Asian Journal of Research in Agriculture and Forestry
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Population Structure of Prunus africana (Hook. f.) Kalkm. and Olea europaea L. in South Nandi Afromontane Forest, Kenya
No full textPrunus africana (African cherry) and Olea eurpaea (Olive) tree species from the moist highlands of sub-Saharan Africa are subjected to industrial-scale harvesting, and therefore endangered due to their medicinal values and fine wood. Studying their population dynamics plays an important role in identifying the conservation needs in tropical ecosystems. This paper focuses on an ecological study carried out from April-June 2017, within the South Nandi Afromontane Forest, Kenya. The objectives were to analyse population density, diameter size class distribution, and the horizontal structure of Prunus africana and Olea europaea species as indicators of their respective species stability within the forest. Two-line transects established 250 meters apart were used to lay twenty systematic sample plots of 50 m x 20 m each, along with a transect at an interval of 200 m. These sample plots were further divided into five sub-sample units of 20 m × 10 m, where the number of trees with Diameter at Breast Height (DBH) >10 cm, poles 5-10 cm, saplings 1-5 cm were assessed, while the number of seedlings with DBH < 1 cm were assessed in 50 m × 1m bands within the sample plots. Two and one-way Analysis of Variance ANOVA were applied at a 5% level of significance. The population densities ranged from 860-885 stems/hectare for P.africana and 569-601 stems/hectare for O. europaea, and were significantly different (p<0.05) along the transects and between the sampled cluster sites of Chebilat, Kobujoi, Chepkongony, and Kamarich, within the South Nandi Forest. Diameter size class distribution took the shape of reverse ‘J’ curve, which characterises stable populations that naturally replace themselves through regeneration. However, in comparison with United Nation Organisation 1994 model for structurally stable East African natural forest ecosystems, the species were unstocked, which indicates low recruitment from seedlings into mature trees due to possible anthropogenic disturbances. Recruitment of both species occurred more intensively in canopy gaps but displayed inhibition near mature conspecifics throughout the forest floor. There is a need to consider population densities, regeneration, and recruitment levels in planning to restore the two species through artificial regeneration, in addition to advocate for strategic in-situ conservation interventions to enhance recruitment in South Nandi Forest. 
Effect of Land Uses and Physical Soil and Water Conservation Practices on Runoff and Soil Loss in Western Tigray, Ethiopia
No full textA field experiment was conducted in three consecutive years (2014- 2016) in the western zone of Tigray, Northern Ethiopia. It was conducted with the objectives of estimating the runoff and soil loss of four different land uses. Area closure, grazing land, treated cultivated land and the untreated cultivated land was selected in a watershed. A total of 12 runoff plots with a size of 15 m X 3 m were constructed in each land use type with the same slope (8.5%). About 25 cm height corrugated iron was constructed for each plot. A runoff collection ditch with dimensions of 2 m length, 1.2 m width and 1 m depth was dug and lined with a thick plastic sheet at the bottom side of each runoff plots to collect runoff discharge and sediment yield. After each rainfall event runoff volume in the ditch was measured and subsequently, the one-liter sample was taken to laboratory from each runoff collection ditch after the runoff is mixed vigorously. Samples filtered using filter paper and oven dried at 105 oC for 24 hours for sediment concentration calculation. The highest average surface runoff 7277 m3/ha/year and the corresponding soil loss 110 t/ha/year were recorded in the grazing land. The lowest runoff 597 m3/ha/year and lowest soil loss 2 t/ha/year were also recorded in the area closure. Hence, the actual runoff and soil losses recorded were higher in untreated cultivated land and grazing land than area closure and treated cultivated land which warrants the requirement of more effective soil and water conservation measures. Therefore, area closure is the best technology for soil and water conservation and rehabilitation of degraded land. The treated cultivated land is also the best technology on cultivated land to conserve soil and water
Land Use Effect on Surface Runoff and Soil Loss: Results of Plot-based Experiment along East-west Gradient in Subtropical China
No full textSurface runoff and soil loss were monitored in six land use types: secondary broadleaved mixed forest (BL), coniferous plantation (CF), extensively managed bamboo plantation (EB), intensively managed bamboo plantation(IB), economic forest(EF) and farmland (FL) in the east (Fuyang, Zhejiang Province), central (Pingjiang, Hunan Province) and west (Muchuan, Sichuan Province) of China. The results showed that (1) there were significant differences of surface runoff among the land use types. The surface runoff and runoff coefficient of FL ranked highest, followed by EB, then CF, IB and EF, with BL as the lowest. The surface runoff and runoff coefficient of FL was about 2-7 times of that of BL. (2) the effects were similar of land use type on the soil loss: the BL had the lowest soil loss, followed by CF, EB, IB and the highest in FL. (3) The characteristics of soil erosion for different land use types were significantly different along the gradient from east to west. The surface runoff coefficient and soil loss on the eastern China was significantly lower than that on the west, which may be attributed to the different natural conditions, social and economical development stage and the resources investment into soil and water conservation
