Letteratura scientifica selezionata sul tema "Savings of fresh water and arable land"

Demand for food and water are increasing while the extent of arable land and accessible fresh water are decreasing. This poses global challenges as economies continue to develop and the population grows. With agriculture as the leading consumer of water, better understanding how water is used to produce food may help support the increase of Crop Water Productivity (CWP; kg/m3), the ratio of crop output per unit of water input (or crop per drop). Previous large-scale CWP studies have been useful for broad water use modeling at coarser resolutions. However, obtaining more precise CWP, especially for specific crop types in a particular area and growing season as outlined here are important for informing farm-scale water management decision making. Therefore, this study focused on California’s Central Valley utilizing high-spatial resolution satellite imagery of 30 m (0.09 hectares per pixel) to generate more precise CWP for commonly grown and water-intensive irrigated crops. First, two products were modeled and mapped. 1. Landsat based Actual Evapotranspiration (ETa; mm/d) to determine Crop Water Use (CWU; m3/m2), and 2. Crop Productivity (CP; kg/m2) to estimate crop yield per growing season. Then, CWP was calculated by dividing CP by CWU and mapped. The amount of water that can be saved by increasing CWP of each crop was further calculated. For example, in the 434 million m2 study area, a 10% increase in CWP across the 9 crops analyzed had a potential water savings of 31.5 million m3 of water. An increase in CWP is widely considered the best approach for saving maximum quantities of water. This paper proposed, developed, and implemented a workflow of combined methods utilizing cloud computing based remote sensing data. The environmental implications of this work in assessing water savings for food and water security in the 21st century are expected to be significant.

Resource use and environmental impacts are important factors relating to the sustainability of beef production in Australia. This study used life cycle assessment to investigate impacts from grass-finished beef production in eastern Australia to the farm gate, reporting impacts per kilogram of liveweight (LW) produced. Mean fossil fuel energy demand was found to vary from 5.6 to 8.4 MJ/kg LW, mean estimated fresh water consumption from 117.9 to 332.4 L/kg LW and crop land occupation from 0.3 to 6.4 m2/kg LW. Mean greenhouse gas emissions ranged from 10.6 to 12.4 kg CO2-e/kg LW (excluding land use and direct land-use change emissions) and were not significantly different (P > 0.05) for export or domestic market classes. Enteric methane was the largest contributor to greenhouse gas emissions, and multiple linear regression analysis revealed that weaning rate and average daily gain explained 80% of the variability in supply chain greenhouse gas emissions. Fresh water consumption was found to vary significantly among individual farms depending on climate, farm water supply efficiency and the use of irrigation. The impact of water use was measured using the stress-weighted water use indicator, and ranged from 8.4 to 104.2 L H2O-e/kg LW. The stress-weighted water use was influenced more by regional water stress than the volume of fresh water consumption. Land occupation was assessed with disaggregation of crop land, arable pasture land and non-arable land, which revealed that the majority of beef production utilised non-arable land that is unsuitable for most alternative food production systems.

This study conducted a life cycle assessment (LCA) investigating energy, land occupation, greenhouse gas (GHG) emissions, fresh water consumption and stress-weighted water use from production of export lamb in the major production regions of New South Wales, Victoria and South Australia. The study used data from regional datasets and case study farms, and applied new methods for assessing water use using detailed farm water balances and water stress weighting. Land occupation was assessed with reference to the proportion of arable and non-arable land and allocation of liveweight (LW) and greasy wool was handled using a protein mass method. Fossil fuel energy demand ranged from 2.5 to 7.0 MJ/kg LW, fresh water consumption from 58.1 to 238.9 L/kg LW, stress-weighted water use from 2.9 to 137.8 L H2O-e/kg LW and crop land occupation from 0.2 to 2.0 m2/kg LW. Fossil fuel energy demand was dominated by on-farm energy demand, and differed between regions and datasets in response to production intensity and the use of purchased inputs such as fertiliser. Regional fresh water consumption was dominated by irrigation water use and losses from farm water supply, with smaller contributions from livestock drinking water. GHG emissions ranged from 6.1 to 7.3 kg CO2-e/kg LW and additional removals or emissions from land use (due to cultivation and fertilisation) and direct land-use change (due to deforestation over previous 20 years) were found to be modest, contributing between –1.6 and 0.3 kg CO2-e/kg LW for different scenarios assessing soil carbon flux. Excluding land use and direct land-use change, enteric CH4 contributed 83–89% of emissions, suggesting that emissions intensity can be reduced by focussing on flock production efficiency. Resource use and emissions were similar for export lamb production in the major production states of Australia, and GHG emissions were similar to other major global lamb producers. The results show impacts from lamb production on competitive resources to be low, as lamb production systems predominantly utilised non-arable land unsuited to alternative food production systems that rely on crop production, and water from regions with low water stress.

