Cupressus Lusitanica Research Articles

Changes in Physical and Water Sorption Characteristics of Three Solid Woods after One-Sided Surface Charring.

One-sided surface charring of wood is a modification process used to lower moisture absorption and improve the resistance to biological degradation for durable surface exterior claddings. Cupressus lusitanica, Gmelina arborea, and Tectona grandis wood samples from fast-growth plantation were charred with a hot plate using three temperatures (300, 350, and 400 °C ± 3 °C) for 10 min. Wood density, surface quality (color and presence of splits), and sorption characteristics (wetting rate and water uptake) were evaluated. Results show that samples charred at 300 °C presented a lower loss of density and thickness than samples charred at 400 °C. Changes in the chemical structure of the wood as a result of the high temperatures caused a decrease of all color parameters (L*, a*, and b*). These values decreased in the samples charred at 400 °C for the three species. Also, the presence of cracks and splits on the surface, or in some cases the presence of detachments from the charring surface, was mostly observed in the samples charred at 350 and 400 °C. One-sided surface charring reduced the liquid water sorption of wood samples in comparison with that of reference samples, especially for C. lusitanica and T. grandis. G. arborea, due to the composition of its anatomical structure and its initial density, chars faster than the other species, causing a greater loss of density, wetting rate values like those of the reference wood, and higher values of water uptake.

Towards Urban Forest Restoration in the City of Bukavu, Eastern Democratic Republic of Congo: Residents' Perceptions

Purpose: Demographic explosion is a common phenomenon in the Democratic Republic of Congo, especially in the city of Bukavu, where more than 1.6 million inhabitants live in 60 km², following the rural exodus due to insecurity in rural areas. This situation has led to deforestation, resulting in the destruction of most of the old green spaces, exposing the city to higher risks of flooding, erosion, landslides and loss of biodiversity, among other environmental problems. This study aims to understand the population's perception of deforestation in Bukavu, and to inform policy makers on how to restore urban forests. Methodology: To collect data for this study, we sampled and interviewed 210 informants, with 70 informants in each of the three communes of Bukavu: Kadutu, Ibanda and Bagira. Findings: The vast majority of informants are in favor of restoring green spaces (85%). At least 72.9% of them recognize that green spaces are important for air purification, environmental improvement, ornamentation, erosion control, biodiversity conservation and food production (in the case of fruit trees). They agree that the vegetation cover has decreased, especially since the 2000s, mainly due to the rural exodus and unregulated housing construction (81.9%). The population is aware that they are the main beneficiaries of green spaces (87.1% of informants) and accuse the government of being the main destroyer of green spaces and that it should be the main actor in their restoration. At the same time, residents recognize their share of responsibility for the destruction and restoration of urban green spaces, but consider it to be less than that of the government. In order to restore green spaces, they suggested tree planting initiatives (51.7%), with a preference for Eucalyptus sp., Cupressus lusitanica, ornamental and medicinal trees. Awareness raising and planned urbanization are among the strategies proposed to restore these spaces. A unique contribution to theory, practice and policy: The results of this study pave the way for a multidimensional understanding of climate adaptation, and demonstrate the need for a collective awakening of all stakeholders and the full mobilization of all actors in the quest to restore green spaces in the city of Bukavu for a healthier environment.

Long Short-Term Memory and Bidirectional Long Short-Term Memory Modeling and Prediction of Hexavalent and Total Chromium Removal Capacity Kinetics of Cupressus lusitanica Bark

Hexavalent chromium [Cr(VI)] is a high-priority environmental pollutant because of its toxicity and potential to contaminate water sources. Biosorption, using low-cost biomaterials, is an emerging technology for removing pollutants from water. In this study, Long Short-Term Memory (LSTM) and bidirectional LSTM (Bi-LSTM) neural networks were used to model and predict the kinetics of the removal capacity of Cr(VI) and total chromium [Cr(T)] using Cupressus lusitanica bark (CLB) particles. The models were developed using 34 experimental kinetics datasets under various temperature, pH, particle size, and initial Cr(VI) concentration conditions. Data preprocessing via interpolation was implemented to augment the sparse time-series data. Early stopping regularization prevented overfitting, and dropout techniques enhanced model robustness. The Bi-LSTM models demonstrated a superior performance compared to the LSTM models. The inherent complexities of the process and data limitations resulted in a heavy-tailed and left-skewed residual distribution, indicating occasional deviations in the predictions of capacities obtained under extreme conditions. K-fold cross-validation demonstrated the stability of Bi-LSTM models 38 and 43, while response surfaces and validation with unseen datasets assessed their predictive accuracy and generalization capabilities. Shapley additive explanations analysis (SHAP) identified the initial Cr(VI) concentration and time as the most influential input features for the models. This study highlights the capabilities of deep recurrent neural networks in comprehending and predicting complex pollutant removal kinetic phenomena for environmental applications.

