We investigated the effect of fire on understory plant species density in University of Port Harcourt Biodiversity Centre four months after fire incident. This is aimed at the knowing the ability of the forest to recover from bush fire. Twenty four (4 m x 4 m) plots (14 burnt and 10 un-burnt or control) were mapped out. The plant seedlings in these plots were sampled, identified and enumerated. The diversity, relative abundance, relative frequency, relative diversity, species importance value, family importance value and seedling density were determined. A total of 53 plant species belonging to 35 families were identified in the area studied. The un-burnt (control) plots had 11 species with 9 plant families while the burnt (impacted) plots had 52 species and 33 families. Fabaceae and Rubiaceae families had the maximum number of species in the control plots, while Asteraceae, Poaceae and Fabaceae families had the maximum number of species in the burnt plots. Based on the habit of the plant species identified, there is difference in the number of plant species, seedling density, relative abundance, species density and importance values (dominance) between the burnt and the control plots. In the burnt plots lianas, grasses, herbs, shrubs and trees had 8, 7, 21, 9 and 7 species respectively while in the control plots we recorded 2, 0, 2, 3 and 4 for lianas, grasses, herbs, shrubs and trees respectively but the relative abundance of lianas and trees in the control plots were less than that of burnt plots. Seedling density in the burnt plots varied from 57 to 9091 seedling ha-1; Alchornea cordifolia had the highest relative frequency of 9.63%. In the unburnt (control) plots relative frequencies of the species were relatively higher than the burnt plots. Baphia nitida (16.67%) had the maximum relative frequency while Picralima nitida, Elaeis guineensis, Spigelia anthelmia and Cissus rependa had the least values of 5.56% each. The relative diversity of the different families of plant seedlings in the study area varied from 0.0 to 9.67 in burnt plots and 6.33 to 14.26 for control plots. In the burnt plots, FIV varied from 0.81 to 21.05 while it ranged from 12.05 to 13.41 in the control plots. Euphorbiaceae (11.38%) had the highest relative frequency in the burnt plots. Fabaceae (17.14%) which was the second largest in the burnt plots was [C1] had the maximum relative frequency in the control plots while Araceae, Poaceae and Apocyanaceae (5.71% each) had the least values. The seedling density in burnt plots varied from Poaceae (15987 ha-1) to Onagraceae and Smilaceae (66 ha-1 each). In the control plots the family densities are as follows: Rubiaceae (8542 ha-1); Poaceae and Apocyanaceae (1042 ha-1 each). This showed that fire stimulates the germination of certain seeds and promote the growth of certain plants in secondary succession and that the Centre has high potential of recovering from the fire incident however, we recommend that the forest be protected from any sort of fire to conserve and preserved the biodiversity of this Center. It is therefore important to conduct further study in order to monitor the impact of other environmental factors on the recovery of the burnt flora.
The orchid species, Neottia cordata and Goodyera repens found in large parts of Europe and North America, but rarely found in the Netherlands. Hence, the Forestry Services of Netherlands is working to preserve these endangered orchid species by maintaining the current forest structure and applying different forest management strategies. The aim of the study were, (1) to identify an environmental factors which determine the occurrence of the orchid species, mainly G. repens and N. cordata, (2) to recommend management options to preserve identified suitable environmental factors in a mixed forest and forest structure. The study was conducted in Hoornsebos. In each sample plot, we recorded the vegetation composition, forest structure and composition, humus and litter layer, and canopy openness. In the study forest, we found two plant communities (i,e, Vaccinio-Piceetalia and Quercetalia-roboris). Both N. cordata and G. repens were abundant in Vaccinio-Piceetalia plant community, but were rare in the Quercetalia-roboris plant community. Our results showed that both orchids’ species are dependent on the occurrence of needle litter and need to grow in low productive environment, where they are not outcompeted by other plants. There is also a general trend of development towards more broadleaved tree composition which has a negative effect on the occurrence of both orchid species. The development of a shrub layer leads to increased shading and canopy closure and likely to decrease the abundance of N. cordata in the study forest. Aging of coniferous forests will lead to further build-up of the litter layer which negatively affects G. repens. Without good forest management, the existing suitable environmental conditions for both G. repens and N. cordata, will likely to degrade, hence active management is required for sustainable conservation of these orchid species.
Aims: To determine the effect of protein supplementation to Ankole x Friesian crossbred calves grazing natural pastures on their growth performance, and the economic viability of supplementation.
Study Design: Randomized Complete Block Design.
Place and Duration of Study: Kiruhura district in Uganda; September to December 2012.
