PURPOSE: Livestock already use most global agricultural land, whereas the demand for animal-source food (ASF) is expected to increase. To address the contribution of livestock to global food supply, ...we need a measure for land use efficiency of livestock systems. METHODS: Existing measures capture different aspects of the debate about land use efficiency of livestock systems, such as plant productivity and the efficiency of converting feed, especially human-inedible feed, into animal products. So far, the suitability of land for cultivation of food crops has not been accounted for. Our land use ratio (LUR) includes all above-mentioned aspects and yields a realistic insight into land use efficiency of livestock systems. LUR is defined as the maximum amount of human-digestible protein (HDP) derived from food crops on all land used to cultivate feed required to produce 1Â kg ASF over the amount of HDP in that 1Â kg ASF. We illustrated our concept for three case systems. RESULTS AND DISCUSSION: The LUR for the case of laying hens equaled 2.08, implying that land required to produce 1Â kg HDP from laying hens could directly yield 2.08Â kg HDP from human food crops. For dairy cows, the LUR was 2.10 when kept on sandy soils and 0.67 when kept on peat soils. The LUR for dairy cows on peat soils was lower compared to cows on sandy soils because land used to grow grass and grass silage for cows on peats was unsuitable for direct production of food crops. A LUR <1.0 is considered efficient in terms of global food supply and implies that animals produce more HDP per square metre than crops. CONCLUSIONS: Values <1.0 demonstrate that livestock produce HDP more efficiently than crops. Such livestock systems (with a LURâ
Objective: This study was conducted to provide models to accurately predict nitrogen (N) and phosphorus (P) excretion of dairy cows on smallholder farms in Indonesia based on readily available farm ...data.Methods: The generic model in this study is based on the principles of the Lucas equation, describing the relation between dry matter intake (DMI) and faecal N excretion to predict the quantity of faecal N (QFN). Excretion of urinary N and faecal P were calculated based on National Research Council recommendations for dairy cows. A farm survey was conducted to collect input parameters for the models. The data set was used to calibrate the model to predict QFN for the specific case. The model was validated by comparing the predicted quantity of faecal N with the actual quantity of faecal N (QFNACT) based on measurements, and the calibrated model was compared to the Lucas equation. The models were used to predict N and P excretion of all 144 dairy cows in the data set.Results: Our estimate of true N digestibility equalled the standard value of 92% in the original Lucas equation, whereas our estimate of metabolic faecal N was –0.60 g/100 g DMI, with the standard value being –0.61 g/100 g DMI. Results of the model validation showed that the R2 was 0.63, the MAE was 15 g/animal/d (17% from QFNACT), and the RMSE was 20 g/animal/d (22% from QFNACT). We predicted that the total N excretion of dairy cows in Indonesia was on average 197 g/animal/d, whereas P excretion was on average 56 g/animal/d.Conclusion: The proposed models can be used with reasonable accuracy to predict N and P excretion of dairy cattle on smallholder farms in Indonesia, which can contribute to improving manure management and reduce environmental issues related to nutrient losses.
•Global climate mitigation targets and local agricultural policies must be internally consistent.•We project the emission intensity of agriculture at global, regional and national levels.•Food ...production and climate mitigation require systemic changes beyond technological fixes.•Cross-scale thinking is needed for the operationalization of the Sustainable Development Goals.
The Sustainable Development Goals (SDGs) imply country-led implementation. Yet, their achievement depends on sustainability targets compatible across different sectors and scales. Our study examines how the GHG emission intensity of agriculture (EIA) should evolve globally, regionally (Western Europe) and nationally (The Netherlands) under different socioeconomic pathways, so that two major aims of SDGs 2 and 13 (i.e. sufficient food production and climate change mitigation) are achieved simultaneously. Results show that, by 2050, relative to 2010 values, EIA should decrease at all three levels when measured on a product basis (GHG emissions per ton dry matter) and on a land basis (GHG emissions per ha). This indicates that, globally, agriculture should be intensified per unit area, while in Western Europe and even more so in the Netherlands additional emission reductions require increased production efficiency and lower production volumes. Projected reductions in methane and nitrous oxide emissions from enteric fermentation, manure management and fertilizer application in Dutch agriculture are much higher than what would be achieved through the extrapolation of current trends. Given the high costs of increasing production efficiency further, our analysis indicates the need for significantly more ambitious policy targets and systemic changes, including reduced consumption of animal-sourced food. Besides shedding light on the interaction between climate and agricultural strategies, our analysis illustrates the application of cross-scale thinking in the operationalization of the SDG agenda and underscores the need for concerted action amongst countries.
