Influence of tree species and compass bearing on insect folivory of nine common tree species in the West African savanna

Levels of leaf damage due to insect folivory have been investigated in forests of different latitudes all over the world, but most research has concentrated on a few common forest types. Most studies of insect herbivory were conducted in (sub)tropical rain forests (Barone 1998, Basset 1996, Coley 1983, Lowman 1985), or in temperate forests (Landsberg & Ohmart 1989, Lowman & Heatwole 1992). In contrast, little is known about insect folivory of woody plants in tropical savannas (Fowler & Duarte 1991, Marquis et al. 2001, Ribeiro 2003, Stanton 1975), and no such data are available for the West African savanna ecosystem (Andersen & Lonsdale 1990). Savannas cover about 40% of the land surface of Africa and 20% of the world (Scholes & Walker 1993), and savanna trees may host considerable numbers of insects, including many herbivores (Grant & Moran 1986, Mody et al. 2003). Therefore, insect herbivory can be considered a potentially important aspect of plant–animal interactions for vast areas of tropical ecosystems, where it has been studied remarkably rarely so far.

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Sensitivity study of the regional climate model RegCM4 to different convective schemes over West Africa

Earth System Dynamics ◽

10.5194/esd-9-1261-2018 ◽

2018 ◽

Vol 9 (4) ◽

pp. 1261-1278 ◽

Cited By ~ 7

Author(s):

Brahima Koné ◽

Arona Diedhiou ◽

N'datchoh Evelyne Touré ◽

Mouhamadou Bamba Sylla ◽

Filippo Giorgi ◽

...

Keyword(s):

West Africa ◽

Land Surface ◽

West African ◽

Cold Bias ◽

The West ◽

Land Surface Scheme ◽

African Climate ◽

Sensitivity Studies ◽

Surface Scheme ◽

Convective Scheme

Abstract. The latest version of RegCM4 with CLM4.5 as a land surface scheme was used to assess the performance and sensitivity of the simulated West African climate system to different convection schemes. The sensitivity studies were performed over the West African domain from November 2002 to December 2004 at a spatial resolution of 50 km × 50 km and involved five convective schemes: (i) Emanuel; (ii) Grell; (iii) Emanuel over land and Grell over ocean (Mix1); (iv) Grell over land and Emanuel over ocean (Mix2); and (v) Tiedtke. All simulations were forced with ERA-Interim data. Validation of surface temperature at 2 m and precipitation were conducted using data from the Climate Research Unit (CRU), Global Precipitation Climatology Project (GPCP) and the Tropical Rainfall Measurement Mission (TRMM) during June to September (rainy season), while the simulated atmospheric dynamic was compared to ERA-Interim data. It is worth noting that the few previous similar sensitivity studies conducted in the region were performed using BATS as a land surface scheme and involved less convective schemes. Compared with the previous version of RegCM, RegCM4-CLM also shows a general cold bias over West Africa whatever the convective scheme used. This cold bias is more reduced when using the Emanuel convective scheme. In terms of precipitation, the dominant feature in model simulations is a dry bias that is better reduced when using the Emanuel convective scheme. Considering the good performance with respect to a quantitative evaluation of the temperature and precipitation simulations over the entire West African domain and its subregions, the Emanuel convective scheme is recommended for the study of the West African climate system.

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Mineral fertilizer management of maize on farmer fields differing in organic inputs in the West African savanna

Field Crops Research ◽

10.1016/j.fcr.2005.08.004 ◽

2006 ◽

Vol 96 (2-3) ◽

pp. 355-362 ◽

Cited By ~ 47

Author(s):

M.C.S. Wopereis ◽

A. Tamélokpo ◽

K. Ezui ◽

D. Gnakpénou ◽

B. Fofana ◽

...

Keyword(s):

Mineral Fertilizer ◽

West African ◽

Fertilizer Management ◽

The West ◽

African Savanna

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Food Production in the Forest Zone of West Africa: Archaeological and Historical Perspectives

Oxford Research Encyclopedia of African History ◽

10.1093/acrefore/9780190277734.013.139 ◽

2017 ◽

Author(s):

Richard T. Chia ◽

A. Catherine D'Andrea

Keyword(s):

West Africa ◽

Oil Palm ◽

Tree Species ◽

Food Production ◽

West African ◽

Before Present ◽

The West ◽

Forest Zone ◽

Historical Perspectives ◽

Indigenous Tree Species

Recent narratives on the origin of food production in the West African forest zone have replaced earlier diffusion-based models with viewpoints that emphasize the diversity of sources for plants and animals exploited and domesticated in the region. Management of indigenous tree species, including oil palm and incense tree, managed first by indigenous foragers, have the longest history in the area, dating back to over 8,400 before present (bp). After the 4th millennium bp, domesticates such as pearl millet, cowpea, and domestic caprines were introduced from adjacent Sahel and the savanna regions, and populations began to favor oil palm over incense tree. The mechanisms of these introductions are less clear but likely involved both diffusion and/or movements of peoples who became sedentary to varying degrees. Palaeoenvironment is an important factor to consider in tracking the development of food production in the forest zone; however, some combination of natural and human-mediated changes took place, the nature of which was not uniformly distributed.