Land consolidation is an effective means of promoting the regularization of fragmented arable land, optimizing the allocation of land resources and improving the environment in farming areas, as well as an important means of increasing the economic returns of farming households, and it is important to scientifically assess the ecological and economic benefits of agricultural land consolidation. In this study, participatory rural assessment (PRA) was used to investigate, in detail, the meaning, satisfaction and changes in farmland rehabilitation before and after implementation. The accuracy of the remote sensing data was verified through an experiment on the net cultivation coefficient. We used a sample of 447 farmers from nine villages in Manas County to study the differences in plot area, crop unit value, income and irrigation before and after the farmers’ integration. We found that, after the integration of farmland, the cultivated area increased significantly, the crop unit yield increased by at least 42.66%, the average income of farmers increased by a value of RMB 4324/ha and the water savings were all higher than 7.18 m3/ha. At the same time, after the integration of farmland, the number of plots was significantly reduced, the arable land became more regular and the microclimate of the farmland improved significantly. The government and individuals should follow the concept and construction requirements of the “community of life in mountain, water, forest, lake, grass and sand”, consider the economic and ecological benefits of land consolidation, ensure the quality of farmland ecosystems, actively explore new models of land consolidation and stimulate the economic vitality of rural areas.

Food resources are limited in arid countries such as the United Arab Emirates (UAE); the salinity of the groundwater, together with a lack of natural fresh water sources and arable land, force the country to import most of its food. However, seaweed could play an important role in providing a locally available food resource, as it does not require fresh water and arable land to grow. The traditional use of several seaweed species as food sources has been documented in Asia and the Americas, where their nutritional composition has been well reported. Although the UAE’s aquatic environment is quite harsh due to high water salinity (over 40 g/L) and high surface water temperatures (over 35 °C), its native seaweed species could play a role as a food source in this arid region, thereby bolstering the country’s level of food security. To evaluate its potential in this context, fresh samples of the native Ulva intestinalis seaweed were collected in the shallow waters of Abu Dhabi Emirate, UAE. These samples were calculated to contain 34.38 ± 0.24 kcal, with a biomass composition of 5.185 ± 0.04% carbohydrate, 3.32 ± 0.14% protein, and 0.04 ± 0.01% fat (by dry matter). Of all the minerals present in the biomass, potassium had the highest concentration (7947 ± 319.5 ppm), followed by magnesium (3075.9 ± 1357 ppm) and sodium (756.3 ± 478 ppm). The water-soluble vitamins B1, B2, B3, B6, and C were below the detection limit in the samples. The rich concentration of essential minerals such as potassium, magnesium, iron and zinc in Ulva intestinalis makes it a promising novel food source. To the best of our knowledge, this is the first experimental study to examine the feasibility of using seaweed that is native to the UAE as a nutritional and sustainable food source in order to address the challenge of food security currently being faced by the country.

