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The Ecology and Management of Non-Timber Forest Resources

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Abstract

This report summarizes the current state of knowledge on the ecology of non-timber resources and outlines a series of management recommendations for their sustainable harvest. The discussion is divided into four chapters. Chapter I summarizes the basic characteristics of tropical plant populations that limit the nature and intensity of resource exploitation. Chapter II discusses the potential long-term ecological impacts resulting from the selective harvest of different plant tissues. Chapter III outlines the basic inventory and yield data needed to develop a program of sustainable resource use. Chapter IV provides an overview of conventional and indigenous forms of forest management and proposes a general sequence of silvicultural operations for enhancing the regeneration, growth, and productivity of different non-timber forest resources.

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... El análisis de la proporción entre categorías de edad en las diferentes parcelas fue relevante para interpretar la viabilidad biológica y los niveles de regeneración de la especie en las distintas poblaciones. Peters (1996) describió las tendencias de la estructura poblacional en bosques tropicales, que pueden ajustarse a tres tipos de curvas. Las poblaciones de las parcelas estudiadas en la ROP se ajustaron a los tipos de curva I y III. ...
... El análisis de la población es una herramienta extremadamente útil para orientar actividades de manejo de especies arbóreas y, quizás lo más importante, para evaluar el impacto de la extracción de recursos. Estas tres curvas, al encontrarse muy relacionadas con el estado de regeneración de las poblaciones, pueden variar frente a cambios en las condiciones ambientales; de manera que se pueda pasar de curva tipo I al III o al II (Peters, 1996). La gran producción de plántulas (aun de simientes) y disminución de individuos a medida que van avanzando en edad fueron constatadas también en otras poblaciones de palmeras tanto de pastizales como de bosque (Lozada & Moraes, 2013;González et al., 2012;Lunazi, 2009;Lorenzi;Barilani, 2002). ...
... La Figura 7 representa los valores medios para plántulas y las demás clases etarias para toda la región, tomando los sitios como subpoblaciones de una población. Se observa la curva de supervivencia resultante es una curva tipo I, J invertida (Peters, 1996). ...
... Population structure is the numerical distribution of individuals of different size or age within a population at a given moment of time (Peters, 1996). To determine the population structure of A. senegal and associated species, all individuals of the species encountered in the quadrats were arbitrarily grouped by 4-cm diameter classes (0 -4 cm, 4 -8 cm, 8 -12 cm…52 -56) and by 2-m height classes (0 -2 m, 2 -4 m, 4 -6 m …26 -28). ...
... The histograms were classified into three of the most common size-class distributions exhibited by tropical tree populations. These are Type I (displays a greater number of small trees than large trees, and an almost constant reduction in numbers from one size to the next), Type II (shows a characteristic of species that has discontinuous or periodic recruitment) and Type III (reflects a species whose regeneration is severely limited for some reason) (Peters, 1996). ...
... The population structure of A. senegal, Type I size class-distribution, (as the types are described in the materials and methods section) is characteristic of shade-tolerant canopy trees that maintain a more or less constant rate of recruitment. There is a large probability that the death of an adult tree will be replaced by the growth of individuals from the smaller size classes and it is considered by many authors the ideal of a stable, self-maintaining plant population (Peters, 1996). But as seen in the histograms of the present study, even though there is a positive regeneration for the species, it has small number of individuals in the higher diameter and height classes due to the reasons discussed at the population structure of the vegetation. ...
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Ethiopian Rift Valley, one of the vast dryland areas in Ethiopia, is facing serious problems of degradation due to unsustainable vegetation harvest for fuelwood and agricultural land expansion. Thus, there is a need for urgent measure to abate the destruction of this susceptible ecosystem. Managing the woodlands to offer economic incentive to the locals is probably a viable and lasting strategy to discourage deforestation. One of the options to provide economic incentive for the Rift Valley dryland ecosystem of Ethiopia is the production of gum arabic from A. senegal species, which is one of the conspicuous element in the vegetation of the area. Despite the natural occurrence of A. senegal in this woodland, no studies have assessed the status of the population of the species nor the quality of gum it produces. Recently, we investigated both the population status and gum arabic quality of the A. senegal resources in this Rift Valley area of Ethiopia. The result showed that density, abundance and importance value index for A. senegal was high in the various land covers/land use types assessed. The population structure of A. senegal also showed large numbers in the lower classes (good regeneration) but few individuals in the higher size classes, which may be due to the high cut off the mature trees for firewood and charcoal. The physicochemical characteristics of gum arabic collected from A. senegal trees in the central Rift Valley of Ethiopia fit very well with gum arabic qualities of commerce from known destinations such as the Sudan and also to international standards in all aspects, showing promising potential for commercialization. Therefore, if promoted for commercial tapping, gum based utilization of the Rift Valley dryland may not only rehabilitate the ecosystem but also will offer a sustainable development of the local and national economy while contributing to biodiversity conservation, combat desertification and contribute to control of global climate change. The quality of A. senegal as agroforestry tree may also offer the chance to integrate it with other land development option for the area such as animal husbandry and thus lead to integrated development.
... El análisis de la proporción entre categorías de edad en las diferentes parcelas fue relevante para interpretar la viabilidad biológica y los niveles de regeneración de la especie en las distintas poblaciones. Peters (1996) describió las tendencias de la estructura poblacional en bosques tropicales, que pueden ajustarse a tres tipos de curvas. Las poblaciones de las parcelas estudiadas en la ROP se ajustaron a los tipos de curva I y III. ...
... El análisis de la población es una herramienta extremadamente útil para orientar actividades de manejo de especies arbóreas y, quizás lo más importante, para evaluar el impacto de la extracción de recursos. Estas tres curvas, al encontrarse muy relacionadas con el estado de regeneración de las poblaciones, pueden variar frente a cambios en las condiciones ambientales; de manera que se pueda pasar de curva tipo I al III o al II (Peters, 1996). La gran producción de plántulas (aun de simientes) y disminución de individuos a medida que van avanzando en edad fueron constatadas también en otras poblaciones de palmeras tanto de pastizales como de bosque (Lozada & Moraes, 2013;González et al., 2012;Lunazi, 2009;Lorenzi;Barilani, 2002). ...
... La Figura 7 representa los valores medios para plántulas y las demás clases etarias para toda la región, tomando los sitios como subpoblaciones de una población. Se observa la curva de supervivencia resultante es una curva tipo I, J invertida (Peters, 1996). ...
... La evaluación de la sostenibilidad incluye información de la estructura poblacional (Paniagua 1998, Bernal & Galeano 2013. Según Peters (1996) una población podría presentar tres diferentes tipos de curvas poblacionales: la curva de tipo 1 o "J" invertida que muestra niveles constantes de regeneración; la curva de tipo 2 característica de especies con niveles discontinuos de regeneración y la curva de tipo 3 característica de especies con un nivel de regeneración severamente limitado. ...
... Estructura poblacional Se registraron 540 palmeras en los tres sitios de aprovechamiento (Sapacani, Saukela y La Plazuela) con cinco categorías de crecimiento. La estructura poblacional de las cinco categorías de crecimiento corresponde una curva de tipo 2 según lo planteado por Peters (1996), que se caracteriza por tener un nivel discontinuo de regeneración. Primero se observa un descenso de los individuos en las primeras categorías, y después un ascenso hacia los individuos pre-adultos (Fig. 4a). ...
... Para C. pityrophyllum se delimitaron cinco categorías de crecimiento, según con lo propuesto por Anthelme et al. Para Ceroxylon pityrophyllum en Bolivia es la primera vez que se realiza esta división de categorías de crecimiento, la curva poblacional que se generó es parecida a la de tipo 2 según (Peters 1996), es una población que tiene niveles discontinuos de regeneración, esto probablemente por efecto de actividades de extracción forestal y ganadería que son comunes en la región o apertura de senderos que se observó en los sitios relevados donde se cortan troncos de Cedrela odorata (Meliaceae) para ser vendidos los cuales se encuentran cerca de donde se cortan las hojas de las palmeras o también estos sitios podrían verse influenciada por las características del aprovechamiento de las hojas para Domingo de Ramos. ...
Article
Full-text available
The use of Ceroxylon pityrophyllum or "Ramo palm" in Bolivia is the weaving of leaves during "Palm Sunday"; because it is a seasonal activity, distribution and harvesting categories are unknown. The objective of the work was to evaluate the population structure, regeneration, density and spatial distribution of individuals, as well interpret the marketing chain in the city of La Paz. The field work was carried out between 2018-2019 in traditional harvesting sites (Saukela, La Plazuela and Sapacani) in Lambate (Sud Yungas, Irupana province). To evaluate the population structure and spatial distribution the plot-variance method was used in 30 plots of 10 x 10 m with records of total height, DAP, number of leaves, pinnae and reproductive structures per individual. Semi-structured interviews were conducted with 60 sellers in 18 churches in order to record information about used palm species, their procedence, purchase-sale prices and types of fabric they make. 540 individuals were counted in five growth categories: seedlings (158), juveniles 1 (114), juveniles 2 (93), pre-adults (153) and adults (22), with a type 2 population curve. It shows a pattern spatial aggregate in the three evaluated sites. Four stages in the commercialization chain were identified: a) Access and selection of the leaves, b) Collection and transport and of the leaves, c) Artisan transformation and d) Sale; and, six links: 1) forest supplier, 2) harvester, 3) transponer, 4) intermediary sellers, 5) sellers in the churches, and 6) buyer or consumer. This information will serve as a basis to guide the proper harvesting of leaves in management plans and to guide their commercialization.
... El análisis de la proporción entre categorías de edad en las diferentes parcelas fue relevante para interpretar la viabilidad biológica y los niveles de regeneración de la especie en las distintas poblaciones. Peters (1996) describió las tendencias de la estructura poblacional en bosques tropicales, que pueden ajustarse a tres tipos de curvas. Las poblaciones de las parcelas estudiadas en la ROP se ajustaron a los tipos de curva I y III. ...
... El análisis de la población es una herramienta extremadamente útil para orientar actividades de manejo de especies arbóreas y, quizás lo más importante, para evaluar el impacto de la extracción de recursos. Estas tres curvas, al encontrarse muy relacionadas con el estado de regeneración de las poblaciones, pueden variar frente a cambios en las condiciones ambientales; de manera que se pueda pasar de curva tipo I al III o al II (Peters, 1996). La gran producción de plántulas (aun de simientes) y disminución de individuos a medida que van avanzando en edad fueron constatadas también en otras poblaciones de palmeras tanto de pastizales como de bosque (Lozada & Moraes, 2013;González et al., 2012;Lunazi, 2009;Lorenzi;Barilani, 2002). ...
... La Figura 7 representa los valores medios para plántulas y las demás clases etarias para toda la región, tomando los sitios como subpoblaciones de una población. Se observa la curva de supervivencia resultante es una curva tipo I, J invertida (Peters, 1996). ...