SWOT Analysis of Large Cardamom in Ilam District, Nepal
No full textLarge Cardamom is high value and low volume crops with highest export potential in Ilam as well as in Nepal. The district was selected purposively for the analysis of internal and external factors of production. The primary data were collected during February-July 2017. The strength as main internal factors of this crop were its high price and higher profit, high demand in international market, traditional knowledge and experience, less capital investment requirement for its cultivation, and generating rural women employments. However, the other internal factor as its weakness also was comprised of high price fluctuation, lack of improved knowledge on orchard management, lack of price information to farmers, low yield due to very old orchard and no certified variety as per the altitude domains. The analysis of external factors i.e. the opportunities of the crop were the establishment of essential oil extraction industry, development of variety according to the altitude, production and distribution of disease free saplings, conduction of research and development/training, and potentiality of land area expansion for cultivation. Similarly, the other external factor or threat of the crop included the declining productivity due to diseases, price fluctuation, lack of technical manpower, drying of irrigation water resources, and propagation from mother rhizomes. The crop was found very popular due to its better strengths and opportunities. Hence, government should be given special emphasis to overcome its weaknesses and threats through research and development program
The Prediction of Leaf Biomass Production from Faidherbia albida in Semi Arid Land, Pokot County, Kenya
No full textFaidherbia albida tree is important in feeding the livestock during dry seasons when livestock feed is scarce among the people in the semi-arid regions. Despite this unique value of the tree, no models have been developed for estimating its local leaf biomass production, thus hampering its resource assessment and management planning. Hence this study was conducted to determine allometric relationships between leaf biomass production from F. albida tree and its diameter at breast height, tree height and crown diameter. Between January and March 2016, random sample of 20 trees were partially harvested in Chepareria Division. Diameter at breast height, crown diameter and total tree height were measured in the field. Sample weights of the leaves were determined then extrapolated to the whole tree production and used as a basis for developing leaf biomass models. Correlation regression analysis as provided in R-software was used to establish the relationship between F. albida leaf biomass production and the measurable tree parameters. Nine models were fitted in the study and their suitability in predicting leaf biomass established. Comparison of different models was based on: adjusted coefficient of determination (adj. R2); significance of parameter estimates when tested at the 5% probability level; homogeneity of residual variance and distribution of the residuals; Standard Error of the Estimates (SEE). Among tested models, the study suggested with adjusted R2 = 0.82 for local use. 
Influence of Different Water Frequency on the Growth and Yield of Cymbopogon schoenanthus (Camel Grass)
No full textCymbopogon schoenanthus is a biennial or perennial grass that grows in a dried stony environment, capable of withstanding harsh environmental condition. In this research, the influence of different water frequency on the yield of Cymbopogon schoenanthus was assessed. Plant sample was watered after three days, two days and one-day continuing for an interval of 12 months, But the controlled sample was watered daily. The growth of the grass was evaluated each week, up to the period when the plants were expected to reach vegetative and reproductive phase. The growth parameters estimated are plant height (cm), number of leaves per plant, number of seeds, flowers and stem or shoots bearing flowers. The result shows that samples were irrigated daily and yielded more followed by samples irrigated after one day or two days intervals. The yield and productivity of the grass samples examined was higher under conducive environmental condition. The seeds and inflorescent were obtained after four methods of cultivation in the samples which were watered daily. The seeds and flowers were dispersed by wind as the plant produced new seeds. This resulted in decrease in the number of seeds in some of the treatment, leading to less number of seeds in some of the treatments. From the research it shows that the water frequency has the effect on the growth of plant species
Breaking Secondary Dormancy in Sesbania (Sesbania sesban) Seeds
No full textAims: To investigate the efficacy of various dormancy breaking methods on Sesbania seeds.
Study Design: Complete Randomized Design with 5 treatments and 4 replicates of 100 seeds each for the treatments.
Place and Duration of Study: Department of Seed, Crop and Horticultural Science and duration of the study was 2 months.
Methodology: Sesbania seeds were subjected to the following methods; mechanical scarification, soaking in hot water (67°C) for 15 minutes, soaking in concentrated H2SO4 for 15 seconds and leaching. A control experiment where the seeds were not subjected to any treatment was also prepared. The seeds were then set up in Petri dishes up lined with 3 moist filter papers substratum for each method. The Petri dishes were then put in a growth chamber set at a temperature of 24°C and 70% relative humidity. Seeds that germinated every day were noted.
