Total Annual Biomass Research Articles

Biomass and nutrient flow dynamics and sustainability practices to de-risk environmental challenges in the sub-saharan Africa farming system

In sub-Saharan Africa, productivity risks stem from weather variability, while environmental risks include soil nutrient depletion due to unsustainable farming practices that include monoculture, inadequate or lack of soil and water conservation measures, and low-nutrient application. As a result, shifts from the prevailing fallow system to permanent cultivation lead to soil degradation. The present study aimed to quantify the fluxes of biomass, nutrients, and nutrient balances from different fertilizer sources to de-risk the challenges related to agriculture and the environment in Mali. A farm household survey was conducted over two years (July 2018 to June 2020) with 45 households. The survey enabled us to categorize farm households into three typologies: high resource endowment (HRE), medium resource endowment (MRE), and low resource endowment (LRE). Data on sustainability indicators from cropland, livestock, farm input use, and redistribution units enabled the analysis of biomass and nutrient flow dynamics from households to farmlands and vice versa. The nutrient monitoring (NUTMON) tool generated nutrient flows and balances. Results showed that the total annual biomass collected per hectare by HRE (22.3t) is significantly higher than that collected by MRE (13.4t) and LRE (5.35t) farms (P ​< ​0.001). Compared to LRE (10.3 ​t ​ha−1 year−1), HRE and MRE farmers produced six times (60 ​t ​ha−1 year−1) and three times (34 ​t ​ha−1 year−1) more manure, respectively. Farm households with better endowment status observed a higher rate of nutrient utilization. For the major crops, nutrient application rates of HRE farms in kg ha−1 (cotton: 12.6 ​N, 4.2 ​P, 18.2 ​K) and (maize: 9.18 ​N, 2.34 ​P, 10.7 ​K) were significantly higher than that of MRE and LRE farms (P ​< ​0.01). The study confirms that household endowment status determines farmlands' nutrient flows and fertility levels. Quantifying biomass transport and understanding nutrient flow dynamics enable the derivation of context-specific solutions to reduce risks associated with productivity and the environment.

Harvest frequency and harvest timing following a freeze event effects on yield and composition of switchgrass

AbstractConstant supply of biomass from the field is limited by the seasonality of production of warm‐season grasses in the transition U.S. region. Delaying harvest after occurrence of freeze may be an alternative to extend the biomass supply period of switchgrass (Panicum virgatum L.) in North Carolina. The objectives of this study were to evaluate the effects of harvest frequency (HF) and harvest timing at the end of the growing season (HT) on switchgrass biomass yield, nutrient (N, P, and K) removal, and dry matter (DM) and ash concentrations. Treatments were the factorial combination of two HF (clipped once [1X] or twice [2X] per season) and three HT (before freeze in October, after first freeze in November, and late winter in February). Delaying harvest after occurrence of freeze did not affect total annual biomass yield for the 2X treatment (average of 15.5 Mg ha−1), whereas for 1X yield declined from 14.4 to 10.1 Mg ha−1 when harvest was delayed from October to February. Ash concentration declined from 29 g kg−1 in October to 14 g kg−1 in February. The DM concentration level reached in February was lowest (893 g kg−1) and it would be considered safe for storage of biomass. Nutrient removal was consistently greater for 2X than 1X (ranging from 43 to 137, 3.6 to 25.1, and 54 to 213 kg ha−1 for N, P, K, respectively). Delaying harvest of switchgrass after a freeze event is feasible when clipping twice a year to extend the window of biomass supply.