Shortening or omitting the dry period of dairy cows improves metabolic health in early lactation and reduces management transitions for dairy cows. The success of implementation of these strategies ...depends on their impact on milk yield and farm profitability. Insight in these impacts is valuable for informed decision-making by farmers. The aim of this study was to investigate how shortening or omitting the dry period of dairy cows affects production and cash flows at the herd level, and greenhouse gas emissions per unit of milk, using a dynamic stochastic simulation model. The effects of dry period length on milk yield and calving interval assumed in this model were derived from actual performance of commercial dairy cows over multiple lactations. The model simulated lactations, and calving and culling events of individual cows for herds of 100 cows. Herds were simulated for 5 years with a dry period of 56 (conventional), 28 or 0 days (n = 50 herds each). Partial cash flows were computed from revenues from sold milk, calves, and culled cows, and costs from feed and rearing youngstock. Greenhouse gas emissions were computed using a life cycle approach. A dry period of 28 days reduced milk production of the herd by 3.0% in years 2 through 5, compared with a dry period of 56 days. A dry period of 0 days reduced milk production by 3.5% in years 3 through 5, after a dip in milk production of 6.9% in year 2. On average, dry periods of 28 and 0 days reduced partial cash flows by €1,249 and €1,632 per herd per year, and increased greenhouse gas emissions by 0.7% and 0.5%, respectively. Considering the potential for enhancing cow welfare, these negative impacts of shortening or omitting the dry period seem justifiable, and they might even be offset by improved health.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Pork is one of the most globally eaten meats and the pig production chain contributes significantly to the water footprint of livestock production. However, very little knowledge is available about ...the on-farm factors that influence freshwater use in the pig production chain. An experiment was conducted to quantify the effect of three different washing treatments on freshwater use, bacterial levels (total bacterial counts; TBC), Enterobacteriaceae and Staphylococcus and cleaning time in washing of pens for weaning pigs. Three weaner rooms were selected with each room having 10 pens and a capacity to hold up to 14 pigs each. Pigs were weaned and kept in the pens for 7 weeks. Finally, the pens were cleaned before the next batch of pigs moved in. The washing treatments used were power washing and disinfection (WASH); presoaking followed by power washing and disinfection (SOAK), and presoaking followed by detergent, power washing and disinfection (SOAK + DETER). A water meter was used to collect water use data and swab samples were taken to determine the bacterial levels. The results showed that there was no overall effect of washing treatments on water use. However, there was an effect of treatment on the washing time (p<0.01) with SOAK and SOAK+DETER reducing the washing time per pen by 2.3 minutes (14%) and 4.2 minutes (27%) compared to WASH. Nonetheless, there was an effect of sampling time (before or after washing) (p<0.001) on the levels of TBC and Staphylococcus, but no effect was seen on Enterobacteriaceae levels. Thus, the washing treatments used in this study had no effect on the water use of the pork production chain. Although there was no difference in both water use and bacterial load, from a producer perspective, presoaking and detergent use can save time and labour costs, so this would be the preferred option.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
Carbon sequestration in grasslands has been proposed as an important means to offset greenhouse gas emissions from ruminant systems. To understand the potential and limitations of this ...strategy, we need to acknowledge that soil carbon sequestration is a time-limited benefit, and there are intrinsic differences between short- and long-lived greenhouse gases. Here, our analysis shows that one tonne of carbon sequestrated can offset radiative forcing of a continuous emission of 0.99 kg methane or 0.1 kg nitrous oxide per year over 100 years. About 135 gigatonnes of carbon is required to offset the continuous methane and nitrous oxide emissions from ruminant sector worldwide, nearly twice the current global carbon stock in managed grasslands. For various regions, grassland carbon stocks would need to increase by approximately 25% − 2,000%, indicating that solely relying on carbon sequestration in grasslands to offset warming effect of emissions from current ruminant systems is not feasible.
Soybean production has a crucial role in the development of Brazilian agriculture and recently became the most important commodity in Brazilian agribusiness. Various soybean farming systems exist, ...which are claimed to differ in terms of sustainability performance. In this regard, evaluation of environmental, economic, and social performance of different soybean farming systems in Brazil, by consideration of variability in input parameters, is critically needed. In this context, we evaluated a number of environmental, economic, and social issues for the two main soybean farming systems in southern Brazil, the conventional system, which produces genetically modified (GM) or non-genetically modified (non-GM) soybeans, and the organic system. Data were collected for 2012 from three sources: soybean farms in Paraná, Brazil (15 GM, 15 non-GM, and 15 organic farms), the Brazilian Enterprise for Agricultural Research (EMBRAPA), and expert elicitation. Monte Carlo simulation was used to account for the variation in input parameters. Five sustainability issues were evaluated in this study: global warming, land occupation, primary energy use, profitability, and employment. Results revealed that, compared with the GM and non-GM systems, organic systems had a higher probability (77%) to have a lower global warming potential. Land occupation was higher and energy use was lower for organic systems than for the GM and non-GM systems at every level of probability. Concerning profitability, organic systems had a higher probability (60%) to have higher profitability compared with GM and non-GM production, and employment was higher for organic systems at every level of probability. Overall, simulation results of this study illustrated the relatively high level of variation in the environmental, economic, and social performance of organic soybean farming systems. This study shows that accounting for variability in key system parameters provides not only insight in the most likely outcomes, but also in the robustness of system performance.