Article
Full-text available
Densidad de plántulas en poblaciones de Butia paraguayensis (Barb. Rodr.) L.H. Bailey en Paraguay. Se presentan los resultados parciales de la tesis "Factores ambientales que determinan los patrones poblacionales de Butia paraguayensis (Barb. Rodr.) L.H. Bailey (Jata'i) en la Región Oriental del Paraguay", referentes a la densidad de plántulas hallada en el estudio, los factores ambientales que la determinan y la capacidad autoregenerativa de la población. Para el conteo de los individuos se establecieron 14 parcelas de 10 x 100 m, en siete Departamentos de la Región Oriental del país, y dentro de ellas se demarcaron 280 sub-parcelas de regeneración de 0,25 x 4 m para el conteo de plántulas. Se registraron variables de manejo, clima y suelo. Los análisis estadísticos se realizaron en "Biodiversity R". Se exploraron los datos mediante una matriz de auto-correlaciones, utilizando el coeficiente de Pearson. Se pre-seleccionaron aquellas variables predictoras con un coeficiente < 0,6 entre ellas; y una correlación ≥ 0,3 con relación a la variable respuesta. De estas se seleccionaron todas aquellas que, mediante una regresión simple, o gráficos de dispersión, mostraron una fuerte correlación con la variable respuesta o que, con correlación débil, tuvieran significancia biológica conocida. Fueron utilizados Modelos Generales Linearizados (binomiales negativos) para evaluar la influencia de las variables en las densidades. La densidad promedio de plántulas en 20 m 2 fue de 6 individuos. La población de B. paraguayensis resultó ser auto-regenerativa. La variabilidad de la densidad en las parcelas dependió de variaciones en las concentraciones de P, Fe, pH, materia orgánica y porcentaje de arena, que explicaron en un 95% la diferencia de densidades de plántulas en los sitios muestreados (Devianza explicada). En las pruebas de regresión simple la cobertura vegetal, uso del suelo y último año de quema, tuvieron influencia, pero en el modelo no resultaron ser estadísticamente significativos. Estos factores deberán ser mejor estudiados. Ninguna variable meteorológica presentó influencia significativa sobre la densidad de plántulas. Palabras clave: Butia paraguayensis, Jata'i, modelos generales linearizados, patrones poblacionales Seedling density in populations of Butia paraguayensis (Barb. Rodr.) L.H. Bailey in Paraguay. Partial results of the thesis "Environmental factors that determine the population patterns of Butia paraguayensis (Barb. Rodr.) LH Bailey (Jata'i) in the Eastern Region of Paraguay", referring to the environmental factors that influence the density of seedlings found therein, are presented in this publication. For this, 14 plots of 10 x 100 m were established in seven Departments of the Eastern Region of the country, and within them 280 regeneration sub-plots 0,25 x 4 m were demarcated for seedling count. Management, climate and soil variables were recorded. Statistical analyses were performed in "Biodiversity R". Data were explored by means of a self-correlation matrix using the Pearson coefficient. Independent variables with a Pearson coefficient <0,6 between each other and a correlation ≥ 0,3 in relation to the dependent variables were pre-selected. From these, the ones that, showed a strong correlation with the dependent variable through simple regression were selected. General Linearized Models (negative binomials) were used to assess the influence of the variables on densities. The average seedling density in 20 m 2 was 6 individuals. The B. paraguayensis population was found to be self-regenerating. The variability of the density,in the plots depended on variations in the concentrations of P, Fe, pH, organic matter and percentage
... (Fotografía de Fabrice Edourad) del principio del manejo adaptativo y establecen los niveles de cosecha según dicten la observación y la experiencia, las cuales se complementan con la información obtenida del monitoreo del impacto de la cosecha a través del tiempo. Peters (1996) denomina este proceso como "aproximación sucesiva". Pocas operaciones tienen el dominio técnico, el equipo, el tiempo y los fondos suficientes para llevar a cabo análisis científicos profundos. ...
... La mayoría de las guías existentes para el manejo forestal tienen que ver con objetivos madereros. A pesar de su larga historia de recolección, hay pocos ejemplos de buenos planes de manejo para PFNM recolectados comercialmente, aunque están en proceso esfuerzos por desarrollar regímenes de manejo efectivos y asequibles (Peters 1996). Por ejemplo, las nueces de Brasil han sido recolectadas en Bolivia por más de 30 años, pero el primer plan de manejo para este producto fue diseñado hasta 1998 bajo el auspicio del Proyecto de Manejo Forestal Sostenible de Bolivia (BOLFOR). ...
... En la India, la alarma causada por la rápida reducción de la base de recursos y la disminución en la producción de bienes, como las hojas de tendu y el mango silvestre, catalizó el interés de las comunidades en el auto monitoreo. En Indonesia los recolectores de ratán vieron en el monitoreo una de cosecha y ayudar a monitorear las dinámicas de las poblaciones posteriormente a la cosecha (Peters 1996;Cunningham 2001;Hall y Bawa 1993), las comunidades rurales tienden a crear métodos propios para monitorear el vigor de las plantas de las que dependen. Estos sistemas ideados localmente pueden proporcionar información valiosa para los ecologistas y administradores forestales. ...
... Determining sustainable harvest levels for NTFPs is difficult and has best been accomplished through years of field observation and experimentation termed 'adaptive management.' Most operations applying for NTFP certification rely upon the principal of adaptive management and set harvest levels based upon observation and experience, supplemented by information gained from monitoring the impact of harvesting over time, what Peters (1996) ...
... Key characteristics of species such as life span, sprouting ability, habitat and capacity to regenerate determine their vulnerability or resilience. By understanding the characteristics of species and their habitats, it is possible to predict responses to elevated levels of harvesting (Peters 1994(Peters , 1996Cunningham 2000). Root and bark harvest may be particularly problematic, especially from longer-lived species or those without the ability to resprout. ...
... "Third party" certification auditors and ecologists tend to demand exacting scientific studies prior to accepting traditional or indigenous monitoring mechanisms. While certain tools have been designed to set harvest levels and to help monitor population dynamics post-harvest (Hall and Bawa 1993;Peters 1996;Cunningham 2001), rural communities have generally devised their own methods to monitor the vigor of the plants they rely upon. Such locally devised systems can provide valuable information to ecologists and forest managers. ...
... La evaluación de la sostenibilidad incluye información de la estructura poblacional (Paniagua 1998, Bernal & Galeano 2013. Según Peters (1996) una población podría presentar tres diferentes tipos de curvas poblacionales: la curva de tipo 1 o "J" invertida que muestra niveles constantes de regeneración; la curva de tipo 2 característica de especies con niveles discontinuos de regeneración y la curva de tipo 3 característica de especies con un nivel de regeneración severamente limitado. ...
... Estructura poblacional Se registraron 540 palmeras en los tres sitios de aprovechamiento (Sapacani, Saukela y La Plazuela) con cinco categorías de crecimiento. La estructura poblacional de las cinco categorías de crecimiento corresponde una curva de tipo 2 según lo planteado por Peters (1996), que se caracteriza por tener un nivel discontinuo de regeneración. Primero se observa un descenso de los individuos en las primeras categorías, y después un ascenso hacia los individuos pre-adultos (Fig. 4a). ...
... Para C. pityrophyllum se delimitaron cinco categorías de crecimiento, según con lo propuesto por Anthelme et al. Para Ceroxylon pityrophyllum en Bolivia es la primera vez que se realiza esta división de categorías de crecimiento, la curva poblacional que se generó es parecida a la de tipo 2 según (Peters 1996), es una población que tiene niveles discontinuos de regeneración, esto probablemente por efecto de actividades de extracción forestal y ganadería que son comunes en la región o apertura de senderos que se observó en los sitios relevados donde se cortan troncos de Cedrela odorata (Meliaceae) para ser vendidos los cuales se encuentran cerca de donde se cortan las hojas de las palmeras o también estos sitios podrían verse influenciada por las características del aprovechamiento de las hojas para Domingo de Ramos. ...
Article
Full-text available
Resumen El uso de Ceroxylon pityrophyllum o "palma de ramo" en Bolivia es el tejido de hojas durante "Domingo de Ramos"; debido a que es una actividad estacional, se desconoce su distribución y categorías cosechables. El objetivo del trabajo fue evaluar la estructura poblacional, regeneración, densidad y distribución espacial de los individuos, así como interpretar la cadena de comercialización en la ciudad de La Paz. El trabajo de campo se realizó entre 2018-2019 en sitios tradicionales de cosecha (Saukela, La Plazuela y Sapacani) de Lambate (Sud Yungas, provincia Irupana). Para evaluar la estructura poblacional y distribución espacial se utilizó el método parcela-varianza en 30 parcelas de 10 x 10 m con registros de altura total, DAP, número de hojas, pinnas y estructuras reproductivas por individuo. Se realizaron entrevistas semiestructuradas a 60 vendedores en 18 iglesias sobre venta, procedencia, precios y tipos de tejido. Se contabilizaron 540 individuos en cinco categorías de crecimiento: plántulas (158), juveniles 1 (114), juveniles 2 (93), pre-adultos (153) y adultos (22), con una curva poblacional de tipo 2. Muestra un patrón espacial agregado en los tres sitios evaluados. Se identificaron cuatro etapas en la cadena de comercialización: a) Acceso y selección de las hojas, b) Acopio y transporte y de las hojas, c) Transformación artesanal y d) Venta; y, seis eslabones: 1) proveedor, 2) cosechador, 3) transportista, 4) vendedores intermediarios, 5) vendedores en las iglesias, y 6) comprador o consumidor. Esta información servirá de base para orientar la adecuada cosecha de hojas en planes de manejo y para guiar su comercialización. Palabras clave : Cadena de comercialización, Distribución espacial, Estructura poblacional, Palma de ramo. Abstract The use of Ceroxylon pityrophyllum or "Ramo palm" in Bolivia is the weaving of leaves during "Palm Sunday"; because it is a seasonal activity, distribution and harvesting categories are unknown. The objective of the work was to evaluate the population structure, regeneration, density and spatial distribution of individuals, as well interpret the marketing chain in the city of La Paz. The field work was carried out between 2018-2019 in traditional harvesting sites (Saukela, La Plazuela and Sapacani) in Lambate (Sud Yungas, Irupana province). To evaluate the population structure and spatial distribution the plot-variance method was used in 30 plots of 10 x 10 m with records of total height, DAP, number of leaves, pinnae and reproductive structures per individual. Semi-structured interviews were conducted with 60 sellers in 18 churches in order to record information about used palm species, their procedence, purchase-sale prices and types of fabric they make. 540 individuals were counted in five growth categories: seedlings (158), juveniles 1 (114), juveniles 2 (93), pre-adults (153) and adults (22), with a type 2 population curve. It shows a pattern spatial aggregate in the three evaluated sites. Four stages in the commercialization chain were identified: a) Access and selection of the leaves, b) Collection and transport and of the leaves, c) Artisan transformation and d) Sale; and, six links: 1) forest supplier, 2) harvester, 3) transporter, 4) intermediary sellers, 5) sellers in the churches, and 6) buyer or consumer. This information will serve as a basis to guide the proper harvesting of leaves in management plans and to guide their commercialization.
... In the analysis of vegetation structure, the growth stages of trees as seedlings, saplings, and mature trees as well as the distribution of size classes within a population can be essential elements of diversity that permit or deny the likelihood of quick recovery after disturbances [12]. e status and dynamics of woody-tree populations can be examined by conducting a size class distribution and seedling and sapling counts [13,14]. Healthy natural populations with continuous regeneration exhibit an exponentially decaying size class distribution, whereby trees in smaller size classes are represented in greater numbers than in larger classes. ...
... e absence or rarity of seedlings can be considered an indication of a declining population. e population structure of a tree species is indicative of its history of past disturbance and can be used to predict its future status in the forest [13]. is study investigated the woody species diversity, structure, and regeneration status of the Agama Forest in Southwestern Ethiopia. ...
... Information on the population structure of a tree species indicates the history of the past disturbance to that species and the environment and, hence, is used to forecast the future trend of the population of that particular species [13]. Population structure is an extremely useful tool for orienting management activities and perhaps most important for assessing both the potential of a given resource and the impacts of resource extraction [13]. ...
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This study was conducted in Agama Forest in Kafa Zone, Southwestern Ethiopia, to assess species diversity, vegetation structure, and regeneration status of woody species. A systematic sampling technique was employed to collect vegetation data. Sixty (60) sample plots of 25 m × 25 m were laid at 300 m intervals all along ten grids interspaced 800 m apart. Sample plots of 25 m × 25 m were used to record DBH and H of all woody plant species reaching a DBH >2.5 cm and height >2 m. For the inventory of seedling and sapling, two subplots of 2 m × 5 m were used at the beginning and the end of the baseline on opposite sides of the main quadrat. Vegetation data such as DBH, height, seedling, and sapling density of woody species were recorded in each plot. Altogether, 72 woody plant species of 65 genera and 35 families were identified. Analysis of selected tree species showed diverse population structures. This study showed that small trees and shrubs dominated the Agama Forest, which revealed its status under a secondary regeneration stage. Study on the structure and regeneration of some woody species indicated that there are species that require urgent conservation measures. Sound management and monitoring, as well as maintenance of biodiversity and cultural and economic values of the forest, require conservation activities that encourage sustainable uses of the forest and its products.
... Woody plants can portray an Inverse Jshape pattern of population structure where there are more small woody plants than the larger ones characterized by abundant species with constant rejuvenation and recruitment. Besides, woody plants can display a bi-modal pattern of plant population structure indicative of plants which recruit seedlings in pulses such that there are discontinuities in the population structure resulting into a two layered vertical structure of a species [8]. Nonetheless, plants can display a decreasing/irregular pattern of plant population structure shaped by external disturbance in which regeneration is not keeping pace with mortality and most individuals are of the same size class or in some cases, there are no signs of seedling recruitment [9]. ...