An Assessment of the Potential Use of Forest Residues for the Production of Bio-Oils in the Urban-Rural Interface of Louisiana

Louisiana is endowed with forest resources. Forest wastes generated after thinning, land clearing, and logging operations, such as wood debris, tree trimmings, barks, sawdust, wood chips, and black liquor, among others, can serve as potential fuels for energy production in Louisiana. This paper aims to evaluate the potential annual volumes of forest wastes established on detailed and existing data on the forest structure in the rural-urban interface of Louisiana. It also demonstrates the state’s prospects of utilizing forest wastes to produce bio-oils. The data specific to the study was deduced from secondary data sources to obtain the annual average total residue production in Louisiana and estimate the number of logging residues available for procurement for bioenergy production. The total biomass production per year was modeled versus years by polynomial regression curve fitting using Microsoft Excel. Results of the model show that the cumulative annual total biomass production for 2025 and 2030 in Louisiana is projected to be 80000000 Bone Dry Ton (BDT) and 16000000 (BDT) respectively. The findings of the study depict that Louisiana has a massive biomass supply from forest wastes for bioenergy production. Thus, the potential for Louisiana to become an influential player in the production of bio-based products from forest residues is evident. The author recommends that future research can use Geographic Information Systems (GIS) to create maps displaying the potential locations and utilization centers of forest wastes for bioenergy production in the state.

Forest carbon sink in the U.S. (1870–2012) driven by substitution of forest ecosystem service flows

Understanding the dynamics behind forest transitions, i.e., shifts from deforestation to forest recovery, is crucial for forest conservation and climate-change mitigation i.e., carbon (C) sequestration. We investigated the drivers of the forest transition in the United States, which was characterized by forest thickening despite surges in industrial wood extraction. We employ the concepts of Human Appropriation of Net Primary Productivity (HANPP) and Material and Energy Flow Analysis (MEFA) to quantitatively assess changes in major provisioning ecosystem services demanded from forests, i.e., industrial wood (comprising biomass used in products such as paper and pulp), grazing, and fuelwood, and analyse substitution processes from 1870-2012 at regional, sectoral, and national scales. The share of industrial wood in total annual forest biomass harvest increased from 23% to 84% over the time-period, while fuelwood and biomass grazed declined from 63% to 13%, and 14% to 3%, respectively. Reductions in demand for fuelwood and biomass grazed were enabled by shifts in feed and energy sources, consequently allowing for increases in both livestock numbers and energy use. Feed crops increased six-fold, alleviating grazing pressure on forest ecosystems, particularly in the Eastern states. Fossil fuels replaced fuelwood, especially in the residential sector. Between 1900-2012 the final energy mix increased seventeen-fold. Thus, the increase in biomass C stocks in U.S. forests was connected to substitution of forest ecosystem services with fossil fuel-based production systems, and with manifold increases in societal resource use and C dynamics. Such shifts need to be considered when assessing the positive environmental effects of forest transitions.

The Cost of Fishing on Juveniles of Finfish and Shellfish: Assessment of Economic Impacts of Trawl Juvenile by-Catch along the Coast of North Andhra Pradesh, India

A study was carried out to assess the economic value of juveniles of commercially important species of finfish and shellfish caught as by-catch by multiday commercial trawlers operated off the coast of Visakhapatnam, north Andhra Pradesh from January 2014 to December 2015. Juveniles of twenty species (four species of cephalopods and sixteen species of finfish) were found to dominate the trawl by-catch. The landed juveniles of these 20 species formed 12,757.16 t and 286.86 million numbers per year and their contribution to the total landings of these species in trawl by-catch were 55.30% by weight and 57.03% by numbers. The highest percentage of quantities of juveniles (biomass) was found in trawl by-catch in the months of August and July in, 2014 and 2015 respectively. Among the juveniles, ribbonfish (Trichiurus lepturus) and goatfish (Upeneus vittatus) dominated, contributing together, on an average 11.60% by weight and 33.68% by numbers respectively. Using the bio-economic model, it was estimated that if the juveniles were allowed to grow up to length at first maturity; total annual economic gain would have been Rs. 273.21 crores (42.03 million USD) with biomass gain of 44,493.02 t per annum. The estimated total annual biomass would have increased 3.46 times with an increase in revenue by 4.20 times. Annual average loss due to fishing of juveniles was estimated to be Rs. 209.62 crores (32.25 million USD). The results of the present study suggested that sustainable harvest of these resources would have yielded maximum economic return to the fishers. With the help of stakeholders using a participatory approach, management measures such as increase of cod end mesh size of trawl to 40 mm from the present mesh size of 10–12 mm, use of square mesh for trawl cod ends, fishing effort restriction and awareness campaign on the detrimental impacts of catching juveniles needs to be implemented at the earliest for avoiding growth overfishing.