Biodiversity and Structural Analysis of Woody Plant Species of Home Gardens in Basona Worana District, North Shoa Zone of Central Ethiopia.

The purpose of this study was to investigate the biodiversity and structure of woody plants of HGs in the Basona Worana district (BWD). For this, six kebeles and 138 HGs from three agroecologies of BWD were selected using various sampling techniques. The plot size used per HG was 400 m2. Diversity and important value indices (IVIs) were computed. For their structural analysis, the diameter at breast height (DBH) and height were also measured for trees and shrubs fulfilling the standards (diameters at breast height (DBH) ≥2.5 cm and height >2 m). Thus, a total of 42 woody species belonging to 37 genera and 26 families were identified. Fabaceae was the most abundant family, followed by Euphorbiaceae. Trees were the dominant habit. The richness in Kola HGs (33) was higher than Dega (14) and Woinadega (19) HGs, with an overall mean richness of 4.14 per HG of BWD. The Shannon, Simpson, and evenness indices for HGs in the district were 1.05, 0.55, and 0.75, respectively, showing their moderate diversity with even distribution. The Sorenson's similarity of HGs between Dega and Woinadega, Kola and Dega, and Kola and Woinadega were 40%, 28%, and 32%, respectively. The multiple site similarities of woody species among three ecological zones (36%) were still <50%, showing no similarity. The overall DBH and height classes' patterns of the woody species individuals abruptly decreased towards their highest classes. Similar DBH and height classes' patterns of woody species individuals were also observed in Kola and Woinadega agroecologies, indicating their selective tree cutting. The mean values of DBH, height, basal, and crown areas of the woody species in the district were ∼14 cm, ∼6 m, ∼29 m2·ha-1, and 5 m2, respectively. Based on IVI, most of the HGs were dominated by Eucalyptus globules (93.35), followed by Eucalyptus camaldulensis (45.04), Rhamnus prinoides (22.4), and Cupressus lusitanica (22.33). Hence, actions should be taken to promote the diversity and managing of HGs' woody species of BWD.

Bio-waste derived multifunctional carbon dots for white light generation, forensic and antibacterial applications

The synthesis of multi-colour emitting solid-state fluorescent (SSF) carbon dots (CDs) is a challenging task due to the phenomenon of aggregation-induced self-quenching. However, this study presents an efficacious method to synthesize CDs from the sap stain of the cupressus lusitanica tree (cl-CDs) via a simple one-step microwave treatment. The resulting SSF CDs exhibited a particle size of approximately 3 nm, high stability, and remarkable efficacy in light conversion when coated on a UV light emitting diode (UV LED). The ensuing coating generated white light with CIE colour coordinates of (0.33, 0.34) and a high luminescence efficiency of approximately 671 L/W. The fluorescence capabilities exhibited by the cl-CDs in response to 254 nm and 365 nm UV light excitation make them an ideal choice for developing fluorescent inks to prevent counterfeiting. Moreover, the study investigated the notable fluorescence properties of cl-CDs as a luminescent fingerprint powder for the recognition of latent fingerprints on various surfaces. Additionally, the antibacterial potential of cl-CDs was evaluated against gram-positive and gram-negative bacteria, where the cl-CDs were utilized as an antibacterial dusting powder for fluorescent imaging of latent fingerprints on different substrates. Therefore, we believe that our present work offers a plethora of exciting possibilities for the multifunctional application of SSF green CDs with significant implications in white light generation, counterfeiting prevention, forensic applications, and healthcare.