... System in South-Western Uganda 54 The population structure patterns of woody plant species provide an important indicator of their conservation status. The inverse J shape pattern of population structure displayed by the certain trees and shrubs is typical of a self-sustaining population where seedlings are recruited continuously into bigger size classes [8]. In a sedentary grazing system in South-western Uganda, this could be attributed to improvement in land tenure which increased control of use of woody plant species. ...
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This study engaged 100 pastoralists and conducted a plant inventory in 13.5 ha of grazing lands to determine the locally useful indigenous woody plant species, their abundance and population structure in a sedentary grazing system in Southwestern Uganda. Through descriptive and inferential statistics, 40 shrubs and 30 tree species were identified. The species were useful sources of animal medicine (85.7%), human medicine (80%), fodder and firewood (57.1%), poles (50%), timber (42.9%), shade (24.3%), food (21.3%) and raw materials for crafts (10%). Albizia coriaria, Acacia hockii, Acacia sieberiana, Carissa edulis and Vernonia amygdalina were the major woody plants used. For food and fodder, the woody plants were only utilized during the dry season but for other purposes, the species were resorted to any season in the year. Plant inventory recorded 39 woody plant species. Acacia hockii and Rhus natalensis existed in all the ranches and were the most abundant species (29.4% and 10.9% respectively). The average plant density was 35 trees/shrubs-ha. Inverse J shape, bimodal but mostly irregular pattern were the population structure types displayed. Thus, for sustainable sedentary pastoralism in Uganda, use of indigenous woody plant species requires policy supported conservation and enrichment planting, building the capacity of pastoralists in propagation and aided natural regeneration techniques for woody plants and scientific analyses to strengthen diversified use of the major woody plant species.
... Population structure is the distribution of individuals of each species in arbitrarily to provide the overall regeneration profile of the study based on tree density, height, frequency, diameter at breast height, species importance value and basal area (Peters, 1996;Tesfaye et al., 2002;Shibru & Balcha, 2004). Information on population structure of a tree species indicates the history of the past disturbance to that species and the environment and hence, used to forecast the future trend of the population of that particular species (Peters, 1996). ...
... Population structure is the distribution of individuals of each species in arbitrarily to provide the overall regeneration profile of the study based on tree density, height, frequency, diameter at breast height, species importance value and basal area (Peters, 1996;Tesfaye et al., 2002;Shibru & Balcha, 2004). Information on population structure of a tree species indicates the history of the past disturbance to that species and the environment and hence, used to forecast the future trend of the population of that particular species (Peters, 1996). From the population dynamics point of view, examination of patterns of species population structure could provide valuable information about their regeneration and/or recruitment status as well as viability status of the population that could further be employed for devising evidence-based conservation and management strategies (Teketay, 2005;Tilahun et al., 2011). ...
... The DBH data of selected trees and shrubs were categorized into nine classes (1 = < 2 cm; 2 = 2-10 cm; 3 = 10-20 cm; 4 = 20-30 cm; 5 = 30-40 cm; 6 = 40-50 cm; 7 = 50-60 cm; 8 = 60-70 cm; 9 = > 70 cm), and the density of each species in each DBH class was calculated; the DBH class distributions were presented using histograms, i.e., density of individuals (Y-axis) plotted against diameter class (X-axis) (Peters 1996). Based on the pro le depicted in the population structures, the regeneration status of the selected woody species was determined. ...
... According to Curtis and McIntosh (1951), a given species is said to be dominant if it had the highest IVI value compared to other plant species within an area. In a very general sense, the higher the IVI value of a species, the more successful it is in that pariticular habitat (Peters 1996). Accordingly, Combretum molle, Olea europaea subsp. ...
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Background: The remaining natural forests of Ethiopia are only small patches mostly confined to inaccessible areas and sacred places. Fach forest is one of the remnant dry evergreen Afromontane forests (DAFs) in northwestern Ethiopia. There is lack of information on the vegetation ecology of the forest. Thus, the present study was conducted to investigate the floristic composition and diversity, population structure, regeneration status and socio-economic importance of Fach forest, and the anthropogenic factors affecting it. Methods: Vegetation data were collected from a total of 34 plots, measuring 20 m × 20 m (400 m²) each and established along line transects approximately at 100 m intervals. A general survey consisting of field observations, key-informant interviews and Focus Group Discussion (FGD) was used to collect socio-economic data. Results: A total of 230 vascular plant species belonging to 183 genera and 76 families were recorded from the study area, of which 45 (19.57%) were trees, 62 (26.97%) trees/shrubs, 37 (16.09%) shrubs, 13 (5.65%) woody climbers, 10 (4.35%) herbaceous climbers, and 63 (27.39%) herbs. The family with the highest number of species was Fabaceae (28 species, 12.17% of all species), followed by Asteraceae (18 species, 7.83%), Poaceae (13 species, 5.65%), and Acanthaceae and Euphorbiaceae (9 species each). The Shannon-Wiener diversity and evenness values of woody species were 3.53 and 0.72, and the total density and basal area 4938.24 individuals ha⁻¹ and 19.17 m² ha⁻¹, respectively. The species with the highest Importance Value Index (IVI) value was Combretum molle (25.26%), followed by Olea europaea subsp. cuspidata (21.19%), Dodonaea angustifolia (17.80%), and Calpurnia aurea (15.05%). The local communities were highly dependent on the forest for fuelwood, construction material, charcoal, timber and farm implements, as well as food (edible fruits), medicines, fodder, and bee forage. Fach forest is a protected area and contains sacred places, but at present it is dwindling mainly due to livestock grazing/browsing, tree cutting for various purposes, farmland expansion, rural settlements expansion, urbanization, fire incidences, and exotic species plantations at the expense of the natural forest, as well as soil erosion and climate change. Conclusions: Fach forest possesses high plant diversity and endemism. Woody species having low IVI values and poor regeneration status (as indicated by the Diameter at Breast Height [DBH] class distributions) need high priority for conservation. Fach forest has been maintained to the present-day through the combined indigenous (sacred grove) and modern (protected area system) conservation methods, but is now under increasing human pressure. Therefore, effective conservation and management interventions are urgently needed to ensure the long-term maintenance of the forest ecosystem, and benefit the local communities through sustainable utilization of the forest.
... Therefore, by reducing the structural and species diversity of a forest, logging and silvicultural treatments can also produce a number of largely as yet unknown ecological repercussions. These may include reductions in numbers of pollinators, seed dispersers, alterations in plant-herbivore relationships and the possibility that timber exploitation may ultimately produce conditions in which it is difficult for many forest species to regenerate (Peters, 1996). Some studies do exist which attempt to evaluate changes in community ecology variables with logging, damage, regeneration, and silvicultural treatments both for useful plant species and for the plant community as a whole (Salick et al., 1995;Peters 1996). ...
... These may include reductions in numbers of pollinators, seed dispersers, alterations in plant-herbivore relationships and the possibility that timber exploitation may ultimately produce conditions in which it is difficult for many forest species to regenerate (Peters, 1996). Some studies do exist which attempt to evaluate changes in community ecology variables with logging, damage, regeneration, and silvicultural treatments both for useful plant species and for the plant community as a whole (Salick et al., 1995;Peters 1996). ...
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Ethnobotanical and ecological studies were carried out to take inventory of the species used by the inhabitants surrounding the Subri River Forest Reserve for reproductive health care and to assess the ecological status of woody plant species of this reserve. The study was carried out between November 2005 and December 2006. Medical ethnobotanical knowledge was gathered from 80 inhabitants in 25, communities using questionnaires. Reproductive health conditions were categorized into 19 major conditions, some of which included abortion, breast cancer, miscarriage and sexual impotence; and 7 corporeal or body systems. A total of 185 medicinal plants species, distributed in 60 families and 155 genera were cited. The most cited species was Gouania longipetala (4.23%). Of these 185 species, 72.97% were woody, while 27.03% were herbaceous. The most frequently employed plant part was barks (32.49 %), followed by roots (29.95%) and leaves (21.32%). Phytosociological studies on woody species with girth of at least 10 cm were undertaken in 50 circular plots of 0.l ha, making a total of 5ha study area. A total of 128 species belonging to 104 genera and 45 families were encountered. The importance value indices of these species were generally low (0.28 to 20.09). Their distribution into Raunkiaer's frequency classes showed that 92.19% of the species were rare and none was common. There were high species diversity indices of Simpson (0.96) and Shannon-Weaver (4.00). Species evenness was also high (0.82). Only 57 (44.53%) of the woody species were cited for reproductive health conditions. The Relative Importance (RI), calculated from an ethnobotanical perspective, showed that approximately 28% of the 57 plant species were versatile. Alchomca cordifolia was the most versatile species for the reproductive health conditions. However, there was no significant (p>O.05) association between the RI and the phytosociological parameter values of the 57 woody medicinal species. Provisions of sustainable harvesting methods, adequate knowledge about forest management and cultivation among others, will ensure the conservation and sustainable use of these medicinal plants.
... The population structures were analyzed using histograms with the grouped diameter classes. It was constructed by using the density of individuals of each species (Y-axis) and categorized into ten diameters classes (X-axis) following [56] i.e. 1=< 2 cm; 2=2-5cm; 3=5 -1 0cm; 4=10 -1 5cm; 5=15-20cm; 6=20-25cm; 7=25-30cm; 8=30-35; 9=35-40; 10=> 40cm. The purpose of using size class distributions in diameter at breast height (DBH) is to investigate the regeneration status of the woody plant species [56]. ...
... It was constructed by using the density of individuals of each species (Y-axis) and categorized into ten diameters classes (X-axis) following [56] i.e. 1=< 2 cm; 2=2-5cm; 3=5 -1 0cm; 4=10 -1 5cm; 5=15-20cm; 6=20-25cm; 7=25-30cm; 8=30-35; 9=35-40; 10=> 40cm. The purpose of using size class distributions in diameter at breast height (DBH) is to investigate the regeneration status of the woody plant species [56]. ...
... Height and diameter frequency distribution of all tree and shrub species were employed to determine population structure of the vegetation. Each species encountered in a quadrat were grouped into a diameter class of 4 cm and height of 2 m and structure of the species were depicted using frequency histogram of both diameter and height class distributions following Peters (1996). ...
... According to previous studies (Silvertown, 1982;Silvertown and Doust, 1993;Mekuria et al., 1999;Alemnew Aleligne, 2001;Alemayehu Wassie, 2002;Getachew Tesfaye et al., 2002), a reverse J-shape distribution pattern was considered as an indication of stable This might be one of the most important reasons that made the species retard from its normal recruitment status. Sterculea setigera fell in J-shape distribution pattern, which is considered as reflection of severe limitation on the regeneration for some reason (Peters, 1996). This study noted that Sterculea setigera was one of the most important multipurpose tree species used for like fodder especially during the dry season at times when there is forage scarcity. ...
... A maioria das diretrizes existentes para manejo florestal trata de objetivos madeireiros. Apesar da longa história de coleta dos PFNMs, há poucos exemplos de bons planos de manejo para esses produtos coletados para fins comerciais, apesar de que, atualmente, há esforços maiores para o desenvolvimento de regimes de manejo eficazes e financeiramente acessíveis (Peters 1996). Por exemplo, há mais de 30 anos a castanhado-brasil é coletada na Bolívia, mas o primeiro plano de manejo para este produto só foi elaborado em 1998, com o patrocínio da Agência Norte-americana para o Desenvolvimento Internacional (Usaid) para o Projeto de Manejo Florestal Sustentável da Bolívia (Bolfor). ...
... O conhecimento e habilidades dos povos locais podem ajudar a resolver este problema, mas isto foge da meta da certificação independente por "terceiros". Enquanto certas ferramentas são desenhadas para estabelecer níveis de extração e ajudar a monitorar a dinâmica de populações pós-colheita (Peters 1996;Cunningham 2001;Hall e Bawa 1993), comunidades rurais têm de um modo geral inventado seus próprios métodos para monitorar o vigor das plantas das quais dependem. Esses sistemas inventados localmente podem oferecer valiosas informações aos ecologistas e manejadores. ...