Methodology: Nine weaned crossbred calves aged 5-6 months on each of the five experimental farms were divided into three groups. Each group was randomly assigned one of the three dietary treatments comprising: a control where calves depended solely on pastures, supplementation with homemade concentrate (HMC), or lablab hay (LH). Calves were released daily at 8.00 am to graze till 3.00 pm when those on supplementation were returned to their pens for supplementary feeding; meanwhile the control group was left grazing until evening. Body weight (BW) and body condition (BC) of each calf were recorded at three weeks’ intervals. Financial efficiency of supplementation was estimated using the ratio of total revenue (TR) to total variable cost (TVC).
Results: The mean total DMI (kg/day) of calves supplemented with HMC (3.28) and LH (2.94) were higher (P < .001) than that of calves on sole grazing (1.90). The mean daily BW gain (g/day) of calves supplemented with HMC (540) was higher (P = .03) than that of calves supplemented with LH (423) and those on sole grazing (357). The BC scores of calves fed HMC and LH were 4.74 and 4.90 respectively, and were higher (P = .04) than that of calves (4.32) on sole grazing. Returns per unit variable cost of production measured by TR/TVC for calves on sole grazing were 1.30 compared to 1.11 and 0.92 for calves fed LH and HMC, respectively.
Conclusion: Supplementing crossbred calves grazing natural pastures with HMC improves their growth performance, but might be uneconomical in the short run due to cost of ingredients.
Scarcity of fodder is the major limiting factor for increasing livestock production in Kenya. With rising energy costs and declining water levels in the semi-arid tropics and sub-tropics, crops that use less water like finger millet could become an alternate fodder crop. The fodder potential of three finger millet varieties (U-15, P-224 and a local check) were evaluated under four P fertilizer levels (0, 12.5, 25 and 37.5 kg ha-1 P2O5) at three sites in Kenya for two cropping seasons. The trials were laid in randomized complete block design in factorial arrangement and replicated three times. A maximum of 28,189 kg ha-1 fresh stover yield was realized in the 25 kg ha-1 P2O5 treatment and consequently 11,616 kg ha-1 dry stover yield. The 25 kg ha-1 rate elicited the highest fresh stover yield at Kakamega and Alupe for both seasons while at Kiboko a linear increase was observed on the stover yield with increasing rates where the highest rate had more than 15% yield compared to the control. The varieties also showed significant differences in all the sites with the local variety, Ikhulule, showing the highest fresh and dry stover yield at Kakamega and Alupe peaking at 28,852 and 12,826 kg ha-1 fresh and dry stover yields respectively. Interactions between variety and phosphorus rates were revealed on the crude protein content of the finger millet stover. At Kiboko, the highest crude protein (11.0%) on varieties P-224 and U-15 was exhibited at the highest rate while on the local variety, Ekalakala, the highest protein (10.9%) was realized at the 25 kg ha-1 P2O5. At Kakamega and Alupe, the highest protein was observed on the local variety, Ikhulule at 12.5 kg ha-1 P2O5 rate with variety P-224 and U-15 showing the highest at the 25 and 37.5 kg ha-1 P2O5 respectively. Therefore, finger millet can provide a unique opportunity to improve the availability of fodder to smallholder livestock farmers.
How plant species are distributed in a given ecosystem is important for ecologists and conservationists because tropical forests are very diverse. This makes the question of what determines species commonness and rarity more interesting. This paper aims to assess the environmental range, frequency and density of three plant functional groups (Pioneer, non-pioneer light demanding and shade tolerant) in Ghanaian tropical forests. We established a 1-ha plot in which trees were inventoried in a nested design, providing a total number of 2205 plots. All living trees ≥ 30 cm diameter at breast height (DBH) were sampled in 1ha plot, trees 10–30 cm DBH in 0.1-ha subplots and trees 5–10 cm DBH in 0.05-ha subplots. Then, the following variables were recorded and calculated; frequency (the number of plots in which the species is present) and the average density (the average number of trees per plot, for the plot in which the species is present), and environmental range (rain fall range and soil fertility) of each species. We used a Kruskal-Wallis, Chi-square and multiple regression analysis to evaluate each research question. The results showed that non-pioneer light demanding tree species have wider environmental range and higher frequency than pioneer and shade tolerant tree species. This might be due to non-pioneer light demanding tree species share the characteristics of pioneer and shade tolerant species. Moreover, higher percentages (55%) of non-pioneer light demanding species are commonly found based on the threshold values of three components of rarity (Association among environmental range, frequency and density). In addition, 63% of tree species were rare in seven forms of rarity, and 37% of tree species were commonly found in Ghanaian forest. In conclusion, non-pioneer light demanding tree species have higher frequency and wider environmental range, whereas, shade tolerant tree species have higher density. Overall, environmental factors have effect on the frequency and density of woody species.