•Environmental, economic, and social performance of soybean systems evaluated.•Stochastic model applied to give insight into a range of outcomes.•The model provides more comprehensive and robust information to policy makers.•Differences between systems are not only structural, but also dependant on inputs.
PURPOSE: Production of feed is an important contributor to life cycle greenhouse gas emissions, or carbon footprints (CFPs), of livestock products. Consequences of methodological choices and data ...sensitivity on CFPs of feed ingredients were explored to improve comparison and interpretation of CFP studies. Methods and data for emissions from cultivation and processing, land use (LU), and land use change (LUC) were analyzed. METHOD: For six ingredients (maize, wheat, palm kernel expeller, rapeseed meal, soybean meal, and beet pulp), CFPs resulting from a single change in methods and data were compared with a reference CFP, i.e., based on IPCC Tier 1 methods, and data from literature. RESULTS AND DISCUSSION: Results show that using more detailed methods to compute N₂O emissions from cultivation hardly affected reference CFPs, except for methods to determine Formula: see text leaching (contributing to indirect N₂O emissions) in which the influence is about −7 to +12 %. Overall, CFPs appeared most sensitive to changes in crop yield and applied synthetic fertilizer N. The inclusion of LULUC emissions can change CFPs considerably, i.e., up to 877 %. The level of LUC emissions per feed ingredient highly depends on the method chosen, as well as on assumptions on area of LUC, C stock levels (mainly aboveground C and soil C), and amortization period. CONCLUSIONS: We concluded that variability in methods and data can significantly affect CFPs of feed ingredients and hence CFPs of livestock products. Transparency in methods and data is therefore required. For harmonization, focus should be on methods to calculate Formula: see text leaching and emissions from LULUC. It is important to consider LUC in CFP studies of food, feed, and bioenergy products.
In many places on earth, livestock and feed production are decoupled, as feed is grown in one region and fed to livestock in another. This disrupts nutrient cycles by depleting resources in feed ...producing regions and accumulating resources in livestock areas, which leads to environmental degradation. One solution is to recouple livestock and feed production at a more local level, which enhances nutrient circularity. Recoupling livestock and feed production creates a natural ceiling for livestock numbers based on the feed producing capacity of a region. In this study we assess the consequences of recoupling livestock and feed production (i.e., by avoiding the import and export of animal feed) on ammonia and greenhouse gas (GHG) emissions, with and without feed-food competition. To this end, we used FOODSOM, an agro-ecological food system optimisation model representing the Dutch food system in this study. The Netherlands is one example of a region with high livestock densities and resource accumulation. We found that recoupling decreased livestock numbers (beef cattle: −100 %; dairy cattle: −29 %; broiler chickens: −57 %; laying hens: −67 %; pigs: −62 %; sheep −100 %) and animal-sourced food exports (−59 %) while still meeting the current human diet in the Netherlands. Consequently, ammonia emissions and GHG emissions decreased, and the nitrogen use efficiency increased from 31 % to 38 % at the food systems level. Recoupling alone was almost sufficient to meet national emission targets. Fully meeting these targets required further small changes in livestock numbers. Avoiding feed-food competition decreased livestock productivity and GHG emissions but did not improve nitrogen use efficiency. Total meat production could not meet domestic consumption levels while avoiding feed-food competition, and resulted in additional beef cattle. We show that recoupling livestock and feed production is a promising next step to enhance circularity while decreasing agricultures environmental impact.
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•Consequences of recoupling livestock and feed production in the Netherlands were assessed.•Livestock numbers and animal-sourced food exports decreased in the Netherlands.•The current Dutch diet can be met when recoupling livestock and feed production.•National nitrogen and greenhouse gas emission targets were not met by only recoupling.•Avoiding feed-food competition without dietary change increased beef cattle numbers.
Grazing systems emit greenhouse gases, which can, under specific agro-ecological conditions, be partly or entirely offset by soil carbon sequestration. However, any sequestration is time-limited, ...reversible, and at a global level outweighed by emissions from grazing systems. Thus, grazing systems are globally a net contributor to climate change and the time scale of key processes needs to be factored into any mitigation efforts. Failing to do so leads to unrealistic expectations of soil carbon management in grazing systems as a mitigation strategy. Protecting the large carbon stocks in grazing lands is also essential in order to avoid further climate change from additional CO
2
release. Despite the time-limited and reversible nature of soil carbon sequestration in grazing lands, sequestration should be promoted in cases where it delivers environmental and agronomic benefits as well as for its potential, particularly on degraded land, to increase the feasibility of limiting global warming to less than 2 or preferably 1.5 °C. Some peer-reviewed sequestration estimates are of a similar order of magnitude to other food systems mitigation options over a 10–20 years period, such as reducing food loss and waste by 15% or aligning diets with current health related dietary-recommendations. However, caution should be applied to such comparisons since mitigation estimates are associated with large uncertainties and will ultimately depend on the economic cost-benefit relation, feasibility of implementation and time frame considered.
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