We assessed numbers and biomass of species hunted and sold for wild meat in 12 park-adjacent settlements in the Fazao Malfakassa National Park (FMNP), Togo. From hunter interviews and market carcass counts, 33 species, 28 from hunter interviews and 26 from market surveys were taken, respectively. A total of 2605 animals were recorded in the study, 18 species during the wet season (740 animals) and 26 species in the dry season (1865 animals). In markets, 754 carcasses of 19 species were traded during the wet season, and 1896 carcasses of 24 species in the dry season. Most species were relatively small-bodied mammals (62% of total numbers of animals reported), the rest large ungulates. Species were generally of minor conservation concern (LC or NT) with only three EN and NE. From the gathered field data, we estimated that an average of 9095 ± 5613 animals per study village were hunted per year, amounting to a biomass of 198,334 ± 191,930 kg. Despite efforts to protect the wildlife within the FMNP, reported level of hunting, particularly of large ungulates within the park, the reported level of hunting is likely to have severe consequences on the long-term viability of this important protected area.
Tag: biomass
Optimum plant density and harvest age for maximizing productivity and minimizing competition in a Calliandra short-rotation-coppice plantation in West Java, Indonesia
To produce large volumes of biomass for implementing its green energy policy, the Government of Indonesia has issued a short rotation energy plantation program for a number of tree species including Calliandra calothyrsus (Meissn.). Optimum density and prompt harvesting are needed to maximise productivity, but information regarding both factors is insufficient. This study aimed to investigate the optimum growth spacing and ideal felling age to produce the largest volumes of biomass both economically and sustainably. Experiments were arranged on one hectare of land, which was divided into four plots with different plant spacing treatments (1 × 1.5 m; 1.5 × 1.5 m; 2 × 1.5 m; and 2 × 2 m). Growth and yield observations were carried out on plants aged 12, 18, and 24 months in each plot, with 30 sample trees left for growth observations and ten sample trees cut at each of the three ages after planting. This resulted in a total of 240 samples from the 2,710 trees planted. Trees were felled at 50 cm from the soil surface, and the resulting stools were left to regrow. A year after felling, resulting coppices, were observed and cut. Growth, productivity and calorific value were studied for both ‘primary’ and ‘coppiced’ wood. Study results demonstrate that competition between plants strongly determines the growth and productivity of ‘primary’ wood. The plot with the densest plant spacing had the lowest nutrient content for almost all soil nutrients. Higher plant density showed higher competition index values, and resulted in fewer and smaller diameter stems emerging from stools, and lower biomass productivity. Competition index values, which increased with plant age, can be used as an indicator for determining harvest timing. Productivity increased by up to 15% following development as a coppice plantation. Optimum wood productivity and greatest economy came from parent stands with plant spacing of 2 × 2 m, harvested at 18 months old and coppiced. This treatment yielded an average biomass/tree of primary wood 7.2 kg and coppice wood 8.22 kg, respectively, with lignin content of approximately 22%, and calorific value of around 18,807 kJ. These values match biomass energy requirements for feedstock for electricity generation. Harvesting at 24 months showed no significant increases in productivity, lignin content, or calorific value.
FTA Highlight No.8 – Biomass, Bioenergy and Biomaterials
The demand for woody biomass for energy and biomaterials is increasing rapidly in line with the global population rise and changing consumption patterns for sustainable resources. Central to meeting this demand is the question of how woody biomass production and use can be reconciled with biodiversity protection, climate change resilience and mitigation, and inclusive prosperity for local communities. Modern, efficient and sustainable forms of bioenergy and biomaterial production and use can play a key role in combating climate change while providing social, economic and environmental benefits to rural communities and critical industries, but these forms are not available to everyone. Thus, attention to social inclusion in the development agendas related to sustainable biomass production, use and trade is vital. Over the last decade, the CGIAR Research Program on Forests, Trees and Agroforestry (FTA) has undertaken basic and applied research on multiple dimensions of woody biomass production and use for energy and materials, such as sustainable production, value chains and investments, enterprise development, and green growth through forest and tree-based circular economies. This highlight discusses the key outputs and findings from FTA work on biomass production and use for bioenergy and biomaterials, in particular woody biomass production in forests and plantations and on farms; the use of biomass; and related value chains. It also considers work on policies that promote sustainability in the sector and discusses the requirements for a shift to a forest- and tree-based bioeconomy.
