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Introduction. Silvopastoral systems play an important role in livestock production, provide benefits to the animal and edaphic components, and offer environmental services such as atmospheric carbon sequestration in the soil and biomass. Objective. To evaluate the capacity of atmospheric carbon sequestration in three systems of different complexities focused on livestock production, in northern Colombia. Materials and methods. The study was carried out at the Turipana Research Center of the Corporacion Colombiana de Investigacion Agropecuaria between 2019 and 2021. The dasometric parameters of the tree/shrub component were evaluated. The aboveground (CBA) and belowground (CBR) biomass of these species were estimated with allometric models. The fallen litter biomass (CLIT) and soil organic carbon up to 30 cm, with readings every 10 cm, were quantified by the combustion method and total accumulated carbon. The design corresponded to complete randomized blocks, with three treatments and four repetitions. The treatments corresponded to two silvopastoral systems (SSP) of different complexity and a grass without trees (Pr). Results. Aerial biomass was higher in the SSP (2.18 ± 1.13, 4.51 ± 3.76 t ha-1 C) than in Pr (0.19 ± 0.09 t ha-1 C). The highest accumulation of CBR (1.16 ± 3.76 t ha-1 C) and CLIT (3.09 ± 2.45 t ha-1 C) occurred in SSP2. The soil organic carbon accumulated (COS) values showed higher accumulation in the first stratum. The COS represented in the three systems more than 70 % of the total contribution in accumulated carbon contribution. Conclusion. Under the environmental conditions of the humid tropical dry forest, silvopastoral systems increased the stock of atmospheric carbon in the soil and biomass. The use of SSP is a strategy in the mitigation of greenhouse gases in the livestock production system., Introducción. Los sistemas silvopastoriles tienen un papel importante en la producción ganadera, aportan beneficios a los componentes animal y edáfico, ofrecen servicios ambientales como la captura de carbono atmosférico en el suelo y la biomasa. Objetivo. Evaluar la capacidad de captura de carbono atmosférico en tres sistemas de diferentes complejidades enfocados a la producción ganadera, en el norte de Colombia. Materiales y métodos. El estudio se llevó a cabo en el Centro de Investigación Turipaná de la Corporación Colombiana de Investigación Agropecuaria entre 2019 y 2021. Se evaluaron parámetros dasométricos del componente arbóreo/arbustivo. Se estimó la biomasa aérea (CBA) y subterránea (CBR) de estas especies con modelos alométricos. Se cuantificó la biomasa de hojarasca caída (CLIT) y el carbono orgánico en el suelo hasta los 30 cm, con lecturas cada 10 cm, por el método de combustión y carbono total acumulado. El diseño correspondió a bloques completos al azar, con tres tratamientos y cuatro repeticiones. Los tratamientos correspondieron a dos sistemas silvopastoriles (SSP) de diferente complejidad y una gramínea sin árboles (Pr). Resultados. La biomasa aérea fue mayor dentro los SSP (2,18±1,13, 4,51±3,76 t ha-1 C) que en Pr (0,19±0,09 t ha-1 C). En SSP2 se presentó la mayor acumulación de CBR (1,16±3,76 t ha-1 C) y CLIT (3,09±2,45 t ha-1 C). Los valores de carbono orgánico acumulado en el suelo (COS), mostraron mayor acumulación en el primer estrato. El COS representó en los tres sistemas más del 70 % del aporte total en carbono acumulado. Conclusión. Bajo las condiciones ambientales de bosque seco tropical húmedo, los sistemas silvopastoriles aumentaron la reserva de carbono atmosférico en el suelo y en la biomasa; el uso de SSP es una estrategia en la mitigación de gases de efecto invernadero en el sistema productivo ganadero.