This study compared the hydroponic and soil cultivation systems for lettuce and spinach production in India’s cold desert, high-altitude Trans-Himalayan region. Hydroponic cultivation is a soilless technique that provides fresh vegetables in regions with environmental stress and limited arable land. The experiment was conducted in hydroponic structures designed for leafy vegetable cultivation, including vertical and horizontal circulated nutrient film technique (NFT), non-circulated systems, and soil cultivation in an open, naturally ventilated double-layer polycarbonate greenhouse in Ladakh, India. Results showed that lettuce and spinach grown in the vertical circulated NFT system had significantly better plant growth characteristics such as plant height, number of leaves, leaf area, fresh weight, and yield than horizontal NFT, non-circulated, and soil systems. Moreover, fresh produce from vertical and horizontal NFT systems had higher nitrate content, soluble sugar content, and total sweetness index, indicating better crispiness of the produce. Mineral nutrient contents (Ca, Mg, B, Cu, Mn, Zn, Fe, and Ni) were also higher in the circulated NFT system compared to other systems studied. Thus, this study demonstrated that lettuce and spinach grown in NFT systems produced significantly higher yields with better nutritional quality than soil-grown systems in the Trans-Himalayan region. Hydroponic systems are recommended for successfully producing nutrient-rich vegetables in areas with limited water and arable land. This is the first demonstration of hydroponic systems in high-altitude cold desert conditions for growing leafy greens, and it has promising implications for sustainable agriculture.

Utilisation of water, energy and land resources is under pressure globally because of increased demand for food, fibre and fuel production. Australian pork production utilises these resources both directly to grow and process pigs, and indirectly via the consumption of feed and other inputs. With increasing demand and higher costs associated with these resources, supply chain efficiency is a growing priority for the industry. This study aimed to quantify fresh water consumption, stress-weighted water use, fossil fuel energy use and land occupation from six case study supply chains and the national herd using a life cycle assessment approach. Two functional units were used: 1 kg of pork liveweight (LW) at the farm-gate, and 1 kg of wholesale pork (chilled, bone-in). At the farm-gate, fresh water consumption from the case study supply chains ranged from 22.2 to 156.7 L/kg LW, with a national average value of 107.5 L/kg LW. Stress-weighted water use ranged from 6.6 to 167.5 L H2O-e /kg LW, with a national average value of 103.2 L H2O-e /kg LW. Fossil fuel energy demand ranged from 12.9 to 17.4 MJ/kg LW, with a national average value of 14.5 MJ/kg LW, and land occupation ranged from 10.9 to 16.1 m2/kg LW, with a national average value of 16.1 m2/kg LW and with arable land representing 97% to 99% of total land occupation. National average impacts associated with production of wholesale pork, including impacts from meat processing, were 184 ± 43 L fresh water consumption, 172 ± 53 L H2O-e stress-weighted water, 27 ± 2.6 MJ fossil fuel energy demand and 25.9 ± 5.5 m2 land/kg wholesale pork. Across all categories through to the wholesale product, resource use was highest from the production of feed inputs, indicating that improving feed conversion ratio is the most important production metric for reducing the resource use. Housing type and energy generation from manure management also influence resource use requirements and may offer improvement opportunities.

Soil pH is one of the most important limiting factors for crop cultivation, including maize. About 30-40% of the world's arable land is acidic, and over a billion ha is alkaline. Today, there are 205 million ha of arable land under maize in the world, so it ranks third in area after rice and wheat. Maize hybrids have wide genetic variability and high pH tolerance. We tested the tolerance of maize hybrids seedlings of ZP 4708 and ZP 5797 to pH 5, 6, 7, and 8. Results showed that hybrid ZP 4708 has a higher adaptability to low and high pH, due to the higher value of germination energy (GE), shoot length (ShL), shoot fresh weight (ShFW), shoot dry weight (ShDW), germination rate index (GRI), and seedling vigor index (SVI) than hybrid ZP 5797. Results further showed, on average for hybrids, that pH 5 and pH 8 significantly decreased the GE, root length (RL), ShL, root fresh weight (RFW), ShFW, root dry weight (RDW), shoot fresh weight (ShDW), and SVI. These parameters did not differ significantly between pH 6 and pH 7. Seed germination was not affected by the pH, indicating that the seed vigor of both hybrids supports full germination potential. However, it could be expected that exposure to the lowest and highest pH values of the medium could affect seedlings growth in the field conditions, even though germination is high. SVI showed a positive and significant correlation with all investigated parameters, except germination (G) and relative seedling water content (RSWC).