Influence of Thinning and Pruning Regime on Woody Species Density and Abundance

The revival of forests is gaining prominence, with a focus on common tree species. However, the most affected species by fragmentation are the exotic woody species; therefore attention to forest silvicultural practices is essential. Kenya is acknowledged as one of the nations that value its forest environment greatly, although there are still restrictions on the application of silvicultural regimes there. This is a result of the continued strong demand for wood. It is anticipated that silvicultural regimes would eclipse Kenya’s fragmentation tactics. Thus, the goal of this research was to evaluate the influence of thinning and pruning regime on the woody species density and abundance in Kimondi forest, Nandi County, Kenya. This study was centered on Eucalyptus saligna, Cupressus lusitanica and Pinus patula as the woody species that are harvested for timber in Kimondi forest. The island biogeography theory served as the basis for this research. The number of woody species per plot, the basal area per plot, the different types of woody species, the total number of each woody species in the study area, the diameter at breast height, soil type, plantation size, soil depth and forest pest were the intervening factors. The study employed a cross-sectional descriptive study design. The study area’s species types were observed, observation schedule was filled, 30 sample plots were randomly selected each measuring 20m by 20m, and the number of woody species in each plot counted and recorded as the primary data. To assess the appropriateness of the species chosen, Two-way Analysis of Variance was used. Based on the study’s findings, Effect size is 36.098%, hence 36.098% of the variation of the abundance and density of woody species can be explained by the thinning and pruning regime. There was a significant interaction. In thinning and pruning regime,Pinus patula was the most abundant with a mean and standard deviation of 6.433a ± 2.37, Cupressus lusitanica had 4.467b ± 1.74 while Eucalyptus saligna had 3.267c ± 1.74.There was a significant difference in the woody species abundance indicated by LSD = 0.711 and p-value = 0.001**.The importance of this research was to raise awareness about the application of silvicultural regimes to enhance the density and abundance of woody species in Kimondi Forest, Nandi County, Kenya, in order to mitigate the consequences of increasing forest fragmentation and species extinction

Floristic Composition, Diversity, and Regeneration of Woody Plant Species of Dabal Forest in Southeastern Ethiopia: Implication for Conservation.

Floristic composition, population structure, and regeneration status of woody species of Dabal forest found in East Hararghe zone of Oromia Regional State, Ethiopia, were studied. Vegetation data were obtained from 52 main plots of 20 × 20 m for mature woody species and 5 subplots of 5 × 5 m for seedlings and saplings. Density and dbh of each live woody plant species found in each sample plot were recorded. Frequency, basal area, importance value, and Shannon-Wiener diversity indices were also computed. Totally 59 woody plant species distributed in 33 families were documented. Of these, 45.80, 44.10, and 5.08% were shrubs, trees, and lianas, respectively. Species diversity and evenness indices were 3.56 and 0.87, respectively. Stem count of all woody species was 3379 stems ha-1. Out of this, 44.6, 30.8, and 24.59% were seedlings (dbh <3.5 cm), saplings (dbh between 3.5 and 10 cm), and mature (dbh >10 cm) individuals, respectively. Total basal area of all individuals with dbh ≥3.5 cm was 29.88 m2 ha-1. Juniperus procera, Cupressus lusitanica, Eucalyptus globulus, Afrocarpus falcatus, Eucalyptus camaldulensis, Myrsine africana, Maytenus undata, Hagenia abyssinica, Ekebergia capensis, and Cordia africana were species with top ten IVI. Most of these species were top densest, dominant, and frequent. Analysis of population structure based on pooled densities of all species in each dbh class showed that density of seedling > sapling > mature individuals, signifying healthy population structure with good natural regeneration potential. On individual basis, however, 35.6 and 8.5% of species showed fair and poor regeneration statuses, respectively, that deserve attention for conservation.