Results: Dormancy breaking methods differed significantly from the control regarding the number of seeds that germinated at P≤0.05. Leaching method (77.8%) hot water (69.5%) Mechanical scarification (62.3%) and acid scarification (64.5%) were higher than for the control (51%).
Conclusion: Leaching was shown to be the best method to alleviate dormancy in the Sesbania seeds. Soaking in hot water, mechanical and acid scarifications also significantly increase germination
Growth Response of Sunflower to Potassium Sulphate Application in Saline-sodic Soil
No full textAims: To evaluate the effect of SO42- and K+ application on growth of sunflower hybrids besides on growth parameters in a saline sodic soil.
Study Design: Laid out the experiment in Complete Randomized Design in triplicates, applying potassium sulphate in saline- sodic soil for the growth of sunflower.
Place and Duration of Study: The study was conducted in Soil Salinity and Bio-saline Research green house of Land Resources Research Institute at National Agricultural Research Centre, Islamabad, Pakistan during the period from January to March, 2018.
Methodology: Applied potassium sulphate @ 50 mg kg-1 in saline- sodic soil (ECe = 6.5dS m-1, pH = 7.7, SAR = 17) for the growth of sunflower hybrids viz. SMH-9706 and PARSUN-3.
Results: Sunflower responded significantly (P = 0.01) for growth and chemical parameters. Fresh and dry mass of PARSUN-3 were higher 14 and 12 percent respectively than that of SMH-9706. Sulphur and potassium ions uptakes were higher 32 and 22 percent respectively in PARSUN-3 than SMH-9706. Sulphur and potassium decreased Na+/K+ ratio in both the hybrids.
However, this decline was higher in PARSUN-3 than SMH-9706.
Conclusion: This study identified the way to evaluate promising genotypes of sunflower for growth and production with sulphur and potassium nutrition under saline sodic soil. 
Effect of Socio-economic Activities on Tree Species and Conservation Trend in Eco-zones of Taraba State, Nigeria
No full textThis study was carried out with the aim to assess the effect of socio-economic activities on tree species and conservation trend Ecological zones of Taraba State, Nigeria. Stratified and simple random sampling designs were used to distribute 270 copies of structured questionnaire to the people. The data were analyzed using descriptive statistics. The results showed that 64% of respondents were not participating in conservation of tree species due to poor infrastructural facilities and poverty in the study area. The majority of the people were involved in various forms of deforestation (farming 46%, fuel wood gathering 22% and settlement 9%). These practices had greatly affected tree species diversity and abundance in the study area; thereby increasing environmental problems such as flooding and soil erosion (16%). Most of the economic tree species (19) were decreasing in availability with Rauvolfia mitoria and Sterculia setigera endangered. The major factor responsible for tree species decline was anthropogenic activities (67%). Majority of the people were willing to support trees conservation. Thus, there is the need for further research to update the current list of conserved species on national red list species data bases. Also, Government stakeholders should provide more awareness on environmental education and alternative domestic energy in order to minimize indiscriminate felling of trees and over exploitation to prevent extinction of these economic tree species in the study area
Tree Species Diversity and Structure of Eda Forest Reserve, Ekiti State, Nigeria
No full textTropical rainforest is continuously threatened by timber exploitation and conversion to other land uses. In this study, tree species diversity and forest structure of Eda Forest Reserve in Ekiti State, Nigeria, were assessed using systematic line transect and purposive sampling techniques for plot demarcation and data collection. Two transects (2000m long) were laid in secondary forest and encroached farmland in the reserve, while the primary forest fragments were sampled purposively. Twenty sample plots (20m×20m) were laid out on each of the vegetation types. All trees >10cm diameter at breast height (dbh) were identified to species level and enumerated for total height and dbh. Data were analyzed using descriptive statistics such as tables, charts, frequency, percentages and diversity index analysis using paleontological statistics software (PAST 2.14). There were 60 species from 22 families, with Sterculiaceae, Caesalpiniaceae and Moraceae being the most abundant families. Individual tree populations were 380 trees/ha, 280 trees/ha and 137 trees/ha in the primary forest, secondary forest and encroached farmland, respectively. Species composition comprised 39, 38 and 19 species in primary forest, secondary forest and encroached farmland, respectively. Khaya ivorensis had the highest relative density in the three vegetation types (19.74%, 24.53% and 27.74%) respectively, while Ceiba pentandra had the highest height (53.87m). The mean basal area ranged from 0.36m2/ha (encroach farmland) to 3.18m2/ha (primary forest). Shannon-Wiener Indices were 3.22, 3.14 and 2.51 for the primary forest, secondary forest and encroached farmland, respectively. Eda forest reserve is a heterogeneous ecosystem that had variations in tree population due to anthropogenic activities. The secondary forest and encroached farmland have great potential for recovery if conservation efforts are put in place