WorldWideScience

Sample records for plastic greenhouse vegetable

  1. Uptake of di-(2-ethylhexyl) phthalate of vegetables from plastic film greenhouses.

    Science.gov (United States)

    Fu, Xiaowei; Du, Qizhen

    2011-11-09

    Uptake of di-(2-ethylhexyl) phthalate (DEHP) of nine vegetables including potherb mustard, bok choy, celery, spinach, cabbage, leaf of tube, lettuce, garlic, and edible amaranth in plastic film greenhouses with different plastic films, film thickness, greenhouse age, and greenhouse height was studied. The results showed that the higher the DEHP content of film, the thicker the film, the lower the height of the greenhouse, and the younger the age of the greenhouse were, the higher the DEHP concentration of vegetables was. The results afford significant information for production of safe vegetables with low level DEHP contamination.

  2. Occurrence and risk assessment of phthalate esters (PAEs) in vegetables and soils of suburban plastic film greenhouses.

    Science.gov (United States)

    Wang, Jun; Chen, Gangcai; Christie, Peter; Zhang, Manyun; Luo, Yongming; Teng, Ying

    2015-08-01

    Phthalate esters (PAEs) are suspected of having adverse effects on human health and have been frequently detected in soils and vegetables. The present study investigated their occurrence and composition in plastic film greenhouse soil-vegetable systems and assessed their potential health risks to farmers exposed to these widespread pollutants. Six priority control phthalates, namely dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DnBP), butyl benzyl phthalate (BBP), di-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DnOP), were determined in 44 plastic film greenhouse vegetables and corresponding soils. Total PAEs ranged from 0.51 to 7.16mgkg(-1) in vegetables and 0.40 to 6.20mgkg(-1) in soils with average concentrations of 2.56 and 2.23mgkg(-1), respectively. DnBP, DEHP and DnOP contributed more than 90% of the total PAEs in both vegetables and soils but the proportions of DnBP and DnOP in vegetables were significantly (p3.00mgkg(-1) but were greenhouses. Health risks were mainly by exposure through vegetable consumption and soil ingestion.

  3. Phthalate esters contamination in soils and vegetables of plastic film greenhouses of suburb Nanjing, China and the potential human health risk.

    Science.gov (United States)

    Ma, Ting Ting; Wu, Long Hua; Chen, Like; Zhang, Hai Bo; Teng, Ying; Luo, Yong Ming

    2015-08-01

    The contamination of phthalate esters (PAEs) has become a potential threat to the environment and human health because they could be easily released as plasticizers from the daily supply products, especially in polyethylene films. Concentration levels of total six PAEs, nominated as priority pollutants by the US Environmental Protection Agency (USEPA), were investigated in soils and vegetables from four greenhouse areas in suburbs of Nanjing, East China. Total PAEs concentration ranged from 930 ± 840 to 2,450 ± 710 μg kg(-1) (dry weight (DW)) in soil and from 790 ± 630 to 3,010 ± 2,130 μg kg(-1) in vegetables. Higher concentrations of PAEs were found in soils except in Suo Shi (SS) area and in vegetables, especially in potherb mustard and purple tsai-tai samples. Risk assessment mainly based on the exposures of soil ingestion and daily vegetable intake indicated that bis(2-ethylhexyl) phthalate (DEHP) in the samples from Gu Li (GL) and Hu Shu (HS) exhibited the highest hazard to children less than 6-year old. Therefore, the human health risk of the PAEs contamination in soils and vegetables should greatly be of a concern, especially for their environmental estrogen analog effects.

  4. Salt Contents in Soils Under Plastic Greenhouse Gardening in China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Field experiments were conducted on three main soils, brown soil, meadow soil and cinnamon soil, of Shandong Province to study the effect of plastic greenhouse gardening on soil salt contents. As compared to the open fields, the soil nutrient contents in the fields under plastic greenhouse gardening all increased significantly. The organic matter, quickly available N and P increases were extremely significant and the quickly available K increase was also significant. Along with the nutrient increases the soil salt contents increased clearly in all the soils investigated not only in the top layer but also in the deeper layers, being extremely significant in the 0~10 cm layer and significant in the 10~40 cm layers. The salt contents in the plastic greenhouses had significant correlations with the soil available nitrogen and phosphorous. Soils with longer plastic greenhouse gardening time tended to have more salt. The plastic greenhouse soils contained less CO32- and much more NO3- than the open soils, which indicated a higher influence of human intervention in plastic greenhouses. Among the constituent ions, Cl-, NO3-, Ca2+ and Mg2+ had positive while HCO3- had negative significant or extremely significant correlations with total salt, with correlation coefficients being 0.66*, 0.80**, 0.92**, 0.80** and -0.64*, respectively. Nitrate decreased from the top to deeper layers both in the plastic greenhouses and in the open fields. The plastic greenhouse soils contained much more nitrate than the open fields in every layer and even the nitrate contents of the 80~100 cm layer were still several times those of the top layer in the open fields. The main reason for the salt increases was considered to be the inappropriate fertilization and selective absorption of nutrients by plants in the plastic greenhouses. The methods recommended to avoid soil salt increase in the plastic greenhouses were to apply fertilizers rationally according to the soils, vegetables and

  5. “Break the Plastic Film (net) to Protect the Greenhouse Frame”---Active Controls of the Damaging Risk Against Typhoon for the Year-Round Vegetable Greenhouses%“去膜(网)保架”--主动控制常年蔬菜大棚在台风中损坏的风险

    Institute of Scientific and Technical Information of China (English)

    刘建; 庞真真

    2015-01-01

    The frequent typhoon and the investment restrictions lead to poor wind resistance ability of the greenhouse in Hainan, in the case, the greenhouse insurance successive losses makes it difficult to promote. Then the “Break the plastic film (net) to protect the greenhouse frame” is proposed against typhoon for the Year-Round Vegetable Greenhouses. Combination of the greenhouse insurance and the measures of “Break the plastic film (net) to protect the greenhouse frame”, on the one hand, farmers can reduce loss in the face of typhoon and resume production after the disaster in a short term; on the other hand, greenhouse insurance companies can also reduce the risk of insurance and control the insurance payment within reasonable limits. The measurements not only can promote the sustainable development of greenhouse insurance, but also can ensure a stable supply of vegetables after the disaster and reduce greenhouse skeleton material waste with remarkable social significance.%针对海南多台风、设施大棚由于投资限制而导致抗风能力差与大棚保险在频发台风情况下连年亏损、难以积极推广之间的矛盾,提出以常年蔬菜大棚为主要对象的“去膜(网)保架”防台风措施。将大棚保险和“去膜(网)保架”的措施结合起来,使农户在风灾面前降低损失,灾后短期内迅速恢复生产;大棚的保险企业也能够降低保险风险,将保险赔付控制在合理的范围之内,促进大棚保险的可持续发展;另外还能在一定程度上稳定灾后“菜篮子”的供应、降低大棚骨架材料的浪费,具有显著的社会效益。

  6. Intensity of competition in the market of greenhouse vegetables

    Directory of Open Access Journals (Sweden)

    Oleg Ivanovich Botkin

    2012-03-01

    Full Text Available This paper reviews the competitive environment of the market greenhouse vegetables. Revealed specific features of the industry, determining the level of intensity of competition in the market greenhouse vegetables. Classified factors internal and external environment, identify indicators that affect the state of the market. The factors that determine the intensity of competition in the market greenhouse vegetables.The main competitors on the Russian market of greenhouse production.Identified indicators of the intensity level of competition, in particular: the level of monopolization of the market greenhouse vegetables, the level of concentration of production in the industry, the generalized index of the intensity of the competitive environment.Shows a comparative analysis of competitors’ market greenhouse vegetables in Udmurtia.Revealed competitive advantages which can help local producers to reduce the pressure of competition and intra-industry to occupy a leading position in the Russian market of greenhouse vegetable production.The dynamics of economic performance of Russian producers. Ways of improving the competitiveness of enterprises for the production of greenhouse vegetables

  7. Optimizing nitrogen and water inputs for greenhouse vegetable production

    NARCIS (Netherlands)

    Thompson, R.B.; Gallardo, M.; Voogt, W.

    2015-01-01

    Greenhouse vegetable production systems require high N and irrigation inputs. Commonly, these systems are associated with environmental problems caused by nitrate leaching. Given increasing societal pressure to reduce these problems, there is a requirement to optimally use N and water inputs. Opt

  8. Soil Phosphorus status in Chinese greenhouse vegetable production system

    DEFF Research Database (Denmark)

    Kianpoor Kalkhajeh, Yusef

    Rapid expansion of greenhouse vegetable production (GVP) in China within the last three decades has been accompanied with intensive application of chemical and manure fertilizers, frequent irrigation, and year-round crop rotation. As a consequence, excessive P accumulation and availability have...... to the surrounding below threshold values Overall, very high P contents were measured in 75 representative Chinese GVP top soils (0-20 cm) with total P and Olsen P varying from 260 to 11,200 mg kg-1, and 5 to 740 mg kg-1, respectively. These large variations reflect the significant differences in vegetation history...

  9. Analysis of Phthalate Esters in Air, Soil and Plants in Plastic Film Greenhouse

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The phthalate esters such as DMP, DEP, DBP and DEHP in air, soil and plant samples in plastic film greenhouse were clean up with fine silica gel column and determined with HPLC. It was found that the concentrations of PEs in air and soil samples in plastic film greenhouse are much higher than those of contrast samples. But concentrations of PEs in plants in plastic film greenhouse are not remarkably affected by the pollution of air and soil.

  10. Contribution of plastic waste recovery to greenhouse gas (GHG) savings in Spain

    OpenAIRE

    Sevigné Itoiz, Eva; Martínez Gasol, Carles; Rieradevall, Joan; Gabarrell Durany, Xavier

    2015-01-01

    This paper concentrates on the quantification of greenhouse gas (GHG) emissions of post-consumer plastic waste recovery (material or energy) by considering the influence of the plastic waste quality (high or low), the recycled plastic applications (virgin plastic substitution or non-plastic substitution) and the markets of recovered plastic (regional or global). The aim is to quantify the environmental consequences of different alternatives in order to evaluate opportunities and limitations t...

  11. Impact of Drip Irrigation Scheduling on Vegetative Parameters in Tomato (Lycopersicon esculentum Mill. Under Unheated Greenhouse

    Directory of Open Access Journals (Sweden)

    S.M. Alaoui

    2014-01-01

    Full Text Available Grafted Tomatoes were grown on a fine sandy soil using drip irrigation and plastic mulch to evaluate the effects of irrigation scheduling on water requirements and vegetative parameters under typical Massa greenhouses growing conditions. Capacitive sensors were used to automatically schedule irrigations. The result of this study shows that irrigation dose and frequency does not affect stem diameter in grafted tomato plant, no significant effect on leaves number has been observed. But irrigation scheduling have a large effect on root’s development, The root containers results indicated that a water stress equivalent to 50%ETc and 20% frequency can lead to deep root system; that makes possible to sustain a suitable vegetative canopy if doses and frequencies are well managed in a daily scale; It was possible save 50% of irrigation water.

  12. Plastic and Glass Greenhouses Detection and Delineation from WORLDVIEW-2 Satellite Imagery

    Science.gov (United States)

    Koc-San, D.; Sonmez, N. K.

    2016-06-01

    Greenhouse detection using remote sensing technologies is an important research area for yield estimation, sustainable development, urban and rural planning and management. An approach was developed in this study for the detection and delineation of greenhouse areas from high resolution satellite imagery. Initially, the candidate greenhouse patches were detected using supervised classification techniques. For this purpose, Maximum Likelihood (ML), Random Forest (RF), and Support Vector Machines (SVM) classification techniques were applied and compared. Then, sieve filter and morphological operations were performed for improving the classification results. Finally, the obtained candidate plastic and glass greenhouse areas were delineated using boundary tracing and Douglas Peucker line simplification algorithms. The proposed approach was implemented in the Kumluca district of Antalya, Turkey utilizing pan-sharpened WorldView-2 satellite imageries. Kumluca is the prominent district of Antalya with greenhouse cultivation and includes both plastic and glass greenhouses intensively. When the greenhouse classification results were analysed, it can be stated that the SVM classification provides most accurate results and RF classification follows this. The SVM classification overall accuracy was obtained as 90.28%. When the greenhouse boundary delineation results were considered, the plastic greenhouses were delineated with 92.11% accuracy, while glass greenhouses were delineated with 80.67% accuracy. The obtained results indicate that, generally plastic and glass greenhouses can be detected and delineated successfully from WorldView-2 satellite imagery.

  13. Recycling of plastic: accounting of greenhouse gases and global warming contributions

    DEFF Research Database (Denmark)

    Astrup, Thomas; Fruergaard, Thilde; Christensen, Thomas Højlund

    2009-01-01

    Major greenhouse gas (GHG) emissions related to plastic waste recycling were evaluated with respect to three management alternatives: recycling of clean, single-type plastic, recycling of mixed/contaminated plastic, and use of plastic waste as fuel in industrial processes. Source-separated plasti...... to a mixture of different plastic types and/or contamination, the plastic should be used for energy utilization. Recycling of plastic waste for substitution of other materials such as wood provided no savings with respect to global warming....

  14. Interaction between vegetable oil based plasticizer molecules and polyvinyl chloride, and their plasticization effect

    Science.gov (United States)

    Haryono, Agus; Triwulandari, Evi; Jiang, Pingping

    2017-01-01

    Plasticizer molecules are low molecular weight compounds that are widely used in polymer industries especially in polyvinyl chloride (PVC) resin. As an additive in PVC resin, the important role of plasticizer molecules is to improve the flexibility and processability of PVC by lowering the glass transition temperature (Tg). However, the commercial plasticizer like di(2-ethylhexyl)phthalate (DEHP) is known to cause liver cancer, at least in laboratory rats. DEHP can leach out from PVC into blood, certain drug solutions and fatty foods, which has been detected in the bloodstream of patients undergoing transfusion. Vegetable oil based plasticizers have some attractive properties such as non-toxic, bio-degradable, good heat and light stability, renewable resources, and environmentally friendly. Here we discussed the main results and development of vegetable oil based plasticizer, and especially palm oil based plasticizer. The interaction between plasticizer and polymer was discussed from the properties of the plasticized polymeric material.

  15. Greenhouse cultivation mitigates metal-ingestion-associated health risks from vegetables in wastewater-irrigated agroecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Chun [College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, Gansu (China); College of Geography and Environmental Science, Northwest Normal University, Lanzhou 730070, Gansu (China); Chen, Xing-Peng; Ma, Zhen-Bang [College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, Gansu (China); Jia, Hui-Hui [State High-Tech Industrial Innovation Center, Shenzhen 518057, Guangdong (China); Wang, Jun-Jian, E-mail: junjian.wang@utoronto.ca [Department of Physical and Environmental Sciences, University of Toronto, Toronto M1C 1A4 (Canada)

    2016-08-01

    Wastewater irrigation can elevate metal concentrations in soils and crops and increase the metal-associated health risks via vegetable ingestion in arid and semiarid northwestern China. Here, we investigated the As, Cd, Cr, Cu, Ni, Pb, and Zn concentrations in four vegetable species from Dongdagou and Xidagou farmlands in Baiyin, Gansu, China. We evaluated the effects of irrigation type (Dongdagou: industrial wastewater; Xidagou: domestic wastewater) and cultivation mode (open field and greenhouse) on the vegetable metal concentration, metal partitioning, soil-to-plant bioconcentration factor (BCF), and the health risk index. All stream waters, soils, and vegetables were found most severely polluted by As and Cd, with higher severity in the industrial-wastewater-irrigated Dongdagou than the domestic-wastewater-irrigated Xidagou. All vegetables had higher or, at least, comparable metal mass allocated in the shoot than in the root. Greenhouse cultivation could reduce metal-ingestion-associated health risks from edible vegetable biomass by decreasing the soil to plant bioaccumulation (BCF) and the metal concentration. This effect was always significant for all vegetables within Xidagou, and for carrot within Dongdagou. This mitigation effect of greenhouse cultivation could be attributed to the metal sorption by a higher level of soil organic matter and faster growth rate over metal uptake rate in greenhouses compared to open fields. Such mitigation effect was, however, insignificant for leafy vegetables within Dongdagou, when much more severely polluted water for irrigation was applied in greenhouses compared to open fields within Dongdagou. The present study highlights greenhouse cultivation as a potential mitigating approach to providing less-polluted vegetables for residents in the severely polluted area in addition to the source pollution control. - Highlights: • Vegetable farmlands in Baiyin, Gansu, China were severely polluted by As and Cd. • Greenhouses had

  16. Effects of UV-absorbing plastic films on greenhouse whitefly (Homoptera: Aleyrodidae).

    Science.gov (United States)

    Mutwiwa, Urbanus N; Borgemeister, Christian; von Elsner, Burkhard; Tantau, Hans-Juergen

    2005-08-01

    Studies were conducted to investigate the effects of ultraviolet (UV)-absorbing plastic films on the orientation and distribution behavior of the greenhouse whitefly, Trialeurodes vaporariorum (Westwood). In field experiments, small tunnels were constructed and covered with either an UV-transmitting (Thermilux) or UV-absorbing (K-Rose) plastic film. Results show that significantly more whiteflies were recorded in the tunnels with high compared with those with low UV intensities. Moreover, whitefly penetration and dispersion were less inside the UV-deficient tunnels. These results suggest that the type of plastic film used for greenhouse covers may have a significant influence on both the initial immigration and distribution of T. vaporariorum into greenhouses. The possibilities of using UV-absorbing plastic films for whitefly integrated pest management in greenhouses are discussed.

  17. Heavy metals in intensive greenhouse vegetable production systems along Yellow Sea of China

    DEFF Research Database (Denmark)

    Hu, Wenyou; Huang, Biao; Tian, Kang;

    2017-01-01

    Recently, greenhouse vegetable production (GVP) has grown rapidly and counts a large proportion of vegetable production in China. In this study, the accumulation, health risk and threshold values of selected heavy metals were evaluated systematically. A total of 120 paired soil and vegetable samp...

  18. [Effects of fertilizer application on greenhouse vegetable yield: a case study of Shouguang].

    Science.gov (United States)

    Liu, Ping; Li, Yan; Jiang, Li-Hua; Liu, Zhao-Hui; Gao, Xin-Hao; Lin, Hai-Tao; Zheng, Fu-Li; Shi, Jing

    2014-06-01

    Data collected from 51 representative greenhouses of Shouguang through questionnaire survey were analyzed to investigate the effect of chemical fertilizers on vegetable yield, relationship between application of organic manure and yield, and influence factors and evolution rule of fertilizer application rate. The results showed that averages of 3338 kg N x hm(-2), 1710 kg P2O5 x hm(-2) 3446 kg K2O x hm(-2) were applied to greenhouse vegetables annually in Shouguang, 6-14 times as that in the local wheat-maize rotation system. The application rates of chemical N, P, and K fertilizers accounted for about 35%, 49% and 42% of the total input. Increasing application of chemical fertilizers had no significant effect on vegetable yields, while organic manure input significantly increased the vegetable yields. With the increase of greenhouse cultivating time, no significant changes in the input of chemical N, P, and K fertilizers were observed in greenhouse vegetable production while organic manure input decreased significantly. Differences in vegetable species, planting pattern and cultivating time of greenhouses was one of the reasons for large variations in nutrient application rate. In recent more than ten years, organic manure nutrient input increased significantly, chemical N and P fertilizer input presented a downward trend, chemical K fertilizer input increased significantly, and the N/P/K ratio became more and more reasonable in greenhouse vegetable production in Shouguang.

  19. [Effects of superphosphate addition on NH3 and greenhouse gas emissions during vegetable waste composting].

    Science.gov (United States)

    Yang, Yan; Sun, Qin-ping; Li, Ni; Liu, Chun-sheng; Li, Ji-jin; Liu, Ben-sheng; Zou, Guo-yuan

    2015-01-01

    To study the effects of superphosphate (SP) on the NH, and greenhouse gas emissions, vegetable waste composting was performed for 27 days using 6 different treatments. In addition to the controls, five vegetable waste mixtures (0.77 m3 each) were treated with different amounts of the SP additive, namely, 5%, 10%, 15%, 20% and 25%. The ammonia volatilization loss and greenhouse gas emissions were measured during composting. Results indicated that the SP additive significantly decreased the ammonia volatilization and greenhouse gas emissions during vegetable waste composting. The additive reduced the total NH3 emission by 4.0% to 16.7%. The total greenhouse gas emissions (CO2-eq) of all treatments with SP additives were decreased by 10.2% to 20.8%, as compared with the controls. The NH3 emission during vegetable waste composting had the highest contribution to the greenhouse effect caused by the four different gases. The amount of NH3 (CO2-eq) from each treatment ranged from 59.90 kg . t-1 to 81.58 kg . t-1; NH3(CO2-eq) accounted for 69% to 77% of the total emissions from the four gases. Therefore, SP is a cost-effective phosphorus-based fertilizer that can be used as an additive during vegetable waste composting to reduce the NH3 and greenhouse gas emissions as well as to improve the value of compost as a fertilizer.

  20. Greenhouse cultivation mitigates metal-ingestion-associated health risks from vegetables in wastewater-irrigated agroecosystems.

    Science.gov (United States)

    Cao, Chun; Chen, Xing-Peng; Ma, Zhen-Bang; Jia, Hui-Hui; Wang, Jun-Jian

    2016-08-01

    Wastewater irrigation can elevate metal concentrations in soils and crops and increase the metal-associated health risks via vegetable ingestion in arid and semiarid northwestern China. Here, we investigated the As, Cd, Cr, Cu, Ni, Pb, and Zn concentrations in four vegetable species from Dongdagou and Xidagou farmlands in Baiyin, Gansu, China. We evaluated the effects of irrigation type (Dongdagou: industrial wastewater; Xidagou: domestic wastewater) and cultivation mode (open field and greenhouse) on the vegetable metal concentration, metal partitioning, soil-to-plant bioconcentration factor (BCF), and the health risk index. All stream waters, soils, and vegetables were found most severely polluted by As and Cd, with higher severity in the industrial-wastewater-irrigated Dongdagou than the domestic-wastewater-irrigated Xidagou. All vegetables had higher or, at least, comparable metal mass allocated in the shoot than in the root. Greenhouse cultivation could reduce metal-ingestion-associated health risks from edible vegetable biomass by decreasing the soil to plant bioaccumulation (BCF) and the metal concentration. This effect was always significant for all vegetables within Xidagou, and for carrot within Dongdagou. This mitigation effect of greenhouse cultivation could be attributed to the metal sorption by a higher level of soil organic matter and faster growth rate over metal uptake rate in greenhouses compared to open fields. Such mitigation effect was, however, insignificant for leafy vegetables within Dongdagou, when much more severely polluted water for irrigation was applied in greenhouses compared to open fields within Dongdagou. The present study highlights greenhouse cultivation as a potential mitigating approach to providing less-polluted vegetables for residents in the severely polluted area in addition to the source pollution control.

  1. Characteristics of nitrogen balance in open-air and greenhouse vegetable cropping systems of China.

    Science.gov (United States)

    Ti, Chaopu; Luo, Yongxia; Yan, Xiaoyuan

    2015-12-01

    Nitrogen (N) loss from vegetable cropping systems has become a significant environmental issue in China. In this study, estimation of N balances in both open-air and greenhouse vegetable cropping systems in China was established. Results showed that the total N input in open-air and greenhouse vegetable cropping systems in 2010 was 5.44 and 2.60 Tg, respectively. Chemical fertilizer N input in the two cropping systems was 201 kg N ha(-1) per season (open-air) and 478 kg N ha(-1) per season (greenhouse). The N use efficiency (NUE) was 25.9 ± 13.3 and 19.7 ± 9.4% for open-air and greenhouse vegetable cropping systems, respectively, significantly lower than that of maize, wheat, and rice. Approximately 30.6% of total N input was accumulated in soils and 0.8% was lost by ammonia volatilization in greenhouse vegetable system, while N accumulation and ammonia volatilization accounted for 19.1 and 11.1%, respectively, of total N input in open-air vegetable systems.

  2. Warming effects on greenhouse gas fluxes in peatlands are modulated by vegetation composition.

    Science.gov (United States)

    Ward, Susan E; Ostle, Nicholas J; Oakley, Simon; Quirk, Helen; Henrys, Peter A; Bardgett, Richard D

    2013-10-01

    Understanding the effects of warming on greenhouse gas feedbacks to climate change represents a major global challenge. Most research has focused on direct effects of warming, without considering how concurrent changes in plant communities may alter such effects. Here, we combined vegetation manipulations with warming to investigate their interactive effects on greenhouse gas emissions from peatland. We found that although warming consistently increased respiration, the effect on net ecosystem CO2 exchange depended on vegetation composition. The greatest increase in CO2 sink strength after warming was when shrubs were present, and the greatest decrease when graminoids were present. CH4 was more strongly controlled by vegetation composition than by warming, with largest emissions from graminoid communities. Our results show that plant community composition is a significant modulator of greenhouse gas emissions and their response to warming, and suggest that vegetation change could alter peatland carbon sink strength under future climate change.

  3. Microclimatic changes caused by different plastic coverings in greenhouses cultivated with cherry tomato in southern Brazil

    Directory of Open Access Journals (Sweden)

    Ester Holcman

    2015-06-01

    Full Text Available In regions with intense solar radiation it is common the use of aluminated covers in greenhouses, with the aim of reducing the inside temperature. However, the use of these covers reduces photosynthetic active radiation (PAR transmitted into the greenhouse. The objective of the present study was to evaluate the influence of different covers on microclimate in greenhouses cultivated with cherry tomato during three growing seasons. The environment I was covered with plastic film anti-UV and with thermo-reflective screen (40% disposed internally. The environment II was covered with diffusive plastic film (55%. The transmitted solar radiation to the interior of covered environments was, on average, 5.5 MJ m-2 day-1 in the environment I and 8.2 MJ m-2 day-1 in environment II. The air temperature in environment II was, on average, 1°C higher than external conditions. The highest difference for the relative humidity (RH was also observed between environment II and the outside conditions, with 10.7% for the minimum RH during the first growing period. Considering all growing periods, the diffusive plastic film provided higher solar energy availability inside the greenhouse than the plastic film with thermo-reflective screen, without causing major changes in air temperature and relative humidity, and promoting greater productivity of tomato grown under this environment for the three periods evaluated.

  4. Arsenic uptake and speciation in vegetables grown under greenhouse conditions.

    Science.gov (United States)

    Smith, E; Juhasz, A L; Weber, J

    2009-04-01

    The accumulation of arsenic (As) by vegetables is a potential human exposure pathway. The speciation of As in vegetables is an important consideration due to the varying toxicity of different As species. In this study, common Australian garden vegetables were hydroponically grown with As-contaminated irrigation water to determine the uptake and species of As present in vegetable tissue. The highest concentrations of total As were observed in the roots of all vegetables and declined in the aerial portions of the plants. Total As accumulation in the edible portions of the vegetables decreased in the order radish > mung bean > lettuce = chard. Arsenic was present in the roots of radish, chard, and lettuce as arsenate (As(V)) and comprised between 77 and 92% of the total As present, whereas in mung beans, arsenite (As(III)) comprised 90% of the total As present. In aerial portions of the vegetables, As was distributed equally between both As(V) and As(III) in radish and chard but was present mainly as As(V) in lettuce. The presence of elevated As in vegetable roots suggests that As species may be complexed by phytochelatins, which limits As translocation to aerial portions of the plant.

  5. Recycling of plastic: accounting of greenhouse gases and global warming contributions.

    Science.gov (United States)

    Astrup, Thomas; Fruergaard, Thilde; Christensen, Thomas H

    2009-11-01

    Major greenhouse gas (GHG) emissions related to plastic waste recycling were evaluated with respect to three management alternatives: recycling of clean, single-type plastic, recycling of mixed/contaminated plastic, and use of plastic waste as fuel in industrial processes. Source-separated plastic waste was received at a material recovery facility (MRF) and processed for granulation and subsequent downstream use. In the three alternatives, plastic was assumed to be substituting virgin plastic in new products, wood in low-strength products (outdoor furniture, fences, etc.), and coal or fuel oil in the case of energy utilization. GHG accounting was organized in terms of indirect upstream emissions (e.g. provision of energy, fuels, and materials), direct emissions at the MRF (e.g. fuel combustion), and indirect downstream emissions (e.g. avoided emissions from production of virgin plastic, wood, or coal/oil). Combined, upstream and direct emissions were estimated to be roughly between 5 and 600 kg CO(2)-eq. tonne( -1) of plastic waste depending on treatment at the MRF and CO(2) emissions from electricity production. Potential downstream savings arising from substitution of virgin plastic, wood, and energy fuels were estimated to be around 60- 1600 kg CO(2)-eq. tonne( -1) of plastic waste depending on substitution ratios and CO(2) emissions from electricity production. Based on the reviewed data, it was concluded that substitution of virgin plastic should be preferred. If this is not viable due to a mixture of different plastic types and/or contamination, the plastic should be used for energy utilization. Recycling of plastic waste for substitution of other materials such as wood provided no savings with respect to global warming.

  6. Contribution of plastic waste recovery to greenhouse gas (GHG) savings in Spain.

    Science.gov (United States)

    Sevigné-Itoiz, Eva; Gasol, Carles M; Rieradevall, Joan; Gabarrell, Xavier

    2015-12-01

    This paper concentrates on the quantification of greenhouse gas (GHG) emissions of post-consumer plastic waste recovery (material or energy) by considering the influence of the plastic waste quality (high or low), the recycled plastic applications (virgin plastic substitution or non-plastic substitution) and the markets of recovered plastic (regional or global). The aim is to quantify the environmental consequences of different alternatives in order to evaluate opportunities and limitations to select the best and most feasible plastic waste recovery option to decrease the GHG emissions. The methodologies of material flow analysis (MFA) for a time period of thirteen years and consequential life cycle assessment (CLCA) have been integrated. The study focuses on Spain as a representative country for Europe. The results show that to improve resource efficiency and avoid more GHG emissions, the options for plastic waste management are dependent on the quality of the recovered plastic. The results also show that there is an increasing trend of exporting plastic waste for recycling, mainly to China, that reduces the GHG benefits from recycling, suggesting that a new focus should be introduced to take into account the split between local recycling and exporting.

  7. Phosphorus saturation and mobilization in two typical Chinese greenhouse vegetable soils

    DEFF Research Database (Denmark)

    Kalkhajeh, Yusef Kianpoor; Huang, Biao; Hu, Wenyou;

    2017-01-01

    and sandy and alkaline Tongshan Ustic Cambosols. A total of 20 intact soil columns were collected based on differences in total P content varying between 1360 and 11,220 mg kg(-1). Overall, six leaching experiments were carried out with collection of leachates over 24 h. Very high P concentrations.......44% led to DRP leaching exceeding 0.1 mg L(-1). Accordingly, more than 80% of Tongshan soils resulted in DRP leaching exceeding the environmental P threshold. In conclusion P rich alkaline sandy soils used for greenhouse vegetable production are at high risk of P mobilization across China.......Chinese greenhouse vegetable production can cause eutrophication of fresh waters due to heavy use of fertilizers. To address this, phosphorus (P) leaching was compared between two major greenhouse vegetable soils from Jiangsu Province, Southeast China: clayey and acid-neutral Guli Orthic Anthrosols...

  8. Evaluation of endosulfan residues in vegetables grown in greenhouses.

    Science.gov (United States)

    Arrebola, F J; Egea-González, F J; Moreno, M; Fernández-Gutiérrez, A; Hernández-Torres, M E; Martínez-Vidal, J L

    2001-07-01

    The reduction in residue levels of endosulfan with time after treatment of tomatoes, green beans, peppers and cucumbers grown in different types of commercial greenhouses (flat- and asymmetric-roof greenhouses) in Almería (Spain) was investigated. A study of the major and minor degradation products of endosulfan in peppers and cucumbers (endosulfan-sulfate, -ether and -lactone) was carried out using gas chromatography-tandem mass spectrometry (GC-MS/MS). To establish the influence of environmental conditions on the degradation of endosulfan, several field trials have been carried out in which crops were sprayed at different rates (full, half- and quarter- of those rates recommended) during two seasons (spring and winter). For statistical purposes, the disappearance of endosulfan with time was considered to follow a pseudo-first-order reaction. Analysis of variance (ANOVA) has been applied to the results obtained. Half-lives of residue disappearance were 4.03-4.68 days in green beans, 4.03-4.20 days in tomatoes, 8.22 days in peppers and 7.97 days in cucumbers. Half-lives in spring were shorter than in the winter season. The application rate and the type of greenhouse did not influence the half-lives.

  9. Optimum Returns from Greenhouse Vegetables under Water Quality and Risk Constraints in the United Arab Emirates

    Directory of Open Access Journals (Sweden)

    Eihab Fathelrahman

    2017-04-01

    Full Text Available Greenhouses have been used in the United Arab Emirates (UAE to produce vegetables that contribute toward UAE food security, including offering fresh vegetable produce in the off-season. However, to manage such greenhouses, farmers face both technical and environmental limitations (i.e., high water scarcity, as well as vegetable market price instability. The objective of this study is to explore tradeoffs between returns (i.e., gross margin of selected vegetables (tomato, pepper, and cucumber, risk (deviation from gross margin means, and an environmental constraint (water salinity using a unique target MOTAD (minimization of total absolute deviations approach to support UAE farmer decision-making processes. The optimal target MOTAD solution included all three vegetables and no corner solution. The results showed tradeoffs between returns and risks, and confirmed that product diversification reduces overall risk. The analysis was consistent with farmer perceptions based on a survey of 78 producers in the region. The search for the optimal mix of vegetable production under UAE greenhouse conditions revealed that reduction in tomato production should be offset by an increase in cucumber production while maintaining a constant level of pepper production. In other words, risk is reduced as cucumber production increases due to the high level of tomato and lettuce price volatility as the alternative to cucumber. The results also demonstrated the importance of the water salinity environmental constraint, as it was found to have a positive marginal value in the optimal vegetable mix solution (i.e., important factor. Thus the optimal solution was highly sensitive to changes in the crop water salinity constraint. The study results also demonstrate that the target MOTAD approach is a suitable optimization methodology. As a practical approach, a decision-maker in the UAE can consider gross margin (total revenue-variable costs maximization with risk and water

  10. EFFECT OF SOIL SOLARIZATION ON THERMAL REGIME OF PLASTIC GREENHOUSE SOIL

    OpenAIRE

    Nereu Augusto Streck; Flavio Miguel Schneider; Galileo Adeli Buriol

    1994-01-01

    SUMMARY Temperature modification in soil of plastic greenhouse caused by solarization was measured during the summer in the Subtropical Central Region of the Rio Grande do Sul State, Brazil. The experiment was carried out in a 10m x 25m greenhouse covered with low density transparent polyethylene (PE). Four 6m x 4m plots were mulched with 100µm thickness PE sheets, from December 12, 1992 to March 7, 1993. Four other plots (same size) without the cover were used as control (bare soil). Results...

