Reduced GHG emissions due to compost production and compost use in Egypt

Composting has been acknowledged as an emission reduction methodology by the UNFCCC. The emission reduction reached by a composting project is determined by comparing the composting scenario with the applicable baseline scenario. The objective of this study was on the one hand to clarify the emission reduction methodology of a composting facility in Egypt and on the other hand to extend this methodology with an example to illustrate the effect of compost use on greenhouse gas emissions. In this study, the emissions in a scenario where compost originating from a compost facility near Alexandria is used on a citrus farm in Egypt, were compared with a hypothetical baseline scenario where organic waste is not recycled and chemical fertilizer is used on the farm. The results show that the composting scenario causes significant lower emissions than the baseline scenario. This is mainly due to the avoidance of methane emissions from organic waste dumping, but also emissions due to chemical fertilizer production are avoided. The third reason for lower emission in the composting scenario is soil carbon sequestration. The composting scenario on the other hand also causes extra emissions due the transportation of biomass and fuel use for windrow turning. Although not showed in this study, it must be mentioned that compost has other beneficial effects, like improving soil fertility, improving the buffering capacity and reducing the risk for pathogens

Carbon sequestration potential of reclaimed desert soils in Egypt

The objective of this study was to investigate the carbon storage potential of reclaimed soils under organic management. Agricultural soils are often mentioned as a potential carbon sink. However, until now the UNFCCC (United Nations Framework Convention on Climate Change) doesn’t issue certified emission reductions (CERs) for carbon sequestration in soils. This research focuses on carbon stock development of reclaimed desert soils in Egypt. The research was conducted on two farms owned by Sekem, one of which located 60 km north-east of Cairo, and the other one in the Sinai desert. Five agricultural fields of different ages (1-30 years in use) were selected and compared with the surrounding desert. In every field, representative soil samples were collected from 3 line transects, each consisting of 5 sample points. The samples were taken at three horizons; 0-10 cm, 10-30 cm and 30-50 cm, and tested for differences in physical (soil texture and bulk density), and chemical (acidity, salinity and organic carbon levels) properties. The results show that reclaimed desert soils under organic management sequester carbon very rapidly in the first few years after land reclamation, but that this rate decreases after several years, following a logarithmic curve. The increase in soil carbon was first measured in the top soil (0-10 cm) and then in deeper soil layers. The bulk density of the top soil layer decreased at the same time. The results show that in 30 years of organic agriculture, the soil carbon stock increased from 3,9 to 28,8-31,8 tons C/ha, a raise of ca 24,9-27,9 t C/ha. On average, the soil stored 0,9 t C/ha/y in these 30 years. Thus, an atmospheric CO2 reduction of 3,2 tons CO2-equivalents per ha and year had taken place. It is rather unlikely that soil carbon sequestration will be approved by the UNFCCC on the short term as a methodology to mitigate the greenhouse effect. This is due to the fact that the permanency of carbon sequestration in soils is questionable. Issuing carbon credits to farmers in for instance underdeveloped dry land regions that sequester carbon in the soil could function as an incentive for sustainable farming. High organic matter levels reduce irrigation water needs and improve soil fertility, which may be helpful for combating droughts and food scarcity

Carbon footprint and driving forces of saline agriculture in coastally reclaimed areas of eastern China: a survey of four staple crops

Carbon emissions have always been a key issue in agricultural production. Because of the specific natural factors in the soil of saline agriculture, there are distinctive characteristics in saline agricultural production as compared with traditional agricultural zones. Here, we have adopted the theory of life cycle assessment, and employed the Intergovernmental Panel on Climate Change (IPCC) greenhouse gas (GHG) field calculation to estimate the GHG emissions, derived from the staple crop productions (i.e., barley, wheat, corn and rice). In addition, our study further analyzed the main driving forces of carbon emissions, and proposed some effective measures to reduce them. Our results have showed that: (1) Carbon footprint from the four crops in the study area varies from 0.63 to 0.77 kg CO2 eq•kg-1, which is higher than that from traditional agriculture; (2) GHG emissions from Fertilizer-Nitrogen (N) manufacture and inorganic N application have contributed to the greatest percentage of carbon footprint. Compared with traditional agricultural zones, fertilizer-N application and paddy irrigation involved with crop productions have overall greater contributions to carbon footprint; (3) Carbon emissions from saline agriculture can be reduced significantly by planting-breeding combination to reduce the amount of N fertilizer application, improving the traditional rotation system, and developing water-saving agriculture and ecological agriculture

Urban wastewater reuse for citrus irrigation in Algarve, Portugal—Environmental benefits and carbon fluxes