Human gut microbiota plays an important role in several metabolic processes and human diseases. Various dietary factors, including complex carbohydrates, such as polysaccharides, provide abundant nutrients and substrates for microbial metabolism in the gut, affecting the members and their functionality. Nowadays, the main sources of complex carbohydrates destined for human consumption are terrestrial plants. However, fresh water is an increasingly scarce commodity and world agricultural productivity is in a persistent decline, thus demanding the exploration of other sources of complex carbohydrates. As an interesting option, marine seaweeds show rapid growth and do not require arable land, fresh water or fertilizers. The present review offers an objective perspective of the current knowledge surrounding the impacts of seaweeds and their derived polysaccharides on the human microbiome and the profound need for more in-depth investigations into this topic. Animal experiments and in vitro colonic-simulating trials investigating the effects of seaweed ingestion on human gut microbiota are discussed.

Fluvial environments have always played a crucial role in human history. The necessity of fertile land and fresh water for agriculture has led populations to settle in floodplains more frequently than in other environments. Floodplains are complex human–water systems in which the mutual interaction between anthropogenic activities and environment affected the landscape development. In this paper, we analyzed the evolution of the Central Po Plain (Italy) during the Medieval period through a multi-proxy record of geomorphological, archaeological and historical data. The collapse of the Western Roman Empire (5th century AD) coincided with a progressive waterlogging of large floodplain areas. The results obtained by this research shed new light on the consequences that Post-Roman land and water management activities had on landscape evolution. In particular, the exploitation of fluvial sediments through flood management practices had the effect of reclaiming the swamps, but also altered the natural geomorphological development of the area. Even so, the Medieval human activities were more in equilibrium with the natural system than with the later Renaissance large-scale land reclamation works that profoundly modified the landscape turning the wetland environment into the arable land visible today. The analysis of fluvial palaeoenvironments and their relation with past human activities can provide valuable indications for planning more sustainable urbanized alluvial landscapes in future.

