Open Journal of Forestry
ISSN / EISSN : 2163-0429 / 2163-0437
Current Publisher: Scientific Research Publishing, Inc. (10.4236)
Total articles ≅ 351
Latest articles in this journal
Open Journal of Forestry, Volume 11, pp 37-46; doi:10.4236/ojf.2021.111003
This study aims to estimate the tree diversity status of Rashad Forest Reserves in the Rashad locality of the South Kordofan State of Sudan. For data collection, eight sample plots (20 × 20 m) were taken randomly, and parameters were determined: trees species diversity, composition, relative density, dominance, important value index, and species richness in the Rashad forest reserve. The results show that a total of 237 and 56 tree species, including 22 families, have been identified in the study area. Fabaceae family and species numbers have the highest number of 13 species in 8 genera, followed by Combretaceae with 8 species belonging to 3 different genera, Malvaceae with 5 species belonging to 4 different genera, Apocynaceae with 3 species belonging to 3 different genera. The Arecaceae, Burseraceae, Capparaceae, Euphorbiaceae, Meliaceae, and Rubiaceae families each had two species, and all the other 11 families had one species each. Among the 56 different tree species found within the reserve. The results also indicated that Tamarindus indica L. and Ziziphus spina-christi (L.) Desf. had the highest relative density and dominance of 4.64% and 11% respectively. Adansonia digitata L., Grewia villosa Willd, Vepris nobilis (Delile) Mziray had density and dominance of 4.80% and 9%. Followed by Anogeissus leiocarpa (DC.) Guill. & Perr, Adansonia digitata L., Catunaregam nilotica (Stapf) Tirveng. (Syn: Xeromphis nilotica (Stapf) Keay, Vangueria madagascariensis J. F. Gmel. with 3.38% and 8%, respectively. Eleven species recorded the least relative dominance of 0.42%. Shannon-Weiner diversity index (H’) value stood at 3.82. And as diversity indices varied with location depending on the species available within an ecological zone, Rashad forest reserve is blessed with a moderate diversity index.
Open Journal of Forestry, Volume 11, pp 47-60; doi:10.4236/ojf.2021.111004
Canopy density and forest biomass estimation are critical for understanding of the carbon cycle, climate change and detecting health status of the forest ecosystems. This study was conducted on the coastal forests reserves in Zanzibar and mainland Tanzania. A systematic sampling design was used to establish a total of 110 temporary sample plots in all study sites. The stratification of the forests was adopted to identify closed forest patches with less anthropogenic effects. The study assessed the forest canopy density and above ground biomass with relative carbon stock for closed forest classes. Jozani Chwaka Bay National Park in Zanzibar recorded higher average canopy densities of 63% followed by Ngezi (46%), Pugu forests (26%) and Kazimzumbwi (16%). However, Ngezi forest had higher forest biomass than all study sites with the overall mean AGB of 138.5 tAGB/ha equivalent to carbon stock of 67.9 tC/ha. Tree species, Bombax rhodognaphala (Msufi mwitu) and Antiaris toxicaria (Mgulele) recorded the highest biomass of 1099 tABG/ha and 703 tAGB/ha (equivalent to 538 tC/ha and (345 tC/ha)) respectively. The study revealed that about 35% of the total closed forest patches at Pugu FR were covered by lower canopy density which accounted about 490 ha. Kazimzumbwi FR was dominated by lower canopy density which represented about 64% of the total forest cover area (1750 ha).
Open Journal of Forestry, Volume 11, pp 14-36; doi:10.4236/ojf.2021.111002
Coverage of nominal 95% confidence intervals of a proportion estimated from a sample obtained under a complex survey design, or a proportion estimated from a ratio of two random variables, can depart significantly from its target. Effective calibration methods exist for intervals for a proportion derived from a single binary study variable, but not for estimates of thematic classification accuracy. To promote a calibration of confidence intervals within the context of land-cover mapping, this study first illustrates a common problem of under and over-coverage with standard confidence intervals, and then proposes a simple and fast calibration that more often than not will improve coverage. The demonstration is with simulated sampling from a classified map with four classes, and a reference class known for every unit in a population of 160,000 units arranged in a square array. The simulations include four common probability sampling designs for accuracy assessment, and three sample sizes. Statistically significant over- and under-coverage was present in estimates of user’s (UA) and producer’s accuracy (PA) as well as in estimates of class area proportion. A calibration with Bayes intervals for UA and PA was most efficient with smaller sample sizes and two cluster sampling designs.