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Is the diversity of the Beach Flies adequately known? Some notes on the state of the art of current knowledge (Diptera: Canacidae)

Bollettino della Società Entomologica Italiana ◽

10.4081/bollettinosei.2015.99 ◽

2015 ◽

pp. 99-111

Author(s):

Lorenzo Munari

Keyword(s):

Bay Of Bengal ◽

State Of The Art ◽

Current Knowledge ◽

Neotropical Region ◽

West African ◽

The State ◽

South American ◽

The West ◽

Scientific Institutions ◽

The World

An overview of the major zoogeographical gaps in our knowledge of the world beach flies (subfamilies Apetaeninae, Horaismopterinae, Pelomyiinae, and Tethininae) is provided. The identified areas treated in this work are as follows: the subarctic Beringia, the South American circum-Antarctic islands, the Neotropical Region south of the equator, most of the West African seacoasts, the huge area ranging from India, across the Bay of Bengal, to Sumatra and Java, and most of Australia. Apart from the inhospitable northernmost and southernmost areas of the planet, which feature a real very low biodiversity, the remaining vast areas dealt with in this work woefully suffer a dramatic paucity of field collections, as well as of previously collected materials preserved in scientific institutions. This might seem a truism that, however, must be emphasized in order to unequivocally identify the geographic areas that need to be further investigated

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The Environmental Effects of Policy Change in the West African Savanna: Resettlement, Structural Adjustment and Conservation in Western Mali

Journal of Political Ecology ◽

10.2458/v5i1.21396 ◽

1998 ◽

Vol 5 (1) ◽

pp. 23 ◽

Cited By ~ 6

Author(s):

Dolores Koenig ◽

Tiéman Diarra

Keyword(s):

Structural Adjustment ◽

Study Data ◽

West African ◽

The West ◽

African Savanna ◽

Policy Initiatives ◽

River Basin Development ◽

Case Study Data ◽

Simultaneous Implementation

This article broadens analytic perspectives on the effects of government interventionsby looking at the interaction of two distinct but simultaneous policy initiatives: involuntary resettlement and structural adjustment. Case study data from the Bafing valley in Mali show that simultaneous implementation of these two initiatives reinforced the economic growth of the zone but increased negative environmental effects.Key Words: Mali, resettlement, structural adjustment, sahel, environmental degradation, economic development, river basin development, privatization, liberalization.

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Spatial carbon, nitrogen and phosphorus budget of a village in the West African savanna—I. Element pools and structure of a mixed-farming system

Agricultural Systems ◽

10.1016/s0308-521x(03)00053-2 ◽

2004 ◽

Vol 79 (1) ◽

pp. 55-81 ◽

Cited By ~ 23

Author(s):

Raphaël J. Manlay ◽

Alexandre Ickowicz ◽

Dominique Masse ◽

Christian Floret ◽

Didier Richard ◽

...

Keyword(s):

Farming System ◽

West African ◽

Nitrogen And Phosphorus ◽

The West ◽

African Savanna ◽

Phosphorus Budget ◽

Mixed Farming

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Of Trees and Earth Shrines: An Interdisciplinary Approach to Settlement Histories in the West African Savanna

History in Africa ◽

10.2307/3172212 ◽

2001 ◽

Vol 28 ◽

pp. 139-168 ◽

Cited By ~ 9

Author(s):

Carola Lentz ◽

Hans-Jürgen Sturm

Keyword(s):

Burkina Faso ◽

Natural Environment ◽

Interdisciplinary Approach ◽

West African ◽

The West ◽

African Savanna ◽

Frankfurt Am Main ◽

Lake Chad ◽

History Of ◽

To Come

For a vegetation geographer and an anthropologist to come together to write on the settlement histories of segmentary societies in the West African savanna is unusual or at least rare. A few words on the origin of this cooperation therefore seem appropriate. For over ten years, in the context of an interdisciplinary research program at the Universität Frankfurt am Main, archeologists, anthropologists, linguists, botanists and geographers have been working together on the history of cultures, languages, and natural environment of the West African savanna, especially the interaction between human activity and the natural environment. That one should actually be speaking in many cases of a culturally mediated “landscape” rather than a “natural environment” is one of the outcomes of the research projects, which have focused mainly on different regions of Burkina Faso (in the sahel and Sudanese zone) and the Lake Chad area of northeast Nigeria.The present paper has emerged from a botanical and an anthropological-historical project on the history of vegetation and of settlement in south and southwest Burkina Faso. This history has been shaped by the great expansion of the Dagara-speaking population. In the last two hundred years (possibly longer), small groups of Dagara patrilineages, related and allied to one another, have migrated north and northwest, probably from the region around Wa in present-day Ghana, and have founded numerous new settlements—a process of land appropriation that is still going on today, though with changed circumstances regarding land rights (see map 1).

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