18 research outputs found

    Near Infrared Spectroscopy as non-destructive method for sorting viable, petrified and empty seeds of Larix sibirica

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    Larix sibirica Ledeb. is one of the promising timber species for planting in the boreal ecosystem; but poor seed lot quality is the major hurdle for production of sufficient quantity of planting stocks. Here, we evaluated the potential of Near Infrared (NIR) Spectroscopy for sorting viable and non-viable seeds, as the conventional sorting technique is inefficient. NIR reflectance spectra were collected from single seeds, and discriminant models were developed with Orthogonal Projections to Latent Structure - Discriminant Analysis (OPLS-DA). The computed model predicted the class membership of filled-viable, empty and petrified seeds in the test set with 98%, 82% and 87% accuracy, respectively. When two-class OPLS-DA model was fitted to discriminate viable and non-viable (empty and petrified seeds combined), the predicted class membership of test set samples was 100% for both classes. The origins of spectral differences between non-viable (petrified and empty) and viable seeds were attributed to differences in seed moisture content and storage reserves. In conclusion, the result provides evidence that NIR spectroscopy is a powerful non-destructive method for sorting non-viable seeds of Larix sibirica; thus efforts should be made to develop on-line sorting system for large-scale seed handling

    Commercial Eucalyptus Plantations with Taungya System: Analysis of Tree Root Biomass

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    The increasing demand for wood, fiber, and pulp, coupled with efforts to mitigate greenhouse gas emissions, has placed immense importance on the development of forest plantations. The rapidly growing human population faces shortages of food, particularly in the developing world where agricultural productivity is generally low. The taungya system, an age-old agroforestry practice involving the intercropping of crops with trees on the same unit of land, is opined as a win-win strategy to meet the need for wood products and food at the same time. In recent years, the taungya system has gained increasing attention from large forest companies as a tool and an opportunity to contribute to the social well-being of the local community. However, the effects of intercropping on the tree component are largely unexplored. Thus, this study was conducted to examine whether intercropping after 2 and 7 years has an effect on the root system of trees, thereby generating knowledge that supports evidence-based plantation management decisions involving the taungya system. To characterize the root system architecture, trenches were made on six young trees in both a pure Eucalyptus camaldulensis monoculture and intercropped stands (1111 trees/ha in both stands). To quantitatively estimate root biomass, a total of 324 soil cores (6 stands x 6 trees x 3 distances x 3 soil depths) were collected, and roots were sorted and dried to constant mass in an oven at 60 degrees C for 48 h. The root dry mass data were subjected to analysis of variance to examine the significant effects of intercropping, spacing, and stand age. The results show that the root system of E. camaldulensis was mainly confined to shallow depth but well elongated horizontally in both pure and intercropped stands with 4-6 thick lateral roots. The intercropping of rice/cassava with eucalypt had no effect on the total root dry mass of the tree component (p > 0.05) irrespective of the plantation spacing (5 m x 2 m or 9 m x 1 m); however, root biomass decreased with increasing horizontal distance from the tree base and in deeper soil layers, particularly for trees in young stands. The effects of spacing between trees, wide (5 m x 2 m) versus narrow (9 m x 1 m), on root dry mass were dependent on the horizontal and vertical distribution of the root system, and root biomass appeared to be higher at 40 cm soil depth for the stand with wide spacing between trees than for stands with narrow spacing. Root biomass was larger for older rather than younger trees in both monoculture and intercropped stands, suggesting the lack of a carry-over effect of intercropping on root biomass. In conclusion, this study provides evidence in support of intercropping as a win-win strategy to meet the short-term needs of food production while producing wood in the end. As root biomass varies with horizontal distribution, further research is recommended to test buffer zones between trees and crops other than 1m, which is currently used

    Regeneration Status and Role of Traditional Ecological Knowledge for Cloud Forest Ecosystem Restoration in Ecuador

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    The importance of forests for biodiversity conservation has been well recognized by the global community; as a result, conservation efforts have increased over the past two decades. In Ecuador, the lack of integrated information for defining and assessing the status of local ecosystems is a major challenge for designing conservation and restoration plans. Thus, the objectives of this study were (1) to examine the regeneration status of cloud forest remnants, some of which had experienced past human disturbance events, (2) to explore a local rural community's traditional ecological knowledge (TEK) relevant for restoration and (3) to investigate the integration between TEK and ecological science-based approaches. A survey of regeneration status was conducted in four remnants of cloud forests (n = 16) in Cosanga, Napo Province, in the Andes of northeastern Ecuador. The species of young trees (0.5-5 m height) were identified over 0.16 ha. In-depth interviews of individuals from local communities (n = 48) were conducted to identify socio-ecologically important native species. The results showed significant differences (p < 0.001) in species richness and the stem density of seedlings and saplings in gaps. The stem density of Chusquea sp., a bamboo species, explained 63% of the variation in species richness and 48% of the variation in the abundance of seedlings and saplings between plots. Informants cited 32 socio-ecologically important species, of which 26 species were cited as sources of food and habitats for wildlife. The ranking of species based on a relative importance index and a cultural value index-taking into account both the spread of knowledge among local informants and the multiplicity of uses-revealed that Hyeromina duquei, Citharexylum montanum, Eugenia crassimarginata and Sapium contortum were traditionally the most valuable species for both humans and wildlife. Informants also recommended 27 species for future planting, of which 19 species were amongst the rarest species in the regeneration survey. In conclusion, the results demonstrate a synergy between TEK and ecological science-based approaches (regeneration survey) to natural ecosystem research. Thus, traditional ecological knowledge can provide insights into ecosystem-plant-animal interaction, and to identify native species useful for both humans and wildlife for forest restoration projects to reconnect isolated cloud forest fragments