... Data were analysed using descriptive statistics as well as Shannon-Weiner diversity and Important Value Indices (Peters, 1996). Classification of trees and natural regeneration into utilization classes followed Redhead (1971) while tree identification followed Keay (1989). ...
... H′= -∑ i =1 ( )………… (eqn. 1) where H' = Shannon index of diversity, pi = the proportion of importance value of the i th species (pi = ⁄ ), ni is the importance value index of i th species and N is the important value index of all the species. Importance Value Index (IVI) The sum of RDO, RD and RF gave the importance value index for each species (Peters, 1996). The index is use to express the share of each species in the tree community (Rajkumar and Parthasarathy, 2008) Basal Area Basal area for all trees was determined using ...
Article
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A diagnostic study on floristic and mammalian composition and diversity was conducted in an intensely logged Amahor Forest Reserve, Edo State, Nigeria. Tree height and girth (>30cm) were measured in 10 (50m x 40m) randomly located plots using Nikon Laser Rangefinder (Forestry 550) and girthing tape respectively while evaluation of natural regeneration was conducted in ten (10m x 10m) plots. Mammals were assessed within six (0.5km) line transects sited in existing and constructed trails using direct and indirect survey techniques. Data were analysed using descriptive statistics, Shannon-Weiner (H') diversity and Important Value indices. Results on floristic richness revealed 249 trees distributed among 70 species in 31 families while species diversity was 3.73. Ricinodendron heudelotii and Caesalpinioideae were the most important tree and family respectively. For wildlife, 80 individuals distributed among 21 species in 13 families were recorded while species diversity was 2.796. Cricetomys gabianus and Bovidae were the most important species and family respectively. Among the mammals, only two-the White-throated guenon and African white bellied pangolin-were classified "endangered" on the IUCN Red List. However, based the National Biodiversity classification approach, four species were 'endangered', three 'threatened' and two 'rare'. Regardless of the level of species erosion and ecosystem degradation, Amahor Forest Reserve has fairly rich soil seed and seedling banks of important timber tree species. It is imperative for Edo State Government to mobilize resources, engender and incentivize forest dependent communities; and provide an enabling policy for the rehabilitation of the landscape and its vanishing biodiversity through participatory approach.
... To determine the population structure, individuals of each species encountered were grouped in to a diameter class and structure of the species was shown using frequency class of diameter and height distribution. According to Peters [61] frequency class was important to interpret the indication of the regeneration status of the forest. ...
... In his review of NTFP literature, Belcher (2003) found many definitions of the terms ´NTFP´, ´forest´, and other related concepts. Belcher argued that the various terms are inconsistent, for they can include resources such as gravel and rocks, or services such as water provision, while other definitions may take into consideration both ´natural and managed forests´ (Peters 1996;Ros Tonen et al. 1998;Shanley et al. 2015). As Belcher (2003) argued, the terminology related to NTFPs is diverse and often contradictory and confusing, because there are so many different interests and priorities involved in NTFP management, production and commercialization. ...
Article
Broad reading of the literature on NTFPs in order to highlight key issues of NTFP management, their importance for rural livelihoods, and the implications for forest policy. It demonstrates the complexity of formulating an integrated framework for the understanding of NTFP management, especially as they affect forest policies. The scope is global, but with emphasis on Latin America. Human populations have depended on and used NTFPs for millennia. For a great number of rural (and also urban) inhabitants, particularly the poorest sectors, their use represents an important source of subsistence and income-generation. It has been suggested that the use of NTFPs can generate greater incomes than other productive land use options, such as timber extraction or cattle keeping. Some studies estimate that around 25% of the income of about one billion people around the world comes from NTFPs, although that implies that, by themselves, NTFPs do not represent a sufficient source of household income. Rather, they should be considered as part of a wider spectrum of rural livelihood strategies which include their importance as income safety nets and as reservoirs of cultural values and traditional knowledge. Furthermore, NTFPs have many ecological and social values related to forest ecosystems, well-being and conservation. This diversity of potential benefits has represented an obstacle for the creation of management and conservation policies. The intention of this paper is to tackle some of the most important issues raised in the literature on NTFPs, forest conservation and development, with an entry point in the alternative understandings and definitions of NTFP. The paper highlights some approaches intended to overcome perceived barriers for sustainable management of NTFPs and the well-being of their human users.
... Population structure data have long been used by foresters and ecologists to investigate the regeneration characteristics of tropical trees (Peters, 1996). Accordingly, it was found that C. myrrha showed reversed J-shape while C. guidotti showed type-2 stem distribution patterns. ...
Conference Paper
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Hardened resinous plant exudates such as gum acacias, gum olibanum, myrrh and opopanax were collected and traded for centuries both on the international and domestic markets in Ethiopia. Somali Regional State is one of the major administrative regions in the country endowed with gum and resin bearing resources. However, regardless of the significant ecological and economic role to the pastoral poor and nation at large, only little documentation is available on the population status and economic contribution of the gum resin sector in draylands of the region. Hence, a study aiming at investigating current population status of Commiphora myrrha and Commiphora guidotti in particular and the role of myrrh and opopanax collection and trade in the livelihood of the pastoral and agro-pastoral poor was conducted in two districts (Chereti and Hargelle) of the Afdher zone, one of the gum potential administrative zones in the region. A transect sampling was used to study the population status, while focused group and key informant discussion and household interview were used to document the role of myrrh and opopanax in the village economy. The analyses of the vegetation data disclosed, the vast arid woodlands of Afdher zone is far rich in diversity and abundance of oleo-gum resin yielding species of the genera Commiphora, Boswellia and Acacia. Among others, C.myrrha and C.guidotti were found to be the predominant components of the study vegetations. The average densities ha -1 of the two species was found to be 107 and 45 trees, respectively. The result of the analyses of population status for C.guidotti showed approximately discontinuous or periodic recruitment, while for C.myrrha it showed reversed J-shape indicating the possibility of sustainable management of the study species for future commercial use. The socio-economic study result showed, oleo-gum resin bearing resources of the Afdher zone play significant role in the economy of rural poor households. The annual cash income generated per household from sale of true myrrh and opopanax ranged from US$175.00 to US$ 610 per season. In economic term, gum and resin collection ranks second after livestock in the overall household income of the study areas, where the share of myrrh and opopanax together was range from 52-72.5% at different study sites. In conclusion, the existing population status of the study species grantee sustainable trade volume collection of true myrrh and opopanax on one hand and if further scaled-up and integrated, the sub-sector even play significant role in food security agenda of the region and the study zone in particular. More importantly, the study also showed the change in attitude of the local community and officials to manage woodlands to produce gum and resins as it is lesser ecologically destructive than other land uses in the area, which of course encourages conservation objectives in drylands of Ethiopia.
... The evaluation of the quantity of fruits produced per tree was performed in December and January corresponding to the period when the fruits are mature enough and start ripening. To do so, the direct counting method has been used, because it is less destructive and more practical (Peters 1996;Lamien et al. 2007). This direct method of single pass counting allowed to obtain a real value of the number of fruit produced per tree since S. spinosa is a shrub of medium height thus facilitating direct counting. ...
Article
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Key Message Strychnos spinosa growth was less responsive than its fruit production, to tree size, protection status and climate; its fruit production increased with tree size, and more so on protected sites. Abstract Abiotic and biotic mechanisms (e.g. climate, human perturbations) are presumed to shape tree growth and reproductive performances. Using the wild fruit tree Strychnos spinosa Lam., as a case study in Benin, we tested whether (and how) tree growth and fruit production were influenced by protection status (non-protected vs. protected sites), climatic zones (Sudanian vs. Sudano-Guinean zones) and size classes (tree diameter < 15 cm; 15–20 cm and > 20 cm). We also tested which climatic variables were important in predicting tree growth/fruit production. Tree growth was only influenced by size class, with higher growth rate in smaller than bigger size classes. Unlike tree growth, fruit production varied significantly with climate and protection status (higher fruit production in Sudano-Guinean than in sudanian zone, and on protected sites than non-protected sites). Fruit production also increased with tree size, and more so on protected sites than non-protected sites. The effect of protection status on fruit production also varied with climatic zones, with protected trees having more fruits than non-protected trees in Sudano-Guinean zone, while both protected and non-protected trees showed similar fruit production in the Sudanian zone. There was a trade-off mechanism between fruit production and growth, which was more pronounced on protected sites. Our study showed that both climate and protection status were considerably important for fruit production, in significant positive (resp. negative) effects of temperature and relative humidity, via mediation by tree size in protected (resp. non-protected) sites. These underlying drivers should be taken into account when predicting scenario for fruit yield under future climate.
... A greater stock of seedlings in the understory and higher density of trees in the central diameter classes are structural features of late secondary species, ecological group according to the Budowski classification (Budowski, 1970). Pentaclethra macroloba would then belong to this group that shows a discontinuity in recruiting individuals over time (Peters, 1996) and depends on large disturbances to establish in the forest canopy. Pentaclethra macroloba seedlings appear to be adapted to the low light of the understory and they persist for a long time suppressed below the forest canopy (up to 11 years in the understory Figure 5), waiting for openings to reach the canopy (Oberbauer & Strain, 1985). ...
Article
Little is known about the life history and environmental factors that regulate the growth rate of hyperdominant trees in flooded Amazonian forests. Pentaclethra macroloba is a hyperdominant tree, and it is widely explored in the Amazon, because its seed oil is a powerful herbal medicine. We evaluated the demographic structure and growth patterns of P. macroloba and tested the effect of the Amazon River flood pulse on its growth. We modeled the growth and determined the age of P. macroloba by analyzing the growth rings of 30 monitored trees in relation to hydroclimatic variables. We also inventoried 240 juvenile and 2072 adult trees arranged in a clustered pattern. The diametric distribution pattern of the juvenile and adult trees was exponential and log-normal, respectively. The trees were found to be up to 102 years old, and 47% of them grew freely toward the canopy. Peak growth in height and diameter occurred at 24 (61.7 cm year-1) and 46 (9.38 mm year-1) years, respectively. Pentaclethra macroloba showed cambial dormancy during the seasonal peak of rainfall (R2 = 0.41; t = −2.62; p < 0.01) and flooding of the Amazon River (R2 = 0.47; t = −3.01; p < 0.01). Increases in rainfall and flood level of the river in the rainy season control the growth rate of P. macroloba, making it a seasonal process. The demographic and growth patterns of P. macroloba respond to the environmental heterogeneity of the estuarine floodplain forest and also reflect its life history over time.
... To determine if these species require management interventions within the park Buffer Zone, further research on harvesting techniques and volumes harvested, as well as on population density and structure, are needed. Slow growing, old-growth forest species that occur in low densities are particularly vulnerable to overharvesting (Peters 1996). Autranella congolensis, for instance, is known to occur mostly at very low densities (Lemmens 2007). ...
Article
From tree species to forest services: ethnic differences in Lomami, Democratic Republic of the Congo. Ethnicity is well–known to affect plant species’ utilization, but how ethnicity affects the identification and importance ranking of forest ecosystem services has been less documented, particularly in the Congo Basin. This research investigates how six different ethnic groups (farmers of Bantu origin and Mbote hunter–gatherers) use and value tree species and forest ecosystem services in Lomami National Park, in central Democratic Republic of the Congo (DRC). Data were collected through 24 focus–group discussions with village elders, four for each ethnic group studied. Considerable variation in preferred tree species was observed: of the 89 morphospecies cited in total only two were cited by all ethnic groups for the same usage. Ethnicity also affected the identification and importance ranking of forest ecosystem services. Mbote hunters–gatherers prioritized bushmeat, honey, and identity, while farmer groups prioritized bushmeat, fish, and microclimate regulation. We discuss the implications of the findings for forest management in the Buffer Zone of the national park.
... The population structures and status of natural regeneration of the entire woody vegetation and that of gum-and resin-bearing woody species was assessed from the frequency distribution of diameters based on histograms constructed by grouping all individuals of each woody species into the following successive diameter classes: 1 = 0 -10, 2 = 10-20, 3 = 20-30, 4 = 30-40 and 5 = 40 cm [17][18][19]. ...