The geographical location, climate, topography and most important human interference has contributed to the characteristic flora of the old campus of University of Jammu. A total of 24 tree species having 153 individuals belonging to 14 families have been recorded. Out of 24, 23 species belong to Angiosperms (22 dicots and 1 monocot) whereas, only 1 species belong to Gymnosperms. Overall, Moraceae was found to be the dominant family. The total growing stock, total biomass, total carbon content within university campus has been assessed to be 215663.99cm3, 107.83kg, 50.68kg respectively. The total CO2 sequestered by trees and net oxygen produced have been estimated to be 185.84kg and 495.65kg, respectively. Thus, the old campus of University of Jammu with lot of built-up area, roads, lawns, parking places, garden, etc. has sequestered considerably good amount of carbon and also produced considerable amount of oxygen as compared to its size, and its potential for sequestration can be enhanced with the help of management practices and plantation of more trees/shrubs within the permissible areas.

The geographical location, climate, topography and most important human interference has contributed to the characteristic flora of the old campus of University of Jammu. A total of 24 tree species having 153 individuals belonging to 14 families have been recorded. Out of 24, 23 species belong to Angiosperms (22 dicots and 1 monocot) whereas, only 1 species belong to Gymnosperms. Overall, Moraceae was found to be the dominant family. The total growing stock, total biomass, total carbon content within university campus has been assessed to be 215663.99cm3, 107.83kg, 50.68kg respectively. The total CO2 sequestered by trees and net oxygen produced have been estimated to be 185.84kg and 495.65kg, respectively. Thus, the old campus of University of Jammu with lot of built-up area, roads, lawns, parking places, garden, etc. has sequestered considerably good amount of carbon and also produced considerable amount of oxygen as compared to its size, and its potential for sequestration can be enhanced with the help of management practices and plantation of more trees/shrubs within the permissible areas.

The geographical location, climate, topography and most important human interference has contributed to the characteristic flora of the old campus of University of Jammu. A total of 24 tree species having 153 individuals belonging to 14 families have been recorded. Out of 24, 23 species belong to Angiosperms (22 dicots and 1 monocot) whereas, only 1 species belong to Gymnosperms. Overall, Moraceae was found to be the dominant family. The total growing stock, total biomass, total carbon content within university campus has been assessed to be 215663.99cm3, 107.83kg, 50.68kg respectively. The total CO2 sequestered by trees and net oxygen produced have been estimated to be 185.84kg and 495.65kg, respectively. Thus, the old campus of University of Jammu with lot of built-up area, roads, lawns, parking places, garden, etc. has sequestered considerably good amount of carbon and also produced considerable amount of oxygen as compared to its size, and its potential for sequestration can be enhanced with the help of management practices and plantation of more trees/shrubs within the permissible areas.

The geographical location, climate, topography and most important human interference has contributed to the characteristic flora of the old campus of University of Jammu. A total of 24 tree species having 153 individuals belonging to 14 families have been recorded. Out of 24, 23 species belong to Angiosperms (22 dicots and 1 monocot) whereas, only 1 species belong to Gymnosperms. Overall, Moraceae was found to be the dominant family. The total growing stock, total biomass, total carbon content within university campus has been assessed to be 215663.99cm3, 107.83kg, 50.68kg respectively. The total CO2 sequestered by trees and net oxygen produced have been estimated to be 185.84kg and 495.65kg, respectively. Thus, the old campus of University of Jammu with lot of built-up area, roads, lawns, parking places, garden, etc. has sequestered considerably good amount of carbon and also produced considerable amount of oxygen as compared to its size, and its potential for sequestration can be enhanced with the help of management practices and plantation of more trees/shrubs within the permissible areas.

Broad‐leaved dock (Rumex obtusifolius L.) is a troublesome weed that predominantly grows in pastures and grassland. We hypothesised that frequent defoliation of Rumex will, over time, result in a reduction in root weight and leaf area, to the point where the impact on grass production is negligible. In order to investigate this hypothesis, we conducted three experiments. The objective of the first experiment was to perform a preliminary test of the hypothesis, using potted plants growing in the controlled conditions of a glasshouse. This experiment showed a rapid decline in leaf growth in plants that were defoliated weekly. The objective of the second experiment was to test the hypothesis in realistic outdoor conditions while still being able to collect detailed plant growth information. This experiment confirmed the findings of the glasshouse experiment and provided evidence that leaf growth ceased as a result of a dwindling supply of carbohydrate reserves in the root. Defoliated plants did not exhibit increased mortality. Finally, the objective of the third experiment was to test the hypothesis in a commercial pasture where normal field operations, specifically grass harvesting (three times) and slurry injection (twice), were performed. The results of this experiment were consistent with the results of the other two experiments. We conclude that weekly defoliation, maintained for three or more months, is an effective method to control (reduce the impact on grass production), but not kill, R. obtusifolius in pasture.