La diminution globale des ressources en eau douce et en terres arables non salinisées à travers le monde a conduit à l’essor mondial de cultures biosalines, à partir de plantes « halophytes » capables de croître et de se multiplier sous de fortes concentrations en sel. Parmi les espèces halophytes candidates à ce type de productions biosalines en Nouvelle-Calédonie, cinq espèces ont été sélectionnées sur la base du potentiel retrouvé au sein de leurs genres : Suaeda maritima, Sarcocornia quinqueflora, Enchylaena tomentosa, Atriplex jubata et Salsola australis. La culture de ces plantes pourrait englober plusieurs applications biotechnologiques, touchant les secteurs de l’agro-alimentaire, de la cosmétique, des bioénergies ou encore de la restauration écologique. Parmi ces applications, la production de légumes biosalins fonctionnels (riches en métabolites fonctionnels d’intérêt) est en recrudescence au niveau mondial. Le monde scientifique a en effet clairement établi un lien entre la tolérance au sel et la richesse des plantes halophytes en plusieurs métabolites fonctionnels d’intérêt (tels que les acides gras polyinsaturés ou les antioxydants).Néanmoins, les valeurs fonctionnelles des plantes halophytes sont supposées variables et dictées par leurs réponses aux variabilités de l’environnement (tolérance au sel, nutrition, etc.). L’étude de telles relations est indispensable à l’établissement du potentiel agronomique local d’espèces d’intérêt telles que celles sélectionnées.Ceci a été l’objet du présent travail de thèse. Il a eu pour but d’évaluer le potentiel de chacune des espèces en tant que source de composés fonctionnels mais aussi d’évaluer leurs variabilités selon les modifications, naturelles ou contrôlées de l’environnement. A ce titre, il montre que les tissus comestibles de ces cinq espèces ont des valeurs fonctionnelles élevées en minéraux essentiels, acides gras polyinsaturés et/ou antioxydants en comparaison avec plusieurs normes diététiques et légumes fonctionnels d’intérêt. Il montre également des relations entre les compositions en acides gras et en éléments essentiels des espèces et les caractéristiques spatio-temporelles de leur milieu naturel. Il montre enfin des relations entre la croissance et les compositions en acides gras et/ou en antioxydants des espèces et différents traitements expérimentaux appliqués en serre, combinant salinité et nutrition azotée sous différentes formes. A terme, ces différents résultats pourront contribuer à l’émergence de cultures biosalines expérimentales à plus large échelle en Nouvelle-Calédonie et à des préconisations de pratiques culturales optimales pour ces cultures. Ils soutiennent ainsi des objectifs centraux de la politique agricole du territoire comme le verdissement et la diversification de l’agriculture
The global decrease of freshwaters and non-salinized lands around the world led to the development of saline crops worldwide, from halophyte plants, capable of grow and multiply in high salty environments. Based on intra-genera potentials, five halophytes from Amaranthaceae family drew attention to test their saline crop potential in New Caledonia: Suaeda maritima, Sarcocornia quinqueflora, Enchylaena tomentosa, Atriplex jubata and Salsola australis. The cultivation of such plants could encompass several biotechnological applications, belonging to the sectors of agri-foods, cosmetics, bioenergy or ecological restoration. Among these applications, the production of functional vegetables (rich in functional metabolites) from halophyte species is increasing worldwide. The scientific world has clearly established a link between salt tolerance of halophytes and their richness in functional metabolites (such as polyunsaturated fatty acids or antioxidants). But, the functional values of halophytes are assumed to be variable and dictated by their responses to environment (salt tolerance, nutrition, etc.). So, the study of such relationships is essential to define the local agronomic potential of potential future crop species. The present thesis work aimed to assess the potential of each of the five selected species as source of functional metabolites, as well as their functional variabilities according to environmental changes, whether natural or controlled. As such, it shows that the edible tissues of the five species have high functional values for essential minerals, polyunsaturated fatty acids and antioxidants in comparison with dietary standards and with other functional vegetables. It also shows the relationships between the compositions for polyunsaturated fatty acid and essential elements in species and the spatio-temporal variations of their natural environment. Finally, it shows the relationships between the growth and the compositions for antioxidants and fatty acids in species and experimental treatments, combining different salinity and nitrogen forms.Ultimately, such results are intended to help the emergence of experimental saline crops at larger scale in New Caledonia, in particular trough recommendations of optimal cultivation practices. Thus, they support some objectives of agricultural local policy, such as the greening and the diversification of agriculture

The social entrepreneurs consider solving the social problem first rather than minting profits. As the world today is suffering from the problem of rising population, the food demands are destined to rise in the times to come. The shrinking arable land, less availability of fresh water, concentration of population in towns and cities, etc. are becoming a threat to the agriculture sector. Thus, the agriculture sector requires innovative practices that at times comes with cost. Entrepreneurship with an objective of minting profit might escalate the price of the agricultural produce, and being a primary sector, it might further lead to inflation in other sectors as well. To these issues, social entrepreneurship appears to be a potential solution that has been discussed considering literature and reports in this chapter.

It is estimated that the global population will reach approximately 10 billion people by 2050 and 66% of the world population will live in urban areas. This growth in cities creates demand for fresh products to maintain a healthy population, a product that often exposed to a long journey to reach the consumer, not only losing quality and nutritive value in the process, but also requiring a significant cost of fossil fuel for transportation and storage. However, the world’s agricultural land among being limited, is also facing major problems such as pollution, salinization and drought that do not favor crop production. The need for food security has paved the way for landless agriculture, becoming more popular in the urban area and becoming a part of urban farming. This article aims to examine hydroponic technologies to help expand the knowledge of their application in terms of science, origin, dynamics and farming systems. Among the benefits of soilless cultures; reservation of cultivated land for main crops; saving at least 90% of irrigation water; use of almost constant amount of recycled water; successfully growing almost every vegetable crops and having highest productivity compared to conventional agriculture. Therefore, it is an indispensable solution in areas where arable land is not available or in saline-prone areas, in short, wherever there is competition for land and water. The purpose of this study is an overview of soilless farming systems, explaining the most widely used hydroponic system, the importance of water quality, nutrient content, grown crops and ultimately cost benefit in terms of economics.

