L'Emmagatzematge de cereals en sitges d'època ibèrica al nord-est de Catalunya

Una sitja és una cavitat subterrània destinada a emmagatzemar la collita, especialment de cereals. Amb el manteniment d'unes condicions ideal de temperatura i humitat els cereals s'hi poden conservar durant un llarg període de temps, que segons Varró podria arribar als 50 anys. Aquestes excepcionals possibilitats han possibilitat que l'emmagatzematge en sitges fos un dels mètodes de conservació de cereals a llarg termini més utilitzat en les societats pre-industrials de tot el món. La sitja estàndard del nord-est de Catalunya és aquella que era excavada a l'argila, no portava revestiment i tenia la boca en forma de tub, de 0,77 m de diàmetre màxim per 0,42 de profunditat. El perfil era de tipus còncau, amb el diàmetre màxim situat en el terç central de la sitja, i un fons indistintament còncau o pla. La profunditat i el diàmetre màxim es situarien entre 1,75 i 2 m., amb un marge de diferència reduïdíssim entre ambdues mesures. La capacitat resultant d'aquestes dimensions se situaria entre 1 i 3 tones de cereals, que en termes estàndards de producció seria el resultat de la collita d'una extensió d'entre 1,5 i 4 hectàrees de terreny. ASBTRACT: A silo is an underground cavity designed to store the harvest, especially grain. With the maintenance of ideal conditions of temperature and moisture grains can be preserved for a long period of time, according to Varró it could reach 50 years. These exceptional opportunities have enabled the storage silos to be one of the methods of long-term conservation of grain used in most pre-industrial societies around the world. The standard silo from the North-East of Catalonia was excavated in clay,it had no siding and its mouth was tube-shaped, up to 0.77 m of maximum diameter to 0.42 deep. The profile was concave, with maximum diameter located in the central third of the silo, and a background either concave or flat. The depth and maximum diameter are located between 1.75 and 2 m, with a very little margin of difference between the two measures. The capacity resulting from these dimensions would be located between 1 and 3 tons of cereals, which in terms of production standards it would mean a harvest of between 1.5 and 4 hectares of ground.

Analysis of simple hardware efficiency for temperature measurement in agriculture and environment

This work focuses basically on the design and analysis of simple and low cost hardware systems efficiency for temperature measurement in agricultural area. The main objective is to prove quantitatively, through statistical data analysis, to what extent a simple hardware designed with inexpensive components can be used safely in the indoor temperature measurement in farm buildings, such as greenhouses, warehouse or silos. To verify the of simple hardware efficiency, its data were compared with data from measurements with a high performance LabVIEW platform. This work proved that a simple hardware based on a microcontroller and the LM35 sensor can perform well. It presented a good accuracy but a relatively low precision that can be improved when performed some consecutive signal sampling and then used its average value. Although there are many papers that explain these components, this work has the distinction of presenting a data analysis in numerical form and using high performance systems to ensure critical data comparison.

Silage, silage crops and silos /

Mode of access: Internet.

Farm silos /

Originally issued Apr. 1960.

Little Dairy on the Prairie: From Butter-makin' Women to High-tech Agriculture, July 10, 2008

In 2001, extensive archaeological excavations were conducted at the Oneida Cheese Factory in Jones County. The county is a microcosm of larger dairying trends found throughout northeast Iowa, the state's premier dairy-producing region, Jones County moved from homemade cheese and butter production by farm women, to the industrialization of the dairy farm and opening of cheese factories and butter creameries.A number of innovations affected the industry around the turn-of-the-twentieth century, including reliable butterfat testing, the introduction of ensilage (silos) that created year round milk production, and consolidation of the many local creameries into larger creamery organizations, such as the Diamond Creamery run by Henry D. Sherman of Jones County. Iowa's dairy industry of today looks very different from its heritage: consolidation and competition have drastically reduced the number of cows, dairy farms, and processing plants. In recent years, northeast Iowa has become the center of a movement to revitalize Iowa's dairy industry, particularly through the use of value-added strategies, such as niche markets and large regional co-operatives: the lessons from Iowa's dairying legacy are resurfacing as a solution to modern agricultural challenges.