  11. Greenhouse vegetable production in The Netherlands and Switzerland: A grounded look at sector competitiveness

    NARCIS (Netherlands)

    Mann, S.; Breukers, A.; Schweiger, J.; Mack, G.

    2011-01-01

    Purpose – The purpose of this paper is to develop a theory that is sufficiently adapted to sector competitiveness. The case of greenhouse vegetable production in The Netherlands and Switzerland is used to explain differences in sector competitiveness. Design/methodology/approach – Interviews focusin

  12. Sustainability of greenhouse fruit vegetables; Spain versus The Netherlands; Development of a monitoring system

    NARCIS (Netherlands)

    Velden, van der N.J.A.

    2004-01-01

    Sustainability is becoming more and more important in the competitive battle between the greenhouse-grown fruiting vegetables produced in Spain and the Netherlands. A monitoring system has been developed. Sustainability is a broad concept regarding primary producers and other links in the chain. How

  13. Greenhouse vegetable production in The Netherlands and Switzerland: A grounded look at sector competitiveness

    NARCIS (Netherlands)

    Mann, S.; Breukers, A.; Schweiger, J.; Mack, G.

    2011-01-01

    Purpose – The purpose of this paper is to develop a theory that is sufficiently adapted to sector competitiveness. The case of greenhouse vegetable production in The Netherlands and Switzerland is used to explain differences in sector competitiveness. Design/methodology/approach – Interviews focusin

  14. Greenhouse gas mitigation for U.S. plastics production: energy first, feedstocks later

    Science.gov (United States)

    Posen, I. Daniel; Jaramillo, Paulina; Landis, Amy E.; Griffin, W. Michael

    2017-03-01

    Plastics production is responsible for 1% and 3% of U.S. greenhouse gas (GHG) emissions and primary energy use, respectively. Replacing conventional plastics with bio-based plastics (made from renewable feedstocks) is frequently proposed as a way to mitigate these impacts. Comparatively little research has considered the potential for green energy to reduce emissions in this industry. This paper compares two strategies for reducing greenhouse gas emissions from U.S. plastics production: using renewable energy or switching to renewable feedstocks. Renewable energy pathways assume all process energy comes from wind power and renewable natural gas derived from landfill gas. Renewable feedstock pathways assume that all commodity thermoplastics will be replaced with polylactic acid (PLA) and bioethylene-based plastics, made using either corn or switchgrass, and powered using either conventional or renewable energy. Corn-based biopolymers produced with conventional energy are the dominant near-term biopolymer option, and can reduce industry-wide GHG emissions by 25%, or 16 million tonnes CO2e/year (mean value). In contrast, switching to renewable energy cuts GHG emissions by 50%–75% (a mean industry-wide reduction of 38 million tonnes CO2e/year). Both strategies increase industry costs—by up to 85/tonne plastic (mean result) for renewable energy, and up to 3000 tonne‑1 plastic for renewable feedstocks. Overall, switching to renewable energy achieves greater emission reductions, with less uncertainty and lower costs than switching to corn-based biopolymers. In the long run, producing bio-based plastics from advanced feedstocks (e.g. switchgrass) and/or with renewable energy can further reduce emissions, to approximately 0 CO2e/year (mean value).

  15. Mapping plastic greenhouse with medium spatial resolution satellite data: Development of a new spectral index

    Science.gov (United States)

    Yang, Dedi; Chen, Jin; Zhou, Yuan; Chen, Xiang; Chen, Xuehong; Cao, Xin

    2017-06-01

    Plastic greenhouses (PGs) are an important agriculture development technique to protect and control the growing environment for food crops. The extensive use of PGs can change the agriculture landscape and affects the local environment. Accurately mapping and estimating the coverage of PGs is a necessity to the strategic planning of modern agriculture. Unfortunately, PG mapping over large areas is methodologically challenging, as the medium spatial resolution satellite imagery (such as Landsat data) used for analysis lacks spatial details and spectral variations. To fill the gap, the paper proposes a new plastic greenhouse index (PGI) based on the spectral, sensitivity, and separability analysis of PGs using medium spatial resolution images. In the context of the Landsat Enhanced Thematic Mapper Plus (ETM+) imagery, the paper examines the effectiveness and capability of the proposed PGI. The results indicate that PGs in Landsat ETM+ image can be successfully detected by the PGI if the PG fraction is greater than 12% in a mixed pixel. A kappa coefficient of 0.83 and overall accuracy of 91.2% were achieved when applying the proposed PGI in the case of Weifang District, Shandong, China. These results show that the proposed index can be applied to identifying transparent PGs in atmospheric corrected Landsat image and has the potential for the digital mapping of plastic greenhouse coverage over a large area.

  16. The effect of floating vegetation on denitrification and greenhouse gas production in wetland mesocosms

    Science.gov (United States)

    Jacobs, A. E.; Harrison, J. A.

    2012-12-01

    Anthropogenic intensification of nitrogen (N) loading to aquatic ecosystems is widespread and can lead to the degradation of these systems. Wetlands are important sites for N removal via denitrification, the microbially mediated reduction of reactive nitrate to inert N2 gas, but they can also produce high levels of greenhouse gases. Floating plants play an important role in encouraging denitrification, since they create low oxygen conditions that may favor denitrification. We investigated whether wetland sediments with floating plant cover had higher denitrification and greenhouse gas production rates than wetland sediments without floating plants. Replicate flow-through mesocosms with wetland sediment and water were constructed in a growth chamber to mimic the wetland where the sediment and water were collected. Mesocosm treatments were covered with floating vegetation (duckweed), an opaque tarp, or no cover to determine how cover type affects denitrification and greenhouse gas production and whether biotic or abiotic factors are likely responsible for observed differences. Denitrification and greenhouse gas production rates were calculated by measuring excess N2 gas, methane, and nitrous oxide concentrations in the water column and measuring the gas exchange rates between the water column and the atmosphere. Gas exchange rates were measured using an inert volatile tracer added to the water column and accumulation of gas in the mesocosm headspace. Additional mesocosm experiments were performed to determine how duckweed-dominated wetland systems respond to nitrogen loading and which mechanism for lowering dissolved oxygen concentrations is important in affecting denitrification under floating vegetation. Mesocosms with floating vegetation had lower dissolved oxygen than no cover or tarp-covered mesocosms, which is consistent with field and literature observations. Water flowing out of the mesocosms had statistically lower total nitrogen and nitrate concentrations

  17. Logistic Equation and its Application as Forecasting Model of Vegetables Production in Greenhouses in Albania

    Directory of Open Access Journals (Sweden)

    VALENTINA SHEHU

    2015-10-01

    Full Text Available Correct forecasting is of a great importance for the business and economy of the country. To comprehend the market and the economic system, mathematical models are used to describe and predict the future of situation. Agriculture is the spinal column of Albania’s economic activity and the last 20 years free market experience has given a demonstration of the high correlation between agricultural progress and the economic development. Producing greenhouse-grown vegetables can result a beneficial activity, but it is a hard and complicated investment. The greenhouse technology is one of great innovation in agriculture. Agricultures methods must be combined with technical knowledge, marketing must be planned before harvest, and every phase of process should be well-managed. In this paper it is studied and applied the logistic growth model for forecasting the production of vegetables in greenhouse. The results of this paper show that the logistic S-shaped curve is a mathematical model to characterize the progress of innovation in agriculture. Also, the logistic equation can be used to describe and predict the production of vegetables in greenhouses in Albania.

  18. GREENHOUSE PLASTIC FILMS CAPABLE OF MODIFYING THE SPECTRAL DISTRIBUTION OF SOLAR RADIATION

    Directory of Open Access Journals (Sweden)

    Evelia Schettini

    2010-03-01

    Full Text Available The aim of this paper was to investigate the radiometric properties of innovative covering films for protected cultivation capable of modifying the spectral distribution of the transmitted radiation and thus the vegetative activity. Two photoselective films, three photoluminescent films and one low-density polyethylene film were used as greenhouse coverings for cherry trees and peach trees, grown in pots. The photoselective films were characterised by a reduction of the R/FR ratio in comparison to the natural solar radiation. Tree growth parameters, such as the apical shoot of cherry trees and the shoot of peach trees, were monitored. Different responses to vegetative activities were observed under the films, depending on the species, with a higher shoots growth rate in the peach with respect to the cherry. The photoselective film characterised by the lowest R/FR ratio significantly enhanced the growth of cherry and peach trees in comparison to the trees cultivated under the other greenhouse films

  19. The Potential Research of Catch Crop in Decrease Soil Nitrate Under Greenhouse Vegetable Production

    Directory of Open Access Journals (Sweden)

    YIN Xing

    2015-06-01

    Full Text Available In order to clarify the impact of catch crops on greenhouse vegetable soil nitrate, explore the mechanism of barrier and controll soil nitrogen leaching losses in greenhouse, and provide a theoretical basis for control nitrogen leaching and prevention of groundwater pollution, this study selected the traditional greenhouse vegetable rotation system in North China plain as research subjects, using field situ remediation technologies on deep-root planting catch crops in the vegetable fallow period by sweet corn, Achyranthes bidentata and white Chrysanthemum. The results showed that: nitrogen content and nitrogen uptake of sweet corn and sweet corn with Achyranthes bidentata intercropping were the highest, respectively 20.11 t·hm-2, 19.62 t·hm-2 and 240.34 kg·hm-2, 287.56 kg·hm-2, significantly higher than white Chrysanthemum. The density of root length and root dry weight decreased with soil depth in the profiles, root length density was demonstrated in order as: intercropping sweet corn> sweet corn> white Chrysanthemum> intercropping Achyranthes bidentata blume. The reduction of NO3--N of sweet corn reached 907.87 kg·hm-2 in soil profile 0~200 cm, significantly higher than sweet corn and hyssop intercropping and white Chrysanthemums. In the interim period of vegetable crop rotation, planting catch crops could effectively reduce nitrate accumulation in the soil, control the soil profile nitrate leaching down.

  20. Characterization of Soil Suppressiveness to Root-Knot Nematodes in Organic Horticulture in Plastic Greenhouse.

    Science.gov (United States)

    Giné, Ariadna; Carrasquilla, Marc; Martínez-Alonso, Maira; Gaju, Núria; Sorribas, Francisco J

    2016-01-01

    The fluctuation of Meloidogyne population density and the percentage of fungal egg parasitism were determined from July 2011 to July 2013 in two commercial organic vegetable production sites (M10.23 and M10.55) in plastic greenhouses, located in northeastern Spain, in order to know the level of soil suppressiveness. Fungal parasites were identified by molecular methods. In parallel, pot tests characterized the level of soil suppressiveness and the fungal species growing from the eggs. In addition, the egg parasitic ability of 10 fungal isolates per site was also assessed. The genetic profiles of fungal and bacterial populations from M10.23 and M10.55 soils were obtained by Denaturing Gradient Gel Electrophoresis (DGGE), and compared with a non-suppressive soil (M10.33). In M10.23, Meloidogyne population in soil decreased progressively throughout the rotation zucchini, tomato, and radish or spinach. The percentage of egg parasitism was 54.7% in zucchini crop, the only one in which eggs were detected. Pochonia chlamydosporia was the only fungal species isolated. In M10.55, nematode densities peaked at the end of the spring-summer crops (tomato, zucchini, and cucumber), but disease severity was lower than expected (0.2-6.3). The percentage of fungal egg parasitism ranged from 3 to 84.5% in these crops. The results in pot tests confirmed the suppressiveness of the M10.23 and M10.55 soils against Meloidogyne. The number of eggs per plant and the reproduction factor of the population were reduced (P < 0.05) in both non-sterilized soils compared to the sterilized ones after one nematode generation. P. chlamydosporia was the only fungus isolated from Meloidogyne eggs. In in vitro tests, P. chlamydosporia isolates were able to parasitize Meloidogyne eggs from 50 to 97% irrespective of the site. DGGE fingerprints revealed a high diversity in the microbial populations analyzed. Furthermore, both bacterial and fungal genetic patterns differentiated suppressive from non

  1. Characterization of soil suppressiveness to root-knot nematodes in organic horticulture in plastic greenhouse

    Directory of Open Access Journals (Sweden)

    Ariadna eGiné

    2016-02-01

    Full Text Available The fluctuation of Meloidogyne population density and the percentage of fungal egg parasitism were determined from July 2011 to July 2013 in two commercial organic vegetable production sites (M10.23 and M10.55 in plastic greenhouses, located in northeastern Spain, in order to know the level of soil suppressiveness. Fungal parasites were identified by molecular methods. In parallel, pot tests characterized the level of soil suppressiveness and the fungal species growing from the eggs. In addition, the egg parasitic ability of ten fungal isolates per site was also assessed. The genetic profiles of fungal and bacterial populations from M10.23 and M10.55 soils were obtained by Denaturing Gradient Gel Electrophoresis (DGGE, and compared with a non-suppressive soil (M10.33. In M10.23, Meloidogyne population in soil decreased progressively throughout the rotation zucchini, tomato, and radish or spinach. The percentage of egg parasitism was 54.7% in zucchini crop, the only one in which eggs were detected. Pochonia chlamydosporia was the only fungal species isolated. In M10.55, nematode densities peaked at the end of the spring-summer crops (tomato, zucchini, and cucumber, but disease severity was lower than expected (0.2 to 6.3. The percentage of fungal egg parasitism ranged from 3 to 84.5% in these crops. The results in pot tests confirmed the suppressiveness of the M10.23 and M10.55 soils against Meloidogyne. The number of eggs per plant and the reproduction factor of the population were reduced (P < 0.05 in both non-sterilized soils compared to the sterilized ones after one nematode generation. Pochonia chlamydosporia was the only fungus isolated from Meloidogyne eggs. In in vitro tests, P. chlamydosporia isolates were able to parasitize Meloidogyne eggs from 50 to 97% irrespective of the site. DGGE fingerprints revealed a high diversity in the microbial populations analyzed. Furthermore, both bacterial and fungal genetic patterns differentiated

  2. Dissipation of chlorpyrifos in pakchoi-vegetated soil in a greenhouse

    Institute of Scientific and Technical Information of China (English)

    FANG Hua; YU Yun-long; WANG Xiao; SHAN Min; WU Xiao-mao; YU Jing-quan

    2006-01-01

    The dissipation of chlorpyrifos in pakchoi-vegetated soil was investigated in the summer and autumn in a greenhouse and field, respectively. The dissipation of chlorpyrifos in pakchoi-grown soil was comparatively described by fitting the residue data to seven models (1st-order, 1.5th-order, 2nd-order, RF 1st-order, RF 1.5th-order, RF 2nd-order, and bi-exponential or two-compartment models). Statistical analysis was performed using the SPSS 11.5 statistical package. The bi-exponential model was selected as the optimal model according to the coefficient of determination r2. The dissipation half-lives (DT50) of chlorpyrifos in pakchoi-vegetated soil at the recommended dose in the summer and autumn, calculated by the bi-exponential model, were 0.6 and 1.2 d in a greenhouse,0.4 and 1.0 d in a field, respectively; the corresponding values at double dose were 1.2 and 2.1 d in a greenhouse, 0.5 and 1.3 d in a field, respectively. The kinetic data indicate the dissipation of chlorpyrifos in pakchoi-grown soil in a greenhouse is slower than that in a field, and dissipates slower in the autumn than in the summer.

  3. Phthalic acid esters in soils from vegetable greenhouses in Shandong Peninsula, East China.

    Science.gov (United States)

    Chai, Chao; Cheng, Hongzhen; Ge, Wei; Ma, Dong; Shi, Yanxi

    2014-01-01

    Soils at depths of 0 cm to 10 cm, 10 cm to 20 cm, and 20 cm to 40 cm from 37 vegetable greenhouses in Shandong Peninsula, East China, were collected, and 16 phthalic acid esters (PAEs) were detected using gas chromatography-mass spectrometry (GC-MS). All 16 PAEs could be detected in soils from vegetable greenhouses. The total of 16 PAEs (Σ16PAEs) ranged from 1.939 mg/kg to 35.442 mg/kg, with an average of 6.748 mg/kg. Among four areas, including Qingdao, Weihai, Weifang, and Yantai, the average and maximum concentrations of Σ16PAEs in soils at depths of 0 cm to 10 cm appeared in Weifang, which has a long history of vegetable production and is famous for extensive greenhouse cultivation. Despite the different concentrations of Σ16PAEs, the PAE compositions were comparable. Among the 16 PAEs, di(2-ethylhexyl) phthalate (DEHP), di-n-octyl phthalate (DnOP), di-n-butyl phthalate (DnBP), and diisobutyl phthalate (DiBP) were the most abundant. Compared with the results on agricultural soils in China, soils that are being used or were used for vegetable greenhouses had higher PAE concentrations. Among PAEs, dimethyl phthalate (DMP), diethyl phthalate (DEP) and DnBP exceeded soil allowable concentrations (in US) in more than 90% of the samples, and DnOP in more than 20%. Shandong Peninsula has the highest PAE contents, which suggests that this area is severely contaminated by PAEs.

  4. Phthalic acid esters in soils from vegetable greenhouses in Shandong Peninsula, East China.

    Directory of Open Access Journals (Sweden)

    Chao Chai

    Full Text Available Soils at depths of 0 cm to 10 cm, 10 cm to 20 cm, and 20 cm to 40 cm from 37 vegetable greenhouses in Shandong Peninsula, East China, were collected, and 16 phthalic acid esters (PAEs were detected using gas chromatography-mass spectrometry (GC-MS. All 16 PAEs could be detected in soils from vegetable greenhouses. The total of 16 PAEs (Σ16PAEs ranged from 1.939 mg/kg to 35.442 mg/kg, with an average of 6.748 mg/kg. Among four areas, including Qingdao, Weihai, Weifang, and Yantai, the average and maximum concentrations of Σ16PAEs in soils at depths of 0 cm to 10 cm appeared in Weifang, which has a long history of vegetable production and is famous for extensive greenhouse cultivation. Despite the different concentrations of Σ16PAEs, the PAE compositions were comparable. Among the 16 PAEs, di(2-ethylhexyl phthalate (DEHP, di-n-octyl phthalate (DnOP, di-n-butyl phthalate (DnBP, and diisobutyl phthalate (DiBP were the most abundant. Compared with the results on agricultural soils in China, soils that are being used or were used for vegetable greenhouses had higher PAE concentrations. Among PAEs, dimethyl phthalate (DMP, diethyl phthalate (DEP and DnBP exceeded soil allowable concentrations (in US in more than 90% of the samples, and DnOP in more than 20%. Shandong Peninsula has the highest PAE contents, which suggests that this area is severely contaminated by PAEs.

  5. Heavy metals in intensive greenhouse vegetable production systems along Yellow Sea of China: Levels, transfer and health risk.

    Science.gov (United States)

    Hu, Wenyou; Huang, Biao; Tian, Kang; Holm, Peter E; Zhang, Yanxia

    2017-01-01

    Recently, greenhouse vegetable production (GVP) has grown rapidly and counts a large proportion of vegetable production in China. In this study, the accumulation, health risk and threshold values of selected heavy metals were evaluated systematically. A total of 120 paired soil and vegetable samples were collected from three typical intensive GVP systems along the Yellow Sea of China. Mean concentrations of Cd, As, Hg, Pb, Cu and Zn in greenhouse soils were 0.21, 7.12, 0.05, 19.81, 24.95 and 94.11 mg kg(-1), respectively. Compared to rootstalk and fruit vegetables, leafy vegetables had relatively high concentrations and transfer factors of heavy metals. The accumulation of heavy metals in soils was affected by soil pH and soil organic matter. The calculated hazard quotients (HQ) of the heavy metals by vegetable consumption decreased in the order of leafy > rootstalk > fruit vegetables with hazard index (HI) values of 0.61, 0.33 and 0.26, respectively. The HI values were all below 1, which indicates that there is a low risk of greenhouse vegetable consumption. Soil threshold values (STVs) of heavy metals in GVP system were established according to the health risk assessment. The relatively lower transfer factors of rootstalk and fruit vegetables and higher STVs suggest that these types of vegetables are more suitable for cultivation in greenhouse soils. This study will provide an useful reference for controlling heavy metals and developing sustainable GVP.

  6. Climate Changes and Countermeasures for Meteorological Disasters during Production Period in Vegetable Greenhouse in Northern Shenyang Province

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective] The aim was to study the climate changes and countermeasures for meteorological disasters during production period in vegetable greenhouse in northern Shenyang. [Method] By dint of local climate data in recent 38 years and using the conventional method of mathematical statistics, the climate changes and countermeasures for meteorological disasters during production period in vegetable greenhouse in northern Shenyang were expounded. [Result] In general, the sunshine condition in new area of Sheny...

  7. [Development of a cultivation technology and selection of leaf vegetable cultures for space greenhouse].

    Science.gov (United States)

    Levinskikh, M A; Signalova, O B; Derendiaeva, T A; Livanskaia, O G; Nefedova, E L; Sychev, V N; Podo'skiĭ, I G

    2001-01-01

    We plan to perform space experiments on development of a technology for cultivation of leaf vegetables that might be a component of future life support systems for space crews. For this purpose, we are going to fly research greenhouses with the crop area from 0.03 up to 0.1 m2 inside the universal docking module of the ISS Russian segment. To prepare for future space experiments, ground investigations were made in order to compare crop capacity of various artificial soils used to grow leaf vegetables in greenhouse Svet. Useful life of root module Svet can be extended with a new technology based on resupply of fibrous substrate with nutrients. The most effective volume of soil per a plant was determined which sustains high productivity of leaf vegetables in Svet. To select leaf vegetables for in-space cultivation, we conducted investigations of productivity, morphometric and biochemical characteristics, and palatability of 18 cultures including alternative greens highly popular in Japan and China which have been earlier tested neither in laboratory nor in space within the closed eco-system projects. We would prioritize mizuna, pak choi, tatsoi, rapina or broccoli raab, and red giant mustard as objects for in-space investigations.

  8. Greenhouse

    Data.gov (United States)

    Federal Laboratory Consortium — PurposeThe greenhouse at ERDC’s Cold Regions Research and Engineering Laboratory (CRREL) is used for germination and root-growth studies to support basic and field...

  9. Sustainability assessment of greenhouse vegetable farming practices from environmental, economic, and socio-institutional perspectives in China.

    Science.gov (United States)

    Yang, Lanqin; Huang, Biao; Mao, Mingcui; Yao, Lipeng; Niedermann, Silvana; Hu, Wenyou; Chen, Yong

    2016-09-01

    To provide growing population with sufficient food, greenhouse vegetable production has expanded rapidly in recent years in China and sustainability of its farming practices is a major concern. Therefore, this study assessed the sustainability of greenhouse vegetable farming practices from environmental, economic, and socio-institutional perspectives in China based on selected indicators. The empirical data were collected through a survey of 91 farm households from six typical greenhouse vegetable production bases and analysis of environmental material samples. The results showed that heavy fertilization in greenhouse vegetable bases of China resulted in an accumulation of N, P, Cd, Cu, Pb, and Zn in soil, nutrient eutrophication in irrigation water, and high Cd in some leaf vegetables cultivated in acidic soil. Economic factors including decreased crop yield in conventional farming bases, limited and site-dependent farmers' income, and lack of complete implementation of subsidy policies contributed a lot to adoption of heavy fertilization by farmers. Also, socio-institutional factors such as lack of unified management of agricultural supplies in the bases operated in cooperative and small family business models and low agricultural extension service efficiency intensified the unreasonable fertilization. The selection of cultivated vegetables was mainly based on farmers' own experience rather than site-dependent soil conditions. Thus, for sustainable development of greenhouse vegetable production systems in China, there are two key aspects. First, it is imperative to reduce environmental pollution and subsequent health risks through integrated nutrient management and the planting strategy of selected low metal accumulation vegetable species especially in acidic soil. Second, a conversion of cooperative and small family business models of greenhouse vegetable bases to enterprises should be extensively advocated in future for the unified agricultural supplies

  10. The Effect of Vegetation Coverage and Greenhouse Area on the Performance of an Earth-to-Air Heat Exchanger in Cooling Mode of Greenhouse

    Directory of Open Access Journals (Sweden)

    M Mohammadi Mogharreb

    2013-02-01

    Full Text Available The underground temperature at a depth of about three to four meters is almost constant during the year. As a result in summer the underground is cooler than the ambient temperature. This potential is considered for greenhouse cooling by using an Earth-to-Air Heat Exchanger (EAHE. In this research the effects of two parameters were investigated: a the area of greenhouse in three levels of 9, 18, 27 m2 and b the percent of vegetation coverage inside the greenhouse in three levels of 0%, 50%, 100% on the performance of EAHE. The experimental design was factorial experiment in a randomized complete block design. The parameters of greenhouse’s inside temperature, thermal energy exchange and coefficient of performance (COP were considered in cooling mode. As one of the remarkable results it was observed that the closed loop utilization of the system was infeasible in cooling mode. This was mainly due to the occurrence of vapor distillation inside the underground pipes and hence the blockages of the air flow. Also the effect of area and the percent of vegetation coverage were significant on the performance of EAHE. The highest average temperature difference between the temperature of testimonial greenhouse and the temperature of greenhouse was observed in treatment of 100% vegetation coverage and 9 m2 floor area which was measured as 9.6°C. The least average temperature difference in the treatment without vegetation coverage and 27 m2 floor area was measured as 5.2 °C. Considering thermal energy exchange in cooling greenhouse with open loop, the best treatment determined for EAHE in this research was the one with 9 m2 floor area and 100% of vegetation coverage.

  11. 1978 Insect Pest Management Guide: Commercial Vegetable Crops and Greenhouse Vegetables. Circular 897.

    Science.gov (United States)

    Illinois Univ., Urbana. Cooperative Extension Service.

    This circular lists suggested uses of insecticides for the control of pests by commercial vegetable farmers. Suggestions are given for selection, dosage and application of insecticides to control pests of cabbage and related crops, beans, cucumbers and other vine crops, tomatoes, potatoes, peppers, corn, and onions. (CS)

  12. Health risks of heavy metals for Population via Consumption of greenhouse vegetables in Hamadan, Iran

    Directory of Open Access Journals (Sweden)

    Mojgan Sohrabi

    2015-10-01

    Full Text Available Background & Aims of the Study: The last 25 years have seen a remarkable increase in public concern about food contamination. Food and water are the main sources of our essential metals.These are also the media through which we are exposed to various toxic metalsAs such, this study aimed to assess the risks arising from the use of greenhouse vegetables, cucumbers, tomatoes and peppers in Hamadan Province. Materials & Methods: Soil and plant samples were digested using wet digestion method (HClO 4 /HNO 3 , 2:1 ratio solution, and the concentrations of total As, Cd, Cu, Pb, and Zn were determined using Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AE. Results: High concentrations of elements As, Cd, Cu, Pb, and Zn were found in vegetables sampled from overused phosphate fertilized soils, which increased the daily intake of metals in food. The Health risk assessment values of all tested vegetables (pepper, cucumber and tomato were below 1 in As and Cd. The health risk index (HRI value above 1 indicated a relative health risk through the ingestion of contaminated vegetables. Conclusions: Heavy metal concentrations should be periodically monitored in vegetables grown in contaminated soils. This study found that long-term fertilizer use led to a growing accumulation of heavy metals (HMs in soils. It would also be beneficial to implement effective remediation technologies to minimize possible impacts on human health. 

  13. Health Risks of Heavy Metals for Population via Consumption of Greenhouse Vegetables in Hamadan, Iran

    Directory of Open Access Journals (Sweden)

    Mojgan Sohrabi

    2015-10-01

    Full Text Available Background & Aims of the Study: The last 25 years have seen a remarkable increase in public concern about food contamination. Food and water are the main sources of our essential metals.These are also the media through which we are exposed to various toxic metalsAs such, this study aimed to assess the risks arising from the use of greenhouse vegetables, cucumbers, tomatoes and peppers in Hamadan Province. Materials & Methods: Soil and plant samples were digested using wet digestion method (HClO4/HNO3, 2:1 ratio solution, and the concentrations of total As, Cd, Cu, Pb, and Zn were determined using Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AE. Results: High concentrations of elements As, Cd, Cu, Pb, and Zn were found in vegetables sampled from overused phosphate fertilized soils, which increased the daily intake of metals in food. The Health risk assessment values of all tested vegetables (pepper, cucumber and tomato were below 1 in As and Cd. The health risk index (HRI value above 1 indicated a relative health risk through the ingestion of contaminated vegetables. Conclusions: Heavy metal concentrations should be periodically monitored in vegetables grown in contaminated soils. This study found that long-term fertilizer use led to a growing accumulation of heavy metals (HMs in soils. It would also be beneficial to implement effective remediation technologies to minimize possible impacts on human health.

  14. Uptake of caesium-137 from peat and compost mould by vegetables in a greenhouse experiment

    Energy Technology Data Exchange (ETDEWEB)

    Malm, J.; Uusi-Rauva, A.; Paakkola, O. (Helsinki Univ. (Finland). Faculty of Agriculture and Forestry); Rantavaara, A. (Finnish Centre for Radiation and Nuclear Safety (STUK), Helsinki (Finland))

    1991-01-01

    A pot experiment was conducted to study the root uptake of {sup 137} Cs by vegetables grown in peat and composite mould in a greenhouse. The {sup 137}Cs in the growing media originated from Chernobyl fallout. The vegetables were cucumber (Cucumis sativus L. var. Farbio VDP SF 76), tomato (Lycopersicon esculentum L. Var. Virosa), parsley (Petroselinum crispum A.W. Hill var. Non plus ultra), radish (Raphanus Sativus L. var. Nondan) and lettuce (Lactuca sativa L. var Atraktion). The effect of adding potassium to the peat was also studied. The transfer factors (activity in plant dry weight/activity in soil dry weight) varied from 0.66 to 1.8 for peat and from 0.060 to 0.19 for compost mould. Addition of potassium did not have any clear effect on the transfer factors. (Author).

  15. Microbial Community and Greenhouse Gas Fluxes from Abandoned Rice Paddies with Different Vegetation.

    Science.gov (United States)

    Kim, Sunghyun; Lee, Seunghoon; McCormick, Melissa; Kim, Jae Geun; Kang, Hojeong

    2016-10-01

    The area of rice paddy fields has declined continuously in East Asian countries due to abandonment of agriculture and concurrent socioeconomic changes. When they are abandoned, rice paddy fields generally transform into wetlands by natural succession. While previous studies have mainly focused on vegetation shifts in abandoned rice paddies, little information is available about how these changes may affect their contribution to wetland functions. As newly abandoned fields proceed through succession, their hydrology and plant communities often change. Moreover, the relationships between these changes, soil microbial characteristics, and emissions of greenhouse gasses are poorly understood. In this study, we examined changes over the course of secondary succession of abandoned rice paddies to wetlands and investigated their ecological functions through changes in greenhouse gas fluxes and microbial characteristics. We collected gas and soil samples in summer and winter from areas dominated by Cyperaceae, Phragmites, and Sphagnum in each site. We found that CO2 emissions in summer were significantly higher than those in winter, but CH4 and N2O emission fluxes were consistently at very low levels and were similar among seasons and locations, due to their low nutrient conditions. These results suggest that microbial activity and abundance increased in summer. Greenhouse gas flux, soil properties, and microbial abundance were not affected by plant species, although the microbial community composition was changed by plant species. This information adds to our basic understanding of the contribution of wetlands that are transformed from abandoned rice paddy systems.

  16. EFFECT OF SOIL SOLARIZATION ON THERMAL REGIME OF PLASTIC GREENHOUSE SOIL

    Directory of Open Access Journals (Sweden)

    Nereu Augusto Streck

    1994-01-01

    Full Text Available SUMMARY Temperature modification in soil of plastic greenhouse caused by solarization was measured during the summer in the Subtropical Central Region of the Rio Grande do Sul State, Brazil. The experiment was carried out in a 10m x 25m greenhouse covered with low density transparent polyethylene (PE. Four 6m x 4m plots were mulched with 100µm thickness PE sheets, from December 12, 1992 to March 7, 1993. Four other plots (same size without the cover were used as control (bare soil. Results indicated that solarization incrased the maximum soil temperature. The average was 11.9, 10.8, 9.8, and 8.6°C over uncovered control soil at 2, 5, 10, and 20cm depth, respectively. The soil temperature reached values of up to 54.4°C at 2cm and 50.2°C at 5cm depth. Temperatures exceeding 45°C and 50°C in solarized soil have also occurred in several days. "Edge effect" in mulched plots was also detected.

  17. Thermo-mechanical response of rigid plastic laminates for greenhouse covering

    Directory of Open Access Journals (Sweden)

    Silvana Fuina

    2016-09-01

    Full Text Available Innovation in the field of protected crops represents an argument of great applied and theoretical research attention due to constantly evolving technologies and automation for higher quality flower and vegetable production and to the corresponding environmental and economic impact. The aim of this paper is to provide an analysis of some thermomechanical properties of rigid polymeric laminates for greenhouses claddings, including innovative tests such as the thermographic ones. Four types of laminates have been analysed: two polycarbonates, a polymethylmethacrylate and a polyethylene terephthalate (PET. The tests gave interesting results on different important properties, such as radiometric properties, limit stresses, strains and ductility. Moreover, a direct comparison of infrared images and force elongation curves gave important information on the relation of the (localised or homogeneous damage evolution, with both an applicative and theoretical implication. Finally, even if to the authors knowledge at present there are no examples of using PET for covering greenhouses, the results of this paper indicates the thermomechanical and radiometric characteristics of this material make it interesting for agricultural applications.

  18. Interactions among vegetation, climate, and herbivory control greenhouse gas fluxes in a subarctic coastal wetland

    Science.gov (United States)

    Kelsey, K. C.; Leffler, A. J.; Beard, K. H.; Schmutz, J. A.; Choi, R. T.; Welker, J. M.