Produksi Dan Laju Dekomposisi Serasah Hutan Kampus Institut Pertanian Bogor, Kabupaten Bogor, Indonesia

Forests are important habitats that support an ecosystem consisting of various types of plants that have production potential and litter decomposition rates. This research aims to find out how to calculate the production and decomposition rate of litter in homogeneous forest and heterogeneous forest terrestrial ecosystems. The research was carried out in homogeneous and heterogeneous forest areas in the IPB University campus area, Bogor Regency, West Java Province. The sampling process seemed to be carried out using 1x1 m nylon mesh litter trap method for 5 weeks. The results of the research show that the composition of the species that grow in heterogeneous forest areas is Kisabun (Filicium decipien), Sawo kecik (Manilkara kauki), Bisbul (Diospyros blancoy), Water guava (Eugenia aduea), Matoa (Pometia pinnata), Pinus (Cupressus lusitanica), and Meranti (Shorea sp), while in the homogeneous forest ecosystem is the rubber tree (Hevea brasiliensis). The amount of waste collected in heterogeneous forest ecosystems is greater than in homogeneous forest ecosystems (Rubber forests), namely 98 grams and 5.2 grams respectively with results in heterogeneous forest ecosystems of 7.2 grams dry weight from 10 grams wet weight, whereas in homogeneous forest ecosystem (rubber forest 0.8 grams dry weight from 2 grams wet weight). The decomposition rate of litter in heterogeneous ecosystems is 0.21 grams/year, while in rubber forest ecosystems it is 0.17 grams/year.

Chromium Recovery from Chromium-Loaded Cupressus lusitanica Bark in Two-Stage Desorption Processes.

Hexavalent chromium (Cr(VI)) contamination poses serious health and environmental risks. Chromium biosorption has been employed as an effective means of eradicating Cr(VI) contamination. However, research on chromium desorption from chromium-loaded biosorbents is scarce despite its importance in facilitating industrial-scale chromium biosorption. In this study, single- and two-stage chromium desorption from chromium-loaded Cupressus lusitanica bark (CLB) was conducted. Thirty eluent solutions were evaluated first; the highest single-stage chromium desorption efficiencies were achieved when eluent solutions of 0.5 M NaOH, 0.5 M H2SO4, and 0.5 M H2C2O4 were used. Subsequently, two-stage kinetic studies of chromium desorption were performed. The results revealed that using 0.5 M NaOH solution in the first stage and 0.5 M H2C2O4 in the second stage enabled the recovery of almost all the chromium initially bound to CLB (desorption efficiency = 95.9-96.1%) within long (168 h) and short (3 h) desorption periods at each stage. This study clearly demonstrated that the oxidation state of the recovered chromium depends on the chemical nature and concentration of the eluent solution. The results suggest the possible regeneration of chromium-loaded CLB for its subsequent use in other biosorption/desorption cycles.

GC-MS analysis and the effect of topical application of essential oils of Pinus canariensis C.Sm., Cupressus lusitanica Mill. and Cupressus arizonica Greene aerial parts in Imiquimod–Induced Psoriasis in Mice

Ethnopharmacological relevanceTraditionally, Coniferous plants, in particular Pinus and Cupressus species, have been used in the treatment of burns, skin infections, and immune-mediated inflammatory diseases such as psoriasis. Aim of the studyA comparative study between essential oils (EOs) extracted from aerial parts of three coniferous plants: Pinus canariensis C.Sm. (PC), Cupressus lusitanica Mill. (CL) and Cupressus arizonica Greene (CA), cultivated in Egypt, was designed to investigate their composition and their anti-psoriasis mechanism. Materials and methodsThe phytochemical profiles were confirmed using Gas Chromatography–Mass Spectrometry (GC-MS) method. In-vivo Imiquimod (IMQ)-induced psoriasis model was performed and EOs were applied topically and compared to mometasone cream as a standard subsequently histopathological analysis and inflammatory biomarkers were measured. ResultsIn GC-MS analysis, Monoterpene hydrocarbons, sesquiterpene hydrocarbons and oxygenated monoterpenes were the major detected classes in the three plants, except in Pinus canariensis essential oil, oxygenated monoterpenes were absent. A significant attenuation of imiquimod-induced psoriasis symptoms after topical application of P. canariensis C.Sm., and C. lusitanica Mill. essential oils were observed by reducing the psoriasis area severity index (PASI) score, alleviating histopathological alteration, restoring the spleen index, and decreasing serum levels of interleukins 23 and 17A. Indeed, the results of Pinus canariensis essential oil is comparable to mometasone and showed no significant difference from standard treatment. On the other hand, the topical application of C. arizonica essential oil failed to alleviate imiquimod-induced psoriasis symptoms as observed in the PSAI score, the histopathological investigation, and the spleen index. ConclusionThe essential oils of P. canariensis C.Sm., and C. lusitanica Mill aerial parts could be promising candidates for psoriasis treatment and for further studies on inflammation-related skin diseases.