    Physico-chemical characteristics and heavy metal concentrations of copper mine wastes in Zambia: implications for pollution risk and restoration

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    Soil characterization is a vital activity to develop appropriate and effective restoration protocols for mine wastelands while insights into the total content of heavy metals in the soil is an important step in estimating the hazards that the metals may pose to the vital roles of soil in the ecosystem. This study addressed the following research questions: (1) To what extent do the physico-chemical characteristics vary between mine waste sediments and the nearby forest soil? (2) Are the concentrations of heavy metals high enough to be considered as toxic? and (3) Are heavy metals present in mine waste sediments potential sources of pollution? We hypothesized that the physico-chemical characteristics of mine waste sediments are less favorably for plant establishment and growth while the concentrations of heavy metals are very high, thus restricting the success of revegetation of mine waste lands. Mine waste sediments were sampled following a diagonal transect across tailings dams, overburden dump sites and the local forest soil from the top layer (0-20 cm) using a closed auger. Samples were analyzed for arsenic, barium, lead, cadmium, cobalt, copper, chromium, nickel, vanadium, and zinc as well as for soil physico-chemical properties. The mine waste sediments were dominated by silt whilst the forest soil by sand particles, with significantly high bulk density in the former. Both the forest soil and overburden sediments were acidic than the alkaline tailings dam sediment. Total organic carbon and nitrogen contents were significantly low in mine wasteland substrates but the concentration of Ca and Mg were significantly higher in tailings dam substrate than the forest soil. The concentrations of available P, K and Na were similar across sites. The mean concentrations of heavy metals were significantly (p &lt; 0.01) higher in mine waste sediments than the forest soil; except for cadmium (p = 0.213). The order of contamination by heavy metals on the tailings was Cu > Co > Ba > Ni > As > Zn > Pb > Cr > V > Cd, and that on the overburdens was Cu > Co > Ba > Ni > Zn > Cr > Pb > V > As > Cd. The pollution load index (PLI) was nearly twice higher for the tailings dam (8.97) than the overburden (5.84). The findings show that the copper mine wastes (the tailings dams and overburden waste rock sites) are highly contaminated by heavy metals; which, in turn, might pose serious hazards to human health and agricultural productivity. In addition, poor macro-nutrient availability, substrate compaction and soil acidity (particularly on overburden sites) coupled with toxic level of heavy metals would be the main challenges for successful phytostabilization of copper mine wastelands

    Single seed Near Infrared Spectroscopy discriminates viable and non-viable seeds of Juniperus polycarpos

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    A large quantity of non-viable (empty, insect-attacked and shriveled) seeds of Juniperus polycarpos (K. Koch) is often encountered during seed collection, which should be removed from the seed lots to ensure precision sowing in the nursery or out in the field. The aims of this study were to evaluate different modelling approaches and to examine the sensitivity of the change in detection system (Silicon-detector in the shorter vis-a-vis InGsAs-detector in the longer NIR regions) for discriminating non-viable seeds from viable seeds by Near Infrared (NIR) spectroscopy. NIR reflectance spectra were collected from single seeds, and discriminant models were developed by Partial Least Squares - Discriminant Analysis (PLS-DA) and Orthogonal Projection to Latent Structures - Discriminant Analysis (OPLS-DA) using the entire or selected NIR regions. Both modelling approaches resulted in 98% and 100% classification accuracy for viable and non-viable seeds in the test set, respectively. However, OPLS-DA models were superb in terms of model parsimony and information quality. Modelling in the shorter and longer wavelength region also resulted in similar classification accuracy, suggesting that prediction of class membership is insensitive to change in the detection system. The origins of spectral differences between non-viable and viable seeds were attributed to differences in seed coat chemical composition, mainly terpenoids that were dominant in non-viable seeds and storage reserves in viable seeds. In conclusion, the results demonstrate that NIR spectroscopy has great potential as seed sorting technology to upgrade seed lot quality that ensures precision sowing

