Spatial Distribution of Pterocarpus erinaceus Poir. (Fabaceae) Natural Stands in the Sudanian and Sudano-Guinean Zones of West Africa: Gradient Distribution and Productivity Variation across the Five Ecological Zones of Togo

2015 ◽  
Vol 6 (2) ◽  
pp. 89-102 ◽  
Author(s):  
Segla Novinyo ◽  
Adjonou Kossi ◽  
Rabiou Habou ◽  
Radji Raoufou ◽  
Kokutse Dzifa ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
West Africa ◽  
Gradient Distribution ◽  
Ecological Zones ◽  
Pterocarpus Erinaceus ◽  
Natural Stands

scholarly journals Vulnerability of African Rosewood (Pterocarpus erinaceus, Fabaceae) natural stands to climate change and implications for silviculture in West Africa

Heliyon ◽  
2020 ◽  
Vol 6 (6) ◽  
pp. e04031
Author(s):  
Kossi Adjonou ◽  
Komla Elikplim Abotsi ◽  
Kossi Novinyo Segla ◽  
Habou Rabiou ◽  
Towanou Houetchegnon ◽  
...  
Keyword(s):  
Climate Change ◽  
West Africa ◽  
Pterocarpus Erinaceus ◽  
Natural Stands

scholarly journals Effect of nursery substrate on the growth of Pterocarpus erinaceus Poir. seedlings

2021 ◽  
Vol 8 (9) ◽  
pp. 17-27
Author(s):  
ALABA Pyoabalo ◽  
Atti TCHABI ◽  
Komla Elikplim ABOTSI ◽  
Kossi ADJONOU ◽  
Kossi Novinyo SEGLA ◽  
...  
Keyword(s):  
West Africa ◽  
Soil Microorganisms ◽  
High Pressures ◽  
Production Constraints ◽  
Pterocarpus Erinaceus ◽  
Number Of Leaves ◽  
The Mean ◽  
Negative Impacts ◽  
Natural Stands ◽  
Positive Effect

The high pressures on Pterocarpus erinaceus Poir. severely affect its natural stands in West Africa. The measures taken to reverse this trend are still inefficient due to plantlets production constraints. This study aims to understand the importance of growing substrates on seedlings growth in nursery. Composite soil samples were collected at 20 cm depth from 4 seed trees in 5 different sites in Togo (West Africa). Two batches were made for each site, one of which was sterilized by autoclave and the other has received no treatment. Three growing parameters (length of stem, number of buds and number of leaves) of the plantlets obtained from sterilized seeds were measured during 20 weeks in the nursery. Results show for each site a significantly better growing rate of seedlings on unsterilized substrates, compared to sterilized substrates. At the end of the experiment, plantlets were 8.75 ± 2.32 cm mean height on sterilized substrates when they reach 19.20 ± 5.00 cm on unsterilized substrates. The mean number of buds and leaves per plantlet varies from 2.23 ± 1.71 buds and 3.00 ± 1.86 leaves to 10.73 ± 3.28 buds and 11.09 ± 2.48 leaves at the same date, respectively on sterilized and unsterilized substrates. The low growing rate on sterilized substrates should be linked to the low capacity of plantlets in mobilizing phosphorus, potassium and nitrogen without microorganisms. Negative impacts of sterilization were highlighted on seedlings by necrosis of buds and leaves from the 7th week of growth, demonstrating a positive effect of soil microorganisms on the proper development of the seedlings.

Population structure of Pterocarpus erinaceus Poir. across a protection gradient in Sudanian savannahs of Togo, West Africa

2018 ◽  
Vol 57 (1) ◽  
pp. 104-112 ◽  
Author(s):  
Tèkondo Banla ◽  
Thierry D. Houehanou ◽  
Merveille Koissi Savi ◽  
Rodrigue Idohou ◽  
Romain Glèlè Kakaï ◽  
...  
Keyword(s):  
Population Structure ◽  
West Africa ◽  
Pterocarpus Erinaceus

scholarly journals Characteristics and Influencing Factors of Spatial Differentiation of Urban Black and Odorous Waters in China

2018 ◽  
Vol 10 (12) ◽  
pp. 4747 ◽  
Author(s):  
Guolei Chen ◽  
Jing Luo ◽  
Chunyan Zhang ◽  
Liang Jiang ◽  
Lingling Tian ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Sewage Treatment ◽  
Water Environment ◽  
Spatial Differentiation ◽  
Urban Pollution ◽  
Influential Factors ◽  
Joint Control ◽  
Chinese Government ◽  
Analysis Tool ◽  
Gradient Distribution