Article
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Diversity, population structures, and regeneration status of gum- and resin-producing woody species, were assessed in 116 sample plots, each measuring 400 m2 and established along line transects. The data were collected in two selected districts, namely, Sherkole and Kurmuk in Benishangul-Gumuz National Regional State, one of the gums and resin belts in western Ethiopia. The gum- and resin-producing woody species had 1.04 and 0.7 diversity and 0.576 and 0.49 evenness values at Kurmuk and Sherkole districts, respectively. They accounted for 26% and 46% of the density, 51% and 58% of the basal area, and 32% and 53% of the Importance Value Index of all the woody species, respectively. The gum- and resin-bearing woody species exhibited three patterns of population structure. The first pattern suggests good reproduction abilities of the species coupled with a good recruitment of seedlings and their subsequent continuous growth to replace older individuals over time, indicating stable regeneration. About 61% of the gum- and resin-bearing woody species fall under this category. The other two patterns indicate the hampered regeneration status of the woody species. Heavy grazing, conversion to cropland by small-scale farming, gold mining, recurrent fire, and climate change were mentioned as major bottlenecks of natural regeneration and recruitment. Policy, extension, and research recommendations are discussed.
... Therefore, by reducing the structural and species diversity of a forest, logging and silvicultural treatments can also produce a number of largely as yet unknown ecological repercussions. These may include reductions in numbers of pollinators, seed dispersers, alterations in plant-herbivore relationships and the possibility that timber exploitation may ultimately produce conditions in which it is difficult for many forest species to regenerate (Peters, 1996). Numerous studies have related forest composition to the size and frequency of disturbances (Veblen, 1989;Whitmore, 1989). ...
Technical Report
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Studies on the knowledge and use of natural resources by local populations may contribute to finding economic alternatives for these populations, especially in terms of the use of plants for treating health problems. In this research, the ethnobotany and ecology of the medicinal plants of the Bia Biosphere ecosystem was studied, in order to identify the plant species used for reproductive healthcare and provide baseline information for future pharmacological and photochemical studies. Furthermore, this research aimed at promoting the conservation of medicinal plants as well as the traditional knowledge associated with them, so that long-term biodiversity values would not be lost.
... Adicionalmente, la presencia de individuos en todas las clases de altura en Cajálbana (Fig. 4A) sugiere que se trata de una población auto-regenerativa acorde al criterio de Peters (1996). Este tipo de población se caracteriza por poseer individuos en todas las etapas de desarrollo con probable mortalidad, los cuales pueden ser reemplazados por los que se encuentran en etapas anteriores (Peters 1996). Las poblaciones caracterizadas por la presencia de individuos en todas las clases y con mayor frecuencia en las clases menores se conocen como poblaciones normales o estables (Large & Braggins 2004). ...
Article
Los estudios de estructura poblacional permiten analizar la variabilidad dentro y entre poblaciones naturales y son esenciales para emitir criterios sobre el estado de conservación de las especies. Phyllanthus orbicularis es una especie endémica de Cuba que habita en matorrales xeromorfos espinosos sobre serpentina, donde es dominante, sin embargo, no se han realizado estudios ecológicos de sus poblaciones. Conocer la estructura poblacional de P. orbicularis podría contribuir a evaluar el estado de conservación de este taxón y el de los matorrales xeromorfos espinosos sobre serpentina. El presente estudio tuvo como objetivo comparar la estructura poblacional de P. orbicularis en cuatro localidades de Cuba, en las que se realizó un muestreo sistemático por 10 parcelas de 4 m2. En cada parcela se registró el número de individuos y se les midió la altura, el diámetro de la base y la cobertura de la copa. La estructura etaria se caracterizó a partir de cinco clases de estado según la altura y el diámetro de la base. Adicionalmente, se calculó la densidad poblacional y el patrón de arreglo espacial resultó agregado. Las cuatro poblaciones se encontraron envejecidas, con un alto porcentaje de individuos adultos respecto a los juveniles. La población mejor estructurada fue la de Cuabales de Cajálbana, ya que presentó individuos en todas las clases de estado delimitadas; y la de peor estado la de Lomas de Galindo, en donde la influencia antrópica ha alterado la población natural de la especie. Además, el número de individuos de Phyllanthus orbicularis por clase de estado es dependiente de la localidad, lo que se evidenció en que la distribución por clases de estado no es la misma en cada una de las poblaciones estudiadas. Esta asociación pudiera estar dada por el nivel de manejo que existe en cada localidad, ya que las medidas de conservación en un área potencian el mejoramiento de las poblaciones de las distintas especies de la región.
... The real necessity of domesticating certain species of NTFPs including Garcinia kola, G. lucida, Monadora myristica, Tetrapleura tetraptera and Ricinodendron heudelotii; is because of their importance in sustaining the livelihood of communities and the scarcity that causes the increase in their prize on markets since they come from far where these NTFPs are over-exploited. Peters (1996) reported that commercial harvesting of NTFPs has a number of negative impacts, including a gradual reduction in the vigor of harvested plants, decreasing rates of seedling establishment of harvested species, potential disruption of local animal populations and nutrient loss from harvested material. Guedje (2002) observed that stripping of the bark of Garcinia lucida, which is used as palm wine additive, resulted in a 74 % mortality rate. ...
... Secondly, the time horizon for monitoring some products can be extremely long. Peters (1996b) suggests intervals of five years between regeneration surveys for some species. In some cases, the impact of harvesting will only be noticeable after even longer periods. ...
... It was constructed by using the density of individuals of each species (Y-axis) categorized into seven diameter classes (X-axis), i.e. class 1 ¼ < 2 cm; class 2 ¼ 2-5 cm; class 3 ¼ 5-7.5 cm; class 4 ¼ 7.5-10 cm; class 5 ¼ 10-15 cm; class 6 ¼ 15-20 cm; class 7 ¼ >20 cm. The purpose of using size class distributions in diameter at breast height (DBH) is to investigate the regeneration status of the woody plant species (Peters and Mundial, 1996). ...
Article
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Exclosures are popularly applied to rehabilitate degraded lands and to gradually restore the productive potential of the land in the long term. This study was conducted to examine the impact of removing human and livestock interference from a degraded land to allow natural recuperation for extended period of years. The aim was to assess the trend of changes in the composition, diversity and structure of the woody component of the vegetation within the exclosures. Degraded lands with different years of exclosure were compared with adjacent open grazing lands under similar environmental conditions. A Systematic transect sampling method was employed to collect vegetation data in sampling quadrat plots, each with a size of 20 m × 20 m, evenly distributed along parallel transect lines. All the woody plant species in each plot were identified and measured for DBH and height. The species diversity and density were analyzed using standard indices. The structural pattern and regeneration status of the woody vegetation was described using size class distribution plots. The findings showed that the woody vegetation composition significantly varied between exclosures and open grazing land. There was significantly (P < 0.05) higher diversity, richness and stand density of the woody species in the exclosures than in the open grazing lands. The size class distribution of the DBH and height of the recorded species exhibited an inverted “J” shape pattern suggesting a healthy regeneration status of the important species, while the distribution pattern in the open grazing lands revealed irregular and less interpretable pattern. This study evidently showed exclosures can successfully contribute to biodiversity restoration in highly degraded lands, perhaps due to improvements in the important micro-climate conditions such as moisture and organic matter.
... According to Peters (1996) frequency class was important to interpret the indication of the regeneration status of the forest. ...
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This study was carried out in Tarmaber district north shewa zone Ethiopia to determine the effect of plantation forest with management intervention on woody plant species diversity, regeneration and soil seed bank species composition in five different forest types, which are adjacent natural forest, managed Cupressus lusitanica , unmanaged C. lusitanica , managed Eucalyptus globules and not managed E. globules plantation forests. A total of 75 circular sample plots of 314 m ² were established along a transect lines. Soil seed bank analysis was done from soil samples collected in each of the plots (225 samples) to examine the similarity between the soil seed bank and aboveground flora. Different diversity index and ANOVA was used in SPSS software for analysis. The result showed that a total of 51 woody plant species was recorded in adjacent natural forest (41), managed C. lusitanica (27), not managed C. lusitanica (9), managed E. globules (22) and not managed E. globules (13) species. Regeneration of seedlings were 3538, 5567, 707, 1462 and 2524 mean stems ha − 1 for natural forest, managed C. lusitanica , not managed C. lusitanica , managed E. globules and not managed E. globules respectively. Unmanaged C. lusitanica plantations had significantly lower densities of mature tree stems ha − 1 as compared to managed C. lusitanica , managed E. globules and adjacent natural forest (F = 14.03, p < 0.05).Similarly in terms of sapling density ha − 1 unmanaged C. lusitanica was significantly lower from other forest types (F = 7.37, p < 0.05). However managed C. lusitanica had significantly higher seedling regeneration (stem density ha − 1 ) than other plantation and adjacent natural forests (F = 16.11, p < 0.05). Generally mean stem densities including tree, sapling and seedling of woody species among different forest types managed C. lusitanica was significantly higher among different forest types (F = 13.01, p < 0.05). From the soil seed bank a total of 22 plant species (20 native and 2 exotic) species were recovered. In different forest types the number of species recorded was in adjacent natural forest (19), managed C. lusitanica (11), unmanaged C. lusitanica (4), managed E. globules (7) and unmanaged E. globules (5). The similarity of the oil seed bank was more or less similar to the above ground flora with maximum Sorenson’s similarity values of 0.633. Generally with appropriate management intervention undergrowth vegetation and soil seed bank status in plantation forest had good species composition and diversity.
... L'estimation de la production fruitière a été réalisée sur 14 arbres sains portant des fruits. Sur chaque arbre,le nombre de fruits a été déterminé en comptant la totalité des fruits collectés sur l'arbre suivant la méthode de Peters(1996) mais modifiée par Kouyaté et al. (2006). La caractérisation morphologique des fruits a été faite à partir de 10 fruitschoisis au hasard parmi la totalité des fruits collectés. ...
... Never the less, uncontrolled extraction due to population increases, high demand for NTFPs and low prices has caused species extinction and forest degradation in many countries [22]. Unsustainable harvesting of NTFPs does have a number of ecological impacts, including a gradual reduction in the vigor of harvested plants, animals, as well as decreasing rates of seedling establishment of harvested species, potential disruption of local animal populations and nutrient loss from harvested material [23].There was ample evidence of over-harvesting even at the time that NTFP exploitation was promoted as nature conservation strategies according to Sunderland et al [24]. There was also an assumption, often implicit [25], that making forests more valuable to local users can encourage forest conservation and poverty reduction [26]. ...
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A study was carried out to assess the contribution of Non-Timber Forest Products (NTFPs) to household food security andincome generation in villages surrounding at study area .Specifically, the study aimed at assessing the common NTFPsutilized by households in the study area, examining socio-economic factors influencing household members accessibilityto NTFPs, evaluating the contribution of NTFPs to household food security and income. structured questionnaire wasadministered for primary data collection. Secondary data of NTFPs collection and crop production were collected fromDistrict Forest Office and District Agricultural Office respectively. Data analyzed by using SPSS software. Descriptiveand inferential statistics were determined. Inferential statics were employed whereas linear regression analysis wasused to determine the socio-economic factors influencing collection of NTFPs and pair t test were used to comparevarious income from NTFPs and other sources Results showed that: there was significant increase of NTFPs collectionin the study aera Results also showed that there was positive relationship between collection of NTFPs and some socio-economic variable including household size, age, education, occupation and duration in years of staying in the area.Non-Timber Forest Products accounted for 100.0% of all respondents in the villages; however they also engaged in otherproduction activities. It also indicates that NTFPs are utilized either directly or indirectly as solution to food insecurityand low incomes among the households. Results further showed that income from selling NTFPs is higher than fromother sources such as selling agricultural produce, selling livestock, business, labour wages and employment in the studyarea. The study recommends that the government should employ more forest officers and provide education on directeconomic importance of NTFPs.
... According to Cunningham (2001), integral counting of the total number of fruits through full harvesting is the easiest method for fruit production estimation. For the implementation of the method, ripe fruits are totally harvested by shaking the tree branches or by using poles (Peters, 1996) or by using binoculars or telescopes of excellent optical quality (Kouyaté et al., 2016). Among authors who used this method there are Ouôba et al. (2006) To account for abiotic factors that may influence fruit production, a pre-counting is often essential at fruit set stage to determine a corrective factor (Kouyaté et al., 2016). ...
