scholarly journals Human Influences on Tree Diversity and Composition of a Coastal Forest Ecosystem: The Case of Ngumburuni Forest Reserve, Rufiji, Tanzania

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
J. Kimaro ◽  
L. Lulandala
Keyword(s):  
Species Diversity ◽  
Forest Ecosystem ◽  
Anthropogenic Activities ◽  
Coastal Forests ◽  
Useful Plants ◽  
Economic Activities ◽  
Forest Reserve ◽  
Disturbed Areas ◽  
Undisturbed Forest ◽  
Ecological Functioning

This paper reports on the findings of an ecological survey conducted in Ngumburuni Forest Reserve, a biodiversity rich forest reserve within the coastal forests of Tanzania. The main goal of this study was to determine the influence of uncontrolled anthropogenic activities on tree species diversity and composition within the forest ecosystem. It was revealed that economic activities including logging, charcoaling, and shifting cultivation were the most important disturbing activities affecting ecological functioning and biodiversity integrity of the forest. Further to this, we noted that the values of species diversity, composition, and regeneration potential within the undisturbed forest areas were significantly different from those in heavily disturbed areas. These observations confirm that the ongoing human activities have already caused size quality degradation of useful plants, enhanced species diversification impacts to the forest ecosystem, and possibly negatively affected the livelihoods of the adjacent local communities. Despite these disturbances, Ngumburuni forest reserve still holds important proportions of both endemic and threatened animal and plant species. The study suggests urgent implementation of several conservation measures in order to limit accessibility to the forest resources so as to safeguard the richness and abundance of useful biodiversity stocks in the reserve.

scholarly journals Analysis of Pattern and Extent of Deforestation in Akure Forest Reserve, Ondo State, Nigeria

2019 ◽  
Vol 12 (1-2) ◽  
pp. 1-11
Author(s):  
Isaac Adelakun Gbiri ◽  
Nathaniel Olugbade Adeoye
Keyword(s):  
Anthropogenic Activities ◽  
Remote Sensing Data ◽  
Satellite System ◽  
Optical Remote Sensing ◽  
Human Beings ◽  
Southwestern Nigeria ◽  
Forest Reserve ◽  
Forest Depletion ◽  
Undisturbed Forest ◽  
The Government

Abstract Forest Reserves in Southwestern Nigeria have been threatened by urbanization and anthropogenic activities and the rate of deforestation is not known. This study examined the vegetation characteristics of Akure Forest Reserve using optical remote sensing data. It also assessed the changing pattern in the forest reserve between 1986 and 2017. Global Navigation Satellite System (GNSS) receiver was used to capture the location of the prominent settlements that surrounded the Forest Reserve in order to evaluate their effects on the forest. Landsat TM 1986, Landsat ETM+ 2002 and Landsat OLI_TIRS 2017 with 30m resolution were classified to assess the spatio-temporal changing pattern of the forest reserve. The results showed different composition of vegetation, which include undisturbed forest, secondary regrowth and farmlands. The study further revealed that in 1986, 2002 and 2017, undisturbed forest constituted 63.3%, 32.4% and 32.1% of the entire land area respectively, while secondary regrowth occupied 8.3% in 1986, 9.5% in 2002 and 15.6% in 2017. The farmlands had erratic growth between 1986 and 2017. It was 16.9% in 1986, 22.1% in 2002 and 17.5% in 2017. The bare ground exhibited inconsistency in the coverage. In 1986 the areal extent was 11.5%, when it increased to 36% in 2002 and decreased to 31.9% in 2017. In conclusion, the study revealed the extent of forest depletion at Akure Forest Reserve and it is therefore important that the residents, the government and the researchers show major concern about some of the critical factors to human beings that are responsible for forest depletion.