    2016-12-01

    High-latitude ecosystems are experiencing the most rapid climate changes globally, and in many areas these changes are concurrent with shifts in patterns of herbivory. Individually, climate and herbivory are known to influence biosphere-atmosphere greenhouse gas (GHG) exchange; however, the interactive effects of climate and herbivory in driving GHG fluxes have been poorly quantified, especially in coastal systems that support large populations of migratory waterfowl. We investigated the magnitude and the climatic and physical controls of GHG exchange within the Yukon-Kuskokwim Delta in western Alaska across four distinct vegetation communities formed by herbivory and local microtopography. Net CO2 flux was greatest in the ungrazed Carex meadow community (3.97 ± 0.58 [SE] µmol CO2 m-2 s-1), but CH4 flux was greatest in the grazed community (14.00 ± 6.56 nmol CH4 m-2 s-1). The grazed community is also the only vegetation type where CH4 was a larger contributor than CO2 to overall GHG forcing. We found that vegetation community was an important predictor of CO2 and CH4 exchange, demonstrating that variation in regional gas exchange is best explained when the effect of grazing, determined by the difference between grazed and ungrazed communities, is included. Further, we identified an interaction between temperature and vegetation community, indicating that grazed regions could experience the greatest increases in CH4 emissions with warming. These results suggest that future GHG fluxes could be influenced by both climate and by changes in herbivore population dynamics that expand or contract the vegetation community most responsive to future temperature change.

  19. Soil environmental quality in greenhouse vegetable production systems in eastern China: Current status and management strategies.

    Science.gov (United States)

    Hu, Wenyou; Zhang, Yanxia; Huang, Biao; Teng, Ying

    2017-03-01

    Greenhouse vegetable production (GVP) has become an important source of public vegetable consumption and farmers' income in China. However, various pollutants can be accumulated in GVP soils due to the high cropping index, large agricultural input, and closed environment. Ecological toxicity caused by excessive pollutants' accumulation can then lead to serious health risks. This paper was aimed to systematically review the current status of soil environmental quality, analyze their impact factors, and consequently to propose integrated management strategies for GVP systems. Results indicated a decrease in soil pH, soil salinization, and nutrients imbalance in GVP soils. Fungicides, remaining nutrients, antibiotics, heavy metals, and phthalate esters were main pollutants accumulating in GVP soils comparing to surrounding open field soils. Degradation of soil ecological function, accumulation of major pollutants in vegetables, deterioration of neighboring water bodies, and potential human health risks has occurred due to the changes of soil properties and accumulation of pollutants such as heavy metals and fungicides in soils. Four dominant factors were identified leading to the above-mentioned issues including heavy application of agricultural inputs, outmoded planting styles with poor environmental protection awareness, old-fashion regulations, unreasonable standards, and ineffective supervisory management. To guarantee a sustainable GVP development, several strategies were suggested to protect and improve soil environmental quality. Implementation of various strategies not only requires the concerted efforts among different stakeholders, but also the whole lifecycle assessment throughout the GVP processes as well as effective enforcement of policies, laws, and regulations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Preliminary investigation of the transport of small plastic litter along a vegetated riverbank

    Science.gov (United States)

    Liu, Da; Valyrakis, Manousos

    2017-04-01

    Plastics are widely used in consumer products, due to its low cost, low weight and high durability compared to other types of materials. Contamination of marine ecosystems due to plastics (including microplastics) is a challenge that has received a lot of attention due to the significant risks it poses for the environment and human health. Plastics find their way to the ocean from land via the river system. Studying and obtaining a better understanding of the mechanisms contributing to the fate of plastic litter is therefore important in proactively devising methods to reduce their quantity or produce designs to trap plastic pollutants and prevent them from entering the ocean through estuaries. In this context, it is a common observation of hydraulic practitioners and field geomorphologists, that plastic litter can be trapped within riparian vegetation patches along streams or canals, which can be washed away in periods of high flows. To this goal this study aims to use a series of purpose specific physical experiments to examine the mechanisms of dispersion of plastic litter along the water surface of a channel with simulated riparian vegetation. The set of experiments are conducted in a recirculating flume with rigid riverbank and riparian vegetation modeled by a large number of acrylic rods, placed on the top of the riverbank section. Six different sizes of pieces of Styrofoam are used to simulate plastic litter. These are released from different locations upstream and in the vicinity of the riparian vegetation for various configurations (linear, staggered and random) of characteristic solid density. The trajectory of the plastic litter is recorded with a camera offering a top view of the arrangement. From the analysis of this a variety of results are obtained including transport metrics (including transport velocity and time to trapping) and litter-trapping location. The relation between the size of the litter, the vegetation configuration and the traveling

  1. A monitoring system for vegetable greenhouses based on a wireless sensor network.

    Science.gov (United States)

    Li, Xiu-hong; Cheng, Xiao; Yan, Ke; Gong, Peng

    2010-01-01

    A wireless sensor network-based automatic monitoring system is designed for monitoring the life conditions of greenhouse vegetables. The complete system architecture includes a group of sensor nodes, a base station, and an internet data center. For the design of wireless sensor node, the JN5139 micro-processor is adopted as the core component and the Zigbee protocol is used for wireless communication between nodes. With an ARM7 microprocessor and embedded ZKOS operating system, a proprietary gateway node is developed to achieve data influx, screen display, system configuration and GPRS based remote data forwarding. Through a Client/Server mode the management software for remote data center achieves real-time data distribution and time-series analysis. Besides, a GSM-short-message-based interface is developed for sending real-time environmental measurements, and for alarming when a measurement is beyond some pre-defined threshold. The whole system has been tested for over one year and satisfactory results have been observed, which indicate that this system is very useful for greenhouse environment monitoring.

  2. Fungicidal activities of soil humic/fulvic acids as related to their chemical structures in greenhouse vegetable fields with cultivation chronosequence

    Science.gov (United States)

    Wu, Meng; Song, Mengya; Liu, Ming; Jiang, Chunyu; Li, Zhongpei

    2016-01-01

    In the background of rapid expansion of plastic greenhouse vegetable production in China, many environmental risks have emerged in recent years. In this study, the soils with a chronosequence in greenhouse vegetable fields were collected and the soil humic acids (HAs) and fluvic acids (FAs) were extracted and purified. The soil HAs and FAs were found to show inhibition activities against phytopathogenic fungi for the first time. Fourier transform infrared spectroscopy was performed to investigate the chemical structures of HAs and FAs. The variation of relative peak areas indicated the chemical structure of HAs become more complex and stable under continuous cultivation. The PCA analysis showed HAs and FAs could be distinctly separated from each other and cultivation years mainly determined the variation. Mantel test and RDA analysis indicated the active components (aliphatic peaks for HAs and COOH, OH peaks for FAs) had positive correlation with the inhibition rates of HAs and FAs against phytopathogenic fungi. According to our research, the active fungicidal components in soil HAs and FAs decreased along with the extension of cultivation years, which made the soil suffer more risk to phytopathogenic fugi. So we believe continuous cultivation too many years in PGVP systems is inadvisable. PMID:27597259

  3. Fungicidal activities of soil humic/fulvic acids as related to their chemical structures in greenhouse vegetable fields with cultivation chronosequence

    Science.gov (United States)

    Wu, Meng; Song, Mengya; Liu, Ming; Jiang, Chunyu; Li, Zhongpei

    2016-09-01

    In the background of rapid expansion of plastic greenhouse vegetable production in China, many environmental risks have emerged in recent years. In this study, the soils with a chronosequence in greenhouse vegetable fields were collected and the soil humic acids (HAs) and fluvic acids (FAs) were extracted and purified. The soil HAs and FAs were found to show inhibition activities against phytopathogenic fungi for the first time. Fourier transform infrared spectroscopy was performed to investigate the chemical structures of HAs and FAs. The variation of relative peak areas indicated the chemical structure of HAs become more complex and stable under continuous cultivation. The PCA analysis showed HAs and FAs could be distinctly separated from each other and cultivation years mainly determined the variation. Mantel test and RDA analysis indicated the active components (aliphatic peaks for HAs and COOH, OH peaks for FAs) had positive correlation with the inhibition rates of HAs and FAs against phytopathogenic fungi. According to our research, the active fungicidal components in soil HAs and FAs decreased along with the extension of cultivation years, which made the soil suffer more risk to phytopathogenic fugi. So we believe continuous cultivation too many years in PGVP systems is inadvisable.

  4. The power of Dutch greenhouse vegetable horticulture : an analysis of the private sector and its institutional framework

    NARCIS (Netherlands)

    Breukers, A.; Hietbrink, O.; Ruijs, M.N.A.

    2008-01-01

    This report provides an overview of the structure and characteristics of the Dutch greenhouse vegetable sector and its regulatory and institutional frame$work. It also discusses how sector characteristics and the institutional frame$work relate to the performance of the sector in the international m

  5. Contamination, source identification, and risk assessment of polycyclic aromatic hydrocarbons in the soils of vegetable greenhouses in Shandong, China.

    Science.gov (United States)

    Chai, Chao; Cheng, Qiqi; Wu, Juan; Zeng, Lusheng; Chen, Qinghua; Zhu, Xiangwei; Ma, Dong; Ge, Wei

    2017-08-01

    The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) were analyzed in soil (n=196) and vegetable (n=30) collected from greenhouses, and also in the soil (n=27) collected from agriculture fields close to the greenhouses in Shandong Province, China. The total PAH concentration (∑16PAH) ranged from 152.2µg/kg to 1317.7µg/kg, within the moderate range in agricultural soils of China. Three-ring PAHs were the dominant species, with Phe (16.3%), Ace (13.1%), and Fl (10.5%) as the major compounds. The concentrations of low molecular weight (LMW ≤3 rings) PAHs were high in the east and north of Shandong, while the concentrations of high molecular weight (HMW ≥4 rings) PAHs were high in the south and west of the study area. The PAH level in soils in industrial areas (IN) was higher than those in transport areas (TR) and rural areas (RR). No significant difference in concentration of ∑16PAH and composition was observed in soils of vegetable greenhouses and field soils. PAH concentration exhibited a weakly positive correlation with alkaline nitrogen, available phosphorus in soil, but a weakly negative correlation with soil pH. However, no obvious correlation was observed between PAH concentration and organic matter of soil, or ages of vegetable greenhouses. ∑16PAH in vegetables ranged from 89.9µg/kg to 489.4µg/kg, and LMW PAHs in vegetables positively correlated with those in soils. The sources of PAHs were identified and quantitatively assessed through positive matrix factorization. The main source of PAHs in RR was coal combustion, while the source was traffic in TR and IN. Moreover, petroleum source, coke source, biomass combustion, or mixed sources also contributed to PAH pollution. According to Canadian soil quality guidelines, exposure to greenhouse soils in Shandong posed no risk to human health. Copyright © 2017. Published by Elsevier Inc.

  6. Greenhouse gas emissions from the treatment of household plastic containers and packaging: replacement with biomass-based materials.

    OpenAIRE

    Yano, Junya; Hirai, Yasuhiro; Sakai, Shin-ichi; Tsubota, Jun

    2014-01-01

    The purpose of this study was to quantify the life-cycle greenhouse gas (GHG) emissions reduction that could be achieved by replacement of fossil-derived materials with biodegradable, biomass-based materials for household plastic containers and packaging, considering a variety of their treatment options. The biomass-based materials were 100% polylactide or a combination of polybutylene succinate adipate and polylactide. A scenario analysis was conducted considering alternative recycling metho...

  7. Carbon dioxide enrichment of greenhouse vegetable through the use of diesel exhaust gas. [Cucumis sativus; Lactuca sp

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, M.H.; Hodges, C.N.

    1970-01-01

    Two cucumber and eight lettuce varieties were grown in two air-supported, closed-environment plastic greenhouses, one with approximately ambient CO2 levels, and the other enriched with 1400 ppm CO2. Diesel exhaust gas was the source of the carbon dioxide. Once the exhaust gases were scrubbed through seawater and put through an activated charcoal filter, essentially no other gases entered the greenhouse along with the CO2. Cucumbers grown in the enriched environment came into production one week earlier, and one variety produced significantly higher yields, than those grown at near ambient levels of CO2. Lettuce grown in the CO2 enriched greenhouse weighed, at market maturity, nearly twice as much as lettuce grown at ambient levels.

  8. [Treatment effect of biological filtration and vegetable floating-bed combined system on greenhouse turtle breeding wastewater].

    Science.gov (United States)

    Chen, Chong-Jun; Zhang, Rui; Xiang, Kun; Wu, Wei-Xiang

    2014-08-01

    Unorganized discharge of greenhouse turtle breeding wastewater has brought several negative influences on the ecological environment in the rural area of Yangtze River Delta. Biological filtration and vegetable floating-bed combined system is a potential ecological method for greenhouse turtle breeding wastewater treatment. In order to explore the feasibility of this system and evaluate the contribution of vegetable uptake of nitrogen (N) and phosphorus (P) in treating greenhouse turtle breeding wastewater, three types of vegetables, including Ipomoea aquatica, lettuce and celery were selected in this study. Results showed the combined system had a high capacity in simultaneous removal of organic matter, N and P. The removal efficiencies of COD, NH4(+)-N, TN and TP from the wastewater reached up to 93.2%-95.6%, 97.2%-99.6%, 73.9%-93.1% and 74.9%-90.0%, respectively. System with I. aquatica had the highest efficiencies in N and P removal, followed by lettuce and celery. However, plant uptake was not the primary pathway for TN arid TP removal in the combined system. The vegetable uptake of N and P accounted for only 9.1%-25.0% of TN and TP removal from the wastewater while the effect of microorganisms would be dominant for N and P removal. In addition, the highest amounts of N and P uptake in I. aquatica were closely related with the biomass of plant. Results from the study indicated that the biological filtration and vegetable floating-bed combined system was an effective approach to treating greenhouse turtle breeding wastewater in China.

  9. Reducing greenhouse gas emissions by recycling plastics and textiles into products

    OpenAIRE

    Korhonen, Marja-Riitta; Dahlbo, Helena

    2007-01-01

    Waste management generates greenhouse gas emissions. New waste management concepts for reducing these emissions are continuously being developed. In this study the potential of material recovery to reduce greenhouse gas emissions was assessed. The study was divided into two phases. In the first phase the material recovery concepts used in Finland were identified and approximate greenhouse gas emission savings calculations were conducted for some of the concepts. In the second phase two promis...

  10. [Effects of fertilization on the P accumulation and leaching in vegetable greenhouse soil].

    Science.gov (United States)

    Zhao, Ya-jie; Zhao, Mu-qiu; Lu, Cai-yan; Shi, Yi; Chen, Xin

    2015-02-01

    A packed soil column experiment was conducted to investigate the effect of different fertilization practices on phosphorus (P) accumulation and leaching potential in a vegetable greenhouse soil with different fertility levels. The results showed that the leaching loss of total P in the leachates elevated with the increment of leaching time while the accumulative leaching loss of total P was relatively low, indicating P was mainly accumulated in the soil instead of in the leachate. At the end of the leaching experiment, soil fertility and fertilization treatment affected the content of total phosphorus and Olsen-P significantly. Compared with the low-level-fertility soil, the contents of total P and Olsen-P increased by 14.3% and 12.2% in the medium-level-fertility soil, 33.3% and 37.7% in the high-level-fertility soil. Total P in the combined application of poultry manure and chemical fertilizer (M+NPK) was elevated by 5.7% and 4.3%, compared with the NPK and M treatment. Compared with NPK treatment, Olsen-P in M and M + NPK treatments augmented by 13.0% and 3.1%, respectively. Soil total P and Olsen-P mainly accumulated in the 0-10 cm and 10-20 cm soil layers, and much less in the 20-40 cm soil layer.

  11. Changes in Arctic vegetation amplify high-latitude warming through the greenhouse effect.

    Science.gov (United States)

    Swann, Abigail L; Fung, Inez Y; Levis, Samuel; Bonan, Gordon B; Doney, Scott C

    2010-01-26

    Arctic climate is projected to change dramatically in the next 100 years and increases in temperature will likely lead to changes in the distribution and makeup of the Arctic biosphere. A largely deciduous ecosystem has been suggested as a possible landscape for future Arctic vegetation and is seen in paleo-records of warm times in the past. Here we use a global climate model with an interactive terrestrial biosphere to investigate the effects of adding deciduous trees on bare ground at high northern latitudes. We find that the top-of-atmosphere radiative imbalance from enhanced transpiration (associated with the expanded forest cover) is up to 1.5 times larger than the forcing due to albedo change from the forest. Furthermore, the greenhouse warming by additional water vapor melts sea-ice and triggers a positive feedback through changes in ocean albedo and evaporation. Land surface albedo change is considered to be the dominant mechanism by which trees directly modify climate at high-latitudes, but our findings suggest an additional mechanism through transpiration of water vapor and feedbacks from the ocean and sea-ice.

  12. [Concentration and speciation of arsenic in greenhouse vegetable soil in Shouguang County of Shandong Province].

    Science.gov (United States)

    Hu, Liu-Jie; Zeng, Xi-Bai; Bai, Ling-Yu; Li, Lian-Fang

    2011-01-01

    A sampling survey was conducted in the typical areas in Shouguang County of Shandong Province to study the characteristics of arsenic (As) concentration and speciation in greenhouse vegetable soil. The total As concentration in the surface (0-20 cm) and subsurface (20-40 cm) soil was averagely 8.27 and 7.93 mg x kg(-1), being 19% and 23% higher than that of the control (open field soil), and the soluble As (AE-As) concentration was 0.13 and 0.06 mg x kg(-1), 63% and 200% higher than that of the control, respectively. The ratio of residual As (O-As) to total arsenic reached more than 63.0%, and the concentrations of different As speciation decreased in the order of O-As > iron-bound As (Fe-As) > calcium bound As (Ca-As) > aluminum bound As (AlAs) > AE-As. With the increasing planting years, the AE-As concentration enhanced significantly, and the Al-As concentration also increased to some degree. After 15 years planting, the AE-As concentration in surface and subsurface soil increased by 75.0% and 150.0%, and Al-As concentration increased by 51.6% and 190.4%, respectively, while the concentrations of Fe-As and Ca-As all decreased to some degree.

  13. Occurrence of antibiotics in soils and manures from greenhouse vegetable production bases of Beijing, China and an associated risk assessment.

    Science.gov (United States)

    Li, Cheng; Chen, Jiayi; Wang, Jihua; Ma, Zhihong; Han, Ping; Luan, Yunxia; Lu, Anxiang

    2015-07-15

    The occurrence of 15 antibiotics in soil and manure samples from 11 large-scale greenhouse vegetable production (GVP) bases in Beijing, China was investigated. Results showed that the greenhouse soils were ubiquitously contaminated with antibiotics, and that antibiotic concentrations were significantly higher in greenhouses than in open field soils. The mean concentrations of four antibiotic classes decreased in the following order: tetracyclines (102μg/kg)>quinolones (86μg/kg)>sulfonamides (1.1μg/kg)>macrolides (0.62μg/kg). This investigation also indicated that fertilization with manure and especially animal feces might be the primary source of antibiotics. A risk assessment based on the calculated risk quotients (RQs) demonstrated that oxytetracycline, chlortetracycline, norfloxacin, ciprofloxacin and enrofloxacin could pose a high risk to soil organisms. These results suggested that the ecological effects of antibiotic contamination in GVP bases and their potential adverse risks on human health need to be given special attention.

  14. Greenhouse gas emissions from the treatment of household plastic containers and packaging: replacement with biomass-based materials.

    Science.gov (United States)

    Yano, Junya; Hirai, Yasuhiro; Sakai, Shin-ichi; Tsubota, Jun

    2014-04-01

    The purpose of this study was to quantify the life-cycle greenhouse gas (GHG) emissions reduction that could be achieved by replacement of fossil-derived materials with biodegradable, biomass-based materials for household plastic containers and packaging, considering a variety of their treatment options. The biomass-based materials were 100% polylactide or a combination of polybutylene succinate adipate and polylactide. A scenario analysis was conducted considering alternative recycling methods. Five scenarios were considered: two for existing fossil-derived materials (the current approach in Japan) and the three for biomass-based materials. Production and waste disposal of 1 m(3) of plastic containers and packaging from households was defined as the functional unit. The results showed that replacement of fossil-derived materials with biomass-based materials could reduce life-cycle GHG emissions by 14-20%. Source separation and recycling should be promoted. When the separate collection ratio reached 100%, replacement with biomass-based materials could potentially reduce GHG emissions by 31.9%. Food containers are a priority for replacement, because they alone could reduce GHG emissions by 10%. A recycling system for biomass-based plastics must be carefully designed, considering aspects such as the transition period from fossil-derived plastics to biomass-based plastics.

  15. Yield Traits and Water and Nitrogen Use Efficiencies of Bell Pepper Grown in Plastic-Greenhouse

    Directory of Open Access Journals (Sweden)

    Anna Rita Rivelli

    2009-09-01

    Full Text Available We report the results of a two-year study assessing the effects of nitrogen fertilization and irrigation regimes on yield traits and on water and nitrogen use efficiency of greenhouse-grown bell pepper (Capsicum annuum L.. The trials involved the combination of four N doses (0, 100, 200, 300 kg ha-1 with two irrigation regimes (100% restitution of ETc; repeated cycles of water stress starting from fruit set. In the second year, the crop was transplanted one month earlier than in the first year and was mulched with plastic sheeting. The highest yield in both years was obtained by associating 100% restitution of ETc and the N dose of 200 kg ha-1. The marketable yields were 37 and 72 t ha-1 in 1998 and 1999, respectively. Doubling of the yield in the second year was probably due to the earlier transplantation and mulching, confirming the numerous benefits of the latter technique. The water deficit imposed during the late flowering-early fruit set phase had negative effects on the crop, with declines of the marketable yield of up to 44% due to the reduced number and weight of the fruit and the increased waste, mainly peppers with blossom-end rot, cracking, sun-burn and malformations. The peppers grown under water stress were richer in dry matter and soluble solids. The yield declines due to water deficit varied in relation to the N dose, as confirmed by the numerous interactions recorded between irrigation regime and nitrogen level.Without nitrogen fertilization, the quantity and quality of the fruits remained unchanged, while the maximum dose (300 kg ha-1 enhanced the negative effects of the water deficit on the number (-52% and weight (-161% of marketable peppers. Moreover, the waste peppers reached 31% of the total production (by weight, with over 21% affected by blossom-end rot. Water stress led to a drastic reduction of the total above-ground dry biomass (40% and a significant decrease of nitrogen absorption by the plant (54% with preferential

  16. Epoxidized Vegetable Oils Plasticized Poly(lactic acid Biocomposites: Mechanical, Thermal and Morphology Properties

    Directory of Open Access Journals (Sweden)

    Buong Woei Chieng

    2014-10-01

    Full Text Available Plasticized poly(lactic acid PLA with epoxidized vegetable oils (EVO were prepared using a melt blending method to improve the ductility of PLA. The plasticization of the PLA with EVO lowers the Tg as well as cold-crystallization temperature. The tensile properties demonstrated that the addition of EVO to PLA led to an increase of elongation at break, but a decrease of tensile modulus. Plasticized PLA showed improvement in the elongation at break by 2058% and 4060% with the addition of 5 wt % epoxidized palm oil (EPO and mixture of epoxidized palm oil and soybean oil (EPSO, respectively. An increase in the tensile strength was also observed in the plasticized PLA with 1 wt % EPO and EPSO. The use of EVO increases the mobility of the polymeric chains, thereby improving the flexibility and plastic deformation of PLA. The SEM micrograph of the plasticized PLA showed good compatible morphologies without voids resulting from good interfacial adhesion between PLA and EVO. Based on the results of this study, EVO may be used as an environmentally friendly plasticizer that can improve the overall properties of PLA.

  17. Assessing the risks of trace elements in environmental materials under selected greenhouse vegetable production systems of China

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yong [Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Huang, Biao, E-mail: bhuang@issas.ac.cn [Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Hu, Wenyou [Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Weindorf, David C.; Liu, Xiaoxiao [Department of Plant and Soil Science, Texas Tech University, Lubbock, TX (United States); Niedermann, Silvana [Department of Environmental Systems Science, Institute of Agricultural Science, ETH Zurich, 8092 Zurich (Switzerland)

    2014-02-01

    The risk assessment of trace elements of different environmental media in conventional and organic greenhouse vegetable production systems (CGVPS and OGVPS) can reveal the influence of different farming philosophy on the trace element accumulations and their effects on human health. These provide important basic data for the environmental protection and human health. This paper presents trace element accumulation characteristics of different land uses; reveals the difference of soil trace element accumulation both with and without consideration of background levels; compares the trace element uptake by main vegetables; and assesses the trace element risks of soils, vegetables, waters and agricultural inputs, using two selected greenhouse vegetable systems in Nanjing, China as examples. Results showed that greenhouse vegetable fields contained significant accumulations of Zn in CGVPS relative to rice–wheat rotation fields, open vegetable fields, and geochemical background levels, and this was the case for organic matter in OGVPS. The comparative analysis of the soil medium in two systems with consideration of geochemical background levels and evaluation of the geo-accumulation pollution index achieved a more reasonable comparison and accurate assessment relative to the direct comparison analysis and the evaluation of the Nemerow pollution index, respectively. According to the Chinese food safety standards and the value of the target hazard quotient or hazard index, trace element contents of vegetables were safe for local residents in both systems. However, the spatial distribution of the estimated hazard index for producers still presented certain specific hotspots which may cause potential risk for human health in CGVPS. The water was mainly influenced by nitrogen, especially for CGVPS, while the potential risk of Cd and Cu pollution came from sediments in OGVPS. The main inputs for trace elements were fertilizers which were relatively safe based on relevant

  18. Coastal vegetation invasion increases greenhouse gas emission from wetland soils but also increases soil carbon accumulation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yaping [Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, College of the Environment and Ecology, Xiamen University, Xiamen 361102, Fujian (China); Chen, Guangcheng [Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, Fujian (China); Ye, Yong, E-mail: yeyong.xmu@gmail.com [Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, College of the Environment and Ecology, Xiamen University, Xiamen 361102, Fujian (China)

    2015-09-01

    Soil properties and soil–atmosphere fluxes of CO{sub 2}, CH{sub 4} and N{sub 2}O from four coastal wetlands were studied throughout the year, namely, native Kandelia obovata mangrove forest vs. exotic Sonneratia apetala mangrove forest, and native Cyperus malaccensis salt marsh vs. exotic Spartina alterniflora salt marsh. Soils of the four wetlands were all net sources of greenhouse gases while Sonneratia forest contributed the most with a total soil–atmosphere CO{sub 2}-equivalent flux of 137.27 mg CO{sub 2} m{sup −2} h{sup −1}, which is 69.23%, 99.75% and 44.56% higher than that of Kandelia, Cyperus and Spartina, respectively. The high underground biomass and distinctive root structure of Sonneratia might be responsible for its high greenhouse gas emission from the soil. Soils in Spartina marsh emitted the second largest amount of total greenhouse gases but it ranked first in emitting trace greenhouse gases. Annual average CH{sub 4} and N{sub 2}O fluxes from Spartina soil were 13.77 and 1.14 μmol m{sup −2} h{sup −1}, respectively, which are 2.08 and 1.46 times that of Kandelia, 1.03 and 1.15 times of Sonneratia, and 1.74 and 1.02 times of Cyperus, respectively. Spartina has longer growing season and higher productivity than native marshes which might increase greenhouse gas emission in cold seasons. Exotic wetland soils had higher carbon stock as compared to their respective native counterparts but their carbon stocks were offset by a larger proportion because of their higher greenhouse gas emissions. Annual total soil–atmosphere fluxes of greenhouse gases reduced soil carbon burial benefits by 8.1%, 9.5%, 6.4% and 7.2% for Kandelia, Sonneratia, Cyperus and Spartina, respectively, which narrowed down the gaps in net soil carbon stock between native and exotic wetlands. The results indicated that the invasion of exotic wetland plants might convert local coastal soils into a considerable atmospheric source of greenhouse gases although they at the

  19. 倍赢番茄大棚越冬栽培技术%Overwintering Technique for Tomato "Beiying" in Plastic Greenhouse

    Institute of Scientific and Technical Information of China (English)

    汪秀云

    2011-01-01

    The cultivation experiments of tomato cultivar "Beiying" were carried out in plastic greenhouse.This tomato cultivar displayed traits of high yield,good quality,strong disease resistance and broad adaptability.This paper mainly introduced the overwintering techniques for tomato "Beiying" in plastic greenhouse.%通过对倍赢番茄进行大棚栽培,该品种表现丰产、优质、抗病性强、适应性好。该文主要介绍倍赢番茄的大棚越冬栽培技术。

  20. The impact of greenhouse vegetable farming duration and soil types on phytoavailability of heavy metals and their health risk in eastern China.

    Science.gov (United States)

    Yang, Lanqin; Huang, Biao; Hu, Wenyou; Chen, Yong; Mao, Mingcui; Yao, Lipeng

    2014-05-01

    Heavy metal contamination in vegetables from greenhouse vegetable production (GVP) in China requires major attention. For GVP sustainability at a large regional level, 441 surface GVP soil and 132 corresponding greenhouse vegetable samples were collected from six typical GVP bases in eastern China to systematically evaluate the impact of GVP duration and soil types (Anthrosols and Cambosols) on phytoavailability of four major metals, Cd, Cu, Zn, and Pb, and their health risk. The results revealed high Cd accumulation in leaf vegetables grown in Anthrosols, which might pose potential health risk. Regardless of soil types in the study region, greenhouse farming lowered soil pH and enhanced metal availability with rising GVP duration, which might exacerbate Cd phytoavailability and vegetable Cd contamination as well as potential health risk. Also, increased GVP soil organic matter contents over time, found in some locations, affected crop-depending Cu and Zn uptakes. Furthermore, due to GVP, the annual decrease rate of soil pH and increase rates of soil available metal concentrations were generally much greater in Anthrosols than those in Cambosols, which contributed a lot to high Cd uptake by leaf vegetables grown in Anthrosols and their potential health risk. From sustainable GVP perspective, fertilization strategy with reduced frequency and rate is especially important and effective for abating soil and vegetable contamination by heavy metals under greenhouse farming.

  1. Predicting the energy consumption of heated plastic greenhouses in south-eastern Spain

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, J. C.; Baile, A.; Bonachela, S.; Gonzalez-Real, M. M.; Perez-Parra, J.

    2006-07-01

    Measurements of heat consumption in a parral type greenhouse, equipped with an air-heating system, were carried out in south-eastern Spain (Almeria) during the 1998/99 winter. From the daily values of heat consumption (Qd, MJ m-2 d-1) recorded in five identical greenhouses heated to different night temperature set-points (Tc), and data of minimum outside air temperature (Te,min), relationships between Qd and the temperature difference (Tmin = Tc . Te,min) were established. Linear regressions between Qd and delta Tmin gave satisfactory fits (R2 ranging from 0.75 to 0.83), considering that Te,min was the only input data for the model. When all data were pooled, the correlation was curvilinear, the best fit to a 2nd order polynomial being Qd = 0.049 deltaTmin 2 . 0.001 Tmin + 1.107 (R2 = 0.89). Validation of this model was performed using data obtained during other years, giving a fair agreement at the daily (R2 0.86), 10-day (R2 = 0.95) and yearly (R2 = 0.99) time scales. This simple model could be of interest to growers for decision-making related to the choice of set-point temperature and crop planning in heated greenhouses. (Author)

  2. Water level, vegetation composition and plant productivity explain greenhouse gas fluxes in temperate cutover fens after inundation

    Directory of Open Access Journals (Sweden)

    M. Minke

    2015-10-01

    Full Text Available Rewetting of temperate continental cutover peatlands generally implies the creation of flooded areas, which are – dependent on water depth – colonized by helophytes such as Eriophorum angustifolium, Carex spp., Typha latifolia or Phragmites australis. Reeds of Typha and Phragmites are reported to be large sources of methane, but data on net CO2 uptake are contradictory for Typha and rare for Phragmites. This paper describes the effect of vegetation, water level and nutrient conditions on greenhouse gas (GHG emissions for representative vegetation types along water level gradients at two rewetted cutover fens (mesotrophic and eutrophic in Belarus. Greenhouse emissions were measured with manual chambers in weekly to few – weekly intervals over a two years period and interpolated by modelling. All sites had negligible nitrous oxide exchange rates. Most sites were carbon sinks and small GHG sources. Methane emissions were generally associated with net ecosystem CO2 uptake. Small sedges were minor methane emitters and net CO2 sinks, while Phragmites australis sites released large amounts of methane and sequestered very much CO2. Variability of both fluxes increased with site productivity. Floating mats composed of Carex tussocks and Typha latifolia were a source for both methane and CO2. We conclude that shallow, stable flooding is a better measure to arrive at low GHG emissions than deep flooding, and that the risk of high GHG emissions consequent on rewetting is larger for eutrophic than for mesotrophic peatlands.

  3. Short-Term Responses of Nitrogen Mineralization and Microbial Community to Moisture Regimes in Greenhouse Vegetable Soils

    Institute of Scientific and Technical Information of China (English)

    CHEN Qiu-Hui; FENG Ying; ZHANG Yan-Ping; ZHANG Qi-Chun; I.H.SHAMSI; ZHANG Yong-Song; LIN Xian-Yong

    2012-01-01

    Soil drying and wetting impose significant influences on soil nitrogen (N) dynamics and microbial communities.However,effects of drying-wetting cycles,while common in vegetable soils,especially under greenhouse conditions,have not been well studied.In this study,two greenhouse vegetable soils,which were collected from Xinji (X J) and Hangzhou (HZ),China,were maintained at 30% and 75% water-holding capacity (WHC),or five cycles of 75% WHC followed by a 7-day dry-down to 30% WHC (DW).Soil inorganic N content increased during incubation.Net N mineralization (Nmin),microbial activity,and microbial biomass were significantly higher in the DW treatment than in the 30% and 75% WHC treatments.The higher water content (75% WHC) treatment had higher Nmin,microbial activity,and microbial biomass than the lower water content treatment (30% WHC).Multivariate analyses of community-level physiological profile (CLPP) and phospholipid fatty acid (PLFA) data indicated that soil moisture regime had a significant effect on soil microbial community substrate utilization pattern and microbial community composition.The significant positive correlation between Nmin and microbial substrate utilization or PLFAs suggested that soil N mineralization had a close relationship with microbial community.

  4. Effects of CO2 concentration on photosynthesis, transpiration and production of greenhouse fruit vegetable crops.

    NARCIS (Netherlands)

    Nederhoff, E.M.