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There are several evidences of the prominent roles that non-timber forest products (NTFPs), and particularly wild edible fruit (WEF) play for human food security and poverty alleviation. Although neglected in the past, there are increasing interest on WEF species, and evaluation of their fruit production has become essential. Quantifying the fruit production of WEF species is important to assess their contribution to food security and poverty alleviation but also to plan their sustainable exploitation. In the last three decades, several studies have investigated the productivity of some WEF species. However, the methodological approaches are diverse and there is a need to provide guidelines particularly for early researchers interested by this research field. This chapter provides a methodological synthesis to serve as guidelines for students and researchers for a better assessment of the fruit production of WEF species. The chapter focuses on techniques for sampling, data collection and data analysis. Overall, three main aspects are often investigated across studies. These include (i) potential in fruit production, (ii) effects of abiotic factors such as soil, and climate on fruit production, (iii) relationships between morphological parameters of trees (e.g. diameter and height) and fruit production. Three main methodological approaches are used by researchers: the integral counting of fruits, the collection and counting of fruits fallen under the tree, and the estimation by extrapolation. Each of these approaches was presented and illustrated through a case study.
... According to Cunningham (2001), integral counting of the total number of fruits through full harvesting is the easiest method for fruit production estimation. For the implementation of the method, ripe fruits are totally harvested by shaking the tree branches or by using poles (Peters, 1996) or by using binoculars or telescopes of excellent optical quality (Kouyaté et al., 2016). Among authors who used this method there are Ouôba et al. (2006) on Detarium microcarpum Guill. ...
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Non-Timber Forest Products (NTFPs) designate goods of biological origin other than timber from natural, modi ed or managed forested landscapes. A number of short cycle and cultivated species contributing to food security that remain traditional tend to get less research attention, training and extension. Such plant resources are termed Orphan Crops (OCs), also referred to as minor crops. Due to the increased demands, harvest/ collection of minor crops has tremendously escalated threat of biodiversity loss. Besides, the increased market value of minor crops and their importance in improving livelihood of people in the rural areas raises the need of sustainable management of those crops, which entails e orts toward domestication, selection and improvement. This chapter presents the methods and principles for the genetic improvement of Non- Timber Forest Products & Orphan Crops. It established a 7 steps general roadmap for breeding minor crops. The exercise begins with appropriate goals setting, then germplasm is gathered through collection missions, followed by their morphological and molecular characterization, to provide basic information of lines and guide choice of parental lines. It is very common to encounter narrow genetic base in minor crops. This is dealt with by creating new variants through massive hybridization and more speedily, using mutagenesis. Hybridization has got many designs that serve various purposes, also selection methods are diverse. In case of low inherited traits, the detection of Quantitative Trait Loci (QTL) that set prospects for marker-assisted selection (MAS) has been emphasized. Also, newer breeding tools such as genome-wide association studies (GWAS) and genomic selections (GS) have been discussed. Keywords: Hybridization, Genetic improvement, Marker-assisted selection, Mutation, Orphan Crops
... The exploitation of medicinal plant populations in wild without observing the mode of sustainable use is one of the threats to biodiversity (Schippmann, 1997, Schippmann et al. 2002. The information on natural resources and their spatial distribution is essential to protect rare medicinal species (Peters, 1996;On et al., 2001;Ghimire et al., 2005;Russell-Smith et al., 2006;Gaikwada et al., 2011;Rokaya et al., 2012). ...
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Rhaponticun carthamoides (Willd.) Iljin is a rare medicinal plant listed in the Red List of the Russian Federation. Spatial patterns of its reserves were studied for the monitoring and protection of wild populations at the Kuznetsk Alatau. The dependence of population abundance on environmental factors was revealed by geobotanical profiles. We derived the equation of nonlinear regression for rapid method of determining the weight of subsurface parts by counting the number of shoots. To assess rapidly and monitor the natural reserves we developed a mathematical model describing the abundance of R. carthamoides and its habitat altitude.
... According to Cunningham (2001), integral counting of the total number of fruits through full harvesting is the easiest method for fruit production estimation. For the implementation of the method, ripe fruits are totally harvested by shaking the tree branches or by using poles (Peters, 1996) or by using binoculars or telescopes of excellent optical quality (Kouyaté et al., 2016). Among authors who used this method there are Ouôba et al. (2006) on Detarium microcarpum Guill. ...
... According to Cunningham (2001), integral counting of the total number of fruits through full harvesting is the easiest method for fruit production estimation. For the implementation of the method, ripe fruits are totally harvested by shaking the tree branches or by using poles (Peters, 1996) or by using binoculars or telescopes of excellent optical quality (Kouyaté et al., 2016). Among authors who used this method there are Ouôba et al. (2006) on Detarium microcarpum Guill. ...
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Research on Non-Timber Forest Products (NTFPs) in West Africa has made considerable progress. This provides a collection of hug number of scientific evidences that can be pooled in the form of book for the characterization and monitoring of changes in NTFPs. Numerous observations point out the difficulties in efficiently pooling data in view of their disparity due to various attempts to contextualize methods. To solve this problem, this book is initiated to provide the approaches and methods for monitoring, assessment and conservation of NTFPs. The purpose of this book is to serve as a practical guide to sampling methods, data collection and analysis techniques of NTFPs. This book meets the imperatives of quest for performance and excellence imposed by the dynamics of science. It outlines different sampling approaches for NTFPs inventories and also presents appropriate statistical tools and methods for processing different types of data. Undoubtedly, this book meets a need for scientific information from researchers and students on NTFPs. The book is a guide which remains open to innovations and scientific progress that could enrich possible news editions. This book will be very useful for the scientific community with interest in the sciences of NTFPs.
... Relative density of individuals of each species (y-axis) was categorised into seven diameter classes (x-axis) following Peters (1996), i.e. A = 1-5 cm, B = 6-10 cm, C = 11-15 cm, D = 16-20 cm, E = 21-25 cm, F = 26-30 cm, and G = 31-35 cm. ...
... Plants harvested in tropical forests in Africa have a range of uses from food to medicine to manufacture of household utensils (Peters and Mundial 1996). Non-timber forest products (NTFPs) embody all biological matter of wild plants and animals other than timber extracted from forests and woodlands, including, e.g., fruits, nuts, vegetables, game, medicinal plants, resins, bark, fibers, palms, grasses, as well as small wood products and firewood, among others. ...
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Non-timber forest products (NTFPs) from natural forests in sub-Saharan Africa provide significant benefits to rural communities. In this study conducted on the foothills of Mt. Kilimanjaro, Tanzania, we assumed that the extraction of NTFPs by local communities is related to sex, income, age, household size, and distance from the forest. We interviewed 313 household heads from six villages. We employed a logistic regression with a logit link to test the significance among the variables. Younger females of larger households with lower income and less cultivated land cut fodder and collected firewood more frequently than other villagers. Firewood collection frequency decreased with increasing distance from village to forest whereas fodder collection frequency increased. Men collected medicinal plants more frequently than younger women and if the distance from the village was greater. For firewood and fodder extraction, inter-village variation was greater than intra-village variation, suggesting that differences in access to infrastructure and alternative fodder sites also strongly determined NTFP extraction. Our results contribute to a better targeted participatory forest management.
... Relative density of individuals of each species (y-axis) was categorised into seven diameter classes (x-axis) following Peters (1996), i.e. A = 1-5 cm, B = 6-10 cm, C = 11-15 cm, D = 16-20 cm, E = 21-25 cm, F = 26-30 cm, and G = 31-35 cm. ...
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The present study assessed the population structure, regeneration status and conservation of threatened tree ferns Cyathea, namely, C. brunoniana, C. gigantea and C. henryi in Seijosha forest, Arunachal Pradesh, northeast , India. Individuals of C. henryi had a maximum density of 45 individuals ha-1 while C. brunoniana and C. gigantea had a maximum of 35 individuals ha-1. The population structure showed four general class distribution patterns (i.e. reverse J-shape, Bell shape, iirregular shape, and J-shape). Only C. brunoniana and C. henryi showed reverse J-shaped pattern at two sites, which indicated a stable population. The regeneration status for C. gigantea was poor at most of the sites. There were fewer individuals of young, immature and adult plants of Cyathea, and some species showed poor or no regeneration at certain sites. The conservation status of young/immature/adult individuals was occasional and infrequent. The study revealed many factors threatening Cyathea and suggested some corrective measures which can be helpful for its conservation.
... The important value index (IVI) of each woody species was determined by summation of its relative values of density, frequency and dominance (Kent and Coker, 1992). The population structure of B. papyrifera was also depicted through histogram, constructed by using its density (Y-axis) and diameter classes (X-axis) (Peters, 1996). ...
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Boswellia papyrifera woodland provides considerable economic, ecological and socio-cultural benefits in the drylands of Ethiopia. However, its populations are in rapid decline due to human pressure and environmental degradation. As a consequence, the species is now considered being endangered, demanding an urgent conservation intervention to sustain its existence. This study was carried out in the Abergele district, northern Ethiopia, with objectives to characterize the current population structure of B. papyrifera and prioritize its potential conservation intervention alternatives using Analytical Hierarchy Process (AHP) modelling techniques. The woody species related data were collected from 33 sample plots randomly established in the study area. Data related to the potential intervention alternatives and their evaluating criteria were collected from experts, personal experiences and intensive literature reviews, and then validated using stakeholders’ focus group discussion. Four candidate alternatives were then considered for the AHP: 1) free grazing with no tapping resting period (FGNTR), 2) free grazing with a rotational tapping (FGRT), 3) area exclosure with medium tapping resting period (AEMTR), and 4) area exclosure with long tapping resting period (AELTR). The results showed that the population structure of B. papyrifera is unstable and is characterized by low density (266 trees ha−1), absence of regeneration and saplings (DBH
... The important value index (IVI) of each woody species was determined by summation of its relative values of density, frequency and dominance (Kent and Coker, 1992). The population structure of B. papyrifera was also depicted through histogram, constructed by using its density (Y-axis) and diameter classes (X-axis) (Peters, 1996). ...
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Boswellia papyrifera woodland provides considerable economic, ecological and socio-cultural benefits in the drylands of Ethiopia. However, its populations are in rapid decline due to human pressure and environmental degradation. As a consequence, the species is now considered being endangered, demanding an urgent conservation intervention to sustain its existence. This study was carried out in the Abergele district, northern Ethiopia, with objectives to characterize the current population structure of B. papyrifera and prioritize its potential conservation intervention alternatives using Analytical Hierarchy Process (AHP) modelling techniques. The woody species related data were collected from 33 sample plots randomly established in the study area. Data related to the potential intervention alternatives and their evaluating criteria were collected from experts, personal experiences and intensive literature reviews, and then validated using stakeholders’ focus group discussion. Four candidate alternatives were then considered for the AHP: 1) free grazing with no tapping resting period (FGNTR), 2) free grazing with a rotational tapping (FGRT), 3) area exclosure with medium tapping resting period (AEMTR), and 4) area exclosure with long tapping resting period (AELTR). The results showed that the population structure of B. papyrifera is unstable and is characterized by low density (266 trees ha�1 ), absence of regeneration and saplings (DBH<10 cm) due to different interrelated disturbances such as overgrazing, over tapping, pests, agricultural expansion and poor managements. The overall priority ranking value of all stakeholders using the AHP techniques also indicated that AEMTR (with overall rank value of 0.352) and AELTR (0.294) as the best alternatives strategies, respectively, for sustainable B. papyrifera woodland conservation. For the success of these strategies, their economic impacts at their early implementation stages (5–10 years) should be minimized by collecting different non-timber forest products from the woodland. Continuous capacity building training on sustainable utilizations and managements of B. papyrifera woodland should also be provided for all relevant stakeholders.
... These products may be used for subsistence or for sale, providing cash income. There is growing awareness that sustainable forest management should include measures for the effective conservation and management of NTFP resources in order to meet the actual and future needs of local people [7]. Proponents of the 'NTFP-strategy' pointed to important benefits of NTFP exploitation for local communities, such as goods (food, fodder, fuel, medicine, construction material and small wood for tools and handicrafts), income and employment. ...