Efforts to understand why some species become successful invaders and why some habitats are more at risk from invasive species is an important research focus in invasion ecology. With current global climate change, evaluation of the effects of shade and drought on cohabiting native and invasive species from extreme ecosystems is especially important. Acacia tortilis subsp. raddiana is a tree taxon native to arid African deserts. Prosopis glandulosa, native to the southwestern United States and Mexico, is invading African arid and semiarid regions that are habitat for A. t. subsp. raddiana. The aim of this study was to evaluate and compare the tolerance and responses of the seedlings of these two tree species to shade, water stress and their interactions. We measured and recorded growth rates and morphological, biochemical and physiological plant traits under two radiation and two water treatments in greenhouse conditions. Radiation intensity was a stronger driver of the performance of both species than water availability. Beyond the independent effects of shade and drought, the interactions of these factors yielded synergistic effects on seedlings of both tree species, affecting key plant traits. The seedlings of A. t. subsp. raddiana were able to implement important shifts in key functional traits in response to altering abiotic stress conditions, behaving as a stress-tolerant species that is well-adapted to the habitat it occupies in hot arid African deserts. In contrast, the fast-growing seedlings of P. glandulosa were stress-avoiding. The alien P. glandulosa seedlings were highly sensitive to water and shade stress. Moreover, they were particularly sensitive to drought in shade conditions. However, although alien P. glandulosa seedlings were exposed to high stress levels, they were able to avoid permanent damage to their photosynthetic apparatus by mechanisms such as increasing energy dissipation by heat emission and by adjusting the relative allocation of resou

Efforts to understand why some species become successful invaders and why some habitats are more at risk from invasive species is an important research focus in invasion ecology. With current global climate change, evaluation of the effects of shade and drought on cohabiting native and invasive species from extreme ecosystems is especially important. Acacia tortilis subsp. raddiana is a tree taxon native to arid African deserts. Prosopis glandulosa, native to the southwestern United States and Mexico, is invading African arid and semiarid regions that are habitat for A. t. subsp. raddiana. The aim of this study was to evaluate and compare the tolerance and responses of the seedlings of these two tree species to shade, water stress and their interactions. We measured and recorded growth rates and morphological, biochemical and physiological plant traits under two radiation and two water treatments in greenhouse conditions. Radiation intensity was a stronger driver of the performance of both species than water availability. Beyond the independent effects of shade and drought, the interactions of these factors yielded synergistic effects on seedlings of both tree species, affecting key plant traits. The seedlings of A. t. subsp. raddiana were able to implement important shifts in key functional traits in response to altering abiotic stress conditions, behaving as a stress-tolerant species that is well-adapted to the habitat it occupies in hot arid African deserts. In contrast, the fast-growing seedlings of P. glandulosa were stress-avoiding. The alien P. glandulosa seedlings were highly sensitive to water and shade stress. Moreover, they were particularly sensitive to drought in shade conditions. However, although alien P. glandulosa seedlings were exposed to high stress levels, they were able to avoid permanent damage to their photosynthetic apparatus by mechanisms such as increasing energy dissipation by heat emission and by adjusting the relative allocation of resou