Transforming agriculture through pervasive wireless sensor networks

A large-scale, outdoor, pervasive computing system based on the Fleck hardware platform applies sensor network technology to farming. Comprising static and animal-borne mobile nodes, the system measures the state of a complex, dynamic system comprising climate, soil, pasture, and animals. This data supports prediction of the land's future state and improved management outcomes through closed-loop control. This article is part of a special issue, Building a Sensor-Rich World.

Greenhouse Gas Fluxes in Tropical and Temperae Agriculture: The Need for a Full-Cost Accounting of Global Warming Potentials

Agriculture's contribution to radiative forcing is principally through its historical release of carbon in soil and vegetation to the atmosphere and through its contemporary release of nitrous oxide (N2O) and methane (CHM4). The sequestration of soil carbon in soils now depleted in soil organic matter is a well-known strategy for mitigating the buildup of CO2 in the atmosphere. Less well-recognized are other mitigation potentials. A full-cost accounting of the effects of agriculture on greenhouse gas emissions is necessary to quantify the relative importance of all mitigation options. Such an analysis shows nitrogen fertilizer, agricultural liming, fuel use, N2O emissions, and CH4 fluxes to have additional significant potential for mitigation. By evaluating all sources in terms of their global warming potential it becomes possible to directly evaluate greenhouse policy options for agriculture. A comparison of temperate and tropical systems illustrates some of these options.

Nitrogen fertilizer management for nitrous oxide (N2O) mitigation in intensive corn (Maize) production: an emissions reduction protocol for US Midwest agriculture

Nitrous oxide (N2O) is a major greenhouse gas (GHG) product of intensive agriculture. Fertilizer nitrogen (N) rate is the best single predictor of N2O emissions in row-crop agriculture in the US Midwest. We use this relationship to propose a transparent, scientifically robust protocol that can be utilized by developers of agricultural offset projects for generating fungible GHG emission reduction credits for the emerging US carbon cap and trade market. By coupling predicted N2O flux with the recently developed maximum return to N (MRTN) approach for determining economically profitable N input rates for optimized crop yield, we provide the basis for incentivizing N2O reductions without affecting yields. The protocol, if widely adopted, could reduce N2O from fertilized row-crop agriculture by more than 50%. Although other management and environmental factors can influence N2O emissions, fertilizer N rate can be viewed as a single unambiguous proxy—a transparent, tangible, and readily manageable commodity. Our protocol addresses baseline establishment, additionality, permanence, variability, and leakage, and provides for producers and other stakeholders the economic and environmental incentives necessary for adoption of agricultural N2O reduction offset projects.

Measuring and decomposing changes in agricultural productivity, nitrogen use efficiency and cumulative exergy efficiency: Application to OECD agriculture

This paper uses an aggregate quantity space to decompose the temporal changes in nitrogen use efficiency and cumulative exergy use efficiency into changes of Moorsteen–Bjurek (MB) Total Factor Productivity (TFP) changes and changes in the aggregate nitrogen and cumulative exergy contents. Changes in productivity can be broken into technical change and changes in various efficiency measures such as technical efficiency, scale efficiency and residual mix efficiency. Changes in the aggregate nitrogen and cumulative exergy contents can be driven by changes in the quality of inputs and outputs and changes in the mixes of inputs and outputs. Also with cumulative exergy content analysis, changes in the efficiency in input production can increase or decrease the cumulative exergy transformity of agricultural production. The empirical study in 30 member countries of the Organisation for Economic Co-operation Development from 1990 to 2003 yielded some important findings. The production technology progressed but there were reductions in technical efficiency, scale efficiency and residual mix efficiency levels. This result suggests that the production frontier had shifted up but there existed lags in the responses of member countries to the technological change. Given TFP growth, improvements in nutrient use efficiency and cumulative exergy use efficiency were counteracted by reductions in the changes of the aggregate nitrogen contents ratio and aggregate cumulative exergy contents ratio. The empirical results also confirmed that different combinations of inputs and outputs as well as the quality of inputs and outputs could have more influence on the growth of nutrient and cumulative exergy use efficiency than factors that had driven productivity change. Keywords: Nutrient use efficiency; Cumulative exergy use efficiency; Thermodynamic efficiency change; Productivity growth; OECD agriculture; Sustainability