Trees enhance abundance of arbuscular mycorrhizal fungi, soil structure, and nutrient retention in low-input maize cropping systems
Retaining trees in low-input agroecosystems could be key to maintain mycelia of arbuscular mycorrhizal fungi (AMF) and hence, improve soil fertility and crop performance. We assessed the impact of faidherbia (Faidherbia albida, Fabaceae) and mango (Mangifera indica, Anacardiaceae) trees on AMF and soil fertility in smallholder farmers’ maize fields. Along distance-from-tree gradients (1, 4, 10, 15 m), we collected soil to assess AMF hyphal density, soil aggregation, and aggregate-associated carbon (C), nitrogen (N), and phosphorus (P) at the end of the non-cropping season. Further, we determined maize biomass and yield. The impact of faidherbia on maize N nutrition was assessed using the 15N natural abundance methodology. Our results show that hyphal density was largest at 4 and 10 m from trees and greater around faidherbia than mango. Soil aggregation decreased with distance from mango and was greater around faidherbia than mango. Macroaggregate-associated C, N, and P decreased with distance-from-tree, due to differences in aggregate distribution. Maize biomass was smallest at 1 m from trees and did not differ when under faidherbia versus mango. On average 69 ± 14, 24 ± 9, 20 ± 6, and 12 ± 5% of total foliar N of maize grown at 1, 4, 10, and 15 m from faidherbia trees was tree-derived. Our results suggest that faidherbia and mango trees can maintain AMF mycelia and combat declining soil fertility. Faidherbia is particularly suited to enhance measured soil parameters commonly associated with soil fertility and alleviate soil mining for N via improved internal N cycling. As such, agroforestry trees can contribute to a more sustainable agriculture positively affecting the environment via mitigating soil degradation. © 2021
Mangrove selective logging sustains biomass carbon recovery, soil carbon, and sediment
West Papua’s Bintuni Bay is Indonesia’s largest contiguous mangrove block, only second to the world’s largest mangrove in the Sundarbans, Bangladesh. As almost 40% of these mangroves are designated production forest, we assessed the effects of commercial logging on forest structure, biomass recovery, and soil carbon stocks and burial in five-year intervals, up to 25 years post-harvest. Through remote sensing and field surveys, we found that canopy structure and species diversity were gradually enhanced following biomass recovery. Carbon pools preserved in soil were supported by similar rates of carbon burial before and after logging. Our results show that mangrove forest management maintained between 70 and 75% of the total ecosystem carbon stocks, and 15–20% returned to the ecosystem after 15–25 years. This analysis suggests that mangroves managed through selective logging provide an opportunity for coastal nature-based climate solutions, while provisioning other ecosystem services, including wood and wood products.
Biomass estimation models for Acacia saligna trees in restored landscapes
Acacia saligna, originating from Australia, is a naturalized multipurpose tree species widely grown to restore degraded lands of Africa. The contribution of A. saligna in biomass restoration can be quantified using a precise estimation of tree biomass carbon. This study developed species-specific allometric models and evaluated the spatial variation of tree biomass across restored areas in exclosures and open grazing landscapes. These models could play a considerable role in the monitoring of carbon dynamics across A. saligna planation dominated areas. We harvested, excavated, and weighed twenty-one sample trees representing different size classes to develop allometric models for the estimation of aboveground (AGB), belowground (BGB) and total tree (TB) biomass. The average dry-to-fresh mass ratio and the root-to-shoot ratio was 0.47 (±0.13) and 0.28 (±0.14), respectively. Tree biomass significantly correlated with diameter at breast height (r = 0.93; P < 0.001), diameter at stump height (r = 0.88, P < 0.001) and tree height (r = 0.56, P < 0.05). Our best biomass estimation models explained 86%, 82% and 87% of variations in AGB, BGB, and TB, respectively. Models using DSH and DSH & H explained 70%–78% of the variation in AGB, BGB, and TB. Estimated C-stock showed a significant relationship with stem density (R2= 0.91, P < 0.01). Estimated TB varied between 1.5–18 Mg ha−1 on grazed land and exclosures. Estimated C-stocks in the exclosure exceeded the estimated C-stock in the open grazing land by ∼60%. This implies that with proper management practices and enrichment planting A. saligna significantly contributes to increasing carbon accumulation on degraded landscapes, playing a key role in climate change mitigation efforts while improving land productivity.
