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Securing land and water for food production through sustainable land reform: a nexus planning perspective 全文
2022
Nhamo, L. | Mpandeli, S. | Liphadzi, S. | Mabhaudhi, Tafadzwanashe
Land and water are vital resources for sustaining rural livelihoods and are critical for rural development as they form the basis of agriculture, the main economic activity for rural communities. Nevertheless, in most developing countries, land and water resources are unevenly distributed due to historical and socio-economic imbalances, hence the need for land reform policies to address these disparities. However, redistributing land without considering the interconnectedness of land and socio-ecological systems can compound existing food and water insecurity challenges. This study used a mixed research method, integrating both quantitative and qualitative data, to develop a framework to guide policy and decision-makers to formulate coherent strategies towards sustainable land redistribution programmes and achieve the desired outcomes. The approach was vital for integrating the broad and intricate interlinkages between water, land, and environmental resources. Therefore, the framework is based on transformative and circular models for informing strategic policy decisions towards sustainable land redistribution. The focus was on South Africa’s land redistribution plans and the implications on water and food security and rural development. The developed framework is designed to ensure the sustainability of agrarian reform and rural economic development. It is framed to address land and water accessibility inequalities, promote water and food security, and enhance rural development. A sustainable land redistribution increases the adaptive capacity of rural communities to climate change, enhances their resilience, and provides pathways towards Sustainable Development Goals (SDGs).
显示更多 [+] 显示较少 [-]Improving urban sustainability and resilience with the optimal arrangement of water-energy-food related practices 全文
2022
Liu, Shang-Keng | Lin, Zih-Ee | Chiueh, Pei-Te
Water-, energy-, and food (WEF) related practices, such as low impact development (LID), residential solar panels, and rooftop urban agriculture, have been applied to improve urban sustainability and resilience under climate change and urbanization. However, most practices require space. This requirement may result in competition for land. In addition, not all newly built practices benefit the environment from the life cycle perspective. Therefore, this study aims to develop a systematic WEF-related practice planning method to improve urban sustainability and resilience in a limited space. The core method is a multi-objective optimization model that considers the performance and environmental impacts of the selected practices. The assessment was conducted in a densely populated area in Taipei, the capital city of Taiwan, to describe the planning processes and demonstrate the feasibility of the methods. In the Taipei case, five goals were defined: the supply of WEF, the sponge city development target, and the greenhouse gas reduction target. The optimal results of the multi-objective optimization model indicated the closeness of the optimal implementation of WEF-related practices to achieving the goals. The results showed that the optimal arrangement of WEF-related practices could provide water supply benefits and was favorable for developing a sponge city. According to the sensitivities, to achieve urban sustainability and resilience, the priorities in order of importance are as follows: establish a rainwater harvesting system for buildings, encourage the implementation of rooftop photovoltaic systems, and improve the materials and processes used solar panel and bioretention cell production. The systematic planning method provides a quantitative assessment and delivers practical cross-sectoral integrated strategies for decision-making.
显示更多 [+] 显示较少 [-]Impact of urbanization on the food–water–land–ecosystem nexus: A study of Shenzhen, China 全文
2022
Shi, Xiangyun | Matsui, Takanori | Machimura, Takashi | Haga, Chihiro | Hu, Ang | Gan, Xiaoyu
The food–water–land–ecosystem (FWLE) nexus is fundamental for achieving sustainable development. This study examines the influence of urbanization on the FWLE nexus. Toward this end, land was deemed as an entry point. Therefore, the impact of urbanization on the nexus was explored based on changes in land use. We selected Shenzhen, a city in China, as the study area. First, a land change modeler was employed to analyze historical land-use changes from 2000 to 2010, to build transition potential submodels, and to project future land-use patterns for 2030 under a business-as-usual scenario. Second, based on land-use maps, we assessed habitat quality, water yield, and water supply from 2000 to 2030 using Integrated Valuation of Ecosystem Services and Tradeoffs. Moreover, crop production was estimated according to statistical materials. Finally, the study presents the analyses and discussion of the impacts of urbanization on ecosystem services related to the FWLE nexus. The results of land-use changes indicated that a significant expansion of artificial surfaces occurred in Shenzhen with varying degrees of decrease in cultivated land, forest, and grassland. Furthermore, habitat quality, water supply, and crop production decreased evidently due to rapid urbanization. In contrast, the total water yield indicated an upward trend owing to the increased water yield from increasing artificial surfaces, whereas water yield from other land-use areas declined, such as the forest and grassland. The results demonstrated a significant positive correlation between artificial surfaces and total water yield. However, negative correlations were observed in the interaction among habitat quality, water supply, and crop production. The study presented temporal and spatial assessments to provide an effective and convenient means of exploring the interactions and tradeoffs within the FWLE nexus, which, thus, contributed to the sustainable transformation of urbanization.