Timing of drought in the growing season and strong legacy effects determine the annual productivity of temperate grasses in a changing climate

Abstract. The frequency of extreme weather events, such as droughts, is assumed to increase and lead to alterations in ecosystem productivity and thus the terrestrial carbon cycle. Although grasslands typically show reduced productivity in response to drought, the effects of drought on grassland productivity have been shown to vary strongly. Here we tested, in a 2-year field experiment, if the resistance and the recovery of grasses to drought varies throughout a growing season and if the timing of the drought influences drought-induced reductions in annual aboveground net primary production (ANPP) of grasses. For the experiment we grew six temperate and perennial C3 grass species and cultivars in a field as pure stands. The grasses were cut six times during the growing season and subject to 10 week drought treatments that occurred either in the spring, the summer or the fall. Averaged across all grasses, drought-induced losses in productivity in spring were smaller (−20 % to −51 %) than in summer and fall (−77 % to −87 %). This suggests a higher resistance to drought in spring when plants are in their reproductive stage and their productivity is the highest. After the release from drought, we found no prolonged suppression in growth. In contrast, post-drought growth rates of formerly drought-stressed swards outperformed the growth rates of the control swards. The strong overcompensation in growth after the drought release resulted in relatively small overall drought-induced losses in annual ANPP that ranged from −4 % to −14 % and were not affected by the timing of the drought event. In summary, our results show that (i) the resistance in growth rates of grasses to drought varies across the season and is increased during the reproductive phenological stage when growth rates are highest; (ii) that the positive legacy effects of drought indicate a high recovery potential of temperate grasses to drought; and (iii) that the high recovery can compensate for immediate drought effects on total annual biomass production to a significant extent.

Managing salmon for wildlife: Do fisheries limit salmon consumption by bears in small Alaskan streams?

Ecosystem-based management requires consideration of overlapping resource use between humans and other consumers. Pacific salmon are an important resource for both fisheries and populations of wildlife around the Pacific rim, including coastal brown bears (Ursus arctos); salmon consumption has been positively linked to bear density, body size, and reproductive rate. As a case study within the broader context of human-wildlife competition for food, we used 16-22yr of empirical data in four different salmon-bearing systems in southwestern Alaska to explore the relationship between sockeye salmon (Oncorhynchus nerka) availability and consumption by bears. We found a negative relationship between the annual biomass of salmon available to bears and the fraction of biomass consumed per fish, and a saturating relationship between salmon availability and the total annual biomass of salmon consumed by bears. Under modeled scenarios, bear consumption of salmon was predicted to increase only with dramatic (on the order of 50-100%) increases in prey availability. Even such large increases in salmon abundance were estimated to produce relatively modest increases in per capita salmon consumption by bears (2.4-4.8kg·bear-1 ·d-1 , 15-59% of the estimated daily maximum per capita intake), in part because bears did not consume salmon entirely, especially when salmon were most available. Thus, while bears catching salmon in small streams may be limited by salmon harvest in some years, current management of the systems we studied is sufficient for bear populations to reach maximum salmon consumption every 2-4yr. Consequently, allocating more salmon for brown bear conservation would unlikely result in an ecologically significant response for bears in these systems, though other ecosystem components might benefit. Our results highlight the need for documenting empirical relationships between prey abundance and consumption, particularly in systems with partial consumption, when evaluating the ecological response of managing prey resources for wildlife populations.