The U.S. Department of Defense (DoD) has recently shown an interest in incorporating resource efficiency into decision-making processes, including decisions that pertain to Forward Operating Military Base Camp (FOB) equipment. Often deployed in environments without access to grid utilities, FOBs require costly deliveries by land or air of resources such as fuel and fresh water. Resource-efficient FOB designs have the potential to reduce supply costs, but competing objectives and uncertain operational conditions complicate the design process. For example, integration of solar photovoltaic panels into existing designs has the potential to reduce the need to burn fuel in generators, however solar panels have up-front logistical and monetary costs that limit widespread use. There are also uncertainties associated with available solar energy and camp electrical loads. The research described here uses computer modeling and simulation of a real FOB subsystem under different operational scenarios to develop configurations of solar panels and batteries that, when integrated with an existing FOB design, maximize resource savings but minimize logistical and monetary costs, showing the benefit of a holistic design strategy that accounts for scenario variation. This research will also show that while different hardware configurations prove most efficient under different scenarios and objectives, certain hardware configurations provide good performance under all scenarios and objectives.

Over the last few decades, the organic agriculture sector has experienced sustained growth. Globally, as well as in the European Union and Portugal, organic production accounts for just under 10% of total Utilised Agricultural Area (UAA) (FiBL, 2019; Eurostat, 2019; DGADR, 2019; INE, 2019; GPP, 2019). This growth has been seen in terms of production, number of producers, amount of retail sales, imports and exports. This article attempts to build on the multi-level perspective (MLP) of the socio-technical (ST) transitions theory by employing a whole systems analysis (Geels, 2018) of organic agriculture in Portugal, which defends an integrated vision of the systems, where multiple interactions occur within and among the niche, the regime and the landscape levels. This approach has been employed in order to develop a critical analysis of the current state of the Portuguese organic agriculture sector, stressing the multiplicity of elements that are contributing to the agro-food system´s transformation into a more sustainable one. In fact, the agro-food system is related with climate change but also has connections with other domains such as public health, water management, land use and biodiversity. Therefore, it is affected by shifts in these areas. This analysis considers developments in increasing domestic organic production, number of producers, amount of retail sales, imports, exports, market innovations, and the sector´s reconfiguration. The organic sector´s increase has been attributed to European regulation, institutionalization, standardization, farmer certification, external (government) subsidy support programs, incremental market improvements (visibility and product access), the emergence of new retailers, the rise of supporting consumers and a shift away from conventional agriculture (Truninger, 2010; DGADR, 2019; Pe´er et al, 2019). However, together with positive incentives, this sector also faces numerous barriers that are hindering a faster transformation. Difficulties for the sector to date have included: product placement; a disconnect between production, distribution and marketing systems; high transport costs; competition from imports; European subsidies focused on extensive crops (pastures, olive groves, and arable crops), entailing a substantial growth in the area of pasture to the detriment of other crops; the fact that the products that are in demand (fresh vegetables and fruit) are being neglected by Portuguese producers; expensive certification procedures; lack of adequate support and market expertise for national producers; the hybrid configuration of the sector; and price. Organic agriculture as a niche-innovation is still not greatly contributing to overall agricultural production. The low supply of organic products, despite its ever-increasing demand, suggests that a transition to increased organic production requires a deeper and faster food system reconfiguration, where an array of distinct policies are mobilized and a diversity of actions take place at different levels (Geels, 2018; Pe´er et al, 2019). This paper will attempt to contribute an overall critical assessment of the organic sector´s features and evolution and will identify some of the main obstacles to be overcome, in order to boost the sustainability transition of the agro-food system in Portugal.