    1994-01-01

    The effect of the C0 2 concentration of the greenhouse air (C) in the range 200 to 1100 μmol mol -1was investigated in tomato ( Lycopersicon esculentum Mill.), cucumber ( Cucumis sativus L.), sweet pepper ( Capsicum annuum L.) and eggplant ( Solanum melongena L.), grown in gree

  5. Efficacy of microbial amendments on vegetables in greenhouse and field trials

    Science.gov (United States)

    Soil amendments, with and without microbes, may affect plant development. Eight-week-old, organically grown, seedlings of a bell, cv. Jupiter, and a non-pungent jalapeño, cv. Pace 105, pepper (both Capsicum annuum L.) were transplanted into pots in a greenhouse using an organic potting medium. One...

  6. Water level, vegetation composition, and plant productivity explain greenhouse gas fluxes in temperate cutover fens after inundation

    Science.gov (United States)

    Minke, Merten; Augustin, Jürgen; Burlo, Andrei; Yarmashuk, Tatsiana; Chuvashova, Hanna; Thiele, Annett; Freibauer, Annette; Tikhonov, Vitalij; Hoffmann, Mathias

    2016-07-01

    Peat extraction leaves a land surface with a strong relief of deep cutover areas and higher ridges. Rewetting inundates the deep parts, while less deeply extracted zones remain at or above the water level. In temperate fens the flooded areas are colonized by helophytes such as Eriophorum angustifolium, Carex spp., Typha latifolia or Phragmites australis dependent on water depth. Reeds of Typha and Phragmites are reported as large sources of methane, but data on net CO2 uptake are contradictory for Typha and rare for Phragmites. Here, we analyze the effect of vegetation, water level and nutrient conditions on greenhouse gas (GHG) emissions for representative vegetation types along water level gradients at two rewetted cutover fens (mesotrophic and eutrophic) in Belarus. Greenhouse gas emissions were measured campaign-wise with manual chambers every 2 to 4 weeks for 2 years and interpolated by modelling. All sites had negligible nitrous oxide exchange rates. Most sites were carbon sinks and small GHG sources. Methane emissions generally increased with net ecosystem CO2 uptake. Mesotrophic small sedge reeds with water table around the land surface were small GHG sources in the range of 2.3 to 4.2 t CO2 eq. ha-1 yr-1. Eutrophic tall sedge - Typha latifolia reeds on newly formed floating mats were substantial net GHG emitters in the range of 25.1 to 39.1 t CO2 eq. ha-1 yr. They represent transient vegetation stages. Phragmites reeds ranged between -1.7 to 4.2 t CO2 eq. ha-1 yr-1 with an overall mean GHG emission of 1.3 t CO2 eq. ha-1 yr-1. The annual CO2 balance was best explained by vegetation biomass, which includes the role of vegetation composition and species. Methane emissions were obviously driven by biological activity of vegetation and soil organisms. Shallow flooding of cutover temperate fens is a suitable measure to arrive at low GHG emissions. Phragmites australis establishment should be promoted in deeper flooded areas and will lead to moderate, but

  7. Elastic and plastic soil deformation and its influence on emission of greenhouse gases

    Science.gov (United States)

    Haas, Christoph; Holthusen, Dörthe; Mordhorst, Anneka; Lipiec, Jerzy; Horn, Rainer

    2016-04-01

    Soil management alters physical, chemical and biological soil properties. Stress application affects microbiological activity and habitats for microorganisms in the root zone and causes soil degradation. We hypothesized that stress application results in altered greenhouse gas emissions if soil strength is exceeded. In the experiments, soil management dependent greenhouse gas emissions of intact soil cores (no, reduced, conventional tillages) were determined using two experimental setups; CO2 emissions were determined with: a dynamic measurement system, and a static chamber method before and after a vertical soil stress had been applied. For the latter CH4 and N2O emissions were analyzed additionally. Stress dependent effects can be summed as follows: In the elastic deformation range microbiological activity increased in conventional tillage soil and decreased in reduced tillage and no tillage. Beyond the precompression stress a release of formerly protected soil organic carbon and an almost total loss of CH4 oxidizability occurred. Only swelling and shrinkage of no tillage and reduced tillage regenerated their microhabitat function. Thus, the direct link between soil strength and microbial activity can be applied as a marker for soil rigidity and the transition to new disequilibria concerning microbial activity and composition.

  8. Greenhouse gas emission response to global change may be limited by vegetation community shifts

    Science.gov (United States)

    Coastal marshes experience a confluence of global changes including climate change, sea level rise, exotic species invasion, and eutrophication. These changes are likely to exert new abiotic stressors and affect interspecific interactions that influence vegetation community stru...

  9. Gardening with Greenhouses

    Science.gov (United States)

    Keeler, Rusty

    2010-01-01

    Greenhouses come in all shapes, sizes, and price ranges: from simple hand-built plastic-covered frames to dazzling geodesic domes. Some child care centers install greenhouses as a part of their outdoor garden space. Other centers have incorporated a greenhouse into the building itself. Greenhouses provide a great opportunity for children to grow…

  10. Responses of Agronomic Benefit and Soil Quality to Better Management of Nitrogen Fertilizer Application in Greenhouse Vegetable Land

    Institute of Scientific and Technical Information of China (English)

    JIANG Hui-Min; ZHANG Jian-Feng; SONG Xiao-Zong; LIU Zhao-Hui; JIANG Li-Hua; YANG Jun-Cheng

    2012-01-01

    As a result of intensive greenhouse vegetable production in northern China,the potential risk of nitrogen (N) fertilizer over-applied is increasingly apparent and is threatening ecosystem and the sustainability of food production.An experiment was carried out in Shouguang,Shangdong Province,China to evaluate agronomic benefit and soil quality under different N applications,including the conventional chemical N rate (1 000 kg N ha-1 season-1,N1),70% of N1 (N2),70% of N1 + maize straw (N3),50% of N1 + maize straw + drip irrigation (N4),and 0% of N1 (N0),during two successive growing seasons of autumn-winter (AW) and winter-spring (WS).The maximum yields for N4 were 1.1 and 1.0 times greater than those for N1 in the AW and WS seasons,respectively.N agronomic efficiency (AEN) and apparent N recovery efficiency (REN) were greatest with the N4.A significant relationship was found between soil NO3--N content and electrical conductivity (EC) (R2=0.61 in the AW season and R2 =0.29 in the WS season) Reducing N fertilizer decreased soil NO3--N accumulation (20.9%-37.8% reduction in the AW season and 11.7% 20.1% reduction in the WS season) relative to the accumulation observed for N1 within the 0-100 cm soil layer.Soil urease and invertase activities were not significantly different among N treatments.The N4 treatment would be practical for reducing excess N input and maintaining the sustainability of greenhouse-based intensive vegetable systems in Shouguang.

  11. Study on the idity fuzzy neural network controller based on improved genetic algorithm of intelligent temperature control system in vegetable greenhouse

    Science.gov (United States)

    Zhang, Su; Yuan, Hongbo; Zhou, Yuhong; Wang, Nan

    2009-07-01

    In order to create the environment that the suitable crop grows, direct against the characteristic of the system of the greenhouse. The aim of the research was to study the intelligent temperature control system in vegetable greenhouse. Based on computer automatic control ,a kind of intelligent temperature control system in vegetable greenhouse was designed. The design thought of systematic hardwares such as temperature collection system, temperature display, control system, heater control circuit in the heater were expounded in detail The control algorithm of the system was improved and system simulation was made by using MATLAB finally. The control algorithm of the system was improved by a new fuzzy neural network controller. The stimulation curve showed that the system had better controlling and tracking performances ,higher accuracy of controlling the temperature. And this system and host epigyny computer could constitute the secondary computer control system which was favorable for realizing the centralized management of the production.

  12. Accumulation, sources and health risks of trace metals in elevated geochemical background soils used for greenhouse vegetable production in southwestern China.

    Science.gov (United States)

    Zhang, Haidong; Huang, Biao; Dong, Linlin; Hu, Wenyou; Akhtar, Mohammad Saleem; Qu, Mingkai

    2017-03-01

    Greenhouse vegetable cultivation with substantive manure and fertilizer input on soils with an elevated geochemical background can accumulate trace metals in soils and plants leading to human health risks. Studies on trace metal accumulation over a land use shift duration in an elevated geochemical background scenario are lacking. Accumulation characteristics of seven trace metals in greenhouse soil and edible plants were evaluated along with an assessment of the health risk to the consumers. A total of 118 greenhouse surface soils (0-20cm) and 30 vegetables were collected from Kunming City, Yunnan Province, southwestern China, and analyzed for total Cd, Pb, Cu, Zn, As, Hg, and Cr content by ICP-MS and AFS. The trace metals were ordered Cu>Cd>Hg>Zn>Pb>As>Cr in greenhouse soils accumulation level, and the geo-accumulation index suggested the soil more severely polluted with Cd, Cu, Hg and Zn. The greenhouse and open-field soils had significant difference in Cd, Cr and Zn. The duration of shift from paddy to greenhouse land-use significantly influenced trace metal accumulation with a dramatic change during five to ten year greenhouse land-use, and continuous increase of Cd and Hg. A spatial pattern from north to south for Cd and Hg and a zonal pattern for Cu and Zn were found. An anthropogenic source primarily caused trace metal accumulation, where the principal component analysis/multiple linear regression indicated a contribution 61.2%. While the assessment showed no potential risk for children and adults, the hazard health risks index was greater than one for adolescents. The extended duration of land use as greenhouses caused the trace metal accumulation, rotation in land use should be promoted to reduce the health risks. Copyright © 2016. Published by Elsevier Inc.

  13. Variation in spread of Heterobasidion annosum in clones of Picea abies grown at different vegetation phases under greenhouse conditions

    Energy Technology Data Exchange (ETDEWEB)

    Svedjemark, G.; Stenlid, J. [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Forest Mycology and Pathology

    1996-06-01

    Forty-nine Picea abies (L.) Karst clones were inoculated under greenhouse conditions with a Heterobasidion annosum (Fr.) Bref. isolate of the S intersterility group. The cuttings were inoculated at the following vegetation stages; bud-flushing stage, vegetative stage and after bud-set. Fungal growth in sapwood and leison length in the inner bark were measured after 34 days. The susceptibility of the various clones to H. annosum was strongly correlated among the three vegetation stages, both in terms of mean growth and mean growth ranking. Partitioning of variance components showed that variation in growth was explained by physiological stages and clone to 4% and 24%, respectively, and for interaction between clone and physiological stage to 9%. Corresponding values for leison length in the inner bark were 3%, 14% and 5%, respectively. Fungal growth in wood and leison length in the inner bark were strongly correlated (r{sup 2} ranging between 0.23 and 0.36). When cuttings were inoculated during bud-flushing, leison length and fungal growth in wood were both strongly correlated with bud-flushing index of the cuttings (r{sup 2} = 0.03 and 0.04 respectively) but that was not the case for the other stages. The number of active fine-roots and the degree of wilting of the cuttings were negatively correlated with leison length and fungal growth (r{sup 2} ranging between 0.01 and 0.13). Height and diameter varied greatly between the clones and both were negatively correlated with fungal extension (r{sup 2} ranging between 0.01 and 0.09). 33 refs, 2 figs, 3 tabs

  14. Agriculture: Nurseries and Greenhouses

    Science.gov (United States)

    Nurseries and Greenhouses. Information about environmental requirements specifically relating to the production of many types of agricultural crops grown in nurseries and greenhouses, such as ornamental plants and specialty fruits and vegetables.

  15. Effect of N and K Fertilizers on Yield and Quality of Greenhouse Vegetable Crops

    Institute of Scientific and Technical Information of China (English)

    LIU Zhao-Hui; JIANG Li-Hua; LI Xiao-Lin; R. H(A)RDTER; ZHANG Wen-Jun; ZHANG Yu-Lan; ZHENG Dong-Feng

    2008-01-01

    The application of large amounts of fertilizers, a conventional practice in northern China for the production of vegetable crops, generally leads to substantial accumulation of soil nutrients within a relatively short period of time. A fixed field experiment was designed to study the effects of nitrogen (N) and potassium (K) fertilizers applicd to optimize the yield and quality of typical vegetable crops. Application of N and K fertilizers significantly increased the yields of kidney bean.The largest yields were obtained in the first and second years after application of 1 500 kg N and 300 kg K2O ha-1. In the third year, however, there was a general decline in yields. Maximum yields occurred whcn intermediate rates of N and K (750 kg N and 300 kg K2O ha-1) were applied. However, no significant differences were observed in the concentrations of vitamin C (VC) in kidney bean among different years and various rates of fertilizer treatments. Yields of tomato grown in rotation after kidney bean showed significant responses to the application of N and K in the first year. In the second year,the yields of tomato were much lower. This suggested that the application of N fertilizer did not have any effect upon tomato yield, whereas application of K fertilizer did increase the yield. Application of K fertilizer was often associated with increased sugar concentrations.

  16. Repellency, toxicity, and oviposition inhibition of vegetable extracts against greenhouse whitefly Trialeurodes vaporariorum (Westwood (Hemiptera: Aleyrodidae

    Directory of Open Access Journals (Sweden)

    Edgar Eduardo Mendoza-Garcia

    2014-03-01

    Full Text Available In a search for sustainable options of greenhouse whitefly Trialeurodes vaporariorum (Westwood management, the toxic and/or repellent potential of water, ethanolic, and acetonic extracts of Ambrosia artemisiifolia L. (Asteraceae, Comocladia engleriana Loes (Anacardiaceae, Piper auritum Kunth (Piperaceae, Raphanus raphanistrum L. (Brassicaceae, and Taraxacum officinale F.H. Wigg. aggr.* (Asteraceae were evaluated. Repellency was assessed by the cylinder method (olfactometer, while toxicity and oviposition inhibition were assessed by the leaf immersion method. Acetonic extracts did not cause any repellent or insecticidal effect. In contrast, 200 mg mL-1 water and ethanolic extracts of R. raphanistrum and ethanolic extract of A. artemisiifolia had the highest repellent activity (76%, 72%, and 69%, respectively although their activity decreased gradually over time. Ethanolic extracts of P. auritum (66% and R. raphanistrum (56% at 200 mg mL¹ were highlighted as being toxic, while the most effective in inhibiting oviposition were water extracts of R. raphanistrum (76.1% and P. auritum (72.0% and ethanolic extract of P. auritum (69.5%; however, concentrations lower than 60 mg mL-1 caused oviposition stimulation. Our results suggest that water and ethanolic extracts of R. raphanistrum and P. auritum represent a useful tool in integrated whitefly management.

  17. A greenhouse and field-based study to determine the accumulation of arsenic in common homegrown vegetables grown in mining-affected soils.

    Science.gov (United States)

    Ramirez-Andreotta, Monica D; Brusseau, Mark L; Artiola, Janick F; Maier, Raina M

    2013-01-15

    The uptake of arsenic by plants from contaminated soils presents a health hazard that may affect home gardeners neighboring contaminated environments. A controlled greenhouse study was conducted in parallel with a co-created citizen science program (home garden experiment) to characterize the uptake of arsenic by common homegrown vegetables near the Iron King Mine and Humboldt Smelter Superfund site in southern Arizona. The greenhouse and home garden arsenic soil concentrations varied considerably, ranging from 2.35 to 533 mg kg(-1). In the greenhouse experiment four vegetables were grown in three different soil treatments and in the home garden experiment a total of 63 home garden produce samples were obtained from 19 properties neighboring the site. All vegetables accumulated arsenic in both the greenhouse and home garden experiments, ranging from 0.01 to 23.0 mg kg(-1) dry weight. Bioconcentration factors were determined and show that arsenic uptake decreased in the order: Asteraceae>Brassicaceae>Amaranthaceae>Cucurbitaceae>Liliaceae>Solanaceae>Fabaceae. Certain members of the Asteraceae and Brassicaceae plant families have been previously identified as hyperaccumulator plants, and it can be inferred that members of these families have genetic and physiological capacity to accumulate, translocate, and resist high amounts of metals. Additionally, a significant linear correlation was observed between the amount of arsenic that accumulated in the edible portion of the plant and the arsenic soil concentration for the Asteraceae, Brassicaceae, Amaranthaceae, and Fabaceae families. The results suggest that home gardeners neighboring mining operations or mine tailings with elevated arsenic levels should be made aware that arsenic can accumulate considerably in certain vegetables, and in particular, it is recommended that gardeners limit consumption of vegetables from the Asteraceae and Brassicaceae plant families.

  18. Vegetation, soil property and climatic controls over greenhouse gas fluxes in a blanket peatland hosting a wind farm

    Science.gov (United States)

    Armstrong, Alona; Waldron, Susan; Ostle, Nick; Whitaker, Jeanette

    2013-04-01

    Peatlands are important carbon (C) stores, with boreal and subarctic peatlands containing 15-30 % of the world soil carbon stock (Limpens et al., 2008). Research has demonstrated that greenhouse gas (GHG) fluxes in peatlands are influenced by vegetation, soil property and climatic variables, including plant functional type (PFT), water table height and temperature. In this paper we present data from Black Law Wind Farm, Scotland, where we examined the effect of a predicted wind turbine-induced microclimatic gradient and PFT on carbon dioxide (CO2) and methane (CH4) fluxes. Moreover, we determined the role of vegetation, soil property and climatic variables as predictors of the variation in CO2 and CH4 emissions. We measured CO2 and CH4 at 48 plots within Black Law Wind Farm at monthly intervals from May 2011 to April 2012. Four sampling sites were located along a predicted wind turbine-induced microclimatic gradient. At each site four blocks were established, each with plots in areas dominated by mosses, sedges and shrubs. Plant biomass and PFT (vegetation factors); soil moisture, water table height, peat depth, C content, nitrogen (N) content and C:N (soil properties); and soil temperature and photosynthetically active radiation (PAR) (climatic variables) were measured. Analysis of variance (ANOVA) models based on the microclimatic gradient site, PFT and season when measurements were made explained 58 %, 44 % and 49 % of the variation in ecosystem respiration, photosynthesis and CH4, respectively. Site, PFT, season and their interactions were all significant for respiration and photosynthesis (with the exception of the PFT*site interaction) but for CH4 only the main effects were significant. Parsimonious ANOVA models using the biotic, soil property and climatic explanatory data explained 62 %, 55 % and 49 % of the variation in respiration, photosynthesis and CH4, respectively. Published studies (Baidya Roy and Traiteur 2010; Zhou et al., 2012) and preliminary

  19. The Dynamic Greenhouse Challenge

    Science.gov (United States)

    Roman, Harry T.

    2010-01-01

    Greenhouses are marvelous devices, allowing one to enjoy the flower spectacle of summer all year round. At night, greenhouses use supplemental heat to keep the fragile plants warm. Over the last 30 years, greenhouse technology has undergone many changes, with the structures being automated and monitored and low-cost plastic structures emerging as…

  20. Soil contamination by phthalate esters in Chinese intensive vegetable production systems with different modes of use of plastic film.

    Science.gov (United States)

    Wang, Jun; Luo, Yongming; Teng, Ying; Ma, Wenting; Christie, Peter; Li, Zhengao

    2013-09-01

    The concentrations of six priority phthalic acid esters (PAEs) in intensively managed suburban vegetable soils in Nanjing, east China, were analyzed using gas chromatography-mass spectrometry (GC-MS). The total PAE concentrations in the soils ranged widely from 0.15 to 9.68 mg kg(-1) with a median value of 1.70 mg kg(-1), and di-n-butyl phthalate (DnBP), bis-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DnOP) were the most abundant phthalate esters. Soil PAE concentrations depended on the mode of use of plastic film in which PAEs were incorporated as plasticizing agents and both the plastic film and poultry manure appeared to be important sources of soil PAEs. Vegetables in rotation with flooded rice led to lower concentrations of PAEs in soil. The results indicate that agricultural plastic film can be an important source of soil PAE contamination and further research is required to fully elucidate the mechanisms of PAE contamination of intensive agricultural soils with different use modes of use of plastic film.

  1. Efficiency of a novel "Food to waste to food" system including anaerobic digestion of food waste and cultivation of vegetables on digestate in a bubble-insulated greenhouse.

    Science.gov (United States)

    Stoknes, K; Scholwin, F; Krzesiński, W; Wojciechowska, E; Jasińska, A

    2016-10-01

    At urban locations certain challenges are concentrated: organic waste production, the need for waste treatment, energy demand, food demand, the need for circular economy and limited area for food production. Based on these factors the project presented here developed a novel technological approach for processing organic waste into new food. In this system, organic waste is converted into biogas and digester residue. The digester residue is being used successfully as a stand-alone fertilizer as well as main substrate component for vegetables and mushrooms for the first time - a "digeponics" system - in a closed new low energy greenhouse system with dynamic soap bubble insulation. Biogas production provides energy for the process and CO2 for the greenhouse. With very limited land use highly efficient resource recycling was established at pilot scale. In the research project it was proven that a low energy dynamic bubble insulated greenhouse can be operated continuously with 80% energy demand reduction compared to conventional greenhouses. Commercial crop yields were achieved based on fertilization with digestate; in individual cases they were even higher than the control yields of vegetables such as tomatoes, cucumber and lettuce among others. For the first time an efficient direct use of digestate as substrate and fertilizer has been developed and demonstrated.

  2. Design of Intelligent Temperature and Humidity Control System for Vegetable Greenhouse%蔬菜大棚温湿度智能控制系统设计

    Institute of Scientific and Technical Information of China (English)

    梁万用; 王凯

    2009-01-01

    针对目前蔬菜大棚人工控制的不足,设计了蔬菜大棚温湿度智能控制系统.采用模糊控制理论,对 PID 参数进行实时校正,使系统控制性能处于最优控制状态,实现对蔬菜大棚温湿度的精确控制.试验和实际运行表明,该系统运行可靠,自动化程度高,有利于蔬菜大棚的智能化和统一化管理.%Aiming at the shortcoming of manual control of vegetable greenhouse at present, the intelligent temperature and humidity control system was designed for vegetable greenhouse.Using the fuzzy control theory, the real-time correction was carried on PID's parameters to make the system control capability in the most excellent state.The accurate control of temperature and humidity for vegetable greenhouse was realized.The results of running and experiment indicated that the system was reliable, with high automation degree.It is propitious to centralized and intellectualized management.

  3. Effects of plant tissue factors of the acceptance of four greenhouse vegetable host plants by the greenhouse whitefly: an electrical penetration graph (EPG) study

    NARCIS (Netherlands)

    Lei, H.; Lenteren, van J.C.; Xu, R.M.

    2001-01-01

    A combination of biological control and host-plant resistance is needed to control greenhouse whitefly, Trialeurodes vaporariorum (Westwood). The high level of susceptibility of several host plants to whitefly, based on their performance on these plants, is well documented. These studies only

  4. 新乡市大棚菜田土壤养分及盐分的演变%Evolution of soil nutrient and salts in vegetable field of greenhouse in Xinxiang

    Institute of Scientific and Technical Information of China (English)

    陈碧华; 孙丽; 李新峥; 王广印; 李亚灵

    2013-01-01

      为了研究大棚菜田土壤养分及盐分演变特征,采集了不同种植年限(0、5、10、15、20、25、30 a)的大棚菜田0~20、>20~40 cm土壤样品,测定了主要土壤养分指标、水溶性盐分以及土壤pH值。结果表明:新乡市大棚菜田土壤的培肥期在0~15 a,培肥后(15 a)土壤有机质质量分数在30 g/kg以上,达到较理想状态,碱解氮和速效磷含量表现为富集,质量分数分别在150、90 g/kg以上。但是速效钾却在100 g/kg以下,较缺乏,并且15 a以后还在继续流失。各养分含量随着土壤深度的增加逐渐下降。土壤碱解氮、速效磷含量与有机质呈极显著相关。新乡市大棚菜田土壤中氮磷钾的比例严重失调,出现磷素过量而钾素供应严重不足。土壤盐渍化从大棚种植15 a开始发生,与种植年限呈极显著正相关,并且与土壤pH值下降表现同步性。该研究结论期望给新乡市蔬菜大棚土壤的施肥决策提供参考。%The production history of greenhouse was more than 30 years in Muye vegetable production base in Henan Xinxiang. The main planting pattern of this region was wheat and maize rotation before building a greenhouse, but now it is the production of cucumbers and tomatoes in a greenhouse in spring and autumn. In order to study the evolution characteristics of soil fertility and salt of the vegetable field in the greenhouse, the soil sample of the vegetable field in the greenhouse (0-20,>20-40 cm) in different cultivating years (0, 5, 10, 15, 20, 25, and 30) were collected and the main soil fertility index and soluble salt and soil pH values were measured. The results showed that the fertilization period of plastic house soil in Xinxiang is usually around 15 age of cultivating where the content of organic matter therein is ideal, exceeding 30 g/kg. However, at the 15th cultivating years, the contents of alkali-hydrolyzable nitrogen and rapidly available

  5. Amazon Vegetation Response to Anomalously Dry and Wet Years 2010 and 2011 derived from Lower Troposphere Greenhouse Gas Balances

    Science.gov (United States)

    Gloor, E. U.; Gatti, L.; Miller, J. B.; Doughty, C.; Malhi, Y.; Basso, L. S.; Domingues, L. G.; Freitas, S. R.; Anderson, L. O.; Phillips, O. L.; Lloyd, J.

    2014-12-01

    Amazonia is potentially an important region for future changes of the global climate system because its vegetation, the rainforests, is a large 'labile' carbon pool. This is particularly so given that the Amazon is warming fast and its hydrological cycle is becoming more variable over the last three decades with an increasing frequency of both severe floods and comparably dry conditions. A diagnostic of the state of these forests is their carbon balance. To observe carbon and more generally greenhouse gas balances of the Basin under these changing conditions we have started regular bi-weekly vertical profile measurements using small aircraft at four strategically selected locations in the Basin in 2009. We will report results from these measurements using a simple air-mass back-trajectory based flux estimation approach. We will first focus on 2010, which was a dry year and 2011, which was an unusually wet year. During both years temperatures were elevated by 1 to 2 degrees C compared to the 1981-2011 mean. We find that during 2010 the Amazon Basin lost substantial amounts of carbon (~0.5 PgC) mainly via fires while in 2011 it was approximately in balance with fire losses balanced by forest carbon uptake. Comprehensive monthly biometric carbon pool measurements at a small set of forest plots suggest productivity stalled during drought months in 2010 and promoted losses by fires. Our results for the wetter year 2011 are consistent with estimates based on censuses at approximately 100 - 150 1ha forest plots distributed widely spread across the Basin. We will extend these results to 2013 and discuss implications of the results for the future of the Amazon rainforests in a warming and higher precipitation world as well as for the global carbon cycle.

  6. 设施蔬菜收获切割影响因素优化试验%Optimization experiment of influence factors on greenhouse vegetable harvest cutting

    Institute of Scientific and Technical Information of China (English)

    高国华; 王天宝; 周增产; 卜云龙

    2015-01-01

    为实现设施蔬菜收获机在收获过程中具有最佳的收获效果,该文设计了SHQG-I型设施蔬菜收获切割试验平台,该试验平台可对各个因素有效工作范围进行调整,采用响应曲面试验法对收获过程中刀具切割蔬菜茎部的切割综合影响因素进行优化。该文以奶油生菜为研究对象,根据奶油生菜的生长状况及种植情况,对收获切割的过程进行了分析,选取设施蔬菜的切割部位、切割方式、切削速度、削切角度、夹持距离、夹持角度6个参数作为影响因素,切割力大小作为试验指标,设计了SHQG-I型设施蔬菜收获切割试验平台。利用响应曲面试验法进行了试验,并利用Design-expert软件对试验结果进行分析,确定最优的工作参数:切削速度675 mm/s,削切角度4.85°,夹持距离98.5 mm,夹持角度64.5°。最终确定最优参数下的理论切割力为17.9 N,实际切割力为17.4 N,保证了收获成功率100%的情况下,有效降低了收获过程中切割力3~8 N/棵。该研究结果将用于温室蔬菜收获机的改进,同时对设施蔬菜收获提供参考。%In the developed countries of the West, the greenhouse vegetable industry has become highly mechanized, with a relatively stable mechanization production system and necessary supporting tools. In order to improve the efficiency of harvesting greenhouse vegetables, Beijing University of Technology has designed an innovative vegetable harvester. The cutting tool that is used to remove vegetables from their stems is a critical factor in greenhouse vegetable harvesting and must be optimized to ensure that greenhouse vegetables are harvested effectively. The designed machine can have a better harvest effect and reduce the wear of cutting tool in the process of the work. At present, the mechanical properties of stem-cutting factors affecting crops have been extensively studied with sugar cane, corn stalk

  7. Effects of straw and plastic film mulching on greenhouse gas emissions in Loess Plateau, China: A field study of 2 consecutive wheat-maize rotation cycles.

    Science.gov (United States)

    Chen, Haixin; Liu, Jingjing; Zhang, Afeng; Chen, Jing; Cheng, Gong; Sun, Benhua; Pi, Xiaomin; Dyck, Miles; Si, Bingcheng; Zhao, Ying; Feng, Hao

    2017-02-01

    Mulching practices have long been used to modify the soil temperature and moisture conditions and thus potentially improve crop production in dryland agriculture, but few studies have focused on mulching effects on soil gaseous emissions. We monitored annual greenhouse gas (GHG) emissions under the regime of straw and plastic film mulching using a closed chamber method on a typical winter-wheat (Triticum aestivum L. cv Xiaoyan 22) and summer-maize (Zea mays L. cv Qinlong 11) rotation field over two-year period in the Loess Plateau, northwestern China. The following four field treatments were included: T1 (control, no mulching), T2 (4000kgha(-1) wheat straw mulching, covering 100% of soil surface), T3 (half plastic film mulching, covering 50% of soil surface), and T4 (complete plastic film mulching, covering 100% of soil surface). Compared with the control, straw mulching decreased soil temperature and increased soil moisture, whereas plastic film mulching increased both soil temperature and moisture. Accordingly, straw mulching increased annual crop yields over both cycles, while plastic film mulching significantly enhanced annual crop yield over cycle 2. Compared to the no-mulching treatment, all mulching treatments increased soil CO2 emission over both cycles, and straw mulching increased soil CH4 absorption over both cycles, but patterns of soil N2O emissions under straw or film mulching are not consistent. Overall, compared to T1, annual GHG intensity was significantly decreased by 106%, 24% and 26% under T2, T3 and T4 over cycle 1, respectively; and by 20%, 51% and 29% under T2, T3 and T4 over cycle 2, respectively. Considering the additional cost and environmental issues associated with plastic film mulching, the application of straw mulching might achieve a balance between food security and GHG emissions in the Chinese Loess Plateau. However, further research is required to investigate the perennial influence of different mulching applications.

  8. Effects of Application of Biogas Slurry on the Form and Mobility of Soil Phosphorus in Vegetable Greenhouse Field

    Directory of Open Access Journals (Sweden)

    WANG Min-feng

    2017-06-01

    Full Text Available A packed soil column experiment was conducted to investigate the effects of biogas slurry on phosphorus(P form and mobility in a vegetable greenhouse soil with different P fertility levels. The results showed that application of biogas slurry all significantly reduced leachate volume and total phosphorus leaching in the experimental soil with different fertility levels. Compared with control treatments, the application of biogas slurry decreased total phosphorus content in leachate by 722.3 μg·column-1 through reducing leachate volume. Total inorganic phosphorus(TIP decreased by 507.2 μg·column-1 and 1 319 μg·column-1 in the moderate-P-fertility and high-P-fertility soil, respectively. Dissolved inorganic phosphorus(DIP was decreased by 158.1 μg·column-1 and 474.3 μg·column-1 in the low-P-fertility and moderate-P-fertility soil, respectively. In low-P-fertility soil, biogas slurry application significantly increased soil total P, Olsen-P and organic P in 0~7 cm soil depth by a proportion of 34.8%, 37.7% and 148%, respectively. It also reduced soil pH by 0.39 units. In 7~14 cm soil depth, biogas slurry application significantly increased soil total P, Olsen-P and organic P by a proportion of 18.5%, 29.3% and 32.9%, respectively. SoipH was also decreased by 0.28 units. In moderate-P-fertility soil, application of biogas slurry had no significantly influence on soil total P, but increased soil Olsen-P by 20.1% in 0~7 cm soil depth compared with control treatment. In 7~14 cm soil depth, application of biogas slurry reduced soil pH by 0.33 units. In high-P-fertility soil, application of biogas slurry had no significantly influence on soil total P, Olsen-P and organic P in 0~7 cm soil depth compared with control treatment. In 7~14 cm soil depth, application of biogas slurry reduced soil pH by 0.34 units. In conclusion, application of biogas slurry significantly increased different forms of phosphorus contents in low-P-fertility soil, however

  9. 中国南方塑料大棚气象灾害风险区划%Meteorological disaster greenhouse in risk zoning for plastic south China

    Institute of Scientific and Technical Information of China (English)

    杨再强; 朱凯; 赵翔; 张婷华; 彭晓丹; 周志龙

    2012-01-01

    This paper is to evaluate the meteorological disaster effect of the agricultural facilities in south China. Based on the meteorological data of 160 meteorological stations in 15 south provinces from 1990 to 2009, considering the main hazard factors such as temperature, sunlight, precipitation and wind speed, the meteorological disaster projection pursuit grade evaluation model of Southern Plastic Greenhouse was built using real-coded accelerating genetic algorithm. Then, monthly and seasonal risk levels of plastic greenhouse meteorological disasters were calculated and risk zoning for every season was conducted. Results show that in spring, Sichuan Basin is the lowest risk areas as the temperature rise rapidly, which is favorable to plant growth. Areas like Chongqing and Guizhou have the highest level of risk due to the less solar radiation ; in summer, coastal regions have high risks, because frequently occurred storms, typhoons and other natural disasters have a greater impact on the facility structure; in autumn, disaster risk is generally low, with rare high distribution; in winter, latitude 25°N is a dividing line, north of which is not suitable for the development of plastic greenhouse due to low temperature and sparse light conditions, and thus the disaster risk level is high. In contrast, regions at south of the line, the risk is low. In south China, the most suitable areas for the development of plastic greenhouses are west areas in autumn, south areas in winter, and Sichuan Basin in summer and spring. The results could provide a reference to the reasonable layout of the development of southern plastic greenhouse and the prevention of meteorological disasters.%利用中国南方地区15个省市自治区160个气象观测站台1990-2009年的气象资料,综合考虑气温、光照、风速、降水等主要致灾因子,并根据这些数据建立了基于实数编码的加速遗传算法的南方塑料大棚气象灾害的投影寻踪等级评价模型,

  10. Modeling water flow and nitrate dynamics in a plastic mulch vegetable cultivation system using HYDRUS-2D

    Science.gov (United States)

    Filipović, Vilim; Romić, Davor; Romić, Marija; Matijević, Lana; Mallmann, Fábio J. K.; Robinson, David A.