Sustainable Utilization of Tropical Plant Biomass for Bioproducts, Biocatalysts and Biorefienry

Burgeoning population, fastest depletion of fossil fuel resources, alarming global climate change issues are the top most challenge to be addressed for a country to prosperous in energy, environmental and economic security. Greatest attention has been paid on renewable biomass for generation of alternative fuels, bio products and fine chemicals in a sustainable manner. It has been estimated that, every year photosynthesis alone accounts for conversion of 100 billion metric tons of CO2 and H2O to cellulose and other biomass products. Hence biomass driven industry is one of the fastest growing sector, their share on global economy is increasing about 5-20%. The total world annual biomass production is estimated at 2740 quadrillion BTU’s. At present, only about 7% of the annual production of biomass is used.

Harvest index of apple and kiwifruit – how high can we go by optimising plant architecture and canopy management?

Efficiency of plant function is measured using harvest index (HI), the fraction of annual fruit dry mass yield divided by the total annual dry mass of tree. HI describes the proportion of total annual biomass allocated into harvestable sinks. The HI of mature apple trees on dwarfing rootstocks is ~60-70%, higher than HI estimates of ~40% for kiwifruit vines. In a recent physiological study using tall spindle ‘Scilate’ (EnvyTM) apple planted intensively on M.9, a mature tree fruit yield of 105 kg tree(-1) fresh weight (175 t ha(-1) at 1667 trees ha(-1)) was achieved in the 9th year from planting. Average fruit dry matter content at harvest was 16.2%, suggesting a calculated annual dry weight fruit yield of 17 kg tree(-1) (28.3 t ha(-1)) in the 9th year. This mature tree yield was produced from minimal tree structure compared with traditionally-managed trees; the main axis and branches were slender in girth, and the mean dry weight of winter prunings following harvest in the 9th year was 0.62 kg tree(-1). Hence, high fruit yields were associated with little investment in standing tree structure and prunings, implying a very high tree physiological efficiency (HI). The HI of these ‘Scilate’ trees on M.9 in the 9th year was estimated to be 0.81. We speculate that HI of late season cultivars on M.9 could reach 0.85 with further optimisation of canopy management and tree architecture using artificial spur extinction. Exploiting vine architecture and optimising canopy management of kiwifruit may similarly improve yield and fruit quality by increasing vine HI. Preliminary results on whole vine behaviour (flowering, yield and vigour) in response to canopy architectural modification using spur pruning to reduce pruning intensity of ‘Zesy002’ (SunGold®) kiwifruit indicated that spur pruning did not modify yield but reduced vine dry weight of winter prunings by 50% after a single growing cycle. Ongoing work will compare vines managed by spur pruning and replacement cane pruning to quantify budbreak, flowering, yield and fruit quality responses over successive growing cycles.

Intraspecific variation in litter palatability to macroarthropods in response to grazing and soil fertility

Abstract Clarifying the functional consequences of intraspecific trait variability in response to interacting trophic levels would provide a significant improvement in our understanding of above‐ground–below‐ground linkages. In particular, the effects of grazing on plant traits may translate into altered litter quality, with potentially important consequences for litter‐feeding decomposers. Plant and litter variability in response to grazing is expected to depend on soil fertility levels, with tolerance and defensive strategies more commonly expressed on fertile and poorer soils, respectively. However, how grazing and fertility interactively alter litter quality and palatability to detritivores has not been explored yet. We conducted a cafeteria experiment with three common millipede (Diplopoda) species feeding on leaf litter from two plant species, the grass Bromopsis erecta and the forb Potentilla verna. Each millipede was offered a binary choice between litter types produced by the same plant species, but sampled in plots with distinct herbivory and fertilization status: litter originating from grazed areas or from 1‐year sheep exclosures, both in native areas and in adjacent paddocks that received chemical N and P fertilization, as well as litter from a 25‐year sheep exclosures in the native area. We found that fertilization and herbivore exclusion interactively affected Bromopsis litter quality and palatability, whereas Potentilla was much less affected. Bromopsis litter palatability was not affected by grazing when litter was collected in native plots, except for the long‐term exclosure which led to low palatability. In contrast, and in line with our expectations, herbivory was associated with much higher palatability in fertilized plots. The changes in palatability were associated with important alterations of litter quality. Overall, our study demonstrates that intraspecific variation in litter can have profound consequences for soil functioning. It emphasizes the role of grazing as a key, but plant species‐specific factor controlling litter intraspecific variability, and its complex interaction with soil fertility level. Moreover, our results advocate for a better understanding of the response of the different organisms involved in the decomposition process, in particular litter‐feeding macro‐detritivores. We encourage future studies aiming at disentangling the various and complex relationships between above‐ground processes such as herbivory and soil functioning.