    Factors influencing people's participation in the forest management program in Burkina Faso, West Africa

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    In attempts to foster sustainable forest management practices, participation of local communities has become widely recognized as a better alternative than the traditional protectionist approach. This paper analyzed factors influencing local people's participation in forest management program in Sissili and Ziro provinces, southern Burkina Faso based on data collected through a household survey of 165 members of forest management groups using factor analysis and multiple regression. Factor analysis resulted in a three-factor solution, which accounted for 64.82% of the total variance. Participation in decision-making, followed by participation in forest conservation and economic benefits were found to be the main factors influencing participation in the forest management program. Gender, household size, income source, land tenure status and technical assistance also appeared to influence members' participation in the program. The results indicate that participatory management program can be enhanced by changing the administrative structure of forest management groups in order to empower members in decision-making processes. In addition, increasing women's participation and more equitable benefit-sharing among user groups are essential in improving the success of the participatory forest management program. Thus, policies reforms to improve the structure of the forest management groups and to establish equitable benefit-sharing mechanisms are essential to improve the participation of local people in the forest management program and, hence, require immediate attention.Community forest management Collective action Participation Forest governance

    Application of near infrared spectroscopy for authentication of Picea abies seed provenance

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    eISSN: 1573-5095Authentication of seed provenance is an importance issue to avoid the negative impact of poor adaptation of progenies when planted outside their natural environmental conditions. The objective of this study was to evaluate the potential of near infrared (NIR) spectroscopy as rapid and non-destructive method for authentication of Picea abies L. Karst seed provenances. For this purpose, five seed lots from Sweden, Finland, Poland and Lithuania each were used. NIR reflectance spectra were recorded on individual seeds (n = 150 seeds × 5 seed lots × 4 provenances = 3000 seeds) using XDS Rapid Content Analyzer from 780 to 2500 nm with a resolution of 0.5 nm. Classification model was developed by orthogonal projection to latent structures-discriminant analysis. The performance of the computed classification model was validated using two test sets—internal (the same seed lots as the model but excluded during model development; n = 600 seeds) and external (seed lots not included in the model; n = 1158 seeds). For the internal test, the model correctly recognized 99% of Swedish, Finnish and Polish samples and 97% of Lithuanian seeds. For the external test samples, the model correctly assigned 81% of Swedish, 96% of Finnish, 98% of Lithuanian and 93% of Polish seeds to their respective classes. The mean classification accuracy was 99 and 95% for internal and external test set, respectively. The spectral differences among seed lots were attributed to differences in chemical composition of seeds, presumably fatty acids and proteins, which are the dominant storage reserves in P. abies seeds. In conclusion, the results demonstrate that NIR spectroscopy is a very promising method for monitoring putative seed provenances and in seed certificationVytauto Didžiojo universitetasŽemės ūkio akademij

    Regeneration of five Combretaceae species along a latitudinal gradient in Sahelo-Sudanian zone of Burkina Faso

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    • Seedling density and the regeneration mechanisms of five tree species, Anogeissus leiocarpa, Combretum aculeatum, Combretum micranthum, Combretum nigricans, and Pteleopsis suberosa were investigated in relation to latitudinal gradient across the Sahelo-Sudanian zone of West Africa. • Data were collected on 461 quadrats (2m × 5m) laid out every 30 m on transect lines through Combretaceae communities at four latitudinal positions. Regeneration mechanisms were determined by excavating the below ground root system and assessing basal and aerial sprouts. • The results showed a significant species × latitudinal position effect on the total density of seedling populations, and the density of single- and multi-stemmed individuals (p < 0.001). C. aculeatum and C. micranthum were abundant in the North-Sahelian sector, C. nigricans and P. suberosa in the Sudanian sector and A. leiocarpa across a wide range from the South-Sahelian to South-Sudanian sectors. In general, 58% of the seedlings were regenerated asexually (as coppice, water sprout, layer, and root sucker) while 42% were sexual recruits (as true seedling and seedling sprouts). The proportion of vegetatively propagated seedlings increased with increasing latitude for all species except C. micranthum, for which a clear decreasing trend was observed. The relative importance of the different regeneration mechanisms varied among species: seedling sprouts were important for A. leiocarpa, C. aculeatum and C. nigricans, coppice for C. micranthum and sucker for P. suberosa • The significant interaction observed between species and latitudinal position highlights the importance of accurate species-site matching to ensure successful restoration of degraded areas in the Sahelo-Sudanian zone. Inter-species differences in regeneration mechanism could be related to their biology and ecological adaptation to the site-specific biotic and abiotic factors

    data_Derroire_et_al_2016_Oikos

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    The provided data give the values of diversity and similarity indices for trees and shrubs, the successional age of the plot and values for environmental factors for 829 plots of 13 chronosequences in successional tropical dry forests used in the meta-analyses presented in the paper
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