显示更多 [+] 显示较少 [-]Optimization of biochar systems in the water-food-energy-carbon nexus for sustainable circular agriculture 全文
2022
Li, Haiyan | Li, Mo | Fu, Qiang | Cao, Kaihua | Liu, Dong | Li, Tianxiao
The increasing pressures of global warming, population growth and epidemic occurrence are causing challenges in meeting the growing requirements for water, energy and food. In particular, the contradiction between the supply and demand for water, food, and energy is exacerbated by inefficient resource utilization and carbon emission increase. Incorporation of the interlinked aspects of water, energy, food and carbon emissions from agricultural systems into one water-food-energy-carbon nexus facilitates integrated resource management. Biochar application to farmland is a potential strategy for carbon management and agricultural productivity improvement. The integration of biochar systems and the water-food-energy-carbon nexus is an efficient and coordinated alternative method for sustainable agricultural management and a crucial strategy for addressing water, energy and food security issues. Accordingly, this paper proposes an approach for the synergistic regulation of water, land, energy, and carbon emissions in a circular agricultural system by balancing water supply and demand, land allocation, electricity consumption, and economic upgrading principles. A two-stage circular agriculture framework is constructed, with biochar and electricity generated from agricultural residues at the first stage and employed at the second stage. Economic-environmental-energy harmonization is considered in the methodology, and the agrotechnical potential of biochar is quantified via crop yield increase and greenhouse gas emission reduction functions. This approach can assist decision makers in providing the best policy options given certain agricultural resources to achieve the maximum economic performance of the system while minimizing environmental side effects. In this paper, the model framework is applied to the Sanjiang Plain in northeastern China to verify the feasibility of the approach. The results indicate that the external electricity demand is reduced by 87.8% due to the generation of biofuels. Cropland greenhouse gas emissions are reduced by 34.09%–67.06% via the application of biochar. This study proposes an optimization method with important implications for the improvement of regional cropland management techniques and development of sustainable circular agriculture. This methodology can be extended to other agriculture-centered regions with limited resources and environmental problems.
显示更多 [+] 显示较少 [-]Desalted duck egg white nanogels as Pickering stabilizers for food-grade oil-in-water emulsion 全文
2022
Jingyun Zhao | Xiaohan Guo | Ze Chen | Yalei Dai | Hongshan Liang | Qianchun Deng | Shugang Li | Bin Zhou
Achieving the reuse of traditional egg by-products, salted duck egg whites (SEW), is an urgent problem to be solved. In this current work, we constructed a heat-induced gel-assisted desalination method for SEW. Subsequently, a top-down way was utilized to prepare desalted duck egg protein nanogels (DEPN) with uniformly distributed diameters and their application in the oil/water (O/W) interface system was explored. The results revealed that the increase of DEPN concentration could lower the droplet size, however, the size was negatively correlated with the oil phase fraction. Moreover, the effect of pH, ionic strength, and temperature on the emulsion stability demonstrated that the DEPN-stabilized emulsion displayed superior physical stability under different conditions. The addition of NaCl resulted in the significant decrease in droplet size of the emulsion, while further increasing the NaCl concentration, the droplet size did not decrease accordingly. Besides, heat-treatment and cold-treatment had little negative effect on the stability of the emulsion. Even if the droplet size of the emulsion increased at 80 °C for 3 h, the morphology of the emulsion remained unchanged. Our study demonstrated DEPN had great potential as a stabilizer for food-grade Pickering emulsions.
显示更多 [+] 显示较少 [-]Multilayers of Renewable Nanostructured Materials with High Oxygen and Water Vapor Barriers for Food Packaging 全文
2022
Pasquier, Eva | Mattos, Bruno D. | Koivula, Hanna | Khakalo, Alexey | Belgacem, Mohamed Naceur | Rojas, Orlando J. | Bras, Julien
Natural biopolymers have become key players in the preparation of biodegradable food packaging. However, biopolymers are typically highly hydrophilic, which imposes limitations in terms of barrier properties that are associated with water interactions. Here, we enhance the barrier properties of biobased packaging using multilayer designs, in which each layer displays a complementary barrier function. Oxygen, water vapor, and UV barriers were achieved using a stepwise assembly of cellulose nanofibers, biobased wax, and lignin particles supported by chitin nanofibers. We first engineered several designs containing CNFs and carnauba wax. Among them, we obtained low water vapor permeabilities in an assembly containing three layers, i.e., CNF/wax/CNF, in which wax was present as a continuous layer. We then incorporated a layer of lignin nanoparticles nucleated on chitin nanofibrils (LPChNF) to introduce a complete barrier against UV light, while maintaining film translucency. Our multilayer design which comprised CNF/wax/LPChNF enabled high oxygen (OTR of 3 ± 1 cm³/m²·day) and water vapor (WVTR of 6 ± 1 g/m²·day) barriers at 50% relative humidity. It was also effective against oil penetration. Oxygen permeability was controlled by the presence of tight networks of cellulose and chitin nanofibers, while water vapor diffusion through the assembly was regulated by the continuous wax layer. Lastly, we showcased our fully renewable packaging material for preservation of the texture of a commercial cracker (dry food). Our material showed functionality similar to that of the original packaging, which was composed of synthetic polymers.