Assessment of Farmer’s Tree Preferences and Their Seasonal Frost Management Practices in Frost-Affected Highlands of Eastern Ethiopia

Deforestation, land degradation, and low survival of planted seedlings are serious problems in highland Ethiopia. To address these problems, different land management practices such as afforestation and conservation program have been implemented; however, the success to date limited due to environmental stress and insufficient post-planting care. Therefore, the objective of this study was to investigate farmer’s tree needs and their traditional knowledge of seasonal frost management practices in selected frost-affected highlands of Eastern, Ethiopia. A total of 111 households were randomly selected for interviews on farmer’s tree species preference, frost management practices, and the causes of seedling mortality in the study area. Furthermore, key informant interviews and focus group discussions were used to collect the data. Descriptive statistics were used to analyze the data. The results confirm that season frost (55.6%) followed by free grazing (22.2%), inappropriate species site match (11.1%), and inappropriate planting time (5.6%) were major causes of seedling mortality in the study area. Organic mulch, plant cover, smoking, watering, and manuring were seasonal frost management practices applied by farmer’s to enhance seedlings’ survival in the study areas. However, this indigenous knowledge should be encouraged by the government through improved research, and extension services, to enhance seedlings’ survival in the study areas as well as to introduce it in different frost-prone highlands of Ethiopia. Moreover, species such as Eucalyptus globulus’ Labill, Cupressus lusitanica Mill., Juniperus procera Hochst. ex Endl., Hagenia abyssinica a (Bruce) J.F.Gmel, and Podocarpus falcatus (Thunb.) Mirb. (syn. P. gracilior Pilg.), were suggested as frost-tolerant species in the study area. Therefore, it is recommended that planting these tree species through research and campaign is essential to reduce land degradation in the frost-affected highlands area of the country, particularly in the study area.

Estimation of the biomass and carbon in Cupressus lusitanica Mill. trees in Costa Rica

[Introduction]: Forest plantations are an important carbon sinks and reservoirs while providing other important environmental goods and services. [Objective]: In this research, we developed models to estimate the biomass and carbon content of Cupressus lusitanica Mill trees and its components or fractions, in forest plantations in Costa Rica. [Methodology]: Through the destructive sampling of 43 trees, a sample of each component was obtained to determine dry matter and carbon content. The models were built through linear regression analysis and ordinary least squares, using the normal diameter as the independent variable. Models were selected through the weighted sum of the calculated statistics and the graphical analysis of the residuals. [Results]: The coefficient of determination (R2) was greater than 83.8 % and the estimation error or bias was less than 7.2 %. The leaf and root fractions were more difficult to model, given their lower fit and higher error. The stem represents 61.7 % of total tree biomass, the branches 17.1 % and the roots 9.1 %. The aerial biomass expansion factor was 1.54 (1.3 and 1.24 for branches and foliage) and 1.12 for roots. [Conclusions]: Allometric models accurately predict biomass and carbon content, are easy to use, and become useful low-cost tools to quantify the ecologic and greenhouse gas emission mitigation functions of these forests.

Spatial comparisons of productivity and carbon sequestration for Cupressus lusitanica and macrocarpa within New Zealand

