Evaluation of Kraft pulp yield and syringyl/guaiacyl ratio from standing trees (Eucalyptus camaldulensis, E. urophylla, Leucaena leucocephala and Casuarina junghuhniana) using portable near infrared spectroscopy

Measurement of pulpwood traits from a standing tree has considerable advantage when screening large populations for tree selection. It reduces time and also eliminates requirements of transport, powdering, and storing the sample. This study describes estimation of Kraft pulp yield (KPY) in Eucalyptus camaldulensis, E. urophylla, Leucaena leucocephala, and Casuarina junghuhniana by portable NIR spectroscopy of standing trees. Calibration models were developed for KPY estimation using portable NIR spectroscopy for the four species, along with a calibration model for syringyl/guaiacyl (S/G) ratio in E. camaldulensis. The calibration models for KPY showed R2 values ranging from 0.93 ( E. camaldulensis) to 0.83 ( L. leucocephala), and 0.95 for S/G ratio. The developed calibration models for E. camaldulensis and L. leucocephala were compared with laboratory NIR models, and a variation of <±2.0% was found between both methods. The models were validated by both external and cross validation which showed <2.0% RMSEP (root mean square error of prediction) and <2.0% RMECV (root mean square error of cross validation) in external and cross validations, respectively.

Valorization of waste bark for biorefineries: chemical characterization of Eucalyptus camaldulensis inner and outer barks

Bark wastes today are viewed as a high-value resource for biorefinery due to their chemical richness and diversity. This work presents a comprehensive chemical characterization of the inner bark and the outer bark of Eucalyptus camaldulensis cultivated in Algeria. The extractives were first isolated with an Accelerated Solvent Extractor (ASE) and then analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). The content of pre-extracted bark in cellulosic polysaccharide and free sugar monomers was determined by Gas Chromatography (GC). The hemicellulose composition and amount was determined after the acid methanolysis and GC. The amount of lignin was determined gravimetrically by the Klason lignin method and the acid soluble lignin was determined by the UV method. Formic and acetic acids in the bark were determined by HPLC after alkaline hydrolysis. It was found that the extractives content were similar in the outer bark (0.85%) and the inner bark (0.88%). The cellulose content was higher in the outer bark (33.4%) than in the inner bark (28.7%). Lignin and the total hemicellulose contents were more abundant in the outer bark (31.7, 26.2%) than in the inner bark (28.6, 19.3%) whereas, sugar monomers were more abundant in the inner bark (4.4%) than in the outer bark (3.8%). The variation in acetic and formic acids and ash contents between the outer bark (1.5, 0.006 and 2.5%) and the inner bark (1.3, 0.005 and 2.4%) was small. The obtained results showed that the bark can be considered a suitable feedstock for lignocellulosic biorefinery and also for the extraction of bioactive compounds that can be used in different sectors.

Repellent and Toxicant Effects of Eight Essential Oils against the Red Flour Beetle, Tribolium castaneum Herbst (Coleoptera: Tenebrionidae)

This study was conducted to compare the repellent effect and contact toxicity of eight essential oils (EOs), including Syzygium aromaticum, Allium sativum, Eucalyptus camaldulensis, Lavandula officinalis, Simmondsia chinensis, Matricaria chamomilla, Citrus limon, and Prunus dulcis, against adults of Tribolium castaneum Herbst. Four concentrations (1, 5, 10, and 15% in acetone solvent) of each EO were tested. The 5, 10, and 15% concentrations of S. aromaticum EO had a high repellency effect against T. castaneum compared with A. sativum, E. camaldulensis, L. officinalis, S. chinensis, M. chamomilla, C. limon, and P. dulcis after 30 min of exposure. The repellency test of the S. aromaticum, E. camaldulensis, L. officinalis, M. chamomilla, C. limon, and P. dulcis EOs on T. castaneum has shown that the mortality percentages enhanced with the increase in the EOs concentration and also with the exposure time. The 15% concentration of P. dulcis and M. chamomilla EOs have a significant impact on the mortality rate of T. castaneum compared with S. aromaticum, A. sativum, E. camaldulensis, L. officinalis, and S. chinensis after the 24 h of contact test. Moreover, the 15% concentration of the C. limon EO caused a greater mortality percentage compared with S. aromaticum, A. sativum, E. camaldulensis, and L. officinalis. It could be concluded that using the S. aromaticum EO as a repellent oil and using P. dulcis, M. chamomilla, and C. limon for contact toxicity to treat the flour infested by T. castaneum can play an important role in protecting stored grains and their products.