显示更多 [+] 显示较少 [-]Research on the competitive and synergistic evolution of the water-energy-food system in China 全文
2022
Sun, Caizhi | Hao, Shuai
Water, energy, and food are essential and strategic resources for human well-being and socio-economic development and form the water-energy-food (WEF) system with competition and synergy. The competitive and synergistic evolution model was developed to remedy the limitations in quantitatively analyzing the tradeoffs and synergies of the WEF system. Firstly, an assessment model was developed for measuring the synergy and competition of the WEF system based on the order degree of each subsystem (That is, the development degree of each subsystem) and synergy theory. Then the synergy evolution model (SEM), with the help of a logistic model and accelerated genetic algorithm (AGA) model, was developed to measure and identify the steady-state. Furthermore, an empirical study was conducted with 30 provinces in China as examples. The results indicated that the food subsystem had the highest average order degree (0.347), followed by the energy subsystem (0.305), and the water subsystem had the lowest (0.281). The degree of order of the three subsystems exhibited an upward trend in time and has differences in the spatial distribution. Also, the results showed that synergistic, restrictive, and competitive relationships exist within the WEF system. Areas with competitive and restrictive relationships are mainly located in South China and North China, respectively, within the relationship between the water and energy subsystems. The entire country showed a restrictive relationship between the water and food subsystems. The energy and food subsystems showed that the eastern regions with relationship, while the western regions with competitive and restrictive relationship. Finally, effective measures (e.g., optimize the industrial structure, continuing to implement the strategy of “storing grain in the land and technology”, and to hold the arable land minimum) are suggested to achieve the WEF system coordinated and sustainable development. We believe that the assessment model is also applicable to assess the other complex and dynamic system worldwide that involve multiple factors.
显示更多 [+] 显示较少 [-]Caja de herramientas para el análisis del Nexo entre agua, energía y alimentos 全文
2022
CDKN Team
Biodisponibilidad de amoxicilina oral administrada en agua y alimento a lechones de recría 全文
2022
Decundo, Julieta María | Dieguez, Susana Nelly | Martínez, Guadalupe | Pérez, Denisa Soledad | Amanto, Andres Fabian | Soraci, Alejandro Luis
INTRODUCCIÓN La amoxicilina se encuentra entre los antibióticos más utilizados en producción porcina. La forma de administración de elección es la vía oral, donde el antibiótico se vehiculiza a través del agua de bebida o del alimento (1). Estas matrices pueden alterar los procesos farmacocinéticos de la AMX y su disposición sistémica. El ayuno también puede modificar los parámetros farmacocinéticos de los antibióticos Los estudios farmacocinéticos/farmacodinámicos en los cuales se establecen los planes posológicos de las formulaciones antibióticas comerciales se realizan en animales que son ayunados antes de la administración del antibiótico. En las producciones intensivas, los cerdos nunca son ayunados al momento de recibir un tratamiento antimicrobiano. Dicha situación es causal de discordancia entre los resultados obtenidos experimentalmente y los resultados terapéuticos encontrados en las granjas porcinas (2). El objetivo del presente trabajo fue evaluar el impacto del vehículo de administración (agua o alimento) y el efecto del ayuno sobre la biodisponibilidad de amoxicilina oral administrada a lechones de destete. MATERIAL Y MÉTODOS El estudio se realizó siguiendo un diseño experimental completamente aleatorizado. Se utilizaron 12 cerdos clínicamente sanos, de un peso de 14 ± 2 kg, divididos al azar en 3 grupos, los cuales recibieron una dosis oral de amoxicilina trihidrato 50% (AMX) de 20 mg/kg disuelta en agua (40 mgCaCO3/L pH 7,3) o incorporada en el alimento, según corresponda. Dos grupos recibieron el antibiótico disuelto en agua: con un periodo de ayuno de 12 horas (grupo A) o sin previo ayuno (grupo B). Al grupo C se le administró la dosis de AMX mezclada en una alícuota de alimento. Además del tratamiento oral, cada animal recibió una dosis intravenosa de 15 mg/kg de AMX para el cálculo de biodisponibilidad absoluta (BA). Se recolectaron muestras de sangre a tiempos estandarizados mediante la técnica de cateterismo yugular y se analizaron por HPLC-UV. El software PKSolution® fue utilizado para obtener las áreas bajo la curva (AUC0-24) concentración/tiempo. La BA fue calculada según la ecuación: BA= (AUCoral * DosisIV)/ (AUCIV * Dosisoral)*100 Se realizó un ANOVA para determinar el efecto de los tratamientos (grupos) y test de Tukey para detectar diferencias entre ellos (p<0,05). RESULTADOS La mayor BA se obtuvo para el grupo A con un valor promedio de 37,25 ± 8,25. El grupo B alcanzó una BA promedio de 23,18 ± 5,30, mientras que el grupo C reportó el valor promedio más bajo de BA (9,69 ± 0,64). El ANOVA arrojó efecto de los tratamientos (p<0,001) con diferencias estadísticamente significativas entre los 3 grupos. La figura 1 muestra las curvas de concentración plasmática en función del tiempo para los 3 grupos evaluados. 