Allometric equations, wood density and partitioning of aboveground biomass in the arboretum of Ruhande, Rwanda
There is growing interest in plantation forests throughout Africa because of their role in environment, economy and people’s livelihoods. However, the contribution of planted forests to climate mitigation is poorly understood, partly due to lack of allometric equations for biomass estimation. This study aimed to determine wood density and biomass fractions in aboveground components, and to develop biomass estimation equations for multispecies plantation forests in the arboretum of Ruhande in Rwanda. Allometric equations were developed by regressing diameter at breast height (DBH) alone or in combination with height or wood density or age of trees against the biomass of 45 trees harvested from a 200-ha site. Biomass estimates obtained from destructively sampled trees were up-scaled to estimate the amount of carbon stocked in the arboretum of Ruhande, assuming a stem density of 250 stems per ha. Wood density varied among the species but not tree size. The greatest fraction of aboveground biomass was allocated to stems (71–77%) compared to branches (19–27%) and leaves (1–8%) and varied by species. Equations developed fit the data well with DBH explaining over 90% of the observed variation in aboveground and stem biomass. Including height or wood density as supporting parameters reduced the relative error for aboveground biomass by 6.4 and 8.0% and improved model fit by 2.1 and 2.9%, respectively. Akaike information criterion (AIC) showed that wood density (AIC=63.6) and height (AIC=48.2) were the most suitable parameters to support DBH as a proxy for aboveground and stem biomass, respectively. Allometric equations developed in this study are useful tool for estimating carbon stocks of plantation forests in Rwanda and can enhance the accuracy of biomass predictions where site-specific equations rather than generalized models are recommended. Further studies focusing on development of allometric equations on belowground biomass in such systems are recommended.
The potentials of technology complementarity to address energy poverty in refugee hosting landscapes in Uganda
The continued influx of refugees into Uganda confronts people and hosting landscapes with severe challenges. Vast volumes of biomass resources are required for energy and building materials. Consequently, woodlands have come under pressure as the key source within refugee-receiving regions. This raises the question of how to simultaneously achieve a higher standard of living and energy autonomy for the population while reducing primary resource demand and safeguarding nature. We propose that nature-based and/or technological adaptions can ameliorate this dramatic and deteriorating situation. We thus evaluated the impact of: (i) building autonomy by growing biomass resources on scale via approaches such as agroforestry and ii) enhancing energy efficiency through use of improved cook stoves (ICS) and switching toward renewable energy sources. Focusing on four Ugandan districts, we analyzed the energy and land demand of households and districts in three scenarios. Our results show all districts running into shortages of biomass resources and cultivable land and two districts already reaching their limits. An efficient use of woodfuel combined with solar energy could reduce primary energy demand by up to 37%. The remaining wood demand could be realized by agroforestry systems thereby ensuring household energy autonomy and access to reliable energy sources. We recommend combining energy efficiency measures and technology to reduce firewood demand with agroforestry solutions to satisfy the remaining necessities. Both are needed to reduce the essistential pressure on woodlands and increase the energy autonomy of refugee-hosting landscapes while respecting stakeholder needs.
Spatial analysis of area and carbon stocks under Populus deltoides based agroforestry systems in Punjab and Haryana states of Indo-Gangetic Plains
Utilizing Mathenge (Prosopis Juliflora) for Charcoal: The Other Side of an Invasive Species
The study used Focused Group Discussions (FGD), seasonal and livelihood calendars, participatory visioning and mapping and training of trainers delivered in partnership with KEFRI. Analysis from the project has showed that the species has potential to provide communities with 14 different products and services with charcoal ranking highest and food for humans the lowest. In terms of contribution to livelihoods, both men and women rank charcoal among the top three livelihood sources after farming and livestock keeping. Pods, another product from Prosopis can be sold as feed for livestock at KES 100 (USD1) per 50kg bag. Management by utilization of the almost 19,000 hectares of Prosopis juliflora in Baringo for sustainable charcoal production presents potential for improving livelihoods and the environment. It presents an opportunity for supplying the growing urban centers with affordable cooking fuel, a strategy that can be scaled out to the other affected counties. Also, there is need for complete removal of mathenge in some pockets to create room for enrichment with native high value multipurpose tree species to enhance biodiversity.