Efforts to understand why some species become successful invaders and why some habitats are more at risk from invasive species is an important research focus in invasion ecology. With current global climate change, evaluation of the effects of shade and drought on cohabiting native and invasive species from extreme ecosystems is especially important. Acacia tortilis subsp. raddiana is a tree taxon native to arid African deserts. Prosopis glandulosa, native to the southwestern United States and Mexico, is invading African arid and semiarid regions that are habitat for A. t. subsp. raddiana. The aim of this study was to evaluate and compare the tolerance and responses of the seedlings of these two tree species to shade, water stress and their interactions. We measured and recorded growth rates and morphological, biochemical and physiological plant traits under two radiation and two water treatments in greenhouse conditions. Radiation intensity was a stronger driver of the performance of both species than water availability. Beyond the independent effects of shade and drought, the interactions of these factors yielded synergistic effects on seedlings of both tree species, affecting key plant traits. The seedlings of A. t. subsp. raddiana were able to implement important shifts in key functional traits in response to altering abiotic stress conditions, behaving as a stress-tolerant species that is well-adapted to the habitat it occupies in hot arid African deserts. In contrast, the fast-growing seedlings of P. glandulosa were stress-avoiding. The alien P. glandulosa seedlings were highly sensitive to water and shade stress. Moreover, they were particularly sensitive to drought in shade conditions. However, although alien P. glandulosa seedlings were exposed to high stress levels, they were able to avoid permanent damage to their photosynthetic apparatus by mechanisms such as increasing energy dissipation by heat emission and by adjusting the relative allocation of resou

Efforts to understand why some species become successful invaders and why some habitats are more at risk from invasive species is an important research focus in invasion ecology. With current global climate change, evaluation of the effects of shade and drought on cohabiting native and invasive species from extreme ecosystems is especially important. Acacia tortilis subsp. raddiana is a tree taxon native to arid African deserts. Prosopis glandulosa, native to the southwestern United States and Mexico, is invading African arid and semiarid regions that are habitat for A. t. subsp. raddiana. The aim of this study was to evaluate and compare the tolerance and responses of the seedlings of these two tree species to shade, water stress and their interactions. We measured and recorded growth rates and morphological, biochemical and physiological plant traits under two radiation and two water treatments in greenhouse conditions. Radiation intensity was a stronger driver of the performance of both species than water availability. Beyond the independent effects of shade and drought, the interactions of these factors yielded synergistic effects on seedlings of both tree species, affecting key plant traits. The seedlings of A. t. subsp. raddiana were able to implement important shifts in key functional traits in response to altering abiotic stress conditions, behaving as a stress-tolerant species that is well-adapted to the habitat it occupies in hot arid African deserts. In contrast, the fast-growing seedlings of P. glandulosa were stress-avoiding. The alien P. glandulosa seedlings were highly sensitive to water and shade stress. Moreover, they were particularly sensitive to drought in shade conditions. However, although alien P. glandulosa seedlings were exposed to high stress levels, they were able to avoid permanent damage to their photosynthetic apparatus by mechanisms such as increasing energy dissipation by heat emission and by adjusting the relative allocation of resou

Wetlands serve important ecosystem functions such as carbon sequestration but are often affected by disturbances like urban development, agriculture, and road building. For wetlands created to mitigate losses, it is important that the ecosystem functions successfully replicate those of natural wetlands. Created wetlands have frequently not provided these functions due to issues including low organic carbon (OC), high soil bulk density (BD), lost topsoil, incorrect hydrology, and failure of targeted vegetation establishment. Organic matter (OM) amendments help created wetlands attain these functions quicker, but, their long-term effects are seldom reported. This research's purpose was to measure the long-term effects of treatments at a sandy tidal freshwater wetland created in 2003 (WWE) and a fine-textured, non-tidal wetland created in 2002 (CCW). We tested OM treatments, topsoil amendment, and microtopography effects on soil and vegetation properties at WWE and OM treatments at CCW. Pedogenic changes in soil morphology, physical and chemical properties were detected by comparing data to previous studies at these sites. At both sites, litter and biomass parameters were measured to estimate total mass C. Herbaceous biomass was measured at WWE. At WWE, no long-term OM treatment effects from 78 or 156 Mg ha-1 were observed. Soils in pits had higher OC, lower BD, and lower chroma than soils on mounds. Sandy and loamy HSFI's developed at WWE within four years, but there were fewer sandy indicators after 12 years. Loamy HSFI's were lost at CCW from 2003 to 2016. Plots at WWE that were amended with topsoil had higher soil mass C than the sandy soil due to a finer texture, but total mass C did not vary. At CCW, long-term OM treatment effects were observed, including lower BD, higher soil mass C, and higher tree mass C with increasing compost rates up to 224 Mg ha-1. Overall, the ideal compost loading rate for constructed wetlands varied with wetland type and mitigation goal