Monitoring of Afforestation Activities Using Landsat-8 Temporal Images, Billion Trees Afforestation Project, Pakistan

In context of Bonn Challenge commitment, Pakistan (Khyber Pukhtunkhwa) has implemented forest restoration and afforestation on 0.35 million hectares between 2015–2017. Billion Tree Afforestation Project (BTAP) is an initiative of mass afforestation and forest restoration to meet the Bonn Challenge commitment. The current study is a pilot study to evaluate the success of plantation activities by assessment of regeneration, growth performance and survival rate of plantations raised under BTAP in Malakand Forest Division. Further, four vegetation indices were computed from Landsat-8 image, which include Normalized Difference Vegetation Index (NDVI), Soil Adjusted Vegetation Index (SAVI), Modified Soil Adjusted Vegetation Index (MSAVI) and Difference Vegetation Index (DVI). A total of 72 sample plots of 0.1 ha were laid out in 11 plantation sites extended over an area of 647 ha in Timargara, Chakdara and Jandool. According to the results, all the selected plantation sites showed good performance in terms of survival rate, mostly above 90%. In terms of species composition, Eucalyptus camaldulensis has the highest share (81%) followed by Robinia pseduacacia with 17% and Pinus roxburghii with 2% share in the plantation. Growth performance was good in all species; Pinus roxburghii attained an average girth of 14.3 cm and height of 3.21 feet, whereas Eucalyptus camaldulensis and Robinia pseudoacacia attained a mean girth of 10.3 and 12.1 cm with the height of 8.6 and 8.2 feet in 27 months, respectively. Further, a good correlation was observed between the volume (m3) and Landsat-8 spectral values. The highest performance (R2=0.63) was recorded by NDVI and SAVI. The temporal changes in spectral values of Landsat-8 images from 2013 to 2018 showed that the plantation was successful at these sites. The study concluded that FLR activities across the Khyber Pukhtunkwa province will rehabilitate and improve the existing forest ecosystems and support local livelihood for climate change mitigation.

Ecophysiological response of Eucalyptus camaldulensis to dust and lead pollution

Background: Air and soil pollution are among the main concerns in urban areas worldwide, and dust and heavy metals are major contributors to environmental pollution. Lead (Pb) is a highly toxic heavy metal that badly affects human health as well as plant's survival and growth. Vegetation can play an important role in ameliorating the effects of these pollutants. Eucalyptus camaldulensis is well adapted and cultivated throughout a wide range of urban environments from temperate to tropical climates. Methods: A 90 days experiment was conducted to investigate the effects of lead (Pb) and dust pollution on the growth performance of young E. camaldulensis plants. Four months old seedlings were treated with a factorial combinations of Pb (0,10 and 20 mg/l applied in irrigation) and dust levels (0,5 and 10 g applied on foliage). Results: All morphological traits (root length, shoot length, stem diameter) and biomass (root and shoot, fresh and dry mass) of E. camaldulensis were significantly reduced when exposed to higher Pb and dust levels. The highest Pb treatments exhibited greater Pb accumulation in plant roots (23.54 ± 1.61 mg/kg), shoots (15.53 ± 1.98 mg/kg), and leaves (13.89 ± 1.49 mg/kg). Dust load on leaves was greater (72.78 ± 8.1 mg/cm2) for those treatments with higher dust and Pb additions compared to the control (16.11 ± 2.0 mg/cm2). Chlorophyll content was greater at the start of the experiment (68.78 ± 0.74 mg.g-1FW) and progressively decreased over time consistently with the increase of Pb and dust levels applied. Conclusions: The results of the experiment, suggest that E. camaldulensis could be successfully grown in minimum to moderate Pb and dust polluted urban environments.