Water scarcity is increasing in the Mediterranean and alternative sources of water are needed to meet food production needs, protect the environment and reduce the effects of climate change. Currently, many urban wastewater treatment plants (WWTP) produce high volumes of treated effluents which can be an alternative source of water for agriculture irrigation, since they fulfill the quality requirements for crops and the environment. This work analyzed the quantity and quality of a treated effluent produced by an urban WWTP in Algarve, and the environmental benefits of its use on the irrigation of a citrus orchard, as an alternative to groundwater. Carbon dioxide emissions related to orange production were quantified and the orchard’s potential to sequester CO2 was estimated. The reuse of this urban wastewater is revealed to be technologically feasible and environmentally advantageous, avoiding the overexploitation of the local aquifer and preventing the eutrophication of aquatic ecosystems, contributing to the improvement of soil characteristics and decreasing the carbon emissions in orange production. Furthermore, it was found that during the five-month experimental period, the citrus orchard sequestered 87.5% of the CO2e emitted by WWTP in the effluent treatment, converting 72,623 kg of sequestered CO2 into orange biomassinfo:eu-repo/semantics/publishedVersio

Municipal Wastewater Irrigation for Rice Cultivation

In scene of worrisome water shortage, municipal wastewater has been gradually accepted as an alternative water resource containing important nutrients for irrigation. Rice cultivation, which is one of the main crops feeding global population and requires plenty of water for its effective growth, has been often irrigated by municipal wastewater in many countries. While irrigation of municipal wastewater for rice cultivation must bring benefits for farmers mainly by increased yield with less amount of fertilizers, it also has potential to cause drawbacks to human health and the environment. This chapter discusses about these aspects based on scientific works and practical experiences of municipal wastewater irrigation for rice production as well as the introduction of our concept to cultivate rice for animal feeding with irrigation of treated wastewater, which can contribute to resource circulation between urban and rural areas. The feasibility study under this concept has demonstrated that the target value of rice yield can be achieved and protein‐rich rice preferable for animal feed can be harvested with irrigation of properly treated municipal wastewater

Carbon benefits of wolfberry plantation on secondary saline land in Jingtai oasis, Gansu:A case study on application of the CBP model

The largest global source of anthropogenic CO2 emissions comes from the burning of fossil fuel and approximately 30% of total net emissions come from land use and land use change. Forestation and reforestation are regarded worldwide as effective options of sequestering carbon to mitigate climate change with relatively low costs compared with industrial greenhouse gas (GHG) emission reduction efforts. Cash trees with a steady augmentation in size are recognized as a multiple-beneficial solution to climate change in China. The reporting of C changes and GHG emissions for sustainable land management (SLM) practices such as afforestation is required for a variety of reasons, such as devising land management options and making policy. The Carbon Benefit Project (CBP) Simple Assessment Tool was employed to estimate changes in soil organic carbon (SOC) stocks and GHG emissions for wolfberry (Lycium barbarum L.) planting on secondary salinized land over a 10 year period (2004–2014) in the Jingtai oasis in Gansu with salinized barren land as baseline scenario. Results show that wolfberry plantation, an intensively managed ecosystem, served as a carbon sink with a large potential for climate change mitigation, a restorative practice for saline land and income stream generator for farmers in soil salinized regions in Gansu province. However, an increase in wolfberry production, driven by economic demands, would bring environmental pressures associated with the use of N fertilizer and irrigation. With an understanding of all of the components of an ecosystem and their interconnections using the Drivers-Pressures-State-Impact-Response (DPSIR) framework there comes a need for strategies to respond to them such as capacity building, judicious irrigation and institutional strengthening. Cost benefit analysis (CBA) suggests that wolfberry cultivation was economically profitable and socially beneficial and thus well-accepted locally in the context of carbon sequestration. This study has important implications for Gansu as it helps to understand the role cash trees can play in carbon emission reductions. Such information is necessary in devising management options for sustainable land management (SLM)

The Economics of Fruit and Vegetable Production Irrigated with Reclaimed Water Incorporating the Hidden Costs of Life Cycle Environmental Impacts

The estimation and quantification of external environmental costs (hidden costs) are crucial to sustainability assessments of treated wastewater reuse projects. These costs, however, are rarely considered in economic analysis studies. In this work, monetized life cycle assessment (LCA) and life cycle costing (LCC) were combined into a hybrid model to calculate cradle-to-farm gate external environmental costs (EEC) and internal costs (IC) of producing 1 t of plant-based product irrigated with reclaimed water in a Mediterranean context. The total cost was calculated by combining monetized LCA and LCC results. The results for the crops under consideration were 119.4 €/t for tomatoes, 344.4 €/t for table grapes, and 557 €/t for artichokes. Our findings show that there are significant hidden costs at the farm level, with EEC accounting for 57%, 23%, and 38% of the total cost of tomatoes, table grapes, and artichokes, respectively. Electricity use for water treatment and fertilization generated most of the EEC driven by the global warming, particulate matter, acidification, and fossil resource scarcity impact categories. When compared to groundwater, the higher internal costs of reclaimed water were offset by lower external costs, particularly when supported by low-energy wastewater treatment. This demonstrates that incorporating EEC into economic analyses might generate a better understanding of the profitability of treated wastewater reuse in crop production. In Italy and the Mediterranean region, research on the sustainability of water reuse in irrigation through life cycle thinking is still limited. Using a multi-metric approach, our analysis brought new insights into both economic and environmental performance – and their tradeoff relationships in wastewater reuse for irrigation of agricultural crops. In future research, it would be of interest to use different monetization methods as well as to investigate social externalities to explore their size and role in the total external costs

