The Experts below are selected from a list of 36606 Experts worldwide ranked by ideXlab platform
Jingzhu Zhao - One of the best experts on this subject based on the ideXlab platform.
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nutrient cycling in an alpine tundra ecosystem on changbai mountain northeast china
Applied Soil Ecology, 2006Co-Authors: Gang Wu, Hong-bing Deng, Jingzhu ZhaoAbstract:Nutrient availability regulates the responses of high-latitude ecosystems to climate change but nitrogen, phosphorus and sulfur biogeochemistry, especially, phosphorus and sulfur cycles, are poorly understood in Alpine tundra ecosystem. This study examines the cycling of nutrients in a 302-year-old Alpine tundra ecosystem in which litter has accumulated through compartment methods. Samples of the vegetation, litter and soil components were collected and chemically analyzed for nitrogen (N), phosphorus (P) and sulfur (S). Overall, nutrient budgets for N, P and S pool sizes were determined. Although there were large reserves of N (24,640 kg hm(-2)), P (5860 kg hm(-2)) and S (10,018.7 kg hm(-2)) in soil layers (0-20 cm), the nutrient reserves within the litter and fine roots within surface soil layer (0-10 cm) were well balanced, indicating that a tightly Closed Plant-litter-soil-Plant nutrient cycle was in operation for the cycling of N, P and S. The litter helped the retention of as many nutrients as possible in Alpine tundra system. (c) 2005 Elsevier B.V. All rights reserved.
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nutrient cycling in an alpine tundra ecosystem on changbai mountain northeast china
Applied Soil Ecology, 2006Co-Authors: Jing Wei, Hong-bing Deng, Jingzhu ZhaoAbstract:Nutrient availability regulates the responses of high-latitude ecosystems to climate change but nitrogen, phosphorus and sulfur biogeochemistry, especially, phosphorus and sulfur cycles, are poorly understood in Alpine tundra ecosystem. This study examines the cycling of nutrients in a 302-year-old Alpine tundra ecosystem in which litter has accumulated through compartment methods. Samples of the vegetation, litter and soil components were collected and chemically analyzed for nitrogen (N), phosphorus (P) and sulfur (S). Overall, nutrient budgets for N, P and S pool sizes were determined. Although there were large reserves of N (24,640 kg hm(-2)), P (5860 kg hm(-2)) and S (10,018.7 kg hm(-2)) in soil layers (0-20 cm), the nutrient reserves within the litter and fine roots within surface soil layer (0-10 cm) were well balanced, indicating that a tightly Closed Plant-litter-soil-Plant nutrient cycle was in operation for the cycling of N, P and S. The litter helped the retention of as many nutrients as possible in Alpine tundra system. (c) 2005 Elsevier B.V. All rights reserved.
Hong-bing Deng - One of the best experts on this subject based on the ideXlab platform.
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nutrient cycling in an alpine tundra ecosystem on changbai mountain northeast china
Applied Soil Ecology, 2006Co-Authors: Gang Wu, Hong-bing Deng, Jingzhu ZhaoAbstract:Nutrient availability regulates the responses of high-latitude ecosystems to climate change but nitrogen, phosphorus and sulfur biogeochemistry, especially, phosphorus and sulfur cycles, are poorly understood in Alpine tundra ecosystem. This study examines the cycling of nutrients in a 302-year-old Alpine tundra ecosystem in which litter has accumulated through compartment methods. Samples of the vegetation, litter and soil components were collected and chemically analyzed for nitrogen (N), phosphorus (P) and sulfur (S). Overall, nutrient budgets for N, P and S pool sizes were determined. Although there were large reserves of N (24,640 kg hm(-2)), P (5860 kg hm(-2)) and S (10,018.7 kg hm(-2)) in soil layers (0-20 cm), the nutrient reserves within the litter and fine roots within surface soil layer (0-10 cm) were well balanced, indicating that a tightly Closed Plant-litter-soil-Plant nutrient cycle was in operation for the cycling of N, P and S. The litter helped the retention of as many nutrients as possible in Alpine tundra system. (c) 2005 Elsevier B.V. All rights reserved.