Open Journal of Forestry, Volume 11, pp 1-13; doi:10.4236/ojf.2021.111001
It was elaborated a method of agro-ecosystem ranking for feijoa culture and forest ecosystem in one of regions of Western Georgia—Adjara subtropical humidified zone. On the basis of mineralogical and morphometric analysis (biometric parameters, beginning and end of growth, beginning of fruit ripening and mass ripening, frost resistance etc.) of feijoa culture (Feigoa selliowiana) and by multiple-factor approach we have evaluated culture’s rational disposition and optimal environment for development of land. The main accent was made on geomorphological (relief, inclination, exposition) and agro-climatic (sum of active temperatures, hydrothermal coefficient, temperature conditions, physical and chemical features of soil) factors. As a result of implemented zoning a landscape zone with agricultural resources potential and hypsometrical levels optimal for development of feijoa culture was revealed. During the research we also revealed corresponding agro-eco- system zone, compatible with feijoa zone, evaluation of quality of forest land and determination of ecosystem and its indicating character. For determination of compatibility of feijoa plants and distribution of forest ecosystem we have created a map of large-scale ecosystems and geo-information system. By Cartometric and geographic-informational analysis, it became possible to find information about types of forest ecosystems, areas occupied by them and their share in researched zone.
Open Journal of Forestry, Volume 11, pp 61-72; doi:10.4236/ojf.2021.111005
Dynamic urbanization of African cities has created development trajectories that face systemic challenges in the provision of sustainable and ecologically resilient urban environments. The specific challenges include extensive unregulated growth with informal settlements reflecting poor service levels and high poverty indices, inadequacy in provision of basic services in health, water, housing, transport and communication infrastructure, high reliance on biomass fuels, exposure to environmental stress and implausible climate change coping and mitigation mechanisms among others. Review of extensive literature and synthesis of existing bodies of knowledge on the ecological and management perspectives of urban environments revealed many gaps and understanding of urban transformation processes. The purpose of this review was to contextualize credible pathways for optimization of both ecosystem goods and services from green urban landscapes (Green infrastructure) and non-green infrastructure to ensure sustainable and ecologically resilient urban environments. Attempts were made to rationalize and validate through discussions the benefits of managed urban ecosystems for African cities. On the basis of the evidence from the literature, it is concluded that urban development trajectories that do not embrace multifaceted approaches that deliberately retain and maintain green infrastructure in the urban environment may not be cost-effective. It is recommended that systematic integration of urban forestry concepts in urban planning that involves communities, local and national governments, business entrepreneurs and public and private research institutions provides tenable frameworks for addressing current and future challenges of urbanization in Africa.
Open Journal of Forestry, Volume 10, pp 377-387; doi:10.4236/ojf.2020.104023
Tree growth is affected by environmental factors, climate condition and tree age. The objective of this study was to evaluate the growth patterns of Chamaecyparis obtusa (C. obtusa) stand in the Gyeongnam province. Data was collected from two cities and one county by using sample quadrats of 20 * 20 m. A total of 11 quadrats were used to collect tree height, diameter at the breast height (DBH), annual growth rings and soil data. The data analysis of soil moisture content, pH, organic matter (%), EC (cmol + /kg of soil), and available phosphorous was conducted. Growth ring was analyzed by using computer based software and the ages of the trees were identified. Average growth of height and DBH was computed from the surveyed data and annual growth of each tree was assessed by computer based reading of annual growth rings. The results of the study revealed that tree growth showed a reducing trend along the longevity. It was identified that soil pH, age, variation in annual average temperature, and altitude were the main factors related with growth of C. obtusa trees along the life of the stand.
Open Journal of Forestry, Volume 10, pp 445-459; doi:10.4236/ojf.2020.104028
The habitat structure and floristic composition examined for this study are of great importance, providing a scientific baseline of information for developing a biodiversity database and in supporting crucial information for the management decision-making process of the buffer zones. The primary objective of this study was to examine the current status of species composition and stand structure of moist evergreen forests distributed in the TNR buffer zone. Forest inventory was conducted in the primary moist evergreen forest (~1 ha) and secondary moist evergreen forest (~1 ha). In the TNR buffer zone, 83 species belonging to 31 families in the primary moist evergreen forest and 86 species belonging to 32 families in the secondary moist evergreen forest were found. The most dominant families in the primary moist evergreen forest were Dipterocarpaceae, Sapindaceae, Meliaceae, Myrtaceae, and Myristicaceae; at species level; this forest was composed of Nephelium lappaceum, Myristica malabarica, Nephelium laurium, Aglaia andamanica, and Diospyros peregrine. The most dominant families in the secondary moist evergreen forest were Myrtaceae, Sapindaceae, Euphorbiaceae, Myristicaceae, and Lauraceae, while Nephelium lappaceum, Syzygium claviflorum, Syzygium sp-1, Eugenia oblate, and Myristica angustifolia were the most dominant at the species level. The results of S?rensen’s similarity index based on common species (Ks) and the similarity index based on species dominance (Kd) were observed at about 55% and 75% between the primary and secondary moist evergreen forests. The basal area (51.39 m2.ha-1) of the primary moist evergreen forest was higher than that (44.50 m2.ha-1) of the secondary moist evergreen forest. Between these two forest types, the Shannon-Wiener, the Simpson and the Evenness indices were not significantly different at (p ere 910 (±184) and 991 (±183). ?