Understanding carbon (C) stocks or biomass in forests is important to examine how forests mitigate climate change. To estimate biomass in stems, branches and roots takes intensive fieldwork to uproot, cut and weigh the mass of each component. Different models or equations are also required. Our research focussed on the dry tropical Zambezi teak forests and we studied their structure at three sites following a rainfall gradient in Zambia. We sampled 3558 trees at 42 plots covering a combined area of 15ha. Using data from destructive tree samples, we developed mixed-species biomass models to estimate above ground biomass for small (<5 cm diameter at breast height (DBH, 1.3 m above-ground)) and large (≥5 cm DBH) trees involving 90 and 104 trees respectively, that belonged to 12 species. A below-ground biomass model was developed from seven trees of three species (16–44 cm DBH) whose complete root systems were excavated. Three stump models were also derived from these uprooted trees. Finally, we determined the C fractions from 194 trees that belonged to 12 species. The analysis revealed that DBH was the only predictor that significantly correlated to both above-ground and below-ground biomass. We found a mean root-to-shoot ratio of 0.38:0.62. The C fraction in leaves ranged from 39% to 42%, while it varied between 41% and 46% in wood. The C fraction was highest at the Kabompo site that received the highest rainfall, and lowest at the intermediate Namwala site. The C stocks varied between 15 and 36 ton C ha−1 and these stocks where highest at the wetter Kabompo site and lowest at the drier Sesheke site. Our results indicate that the projected future rainfall decrease for southern Africa, will likely reduce the C storage potential of the Zambezi teak forests, thereby adversely affecting their mitigating role in climate change.

Aim of the study: To analyse the decline in aged holm oak coppice forests as regards above-ground and below-ground fractions and physiological features.Area of study: Centre of the Iberian Peninsula (Guadalajara province).Material and methods: 26 pairs of holm oak stools with different vigour but with similar site and structural characteristics within each pair were selected. Morphological (basal area, number of stools, maximum height) and physiological traits (leaf water potential, stomatal conductance) of the standing stools were assessed. Their aerial and underground parts were extracted and different size fractions of both their above and below-ground biomass were quantified. Linear mixed models were built to test the effect of ’Stool vigour’ on the mean behaviour of the measured variables. Additionally, for the aerial part, linear regressions between the weights of the different size fractions and the basal area at breast height were performed using ‘Stool vigour’ as a fixed factor.Main results: For the same site, root depth, and number and diameter of shoots than good vigour stools, poor vigour stools displayed: lower predawn water potential, greater leaf mass per unit of area; lower total leaf area; lower above-ground biomass (in total as well as per fractions); lower fine roots biomass; lower proportion of leaf biomass and a greater proportion of biomass of both all roots and those with diameter 2-7 cm.Research highlights: The above-ground physiological and morphological characteristics of declined stools are interpreted as poorer adaptation to site conditions. Root system architecture was found to be relevant to explain this behaviour.

Aim of the study: To analyse the decline in aged holm oak coppice forests as regards above-ground and below-ground fractions and physiological features.Area of study: Centre of the Iberian Peninsula (Guadalajara province).Material and methods: 26 pairs of holm oak stools with different vigour but with similar site and structural characteristics within each pair were selected. Morphological (basal area, number of stools, maximum height) and physiological traits (leaf water potential, stomatal conductance) of the standing stools were assessed. Their aerial and underground parts were extracted and different size fractions of both their above and below-ground biomass were quantified. Linear mixed models were built to test the effect of ’Stool vigour’ on the mean behaviour of the measured variables. Additionally, for the aerial part, linear regressions between the weights of the different size fractions and the basal area at breast height were performed using ‘Stool vigour’ as a fixed factor.Main results: For the same site, root depth, and number and diameter of shoots than good vigour stools, poor vigour stools displayed: lower predawn water potential, greater leaf mass per unit of area; lower total leaf area; lower above-ground biomass (in total as well as per fractions); lower fine roots biomass; lower proportion of leaf biomass and a greater proportion of biomass of both all roots and those with diameter 2-7 cm.Research highlights: The above-ground physiological and morphological characteristics of declined stools are interpreted as poorer adaptation to site conditions. Root system architecture was found to be relevant to explain this behaviour.