Effects of Grazing Abandoned Grassland on Herbage Production and Utilization, and Sheep Preference and Performance

Large areas of farmland are abandoned in Norway, which for various reasons are regarded as undesirable. Loss of farmland may have negative implications for biodiversity and ecosystem function and food production potential. The objectives of this study were to assess forage mass production and utilization, botanical composition, lamb performance, and grazing distribution pattern when reintroducing livestock grazing to an abandoned grassland. The study area was located in Central Norway, unmanaged for 12 years. Sheep grazed the area for 10 weeks in 2013 and four weeks in spring and autumn, respectively, in 2014 and 2015. During the summer of 2014 and 2015, the area was subjected to the following three replicated treatments: 1) No grazing, 2) grazing with heifers, and 3) grazing with ewes and their offspring. The stocking rate was similar in the grazed treatments. Forage biomass production and animal intake were estimated using grazing exclosure cages and botanical composition by visual assessment. Effect on lamb performance was evaluated by live weight gain and slaughter traits in sheep subjected to three treatments: 1) Common farm procedure with summer range pasturing, 2) spring grazing period extended by one month on the abandoned grassland before summer range pasturing, and 3) spring and summer grazing on the abandoned grassland. Grazing distribution patterns were studied using GPS position collars on ewes. Total annual biomass production was on average 72% higher with summer grazing than without. Annual consumption and utilization was on average 218 g DM/m2 and 70% when summer grazed, and 25 g DM/m2 and 18% without grazing, respectively. Botanical composition did not differ between treatments. Live weight gain was higher in lambs subjected to an extended spring grazing period (255 g/d) compared to common farm practice (228 g/d) and spring and summer grazing on the abandoned grassland (203 g/d), and carcass value was 14% higher in lambs on extended spring grazing compared to common farm practice. In autumn, sheep preferred to graze areas grazed by sheep during summer. Re-introduction of grazing stimulated forage production, and extended spring grazing improved performance in lambs. This study has quantified the value of abandoned grassland as a

Net ecosystem productivity and carbon dynamics of the traditionally managed Imperata grasslands of North East India

There have been few comprehensive descriptions of how fire management and harvesting affect the carbon dynamics of grasslands. Grasslands dominated by the invasive weed Imperata cylindrica are considered as environmental threats causing low land productivity throughout the moist tropical regions in Asia. Imperata grasslands in North East India are unique in that they are traditionally managed and culturally important in the rural landscapes. Given the importance of fire in the management of Imperata grassland, we aimed to assess (i) the seasonal pattern of biomass production, (ii) the eventual pathways for the produced biomass, partitioned between in situ decomposition, harvesting and combustion, and (iii) the effect of customary fire management on the ecosystem carbon cycle. Comparatively high biomass production was recorded during pre-monsoon (154 g m−2 month−1) and monsoon (214 g m−2 month−1) compared to the post-monsoon (91 g m−2 month−1) season, and this is attributed to nutrient return into the soil immediately after fire in February. Post fire effects might have killed roots and rhizomes leading to high belowground litter production 30–35 g m−2 during March to August. High autotrophic respiration was recorded during March–July, which was related to high belowground biomass production (35–70 g m−2) during that time. Burning removed all the surface litter in March and this appeared to hinder surface decomposition and result in low heterotrophic respiration. Annual total biomass carbon production was estimated at 886 g C m−2. Annual harvest of biomass (estimated at 577 g C m−2) was the major pathway for carbon fluxes from the system. Net ecosystem production (NEP) of Imperata grassland was estimated at 91 g C m−2 yr−1 indicating that these grasslands are a net sink of CO2, although this is greatly influenced by weather and fire management.

