework for PNDR projects throughout the qualitative analysis of the research's selected resources. The resources identified by applying inclusion and exclusion criteria in academic online platforms have been coded by NVivo 2020, and corresponding groups have been made for PNDR life-cycle and project stages. An integrated management framework has been put forward throughout the simultaneous application of the research's suggested life-cycle and project stages for PNDR projects. The most significant observation of this study is the necessity of applying a continuous life-cycle to address projects' long-term goals and provide an experience-based database for the management of next natural disasters. The significant role of planning in the entire life-cycle of PNDR projects, recognition of the tasks that need to be handled continuously during entire PNDR projects, the necessity of simultaneous consideration of tangible and intangible recovery outcomes are the other findings of this study. Recognition of reconstruction as part of the bigger system, named recovery, also stressed the necessity of considering the recovery project as a whole.

scholarly journals Domain Adaptation for Semantic Segmentation of Historical Panchromatic Orthomosaics in Central Africa

2021 ◽  
Vol 10 (8) ◽  
pp. 523
Author(s):  
Nicholus Mboga ◽  
Stefano D’Aronco ◽  
Tais Grippa ◽  
Charlotte Pelletier ◽  
Stefanos Georganos ◽  
...  
Keyword(s):  
Land Cover ◽  
Domain Adaptation ◽  
Central Africa ◽  
Semantic Segmentation ◽  
Target Domain ◽  
Convolutional Networks ◽  
Fully Convolutional Networks ◽  
The Cost ◽  
Performance Gains

Multitemporal environmental and urban studies are essential to guide policy making to ultimately improve human wellbeing in the Global South. Land-cover products derived from historical aerial orthomosaics acquired decades ago can provide important evidence to inform long-term studies. To reduce the manual labelling effort by human experts and to scale to large, meaningful regions, we investigate in this study how domain adaptation techniques and deep learning can help to efficiently map land cover in Central Africa. We propose and evaluate a methodology that is based on unsupervised adaptation to reduce the cost of generating reference data for several cities and across different dates. We present the first application of domain adaptation based on fully convolutional networks for semantic segmentation of a dataset of historical panchromatic orthomosaics for land-cover generation for two focus cities Goma-Gisenyi and Bukavu. Our experimental evaluation shows that the domain adaptation methods can reach an overall accuracy between 60% and 70% for different regions. If we add a small amount of labelled data from the target domain, too, further performance gains can be achieved.

Herbivory, hunting, and long-term vegetation change in degraded savanna

2008 ◽  
Vol 141 (9) ◽  
pp. 2174-2183 ◽  
Author(s):  
A.S. MacDougall
Keyword(s):  
Vegetation Change

Can an integrated management approach provide a basis for long-term prevention of weed dominance in Australian pasture systems?

Weed Research ◽  
2005 ◽  
Vol 45 (3) ◽  
pp. 175-192 ◽  
Author(s):  
R K HUWER ◽  
D T BRIESE ◽  
P M DOWLING ◽  
D R KEMP ◽  
W M LONSDALE ◽  
...  
Keyword(s):  
Integrated Management ◽  
Management Approach

A quantitative synthesis of Holocene vegetation change in Nigeria (Western Africa)

The Holocene ◽  
2021 ◽  
pp. 095968362110331
Author(s):  
Matthew Adesanya Adeleye ◽  
Simon Edward Connor ◽  
Simon Graeme Haberle
Keyword(s):  
Vegetation Change ◽  
Climatic Changes ◽  
The Holocene ◽  
Continental Scale ◽  
Western Africa ◽  
Chord Distance ◽  
Quantitative Synthesis ◽  
Climatic Regime ◽  
Pollen Records

Understanding long-term (centennial–millennial scale) ecosystem stability and dynamics are key to sustainable management and conservation of ecosystem processes under the currently changing climate. Fossil pollen records offer the possibility to investigate long-term changes in vegetation composition and diversity on regional and continental scales. Such studies have been conducted in temperate systems, but are underrepresented in the tropics, especially in Africa. This study attempts to synthesize pollen records from Nigeria (tropical western Africa) and nearby regions to quantitatively assess Holocene regional vegetation changes (turnover) and stability under different climatic regimes for the first time. We use the squared chord distance metric (SCD) to assess centennial-scale vegetation turnover in pollen records. Results suggest vegetation in most parts of Nigeria experienced low turnover under a wetter climatic regime (African Humid Period), especially between ~8000 and 5000 cal year BP. In contrast, vegetation turnover increased significantly under the drier climatic regime of the late-Holocene (between ~5000 cal year BP and present), reflecting the imp role of moisture changes in tropical west African vegetation dynamics during the Holocene. Our results are consistent with records of vegetation and climatic changes in other parts of Africa, suggesting the Holocene pattern of vegetation change in Nigeria is a reflection of continental-scale climatic changes.