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nutrient cycling in an alpine tundra ecosystem on changbai mountain northeast china
Applied Soil Ecology, 2006Co-Authors: Jing Wei, Hong-bing Deng, Jingzhu ZhaoAbstract:Nutrient availability regulates the responses of high-latitude ecosystems to climate change but nitrogen, phosphorus and sulfur biogeochemistry, especially, phosphorus and sulfur cycles, are poorly understood in Alpine tundra ecosystem. This study examines the cycling of nutrients in a 302-year-old Alpine tundra ecosystem in which litter has accumulated through compartment methods. Samples of the vegetation, litter and soil components were collected and chemically analyzed for nitrogen (N), phosphorus (P) and sulfur (S). Overall, nutrient budgets for N, P and S pool sizes were determined. Although there were large reserves of N (24,640 kg hm(-2)), P (5860 kg hm(-2)) and S (10,018.7 kg hm(-2)) in soil layers (0-20 cm), the nutrient reserves within the litter and fine roots within surface soil layer (0-10 cm) were well balanced, indicating that a tightly Closed Plant-litter-soil-Plant nutrient cycle was in operation for the cycling of N, P and S. The litter helped the retention of as many nutrients as possible in Alpine tundra system. (c) 2005 Elsevier B.V. All rights reserved.
Toyoki Kozai - One of the best experts on this subject based on the ideXlab platform.
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resource use efficiency of Closed Plant production system with artificial light concept estimation and application to Plant factory
Proceedings of the Japan Academy. Series B Physical and biological sciences, 2013Co-Authors: Toyoki KozaiAbstract:Extensive research has recently been conducted on Plant factory with artificial light, which is one type of Closed Plant production system (CPPS) consisting of a thermally insulated and airtight structure, a multi-tier system with lighting devices, air conditioners and fans, a CO2 supply unit, a nutrient solution supply unit, and an environment control unit. One of the research outcomes is the concept of resource use efficiency (RUE) of CPPS. This paper reviews the characteristics of the CPPS compared with those of the greenhouse, mainly from the viewpoint of RUE, which is defined as the ratio of the amount of the resource fixed or held in Plants to the amount of the resource supplied to the CPPS. It is shown that the use efficiencies of water, CO2 and light energy are considerably higher in the CPPS than those in the greenhouse. On the other hand, there is much more room for improving the light and electric energy use efficiencies of CPPS. Challenging issues for CPPS and RUE are also discussed.
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sustainable Plant factory Closed Plant production systems with artificial light for high resource use efficiencies and quality produce
Acta Horticulturae, 2013Co-Authors: Toyoki KozaiAbstract:This paper reviews the reasons why Plant factories with artificial light are recently interested in society, requirements for sustainable Plant factories, the opportunities and challenges involved in the development of the technology and industry, and types of the Plants suitable for Plant factories with artificial light. Sustainable Plant factories need to be designed and operated for producing high quality Plants and transPlants with minimum use of resource and minimum emissions of CO2 and environmental pollutants. For this purpose, the concept of "Closed system" has been proposed, which is a structure with minimum ventilation, covered with thermally insulated opaque walls, containing multi-tiers (or racks) with artificial light sources. Advantages of this system over the greenhouse include: 1) culture period is shortened by 40-50% with uniform growth and high quality produce, 2) annual production capacity per floor area is 100-fold, and 3) percent reductions in resource consumption are considerable. For example, percent reduction is 100% for pesticide and 95% for irrigation water. Electricity consumption for producing one tomato transPlant from a seed is about 300-400 kJ and its cost in Japan is about 1 JPY (0.008 Euro or 1 US cent as of 2011), and is 25 JPY for producing one butter head lettuce from a seed. Methods of developing integrative environmental control and reducing electricity consumption are discussed based mainly on theoretical consideration. Effects of environmental factors on the growth and development are beyond the scope of this paper.
C Stanghellini - One of the best experts on this subject based on the ideXlab platform.