050010001500 0 1 2 3 4A B C Tiempo (minutos) Concentración plasmática (ppm) Figura 1: perfiles plasmáticos de AMX para los grupos A (agua, animales ayunados), B (agua, animales sin ayuno) y C (alimento). DISCUSIÓN La presencia del alimento en el tracto gastrointestinal mostró un efecto negativo sobre la BA cuando la AMX se administró disuelta en agua. Potenciales interacciones entre AMX y componentes del alimento podrían limitar su absorción y consecuentemente su BA. Adicionalmente, el antibiótico compite con proteínas presentes en el alimento por el mecanismo de absorción, ya que ambas sustancias se absorben mediante transportadores de tripéptido, dipétidos y aminoácidos (3). Por otra parte, la administración de AMX mezclada con el alimento arrojó los valores más bajos de BA mostrando diferencias con la administración del antibiótico disuelto en agua. Cuando el antibiótico se vehiculiza en el alimento, tiene que disolverse en los fluidos biológicos para ser absorbido, proceso que demanda tiempo y que está condicionado por la difusión del antimicrobiano desde la matriz que lo rodea. A su vez, el pasaje a través del estómago de la AMX disuelta en agua es más rápido lo que resulta en un menor tiempo de contacto entre el antibiótico y los componentes del alimento presentes en el tracto gastrointestinal (2). La baja BA obtenida al administrar AMX mezclada con el alimento o vehiculizada en agua a animales sin ayuno previo, podría conducir a dosificación errática, fracaso terapéutico, acumulación de antibiótico en el ambiente y aumento del riesgo de resistencia bacteriana. | Fil: Decundo, Julieta María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; Argentina | Fil: Dieguez, Susana Nelly. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; Argentina | Fil: Martínez, Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; Argentina | Fil: Pérez, Denisa Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; Argentina | Fil: Amanto, Andres Fabian. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias; Argentina | Fil: Soraci, Alejandro Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; Argentina | XXI Jornadas de Actualización Porcina | Rio Cuarto | Argentina | Universidad Nacional de Río Cuarto
显示更多 [+] 显示较少 [-]Estimating the Water and Carbon Footprints of Growing Avocados in the Munich Metropolitan Region Using Waste Heat as a Water-Energy-Food Nexus Potential 全文
2022
Lukas Becker | Daphne Gondhalekar
Avocados, which have been labeled a superfood and are very popular around the world, are often grown in areas with water scarcity and have long-distance transports to their end consumer. Water and carbon footprints could be reduced by using greenhouse farming, waste heat and rainwater. This study aims to determine whether avocados and other exotic fruits could be locally or regionally grown in greenhouse systems in Bavaria heated using waste heat and examines whether this approach decreases the resulting water and carbon footprints. To test these hypotheses, the waste heat potential is estimated by analyzing a database provided by the Bavarian Environment Agency. Data on water and carbon footprints are extracted from databases by The Water Footprint Network and FAOSTAT. As a local case study, a greenhouse system using waste heat of a nearby glass factory in Upper Franconia is considered. The results show a tremendous waste heat potential for Bavaria and Munich with reduced carbon, but similar water footprints compared to international avocado production. The required area for these avocado farms would only amount to 0.016% of Bavaria's or 0.02% of Munich's total area. With more uncomplicated handling and earlier fruit bearing, fruits like papaya, guava, or carambola seem to be better suited for greenhouse farming than avocados. Waste heat supported farming in controlled environments can require significantly less water through modern irrigation techniques and should be considered when designing new food security concepts for urban or rural areas.
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