    2016-04-01

    Growing vegetables commercially requires intensive management and involves high irrigation demands and input of agrochemicals. Plastic mulch application in combination with drip irrigation is a common agricultural management technique practiced due to variety of benefits to the crop, mostly vegetable biomass production. However, the use of these techniques can result in various impacts on water and nutrient distribution in underlying soil and consequently affect nutrient leaching towards groundwater resources. The aim of this work is to estimate the effect of plastic mulch cover in combination with drip irrigation on water and nitrate dynamics in soil using HYDRUS-2D model. The field site was located in Croatian costal karst area on a Gleysol (WRB). The experiment was designed according to the split-plot design in three repetitions and was divided into plots with plastic mulch cover (MULCH) and control plots with bare soil (CONT). Each of these plots received applications of three levels of nitrogen fertilizer: 70, 140, and 210 kg per ha. All plots were equipped with drip irrigation and cropped with bell pepper (Capsicum annuum L. cv. Bianca F1). Lysimeters were installed at 90 cm depth in all plots and were used for monitoring the water and nitrate outflow. HYDRUS-2D was used for modeling the water and nitrogen outflow in the MULCH and CONT plots, implementing the proper boundary conditions. HYDRUS-2D simulated results showed good fitting to the field site observed data in both cumulative water and nitrate outflow, with high level of agreement. Water flow simulations produced model efficiency of 0.84 for CONT and 0.56 for MULCH plots, while nitrate simulations showed model efficiency ranging from 0.67 to 0.83 and from 0.70 to 0.93, respectively. Additional simulations were performed with the absence of the lysimeter, revealing faster transport of nitrates below drip line in the CONT plots, mostly because of the increased surface area subjected to precipitation

  11. 德州市蔬菜生产型日光温室优化设计%Optimal Design of Vegetable Greenhouse in Dezhou City

    Institute of Scientific and Technical Information of China (English)

    高方胜; 王磊; 王明友

    2015-01-01

    针对德州市目前日光温室应用中普遍存在的结构不合理、建造技术落后、生产性能较差等问题,在理论设计的基础上,立足德州,本着科学合理、尊重实际、易于建造、成本经济、便于管理的原则对德州市蔬菜生产型日光温室进行了优化设计。通过对日光温室墙体材料、后屋面材料、前屋面支撑及骨架材料、覆盖材料等的合理选择,以及对日光温室长度、净宽度、屋脊和后墙高度、墙厚度、后屋面仰角、前屋面角、下挖深度的优化设计,使日光温室的温度环境得到较大改善,最低气温和最低地温分别提高35.0%~237.5%和21.4%~142.9%,保证了温室内蔬菜生产的正常进行。%Aiming at the problems of unreasonable structure,outdated building technology and poor pro-ductivity of greenhouse in Dezhou City,the optimal design of vegetable greenhouse was carried out based on the theoretical design and Dezhou status,and according to the principles of scientific and reasonable,respect-ing facts,easy to build,low cost and easy to manage.The wall,back -roof materials,supporting and frame-work materials before the roof and cover materials were chosen reasonably.The length,net width,height of ridge and back -wall,wall thickness,angle of elevation of back -roof,angle before the roof,and digging depth of greenhouse were optimized.Then,the temperature environment status closely related to productivity of greenhouse was improved greatly,and the lowest air temperature and soil temperature increased by 35.0% ~237.5% and 21 .4% ~1 42.9% respectively,which could assure normal vegetable production in greenhouse.

  12. Combined effects of enhanced ultraviolet-B radiation and doubled CO2 concentration on growth,fruit quality and yield of tomato in winter plastic greenhouse

    Institute of Scientific and Technical Information of China (English)

    LI Fangmin; WANG Jun; CHEN Yuping; ZOU Zhirong; WANG Xunling; YUE Ming

    2007-01-01

    Five different doses of ultraviolet-B (UV-B)radiation were supplied to tomato (Lycopersicon esculeutum.in the winter plastic greenhouse.The influences on the seedling growth,fruit quality and yield of tomato were investigated.Results showed that the seedling growth,and the contents of UV absorbing compounds,soluble sugar,organic acid,vitamin C and lycopene of tomato fruits,and yield of tomato increased under doubled CO2 concentration.Under the doubled CO2 concentration the effects of lost doses of UV-B radiation could further promote the effects of doubled CO:concentration.However,there is no significant increase in yield of tomato.The best dose of UV-B radiation is about 1.163 kJ.m-2.When the dose of UV-B radiation is more than it,the effects of UV-B will be reduced.

  13. Application of Na2SO4·10H2O thermal energy storage materials in the vegetable greenhouse%十水硫酸钠储热材料在农业大棚中的应用

    Institute of Scientific and Technical Information of China (English)

    徐燕; 刘伟; 于观成; 王智军; 黄学金

    2011-01-01

    就蔬菜大棚夜间需要提升温度的需求,提出使用储热材料的基本设想.经对不同的储热材料进行对比分析,决定采用Na2SO4.10H20作为实验用储热材料.实验结果证明,在晴天,该储热材料白天储存的太阳能可使塑料大棚内日平均气温提高2.4℃,夜间平均气温提高5.4 ℃.%In order to raise the temperature of vegetable greenhouse since its temperature might be low at night,the basic idea of using thermal energy storage material was proposed.To make comparative analysis of different thermal energy storage materials, Na2SO4 · 10H2O is used as experimental materials for thermal storage.Thermal energy storage materials store excess solar energy during the day, increasing the average temperature of plastic canopy to 2.4 ℃, the average night temperature to 5.4 ℃.

  14. Vegetation

    DEFF Research Database (Denmark)

    Epstein, H.E.; Walker, D.A.; Bhatt, U.S.;

    2012-01-01

    • Over the past 30 years (1982-2011), the Normalized Difference Vegetation Index (NDVI), an index of green vegetation, has increased 15.5% in the North American Arctic and 8.2% in the Eurasian Arctic. In the more southern regions of Arctic tundra, the estimated aboveground plant biomass has...

  15. Attempts to reduce exposure to fungi, β-glucan, bacteria, endotoxin and dust in vegetable greenhouses and a packaging unit.

    Science.gov (United States)

    Madsen, Anne Mette; Tendal, Kira; Frederiksen, Margit W

    2014-01-15

    Indoor handling of large amounts of plant materials occurs in different occupational settings including greenhouses and causes exposure to bioaerosols. The bioaerosol components fungi, β-glucan, bacteria and endotoxin are involved in different airway symptoms and health effects can be dose-dependent. Therefore, there is a persistent need to reduce exposure. The aims of this study were to identify tasks causing exposure and to evaluate preventive measures aimed at reducing exposure of greenhouse workers to bioaerosols, and to study factors affecting the exposure. We have focused on different exposure scenarios; one with high short-term exposure found during clearing of old cucumber plants; the other with long-term, mid-level exposure found during tomato picking, leaf nipping, stringing up tomato plants, and packaging of cucumbers. Clearing of non-dried cucumber plants compared with clearing of dried cucumber plants significantly reduced the exposure to dust, endotoxin, bacteria, fungal spores and β-glucan. More endotoxin and fungi are emitted and more of the emitted particles were of respirable size if the leaves were dried. Along the cucumber packaging line, exposure levels were highly specific to each personal subtask. The subtask 'unloading of cucumbers' was the source of exposure making task ventilation or shielding of the process a possibility. Elimination of leaf debris on the floor reduced the exposure to fungi significantly. However, leaf debris on the floor did not contribute significantly to the exposure to dust, endotoxin and bacteria. Furthermore, to eliminate leaf debris, it had to be cleared away and this was associated with a higher exposure to dust and endotoxin. The age of the plants affected the exposure level to bioaerosols with higher exposures from old plants. In conclusion, different tasks and subtasks cause very different exposure levels. It is possible to reduce exposure by identifying subtasks causing the exposure and by modifying work

  16. The impact of exogenous N supply on soluble organic nitrogen dynamics and nitrogen balance in a greenhouse vegetable system.

    Science.gov (United States)

    Liang, Bin; Kang, Lingyun; Ren, Tao; Junliang, Li; Chen, Qing; Wang, Jingguo

    2015-05-01

    A long-term greenhouse experiment (2004-2012) was conducted with continuous tomato (Lycopersicum esculentum Mill.) plantings to understand the influence of an exogenous nitrogen supply from irrigation water, chemical fertilizer, or organic amendment on the N balance and soluble organic nitrogen (SON). The results from 16 tomato growing seasons indicated that the application of organic amendment (manure and straw) alone (Or-N) resulted in the same yield as the conventional chemical N with organic amendment (Co-N) and the reduced chemical N with organic amendment (Re-N) treatments. The annual apparent N loss was >1000 and 438 kg N ha(-1) in the Co-N and Re-N treatments, respectively. Over the study period, the SON in the 1.8 m soil profile was 1449 and 1978 kg N ha(-1) in the Re-N and Co-N treatments, respectively, it was 1.7- and 2.3-fold higher than that observed in the Or-N treatment, which indicated that SON increased with the chemical N application. The percentage of SON in the cumulative soluble N (SON plus mineral N) ranged from 28% to 44%, and there were no significant differences across the 0-0.6, 0.6-1.2, and 1.2-1.8 m soil profile, which indicated that the leaching and distribution of SON was similar to those of the mineral N in the 0-1.8 m soil profile. We conclude that the mobility of soluble organic N in the 0-1.8 m of the soil was synchronous with the mineral N under a greenhouse production system, and the risk of soluble organic N leaching increased with inorganic N application rate. Therefore, leaching of SON in the intensive agriculture should not be ignored when evaluating the risk of N leaching.

  17. Fertilization of Watermelon Grown with Wheat Straw Substrate in Passive Plastic Greenhouse%大棚西瓜秸秆基质栽培施肥量研究

    Institute of Scientific and Technical Information of China (English)

    袁培祥

    2013-01-01

    Fertilization was studied using watermelon "Xiuli' grown in wheat straw substrate in passive plastic greenhouse. The tests included 5 levels of chicken manure + ammonium phosphate. The measurements included plant growth, yield and fruit quality. With the levels tested in this experiment yield was increased with the increase of fertilizer amount, the best treatment was 30 kg chicken manure + 1.5 kg ammonium phosphate per plot(19.87 m2).%以西瓜品种秀丽为试材,在大棚中采用秸秆基质栽培,腐熟鸡粪+磷酸二铵作为施肥配方,分析比较了5种施肥量对西瓜生长发育、产量及品质的影响,结果表明,在一定施肥量的范围内,产量随施肥量的增加而增加,综合所有因素,最佳施肥配方为每小区腐熟鸡粪30 kg+磷酸二铵1.5 kg.

  18. Energy consumption for different greenhouses' structures

    Directory of Open Access Journals (Sweden)

    Đević Milan

    2008-01-01

    Full Text Available In this paper influence of greenhouses' structure was estimated for four different double plastic covered greenhouses in winter lettuce production. Plastic coverings are introduced as mean of making this kind of plant production more efficient. Also, as a mean of lowering energy consumption, the tunnel structures are proposed. Four different double plastic covered greenhouses were used for energy analysis. Two tunnel types, 9 x 58m and 8 x 25m covered with double PE folia, and two gutter connected plastic covered greenhouses. One greenhouse is 2 x 7 m wide and 39 m long and the other 20 x 6.4 m wide and 42 m long. Results have shown the lowest energy consumption for gutter connected greenhouses. Energy out/in ratio was also higher in gutter connected greenhouse. Highest energy consumption was obtained in tunnel greenhouse 8 x 25m.

  19. Effects of CO[sub 2] concentration on photosynthesis, transpiration and production of greenhouse fruit vegetable crops

    Energy Technology Data Exchange (ETDEWEB)

    Nederhoff, E.M.

    1994-10-25

    The effect of the CO[sub 2] concentration of the greenhouse air (C) in the range 200 to 1100 [mu]mol mol[sup -1] was investigated in tomato (Lycopersicon esculentum Mill.), cucumber (Cucumis sativus L.), sweet pepper (Capsicum annuum L.) and eggplant (Solanum melongena L.), grown in greenhouses. The effect of C on canopy net photosynthetic CO[sub 2] assimilation rate (or photosynthesis, P) was expressed by a set of regression equations, relating P to PAR, C and LAI. A rule of thumb ('CO[sub 2]-rule') was derived, approximating the relative increase of P caused by additional CO[sub 2] at a certain C. This CO[sub 2]-rule is: X = (1000/C)[sup 2] * 1.5 (X in % per 100 [mu]mol[sup -1], and C in [mu]mol mol[sup -1]). Two models for canopy photosynthesis were examined by comparing them with the experimental photosynthesis data. No 'midday depression' in P was observed. The effects of C on leaf conductance (g) and on rate of crop transpiration (E) were investigated. An increase of 100 I[mu]mol mol[sup -1] ' in C reduced g by about 3-4% in sweet pepper, tomato and cucumber and by about 11% in eggplant. The effect of C on E was analyzed by combining the regression equation for g with the Penman-Monteith equation for E. C had only a relatively small effect on E, owing to thermal and hydrological feedback effects. The decoupling of g and E was quantified. No time-dependent variation or 'midday depression' in E was observed, and no significant effect of C on average leaf temperature was established. In five experiments, the effect of C on growth and production and on specific features were analyzed; fruit production (dry weight) was most affected by C in sweet pepper; fresh weight fruit production per unit CO[sub 2] was highest in cucumber; fruit quality was not influenced by C. High C promoted the 'short leaves syndrome' in tomato and 'leaf tip chlorosis' in eggplant, probably related to calcium and boron translocation

  20. Utilização de diferentes filmes plásticos como cobertura de abrigos para cultivo protegido = Use of different greenhouses plastic film as cover

    Directory of Open Access Journals (Sweden)

    José Weselli de Sá Andrade

    2011-07-01

    radiation in field open. Theprotected environment reduced, in relation to the open field, the density of flow of solar radiation, with higher intensity in the shelter covered with thermal plastic film lightdiffuser. The greatest effect of shelters occurred on the maximum temperature, with highervalues the greenhouse covered with a conventional polyethylene film. There were no differences for air relative humidity between greenhouses. The black plastic mulching increased the soil temperature at 6 and 12 cm depth.

  1. Vegetation

    DEFF Research Database (Denmark)

    Epstein, H.E.; Walker, D.A.; Bhatt, U.S.

    2012-01-01

    increased 20-26%. • Increasing shrub growth and range extension throughout the Low Arctic are related to winter and early growing season temperature increases. Growth of other tundra plant types, including graminoids and forbs, is increasing, while growth of mosses and lichens is decreasing. • Increases...... in vegetation (including shrub tundra expansion) and thunderstorm activity, each a result of Arctic warming, have created conditions that favor a more active Arctic fire regime....

  2. Measuring calcium, potassium, and nitrate in plant nutrient solutions using ion-selective electrodes in hydroponic greenhouse of some vegetables.

    Science.gov (United States)

    Vardar, Gökay; Altıkatoğlu, Melda; Ortaç, Deniz; Cemek, Mustafa; Işıldak, İbrahim

    2015-01-01

    Generally, the life cycle of plants depends on the uptake of essential nutrients in a balanced manner and on toxic elements being under a certain concentration. Lack of control of nutrient levels in nutrient solution can result in reduced plant growth and undesired conditions such as blossom-end rot. In this study, sensitivity and selectivity tests for various polyvinylchloride (PVC)-based ion-selective membranes were conducted to identify those suitable for measuring typical concentration ranges of macronutrients, that is, NO(3-), K(+), and Ca(2+), in hydroponic solutions. The sensitivity and selectivity of PVC-membrane-based ion-selective sensors prepared with tetradodecylammoniumnitrate for NO(3-), valinomycin for K(+), and Ca ionophore IV for Ca(2+) were found to be satisfactory for measuring NO(3-), K(+), and Ca(2+) ions in nutrient solutions over typical ranges of hydroponic concentrations. Potassium, calcium, and nitrate levels that were utilized by cucumber and tomato seedlings in the greenhouse were different. The findings show that tomato plants consumed less amounts of nitrate than cucumber plants over the first 2 months of their growth. We also found that the potassium intake was higher than other nutritional elements tested for all plants. © 2014 International Union of Biochemistry and Molecular Biology, Inc.

  3. 基于nRF2401的藏区蔬菜大棚管理系统的设计与实现%Design and realization of Tibetan vegetable greenhouse management system based on nRF2401

    Institute of Scientific and Technical Information of China (English)

    边巴旺堆; 代森; 张巧玲; 益西拉姆

    2013-01-01

    Vegetable greenhouse plays an indispensable role in the Tibetan vegetable supply; to capacitate peasants manage vegetable greenhouses more expediently, and enable the vegetable greenhouse to get a widespread popularization, the paper, combining nRF2401 wireless transmission with SPCE061A single chip microcomputer, realized the design of Tibetan intelligent vegetable greenhouse management system. Relevant sensors controlled by SPCE061A are taken advantage of to samples data of indicators such as temperature, carbon dioxide concentration in the vegetable greenhouse, and then transmit sampling data by nRF2401 wireless models; the background center will display the spot data on the LCD in time, and when the indicators go over appropriate values, the system wiD give users a speech warning. There are many advantages in The Tibetan vegetable greenhouse management system. For instance, sensitive monitor, convenient operation, display of both Tibetan and Chinese interfaces, speech warning of both Tibetan and Chinese etc.%蔬菜大棚在西藏的蔬菜供应中起着不可或缺的作用,为方便农户对蔬菜大棚的管理,使蔬菜大棚在藏区得到广泛的推广,文中结合nRF2401无线传输[1]和SPCE061A单片机[2]实现了藏区蔬菜大棚管理系统的设计.本项目通过SPCE061A单片机控制相关传感器进行蔬菜大棚内温度、二氧化碳浓度等指标采集,然后将采集的数据通过nRF2401进行传输;后台中心将接收的前台数据在LCD上实时显示出来,并当指标超过了适宜值时,系统便会对农户进行语音提示.本文设计的藏区蔬菜大棚管理系统具有监测灵敏、可操作性强、藏汉双语界面显示、双语报警等优点.

  4. Effects of Herbicides on Greenhouse Gases Emission from Vegetable Plantation Soil%除草剂对土壤温室气体排放的影响

    Institute of Scientific and Technical Information of China (English)

    丁洪; 郑祥洲; 雷俊杰; 张玉树; 陈静蕊; 李世清

    2012-01-01

    试验设对照、尿素、尿素+草甘膦和尿素+丁草胺4个处理,尿素氮用量为200 mg·kg-1干土,除草剂用量为10 mg有效成分·kg-1干土.在实验室恒温培养条件下,研究除草剂对菜田土壤温室气体排放的影响.结果表明,菜田土壤中施用氮肥显著增加了温室气体N2O、CO2和CH4的排放.尿素氮肥中添加草甘膦显著抑制N2O、CO2的排放,分别比尿素处理降低48.4%和20.2%;添加丁草胺显著抑制N2O排放,比尿素处理降低23.2%,对CO2排放略有减少但不显著;草甘膦和丁草胺对CH4排放都无明显影响.这说明除草剂对土壤温室气体的排放具有显著影响,但不同除草剂品种的效应也存在明显差异.因此,在农田温室气体排放估算时应考虑除草剂的施用对温室气体减排所产生的效果.%To assess the effects of herbicides on greenhouse gases emission from vegetable plantation soil, an incubation experiment was conducted under laboratory condition with 4 treatments including control, urea, urea+glyphosate and urea+butachlor, and 200 mgN·kg-1 dry soil and 10 mg active ingredient·kg-1 dry soil were applied in urea and herbicides treatments respectively. The experimental results showed that nitrogen fertilizer greatly increased greenhouse gases N2O、CO2 and CH4 emission from the soil, but glyphosate reduced N2O and CO2 emission by 48.4% and 20.2% contrast to urea treatment respectively; butachlor reduced N2O emission 23.2%, not significantly reduced CO2 emission; however, glyphosate and butachlor had no effect on CH4 emission. These indicated the effective influences and the differences of different herbicides on greenhouse gases emission. Therefore, effects of herbicides on greenhouse gases emission should be taken into account in estimation of total greenhouse gases emission amount from agricultural soils in the future.

  5. MIGRATION OF PHTHALATES FROM PLASTIC TANK TO VEGETABLE OIL AS A PART OF FEEDING MIXTURES USED FOR CHICKEN BROILERS FATTENING

    Directory of Open Access Journals (Sweden)

    Pavel Suchý

    2010-05-01

    Full Text Available The concentrations of phthalic acid esters (PAEs as di-n-butyl phthalate (DBP and di-2-ethylhexyl phthalate (DEHP were measured in samples of rapeseed oil, which was used as a feed. First samples were collected during the production process and second after the storage in plastic tank (21 days. The results of measurements are that there is 2.93-10.10 mg PAEs.kg-1 in the oil before storage and 22.73-61.55 mg PAEs.kg-1 after storage. For the monitoring of distribution and accumulation of PAEs in animal tissues and organs (muscles, adipose tissue, skin and liver broiler chicks ROSS 308 were used. The chicks were divided into 4 groups (50 chicks each. All the chicks were fed by commercial diets (complete feed, KKS for broiler chicks (starter – BR1; grower – BR2 and finisher – BR3. The experimental diets were supplemented with vegetable oil (RO with low (group N or high (group V phthalate content, or animal fat with high phthalate content (group Z. Neither the control diets (K nor the grower (BR1 diets contained vegetable oil or animal fat. DBP and DEHP were found in all tissues of all chicks. The highest concentration of DBP of 1.28 1.00 mg.kg-1 of fresh sample (an average value from 8 chicks was determined in the adipose tissue of V chicks. The highest concentration of DEHP of 3.27 2.87 mg.kg-1 of fresh sample (average of 8 chicks was also determined in the V group. doi:10.5219/49

  6. Plant Growth-Promoting Rhizobacteria Inoculation to Enhance Vegetative Growth, Nitrogen Fixation and Nitrogen Remobilisation of Maize under Greenhouse Conditions.

    Directory of Open Access Journals (Sweden)

    Khing Boon Kuan

    Full Text Available Plant growth-promoting rhizobacteria (PGPR may provide a biological alternative to fix atmospheric N2 and delay N remobilisation in maize plant to increase crop yield, based on an understanding that plant-N remobilisation is directly correlated to its plant senescence. Thus, four PGPR strains were selected from a series of bacterial strains isolated from maize roots at two locations in Malaysia. The PGPR strains were screened in vitro for their biochemical plant growth-promoting (PGP abilities and plant growth promotion assays. These strains were identified as Klebsiella sp. Br1, Klebsiella pneumoniae Fr1, Bacillus pumilus S1r1 and Acinetobacter sp. S3r2 and a reference strain used was Bacillus subtilis UPMB10. All the PGPR strains were tested positive for N2 fixation, phosphate solubilisation and auxin production by in vitro tests. In a greenhouse experiment with reduced fertiliser-N input (a third of recommended fertiliser-N rate, the N2 fixation abilities of PGPR in association with maize were determined by 15N isotope dilution technique at two harvests, namely, prior to anthesis (D50 and ear harvest (D65. The results indicated that dry biomass of top, root and ear, total N content and bacterial colonisations in non-rhizosphere, rhizosphere and endosphere of maize roots were influenced by PGPR inoculation. In particular, the plants inoculated with B. pumilus S1r1 generally outperformed those with the other treatments. They produced the highest N2 fixing capacity of 30.5% (262 mg N2 fixed plant-1 and 25.5% (304 mg N2 fixed plant-1 of the total N requirement of maize top at D50 and D65, respectively. N remobilisation and plant senescence in maize were delayed by PGPR inoculation, which is an indicative of greater grain production. This is indicated by significant interactions between PGPR strains and time of harvests for parameters on N uptake and at. % 15Ne of tassel. The phenomenon is also supported by the lower N content in tassels of maize

  7. Plant Growth-Promoting Rhizobacteria Inoculation to Enhance Vegetative Growth, Nitrogen Fixation and Nitrogen Remobilisation of Maize under Greenhouse Conditions.

    Science.gov (United States)

    Kuan, Khing Boon; Othman, Radziah; Abdul Rahim, Khairuddin; Shamsuddin, Zulkifli H

    2016-01-01

    Plant growth-promoting rhizobacteria (PGPR) may provide a biological alternative to fix atmospheric N2 and delay N remobilisation in maize plant to increase crop yield, based on an understanding that plant-N remobilisation is directly correlated to its plant senescence. Thus, four PGPR strains were selected from a series of bacterial strains isolated from maize roots at two locations in Malaysia. The PGPR strains were screened in vitro for their biochemical plant growth-promoting (PGP) abilities and plant growth promotion assays. These strains were identified as Klebsiella sp. Br1, Klebsiella pneumoniae Fr1, Bacillus pumilus S1r1 and Acinetobacter sp. S3r2 and a reference strain used was Bacillus subtilis UPMB10. All the PGPR strains were tested positive for N2 fixation, phosphate solubilisation and auxin production by in vitro tests. In a greenhouse experiment with reduced fertiliser-N input (a third of recommended fertiliser-N rate), the N2 fixation abilities of PGPR in association with maize were determined by 15N isotope dilution technique at two harvests, namely, prior to anthesis (D50) and ear harvest (D65). The results indicated that dry biomass of top, root and ear, total N content and bacterial colonisations in non-rhizosphere, rhizosphere and endosphere of maize roots were influenced by PGPR inoculation. In particular, the plants inoculated with B. pumilus S1r1 generally outperformed those with the other treatments. They produced the highest N2 fixing capacity of 30.5% (262 mg N2 fixed plant-1) and 25.5% (304 mg N2 fixed plant-1) of the total N requirement of maize top at D50 and D65, respectively. N remobilisation and plant senescence in maize were delayed by PGPR inoculation, which is an indicative of greater grain production. This is indicated by significant interactions between PGPR strains and time of harvests for parameters on N uptake and at. % 15Ne of tassel. The phenomenon is also supported by the lower N content in tassels of maize treated with

  8. Effect of soil solarization on tomato inside plastic greenhouse Efeito da solarização do solo sobre o tomateiro em entufa plástica

    Directory of Open Access Journals (Sweden)

    Nereu Augusto Streck

    1995-01-01

    Full Text Available The effect of soil covering with transparent polyethylene sheets, known as soil solarization, on tomate crop insule a 10m x 25m plastic greenhouse was evaluated in the Subtropical Central Region of the Rio Grande do Sul State, Brazil. A 80-day solarization pre-planting treatment from December 17, 1992 to March 7, 1993 significantly enhanced marketable fruit weight of "Monte Carlo" tornato variety (91% increase. A large increase was observed in plant growth response resulted by solarization, even in the absence of known pathogens. Differences in chemical soil properties were not detected.Este experimento foi conduzido para avaliar o efeito da solarização do solo sobre a cultura do tomateiro, cultivar "Monte Carlo", no interior de uma estufa plástica de 10m x 25m, em Santa Maria, RS. A solarização foi realizada de 17 de dezembro de 1992 a 07 de março de 1993, utilizando polietileno transparente de 100µm de espessura. Quatro parcelas de 6m x 4m foram solarizadas e outras quatro parcelas de mesmo tamanho foram mantidas sem plástico, constituindo a testemunha. Não foi verificada modificação nas propriedades químicas do solo com a solarização. O crescimento inicial das plantas foi maior nas parcelas solarizadas e como consequência, atingiram a altura de poda uma semana antes do que nas parcelas não solanzadas. A produção comercial de frutos foi 91% superior nas parcelas solarizadas. Evidenciou-se, portanto, o efeito positivo do método da solarização do solo sobre o tomateiro em estufa plástica.

  9. 南方双层塑料大棚智能增温器的研制及试验%Development and test of intelligent heating device for double-layer plastic greenhouse in South China

    Institute of Scientific and Technical Information of China (English)

    潘永地; 姚益平; 林建忠

    2013-01-01

    Plastic-covered greenhouses have become have become popular as a main method in protected horticulture in China, and their area has increased a lot. The plants were mostly thermophilic crops in greenhouses. These crops are vulnerable to freezing injury. For this reason, it is very important to study how to prevent freezing injury of these crops in greenhouses in winter. In order to develop a new tool for preventing freezing injury in plastic film greenhouses in southern China, a intelligent warming device for plastic-film greenhouses was designed and evaluated. Its structure mainly includes a control circuit board, temperature sensor, fuel tank, ignition system, wick, and other components. After this system was connected to a workstation, its temperature sensor can collect temperature in real time, and send it to micro-controller unit in the control circuit board. After these temperature data were analyzed by a program in the micro controller, a rotating signal was sent to the micro motor that drives the device cover. The cover of the warming device will automatically open until the temperature in plastic film greenhouse decreased to the set starting temperature in the micro control unit, which can be set beforehand. Generally, the set starting temperature was slightly higher than the critical temperature for freezing injury. After the cover opens, the ignition system kindles the asbestos wicks, which absorb fuel from the tank. Thus, the device releases its heat until the temperature increases to the extinction temperature set beforehand. In order to ensure device reliability, the ignition system keeps working until the wick s ignited or the ignition system starts 3 times. The device was made of iron, and it was designed to seal. It is safe for the device to work on any alcohol level in tank. A 7.4V lithium battery was used to power the device. With this power, the device is portable, it can work at any field site without line electricity. In southern China, the

  10. 湘中地区大棚蔬菜信息化进程及其对策%Problem and Strategies of Informatization of Greenhouse Vegetables in Central Hunan

    Institute of Scientific and Technical Information of China (English)

    王会; 周桃云; 梁平元

    2016-01-01

    Firstly,this article analyzes the current domestic and overseas state of informatization of green-house vegetables.The development and present problems in greenhouse vegetables informatization in central Hunan are emphatically analyzed.Accordingly,specific solutions are proposed.Finally,the opti-mization ideas of intelligent planting and intelligent control model using WSNs technology are proposed.%分析了国内外温室大棚蔬菜信息化发展的现状,阐述了湘中地区温室大棚蔬菜信息化的进程,对其中存在的问题进行了分析,并提出了具体的解决对策,并构建了蔬菜智能化种植的优化思想与 WSNs智能控制系统模型。

  11. The Greenhouse effect: impacts of ultraviolet-B (UV-B) radiation, carbon dioxide (CO2), and ozone (O3) on vegetation.

    Science.gov (United States)

    Krupa, S V; Kickert, R N

    1989-01-01

    radiative cloud forcing. The effects of UV-B, CO2 and O3 on plants have been studied under growth chamber, greenhouse and field conditions. Few studies, if any, have examined the joint effects of more than one variable on plant response. There are methodological problems associated with many of these experiments. Thus, while results obtained from these studies can assist in our understanding, they must be viewed with caution in the context of the real world and predictions into the future. Biomass responses of plants to enhanced UV-B can be negative (adverse effect); positive (stimulatory effect) or no effect (tolerant). Sensitivity rankings have been developed for both crop and tree species. However, such rankings for UV-B do not consider dose-response curves. There are inconsistencies between the results obtained under controlled conditions versus field observations. Some of these inconsistencies appear due to the differences in responses between cultivars and varieties of a given plant species; and differences in the experimental methodology and protocol used. Nevertheless, based on the available literature, listings of sensitive crop and native plant species to UV-B are provided. Historically, plant biologists have studied the effects of CO2 on plants for many decades. Experiments have been performed under growth chamber, greenhouse and field conditions. Evidence is presented for various plant species in the form of relative yield increases due to CO2 enrichment. Sensitivity rankings (biomass response) are agein provided for crops and native plant species. However, most publications on the numerical analysis of cause-effect relationships do not consider sensitivity analysis of the mode used. Ozone is considered to be the most phytotoxic regional scale air pollutant. In the pre-occupation of loss in the O3 column, any increases in tropospheric O3 concentrations may be undermined relative to vegetation effects. As with the other stress factors, the effects of O3 have been

  12. Does morphological and anatomical plasticity during the vegetative stage make wheat more tolerant of water deficit stress than rice?

    Science.gov (United States)

    Kadam, Niteen N; Yin, Xinyou; Bindraban, Prem S; Struik, Paul C; Jagadish, Krishna S V

    2015-04-01

    Water scarcity and the increasing severity of water deficit stress are major challenges to sustaining irrigated rice (Oryza sativa) production. Despite the technologies developed to reduce the water requirement, rice growth is seriously constrained under water deficit stress compared with other dryland cereals such as wheat (Triticum aestivum). We exposed rice cultivars with contrasting responses to water deficit stress and wheat cultivars well adapted to water-limited conditions to the same moisture stress during vegetative growth to unravel the whole-plant (shoot and root morphology) and organ/tissue (root anatomy) responses. Wheat cultivars followed a water-conserving strategy by reducing specific leaf area and developing thicker roots and moderate tillering. In contrast, rice 'IR64' and 'Apo' adopted a rapid water acquisition strategy through thinner roots under water deficit stress. Root diameter, stele and xylem diameter, and xylem number were more responsive and varied with different positions along the nodal root under water deficit stress in wheat, whereas they were relatively conserved in rice cultivars. Increased metaxylem diameter and lower metaxylem number near the root tips and exactly the opposite phenomena at the root-shoot junction facilitated the efficient use of available soil moisture in wheat. Tolerant rice 'Nagina 22' had an advantage in root morphological and anatomical attributes over cultivars IR64 and Apo but lacked plasticity, unlike wheat cultivars exposed to water deficit stress. The key traits determining the adaptation of wheat to dryland conditions have been summarized and discussed. © 2015 American Society of Plant Biologists. All Rights Reserved.