Open Journal of Forestry, Volume 10, pp 412-427; doi:10.4236/ojf.2020.104026
The Oak Ridge National Laboratory (ORNL) is the largest and most diverse energy, research, and development institution within the Department of Energy (DOE) system in the United States. As such, the site endures constant land development that creates rigorous growing conditions for urban vegetation. Natural resource managers at ORNL recognize that trees are an integral component of the landscape and are interested in characterizing the urban forest and their associated ecosystem services benefits. We evaluated the urban forest structure, quantified ecosystem services and benefits, and estimated economic value of resources using i-Tree Eco at ORNL. While this assessment captured over 1100 landscape trees, the ORNL Natural Resources Management for landscape vegetation can be expanded to include unmanaged landscapes, e.g. riparian areas, greenspace, and other vegetative attributes to increase ecosystem services benefits. Assigning a monetary value to urban forest benefits help to inform decisions about urban forest management, ideally on cost-benefit analysis.
Open Journal of Forestry, Volume 10, pp 232-263; doi:10.4236/ojf.2020.102016
This study was conducted within a distance of three to five kilometres around Lake Burigi as a study area in the Burigi-Chato National Park for the purpose of documenting the diversity of plants, identifying invasive and rare species for enhancing conservation in the park. Lake Burigi was purposively sampled as a study area for plant identification due to its potential as a tourist destination. No study has been conducted in the study area to reveal plants diversity, with a focus on documenting invasive and rare species, thus necessitating undertaking of this study to inform the park authority to take urgent control measures in avoiding widespread invasive species and proper planning for conservation rare species. The methods involved included field observation; plant identification using field guide books, indigenous and professional knowledge; field mapping using GPS receiver and literature reviews. Meteorological data were analysed using Microsoft Excel and SPSS v.20 to determine the relationship between variables. A total of 102 plant species of different growth forms of trees, shrubs, grasses, sedges, forbs, and herbs were identified and recorded. Tegetes minuta and Argemone mexicana were recorded as invasive plant species, while six rare plant species potential for pharmaceutical industry; Zanthoxylum usambarense, Gardenia ternifolia, Faidherbia albida, Harrisonia abyssinica, Anona senegalensis, and, Pappea capensis were also recorded. Scars of wildfires were observed in the study area. The study area received an average rainfall of 964.36 mm per year, the highest peak recorded in 1951. The trend of rainfall showed that many years had rainfall below the average while the temperature was found to increase from year to year, the situation which suggests the existence of climate change in the study area. There was a weak negative relationship between temperature and wind speed. Soil nutrients and disturbances in the area were found to favour the growth of Tegetes minuta. Findings of this study would help ecological unit in the park to conduct regular ecological assessment for the purpose of controlling invasive plant species, which if left to flourish are likely to reduce habit suitability for ungulates to utilize the area. Moreover, knowing which plant species are rare, adds value to the area as a destination to visitors interested by plants. The findings also allow the park authority to keep record of species rarity and thus easily take control of them to avoid unintended exploitation. Based on the findings, it was concluded that a number of disturbances, meteorological and edaphic factors favour the growth of invasive species. Urgent measures are to be taken to control the observed invasive plant species before they are left to spread in the park to avoid destruction of the habitat suitability and incurring unnecessary expenses and time in combating them. Furthermore, rare plant species especially those with pharmaceutical and industrial values are to be conserved with special attention to ensure their continued survival. It was recommended that human-induced activities should be prevented through regular ecological assessment, field patrols and public awareness programs. A similar study needs to be conducted during dry season to make comparison of the capacity of plants in adapting to different changes of the weather.
Open Journal of Forestry, Volume 10, pp 277-292; doi:10.4236/ojf.2020.103018
Non-timber forest products provide important socio-economic services to different village and urban communities in West Africa. However, little is known about the links between the different actors and their contribution to the local or national economy. This study was conducted in central southern Niger and aimed to 1) identify and map the main actors in the value chain of Ziziphus mauritiana and Balanites aegyptiaca fruits; and 2) analyse the silvicultural and socio-economic aspects of fruit exploitation of these two species. Socio-economic surveys were conducted in four big villages in two main agroecological zones. Fruit exploitation of these two species affected 3044 people, with estimated 39 tonnes of Z. mauritiana and 27 tonnes of B. aegyptiaca fruit collected in 2017. The surveys revealed that the main actors were women (62.05%), constituting the primary core of the actors of the value chain. Exploitation was mainly conducted in forests (68.6%) or on farms (15.4%) with no restrictions to access. Marketing of Z. mauritiana concerned fresh fruit (68.8%) and fruit processed into biscuits (82.14%), and that of B. aegyptiaca involved fruit (38.5%) and oil extracted from seeds (38.7%); the net margin was estimated at 71.71% ± 21.59% for the first species and 50.31% ± 47.99% for the second. The income was mainly used for the needs of farmers’ households. Links have been identified where consumers and processors supply seeds, after extracting the fruit pulp, to nurserymen for the production of plants for the villages or farms. This study reveals an important potential and opportunity for job creation and improved food and nutritional status of the vulnerable strata of rural communities in Niger. Improving the links between the various actors will establish a more sustainable promotion of the fruits of these two species.