Contrasting Diaspore and Vegetation Attributes of Grasses From Natural and Disturbed Habitats in an Urban Eucalypt Forest Reserve

1993 ◽  
Vol 41 (6) ◽  
pp. 637 ◽  
Author(s):  
BM Odgers ◽  
RW Rogers
Keyword(s):  
Grass Species ◽  
Forest Species ◽  
Forest Reserve ◽  
Morphological Attributes ◽  
The Road ◽  
Eucalypt Forest ◽  
Disturbed Areas ◽  
Undisturbed Forest ◽  
Mowing Regime ◽  
Disturbed Habitats

Forty one species of grasses from a eucalypt forest reserve near Brisbane, Australia, were allocated to groups characteristic of undisturbed forest, regularly mown areas, and road banks. Morphological attributes of diaspores, height and growth habit of mature plants, species origin, flowering times and life history were determined for each species. Species characteristic of the mown areas had lighter diaspores than the forest gasses and did not possess awns; if a callus was present it was blunt and did not have antrorse hairs. Species from mown areas also differed from the forest species in being mainly short stoloniferous exotics which flowered for longer than the forest species. Species characteristic of the natural forest and road bank areas had diaspores of similar mass, similar diaspores attributes (awns, callus and antrorse hairs) and species of both habitats were mainly tall and tufted. The road bank species differed from the forest species in being mainly of exotic origin and in flowering for up to 9 months per year longer than the forest species. That grass species of mown areas successfully compete with forest species in mown areas may be because of a mowing regime which selects for short, mainly stoloniferous, species which have longer periods of diaspore production than the forest species. As road banks are not subjected to regular mowing, an extended pattern of flowering which ensures a continuous supply of diaspores may account for road bank species successfully competing with forest species in disturbed areas.

scholarly journals Floristic Composition, Structure, and Species Associations of Dry Miombo Woodland in Tanzania

2014 ◽  
Vol 2014 ◽  
pp. 1-15 ◽  
Author(s):  
Ezekiel Edward Mwakalukwa ◽  
Henrik Meilby ◽  
Thorsten Treue
Keyword(s):  
Species Richness ◽  
Species Diversity ◽  
Forest Structure ◽  
Anthropogenic Activities ◽  
Good Condition ◽  
Floristic Composition ◽  
Woody Species ◽  
Present Species ◽  
Miombo Woodland ◽  
Forest Reserve

For the majority of forest reserves in Tanzania, biodiversity is poorly documented. This study was conducted to assess species richness (woody species), diversity, and forest structure and to examine relationships between species occurrence and topographic and edaphic factors in the Gangalamtumba Village Land Forest Reserve, a dry Miombo woodland area in Tanzania. A total of 35 nested circular plots with radii of 5, 15, and 20 m were used to collect data on woody species and soil samples across the 6,065 ha community-managed forest reserve. Stumps were measured 20 cm above ground. A total of 88 species belonging to 29 families were identified. Generally forest structure parameters and diversity indices indicated the forest to be in a good condition and have high species richness and diversity. Vegetation analysis revealed four communities of which two were dominated by the family Caesalpiniaceae, indicating large variation of site conditions and possible disturbances in the study area. The high level of diversity of woody species and the high basal area and volume indicate that the forest is in good condition, but the effect of anthropogenic activities is evident and stresses the need for proper management to maintain or enhance the present species diversity.

scholarly journals Assessment of species diversity and distribution of woody species on selected plots in Olokemeji Forest Reserve, Ogun State, Nigeria

2021 ◽  
Vol 22 (3) ◽  
pp. 43-50
Author(s):  
D.M. Taiwo ◽  
S.I. Udoh ◽  
S.O. Olaoti-Laaro ◽  
O.R. Jeminiwa ◽  
M.S. Jeminiwa
Keyword(s):  
Species Richness ◽  
Species Diversity ◽  
Woody Species ◽  
Tectona Grandis ◽  
Importance Value ◽  
Forest Reserve ◽  
Lowland Rain Forest ◽  
Ogun State ◽  
The Status ◽  
And Function