  13. Fertilidade do solo e rendimento do tomateiro em estufa de plástico Soil fertility and tomato yield under plastic greenhouses

    Directory of Open Access Journals (Sweden)

    Juceli Vicente Rigue Veduim

    1998-06-01

    Full Text Available O objetivo deste experimento foi avaliar a resposta à adubação mineral do tomateiro cultivado no interior de estufa de plástico em solo Podzólico vermelho-amarelo de textura média e também avaliar a fertilidade do solo nas estufas da região de abrangendo da Emater Regional de Santa Maria. Os tratamentos consistiram de 0, 1, 3 e 5 vezes a recomendação de adubação, no delineamento experimental inteiramente casualizado, com quatro repetições. O experimento foi realizado em dois períodos, com semeaduras em 19 de agosto de 1995 (período inverno-primavera e 3 de fevereiro de 1996 (período outono-inverno. Utilizou-se o híbrido Monte Carlo do grupo Salada, com hábito de crescimento indeterminado, conduzido com uma haste por planta e com espaçamento de l,0m entre fileiras e 30cm entre plantas. Para avaliar a fertilidade do solo no interior das estufas de 40 municípios mais representativos da plasticultura da região, amostras de solo foram retiradas a 5cm da base da planta, nas profundidades de 0-10cm e 10-20cm e, posteriormente determinou-se os teores de P, K, Ca, Mg, Al, %M.O., teor de argila e pH em água. O ajuste matemático do rendimento de frutos do tomateiro em função das doses de adubação, na análise conjunta dos experimentos, permitiu a obtenção do ponto de máxima eficiência técnica situado em 2,87 vezes a recomendação de adubação. Constatou-se que a média do pH no interior das estufas amostradas em 40 municípios, foi inferior a 5,5, nas profundidades de 0-10cm e 10-20cm.. Os teores médios de P, K, Ca e Mg, nas duas profundidades, situaram-se na classe de disponibilidade alta.An experiment under plastic greenhouse was carried out to evaluate tomato productivity in response to mineral fertilization and also to evaluate the soil fertility in greenhouse of 40 counties. The treatments tested were: 0, 1, 3 and 5 times the amount of currently recommended fertilizer. The experiment was conductedon a Hapludalf soil

  14. 基于单片机的大棚温湿度控制系统设计%SCM-based Temperature and Humidity Control System for Vegetable Greenhouse

    Institute of Scientific and Technical Information of China (English)

    易顺明; 赵海兰; 袁然

    2011-01-01

    An intelligent temperature/humidity control system was designed for vegetable greenhouses based on computer automatic control. The design thought of the system softwares and hardwares such as temperature/humidity acquisition system, temperature/humidity display, control system and heater control circuit are expoundcd. Taking DS18820 and HM1500LF as the temperature/humidity sensors , single chip microcomputer AT89S52 as a core of the system , the simulation of the system was performed with DELPHI software. The result shows that the intelligent temperature/humidity control system designed in the research has good human-computer interface, simple and convenient operation, high automation degree,low cost and good application foreground.%针对研究蔬菜大棚智能温湿度控制,设计了一种基于计算机自动控制的智能蔬菜大棚温湿度控制系统.详细阐述了该系统的温湿度采集、温湿度显示、控制系统等系统软硬件的设计思想,以DSl8820和HMl500LF作为温湿度传感器,以AT89S52单片机为系统核心,最后利用DELPHI软件进行系统仿真.该研究设计的蔬菜大棚智能温湿度控制系统人机界面良好,操作简单方便,自动化程度高,造价低廉,具有良好的应用前景和推广价值.

  15. [Greenhouse gases fluxes of biological soil crusts and soil ecosystem in the artificial sand-fixing vegetation region in Shapotou area].

    Science.gov (United States)

    Hu, Yi-Gang; Feng, Yu-Lan; Zhang, Zhi-Shan; Huang, Lei; Zhang, Peng; Xu, Bing-Xin

    2014-01-01

    Uncertainties still existed for evaluating greenhouse gases fluxes (GHGs), including carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) at the regional scale for desert ecosystem because available GHGs data about biological soil crusts (BSCs) was very scarce. In 2011 and 2012, soil ecosystem covered by various types of BSCs and BSCs at different succession stages in an artificial sand-fixing vegetation region established in various periods at southeast of the Shapotou area in Tengger Desert was selected to measure fluxes of CO2, CH4 and N2O using static chamber and gas chromatography. The results showed that curst type, recovery time and their interactions with sampling date significantly affected CO2 flux. Recovery time and interaction of crust type and sampling date significantly affected CH4 flux. Sampling date significantly affected the fluxes of CO2, CH4 and N2O. The mean annual flux of CO2 for moss crust (105.1 mg x m(-2) x h(-1)) was significantly higher than that of algae crust (37.7 mg x m(-2) x h(-1)) at the same succession stage. Annual mean CH4 and N2O consumption was 19.9 and 3.4 microg x m(-2) x h(-1), respectively. Mean annual consumption of CH4 and N2O for algae crust was slightly higher than that of moss crust, however, significant difference was not found. Ecosystem respiration (Re) of desert soil covered by BSCs increased with the recovery process of desert ecosystem, in contrast, consumption of CH4 and N2O decreased. Re of moss crust was more sensitive to temperature and moisture variation than algae crust and Re sensitivity of temperature and moisture gradually increased with the development and succession of BSCs. Both soil temperature and moisture were not the main factor to determine CH4 and N2O fluxes of BSCs-soil in desert ecosystem.

  16. Design of Aeroponics Greenhouse Vegetable Harvester Harvesting Machanism%温室雾培蔬菜收获机收获机构的研究设计

    Institute of Scientific and Technical Information of China (English)

    高国华; 王天宝

    2015-01-01

    雾培种植具有节约空间、增大产量等特点,是一种新型的种植模式,代表了未来农业种植的方向。为此,针对雾培蔬菜收获劳动强度高、收获效率低等问题,创新性地对温室雾培蔬菜收获机中收获机构进行系统性设计,达到对雾培蔬菜快速稳定收获切根的目的要求。依据人工收获流程及定植板的实际特征,利用 SolidWorks对蔬菜收获机构进行方案设计,在设计过程中参考了成熟的工程案例,选取合适的切根方法和刀具结构,减少了切削方式及振源振动对收获切根的影响。运用SolidWorks Motion 对收获机构中的切根机构的运动稳定性进行验证,证明了切根机构在工作过程中可以稳定运行,保持稳定的加速度。利用 ANSYS 对收获机构中的夹取手爪和切根手爪进行有限元分析,确保关键结构的强度和刚度达到工程技术要求,有效地减少了生产资源的浪费,同时缩短了结构设计的时间,并为样机制作提供了坚实的基础。%Aeroponics planting has the characteristics of space-efficient, high productivity and so on , which is the new cultivation way in the future and represents the future direction of agricultural cultivation .In this paper , a planting aero-ponics greenhouse vegetable harvester which achieve the purpose of rapid and steady harvest aeroponics cut root vegeta -bles requirements is designed innovatively , aiming at the shortage of high labor strength and low harvest efficiency in the traditional harvesters .Through the analysis of manual harvesting process as well as the actual characteristics of vegetables and planting board , the vegetable harvest mechanism is designed by SolidWorks .In the design process , it refer to the mature project cases as well as select the appropriate method and tool cutting root structure , the cutting mode and vibra-tion sources for harvesting root effect has reduced .In addition , the

  17. Prediction and analysis model of temperature and its application to a natural ventilation multi-span plastic greenhouse equipped with insect-proof screen

    Institute of Scientific and Technical Information of China (English)

    LIU Shu-zhen; HE Yong; ZHANG Yu-bao; MIAO Xiang-wen

    2005-01-01

    The natural ventilation widely used in greenhouses has advantages of saving energy and reducing expense. In order to provide information for climate control of greenhouse, a model was developed to predict the variation of air temperature in the naturally ventilated greenhouse equipped with insect-proof screen. Roof ventilation and combined roof and sidewall ventilation were considered in the model. This model was validated against the results of experiments conducted in the greenhouse when the wind was parallel to the gutters. The model parameters were determined by the least squares method. In the used model, effects of wind speed and window opening height on the air temperature variation were analyzed. Comparison between two types of ventilation showed that there existed a necessary ventilation rate which results in air temperature decrease in natural ventilation under special climatic conditions. In our experiments when wind speed was less than 3.2ms-1, wind had a more gradual effect on greenhouse temperature for roof ventilation, compared with combined roof and sidewall ventilation, which had greater air temperature decrease than roof ventilation only.

  18. Danos físicos em estufas plásticas causados pelo vento em Santa Maria, RS Plastic greenhouses damaged by wind in Santa Maria, RS. Case report

    Directory of Open Access Journals (Sweden)

    Nereu Augusto Streck

    1998-03-01

    Full Text Available Foram observados danos físicos causados por rajadas de vento ocorridos na madrugada do dia 19/05/97 no plástico das estufas localizadas no Campus da Universidade Federal de Santa Maria. Os valores de intensidade e direção das rajadas máximas do vento foram registradas em um anemográfo universal tipo IH 1023 a 10m de altura, instalado a aproximadamente 100m ao sul das estufas. Os danos ocorreram quando a velocidade das rajadas máximas ultrapassou 20m s-1 (72km h-1Plastic greenhouses located at the Federal University of Santa Maria, Rio Grande do Sul State, Brazil were damaged by wind on May 19th, 1997. Wind speed and direction at 10m height were measured at the Climatological Station located approximatly 100m from the greenhouses. The damage in the greenhouses occured when the maximum gusts reached up speed higher than 20m s-1 (72km h-1.

  19. Design of fuzzy-neural network control system for northern vegeta-bles greenhouse%北方蔬菜温室系统模糊神经网络控制器的设计

    Institute of Scientific and Technical Information of China (English)

    孙丽萍; 霍然

    2014-01-01

    Whether vegetable greenhouse system can make an accurate reaction on time for the change of environmental factors determine the survival rate and the growth cycle of the vegetables. Therefore, to improve the control rate, control accuracy of the greenhouse system has great realistic significance for the practicability of greenhouse system. This article mainly aimed to traditional cucumber greenhouse system has lots of shortages as large overshoot, low accuracy and so on. Combine fuzzy control with neural network, designed fuzzy-neural network control system, presented the rules of the reasoning, given the corresponding learning algorithm, then proved by simulation that fuzzy-neural network system had high reasoning speed and good robustness, meets the system requirement.%蔬菜温室系统对环境因素的变化能否及时做出精确反应,决定蔬菜的成活率、生长周期。因此,提高温室系统的控制速率、控制精度对提高温室系统实用性具有现实意义。文中针对传统黄瓜温室系统超调大,精度低等缺点,提出模糊控制与神经网络相结合的方法,设计模糊神经网络控制器。建立模糊推理规则,给出相应的学习算法,并对控制结果进行软件仿真和试验验证。其结果证明该控制器具备推理速度快、鲁棒性好等优点,可弥补传统控制器的不足。

  20. 磁力轮式塑料大棚清洗装置的设计与试验%Design and experiment of cleaning device with magnetic wheels for plastic greenhouses

    Institute of Scientific and Technical Information of China (English)

    何培祥; 汪洋; 何家成; 梁永江

    2015-01-01

    The technology of plastic greenhouses is widely used in China. Greenhouses’ films get dirty easily with dusts and mosses with the increasing of use time. That’s the reason why its transmittance (which is one of the important factors that affect the greenhouses’ productivity) decreases. Nowadays, cleaning devices are mainly designed for glass curtain walls, ventilating ducts and air conditioner pipes. These cleaning devices have difficulties in cleaning plastic greenhouses because of the greenhouses’ arc frames and the films’ variable surfaces. To solve the problems, a cleaning device with magnetic wheels was designed in this paper. The cleaning device consists of magnetic wheel walking mechanism and brush cleaning mechanism, whose core components are magnetic wheels, walking motors, brushes and cleaning motors. When greenhouses need cleaning, put the device on the greenhouses’ canopy and provide power for it. Thus, the walking motors can drive the magnetic wheels to walk forward on the greenhouses’ frame by magnetic absorption. Meanwhile, the cleaning motors also drive the brushes to clean the greenhouses with water or detergent for the first time. When the device walks to the top of the canopy, manually shift the power switch to make walking motors rotate reversely, then, the device can walk back and operate the second cleaning work. When the device returns to the bottom of the greenhouses’ frame, it should be translated to the neighboring frame for the next cleaning work. The device’s minimum driving force and magnetic force were calculated by the device’s mechanical model and its force situation analysis, which was essential for walking on the greenhouses’ frames. The analysis results showed that the driving force and magnetic force needed at least 58.9 and 235.6 N, respectively. And each magnetic wheel’s magnetic force was no less than 58.9 N. In order to verify whether the magnetic wheel met the requirements of minimum magnetic force

  1. Vegetation as self-adaptive coastal protection: Reduction of current velocity and morphologic plasticity of a brackish marsh pioneer.

    Science.gov (United States)

    Carus, Jana; Paul, Maike; Schröder, Boris

    2016-03-01

    By reducing current velocity, tidal marsh vegetation can diminish storm surges and storm waves. Conversely, currents often exert high mechanical stresses onto the plants and hence affect vegetation structure and plant characteristics. In our study, we aim at analysing this interaction from both angles. On the one hand, we quantify the reduction of current velocity by Bolboschoenus maritimus, and on the other hand, we identify functional traits of B. maritimus' ramets along environmental gradients. Our results show that tidal marsh vegetation is able to buffer a large proportion of the flow velocity at currents under normal conditions. Cross-shore current velocity decreased with distance from the marsh edge and was reduced by more than 50% after 15 m of vegetation. We were furthermore able to show that plants growing at the marsh edge had a significantly larger diameter than plants from inside the vegetation. We found a positive correlation between plant thickness and cross-shore current which could provide an adaptive value in habitats with high mechanical stress. With the adapted morphology of plants growing at the highly exposed marsh edge, the entire vegetation belt is able to better resist the mechanical stress of high current velocities. This self-adaptive effect thus increases the ability of B. maritimus to grow and persist in the pioneer zone and may hence better contribute to ecosystem-based coastal protection by reducing current velocity.

  2. Research Progress in the Phthalate Acid Esters (PAEs) Pollution and Remediation in the Soil of Vegetable Greenhouses in China%我国设施菜地邻苯二甲酸酯污染现状及防治研究进展

    Institute of Scientific and Technical Information of China (English)

    何丽芝; 陆扣萍; 秦华; 王海龙

    2012-01-01

    综述了我国设施菜地土壤邻苯二甲酸酯类化合物的污染现状及其防治方法,并对未来的研究方向进行了展望.分析表明,我国设施菜地土壤已受到不同程度的污染,对其治理迫在眉睫;不同种类的PAEs在土壤中的分布具有空间和时间规律;设施菜地土壤PAEs主要污染来源为大棚和地膜、污灌、肥料等途径:目前PAEs污染土壤主要通过在土壤中添加堆肥、污泥以及接种降解菌株等方法治理.%The paper reviewed the phthalate acid esters ( PAEs) pollution and remediation methods, and then forecasted its future research direction. As indicated by the analytic results, the vegetation greenhouse soils in China are contaminated to different degrees, and in urgent need for treatment; the different types of PAEs in soils presented spatial and temporal distribution rules; plastic roofing materials, mulching film, and fertilizers are the potential sources of PAEs in greenhouse soils; the PAEs contaminated soils are mainly remediated through the application of compost and bio-solids, and the inoculation with selected PAEs degrading microorganisms.

  3. Greener greenhouses

    Energy Technology Data Exchange (ETDEWEB)

    Paksoy, Halime; Turgut, Bekir; Beyhan, Beyza; Dasgan, H. Yildiz; Evliya, Hunay; Abak, Kazim; Bozdag, Saziye

    2010-09-15

    Agricultural greenhouses are solution to the increased demand for higher production yields, facilitating off season cultivation and allowing the growth of certain varieties in areas where it was not possible earlier. Heating and/or cooling system, required to maintain the inside micro-climate in greenhouses mostly rely on fossil fuels and/or electricity. This paper aims to discuss the 'greener' solutions for heating and cooling systems of greenhouses based on different thermal energy storage concepts. Results from a greenhouse Aquifer Thermal Energy Storage (ATES) application in Turkey producing tomatoes with zero fossil fuels and up to 40% higher yield are presented.

  4. Design of Step Motor Controller for Rolling Door and Ventilator of Vegetable Greenhouse%蔬菜大棚卷帘门和换气扇步进电机智能控制器的设计

    Institute of Scientific and Technical Information of China (English)

    张飞云

    2013-01-01

    为实现蔬菜大棚温湿度的智能控制,以AT89S52单片机为控制核心,35BYJ46步进电机为控制对象,采用ULN2003A驱动芯片实现对步进电机的转速及定位控制,根据实时采集的温湿度数据,通过控制卷帘门的开度及换气扇的转速,从而调节蔬菜大棚的温湿度.同时,通过M35模块(GPRS)和红外模块可以实现控制系统的远程控制和近程控制.%In order to realize the intelligent control of the temperature and humidity about vegetable greenhouse,AT89S52 single chip microcontroller was taken as the control core to control step motor 35BYJ46,ULN2003A was used to realize speed and positioning control of step motor,according to the real-time acquisition of the temperature and humidity data,through controlling the shutters opening and the speed of ventilator,the temperature and humidity of the vegetable greenhouse was adjusted.At the same time,it could realize remote and short range control through the M35 module (GPRS) and infrared module.

  5. Mist greenhouse

    NARCIS (Netherlands)

    Weel, van P.A.; Voogt, J.O.

    2007-01-01

    The present invention relates to a greenhouse system with a climate regulation which is controlled through measuring the stomatal aperture of the plants present in the greenhouse. The regulation mainly consists of controlling a misting installation and optionally of adjusting other, conventional

  6. (AJST) EFFECTS OF GROUND INSULATION AND GREENHOUSE ...

    African Journals Online (AJOL)

    NORBERT OPIYO AKECH

    of plastic digester to produce biogas under natural and greenhouse microenvironment. The specific ... and hydrogen sulphide (H2S). Biogas ... the effect of ground insulation on biogas production. ..... Methane Generation from Human, Animal.

  7. Application of Frequency Vibration Type Insecticidal Lamp in the Production of Greenhouse Vegetable in Xichang%频振式杀虫灯在西昌市大棚蔬菜生产上的应用

    Institute of Scientific and Technical Information of China (English)

    王云梅; 罗晓玲; 杨馨; 付立会; 黄修芬

    2015-01-01

    Frequency trembler lamps in 4 greenhouse vegetable demonstration sites were killing 7 orders and 17 families 23 species, including 21 species of pests. The main pests have insecticidal effects harmful to vegetable, especially for lepidoptera pest control effect was significant. The results of the application show that the hanging area is higher than that of no light district of Spodoptera litura and beet armyworm larvae weight were reduced 84.10%, 74.49%, while reducing drug times, decreasing the cost of drug use, ensuring the safety of vegetables, pollution-free production, popularization and application in large area.%频振式杀虫灯在4个大棚蔬菜示范点共诱杀7目17科23种昆虫,其中害虫21种,对危害蔬菜的主要害虫均有诱杀作用,特别对鳞翅目害虫防效显著.应用结果表明:挂灯区比无灯区斜纹夜蛾和甜菜夜蛾幼虫量分别降低84.10%、74.49%,同时减少用药次数,节约用药成本,保证蔬菜安全、无公害生产,可大面积推广应用.

  8. 日光温室蔬菜根结线虫病综合防治技术%Vegetable Root Knot Nematode Disease Integrated Control Technology in Solar Greenhouse

    Institute of Scientific and Technical Information of China (English)

    王小云; 刘珍

    2016-01-01

    根结线虫病作为毁灭性蔬菜病害之一,在银川市日光温室蔓延发生。笔者分析了该病的发生规律、发病条件,并从农业防治、生物防治、化学防治等方面阐述了综合防治措施。%Root knot nematode disease, one of deadly vegetable diseases, occurs in solar greenhouses in Yinchuan. Root knot nematode disease occurrence regularity and condition were analyzed in this paper, along with integrated control technology in aspects of agricultural, biological and chemical control.

  9. Accounting for co-products in energy use, greenhouse gas emission savings and land use of biodiesel production from vegetable oils

    NARCIS (Netherlands)

    Corré, W.J.; Conijn, J.G.; Meesters, K.P.H.; Bos, H.L.

    2016-01-01

    Accounting for co-products of vegetable oil production is essential in reviewing the sustainability of biodiesel production, especially since oil crops produce valuable protein-rich co-products in different quantities and qualities. Two accounting methods, allocation on the basis of energy conten

  10. Estimation model for daily transpiration of greenhouse muskmelon in its vegetative growth period%温室甜瓜营养生长期日蒸腾量估算模型

    Institute of Scientific and Technical Information of China (English)

    张大龙; 李建明; 吴普特; 李玮黎; 赵志华; 徐菲; 李俊

    2013-01-01

    建立了基于温室环境参数、甜瓜生长发育参数和土壤水分参数的温室甜瓜日蒸腾量估算模型,以研究温室条件下甜瓜蒸腾量的估算方法.根据温室内特定环境对PenmanMonteith方程中空气动力项进行修正,推导出了适于计算温室条件下参考作物蒸腾量的温室环境因子子模型;以甜瓜叶面积指数为自变量构建了作物因子子模型,模型形式为线性函数;以土壤相对有效含水量为自变量构建了土壤水分因子子模型,模型形式为对数函数.采用分期播种法,根据周年不同播期实测数据对模型参数进行估计和分析.采用土壤相对含水量分别为80%、70%、60%的实测蒸腾数据,对模型在充分灌溉和节水灌溉条件下的预测精度进行了检验,模拟值的平均相对误差分别为11.5%、16.2%、16.9%.所建蒸腾模型是对PenmanMonteith公式在温室环境和节水灌溉条件下的有益探索,具有重要推广应用价值.%For developing an estimation method of muskmelon transpiration in greenhouse,an estimation model for the daily transpiration of greenhouse muskmelon in its vegetative growth period was established,based on the greenhouse environmental parameters,muskmelon growth and development parameters,and soil moisture parameters.According to the specific environment in greenhouse,the item of aerodynamics in Penman-Monteith equation was modified,and the greenhouse environmental sub-model suitable for calculating the reference crop evapotranspiration in greenhouse was deduced.The crop factor sub-model was established with the leaf area index as independent variable,and the form of the model was linear function.The soil moisture sub-model was established with the soil relative effective moisture content as independent variable,and the form of the model was logarithmic function.With interval sowing,the model parameters were estimated and analyzed,according to the measurement data of different sowing

  11. 南方塑料大棚冬春季温湿度的神经网络模拟%Neural Network Simulation on Air Temperature and Relative Humidity inside Plastic Greenhouse during Winter and Spring in Southern China

    Institute of Scientific and Technical Information of China (English)

    李倩; 申双和; 曹雯; 邹学智

    2012-01-01

    Based on the meteorological data both inside and outside the plastic greenhouse in Cixi, Zhejiang province and agricultural meteorological experimental station of Nanjing University of Information Science and Technology, three BP neural network models were established, which the input variable was chosen as radiation solar outdoor, air temperature, relative humidity and wind speed, and output variable was chosen as temperature indoor and relative humidity. The results showed that all of the root mean square error (RMSE) between trained air temperature and measured value from three models was no more than 2℃ and the relative error (RE) no more than 4% respectively. Both RMSE and RE between trained relative humidity and measured value was no more than 7 percent points and 7% . All of the RMSE between predicted air temperature and measured value from three models was 2℃ approximately, and their RE was no more than 6% in spring, less than that in winter. RMSE and RE predicated relative humidity and measured value was no more than 7 percent points and 9% respectively. The results indicated that three BP neural network models had quite precisely for predicting temperature indoor and relative humidity in plastic greenhouse, which could meet the forecast requirements for plastic greenhouse microclimate.%利用浙江省慈溪市草莓塑料大棚和南京信息工程大学农业气象试验站番茄塑料大棚的小气候观测数据及气象站资料,建立3个以棚外辐射、温度、相对湿度和风速为输入变量,棚内温度和相对湿度为输出变量的BP神经网络预测模型.结果表明,3个模型气温训练值与实测值的均方根误差(RMSE)都在2℃以内,相对误差都在4%左右;相对湿度训练值的RMSE都在7个百分点以内,相对误差不超过7%.利用此模型得到的气温预测值与实测值的RMSE都在2℃左右,冬季气温的相对误差较大,春季通风和不通风模型气温的相对误差不超过6%;

  12. Modelo de simulação da temperatura e umidade relativa do ar no interior de estufa plástica Simulation model of air temperature and relative humidity in to plastic greenhouses

    Directory of Open Access Journals (Sweden)

    Edilson Costa

    2004-04-01

    Full Text Available A simulação dos parâmetros climáticos de temperatura e umidade relativa do ar no interior de uma estufa plástica, por meio do balanço de energia, pode propiciar ao produtor uma ferramenta de auxílio na tomada de decisão. Nesse propósito, realizou-se uma simulação das condições no interior de estufa plástica, em função de parâmetros externos e internos a ela. A simulação revelou uma temperatura no interior da estufa plástica de 23,6 ºC, e os sensores revelaram um valor médio de 24,1 ºC para o período de cultivo da alface. Para a umidade relativa no interior da estufa plástica, o valor simulado foi de 61,6%, e o obtido com o auxílio de sensores foi de 66,0%. Os valores simulados apresentaram-se próximos dos valores obtidos pelos sensores, mostrando que o modelo pode ser usado para a estimativa da temperatura e umidade relativa do ar no interior da estufa plástica.Simulation of climatic parameters inside air temperature and relative humidity of plastic greenhouse, trough energy balance, allows to growers a good technical tool on the decision making to improve the performance of inside environments. A simulation of internal conditions based on external and internal parameters was evaluated. The results showed the inside mean temperature of 23.6 ºC in comparison with the experimental value of 24.1 ºC, for the cultivated period. The simulated relative humidity presented a value of 61.6% against 66.0% obtained by the sensors. The simulated values were closed to the values obtained by the sensors, which means that the model can be used to determine the internal conditions of plastic greenhouses.

  13. A geographical assessment of vegetation carbon stocks and greenhouse gas emissions on potential microalgae-based biofuel facilities in the United States.

    Science.gov (United States)

    Quiroz Arita, Carlos; Yilmaz, Özge; Barlak, Semin; Catton, Kimberly B; Quinn, Jason C; Bradley, Thomas H

    2016-12-01

    The microalgae biofuels life cycle assessments (LCA) present in the literature have excluded the effects of direct land use change (DLUC) from facility construction under the assumption that DLUC effects are negligible. This study seeks to model the greenhouse gas (GHG) emissions of microalgae biofuels including DLUC by quantifying the CO2 equivalence of carbon released to the atmosphere through the construction of microalgae facilities. The locations and types of biomass and Soil Organic Carbon that are disturbed through microalgae cultivation facility construction are quantified using geographical models of microalgae productivity potential including consideration of land availability. The results of this study demonstrate that previous LCA of microalgae to biofuel processes have overestimated GHG benefits of microalgae-based biofuels production by failing to include the effect of DLUC. Previous estimations of microalgae biofuel production potential have correspondingly overestimated the volume of biofuels that can be produced in compliance with U.S. environmental goals. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Desarrollo vegetativo de patrones cítricos cultivados en condiciones de invernadero bajo dos sistemas de riego Vegetative development of citrus seedlings cultivated at greenhouse conditions and submitted to two irrigations systems

    Directory of Open Access Journals (Sweden)

    Gilmar Schäfer

    2006-08-01

    Full Text Available En el presente estudio se evaluó el desarrollo vegetativo de patrones cítricos cultivados en invernadero bajo dos sistemas de riego. El experimento se realizó en la Estação Experimental Agronômica de la Universidade Federal do Rio Grande do Sul, ubicada en Eldorado do Sul, Rio Grande do Sul, Brasil, entre los meses de septiembre de 2003 y abril de 2004, totalizando 225 días de experimentación. El diseño experimental fue de parcelas subdivididas, en factorial 2 x 3, con 4 repeticiones de 22 contenedores cada. En las parcelas principales se evaluaron los sistemas de riego (microaspersión y capilaridad y en las subparcelas los patrones cítricos Poncirus trifoliata (L. Raf., citrangero 'C37' [P. trifoliata x Citrus sinensis (L. Osb. cv. Pêra] y lima 'Rangpur' (C. limonia Osb.. En condiciones de invernadero los patrones cítricos presentan un desarrollo vegetativo más rápido bajo riego por capilaridad respecto a la microaspersión. Los patrones cítricos evaluados presentan desarrollos vegetativos distintos, donde el citrangero 'C37' supera a los demás.The aim of the present work was to evaluate the vegetative development of citrus rootstock seedlings cultivated under greenhouse conditions with two irrigation systems. The experiment was conducted at the Estação Experimental Agronômica , Universidade Federal do Rio Grande do Sul, located in Eldorado do Sul, Rio Grande do Sul, Brazil, from September 2003 to April 2004, totalizing 225 days of experimentation. The experimental design was a split-plot, in a 2x3 factorial, with 4 replications of 22 pots each. In the main plot the irrigation systems was evaluated (micro sprinkler and capillarity and in the split-plot the citrus rootstocks [Trifoliate orange - Poncirus trifoliata (L. Raf., 'C37' citrange - P. trifoliata x Citrus sinensis (L. Osb. cv. Pêra and 'Rangpur' lime - C. limonia Osb.] were evaluated. The main result showed in conditions of greenhouse citrus rootstock seedlings

  15. Comportamento vegetativo e produtivo de videiras 'Cabernet sauvignon' cultivadas sob cobertura plástica Vegetative growth and yield of 'Cabernet sauvignon' grapevine under overhead plastic covering

    Directory of Open Access Journals (Sweden)

    Clenilso Sehnen Mota

    2008-03-01

    randomized block design, with two treatments (uncovered and covered plants and four replicates of 15 plants (experimental unit. The micro-environmental changes imposed by the cover did not affect grapevines phenology. The grapevines under the cover had higher values for branches growth (length and fresh mass, and leaf expansion (area and dry mass than the uncovered ones. The berries weight and diameter were superior on grapevines under covering plastic only at earlier stages of fruit growth but not at harvest. The other variables assessed were not affected by the cover. The results show that overhead plastic covering can interfere with vegetative growth without affecting yield.

  16. Pilot Greenhouse

    CERN Multimedia

    1983-01-01

    This pilot greenhouse was built in collaboration with the "Association des Maraichers" of Geneva in the frame of the study for making use of the heat rejected as warm water by CERN accelerators and experiments. Among other improvements, more automated and precise regulation systems for heating and ventilation were developed. See also 8305598X.

  17. Urban Options Solar Greenhouse Demonstration Project. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Cipparone, L.

    1980-10-15

    The following are included: the design process, construction, thermal performance, horticulture, educational activities, and future plans. Included in appendices are: greenhouse blueprints, insulating curtain details, workshop schedules, sample data forms, summary of performance calculations on the Urban Options Solar Greenhouse, data on vegetable production, publications, news articles on th Solar Greenhouse Project, and the financial statement. (MHR)

  18. Design of Distributed Multi-point Temperature Monitoring System in Vegetable Greenhouses%蔬菜大棚分布式多点温度监控系统的设计

    Institute of Scientific and Technical Information of China (English)

    冯荣华; 王强; 叶大鹏; 谢艺鑫

    2016-01-01

    Considering problems of low management efficiency and high administration cost in vegetable greenhouse, a distribu-ted multi-point temperature intelligent monitoring system was designed.This system could realize the goal of multi-point and comprehensive information acquisition, automatic alarm when temperature runs above the threshold or in low voltage state by combi-ning the wireless communication technology with the sensor and upper monitor technology .The result shows that this system is suit-able for the environment parameters monitoring in greenhouse with the features of stable operation, strong real-time performance and high inspection accuracy (97.55%) .%针对蔬菜大棚的管理效率低、管理费用高等问题,设计了分布式多点温度智能监控系统。本系统有效结合无线通信技术、传感器技术、上位机技术,实现了蔬菜大棚温度参数进行多点全方位采集,且具有温度超过阈值、电压不足时自动报警的功能。经过实验表明,该系统工作稳定、监测实时性强、检测精度高(可达到97.55%),可适用于蔬菜大棚中的环境参数监测。

  19. Design of Environment Monitoring System in Multi-span Vegetable Greenhouse Based on Internet of Things%基于物联网的连栋蔬菜温棚环境监测系统设计

    Institute of Scientific and Technical Information of China (English)

    刘渊; 王瑞智; 杨泽林

    2014-01-01

    For high costs , rough control and complex wiring of traditional multi-span vegetable greenhouse monitoring system , a precision agriculture information perception system was designed based on the characteristics of accurate per -ception , efficient transmission and intelligent monitoring of Internet of Things .The system consisted of the Wireless Sensor Networks , transmission node , GPRS wireless transmission network , and PC management .C8051 F410 microcontroller , as the control core of monitoring nodes in greenhouse , communicated through the Wireless Sensor Networks .WEB server , which was the platform of host computer , managed data combined with MS SQL Server database .Real-time environment information for crop growth could be obtained by the system and then be transmitted to host computer management sys -tem.The corresponding feedback would be regulated through the expert discrimination system .Experiment showes that , the system monitors a variety of environmental parameters in greenhouse effectively and meets the actual agricultural pro -duction requirements .%针对传统连栋温棚监测系统存在的成本较高、控制粗略、布线复杂等问题,设计了一种精准农业信息感知系统。系统基于物联网的精确感知、高效传输以及智能监控的特点,由无线感知网络、传输节点、GPRS 无线传输网络和上位机管理等多个部分组成。温棚中的监测节点以C8051F410单片机为控制核心,通过无线传感网络进行通信,上位机以 WEB 服务器为平台,结合MS SQL Server 数据库对数据管理。系统能够实时感知作物生长环境信息,并将参数传输到上位机管理系统,经专家系统判别后进行相应反馈调控。实验证明,系统可以对温室内的多种环境参数进行有效的监测,满足实际农业生产要求。

  20. 基于Malthus模型的温室蔬菜杀虫剂合理使用方案%The Reasonable Use Program for Greenhouse Vegetables Insecticides in View of MALTHUS Model

    Institute of Scientific and Technical Information of China (English)

    段克峰

    2011-01-01

    [Objective] The aim was to study reasonable use program for greenhouse vegetables insecticides. [Method] By applying the relating knowledge on differential equation and mathematical analysis based on Malthus mathematical model, a economical and effective insecticides use model was established . [ Result ] To simplify the model, multiplex linear programming problem of aperiodic multiple usage pesticide was changed into two binary nonlinear programming problem of periodically using pesticide, such that the model solution could be carried out directly by mathematical software. [Conclusion] The mode had popularization using value.%[目的]研究温室蔬菜杀虫剂合理使用方案.[方法]基于Malthus教学模型,运用微分方程和数学分析的有关知识建立了一种经济有效的杀虫剂使用模型.[结果]为了简化模型,将所得到的不定期多次使用杀虫药的多元非线性规划问题转化成周期性使用杀虫药的2个二元非线性规划问题,使模型求解可以直接采用数学软件来实现.[结论]该模型具有较强的推广应用价值.