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Plant factories versus greenhouses comparison of resource use efficiency
Agricultural Systems, 2018Co-Authors: Luuk Graamans, E J Baeza, Andy Van Den Dobbelsteen, I Tsafaras, C StanghelliniAbstract:Abstract Research on Closed Plant production systems, such as artificially illuminated and highly insulated Plant factories, has offered perspectives for urban food production but more insight is needed into their resource use efficiency. This paper assesses the potential of this ‘novel’ system for production in harsh climates with either low or high temperatures and solar radiation levels. The performance of Plant factories is compared with cultivation in traditional greenhouses by analysing the use of resources in the production of lettuce. We applied advanced climate models for greenhouses and buildings, coupled with a lettuce model that relates growth to microclimate. This analysis was performed for three different climate zones and latitudes (24–68°N). In terms of energy efficiency, Plant factories (1411 MJ kg−1 dry weight) outperform even the most efficient greenhouse (Sweden with artificial illumination; 1699 MJ kg−1 dry weight). Additionally, Plant factories achieve higher productivity for all other resources (water, CO2 and land area). With respect to purchased energy, however, greenhouses excel as they use freely available solar energy for photosynthesis. The production of 1 kg dry weight of lettuce requires an input of 247 kWhe in a Plant factory, compared to 70, 111, 182 and 211 kWhe in greenhouses in respectively the Netherlands, United Arab Emirates and Sweden (with and without additional artificial illumination). The local scarcity of resources determines the suitability of production systems. Our quantitative analysis provides insight into the effect of external climate on resource productivity in Plant factories and greenhouses. By elucidating the impact of the absence of solar energy, this provides a starting point for determining the economic viability of Plant factories.
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Plant factories crop transpiration and energy balance
Agricultural Systems, 2017Co-Authors: Luuk Graamans, Andy Van Den Dobbelsteen, E Meinen, C StanghelliniAbstract:Population growth and rapid urbanisation may result in a shortage of food supplies for cities in the foreseeable future. Research on Closed Plant production systems, such as Plant factories, has attempted to offer perspectives for robust (urban) agricultural systems. Insight into the explicit role of Plant processes in the total energy balance of these production systems is required to determine their potential. We describe a crop transpiration model that is able to determine the relation between sensible and latent heat exchange, as well as the corresponding vapour flux for the production of lettuce in Closed systems. Subsequently, this model is validated for the effect of photosynthetic photon flux, cultivation area cover and air humidity on lettuce transpiration, using literature research and experiments. Results demonstrate that the transpiration rate was accurately simulated for the aforementioned effects. Thereafter we quantify and discuss the energy productivity of a standardised Plant factory and illustrate the importance of transpiration as a design parameter for climatisation. Our model can provide a greater insight into the energetic expenditure and performance of Closed systems. Consequently, it can provide a starting point for determining the viability and optimisation of Plant factories.
Jing Wei - One of the best experts on this subject based on the ideXlab platform.
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nutrient cycling in an alpine tundra ecosystem on changbai mountain northeast china
Applied Soil Ecology, 2006Co-Authors: Jing Wei, Hong-bing Deng, Jingzhu ZhaoAbstract:Nutrient availability regulates the responses of high-latitude ecosystems to climate change but nitrogen, phosphorus and sulfur biogeochemistry, especially, phosphorus and sulfur cycles, are poorly understood in Alpine tundra ecosystem. This study examines the cycling of nutrients in a 302-year-old Alpine tundra ecosystem in which litter has accumulated through compartment methods. Samples of the vegetation, litter and soil components were collected and chemically analyzed for nitrogen (N), phosphorus (P) and sulfur (S). Overall, nutrient budgets for N, P and S pool sizes were determined. Although there were large reserves of N (24,640 kg hm(-2)), P (5860 kg hm(-2)) and S (10,018.7 kg hm(-2)) in soil layers (0-20 cm), the nutrient reserves within the litter and fine roots within surface soil layer (0-10 cm) were well balanced, indicating that a tightly Closed Plant-litter-soil-Plant nutrient cycle was in operation for the cycling of N, P and S. The litter helped the retention of as many nutrients as possible in Alpine tundra system. (c) 2005 Elsevier B.V. All rights reserved.