The Assessment of forest species composition and species diversity is essential in understanding the status of tree population and diversity for conservation purpose. Olokemeji forest reserve is situated in the lowland rain  forest of south-western Nigeria and it occupies a total land area of 58.88 km2 . Six study plots of 50m2 each were randomly selected and designated as Frequently Burnt Plot 1, Frequently Burnt Plot 2, Harvested Plot, Unharvested Unburnt Plot, Arable Plot 1 and Arable Plot 2 for the purpose of assessment of species diversity and distribution of woody species. Seven species of trees were identified belonging to five families. One hundred and eighty two stands were enumerated, with Unharvested Unburnt Plot having the highest number of trees at 50. The dominance index for the woody flora was 1 in Frequently Burnt Plot 1 and 2 as well as Arable Plot 1 and 2 except for the Harvested Plot that had the lowest (0.29) while the Unharvested Unburnt Plot had 0.75. Highest species richness was recorded at the Harvested Plot at 0.71. The species diversity in Harvested Plot was low (1.54), while it was extremely low in Unharvested Unburnt Plot (0.43). Evenness index was lowest in the Unharvested Unburnt Plot at 0.43. Tectona grandis had the highest relative importance value in the Frequently Burnt Plot 1. The low species richness and species diversity is a direct indication of anthropogenic interference in the study plots and the forest reserve; this requires urgent mitigation to prevent a total loss of its structure and function as expected of a forest reserve. Keywords: Species, Diversity, Evenness, Anthropogenic, Forest, Dynamics

scholarly journals Comparative Analysis of Atmospheric Carbon Dioxide Concentration and Temperature between Forest and Non-Forested Domains in Oyo State, Nigeria

2021 ◽  
Vol 25 (3) ◽  
pp. 445-449
Author(s):  
B.M. Awosusi ◽  
I.S. Adamu ◽  
A.R. Orunkoyi ◽  
D.O. Atiba ◽  
A.A. Obe ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Atmospheric Carbon Dioxide ◽  
Anthropogenic Activities ◽  
Carbon Dioxide Concentration ◽  
High Rate ◽  
Afternoon Session ◽  
Forest Reserve ◽  
Positive Correlation ◽  
Routine Monitoring ◽  
Reduce Carbon Dioxide

This study was carried out to assess the concentration levels of CO2 and temperature and also to correlate their values among selected locations in Oyo State, Nigeria. CO2 and temperature readings were taken using a portable CO2 meter, and a GPS was use to capture co-ordinates of sample points, this was done twice a day. Data were collected from 7am to 11am for morning session while afternoon session data were collected between 1pm and  5pm making a total of 8 hours monitoring. There were negative correlation between CO2 and temperature in all the forests while we have positive correlation between CO2 and temperature in non-forested domains, this,  by implication, means that presence of trees in the forest reserve help to reduce Carbon dioxide during the day since trees  manufacture their food using CO2 in the presence of sunlight. Also, the positive correlation between CO2 and temperature in the towns is due to high rate of human anthropogenic activities during the day. The values of CO2 obtained in this study were higher when  compared with IPCC limit of 435 ppm (parts per million) of CO2 emission. Routine monitoring of carbon dioxide and public education is recommended. Keywords: Carbon dioxide, Temperature, Forest, Non-Forest, Forest Reserve

scholarly journals Biomass and Carbon Stock Estimation of Udawattakele Forest Reserve in Kandy District of Sri Lanka

2019 ◽  
Vol 8 (2) ◽  
Author(s):  
A.M.S.K. Abeysekara ◽  
S.K. Yatigammana ◽  
K.T. Premakantha
Keyword(s):  
Carbon Dioxide ◽  
Sri Lanka ◽  
Carbon Stock ◽  
Anthropogenic Activities ◽  
Terrestrial Ecosystem ◽  
Total Carbon ◽  
Total Biomass ◽  
Moderate Amount ◽  
Forest Reserve ◽  
Rate Of Increase