  1. Effects of Different Film Mulching Cultivations on Growth and Yield of Vegetable in Greenhouse%大棚不同地膜栽培对蔬菜生长及产量的影响

    Institute of Scientific and Technical Information of China (English)

    汪红武; 熊常财; 蔡克桐; 李景株; 彭涛; 汤涤洛

    2014-01-01

    By using different film mulching metnods, we studied the effects of bast fiber film mulching cultivation on growth and yield of pepper and cucumber in greenhouse. The results showed that, the bast fiber film mulching cultivation could promote vegetable growth, improve the pepper and cucumber yield. Under the bast fiber film mulching cultivation, pepper and cucumber yield increased by 5.2%and 14.5%than those of black polyethylene film mulching cultivation, and significantly increased by 24.7%and 23.0%than those of the control (no film mulching).%通过在大棚内进行不同地膜,研究了大棚内麻地膜覆盖对辣椒、黄瓜生长及产量的影响。试验结果表明,大棚内麻地膜覆盖栽培促进蔬菜生长,提高辣椒、黄瓜产量。麻地膜覆盖栽培辣椒、黄瓜比聚乙烯农用黑膜增产5.2%、14.5%,比CK(不覆盖)增产24.7%、23.0%,与对照相比均达到显著差异。

  2. Biological control of whitefly on greenhouse tomato in Colombia: Encarsia formosa or Amitus fuscipennis?

    NARCIS (Netherlands)

    Vis, de R.J.

    2001-01-01

    In Colombia, biological control of pests in greenhouse crops is only applied on a very limited scale in ornamentals and as yet non-existent in greenhouse vegetables. Greenhouse production of vegetables - mostly tomatoes- is a recent development, as a result of the high losses of field production due

  3. 保护地蔬菜土壤中木霉菌种群影响因素%Effect Factors to Trichoderma Populations in Greenhouse Soil of Vegetables

    Institute of Scientific and Technical Information of China (English)

    贺字典; 高玉峰; 吴贺平; 高增贵; 张洋

    2011-01-01

    采用传统的形态学特征和ITS、TEF序列比对鉴定出11个木霉种,其中长枝木霉Trichoderma longibrachiatum、深绿木霉Trichoderma atroviride和哈茨木霉Trichoderma harzianum是蔬菜保护地土壤中的优势种群.同时研究表明种植年限、蔬菜种类、轮作制度、杀菌剂等均会影响木霉菌数量和分布,木霉菌的数量与种植年限、蔬菜种植结构密切相关,连作时,当种植年限超过10 a,木霉菌数量减少;轮作地比连作地木霉菌数量虽然下降,但在真菌中的比例却呈上升趋势;种植葱蒜类蔬菜的地块比种植番茄、黄瓜的地块木霉菌数量多.从蔬菜田中分离到的木霉菌对杀菌剂的抗性较强.土壤因素中以土壤有机质含量对木霉菌数量的影响最为重要,达到极显著水平,回归直线方程为y=0.13x-1.07.表明提高土壤中有机质含量及轮作是提高木霉菌生物种群多样性的主要因子.%Using traditional morphological classification and ITS, TEF sequences analysis methods,eleven Trichoderma species were identified and as three of which, T. longibrachiatum, T. atroviride, and T. harzianum, were dominant species. At the same time, quantities and distribution of Trichoderma in soils were affected by cultivating ages, vegetable species, fungicides and rotation pattern etc. The result showed that quantities of Trichoderma were closely related to cultivating ages and rotation pattern. (i) Continuous cropping exceeding 10 years decreased the quantities of Trichoderma. And rotation also decreased the quantities of Trichoderma, but its percentage in the fungi groups were increasing. (ii) Trichoderma quantities in the rhizosphere of allium vegetables were more than in the rhizosphere of tomato and cucumber. (iii) The resistance of Trichoderma to fungicides was stronger than those from other environments. (iv)The effect of organic nutrition on Trichoderna quantities was the most important in the soils factors and linear

  4. Control effect of five biological agents on vegetable root-knot nematodes in greenhouse%5种生物制剂对设施蔬菜根结线虫防治技术研究

    Institute of Scientific and Technical Information of China (English)

    席先梅; 白全江; 张庆萍; 李玉民; 贺小勇; 孔庆全; 魏海明; 赵存虎

    2015-01-01

    蔬菜根结线虫已成为内蒙古赤峰市设施蔬菜园区的主要病害,对黄瓜和番茄造成严重的产量损失,为了筛选高效、安全的生物杀菌剂,2011-2012年在赤峰市松山区设施蔬菜园区进行了5种不同生物杀菌剂对设施黄瓜和番茄根结线虫防治的田间试验,在黄瓜和番茄定植时用100亿 cfu/g 厚孢轮枝菌粉剂0.2 kg/667 m2撒施,2%阿维菌素+多聚糖乳油3000倍稀释液灌根处理,0.2亿 cfu/g 淡紫拟青霉颗粒剂5 kg/667 m2撒施,10亿 cfu/mL 蜡质芽胞杆菌水剂6 L/667 m2灌根,1.8%阿维菌素乳油500倍稀释液灌根,设4次重复,并设空白对照。定植20 d 后再用同样的浓度和方法处理一次,结果表明:5种生物杀菌剂对黄瓜和番茄根结线虫的防治效果为20%~60%,10亿cfu/mL 蜡质芽胞杆菌水剂效果最好,达到56.3%,同时可以提高黄瓜和番茄的商品性,适于在设施蔬菜上推广使用。%Root-knot nematode has become the major threat for greenhouse vegetable production in Chifeng City of Inner Mongolia,and caused serious yield losses on cucumber and tomato.The field experiment was conducted to determine the effect of five biological agents against cucumber and tomato root-knot nematodes in greenhouse during 2011-2012.10 billions/g Verticillium chlamydosporium DP (0.2 kg/667 m2 )and 0.02 billions/g Paecilo-myces lilacinus GR (5 kg/667 m2 )were manually applied,and 2% abamectin+polysaccharide EC (3 000×),1 billion cfu/mL Bacillus cereus AS (6 L/667 m2 )and 1.8% abamectin EC (500×)were applied by drenching at the stage that the cucumber seedlings were transplanted into greenhouse.All the bioagents were reapplied once 20 days after the transplantation.Each treatment had 4 replicates,and the cucumber and tomato seedlings treated with water were used as the control.The results showed that all these bioagents could increase the cucumber and tomato production and

  5. HEAVY METALS ACCUMULATION IN GREENHOUSE VEGETABLE PRODUCTION SYSTEMS AND ITS ECOLOGICAL EFFECTS%设施蔬菜生产系统重金属积累特征及生态效应

    Institute of Scientific and Technical Information of China (English)

    陈永; 黄标; 胡文友; 杨岚钦; 毛明翠

    2013-01-01

    To study spatial variability of soil heavy metals may help reveal effects of human activities on soil heavy metals accumulation and provide important basic data for soil utilization and its pollution risk assessment.Based on systematical analysis of heavy metals,arsenic (As),cadmium (Cd),copper (Cu),mercury (Hg),lead (Pb),zinc (Zn)in the environmental media,such as soil,irrigation water,fertilizer,and plants of a greenhouse vegetable production system typical of the suburbs of Nanjing,spatial variability and accumulation of heavy metals in the soil was explored causes of the accumulation analyzed,and effect of the accumulation on plant uptake of heavy metals in this system discussed.Results show that (1) accumulation of Cu,Hg,Pb,and Zn in the soil was significant compared with that in open fields,and the average contents of Cu,Hg,and Pb in the soil were higher than the criteria set in the Environmental Quality Evaluation Standard for Farmland in Greenhouse Vegetable Production ; (2) Large amounts of agro-inputs significantly affected spatial variability of soil properties,and hence,the spatial variability of soil Cu,Hg,Pb,and Zn in a similar way,for these elements were closely correlated with soil properties; and (3) The changes in soil properties and the accumulation of heavy metals strongly affected leaf vegetable' s uptake of heavy metals,and the former played a more important role.%研究土壤重金属的空间变异特征,可以揭示人为活动对土壤中重金属积累特征的影响,进而为土壤利用、污染风险评价提供重要的基础资料.选取南京市郊区一处典型的设施蔬菜生产系统为研究对象,测定了土壤、灌溉用水、肥料、蔬菜等介质中重金属砷(As)、镉(Cd)、铜(Cu)、汞(Hg)、铅(Pb)、锌(Zn)含量,研究了土壤中重金属的空间变异及积累特征,分析了积累产生的原因,讨论了系统中作物的重金属积累效应.结果表明:(1)与露天蔬菜地相比,设施蔬菜地土壤

  6. Briquettes of plant remains from the greenhouses of Almeria (Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Callejon-Ferre, A. J.; Lopez-Martinez, J. A.

    2009-07-01

    Since ancient times, plant biomass has been used as a primary fuel, and today, with the impending depletion of fossil fuels, these vegetal sources constitute a cleaner alternative and furthermore have a multitude of uses. The aim of the present study is to design a method of recycling and reuse of plant wastes from intensive agriculture under plastic, by manufacturing briquettes in an environmentally friendly manner. In Almeria (SE Spain), agriculture generates 769,500 t year{sup -}1 of plant remains from greenhouse-grown horticultural crops, a resource currently used for composting and for producing electricity.With the machinery and procedures of the present study, another potential use has been developed by detoxifying and eliminating the plastic wastes of the original biomass for the fabrication of briquettes for fireplaces. The results were slightly inferior to the commercial briquette from other non-horticultural plant materials (no forestry material), specifically 2512 kJ kg{sup -}1, in the least favourable case. On the contrary, the heating value with respect to the two charcoals was significantly lower, with a difference of 12,142 kJ kg{sup -}1. In conclusion; a procedure, applicable in ecological cultivation without agrochemicals or plastic cords, has been developed and tested to reuse and transform plant materials from intensive cultivation into a stable non-toxic product similar to composite logs, applicable in commercial settings or in residential fireplaces. (Author) 48 refs.

  7. 塑料薄膜覆盖对牛粪便温室气体排放的影响%Effects of plastic sheet covering on greenhouse gas emission from beef cattle manure during storage

    Institute of Scientific and Technical Information of China (English)

    孙凯佳; 戚鑫; 付彤; 李改英; 廉红霞; 高腾云

    2015-01-01

    为控制短期贮存畜禽粪便的温室气体排放,该文研究了塑料薄膜覆盖对肉牛粪便短期贮存过程中温室气体排放量的影响。试验采用静态箱-气相色谱法观测了秋季(日均22.87℃)肉牛粪便自然露天堆放(对照组)和塑料薄膜覆盖堆放(覆盖组)时温室气体的排放通量。结果表明:秋季覆盖塑料薄膜贮存粪便可使N2O和CO2的日均排放通量分别降低94.85%(P<0.01)和88.85%(P<0.01),并在试验前期(0~9 d)使CH4的日均排放通量降低了43.37%(P<0.05),但随后的10~30 d,覆盖组粪便CH4的日均排放通量极显著高于对照组(P<0.01)。结论:当环境温度在17.23~30.35℃时,覆盖塑料薄膜可以降低堆放贮存(0~30 d)粪便N2O和CO2的排放通量以及堆放初期(0~9 d)CH4的排放通量。因此,塑料薄膜覆盖贮存法可显著降低粪便堆放初期的温室气体排放。%In order to assess the effects of plastic sheet covering on CH4, N2O and CO2 emissions during short-term storage of beef cattle manure, the greenhouse gas emission rate was investigated in autumn (September 7, 2013 - October 6, 2013, average air temperature was 22.87℃) by the static chamber - gas chromatography (GC) method. Meanwhile, ambient air temperatures and manure temperatures (10 cm below the surface) were measured every 5 minutes using automatic temperature recorder. On the first day, manure samples were collected from the Simmental beef cattle (18-19 months old, average weight of 500 kg), mixed, homogenized and divided into 6 replicate piles (the length, width and height of every pile were 100, 100 and 20 cm, respectively). Every pile had 2 sampling sites. The following two different treatments were included in this experiment: natural storage group (control group) and plastic sheet cover storage group (covering group), and every group included 3 replicate piles and a total of 6 sampling sites. The

  8. The Status and Technique Requirement of Soil Fertilization and Irrigation for Fruit Vegetable in Greenhouse%京郊设施果类蔬菜土肥水管理现状及技术需求

    Institute of Scientific and Technical Information of China (English)

    王丽英; 赵小翠; 曲明山; 袁会敏; 陈清; 赵永志; 王克武

    2012-01-01

    北京郊区设施蔬菜发展迅速,通过对京郊集约化设施果类蔬菜生产中土肥水管理现状的调查发现,水肥投入量过大,养分投入比例不合理是主要问题.蔬菜每年用水量为7 500~10 500 m3/hm2,番茄、黄瓜、椒类、茄子总养分(N-P2O5-K2O)投入量分别为1 206-504-782,1 426-735-1 101,1 298-599-915,1 255-631-958 kg/hm2;肥料选用与施肥灌溉技术缺乏指导,50%以上农民不懂如何选择肥料,有机肥的62%来自养殖场或农民自家堆制,68%和26%的农民仍凭经验施肥和灌溉.因水肥管理不当及连作导致土壤线虫病害、土壤板结、酸化、盐演化等问题普遍,其中,根结线虫障碍的比重最高,占29%,无障碍土壤的比例仅占11%.京郊区土肥水现存问题在于管理和技术条件的制约,水肥管理和土壤质量综合提升技术成果转化与物化有待加强,为此提出开展水肥资源高效利用和土壤质量综合提升技术研发,探讨适合分散经营的技术推广机制与模式的技术需求.%Vegetable planting with intensive degree developed very fast in recent years. Investigation was conducted to explore the status of soil, water and fertilizer of greenhouse fruit vegetables in Beijing suburb. The result showed that excessive inputs of irrigation and fertilization,the unbalanced ratio of nutrient of N,P,K. The irrigation rate of fruit vegetable are 7 500 to 10 500 m3/ha for farmers. The fertilization rate of tomato was at 1 206 kg N,504 kg P2O5,782 kg K2O and 1 426 kg N,735 kg P2O5,1 101 kg K2O for cucumber,1 298 kg N,599 kg P2O5,915 kg K2O for pepper and 1 255 kg N, 63 lkg P2O5,958 kg K2O for eggplant per hectare respectively. The selection of fertilizer type could not be paid attention and fertigation technique was not widespread used. The 62% of the organic fertilizer was bought from breeding factory directly and was composted with conventional method by partly farmers. And more than 50% farmers didn't know

  9. Manejo de irrigação para o feijão-de-metro, nas fases vegetativa e produtiva, em ambiente protegido Irrigation scheduling for asparagus bean in vegetative and productive stages in greenhouse

    Directory of Open Access Journals (Sweden)

    Wellington G. da Silva

    2012-09-01

    Full Text Available O manejo adequado da irrigação é uma prática agrícola que requer informações para cada cultura explorada, em particular nas fases fenológicas do ciclo produtivo pois muitas espécies possuem períodos críticos durante os quais o estresse hídrico causa sérias reduções na produção. Este trabalho teve, como objetivo, avaliar o efeito de cinco níveis de potencial matricial de água no solo sobre o crescimento e produção do feijão-de-metro. O experimento foi conduzido em casa de vegetação, na área experimental pertencente ao Departamento de Engenharia da Universidade Federal de Lavras, Lavras, MG. O delineamento experimental foi o de blocos casualizados, em esquema fatorial 5 x 2, com quatro repetições. Os tratamentos foram constituídos de cinco potenciais matriciais de água no solo como indicativos do momento de irrigar (-15, -35, -55, -75 e -95 kPa, em duas fases fenológicas (vegetativa e produtiva, monitorados por sensores instalados a 0,15 m de profundidade. Os resultados permitiram concluir que a fase mais sensível ao déficit hídrico foi a produtiva e que a irrigação realizada no potencial matricial em torno de -15 kPa induziu a melhor resposta da cultura quanto ao desenvolvimento, produção e qualidade das vagens.Proper irrigation water management requires knowledge on each exploited crop; particularly regarding vegetative and productive phases since many species have critical periods during which water stress causes serious yield reductions. This study was undertaken so as to assess the effect of five matric potential levels on asparagus bean growth and yield. The experiment was conducted under greenhouse conditions at the experimental area of Department of Engineering, Federal University of Lavras, Lavras, MG. The experimental design was randomized blocks in factorial 5 x 2. The treatments consisted of five matric potentials as indicative of the irrigation scheduling -15 -35 -55 -75 -95 kPa and at two

  10. Design of environment monitoring system for vegetable greenhouse based on internet of things%基于物联网的蔬菜大棚环境监控系统设计

    Institute of Scientific and Technical Information of China (English)

    赵丽丽; 刘成忠

    2014-01-01

    In order to solve environmental monitoring problem of vegetable greenhouses,an environ-mental monitoring system based on internet of things was designed,the sensor gateway development process of this system was introduced.Embedded ARM processor was the core of the gateway hardware, multi-node monitoring as well as the processing and transmission of the environmental information were re-alized.The software was based on the Linux operating system,with a digital noise reduction technology, high-precision monitoring data was obtained.The application of this system showed that it not only realized distributed multi-node environment parameter monitoring,but also achieved a variety of intelligent services by data mining.%针对蔬菜大棚环境监控问题,设计了一种基于物联网的环境监控系统,介绍了系统传感网关的开发过程。网关硬件以嵌入式ARM处理器为核心,实现了多节点监控以及环境信息的处理与传输。软件采用Linux 操作系统,配合数字降噪等技术,获得了高精度的监控数据。通过试验证明,该系统不仅完成了分布式多节点环境参数监控,还能通过对数据的深度挖掘,实现多种智能化服务。

  11. Improvement and implementation of intelligent irrigation system in vegetable greenhouses in Zhangzhuang Town of Peixian County%沛县张庄镇蔬菜大棚智能灌溉系统的改进与实现

    Institute of Scientific and Technical Information of China (English)

    刘天飞

    2015-01-01

    According to the investigation on provincial demonstrative base of intelligent irrigation and water conservation system in vegetable greenhouses in Zhangzhuang Town of Peixian County of Jiangsu Province,this paper analyzes the problems including high current drain,irrigating by experience,high price and being difficult to be popularized.Based on that,we design a low-cost intelligent micro-irrigation controller.Taking single chip computer STC89C52 as the core,this controller realizes intelligent detection and control of the maj or parameters including the tempera-ture and humidity from aspects of hardware and software and thus realizes intelligent irrigation. This intelligent micro-irrigation controller is economical,practical,easy to be popularized,and can accomplish the aim of saving water.%针对江苏沛县张庄镇蔬菜大棚智能灌溉节水系统省级示范基地的调查,分析了该智能灌溉节水系统耗电量大、凭经验灌溉、价格高昂和不易推广等问题,设计出一款价格低廉的智能微灌控制器。该控制器以STC89 C52单片机为核心,从硬件和软件两个方面实现了温度、湿度等主要参数的智能检测与控制,实现了智能灌溉。该智能微灌控制器经济实用,易于推广,能达到节约水资源的目的。

  12. INSECTICIDES FOR CONTROL OF GREENHOUSE WHITEFLY (TRIALEURODES VAPORARIORUM WESTW. IN GROWING OF TOMATO IN GREENHOUSES

    Directory of Open Access Journals (Sweden)

    Vinelina Yankova

    2015-12-01

    Full Text Available A screening of plant protection products for their effectiveness against the greenhouse whitefly (Trialeurodes vaporariorum Westw. was made in growing of tomatoes in greenhouses. The experiments were conducted during the period 2009-2014 in unheated greenhouses in the „Maritsa” Vegetable Crops Research Institute, Plovdiv. It was found that the products Confidor Energy OD 0,08%, Actara 25 WG 0,03%, Mospilan 20 SP 0,02% and Eforia 45 CS 125 ml/da have very good effectiveness against adults and larvae of the greenhouse whitefly. Phytopesticide Piros 0,08% has good effectiveness against adults and satisfactory against the greenhouse whitefly larvae. This product could be used as an alternative to control this pest in integrated and organic production of tomatoes in greenhouses.

  13. Object-Based Greenhouse Horticultural Crop Identification from Multi-Temporal Satellite Imagery: A Case Study in Almeria, Spain

    Directory of Open Access Journals (Sweden)

    Manuel A. Aguilar

    2015-06-01

    Full Text Available Greenhouse detection and mapping via remote sensing is a complex task, which has already been addressed in numerous studies. In this research, the innovative goal relies on the identification of greenhouse horticultural crops that were growing under plastic coverings on 30 September 2013. To this end, object-based image analysis (OBIA and a decision tree classifier (DT were applied to a set consisting of eight Landsat 8 OLI images collected from May to November 2013. Moreover, a single WorldView-2 satellite image acquired on 30 September 2013, was also used as a data source. In this approach, basic spectral information, textural features and several vegetation indices (VIs derived from Landsat 8 and WorldView-2 multi-temporal satellite data were computed on previously segmented image objects in order to identify four of the most popular autumn crops cultivated under greenhouse in Almería, Spain (i.e., tomato, pepper, cucumber and aubergine. The best classification accuracy (81.3% overall accuracy was achieved by using the full set of Landsat 8 time series. These results were considered good in the case of tomato and pepper crops, being significantly worse for cucumber and aubergine. These results were hardly improved by adding the information of the WorldView-2 image. The most important information for correct classification of different crops under greenhouses was related to the greenhouse management practices and not the spectral properties of the crops themselves.

  14. GREENHOUSE BRITAIN

    Directory of Open Access Journals (Sweden)

    David Haley

    2008-10-01

    Full Text Available We believe that the cultural landscape is largely formed by the dominant cultures of a place. “It is formed by a sometimes conflicted, sometimes consensual discourse or narrative from an array of stories, observations and intentions, first spoken by people of these dominant cultures and thereafter enacted on the ground. To our view, such a story has certain fluidity about it, and may change directions for any number of reasons. This work, Greenhouse Britain, is designed literally to express what the risingof waters would mean to the landscape of the island. It takes the 3 positions of defense, withdrawal and then defense, withdrawal to the high grounds. We suggest that the existing plans for greenhouse emissions control will be insufficient to keep temperature rise at 2° or less. In fact, we believe that the tipping point is past. In this context, the rising ocean becomes a form determinant. By “form determinant”, we mean, the rising ocean will determine many of the new forms that culture, industry and many other elements of civilization will have to take. There is another piece of this picture that we wish to give Voice to. That is up until this present rising of the world oceans, the creators of Western civilization have held and enacted the belief that all limitations in the physical world, particularly in the ecological world are there to be used and overcome. We think that the rising ocean is an opportunity for transformation, but it is exactly the reverse of a new frontier to overcome from civilization’s perspective. Now, from the ocean’s perspective, its boundary is perhaps a continuing, evolving transforming new frontier. Therefore, assuming a rapid rise of waters, even for a modest 5 meters in 100 years, there are apparently no models of precedence, no information, design, nor planning on the table, with the exception of ocean defenses and typical development models, albeit more energy efficient ones. It is the intention of

  15. Plastic Surgery

    Science.gov (United States)

    ... Surgery? A Week of Healthy Breakfasts Shyness Plastic Surgery KidsHealth > For Teens > Plastic Surgery Print A A ... forehead lightened with a laser? What Is Plastic Surgery? Just because the name includes the word "plastic" ...

  16. Evaluation of Resistance of Cucumber Cultivars to the Vegetable Leafminer (Liriomyza sativae Blanchard (Diptera: Agromyzidae in Greenhouse Evaluación de Resistencia de Cultivares de P epino a la Mosca Minadora (Liriomyza sativae Blanchard (Diptera: Agromyzidae en Invernadero

    Directory of Open Access Journals (Sweden)

    Moslem Basij

    2011-09-01

    Full Text Available The leafminer, Liriomyza sativae Blanchard, is distributed around the world and is an important pest of vegetables and ornamentals. Given the resistance potential of the leafminer to current insecticides, the use of resistant plant cultivars and parasitoids could be effective integrated pest management (IPM strategies against it. Cucumber (Cucumis sativus L. is a preferred host for this insect. Seventeen cultivars of cucumber have been evaluated to study resistance mechanisms to L. sativae. All cucumber cultivars were evaluated in screening tests in greenhouse with indices such as the number of leafminer stings, the number of larval mines, the proportion of larval mines to leafminer stings, and the rate of injury. Significant differences (p La mosca minadora, Liriomyza sativae Blanchard, se ha distribuido por el mundo en recientes años y es una plaga importante de vegetales y plantas ornamentales. La resistencia potencial de la mosca minadora a insecticidas corrientes, el uso de cultivares resistentes, y parasitoides podrían ser estrategias efectivas en su manejo integrado de plagas (IPM. El pepino (Cucumis sativus L. es un huésped preferido por este insecto. Diecisiete cultivares de pepino fueron evaluados para estudiar los mecanismos de resistencia a L. sativae, en pruebas de screening en invernadero usando índices tales como número de marcas hechas por la mosca, número de galerías larvales, proporción entre galerías larvales y marcas hechas por la mosca, y tasa de daño. Se observaron diferencias significativas (p < 0,01 entre cultivares, así como correlaciones significativas entre los índices evaluados. Los cultivares de pepino se clasificaron por el método cluster basado en todos los caracteres medidos en cuatro grupos: susceptible, semi susceptible, semi resistente, y resistente. Los ensayos de resistencia a antibiosis de los cultivares se condujeron en cámara de crecimiento y se evaluaron con algunos índices biológicos de

  17. Effects of cover properties, ventilation rate and crop leaf area on tropical greenhouse climate

    NARCIS (Netherlands)

    Impron, I.; Hemming, S.; Bot, G.P.A.

    2008-01-01

    Experimental results and validation of a simple greenhouse climate model are analysed according to data sets from six prototype greenhouses with three different plastics (reference N0, and two levels of near-infrared reflecting pigments N1 and N2); two ratios of ventilation openings to greenhouse

  18. Effects of cover properties, ventilation rate and crop leaf area on tropical greenhouse climate

    NARCIS (Netherlands)

    Impron, I.; Hemming, S.; Bot, G.P.A.

    2008-01-01

    Experimental results and validation of a simple greenhouse climate model are analysed according to data sets from six prototype greenhouses with three different plastics (reference N0, and two levels of near-infrared reflecting pigments N1 and N2); two ratios of ventilation openings to greenhouse co

  19. N2O emission from an intensively managed greenhouse vegetable field in Nanjing suburb,Jiangsu Province of East China%南京市郊区集约化大棚蔬菜地N2O的排放

    Institute of Scientific and Technical Information of China (English)

    贾俊香; 张曼; 熊正琴; 李叶

    2012-01-01

    By using static opaque chamber and gas chromatography, this paper studied the dynamic changes of N2O fluxes and their relationships with soil temperature, soil moisture content, and soil nitrate and ammonium contents in an intensively managed greenhouse celery-Tung choy-Bok choy-amaranth rotation field and in a bare fallow land in Nanjing suburb. The cumulative N2O emission from the rotation vegetable field was as high as 137. 2 kg N · hm-2, being significantly higher than that from the bare fallow land (29. 2 kg N · hm-2 ) , and the N2O-N emission factor of the rotation vegetable field ecosystem was up to 4. 6% . In the rotation field, the planting of Tung choy had the greatest contribution to the annual cumulative N2O emission, occupying 53. 5% of the total, followed by the planting of Bok choy (31.9%), celery field (4.5%), and amaranth (4.8%). The N2O flux of the rotation field had significant positive correlation with soil temperature, the Ql0 being 2. 80, but no significant correlations with soil moisture content and soil nitrate and ammonium contents.%采用静态暗箱-气相色谱法,研究了南京市郊区集约化生产管理下,芹菜-空心菜-小白菜-苋菜轮作菜地与休闲裸地的N2O排放通量的动态变化,及其与土壤温度、湿度以及NO3--N和NH4+-N含量的关系.结果表明:轮作菜地的N2O累积排放量达137.2kg N·hm-2,显著大于休闲裸地(29.2 kgN-hm-2);轮作菜地生态系统N2O-N的排放系数高达4.6%.4种蔬菜地中,空心菜地对轮作菜地的周年累积排放量贡献最大,为53.5%,小白菜地次之,为31.9%,芹菜地和苋菜地最小,分别为4.5%和4.8%.轮作菜地的N2O排放通量与土壤温度呈显著正相关,Q10为2.80;土壤湿度以及NO3--N和NH4+-N含量与轮作菜地的N2O排放通量之间的相关性不显著.

  20. CRESCIMENTO E DESENVOLVIMENTO DA ALFACE (Lactuca sativa L. CONDUZIDA EM ESTUFA PLÁSTICA COM FERTIRRIGAÇÃO EM SUBSTRATOS GROWTH AND DEVELOPMENT OF LETTUCE (Lactuca sativa L. IN A PLASTIC GREENHOUSE WITH FERTIRRIGATION IN SUBSTRATES

    Directory of Open Access Journals (Sweden)

    Luis Aquiles Martins Medeiros

    2001-04-01

    Full Text Available Foram conduzidos dois experimentos, um cultivo no outono e outro no inverno de 1998, em estufa plástica localizada no Departamento de Fitotecnia da Universidade Federal de Santa Maria, com o objetivo de estudar a influência da fertirrigação em substratos no crescimento e desenvolvimento da alface, cultivar Brisa. Os tratamentos, com e sem fertirrigação, foram constituídos pelos substratos húmus de minhoca mais casca de arroz natural (H+CN, húmus de minhoca mais casca de arroz carbonizada (H+CC e solo como testemunha, constituindo um bifatorial 3x2. A fertirrigação foi realizada em função da condutividade elétrica (CE da solução drenada dos substratos. O delineamento experimental utilizado foi de blocos casualizados com quatro repetições. Semanalmente, foram determinados o número de folhas por planta, a massa fresca e seca da parte aérea das plantas e o índice de área foliar. Avaliou-se, ainda, a capacidade de retenção de água (CRa dos substratos isolados e das misturas, antes e após os cultivos. A CRa dos substratos aumentou ao longo dos cultivos enquanto a do solo permaneceu constante. Os substratos irrigados com solução nutritiva proporcionaram maior número de folhas, maior produção de massa fresca e seca da parte aérea e maior índice de área foliar do que quando irrigados apenas com água, sendo que os substratos H+CN e H+CC foram significativamente mais produtivos do que o substrato testemunha em ambos os cultivosIn order to study the effects of fertirrigation in growing substrates on the development of lettuce cultivar Brisa, two essays were conducted, one during the fall of 1998 and the other during the winter, in a plastic greenhouse in the Federal University of Santa Maria. The treatments with and without fertirrigation were constituted by earthworm humus plus rice hulls (H+CN, earthworm humus plus carbonized rice hulls (H+CC and pure soil as check. The fertirrigation timing was established by monitoring

  1. Effect of Simple Plastic-film Greenhouse on Environmental Factors in Crown of Lane Late Navel Orange in Winter%简易塑料大棚对冬季晚棱脐橙树冠内环境因子的影响

    Institute of Scientific and Technical Information of China (English)

    姚锋先; 管冠; 谢金招; 钟八莲

    2015-01-01

    Taking 4-year-old lane late navel orange as research material , the author used a simple plastic-film greenhouse to study the change characteristics of temperature and humidity in the crown of tree .The results showed that the temperature and hu-midity in the tree crown in the simple plastic greenhouse were closely relevant to those in the open air ( the correlation coefficient R2 was 0.7359 and 0.7489, respectively), the average temperature in greenhouse was 1.6℃higher, and the humidity was slightly low-er than those in the open air .The temperature gap between inside and outside of greenhouse was averagely 4.8℃( high inside and low outside) in daytime, and -1.2℃in night.Both the temperature rising in daytime and the temperature inversion in night hap-pened in the greenhouse , which were not affected by the types of weather .%以4年生枳壳砧晚棱脐橙树为试验材料,采用简易塑料大棚设施栽培模式,研究了设施条件下树冠内环境因子的变化特征,结果表明:简易塑料大棚树冠内温湿度与外界大气环境温湿度密切相关(相关系数R2分别为0.7359和0.7489),大棚内平均温度提高约1.6℃,湿度略有下降。对白天和夜晚设施内外温度差的分析表明,白天设施内平均增温4.8℃,晚上则恰好相反,内外温差为-1.2℃;设施内白天升温和夜间“逆温”现象并存,且不受天气类型的影响。

  2. Genetic variation and plasticity of Plantago coronopus under saline conditions

    Science.gov (United States)

    Smekens, Marret J.; van Tienderen, Peter H.

    2001-08-01

    Phenotypic plasticity may allow organisms to cope with variation in the environmental conditions they encounter in their natural habitats. Salt adaptation appears to be an excellent example of such a plastic response. Many plant species accumulate organic solutes in response to saline conditions. Comparative and molecular studies suggest that this is an adaptation to osmotic stress. However, evidence relating the physiological responses to fitness parameters is rare and requires assessing the potential costs and benefits of plasticity. We studied the response of thirty families derived from plants collected in three populations of Plantago coronopus in a greenhouse experiment under saline and non-saline conditions. We indeed found a positive selection gradient for the sorbitol percentage under saline conditions: plant families with a higher proportion of sorbitol produced more spikes. No effects of sorbitol on fitness parameters were found under non-saline conditions. Populations also differed genetically in leaf number, spike number, sorbitol concentration and percentages of different soluble sugars. Salt treatment led to a reduction of vegetative biomass and spike production but increased leaf dry matter percentage and leaf thickness. Both under saline and non-saline conditions there was a negative trade-off between vegetative growth and reproduction. Families with a high plasticity in leaf thickness had a lower total spike length under non-saline conditions. This would imply that natural selection under predominantly non-saline conditions would lead to a decrease in the ability to change leaf morphology in response to exposure to salt. All other tests revealed no indication for any costs of plasticity to saline conditions.

  3. Simple greenhouse climate model as a design tool for greenhouses in tropical lowland

    NARCIS (Netherlands)

    Impron, I.; Hemming-Hoffmann, S.; Bot, G.P.A.

    2007-01-01

    Six prototypes plastic greenhouses were built in the tropical lowlands of Indonesia. The geometrical dimensions were designed using computational fluid dynamics (CFD) by taking local climate parameters as static reference boundary conditions. It is necessary to evaluate the climate dynamics inside

  4. Persisting Plastic Addiction

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The policy on curbing plastic shopping bag use implemented three years ago has produced mixed results In a bustling farmers’market tucked in a narrow street in Xisanqi residential community in north Beijing,stalls selling vegetables,fruits and other foods line the sidewalk.