Mechanisms preventing a decrease in phytoplankton biomass after phosphorus reductions in a German drinking water reservoir—results from more than 50 years of observation

Abstract To counteract the severe consequences of eutrophication on water quality and ecosystem health, nutrient inputs have been reduced in many lakes and reservoirs during the last decades. Contrary to expectations, in some lakes phytoplankton biomass did not decrease in response to oligotrophication (nutrient reduction). The underlying mechanisms preventing a decrease in biomass in these lakes are the subject of ongoing discussion. We used a hitherto unpublished long‐term data set ranging from 1961 until 2016 from a German drinking water reservoir (Rappbode Reservoir) to investigate the underlying mechanisms preventing a decrease in biomass. Total phosphorus (TP) concentrations in the Rappbode Reservoir dropped abruptly in 1990 from 0.163 to 0.027 mg/L within three consecutive years, as a result of banning phosphate‐containing detergents. Despite substantial reductions in TP, total annual phytoplankton biomass did not decline in the long‐run, and therefore, the yield of total phytoplankton biomass per unit phosphorus largely increased. Regression analysis revealed a positive association between the yield and potentially phagotrophic mixotrophs (R2 = .465, p &lt; .001). We infer that by ingesting bacteria, mixotrophic species were capable of exploiting additional P sources that are not accessible to obligate autotrophic phytoplankton, eventually preventing a decrease in algal biomass after TP reductions. Long‐term epilimnetic phosphorus concentrations during the winter mixing period decreased to a greater degree than summer phosphorus concentrations. Apparently, TP losses over the season were less intense. Spring diatom biomass also markedly decreased after oligotrophication. In fact, spring diatom biomass was positively related to the TP loss over the season suggesting diatoms play an important role in P reduction. However, this intraannual P processing was not the primary factor when focusing on the average yearly yield, which remained to be fully explained by mixotrophs. Our study demonstrates this ecosystem's ability to compensate for changes in resource availability through changes in phytoplankton community composition and functional strategies. We conclude that an increase in mixotrophy and the ability to make bacterial phosphorus available for phytoplankters were the main factors that allowed the phytoplankton community of the Rappbode Reservoir to adapt to lower nutrient levels without a loss in total biomass.

Ozone risk assessment is affected by nutrient availability: Evidence from a simulation experiment under free air controlled exposure (FACE)

Assessing ozone (O3) risk to vegetation is crucial for informing policy making. Soil nitrogen (N) and phosphorus (P) availability could change stomatal conductance which is the main driver of O3 uptake into a leaf. In addition, the availability of N and P could influence photosynthesis and growth. We thus postulated that the sensitivity of plants to O3 may be changed by the levels of N and P in the soil. In this study, a sensitive poplar clone (Oxford) was subject to two N levels (N0, 0 kg N ha−1; N80, 80 kg N ha−1), three P levels (P0, 0 kg P ha−1; P40, 40 kg P ha−1; P80, 80 kg P ha−1) and three levels of O3 exposure (ambient concentration, AA; 1.5 × AA; 2.0 × AA) for a whole growing season in an O3 free air controlled exposure (FACE) facility. Flux-based (POD0 to 6) and exposure-based (W126 and AOT40) dose-response relationships were fitted and critical levels (CLs) were estimated for a 5% decrease of total annual biomass. It was found that N and P availability modified the dose-response relationships of biomass responses to O3. Overall, the N supply decreased the O3 CLs i.e. increased the sensitivity of poplar to O3. Phosphorus alleviated the O3-caused biomass loss and increased the CL. However, such mitigation effects of P were found only in low N and not in high N conditions. In each nutritional treatment, similar performance was found between flux-based and exposure-based indices. However, the flux-based approach was superior, as compared to exposure indices, to explain the biomass reduction when all nutritional treatments were pooled together. The best O3 metric for risk assessments was POD4, with 4.6 mmol m−2 POD4 as a suitable CL for Oxford poplars grown under various soil N and P conditions.