Carbon dioxide has gained lot of attention in recent past as a greenhouse gas, and therefore it has a potential to affect the climate pattern of the world. Several anthropogenic activities are known to be responsible for the increased level of carbon in the atmosphere and disruption of the global carbon cycle. However, nature has its own mechanism of sequestering and storing the carbon in its “reservoirs”. Forest has the ability to sequester carbon in their biomass and reduce the rate of increase of atmospheric carbon dioxide. The carbon sequestered in the forest trees are mostly referred to as the biomass of a tree or a forest. It has been identified five carbon pools of the terrestrial ecosystem, involving biomass. The study was designed to estimate biomass stock and then the carbon stock of the Udawattakele Forest Reserve (7°17'58 "N, 80°38'20’’E) in Kandy, Sri Lanka. Allometric equations were used to calculate biomass of trees. The total biomass stock was estimated to be 9475.56 t ha-1 (Mega gram-Mg) and the total carbon stock was estimated to be 4,453.55 t ha-1 (Mg) in the Udawattakele Forest Reserve (UFR). This amount is equivalent to 16,344.52 Mg of carbon dioxide in the atmosphere. UFR holds a moderate amount of biomass/carbon stock and the total carbon density of natural forest and plantations was found to be 36.55 Mg ha-1 and 44.89 Mg ha-1 respectively.

Impacts of COVID-19 lockdown strategies on NOx, CO and CO2 surface observations on two megacities: focus on the traffic sector in Mexico City (Mexico) and Paris (France)

2021 ◽  
Author(s):  
Sophie Tran ◽  
Michel Ramonet ◽  
Thomas Lauvaux ◽  
Philippe Ciais ◽  
Olivier Laurent ◽  
...  
Keyword(s):  
Mexico City ◽  
Road Traffic ◽  
Anthropogenic Activities ◽  
Atmospheric Dispersion ◽  
Monitoring Network ◽  
Economic Activities ◽  
Capital Cities ◽  
Pollutant Concentrations ◽  
Travel Restrictions ◽  
Co Concentrations

<p><span>In 2020, the COVID-19 pandemic imposed countries to apply stringent policies to slow down the spread of the SARS-CoV-2 virus. During the Spring time, most countries had announced a national lockdown that had important consequences on many capital cities such as Mexico City and Paris. The shutdown of many of these economic activities had a direct impact on the traffic sector. Travel restrictions led to a drastic decrease of major air pollutants in those two cities. From each local air quality monitoring network, we discriminated background, urban and traffic sites. By looking at the differences between urban sites versus background sites, we observed in Mexico City a decrease of 51%, 58 % and 44 % for </span><span>Δ</span><span>NO</span><sub><span>x</span></sub><span>, </span><span>Δ</span><span>CO</span><sub><span>2</span></sub><span> and </span><span>Δ</span><span>CO concentrations, respectively, during the lockdown. Markedly, their concentrations remained below typical levels after the end of the lockdown until September. Then, from September to the end of the year, the pollutants concentrations increased back to the same level as before the lockdown. The same behavior was seen at Paris. During the spring lockdown period, we observed a decrease of 72 %, 70 % and 88 % for </span><span>Δ</span><span>NO</span><sub><span>x</span></sub><span>, </span><span>Δ</span><span>CO</span><sub><span>2</span></sub><span> and </span><span>Δ</span><span>CO concentrations, respectively. Until the end of the summer, the concentrations of those pollutants remained at the same level as during the lockdown. From September, we observed an increase of pollutants concentrations to the levels of previous years. </span></p><p><span>Despite road traffic increases by the end of the lockdown in both megacities, the remainly low concentrations seen for those pollutants until September might be an effect of the atmospheric dispersion combined with a slow reactivation of anthropogenic activities. Nevertheless, a second lockdown period imposed in France (from Oct. 30 to Dec. 15) have clearly not shown the same impact on pollutant concentrations as the first one exhibited. On the contrary, no significant changes in pollutant concentrations were observed during the second lockdown, and moreover, peaks of </span><span>Δ</span><span>NO</span><sub><span>x</span></sub><span>, </span><span>Δ</span><span>CO</span><sub><span>2</span></sub><span> and </span><span>Δ</span><span>CO concentrations were seen during the last weekends of the lockdown of up to 32 % of increase, compared to the weekday-level during the 2nd lockdown. This can be explained by less stringent travel restrictions combined with pre-Christmas preparations in Paris. </span></p>

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