In Malaysia, the main land change process is the establishment of oil palm plantations on logged-over forests and areas used for shifting cultivation, which is the traditional farming system. While standing carbon stocks of old-growth forest have been the focus of many studies, this is less the case for Malaysian fallow systems and oil palm plantations. Here, we collate and analyse Malaysian datasets on total carbon stocks for both above- and below-ground biomass. We review the current knowledge on standing carbon stocks of 1) different forest ecosystems, 2) areas subject to shifting cultivation (fallow forests) and 3) oil palm plantations. The forest ecosystems are classified by successional stage and edaphic conditions and represent samples along a forest succession continuum spanning pioneer species in shifting cultivation fallows to climax vegetation in old-growth forests. Total carbon stocks in tropical forests range from 4 to 384MgC/ha, significantly wider than the range of total carbon stocks of oil palm plantations, 2 to 60MgC/ha. Conversion of old-growth forest areas to oil palm plantations leads to substantial reduction in carbon storage, while conversion of forest fallows to oil palm plantations may sustain or even increase the standing carbon stock.

Tea (Camellia sinensis L.) is a perennial evergreen shrub managed intensively for continuous growth of young shoots. Most tea plantations were established at the expense of native forest. Change in carbon (C) and nutrient (nitrogen, phosphorus, potassium (NPK)) accumulation in forests over time has been intensively studied, but how C and NPK stocks in tea plantations are associated with age, genotype and plant density have not been reported yet in literature. To get a better insight in the effects of age and the associated change in genotype (clone or seedling) and density on C and NPK stocks data were collected in a chronosequence of tea plantations by destructive sampling of whole tea bushes. Four plantations differing in age (76-, 43-, 29- and 14-year old) and genotype¿density combinations were selected. The 76- and 43-year old plantations were composed of seedlings planted at a relative low density: a spacing of 1.52¿×¿0.91 m and 1.22¿×¿1.22 m, respectively, whereas in the 29- and 14-year old plantations an improved clonal cultivar was grown at higher plant densities: a spacing of 1.22¿×¿0.61 m and 1.22¿×¿0.76 m, respectively. Total dry matter weights (DM) of tea bushes increased with age from 9.0 to 11.5 kg in clonal bushes and from 13.5 and 19.9 kg in seedling bushes for the 14- and 29-year, and the 43- and 76-year old plantations, respectively. Most DM was stored in the woody tissue of the tea bush frame. Total C- stocks expressed per unit area (ha) amounted to 44 and 72, and 43 and 69 t C ha¿1 for clonal and seedling bushes, respectively. Total N stocks ranged from 732 to 995 and from 734 to 1,200 kg ha¿1, P stocks from 78 to 120 and from 67 to 92 kg ha¿1, and K stocks from 775 to 901 and from 646 to 1,120 kg ha¿1 for clonal and seedling bushes, respectively. It is concluded that older stands of seedling and clonal tea plantations result in higher C and NPK stocks. Higher stocks may be functional in maintaining yield stability under adverse weather condition

Fine roots (< 2 mm) are very dynamic and play a key role in forest ecosystem carbon and nutrient cycling and accumulation. We reviewed root biomass data of three main European tree species European beech, (Fagus sylvatica L.), Norway spruce (Picea abies L. Karst.) and Scots pine (Pinus sylvestris L.), in order to identify the differences between species, and within and between vegetation zones, and to show the relationships between root biomass and the climatic, site and stand factors. The collected literature consisted of data from 36 beech, 71 spruce and 43 pine stands. The mean fine root biomass of beech was 389 g m(-2), and that of spruce and pine 297 g m(-2) and 277 g m(-2), respectively. Data from pine stands supported the hypothesis that: root biomass is higher in the temperate than in the boreal zone. The results indicated that the root biomass of deciduous trees is higher than that of conifers. The correlations between root biomass and site fertility characteristics seemed to be species specific. There was no correlation between soil acidity and root biomass. Beech fine root. biomass decreased with stand age whereas pine root biomass increased with stand age. Fine root biomass at tree level. correlated better than stand level root biomass with stand characteristics. The results showed that there exists a strong relationship between the fine root biomass and the above-ground biomass.