Article
The present study was conducted in the tribal area of Goregaon cluster of Gondia district of Maharashtra. Livelihood systems in these districts are complex, primarily dependent on agriculture (including allied activities-livestock, poultry, fishery, etc.) forest, agricultural labour and village artisans. It is more important that the problems of the people of disadvantaged regions like rainfed, hilly and tribal areas be addressed through imparting new skills to the poor and building up durable income generating assets and capacity to adapt to rapidly changing markets. The said district have been so chosen because of poor indices in various areas of development including, amongst others, infrastructure, agriculture, food availability, nutritional health and sanitation and last but not the least economics of the habitants. Study suggested alternate sources of income to the villagers to improve their socioeconomic conditions as well as increasing the income level and employment opportunities by effective collection and marketing of non-timber forest product and the same time making villagers come forward for forest protection.
... Species composition and size class show the likely state of the vegetation of a site (Enright, 1982). The purpose of using size class distributions in DBH is used to investigate the regeneration status of the woody plant species (Peters, 1996). ...
Article
The findings of the first four Aloidendron dichotomum population surveys in 2015 that form part of a long-term monitoring initiative started by the South African Environmental Observation Network at Meerkat National Park were compared with the findings of a second survey in the same populations in 2021. Aloidendron dichotomum is a keystone species and was previously suggested as a climate change indicator species therefore understanding its population dynamics is important. A general population density and mortality survey, as well as a detailed demographic survey were repeated in August 2021 using the same methods that were used in 2015. The surveys were conducted in the same populations but not of exactly the same individuals. The aim of this study was to compare the findings of the 2021 surveys with the findings of the 2015 surveys in order to assess whether it is crucial to survey exactly the same individuals within a population or not. Live: dead ratios varied considerably across the populations between the surveys conducted in 2015 (range: 17 to 35 per ha) and in 2021 (range: 6 to 28 per ha). For each population the size class distribution (SCD) types did not differ significantly between 2015 and 2021. Populations had zero permutation indices for basal diameter for the two surveyed years suggesting that the populations are monotonically declining and therefore the populations are stable. However, two permutation indices for height were not zero. The presence of leaf fungi and scale during the two surveys was generally low while the presence of lichen remained similar between survey years. There was more damage to leaves and stems in 2021. Our conclusion is that the general demographic findings for the 2015 and 2021 surveys were similar so it is not necessary to survey exactly the same individuals within a population to determine the general demography of a population. However, marking and measuring exactly the same individuals could provide valuable insights onto the finer nuances of population demographics and dynamics in this species.
Article
en The recently created Lomami National Park has an extensive Buffer Zone where local communities are allowed to use forest products sustainably. However, the management of this Buffer Zone is hampered by inadequate understanding of the floristic composition and the impacts of harvesting certain plant products. To fill in this data gap, we established and sampled 30 vegetation plots of 40 × 40 m, and investigated the population structure of 11 useful tree species preferred by local communities. We found that the Buffer Zone is mostly composed of mixed-species undisturbed old growth forest. It contains nine tree species of international conservation concern (listed in the IUCN Red list and/or apart from the Red list, Gibourtia demeusei, not been assessed by IUCN Red list, is listed in CITES Appendix II since January 2017; UNEP-WCMC, Review of selected Dalbergia species and Guibourtia demeusei, UNEP-WCMC, 2017). The floristic diversity of the Buffer Zone, which requires further investigation as some species remained unidentified. Most preferred tree species (including Garcinia kola and Milicia excelsa) are abundant and showed a reverse-J size distribution, indicating a relatively stable population structure. For these species, current levels of exploitation seem sustainable. Further research is needed for two nonabundant species of conservation concern (Autranella congolensis and Michelsonia microphylla). Although timber/firewood commercial harvesting is currently limited in the study area, the management plan of the Buffer Zone should consider these risks given increasing commercial hunting. Surveys and permanent plots provide essential information to guide the management of newly formed protected areas. Résumé fr Le parc national de Lomami récemment créé possède une vaste zone tampon où les communautés locales sont autorisées à utiliser les produits forestiers de manière durable. Cependant, la gestion de cette zone tampon est entravée par une mauvaise compréhension de la composition floristique et des impacts de la collecte de certains produits végétaux. Pour combler ce manque de données, on a établi 30 parcelles de végétation de 40 x 40 m et échantillonné les arbres de diamètre ≥10cm. On a étudié la structure de la population de onze espèces d’arbres utiles et préférées par les communautés locales. cette étude a démontré que la zone tampon est principalement composée de forêts anciennes non perturbées d’espèces mixtes. Dans cette zone, on a identifié neuf espèces d’arbres dont la conservation est préoccupante au niveau international (inscrites sur la liste rouge de l’UICN et/ou l’annexe CITES). La diversité floristique de la zone tampon nécessite une étude plus approfondie car certaines espèces sont restées non identifiées. La diversité floristique est vraisemblablement plus importante que la zone centrale, majoritairement formée de peuplements monodominants. Les espèces d’arbres préférées (y compris Garcinia kola et Milicia excelsa) sont abondantes et présentent une distribution de taille en J inversé, indiquant une structure de population relativement stable. Pour ces espèces, les niveaux actuels d’exploitation semblent durables. Des recherches supplémentaires sont nécessaires pour deux espèces non abondantes dont la conservation est préoccupante (Autranella congolensis et Michelsonia microphylla). Bien que la collecte commerciale de bois d’œuvre/bois de chauffage soit actuellement limitée dans la zone d’étude, le plan de gestion de la zone tampon devrait tenir compte de ces risques compte tenu de l’augmentation de la chasse commerciale. Les placettes permanentes fournissent des informations essentielles pour guider la gestion des aires protégées nouvellement constituées.
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The aim of this study was to analyse the species composition, structures, and regeneration of woody plant species and the impacts of site factors on the natural regeneration of tree species in four study sites of MFBR. The vegetation data were collected systematically in 140 plots with the size of 400 m2 for trees; 25 m2 for seedlings, saplings, shrubs, and lianas; and 1 m2 for herbs. Individual tree and shrub DBH ≥ 5 cm were measured and counted. The diameter at breast height (DBH), frequency, basal area, importance value index (IVI), and density were used for vegetation structure description and regeneration. A total of 158 plant species belonging to 115 genera, 56 families, and 80 species (51%) trees, 26 (16%) shrubs, 19 (12%) herbs, and 33 (21%) lianas were identified and recorded. The most dominant families were Euphorbiaceae, Rubiaceae, and Moraceae, each represented by 13 species (7.4%), 12 species (6.8%), and 10 species (5.7%), respectively. The tree densities varied from 1232 to 1478 stem ha−1, sapling density 176.8 to 708.7 stem ha−1, and seedling density 534.7 to 1657.5 stem ha−1, with an average basal area of 63.6 m2 in the study sites. Dracaena afromontana was the most frequent woody species in the MFBR occurring in 90% followed by Celtis zenkeri (65%) and Pouteria altissima (62.5%). The regeneration status of all the woody plant species was categorised as “not regenerate” (9.6%), “poor” (30.7%), “fair” (59.5%), and “good” (10.8%) in all sites. The correlation result between natural regeneration and site factors revealed both positive and negative relationships. However, the main threat to the biosphere reserve is illegal logging for different purposes. Therefore, awareness creation on sustainable forest management, utilisation, conservation of priority species, and livelihood diversification to the local community and encouraging community and private woodlot plantation in the transitional zone of biosphere reserves are recommended.
Chapter
Describing vegetation types is critical for managing natural resources and assessing ecosystem risk. Vegetation maps are historically produced by “Western experts,” often ignoring local-level groups critical to resource management. Indigenous hunters, as resource managers, have strong connections to their landscapes and their descriptions of vegetation within their homelands can be useful in the map-making process. This project examined the usefulness of vegetation descriptions from Rupununi, Southern Guyana Indigenous hunters in the map-making process and how their descriptions were influenced by biophysical environmental attributes. A Landsat TM and ASTER DEM merged imagery of the Rupununi was classified using Indigenous hunters' vegetation descriptions to train the classification and assess accuracy. Based on the hunters' vegetation descriptions an eleven-class map was produced that covered the main vegetation types they described. Whereas “expert” maps rely on organized forest inventory data, Indigenous hunters' vegetation classifications were influenced by their interactions with the biophysical environment. The final map shows that Indigenous hunters may be important partners in the map-making process and play key roles in tropical forest management decision-making processes.
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Apesar de seu potencial na região amazônica, sistemas agroflorestais têm sido estudados principalmente entre grupos indígenas, que são culturalmente afastados da maioria da população atual em zonas rurais. Este estudo descreve um sistema agroflorestal utilizado por uma família de cultura Luso-brasileira. O sistema foi desenvolvido na mata de várzea do estuário amazônico, sujeita a inundações periódicas e prolongadas que dificultam as práticas convencionais de agricultura. Três zonas de maneio na vizinhança da casa são descritas detalhadamente: quintal, floresta manejada, e mata. Juntas essas zonas apoiam ou possibilitam uma grande variedade de atividades, tais como caça; pesca; criação de animais domésticos; e utilização de frutos, palmito, madeira, adubo, plantas ornamentais, fibras, látex, mel, sementes oleaginosas, remédios, utensílios, etc. Além de produtos de subsistência, essas atividades fornecem muitos produtos de mercado que são comercializados em Belém, possibilitando a compra de materiais agrícolas de primeira necessidade. Entre a família estudada, o sistema agroflorestal permitiu a substituição da agricultura convencional pela colheita de produtos silvestres. Sob certas condições, essa estratégia poderia ser uma alternativa viável de uso de terra no estuário amazônico.
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The Otomi village of San Pablito in northern Puebla has preserved the tradition of making bark paper for over 400 yr, and today is the only papermaking center in all of Mexico. In the past 20 yr, bark paper has become highly commercialized and severalaspects of the Otomi papermaking process have changed. Unprecedented production levels have caused the total depletion of traditional sources of raw material. In response to this situation, the Otomi have been forced to change the types of bark that are utilized, the logistics of bark collection, and the treatment of the bark fiber prior to use. The majority of the paper currently produced in San Pablito is made from the bark ofTrema micrantha imported from the state of Veracruz. A plantation of this species is being established near San Pablito to reduce the Otomi dependence on outside sources of raw material.
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An inventory was made of 50 ha of primary lowland rain forest in Peninsular Malaysia, in which ca. 340,000 trees 1 cm dbh or larger were measured and identified to species. Out of a total plot tree flora of 820 species, 76 species are known to bear edible fruit. Especially diverse were the wild species of mango (Mangifera, Anacardiaceae, 12 spp.), mangosteen (Garcinia, Clusiaceae, 13 spp.), breadfruit (Artocarpus, Moraceae, 10 spp.) and rambutan (Nephelium, Sapindaceae, 5 spp.). Median population size for all species of fruit trees was 3.0 trees per ha and 0.2 adult trees per ha. Direct economic value of wild fruit trees was small; only one species has been very much collected and sold, Parkia speciosa (Fabaceae), amounting to less than US 20 per ha per year. The potential value of the species as genetic resources is very large: 24 species are cultivated, 38 edible species are congeneric with cultivated crops and at least 10 other species bear inedible fruit but are related to cultivated crops. We conclude that the Peninsular Malaysian rain forest is exceedingly rich in wild fruit trees, that these normally live at low densities, and that their principal economic value is as genetic resources. < /div > < div class=bstract < a name=bs2 < /a > de tierra baja primaria de selva lluviosa de Malasia Peninsular, en el cual se medió y se identificó la especie de aproximadamente unos 340,000 árboles de 1 cm de diametro (a la altura del pecho) o mayores. De un total de un terreno de flora de árboles de 820 especies, se sabe que 76 especies dan frutos comestibles. Resultaron ser particularmente variades las especies silvestres de mango ( < i > Mangifera < /i > , Anacardiaceae, 12 spp.),
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This article comes from a paper presented at the UNESCO-IVIC International Workshop on rain forest regeneration and management held in November, 1986 in Venezuela. It reviews FAO and other studies which indicate that protective management of many humid lowland forests is both technically feasible and economically viable. Considers natural forest management - ie controlled and regulated harvesting - combined with silvicultural and protective measures to sustain or increase the commercial value of subsequent areas all relying on natural regeneration of native species. Includes studies of Malaysia, Philippines, Brazil, Peru, Colombia, Ecuador, Suriname, Costa Rica and French Guiana; looks at forest harvesting in Africa; problems and opportunities in implementing a natural system of forest management. Concludes that in a model management programme negative ecological impacts of harvesting or alternative land use can be minimized. -from Author
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Convolvulaceous climbers in the genera Merremia and Operculina are troublesome weeds in young plantations in the Solomon Islands. The climbers require full sunlight to grow vigorously. Silvicultural practice can be varied to control light availability and hence control the climbers.-from Author
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Six months after logging, the site was almost covered by regrowth dominated by small fast growing secondary trees. The regrowth comprised 51 genera with 60 species and a total density of 4/m2. The total seed bank density was 4100/m2 and the density for the seed rain was 2782/m2 both of which were dominated by secondary trees and weeds. Older regrowth sites ageing from 1-10 yr have lower species diversities and densities. -from Author
Article
Each established silvicultural system for tropical forests reflects its time and place of origin. There is much to be learned from these systems, but it is dangerous to apply them without modification to forests about which little is known. Instead, it is preferable to begin by testing the forest's reactions to individual silvicultural operations and to simple improvement treatments. This approach will rapidly provide reliable information upon which to develop a suitable silvicultural system. -Author
Article
The Amazon region is characterized by its physiognomy which is represented by the picture of a huge, dense forest. Its limits are well defined by the size of the vegetation as forest or non-forest.