Cupressus lusitanica and C. macrocarpa are two fast growing conifer species with valuable timber that have been widely established throughout New Zealand. Despite the importance of these two species within New Zealand and in many other countries, little research has investigated how volume, height, and carbon productivity are influenced by environment. Volume growth of these two cypress spp. has been recently described using the 300 Index which quantifies the mean annual volume increment at age 30 yrs for a stand density of 300 stems ha−1. Using New Zealand growth data obtained from 290 plots, the objectives of this study were to (i) develop models and fine resolution national maps of 300 Index and site index, (ii) use these two productivity metrics and allometric equations to develop models of carbon stocks for the two species, and (iii) spatially predict carbon across New Zealand for C. lusitanica and macrocarpa grown under a factorial range of stand densities (400, 650 and 900 stems ha−1) and ages (30, 40 and 50 yrs).Plot measurements showed wide variation in 300 Index which reached 26.9 and 29.0 m3 ha−1 yr−1, respectively, for C. lusitanica and C. macrocarpa. Site index (age 30 yrs) reached values of 31.9 and 34.1 m for C. lusitanica and C. macrocarpa, respectively. Models developed for C. lusitanica had high accuracy for both 300 Index (RMSE = 2.48 m3 ha−1 yr−1; R2 = 0.75) and site index (RMSE = 1.78 m; R2 = 0.84) while models developed for C. macrocarpa had similar, but slightly lower, accuracy for 300 Index (RMSE = 2.86 m3 ha−1 yr−1; R2 = 0.72) and site index (RMSE = 1.86 m; R2 = 0.81).Spatial predictions of the two productivity metrics showed distinct differences between species with C. lusitanica being more sensitive to cold, dry, and wet conditions than C. macrocarpa. Under the mid-range scenario (age 40, 650 stems ha−1) mean carbon sequestration in above and below ground biomass, dead wood, and litter pools for C. macrocarpa was higher than C. lusitanica in both the North Island (321 vs. 296 t C ha−1) and South Island (222 vs. 120 t C ha−1). Carbon was higher for C. macrocarpa than C. lusitanica within, respectively, 62 and 94% of the North and South Islands under the mid-range scenario. Carbon markedly increased with stand density and age and gains were greatest between ages 30 and 40 and from the low to moderate stand density for both species.

Influence of pot size on early seedling growth of Grevillea robusta and Cupressus lusitanica in Kenya

Pot size is vital for raising of nursery seedlings. Different sizes of pots are needed for various tree species. An experiment was set up to investigate the best pot size for Cupressus lusitanica and Grevillea robusta species. The experiment was laid down as a RCBD with 8 treatments replicated 3 times. Treatments comprised of 4 different pot sizes as follows: large, medium, small and smallest as well as two species. Forest soil mixture was used for potting and 10 pots were used per each treatment per replicate while 7 plants were randomly selected for sampling. The experiment was carried out from September 2017 for a period of 8 months. The variables measured included; shoot, foliage and roots. ANOVA was done using Genstat package while the means were separated at P&lt; 0.001 using LSD. The results showed that large pots had significantly (P&lt;0.001) higher values in height, shoot fresh biomass, total fresh plant biomass and seedling stem volume compared with the other pot sizes. Large pots also showed significantly higher root collar diameter (6.23 mm) compared with the medium pot (4.33 mm). For species, Cypress showed significantly superior height (27.84 cm) and number of leaves (24.52) compared with Grevillea (18.73 and 18.27 cm respectively). In conclusion, shoot fresh biomass and total fresh plant biomass were positively correlated with pot size. This study recommends the use of large pots for raising Grevillea and Cypress seedlings in the nursery since they take 8 months to attain planting size.

Lumber Recovery Rate of Cupressus lusitanica in Arsi Forest Enterprise, Ethiopia

In Ethiopia, sawmills have poor capacity utilization primarily due to the outdated equipment that resulted in a low recovery rate and the production of a high amount of wastage. The lumber recovery rate is the output (lumber) of a log in the sawing process. In Ethiopia, Cupressus lusitanica is significantly used for lumber, for furniture production, construction, poles and posts. Sampled logs were processed according to the normal production rate and standard lumber dimension of the sawmill for the purpose of estimating the lumber recovery rate. The present study aimed to investigate the lumber recovery rate of C. lusitanica and the factors affecting it. A total of 26.93 m3 of lumber was produced by the sawmilling operation, representing 72.86% of the overall lumber recovery rate. Furthermore, the sawdust and slabs were recorded as 2.92 m3 (7.90%) of sawdust and 7.11 m3 (19.24%) of slabs, respectively. There were a number of factors that decreased the magnitude of the lumber recovery rate. It was observed that cutting using a wider saw kerf caused a reduction in the rate of lumber recovery owing to the generation of an increased quantity of sawdust. The lumbers were air-seasoned in the sawmill yard. Maximizing the volume of the lumber recovered from the logs can increase the sawmill profitability, lessen the effects of climate change, ensure the sustainable use of natural resources, enhance the energy efficiency and manage wood waste (e.g., recycling and prevention) for green economic development and industrial transformation. This species has a great demand in the wood industry of Ethiopia; hence, the plantation and yield of C. lusitanica must be expanded in order to provide sustainable forestry, protect valuable forest resources and safeguard the biodiversity in the country.