A Modified Lysimeter Study for Phyto-Treatment of Moderately Saline Wastewater Using Plant-Derived Filter Bedding Materials

The present study focuses on determining the phyto-treatment efficiency for treatment of moderately saline wastewater using organic raw materials, such as rice husk, coconut husk, rice straw, and charcoal. The moderately saline wastewater with total dissolved solids (TDS) concentration up to 6143.33 ± 5.77 mg/L was applied to the lysimeters at the rate of 200 m3 ha–1 day–1 in five different lysimeter treatments planted with Eucalyptus camaldulensis (T1, T2, T3, T4, and T5). T1 was a control without any filter bedding material, whereas rice straw, rice husk, coconut husk, and charcoal were used as filter bedding materials in the T2, T3, T4, and T5 treatment systems, respectively. Each treatment showed significant treatment efficiency wherein T3 had the highest removal efficiency of 76.21% followed by T4 (67.57%), T5 (65.18%), T2 (46.46%), and T1 (45.5%). T3 and T4 also showed higher salt accumulation, such as sodium (Na) and potassium (K). Further, the pollution load in terms of TDS and chemical and biological oxygen demand significantly reduced from leachate in the T3 and T4 treatments in comparison with other treatments. Parameters of the soil, such as electrical conductivity, exchangeable sodium percentage, and cation exchange capacity did not show values corresponding to high salinity or sodic soils, and therefore, no adverse impact on soil was observed in the present study. Also, Eucalyptus camaldulensis plant species showed good response to wastewater treatment in terms of growth parameters, such as root/shoot weight and nitrogen, phosphorus, and potassium (NPK) uptake, plant height, biomass, and chlorophyll content. Root and shoot dry weight were in the order T3 (51.2 and 44.6 g)&gt;T4 (49.3 and 43.5 g) &gt; T5 (47.6 and 40.5 g) &gt; T2 (46.9 and 38.2 g) &gt; T1 (45.6 and 37.1 g). Likewise, the total chlorophyll content was highest in T3 (12.6 μg/g) followed by T4 (12.3 μg/g), T5 (11.9 μg/g), T2 (11.5 μg/g), and the control, that is, T1 (11.0 μg/g). However, the most promising results were obtained for T3 and T4 treatments in comparison with the control (T1), which implies that, among all organic raw materials, coconut and rice husks showed the highest potential for salt accumulation and thereby wastewater treatment. Conclusively, the findings of the study suggest that organic raw material–based amendments are useful in managing the high salts levels in both plants and leachates.

Resource Partitioning in the Sunbird Species Found in Federal College of Forestry, Jos, Plateau State

Competition occurs when individuals or different species are vying for the same resource which is in limited supply. Two complete competitors cannot coexist indefinitely, therefore competitors must differ to some degree in their resource use. The research was carried to investigate how resources are partitioned among the species of sunbirds found in Federal College of Forestry, Jos. Opportunistic sightings along a 200m transect was used for observation. Sunbirds were observed using binoculars between 6:30 – 8am and by 4:30 – 6pm. Six transects were purposively selected in the study area. Sightings along a 200m transect was used to observe; species of sunbird, sex of individual sunbird species, species of flowering plant visited by the sunbird species, activity or behaviour performed by the sunbird (probing, insect hunting, roosting, perching etc.) and duration of activity. Descriptive statistics, ANOVA and post hoc test was used to analyse the data obtained. Results showed that forty-three (43) plant species were utilised by the four (4) sunbird species found in the study site with Corymbia torelliana and Hamelia patens having the highest number of visit. These four sunbird species observed were; Scarlet-chested sunbird, Variable sunbird, Green-headed sunbird and the Copper sunbird. Mean number of plants visited shows that Green-headed sunbird visited more plants than the other three species (28.89) which was highly significant (p=0.001). Copper sunbird spent the highest foraging time (67.71) which showed no variation with the other species (p=0.516). Females of the sunbird species visit more plants species and spent more time foraging as compared to the males although there was no variation (p= 0.984 and p= 0.906 respectively). The activities of the males (perching, hovering, probing, feeding) was higher than that of females and had a high level of significance (p=0.001). Callistemon citrinus, Corymbia torelliana, Eucalyptus camaldulensis, Hamelia patens, Parkia biglobosa and Ziziphus mucronata were utilised by all the sunbird species. Scarlet-chested sunbirds spent more time probing which aids pollination of plants in the study site and hence ecologically important to the plants found in the study site.