Is Dairy Effluent an Alternative for Maize Crop Fertigation in Semiarid Regions? An Approach to Agronomic and Environmental Effects

The reuse of effluents from intensive dairy farms combined with localized irrigation techniques (fertigation) has become a promising alternative to increase crop productivity while reducing the environmental impact of waste accumulation and industrial fertilizers production. Currently, the reuse of dairy effluents through fertigation by subsurface drip irrigation (SDI) systems is of vital importance for arid regions but it has been poorly studied. The present study aimed to assess the greenhouse gas (GHG) emissions, soil properties, and crop yield of a maize crop fertigated with either treated dairy effluent or dissolved granulated urea applied through an SDI system at a normalized N application rate of 200 kg N ha−1. Fertilizer application was divided into six fertigation events. GHG fluxes were measured during fertigation (62-day) using static chambers. Soil properties were measured previous to fertilizer applications and at the harvest coinciding with crop yield estimation. A slight increase in soil organic matter was observed in both treatments for the 20–60 cm soil depth. Both treatments also showed similar maize yields, but the dairy effluent increased net GHG emissions more than urea during the fertigation period. Nevertheless, the net GHG emissions from the dairy effluent were lower than the theoretical CO2eq emission that would have been emitted during urea manufacturing or the longer storage of the effluent if it had not been used, showing the need for life-cycle assessments. Local-specific emission factors for N2O were determined (0.07%), which were substantially lower than the default value (0.5%) of IPCC 2019. Thus, the subsurface drip irrigation systems can lead to low GHG emissions, although further studies are needed.EEA Hilario AscasubiFil: Lombardi, Banira. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina.Fil: Lombardi, Banira. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina.Fil: Orden, Luciano. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Hilario Ascasubi; ArgentinaFil: Orden, Luciano. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Varela, Patricio. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Hilario Ascasubi; Argentina.Fil: Garay, Maximiliano. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Iocoli, Gastón Alejandro. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Montenegro, Agustín Rodrigo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Hilario Ascasubi; ArgentinaFil: Sáez-Tovar, José. Universidad Miguel Hernández. Centro de Investigación e Innovación Agroalimentaria y Agroambiental; EspañaFil: Bustamante, María Ángeles. Universidad Miguel Hernández. Centro de Investigación e Innovación Agroalimentaria y Agroambiental; EspañaFil: Juliarena, María Paula. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas; Argentina.Fil: Juliarena, María Paula. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina.Fil: Juliarena, María Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina.Fil: Moral, Raúl. Universidad Miguel Hernández. Centro de Investigación e Innovación Agroalimentaria y Agroambiental; Españ

Evaluating soil productivity and climate change benefits of woody biochar soil amendments for the US Interior West

2018 Summer.Includes bibliographical references.Managing our lands to provide for today and the future requires sustainable land management practices that enhance productivity while reducing climate impacts. Proponents claim biochar soil amendments offer a comprehensive solution to enhance soil capacity to deliver water and nutrients to plants while decreasing climate impacts through reduced nitrous oxide (N2O) emissions from fertilizer use and carbon (C) sequestration. This dissertation evaluates such claims for woody biochar applications within the US Interior West; to enhance crop production and reduce N2O emissions in deficit irrigation agricultural systems, and to support forest road restoration efforts. It also employs laboratory incubations and soil biogeochemical modeling to predict and to better understand the controls on biochar's greenhouse gas mitigation potential. The field studies demonstrate that this woody biochar improved soil moisture content but its enhanced capacity to retain water did not alleviate plant water stress when water inputs were low. Similarly, in forest soils, this woody biochar amendment improved plant available N but at levels that did not impact productivity. In lab incubations this woody biochar reduced N2O emissions. While this reduction could not be explained by bulk soil mineral N transformations, the soil moisture regime did affect biochar's ability to reduce N2O emissions. Despite the observed biochar N2O emission reductions in incubated soils, under field conditions biochar effects on N2O emissions were inconclusive. When evaluating biochar's C sequestration potential, soil biogeochemical modeling revealed that 59 percent of the biochar C applied will be sequestered in soils after 100 years. Losses from biochar fragmentation and leaching may constitute a considerable proportion of the C losses. Of the applications considered, C sequestration remains the most promising use for biochar soil amendments within the US Interior West