Growth Models for Even-Aged Stands of Hesperocyparis macrocarpa and Hesperocyparis lusitanica

The cypress species Hesperocyparis lusitanica (Mill.) Bartel and H. macrocarpa (Hartw.) Bartel (formerly known as Cupressus lusitanica and C. macrocarpa) are widely grown in New Zealand where they are noted for their high-value timber. Preliminary cypress growth models were developed in New Zealand in 2004 based on limited growth data. Here, we describe new stand-level growth models developed for these two species using measurements from 521 permanent sample plots. Each model consists of several component sub-models including a height/age model, a diameter/age model, a mortality function and a stand-level volume function, with different parameter estimates used for each species. The mean top height is predicted from age and site index using common-asymptote Richards models. Modified common-asymptote Korf functions are used to predict the mean diameter as a function of age, stand density and a diameter index. The volume-based 300 Index, defined as the mean annual volume increment at age 30 years for a reference regime of 300 stems ha−1, can be calculated directly from the site index and diameter index using the volume function. These models will be of considerable value to forest managers for regime evaluation and yield prediction. By more robustly describing site productivity using the 300 Index, the models provide an improved framework for understanding and quantifying site productivity.

Contrasting climate drivers of seasonal growth in western vs. eastern Mexican mountain conifer forests

Hydroclimate affects the radial growth responses of trees, but the drivers of their spatial and population variability are not sufficiently understood. We addressed this issue by sampling several conifer populations located at the same latitude, but at different longitude and elevation in western (W) and eastern (E) Mexican regions. We used dendroecology to disentangle how earlywood width (EW), latewood width (LW) and adjusted LW (LWadj), i.e. the residuals after removing EW influences on LW, responded to climate variables (temperature and precipitation), climate indices (Southern Oscillation Index, SOI, Niño 3.4, Pacific Decadal Oscillation, PDO) and a drought index (Standardised Precipitation-Evapotranspiration Index, SPEI). The W species (Pinus herrerae Martínez, Pinus durangensis Martínez, Abies durangensis Martínez and Cupressus lusitanica Mill.) showed lower growth rates than the E species (Pinus hartwegii Lindl., Picea mexicana Martínez, Pseudotsuga menziesii (Mirb.) Franco and Abies vejari Martínez). Growth in W benefits mostly from high precipitation in the prior winter and current spring and it is limited by high temperatures in spring, whereas growth in the E showed similar but weaker responses. Furthermore, positive (negative) correlations were found in radial growth with the Niño 3.4 (SOI) and the PDO from the prior to current autumns, which were again stronger in absolute terms in the W than in the E regions, excepting SOI in summer. In the W, P. durangensis and C. lusitanica were the least and most responsive species to spring drought, respectively; whilst P. menziesii and A. vejari were very responsive to spring drought compared to P. hartwegii in the E. Our results suggest greater responsiveness to hydroclimate and atmospheric patterns in the W than in the E region. These findings allow better interpretations of future changes in growth and composition in Mexican conifer forests, considering that climate models forecast warmer spring conditions and increased water shortage.