Article
A new dendrometer has been developed for monitoring radial dimensional change of trees in tropical environments. The sensing unit of this instrument consists of a rectilinear potentiometer in a moisture- and corrosion-resistant housing. The sensor is powered by a mercury battery through simple circuitry. Sensor output can be read with a voltmeter or recorded on a variety of instruments.
Article
This paper gives an account of observations carried out on five plant species in the rain forest of Veracruz, Mexico, and indicates that non-hovering birds such as vireos, warblers, tanagers, finches, orioles, blackbirds, and honeycreepers are important as flower visitors and should be investigated in the future as pollinators of American rain forest plants.
Article
In a glass-house at Cambridge, under conditions of temperature, humidity, shading, insolation and daylength comparable with those in a clearing in West African Rain forest, young plants of the rapidly growing tree of tropical regrowth vegetation, Trema guineensis (Schum. & Thonn.) Ficalho, give an estimated mean unit leaf-rate (net assimilation rate) of 14 to 15 g/m^2/week, while Helianthus annuus gives 33 to 34 g/m^2/week. The rapid growth of Trema cannot be explained by a high rate of dry weight increase per unit leaf-area, but may lie in its prolonged and efficient development of new leaf-area. A review of the literature suggests that many (but not all) woody plants, both temperate and tropical, show lower unit leaf-rates than herbs under similar conditions.
Article
Nested quadrats were used to determine natural clump sizes for three understory species in a mature, wet, tropical forest in Costa Rica. Under a closed canopy, individuals > 60 cm tall of the understory palm Cryosophila guagara are shown to clump maximally at a size which corresponds to the size of lightgaps created by fallen canopy trees, suggeting that the distribution pattern of this palm is related to the pattern of fallen trees. Two other understory species, Neonicholsonia watsonii and Carludovica palmata, clump maximally at sizes which do not correspond to the sizes of average canopy gaps.
Article
In a glass-house at Cambridge under conditions comparable to those in a West African Rain forest clearing, 9-month-old plants of the rapidly growing tree Musanga cecropioides R.Br. give an estimated mean unit leaf-rate (net assimilation rate) of 6 g/m2/week at a leaf-area index of 4.0 and 10/g/m2/week at a leaf-area index of 1.0, while Helianthus annuus gives 43 g/m2/week. At the higher leaf-area index, the estimated annual production (including roots) of dry matter is 12 000 kg/ha/year, and the corresponding values are 5000 kg/ha/year and 0.35%. The rapid growth of Musanga does not lie in particularly efficient dry-weight production or energy conversion, but in its capacity for unrestricted internode elongation and leaf production, in its economical branching pattern, and in the continuously favourable humid tropical environment.
Article
1. The coefficient Cmax - C is not a Euclidean measure of distance. Its scale of measure varies relative to inter-stand distance, D, depending on the species composition of the stands compared, and tends to overestimate D in species-poor communities and underestimate it in species-rich types. Cmax - C should not therefore be used as a substitute for D. 2. Oblique axes when plotted as perpendicular distort the relationships of the stands. This inadequacy is overcome by perpendicular axis construction as described by Orloci (1966). 3. The use of extreme stands as reference points for the axes results in a loss of ordination efficiency. This inadequacy is corrected in the principal component analysis of an appropriate similarity coefficient. 4. A comparison of the three ordinations suggests that the Bray & Curtis ordination exaggerates the appearance of a continuum. 5. The success of simple ordinations is dependent on the position of extreme stands relative to the point cluster. A better method is principal component analysis of an appropriate similarity coefficient.
Article
The very large number of potentially economic species in the rain forests of south east Asia is emphasized by describing various categories of usage. The forests are increasingly intensively utilized for timber, wood products and cellulose, and there are biological and sociological dangers in totally harvesting the above-ground bio- mass. Numerous species have the combination of features required for growth in plantations, at present foresters utilise very few. There is an assured future for rattans especially if attempts at silviculture succeed. Traditional societies utilize innumerable plants for ornamentals, fruits or seeds of which very few enter commerce, and those which do have wild relatives awaiting exploitation for superior characteristics. Forests are not today intensively exploited for phytochemicals (cellulose, lignin, hemicellulose, protein, insecticides, essential oils, food colourings, drugs, medicines, gums, latexes, resins and waxes) but major developments can be expected as the world's oil reserves run out and today's strategy must be to keep mankind's options open by maintaining diversity.
Article
Life table data for A. cunninghamii and A. hunsteinii from a total of four sites near Bulolo, Papua New Guinea are presented. Sample populations are analysed using the Leslie matrix method. Values of λ, the ‘finite rate of natural increase’, vary between sites and species in the predicted manner. The value of λ calculated for the A. cunninghamii population is close to, and slightly above 1.0, while the three values calculated for A. hunsteinii show wide variation, with values both above and below 1.0. It is argued that A. hunsteinii is a gap regenerating species and cannot regenerate beneath a closed canopy. Evidence presented here and elsewhere indicates that A. cunninghamii is more shade tolerant and therefore, theoretically, better adapted to stable forest situations.
Article
Productive natural tropical high forests are diminishing at a very rapid rate, yet the establishment of forest plantations cannot cope with the shortfall in timber resources arising from the continued destruction of high forests. Since most of the valuable tropical timber species thrive best under natural conditions, it is worthwhile to seek appropriate means of improving the productivity of the natural high forest. Natural regeneration techniques have been hampered by inadequate understanding of factors governing species distribution, ecological succession (particularly after extensive and intensive forest disturbance), and by incomplete utilization of the wide range of species and wood products available.Recent research studies in Nigeria and South East Asia have shown that total standing crop in the tropical high forest can be as much as 240 m3/ha if all woody species above 10 cm dbh are enumerated. Although about 65% of this volume may be accounted for by lower- and middle-storey species which are not normally extracted in routine timber exploitation, it represents an untapped reservoir of cellulose which can sustain well-planned integrated wood-based industries. With better knowledge of tropical ecology and silviculture, and given such vast yield potential of wood, and the wide variety of non-wood benefits, the author suggests a re-evaluation of the policy favouring the indiscriminate establishment of plantations of inferior, and allegedly high-yielding, species to replace rich tropical high forests.
Article
The Nigerian tropical shelterwood system (T.S.S.) was a major management preoccupation of the Forestry Service in western and mid-western Nigeria during the 1950s, and altogether about 200 000 hectares of forest were treated under this system. The method was developed in response to what, at the time, was regarded as a need for an extensive system of regeneration which could keep up with, and be financed from, the earnings from forest exploitation. It was intended to obtain sustained or improved yields, particularly of the primary economic species, to supply mainly export markets. The system consisted of canopy opening, by poisoning unsaleable trees with sodium arsenite to promote survival and growth of seedlings of valuable species, and also climber cuttings and cleanings in order to control climbers and herbaceous weeds. The treatments were begun 5 years before exploitation. Originally the felling cycle was fixed at 100 years, and a final crop of 25 fully grown trees per hectare was regarded as acceptable, compared with actual removals at the time of about 5 trees per hectare on average. Satisfactory regeneration was regarded as a minimum of 100 well grown seedlings and saplings of listed economic species per hectare.
Article
This paper describes a field trial of two rapid-survey methods of classifying vegetation for conservation purposes. The work was carried out by staff and students of the Conservation Course at University College, London, on Majorca in the spring of 1971. A brief review of the two methods is followed by an account of the difficulties encountered with their use in the field and of their theoretical advantages and disadvantages. It was concluded that both methods offer a quick, repeatable approach to vegetation classification which requires little previous knowledge. Fosberg's method was considered the more logical because Ellenberg's includes habitat data which may lead to circularity of argument. Ellenberg's was found to be the easier to use in the field, but this is possibly because it has been principally developed in temperate regions. Both methods offer a very useful framework for an ecological inventory of an area but are subject to practical difficulties when the vegetation has to be mapped.
Article
This article is based on "Our Common Future" reported by the World Commission on Environment and Development. Discussed are the conditions making development sustainable including reviving growth, equity, meeting needs and aspirations, population, productivity, economic and ecological systems, budgets, and military expenditures. Lists seven references for further reading. (YP)
Article
A fungus known asCytosphaera mangiferae Died, was isolated for the first time from the diseased tissues of standing trees ofAquilaria agallocha Roxb. Irregular patches of diseased wood, a result of natural infection, are found in the trunks of standingA. agallocha trees, which are of great economic importance. A fragrant perfume locally known as ‘attar’ is obtained from the diseased wood by steam distillation. Incomplete or partially diseased wood is employed in the preparation of a joss-stick locally known as ‘agarbatee,’ which gives out fragrant fumes on burning. The fungus colonised wood blocks of A agallocha when these were inoculated artificially. There is a possibility of commercial exploitation for the production of diseased wood by artificial infection.
Article
Nypa fruticans Wurmb. dominated wetlands are commonly found where brackish waters overflow with the tides. This swamp palm is harvested for a variety of purposes, including roofing, construction materials and peels for rolling cigarettes from its leaves, and sugar syrup, an intoxicating juice, vinegar and alcohol from its floral and fruit stalk exudate. Extraction techniques are traditional, and current resource development strategies are non-existent in areas where nipa palms are being harvested. Maintenance of adequate supplies of the resource requires knowledge of demand on the resource and its renewability under natural and harvest regimes. To sustain production, indigenous populations follow conservation-oriented practices in husbanding the natural resource.
Article
Minor forest products such as rattan and Manila copal have long been an important source of cash income for indigenous forest collectors in Southeast Asia. Focusing on the Tagbanua of Palawan Island in the Philippines, the history and economic significance of forest collecting in the region are described. The paper also documents the growing scarcity of forest products in Palawan and discusses several policy options intended to help preserve rattan and copal resources.
Article
The role rattan plays in the life of a small Semai community in West Malaysia is discussed. Of the 24 rattan species occurring in the study area, four are frequently used for binding, housebuilding, basketry, fish traps and snares, and other artifacts. These are briefly described and some illustrated. Some species are used for food, medicinal, and ritual purposes. The Semai have a profound knowledge of nature and have a good concept of rattan systematics that comes very close to scientific classification. Demand for rattan for commercial use threatens the rattan populations and has led to heavy depletion of some of the most useful species.
Article
Forest-product use among nonforest dwelling cultural groups in Southeast Asia is not well known, particularly in contrast to what is known about indigenous forest-product collectors. A case study in one lowland Filipino village in Leyte, Philippines, revealed that over half of village households depend upon 8 species of commercially valuable rattan and 8 species of timber as a primary source of livelihood, and that all village households collected forest-products for supplementary and emergency income. The future of the rattan and timber trade on Leyte is seriously threatened by agricultural encroachment and intensive collecting pressures in the absence of forest management.
Article
At Iquitos in the Peruvian Amazon, a plywood industry based on exploitation of Ceiba pentandra developed over the last 15 years. By 1975, five Iquitos lumber mills had been set up to convert Ceiba trees to plywood. The cores of the peeled logs were used for local construction and cabinetry, forming an important secondary industry. By 1983, uncontrolled exploitation had led to total depletion of the resource base and collapse of the Iquitos plywood industry.