Study of Paulownia's Biomass Production in Mérida (Badajoz), Southwestern Spain

Fast-growing forest species have become an alternative to take into account for irrigated land with lower profit margins. The objective of this project is to know the adaptation and biomass yields of the Paulownia crop for biomass and timber production, in the irrigated area of the Guadiana River 'Vegas Bajas' in Extremadura Region, (SPAIN). In 2012, two plots with 4 different Paulownia clones were planted (112, COT2, L1 and X1). One plot has been destined to timber production (T), with a 10-year rotation, grown at 4 by 4m spacing, and the other plot has been destined to biomass production (B), with a 3-year rotation, grown at 3 by 2m spacing. In February 2016, the first rotation stand of the biomass (B) plot was harvested. Clone X1 has showed a significantly lower performance in terms of dry matter production and growth, whilst among the other 3 clones, no significant differences were observed. The total production of the biomass plot was 24280.1kg dry matter ha-1. Average annual total biomass yield was 8093.4 Kg ms ha-1 for plot (B).

Exploitable biomass status and potential of the Southeastern Anatolia Region, Turkey

ABSTRACTIn this study, the exploitable biomass potential of nine provinces located in the Southeastern Anatolia region of Turkey was investigated. Animal- and vegetal-derived biomasses were taken into consideration in the analyses. The animal-derived biomass was handled as poultry, small ruminants, and cattle. The vegetal-derived biomass was accounted as field, garden, and vegetable crops. The contribution of each species on the biomass energy potential was studied. The available animal and vegetal residues in the region were estimated to be, respectively, equal to 6.2% and 9.4% of the corresponding residual amount in Turkey. The annual total biomass potential of the region was found to be approximately 83.4 PJ which could meet 15.7% energy demand of the region.

Biomass from fruit trees for combined energy and food production

In the EU-28, the annual fruit tree production is about 1.29 million ha. In Germany pome and stone fruit are cultivated on 44,744 ha (apples 31,334 ha, 3855 ha plums, 1925 ha pears). This generates not only food, but also abundant amounts of biomass when orchards are cleared at the end of their life span. While the pruning wood from fruit trees is already partly utilized, clearance wood has not been studied in detail for its energetic potential for direct combustion. The main aim was to evaluate the woody residues potential from a fruit tree production area of 676 ha and if that were suitable for direct combustion in a regional context. The mean biomass yield of clearance wood from fruit orchards in the study is 10.6 Mg*ha−1, with a theoretical energy content of 53,172 kWh*ha−1. With a total annual biomass yield of 357 Mg in the studied area, an oil equivalent of over 150,000 L could be substituted each year by clearance wood from fruit orchards. Utilization of clearance wood as an abundant biomass source is a promising concept for a sustainable energy supply on a local to regional scale and without interfering in food production or causing land allocation issues.

Energy supply modelling of a low-CO2 emitting energy system: Case study of a Danish municipality

Municipal activities play an important role in national and global CO2-emission reduction efforts, with Nordic countries at the forefront thanks to their energy planning tradition and high penetration of renewable energy sources. In this work, we present a case study of the Danish municipality of Sønderborg, whose aim is to reach zero net CO2 emissions by 2029. Sønderborg has an official strategic plan towards 2029, which we compared with four alternative scenarios to investigate how the municipality could approach its target in the most energy-efficient and cost-effective way while simultaneously keeping biomass and waste consumption close to the limits of the locally available residual resources.We modelled all sectors of the energy system on the municipal scale, applying a broad range of energy conversion technologies, including advanced biomass conversion technologies and reversible electrolysis. We constructed five scenarios, each representing a different energy mix for Sønderborg’s energy system in 2029. We modelled these scenarios using the mixed-integer linear optimization tool Sifre. We compared the results for the five scenarios using four indicators: annual total system cost, total energy system efficiency, annual net system CO2 emissions and total annual biomass consumption.The results show that scenarios with a high degree of electrification perform better on the selected indicators than scenarios with a high degree of biomass utilization. Moreover, the incorporation of advanced conversion technologies such as electrolysis, fuel cells and methanol production further reduces both the total system cost and net CO2 of the highly electrified energy system. Our sensitivity analysis demonstrates that scenarios with a low biomass consumption and a high degree of electrification are less dependent on changes in energy prices.We conclude that in order to achieve their CO2 emission goals in the most energy-efficient, cost-effective and sustainable way, municipalities similar to Sønderborg should compare a wide range of energy system configurations, for example, scenarios with a high degree of electrification and a limited biomass use.