Determinants of Commercial Tree Growing Among Smallholder Farmers in Nandi County, Kenya

Commercial Forestry sector contributes more than $600 billion to the global economy each year. Farm forestry is expected to contribute immensely to meeting materials needs for this sector and also provide ecosystem services. To support the tree growing by farmers, it is essential to understand the factors that influence commercial tree growing. The findings of a study to assess the current state of on-farm tree planting and the key variables influencing adoption of commercial tree growing on farms are reported in this paper. Cross sectional data on commercial tree growing was collected from two hundred and eighteen (218) households. Using semi-structured questionnaires with closed and open-ended questions, these households were systematically and randomly sampled from a population of 3633 farming households practicing agroforestry. Descriptive statistics, logit and binary logistic regression models, and qualitative analysis were applied. The findings show that socioeconomic factors such as age, education level, and income have a strong influence on commercial tree planting among small holder farmers in Nandi County. Older farmers are more likely than younger farmers to participate in commercial forestry as farmers because their employment opportunities are limited. Farmers with a high level of education are also more likely to practice commercial forestry because they have access to information and training. Farmers with a high off-farm income are more likely to grow commercial trees as a long-term return investment than farmers who rely entirely on their farms. According to the study, the majority of farmers preferred commercially planting exotic tree species, with 70.2 % planting Cupressus lusitanica and 69.7 % planting Eucalyptus saligna. The study recommends that farmers should be educated on species site matching, according to the study, because they were found planting Eucalyptus species even in riparian areas. In conclusion, farmers of various ages can be encouraged to use commercial tree farming and good management practices to generate more income

Plant-air partition coefficients for thirteen urban conifer tree species: Estimating the best gas and particulate matter associated PAH removers

Polycyclic Aromatic Hydrocarbons (PAHs) are an important class of pollutants which mostly come out from incomplete combustion of organic materials including fossil fuels. For this reason, they are often found at high concentrations in cities, contaminating air with their gas and particle phase. While European Union policies try to reduce their concentrations, huge efforts are still devoted to mitigate the pollution by PAHs. One such measure of mitigation is the use of plants in capturing PAHs and other chemicals due to the ability of leaves in filtering both gas and particle fractions. In this work thirteen conifer species among those frequently living in temperate and Mediterranean cities were selected and concentrations of 16 PAHs were measured in needles. The data for spruce were used to back-calculate air concentrations of PAHs which were later used to obtain specific equations of plant-air partition coefficient (KPA). The results showed that the difference in total PAH uptake between the most (Pinus pinaster) and the least (Picea abies) efficient tree was close to an order of magnitude. Looking to the capability of the different species in enriching the particulate matter (PM) associated fraction of PAHs on their needles, Pinus pinaster was instead the least important (3.4% of total PAHs), while Cupressus lusitanica was the most important (34% of total PAHs). The new KPA equations can be used to fine tune the PAH uptake of a specific amount of plant biomass on air concentration reduction.

English

The impacts of post-plantation management practices (urea, farm yard manure, and combinations of urea and farmyard manure) on the growth and survival rates of selected indigenous and exotic tree species Cordia africana, Olea europaea, Grevillea robusta, and Cupressus lusitanica at Sutte micro-watershed, Morode kebele in Mirab Abaya district, South Ethiopia were investigated. Soil samples were collected from the experimental site by the zigzag method at 10 m intervals from a 40 m by 80 m plot of land and analysed in Arba Minch University for their physical and chemical properties. Results showed that the mean soil texture was 94.12% sand, 4.66% silt and 1.19% clay, pH (6.95), and total nitrogen and available phosphorous were low, with corresponding results of 0.04% and 2.1 mg/L, respectively. Similarly, soil organic matter, available potassium and cation exchange capacity (CEC) were 2.8%, 1.33 mg/L and 13.2 mg/L, respectively. On the other hand, micronutrients like copper and zinc were 1.18 and 3.2 mg/L, respectively. The concentration of iron was 1.95 mg/L which no longer hampered the growth of planted tree seedlings. The growth of height and root collar diameter (RCD) of planted tree seedlings was measured, and the survival rate was calculated for each tree species for twelve months. Tree seedlings that received the combination of urea and farmyard manure (FYM) showed the longest height, RCD and the highest survival rate in C. lusitanica compared to other three planted seedlings species. The lowest growth in height and survival rate was recorded in O. europaea. The major limiting factors of the study included experimental site due to the presence of sandy soil and the toxicity of copper and zinc. However, these limitations were avoided by testing the soil before planting tree seedlings on selected sites and preparing plantation pits during dry seasons 2 to 3 months before the plantation period. Key words: Farmyard manure, growth, Mirab Abaya, post plantation management, survival rate, tree species, urea.