The pollution problem caused by urban black and odorous waters has received much attention from the Chinese government. Our research aims at systematically identifying the characteristics and the influential factors of spatial differentiation of urban black and odorous waters across China. The research, based on the data of black and odorous waters from 2100 Chinese cities, was conducted with the spatial analysis tool of ArcGIS. We found that the amount of Chinese urban black and odorous waters varied in spatial distribution, which was an agglomerated type with significant agglomeration. The kernel density was characterized by independent single kernel centers with ribbon-like and sporadic distributions of subcenters. The cold and hot spots showed a gradient distribution pattern of cold in the southwest and hot in the central east. These spatial distribution characteristics could be attributed to the following core factors, total wastewater discharge, length of urban drainage pipelines, municipal solid waste collection, daily urban sewage treatment capacity, and investment in urban pollution treatment of wastewater. The findings reveal the current geospatial distribution of black and odorous waters pollution and provide reference for the Chinese government to treat the pollution from several key points. Lastly, it is suggested that the Chinese government should establish joint control, joint prevention, and joint treatment mechanisms in the black and odorous waters areas and improve the safety standards of the whole water environment, so as to promote the treatment and elimination of urban black and odorous waters.

scholarly journals Temporal and spatial distribution of anthrax outbreaks among Kenyan wildlife, 1999–2017

2019 ◽  
Vol 147 ◽  
Author(s):  
J. M. Gachohi ◽  
F. Gakuya ◽  
I. Lekolool ◽  
E. Osoro ◽  
L. Nderitu ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Infectious Diseases ◽  
Disease Surveillance ◽  
Wildlife Conservation ◽  
Conservation Areas ◽  
Temporal And Spatial Distribution ◽  
Ecological Zones ◽  
Herbivore Species ◽  
Multiple Species

Abstract The burden of anthrax in wildlife is demonstrated through high numbers of sudden mortalities among herbivore species, including endangered animal species. East Africa is home of multiple species of faunal wildlife numbering in the millions but there are limited disease surveillance programmes, resulting in a paucity of information on the role of anthrax and other infectious diseases on declining wildlife populations in the region. We reviewed historical data on anthrax outbreaks from Kenya Wildlife Service (KWS) spanning from 1999 to 2017 in Kenya to determine the burden, characteristics and spatial distribution of anthrax outbreaks. A total of 51 anthrax outbreaks associated with 1014 animal deaths were reported across 20 of 60 wildlife conservation areas located in six of the seven agro-ecological zones. Overall, 67% of the outbreaks were reported during the dry seasons, affecting 24 different wildlife species. Over 90% (22 of 24) of the affected species were herbivore, including 12 grazers, five browsers and five mixed grazers and browsers. Buffaloes (23.5%), black rhinos (21.6%) and elephants (17.6%) were the most frequently affected species. Our findings demonstrate the extensive geographic distribution of wildlife anthrax in the country, making it one of the important infectious diseases that threaten wildlife conservation.

Seed dispersal, spatial distribution and population structure of Brazilnut trees (Bertholletia excelsa) in southeastern Amazonia

1997 ◽  
Vol 13 (4) ◽  
pp. 595-616 ◽  
Author(s):  
Carlos A. Peres ◽  
Claudia Baider
Keyword(s):  
Spatial Distribution ◽  
Seed Dispersal ◽  
Average Distance ◽  
Climatic Conditions ◽  
Long Distance ◽  
Neotropical Forests ◽  
Bertholletia Excelsa ◽  
Entire Study ◽  
Natural Stands ◽  
Seed Shadows

ABSTRACTSeeds of the Brazilnut tree (Bertholletia excelsa Humb. & Bonpl., Lecythidaceae) sustain one of the most important extractive industries in neotropical forests. Yet little is known about the demography and seed dispersal ecology of Bertholletia, particularly in natural stands which have not been previously harvested. This study presents data on the population density, spatial distribution, and seed dispersal ecology of Brazilnut trees at a pristine stand located within the Kayapó Indian Area of southeastern Amazonia, Pará, Brazil. Brazilnut trees were primarily found within groves (castanhais) of 75 to 149 trees, with a few isolated trees in between. Although the density of trees ≥ 10 cm in diameter at breast height (hereafter, dbh) at two groves was 4.8 to 5.1 trees ha–1, the overall density for the entire study area of c. 950 ha was estimated at 1.3 tree ha–1. Within-grove nearest neighbour distances averaged 21 m and were markedly skewed towards even shorter distances. Seed dispersal experiments using 709 marked seeds indicated that this pattern can be largely explained by the highly restricted seed shadows imparted by the main seed dispersal agents of Bertholletia at this site, the red-rumped agouti (Dasyprocta leporina). Agoutis on average scatterhoard Bertholletia seeds to an average distance of 5 m, and rarely beyond 20 m, from seed stations. We suggest that, once edaphic and climatic conditions are suitable, the highly contagious spatial distribution of Bertholletia trees at the landscape level can be largely accounted for by the quantitatively dominant effect of short-distance dispersal by caviomorph rodents, and rare events of long-distance dispersal provided by other vectors. This mechanism of grove formation need not resort to untested conjectures of human dispersal and intentional planting in prehistoric and historic times as it has often been suggested in the literature.

Sign in / Sign up

Export Citation Format

Share Document