Modelling the comparative growth, water use and productivity of the perennial legumes, tedera (Bituminaria bituminosa var. albomarginata) and lucerne (Medicago sativa) in dryland mixed farming systems

Tedera (Bituminaria bituminosa var. albomarginata) has been proposed as an alternative perennial forage legume to lucerne in the mixed farming zone of Australia. Simulation of growth and production of tedera would be a useful tool for assessing its integration into Australian farming systems and agronomic and management options. This paper describes the development and testing of a model of the growth and development of tedera in Agricultural Production Systems Simulator (APSIM). The existing APSIM-Lucerne was modified to develop APSIM-Tedera. The key physiological parameters for tedera were obtained from the literature or by measuring and comparing the phenology and growth characteristics of tedera and lucerne in glasshouse experiments and partially from field experiments. The model was tested using data from a diverse range of soil and climatic conditions. Using the modelling approach, the production of tedera and lucerne was also assessed with long-term (1951–2015) weather data at Arthur River, Western Australia. Biomass simulations of tedera (n = 26, observed mean = 510 kg dry mass ha–1) explained 66% of the observed variation in field experiments (root mean square deviation = 212 kg dry mass ha–1). Long-term simulations of a 4-year pasture phase showed that more total annual biomass (5600 kg ha–1) would be obtained from lucerne than tedera if the pasture forage was harvested four times a year. Less biomass (400 kg ha–1) was also simulated for tedera in summer under this management. When the pasture forage was harvested when biomass was more than 2000 kg ha–1, tedera and lucerne produced similar accumulated biomass in the second (8000 kg ha–1), third (12 000 kg ha–1) and fourth (15 000 kg ha–1) years, but much less in the first 2 years for tedera. The model can be used for assessing tedera production, agronomic and management options in the Mediterranean climate of Australia. The present preliminary study indicates that tedera is not as effective as lucerne for total biomass production, but it may provide useful feed in situations where the summer-autumn feed gap is a major constraint to production. Further research is also necessary to determine the potential role of tedera in areas where lucerne is not well adapted.

An Assessment on Economic Impact of Growth Over Fishing of Commercially Important Marine Ariids Along Mumbai, Northwest Coast of India.

The economic assessment on juvenile landings of four dominant marine catfishes at New Ferry Wharf (NFW) landing centre, Mumbai, Northwest coast of India was carried out during January to December, 2013. The dominant catfishes viz. Nemapteryx caelata (19.7 %), Plicofollis dussumieri (21.5 %), P. tenuispinis (24.8 %) and Osteogeneiosus militaris (27.5 %) together contributing 93% of total marine catfish landings of the state. Among four species, the juvenile landings of N. caelata contribute maximum(93.17 %) followed by P. dussumieri (57.14 %), O. militaris (36.11 %) and P. tenuispinis (21.43 %) with the maximum landing during November to March . The bioeconomic model reveals that if juveniles are allowed to grow up to length at first maturity (Lm); an estimated total annual economic gain will be Rs. 13.15 crores with an estimated biomass gain of 1222 t per annum. The estimated total annual biomass is increased by 2.07 times with an increase in additional revenue by 3.7 times would have been realised. The results of present study suggest that sustainable harvest of these resources would have been yielded maximum economic return to the fishers. With the help of stakeholders participatory approach, management measures such as strict mesh size regulation, effort restriction on bottom trawl up to 50 m depth and awareness campign on catching juveniles and adult in particulat to the oral incubated male ariids, would have been implemented during November to March to avoid growth over fishing.