Rising ecosystem water demand exacerbates the lengthening of tropical dry seasons

2021 ◽  
Author(s):  
Hao Xu ◽  
Xu Lian ◽  
Ingrid Slette ◽  
Hui Yang ◽  
Yuan Zhang ◽  
...  
Keyword(s):  
Water Demand ◽  
Potential Evapotranspiration ◽  
Central Africa ◽  
Dry Season ◽  
Land Area ◽  
Key Factor ◽  
Dry Seasons ◽  
The Tropics ◽  
Factor Governing

Abstract The timing and length of the dry season is a key factor governing ecosystem productivity and the carbon cycle of the tropics. Mounting evidence has suggested a lengthening of the dry season with ongoing climate change. However, this conclusion is largely based on changes in precipitation (P) compared to its long-term average (P ̅) and lacks consideration of the simultaneous changes in ecosystem water demand (measured by potential evapotranspiration, Ep, or actual evapotranspiration, E). Using several long-term (1979-2018) observational datasets, we compared changes in tropical dry season length (DSL) and timing (dry season arrival, DSA, and dry season end, DSE) among three common metrics used to define the dry season: P < P ̅, P < Ep, and P < E. We found that all three definitions show that dry seasons have lengthened in much of the tropics since 1979. Among the three definitions, P < E estimates the largest fraction (49.0%) of tropical land area likely experiencing longer dry seasons, followed by P < Ep (41.4%) and P < P ̅ (34.4%). The largest differences in multi-year mean DSL (> 120 days) among the three definitions occurred in the most arid and the most humid regions of the tropics. All definitions and datasets consistently showed longer dry seasons in southern Amazon (due to delayed DSE) and central Africa (due to both earlier DSA and delayed DSE). However, definitions that account for changing water demand estimated longer DSL extension over those two regions. These results indicate that warming-enhanced evapotranspiration exacerbates dry season lengthening and ecosystem water deficit. Thus, it is necessity to account for the evolving water demand of tropical ecosystems when characterizing changes in seasonal dry periods and ecosystem water deficits in an increasingly warmer and drier climate.

scholarly journals Development of a management tool for reservoirs in Mediterranean environments based on uncertainty analysis

2012 ◽  
Vol 12 (5) ◽  
pp. 1789-1797 ◽  
Author(s):  
R. Gómez-Beas ◽  
A. Moñino ◽  
M. J. Polo
Keyword(s):  
Uncertainty Analysis ◽  
Water Cycle ◽  
Integrated Management ◽  
Management Tool ◽  
Short Term ◽  
Climate Fluctuations ◽  
The Social ◽  
Reservoir Watershed ◽  
Supply Capacity

Abstract. In compliance with the development of the Water Framework Directive, there is a need for an integrated management of water resources, which involves the elaboration of reservoir management models. These models should include the operational and technical aspects which allow us to forecast an optimal management in the short term, besides the factors that may affect the volume of water stored in the medium and long term. The climate fluctuations of the water cycle that affect the reservoir watershed should be considered, as well as the social and economic aspects of the area. This paper shows the development of a management model for Rules reservoir (southern Spain), through which the water supply is regulated based on set criteria, in a sustainable way with existing commitments downstream, with the supply capacity being well established depending on demand, and the probability of failure when the operating requirements are not fulfilled. The results obtained allowed us: to find out the reservoir response at different time scales, to introduce an uncertainty analysis and to demonstrate the potential of the methodology proposed here as a tool for decision making.

scholarly journals Three new mountain national parks for Uganda

Oryx ◽  
1993 ◽  
Vol 27 (4) ◽  
pp. 214-224 ◽  
Author(s):  
Thomas M. Butynski ◽  
Jan Kalina
Keyword(s):  
National Parks ◽  
Central Africa ◽  
Gorilla Gorilla ◽  
Gorilla Gorilla Gorilla ◽  
East Central ◽  
Albertine Rift ◽  
Gorilla Beringei ◽  
Conservation Values ◽  
Gorilla Gorilla Beringei

For many years the Fauna and Flora Preservation Society has supported efforts to conserve forests in the Albertine Rift Afromontane Region of east-central Africa. The biodiversity of these forests is especially high but most have been destroyed or badly degraded. There are a large number of local, national and international initiatives to conserve at least some of the forests that remain. In 1991 Uganda created the Rwenzori Mountains, Mgahinga Gorilla, and Bwindi-Impenetrable National Parks, thus protecting all three of its Albertine Rift montane forests. This paper presents a synopsis of the conservation values of these three parks, and describes the conservation problems and the efforts to help ensure their proper development and long-term viability. Considerable progress towards the conservation of all three areas has already been made and future prospects are good, particularly for the mountain gorilla Gorilla gorilla beringei.

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