  5. 山东寿光设施菜地土壤砷含量及形态%Concentration and speciation of arsenic in greenhouse vegetable soil in Shouguang County of handong Province

    Institute of Scientific and Technical Information of China (English)

    胡留杰; 曾希柏; 白玲玉; 李莲芳

    2011-01-01

    通过典型区域采样调查,系统探讨了山东寿光市设施菜地中砷的含量及其形态特征.结果表明:设施菜地表层(0~20 cm)和亚表层(20~40 cm)土壤中总砷含量分别为8.27、7.93 mg.kg-1,是对照土壤的1.19和1.23倍,易溶性砷(AE-As)含量分别为0.13、0.06 mg.kg-1,是对照土壤的1.63和3.00倍;土壤中的砷主要以残渣态砷(O-As)存在,其含量占总砷的63.0%以上,其他形态砷含量依次为铁型砷(Fe-As)>钙型砷(Ca-As)>铝型砷(Al-As)>AE-As;随着种植年限的延长,土壤中AE-As含量显著增加,Al-As含量也有不同程度提高,种植15 a设施菜地表层和亚表层土壤中的AE-As含量分别比对照提高了75.0%和150.0%,Al-As含量分别提高了51.6%和190.4%,而Fe-As和Ca-As含量则均有不同程度的下降.%A sampling survey was conducted in the typical areas in Shouguang County of Shandong Province to study the characteristics of arsenic (As) concentration and speciation in greenhouse vegetable soil. The total As concentration in the surface (0-20 cm) and subsurface (20-40 cm)soil was averagely 8. 27 and 7.93 mg· kg-1, being 19% and 23% higher than that of the control (open field soil), and the soluble As (AE-As) concentration was 0. 13 and 0. 06 mg · kg-1, 63%and 200% higher than that of the control, respectively. The ratio of residual As (O-As) to total arsenic reached more than 63.0%, and the concentrations of different As speciation decreased in the order of O-As > iron-bound As (Fe-As) > calcium bound As (Ca-As) > aluminum bound As (AlAs) > AE-As. With the increasing planting years, the AE-As concentration enhanced significantly,and the Al-As concentration also increased to some degree. After 15 years planting, the AE-As concentration in surface and subsurface soil increased by 75.0% and 150. 0%, and Al-As concentration increased by 51.6% and 190. 4%, respectively, while the concentrations of Fe-As and Ca-As all decreased to some degree.

  6. Soil Bulk Density and Porosity in Greenhouse Vegetables Field under the Optimized Fertilization Treatment%优化施肥处理下设施菜地土壤容重与孔隙度的变化

    Institute of Scientific and Technical Information of China (English)

    张宝峰; 曾路生; 李俊良; 陈清

    2013-01-01

    Soil bulk density and porosity influence the bioavailability of soil nutrient and crop growth, and are closely related to the cultivation, fertilization, irrigation and other agricultural management measures. In order to research soil environmental quality and explore the optimal fertilization mode under Greenhouse field conditions, soil bulk density, porosity and soil respiration intensity were studied under the optimized fertilization conditions, with the soil of no chemical fertilizer and manure for control in Shouguang Greenhouse vegetables field planting tomato, and the results showed that, compared with the control, the optimized fertilization treatments improved the soil bulk density and porosity conditions in a certain extent. Such measures reduced the soil bulk density by 3.73%to 14.93%and increased the soil total porosity by 4.18%to 15.79%. In the meantime, the average capillary porosity and the non capillary porosity increased by 8.07%and 8.94%, respectively. Soil respiration intensity enhanced by 23.4%to 34.6%in the root zone and by 9.6%to 106.9%in the non root zone compared with the control. Among them, the treatment with 8 t/hm2 of manure and 4 t/hm2 of straw blending broadcast, and topdressing 150 kg/hm2 of nitrogen in the growth period got the most obvious effect and should be recommended to apply in the production practice. The results also showed that the average soil respiration intensity in root zone was 62.91 mg/(kg·d) with about 1.8 times of 34.45 mg/(kg·d) in the non-root zone. Soil respiration intensity was parabolic relationship to soil bulk density and soil total porosity. When the soil bulk density was about 1.25 g/cm3 and total porosity was about 53%, the soil would have higher respiration intensity.%土壤容重与孔隙度影响土壤养分的有效性及作物生长,与耕作、施肥、灌溉等农业管理措施密切相关。为了研究设施农业条件下土壤环境质量的变化,探索较优施肥

  7. 纤维素膜降解性能及其在切分蔬菜保鲜中的应用研究%Application of Biodegradable Plastic Packaging Film on Preservation of Fresh-cut Vegetables

    Institute of Scientific and Technical Information of China (English)

    胡云峰; 杨秋月; 宋慧颖; 郭红莲

    2012-01-01

    The degradation of cellulose membrane, and the application of cellulose membrane in fresh vegetables are mainly investigated through studying its permeability, moisture permeability, and preservation. The results show that: 1 ) Different microbial has different degradation rate to cellulose membranes; 2 ) Cellulose packaging film's degradation performance is the best that it can be depredated fully after three days by inoculating Penicillium; 3 ) Cellulose packaging film's permeability is better than plastic film, resulting in the poor effects of green color and anti- browning when preserving fresh vegetables; 4 ) Cellulose membrane has so strong water vapor permeability that it's water retention is worse than the plastic packaging film.%主要研究了纤维素膜的降解性能,并通过其透气性、透湿性和保鲜效果三方面的实验来研究纤维素膜在蔬菜保鲜中的应用.结果表明:1)不同微生物对纤维素膜的降解速度有很大差异;2)纤维素保鲜包装膜降解性能好,采用接种青霉的方法,3天后膜达到全部降解;3)纤维素保鲜包装膜的透气性能优于塑料膜,导致保鲜蔬菜时护绿和防褐变效果差;4)纤维素保鲜包装膜的透湿性能较强,对包装的蔬菜保水性较塑料包装膜差.

  8. Plasticity theory

    CERN Document Server

    Lubliner, Jacob

    2008-01-01

    The aim of Plasticity Theory is to provide a comprehensive introduction to the contemporary state of knowledge in basic plasticity theory and to its applications. It treats several areas not commonly found between the covers of a single book: the physics of plasticity, constitutive theory, dynamic plasticity, large-deformation plasticity, and numerical methods, in addition to a representative survey of problems treated by classical methods, such as elastic-plastic problems, plane plastic flow, and limit analysis; the problem discussed come from areas of interest to mechanical, structural, and

  9. Current Soil Nutrient Status of Intensively Managed Greenhouses

    Institute of Scientific and Technical Information of China (English)

    HU Yun-Cai; SONG Zhi-Wen; LU Wen-Long; C.POSCHENRIEDER; U.SCHMIDHALTER

    2012-01-01

    Nine districts covering the main greenhouse vegetable areas in Tianjin Municipality of the North China Plain were selected for the soil investigation in 2010 to survey the current soil nutrient status (soil available N,P and K),acidification and salinization due to excessive input of fertilizers in greenhouses in Tianjin. The study showed that,in particular,soil available P content increased with the age of greenhouses.In contrast,our results did not reveal higher K accumulation and lowered pH in the greenhouse soils compared with cultivation in open fields.Over-fertilization,causing high NO3- accumulation,most likely resulted in salinity problems in the greenhouses.Ninety percent of the investigated greenhouse soils had electrical conductivity values of saturated paste extracts of 2-10 d S m-1,which might affect the yields of vegetable crops like green bean,pepper,cabbage,carrot,eggplant,lettuce,spinach,celery,cucumber and tomato. The findings of our survey of the current fertility and salinity problems in greenhouse soils suggest that there is an urgent need to improve the farmers' practices and strategies in fertilization management in greenhouses of China.Because education and the agricultural technical extension services may play a more important role in avoiding overuse of fertilizers,we suggest that current nutrient management practices should be improved in the near future through training of local farmers in farmers' schools and through strengthening the agricultural extension services with practical techniques.

  10. Accumulation and health risk of heavy metals in vegetables from harmless and organic vegetable production systems of China.

    Science.gov (United States)

    Chen, Yong; Hu, Wenyou; Huang, Biao; Weindorf, David C; Rajan, Nithya; Liu, Xiaoxiao; Niedermann, Silvana

    2013-12-01

    Heavy metal accumulation in vegetables is a growing concern for public health. Limited studies have elucidated the heavy metal accumulation characteristics and health risk of different vegetables produced in different facilities such as greenhouses and open-air fields and under different management modes such as harmless and organic. Given the concern over the aforementioned factors related to heavy metal accumulation, this study selected four typical greenhouse vegetable production bases, short-term harmless greenhouse vegetable base (SHGVB), middle-term harmless greenhouse vegetable base (MHGVB), long-term harmless greenhouse vegetable base (LHGVB), and organic greenhouse vegetable base (OGVB), in Nanjing City, China to study heavy metal accumulation in different vegetables and their associated health risks. Results showed that soils and vegetables from SHGVB and OGVB apparently accumulated fewer certain heavy metals than those from other bases, probably due to fewer planting years and special management, respectively. Greenhouse conditions significantly increased certain soil heavy metal concentrations relative to open-air conditions. However, greenhouse conditions did not significantly increase concentrations of As, Cd, Cu, Hg, and Zn in leaf vegetables. In fact, under greenhouse conditions, Pb accumulation was effectively reduced. The main source of soil heavy metals was the application of large amounts of low-grade fertilizer. There was larger health risk for producers' children to consume vegetables from the three harmless vegetable bases than those of residents' children. The hazard index (HI) over a large area exceeded 1 for these two kinds of children in the MHGVB and LHGVB. There was also a slight risk in the SHGVB for producers' children solely. However, the HI of the whole area of the OGVB for two kinds of children was below 1, suggesting low risk of heavy metal exposure through the food chain. Notably, the contribution rate of Cu and Zn to the HI were

  11. Algorithm of heating temperature for Chongqing's winter greenhouses

    Institute of Scientific and Technical Information of China (English)

    XIE Shou-yong; LI Xi-wen; YANG Shu-zi; YANG Ming-jin

    2007-01-01

    Internal temperature is crucial to plant growth in the greenhouse. We investigated the patterns of constructing and managing greenhouses in Chongqing, and developed an algorithm of heating temperature for closed winter plastic greenhouses under the conditions of no man-made illumination, no ventilation and hot wind machine as the heating equipment, which are the most adopted pattern of greenhouses in Chongqing area. The algorithm includes two functions of temperature outside the greenhouse, which calculate the values of the warming estimation coefficient (WEC) and the gap between temperatures inside and outside the greenhouse with the measured data of outside temperature, and then give the value of internal temperature; the heat rating of heating facilities required by a greenhouse can be determined by this algorithm with given values of floor area and internal temperature, measured outside temperature and calculated WEC. Verification of the algorithm demonstrates a desirable accuracy of estimation. Algorithms of computing heating temperature for greenhouses of different constructing and managing patterns and in different geographic conditions can also be derived in a similar way. This research presents a paradigm for developing a feasible method to fit out greenhouses with appropriate heating facilities, aiming at energy efficient and cost efficient production.

  12. Geothermal Greenhouse Information Package

    Energy Technology Data Exchange (ETDEWEB)

    Rafferty, K. [P.E.; Boyd, T. [ed.

    1997-01-01

    This package of information is intended to provide a foundation of background information for developers of geothermal greenhouses. The material is divided into seven sections covering such issues as crop culture and prices, operating costs for greenhouses, heating system design, vendors and a list of other sources of information.

  13. Utilizing Landsat TM Imagery to Map Greenhouses in Qingzhou, Shandong Province, China

    Institute of Scientific and Technical Information of China (English)

    ZHAO Geng-Xing; LI Jing; LI Tao; YUE Yu-De; T. WARNER

    2004-01-01

    To build a rapid and accurate method for greenhouse vegetable land information extraction using an index model derived from TM digital data of Qingzhou City, Shandong Province, based on a systematic analysis of the spectral characteristics of different land use types in the study area, a subset of the image was first made to eliminate the mountainous region not associated with vegetable distribution, and then water body pixels were masked. With this the V1 index model for greenhouse vegetable land extraction was developed. The index model indicated greenhouse vegetable land for Qingzhou in April 2002 was concentrated in the southeast and around rural residential areas. Field data used for an accuracy evaluation showed that greenhouse hectares determined with remote sensing were 95.9% accurate, and accuracy for the spatial distribution of greenhouse vegetable land cross checked with a random sample was 96.3%. Therefore, this approach provided an effective method for greenhouse vegetable land information extraction and has potential significance for management of greenhouse vegetable production in the study area, as well as North China.

  14. Medidas radiométricas em casas de vegetação com cobertura plástica na região de Campinas - SP Radiometric measurement of greenhouses with plastic cover at Campinas region- SP

    Directory of Open Access Journals (Sweden)

    Edilson Costa

    2011-06-01

    Full Text Available Com o objetivo de caracterizar as relações e alterações radiométricas em três casas de vegetação, cobertas com filme transparente de polietileno de baixa densidade (PEBD de camada simples com 150µm de espessura, tratado contra raios ultravioleta, sob ambientes distintos, foram realizados os experimentos durante o cultivo hidropônico de alface, cultivar Vera, na região de Campinas - SP, em diferentes períodos do ano, visando ao uso de dados experimentais de postos meteorológicos em substituição à necessidade de adquirir equipamentos de radiação para medições internas. As casas de vegetação eram de estrutura metálica de aço, de forma e volume idênticos. Coletaram-se a radiação solar global interna e externa (RSGI e RSGE, W m-2, a radiação fotossinteticamente ativa (RFA, µmol m-2 s-1 e a radiação ultravioleta, em 254; 312 e 365 nm (RUV, W m-2. Os resultados mostraram que as equações de regressão linear são estimativas aceitáveis na obtenção da radiação fotossinteticamente ativa em função da radiação solar global externa. Em ambientes fechados e climatizados, existe maior correlação entre a radiação fotossinteticamente ativa e a radiação solar global externa. A orientação das casas de vegetação não climatizadas não influencia no espalhamento interno da radiação fotossinteticamente ativa.The objective of this study was to characterize the radiometric relationship and changing in three greenhouses covered with transparent low density polyethylene film (PEBD with a 150µm single layer of low density polyethylene film, treated with compounds that inhibit rapid degradation by ultraviolet radiation, under effects of different environments. The experiments were conducted during hydroponics lettuce production of Vera variety at Campinas region-SP in different periods of the year, aiming the use of experimental data from meteorological stations in substitution of the needs to pursue radiometric

  15. National Greenhouse Gas Emission Inventory

    Data.gov (United States)

    U.S. Environmental Protection Agency — The National Greenhouse Gas Emission Inventory contains information on direct emissions of greenhouse gases as well as indirect or potential emissions of greenhouse...

  16. Effect of perchlorate in fertilisers on lettuce and fruit vegetables : Uptake and distribution of perchlorate in greenhouse soil-grown butterhead lettuce and solless-grown cucumber, sweet pepper, round and cherry tomate

    NARCIS (Netherlands)

    Voogt, W.; Eveleens, B.A.; Steenhuizen, J.W.; Vandevelde, I.; Vis, de R.; Lommel, van J.

    2014-01-01

    In 2013 traces of perchlorate were detected in fruits and vegetable samples. Because perchlorate (ClO4 -) is part of a group of substances (goitrogens) that may inhibit the uptake of iodine by the thyroid, these findings caused commotion in the markets. Fertilizers were named as one of the sources o

  17. Plastic Jellyfish.

    Science.gov (United States)

    Moseley, Christine

    2000-01-01

    Presents an environmental science activity designed to enhance students' awareness of the hazards of plastic waste for wildlife in aquatic environments. Discusses how students can take steps to reduce the effects of plastic waste. (WRM)

  18. Evapotranspiração máxima do pimentão cultivado em estufa plástica em função de variáveis fenométricas e meteorológicas Maximum evapotranspiration of sweet pepper grown in plastic greenhouse based upon meteorological and fenometrical variables

    Directory of Open Access Journals (Sweden)

    Carina R. Pivetta

    2010-07-01

    Full Text Available Objetivou-se, neste trabalho, estimar a evapotranspiração máxima (ETm do pimentão, em função da evaporação medida no evaporímetro de Piche (Epi exposto à radiação solar, com e sem a inclusão de variáveis meteorológicas e fenométricas pontuais de fácil mensuração. Em uma estufa plástica de 240 m² se realizaram medidas da ETm (em lisímetros de drenagem, Epi, temperatura do ar, déficit de saturação do ar (Di, índice de área foliar (IAF, altura de plantas (AP e número de folhas (NF. Ajustaram-se modelos para estimar a ETm com os dados coletados selecionando-se apenas os que apresentaram parâmetros angulares significativos pelo teste t a 5% de probabilidade de erro e coeficiente de determinação (R² > 0,80. Obtiveram-se os melhores modelos para a estimativa da ETm com os valores da Epi associados a um parâmetro de crescimento das plantas, como IAF, NF e AP. Foi possível estimar a ETm do pimentão com precisão aceitável (R² entre 0,81 e 0,91, para fins de irrigação sob estufa, por meio de modelos que incluíram a Epi e pelo menos uma variável fenométrica, preferencialmente a AP. A inclusão de Di medido às 9 h nos modelos em que se incluíram a Epi e AP ou NF ou IAF, melhorou a estimativa da ETm.The objective of this study was to estimate maximum evapotranspiration (ETm of sweet pepper inside a plastic greenhouse as a function of evaporation measured with "Piche" evaporimeter (Epi exposed to solar radiation, with and without easily measured meteorological and phenologic variables. The experiment was carried out inside a 240 m² plastic greenhouse. Daily ETm (measured with drainage lysimeters, Epi, air temperature, vapor pressure deficit (Di, leaf area index (LAI, plant height (PH, and leaf number (LN were measured. Models were fitted to estimate ETm using data collected on even days of the experimental period, selecting only models with parameters significant at 5% by t test and coefficient of determination (R

  19. Research on Remote Monitoring System of Vegetable Greenhouse Environment Based on DSP%基于DSP蔬菜大棚环境远程监测系统的研究

    Institute of Scientific and Technical Information of China (English)

    朱高中

    2016-01-01

    A remote detection system of greenhouse environment based on DSP and WiFi is designed. It takes TMS320LF2407 as the core control chip and completes the communication based on the WiFi technology,which can realize multi-channel environment monitoring function. The system consists of sensor module,DSP module,WiFi communication module and PC and so on. Through various types of sensors,the collected data is transmitted to the DSP controller for threshold judgment,and monitoring data is transferred to the host ma-chine through WiFi and wireless transmission network. The PC makes timely processing,achieving the purpose of man-machine interac-tion and remote control,successful realization of greenhouse environment remote study on monitoring. The experiment shows that the per-formance of greenhouse environment monitoring system is stable and reliable with accurate data,and has good application value and ex-tension prospects.%设计了一种基于数字信号处理器( DSP )和 WiFi 技术相结合的大棚温室环境远程检测系统。该系统以TMS320LF2407为控制核心芯片,基于WiFi技术进行通信,实现了多路环境监测的功能。系统主要由传感器采集模块、DSP信号处理模块、WiFi通信模块和PC等组成,通过各种类型的传感器将采集到的数据传给DSP控制器进行阈值的判断,并将监测的数据通过WiFi和无线传输网络传送给上位机,由上位机做出及时的处理,实现人机交互远程控制的目的,成功实现大棚环境远程监测的研究。实验结果表明,该大棚环境监测系统性能稳定可靠、数据精确,具有良好的应用价值和推广前景。

  20. 大棚菜农腰痛危险因素的结构方程模型分析%Structural equation model analysis of risk factors for low back pain among greenhouse vegetable-planting farmers

    Institute of Scientific and Technical Information of China (English)

    董红运; 杨曦伟; 于素芳

    2013-01-01

    目的 探讨大棚菜农腰痛的危险因素并估计其相对水平.方法 采用整群抽样方法,对某大棚种植区的639名大棚菜农进行回顾性问卷调查,并运用Smart PLS软件进行腰痛的结构方程模型分析.结果 潜变量腰痛的决定系数为0.827,动态负荷、静态负荷、力量施加、人体工效学环境、重复性负荷等潜变量与腰痛的结构系数分别为0.206、0.432、0.266、0.045、0.034,对腰痛的总体影响分别为0.206、0.432、0.266、0.333、0.034.结论 大棚菜农腰痛的主要危险因素是静态负荷、人体工效学环境、力量施加和动态负荷.%Objective To explore the risk factors of low back pain (LBP) among greenhouse vegetableplanting farmers and estimate the level of the effects.Methods A self-made questionnaire based on the Dutch Musculoskeletal Questionnaire and the Nordic Questionnaire was conducted to 639 greenhouse vegetableplanting farmers and then structural equation model was used to analyze the risk factors of LBP in SmartPLS software.Results The coefficient of determination of the model was 0.827,and the structural coefficients of dynamic loads,static loads,force exertion,ergonomic environment and repetitive loads on LBP were 0.21,0.43,0.27,0.045 and 0.034 respectively,and the total effects of the above latent variables on LBP were 0.21,0.43,0.27,0.33 and 0.034 respectively.Conclusion The main risk factors of LBP among greenhouse vegetableplanting farmers were static loads,ergonomic environment,force exertion and dynamic loads.

  1. Automatic Intelligent Management System of the Temperature and Humidity and Soil Moisture for the Vegetable Greenhouse%蔬菜大棚温湿度和土壤水分自动智能管理系统

    Institute of Scientific and Technical Information of China (English)

    孔国利; 席红旗

    2015-01-01

    针对蔬菜大棚温湿度和土壤水分控制难的问题,采用远距离无线串口透传技术设计了自动智能管理系统,主要由温湿度监控节点、土壤水分监控节点和管理主机组成。监控节点利用处理器 STM32 F103作为控制核心而设计,被均匀布置在大棚的各个区域,通过传感器 AM2302和 SM2802 M 分别采集大棚温湿度和土壤含水率,通过无线串口透传模块E17-TTL100-SMA发送到管理主机。管理主机上运行着采用 C#专业设计的管理软件,自动将接收到的数据进行处理、分析和显示,并存储在数据库SQL Server 2008中,如超出了预设的作物最佳生长范围,根据系统设定自动控制风机和灌溉管道阀开关进行调节。通过对西红柿大棚的实验表明:该系统实现了大棚温度湿度和土壤水分的实时智能管理,大大降低了管理者的劳动强度。%For the temperature, humidity and soil moisture control, the long-distance wireless serial transmission technolog is used to design an intelligent management system, which is composed of temperature and humidity monitoring nodes, soil moisture monitoring nodes and the management host computer.The monitoring nodes use the controller STM32F103 as the control core, and are distributed in different regions of greenhouse to collect the greenhouse tempera-ture and humidity and soil moisture information by the sensor AM2302 and SM2802 M, and send them to management host through the wireless serial transmission module through E17-TTL100-SMA.The management host is running the professional management software designed by C#, which can automaticly process, analyze and display the received data, and store it in a database SQL Server2008.According to the system settings, if the data is beyond the pre-set best range for the crop, it can automatically control the fan and the irrigation pipeline switch to adjust.The tomato greenhouse ex-periments show that the

  2. 水肥一体化椰糠栽培技术对日光温室蔬菜品质的影响%Effect of Cocopeat Planting Model Bas ed on Integrative Water an d Fertilizer Technology on Quality of Vegetables in Solar Greenhouse

    Institute of Scientific and Technical Information of China (English)

    张磊; 李文虎; 范淼珍; 王绪同; 蒋飞航; 司龙亭

    2016-01-01

    测定了自主研发的水肥一体化椰糠栽培技术对日光温室中7种蔬菜作物品质的影响。结果表明:该技术可以提高受试蔬菜可溶性糖、维生素C、可溶性固形物和矿质营养元素的含量,但对可溶性蛋白质、有机酸、硝酸盐含量等其他指标的影响表现出了品种差异。总体上来看,水肥一体化椰糠栽培技术提高了多个受试蔬菜品种的营养品质。%Abstratc: The effect on quality of 7 kinds of vegetables were tested by cocopeat planting model based on integrative water and fertilizer technology.The results showed that the contents of soluble sugar, vitamin C, soluble solids and mineral elements were improved under this new cocopeat planting model , and the content change of soluble proteins, organic acids and nitrate showed the difference of varieties.The new cocopeat planting model could improve the nutritional quality of vegetables in solar greenhouse.

  3. The greenhouse gases

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, R.

    1987-01-01

    The main greenhouse gases are carbon dioxide, methane, nitrous oxide, CFCs and ozone. They are greenhouse gases as they absorb radiation from the Earth and thus impede its emission back to space. CO{sub 2} is responsible for about half the enhanced greenhouse effect. A global warming of only a few degrees would have a profound effect on climate. Increased levels of CO{sub 2} promote plant growth, but may not benefit agriculture overall. Sea levels may rise. It is difficult to predict the effects of global warming in society. It would be possible to reduce the scale of the greenhouse effect by energy conservation, using alternative energy sources, and possibly by capturing CO{sub 2} from fossil fuel power stations and disposing of it on the ocean floor. 13 refs., 19 figs., 1 tab.

  4. GEOTHERMAL GREENHOUSING IN TURKEY

    Directory of Open Access Journals (Sweden)

    Sedat Karaman

    2016-07-01

    Full Text Available Use of renewable energy resources should be brought forward to reduce heating costs of greenhouses and to minimize the use of ever-depleting fossil fuels. Geothermal energy not only provides the heat required throughout plant growth, but also allow a year-long production. Geothermal resources with several other benefits therefore play significant role in agricultural activities. With regard to geothermal potential and implementation, Turkey has the 7th place in the world and the 1st place in Europe. Majority of country geothermal resources is used in greenhouse heating. The size of geothermal greenhouses increased 5 folds during the last decade and reached to 2500 decare. In this study, current status of geothermal greenhousing of Turkey was presented; problems and possible solutions were discussed.

  5. Greenhouse Module for Space System: A Lunar Greenhouse Design

    Directory of Open Access Journals (Sweden)

    Zeidler Conrad

    2017-02-01

    Full Text Available In the next 10 to 20 years humankind will return to the Moon and/or travel to Mars. It is likely that astronauts will eventually build permanent settlements there, as a base for long-term crew tended research tasks. It is obvious that the crew of such settlements will need food to survive. With current mission architectures the provision of food for longduration missions away from Earth requires a significant number of resupply flights. Furthermore, it would be infeasible to provide the crew with continuous access to fresh produce, specifically crops with high water content such as tomatoes and peppers, on account of their limited shelf life. A greenhouse as an integrated part of a planetary surface base would be one solution to solve this challenge for long-duration missions. Astronauts could grow their own fresh fruit and vegetables in-situ to be more independent from supply from Earth. This paper presents the results of the design project for such a greenhouse, which was carried out by DLR and its partners within the framework of the Micro-Ecological Life Support System Alternative (MELiSSA program. The consortium performed an extensive system analysis followed by a definition of system and subsystem requirements for greenhouse modules. Over 270 requirements were defined in this process. Afterwards the consortium performed an in-depth analysis of illumination strategies, potential growth accommodations and shapes for the external structure. Five different options for the outer shape were investigated, each of them with a set of possible internal configurations. Using the Analytical Hierarchy Process, the different concept options were evaluated and ranked against each other. The design option with the highest ranking was an inflatable outer structure with a rigid inner core, in which the subsystems are mounted. The inflatable shell is wrapped around the core during launch and transit to the lunar surface. The paper provides an overview of the

  6. Solar greenhouses in Minnesota

    Energy Technology Data Exchange (ETDEWEB)

    Polich, M.

    1981-12-01

    After a discussion of solar greenhouse phenomena and the potential for heat collection and food production, design recommendations are provided for attached heat collecting solar sunspaces and for attached food producing solar greenhouses. Also, design of a single solar structure to maximize heat collection and food production is considered. A method of predicting the performance for attached heat collecting solar sunspaces is given in which the solar savings fraction is calculated. (LEW)

  7. Calculation of NIR effect on greenhouse climate in various conditions

    NARCIS (Netherlands)

    Kempkes, F.L.K.; Hemming, S.

    2012-01-01

    In Northern regions of Europe glass is mainly used as greenhouse covering material whereas in Southern regions plastic films are commonly used. The develop-ment of covering material optical properties focuses on high light transmission, reduction of heating energy losses (higher latitudes) and reduc

  8. Effect of rotating different leaf vegetables with tomato in plastic tunnel on reuse of continuous cropping substrate%轮作叶菜对大棚番茄连作基质重复利用效果的影响

    Institute of Scientific and Technical Information of China (English)

    李威; 孟焕文; 程智慧; 周静; 柴喜荣; 梁静

    2012-01-01

    【Objective】The study was done to compare the effects of rotating different kinds of leaf vegetables in continuous cropping organic substrate on reducing or eliminating the continuous cropping obstacle of tomato under plastic tunnel cultivation.【Method】Green garlic,no-heading Chinese cabbage and leaf lettuce were respectively planted in the substrate with two season continuous production of tomato during winter fallow season under plastic tunnel.Tomato was planted as the aftercrop to investigate the effects of leaf vegetable rotation taking winter fallow substrate as CK1,the fresh substrate of the same formula as CK2 and the fresh substrate with peat and perlite as CK3.【Result】Except for the obvious change in EC value for the substrate of continuous cropping treatment,there is little alteration in EC value,pH value,bulk density and total porosity in the substrates of the other treatments before and after crop cultivation.That means those substrates are relatively stable in physical and chemical properties which are all within the optimal range for tomato growing and are appropriate for reuse to grow tomato.The contents of alkali hydrolysable nitrogen,available phosphorus and available potassium in substrate of different treatments are decreased by different degrees after rotating of different leaf vegetables.The plant growth and root vigor of aftercrop tomato during the whole growth period in treatment A and B show significant predominance to CK1 and close to or not significantly different from CK2 and CK3.The yield of tomato in treatment rotated with green garlic shows no significant difference from CK3 but significantly higher than CK2.The effect of rotating no-heading Chinese cabbage is just next to rotating green garlic.However,winter fallow(CK1) presents the lowest yield.As for fruit quality,the contents of soluble sugar,soluble protein,lycopene and sugar-acid ratio are higher in tomato rotated with garlic which show no significant difference

  9. 膜下微润带埋深对温室番茄土壤水盐运移的影响%Effect of tube depth of moistube-irrigation under plastic film mulching on soil water and salt transports of greenhouse tomato

    Institute of Scientific and Technical Information of China (English)

    张子卓; 牛文全; 许建; 张珂萌

    2015-01-01

    In order to verify the effect of moistube-irrigation under plastic film mulching on water and salt transport in tomato in slight alkaline soils under greenhouse conditions, three buried depths (10 cm, 15 cm, 20 cm) of moistubes of moistube-irrigation under plastic film mulching were designed and the effects of the moistube depths on water content and salinity of soils under (in tomato planting row) and between (between tomato rows) plastic films investigated. The results showed that the change trends in soil water content and salinity were consistent for different moistube depths under and between the plastic films. Under plastic film, soil water content increased initially and then decreased, whereas salinity decreased with time. Between plastic films, soil water content and salinity increased over time. The soil water content between plastic films was less than that under plastic film. With increasing soil depth, the difference in soil water content between under-film and between-films reduced. The difference of soil water content between under-film and between-films was maximal in surface soil. In 50-60 cm soil layer, water contents under plastic film and between plastic films were tend to be consistent. The deeper the moistube was, the higher the soil water content was. At fruiting stage of tomato, soil water contents were 23.31%, 24.46%and 22.42% for moistube depths of 20 cm, 15 cm and 10 cm, respectively. The difference in soil water content between under-film and between-films for 10 cm depth of moistube was less those for 15 cm and 20 cm depths of moistubes. Soil salinity under plastic film was less than that between plastic films, and with the increase of buried depth of moistube, the difference between under-film and between-films increased. In 0-40 cm layer under plastic film, soil was desalinated during the whole growth period of tomato, though the relative desalination rate decreased with increasing soil depth. Also in 0-40 cm soil layer, the nearer

  10. 植物油基含磷增塑剂DOPO-ESO的合成及应用%Synthesis and Application of Vegetable Oil-Based Phosphoric Plasticizer DOPO-ESO

    Institute of Scientific and Technical Information of China (English)

    胡云; 冯国东; 周永红

    2014-01-01

    大豆油经环氧化制成环氧大豆油(ESO),将ESO和9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)为原料,经开环反应,合成植物油基含磷阻燃增塑剂DOPO-ESO。并通过傅里叶变换红外谱图和核磁共振氢谱确认了其结构,以热重分析和氧指数测定仪分析了其热失重行为、阻燃性能。研究了DOPO-ESO用量对PVC体系力学性能的影响。结果表明,当其用量为40%时,PVC体系具有良好的力学性能,增塑效果与ESO相当;而极限氧指数从22.3%上升到了37.3%,说明该产物可有效地改善PVC增塑体系的阻燃性。%The vegetable oil-based flame retardant plasticizers DOPO-ESO was synthesized by ESO got by soybean oil epoxidation and 9,10-dihydro-9-oxa-phosphaphenanthrene-10-oxide (DOPO) as raw material through ring-opening reaction. The structure was confirmed by fourier transform infrared spectra and nuclear magnetic resonance hydrogen spectrum,thermo-gravimetric behavior andflame retardant properties were analyzed by thermal gravimetric analysis and oxygen index tester. The dosage of DOPO-ESO was studied on the mechanics performance of PVC systems. The results show that when the amount of DOPO-ESO reach 40%,PVC system has remarkable mechanical properties,and the effect of plasticizing is similar to ESO. While the limiting oxygen index rise from 22.3% to 37.3%,indicating that the product is effective to improve theflame retardancy to PVC plastisol system .

  11. Improved ventilation of open top greenhouses

    Energy Technology Data Exchange (ETDEWEB)

    Kats, G.; Thompson, C.R.; Kuby, W.C.

    1976-11-01

    In an attempt to reduce the greenhouse effect found when experiments are carried out in greenhouses, a new type of plant growth chamber was designed. Cylindrical chambers, 240 cm in height and 300 cm in diameter were constructed from Filon, a translucent corrugated acrylic fiberglass plastic sheet. A squirrel cage blower provided air at a rate of about 2.5 changes per minute. Activated charcoal filters were installed in the incoming air stream to remove photochemical oxidants to produce clean air. A 45/sup 0/ baffle was installed to displace the trailing edge mixing layer above the top of the chamber and thus sweep it clear by utilizing the vertical momentum component of the wind which is created locally.

  12. Dynamics of Western Flower Thrips and Its Natural Enemy Categories on Plastic Shed Cultivation Vegetables%大棚蔬菜西花蓟马的种群动态及其天敌种类

    Institute of Scientific and Technical Information of China (English)

    郝晨彦; 王相晶; 侯文杰; 施秀珍; 吴青君; 徐宝云; 张友军

    2011-01-01

    对北京地区大棚栽培蔬菜上西花蓟马种群动态和天敌种类进行调查.结果显示,春茬甜椒在定植30 d内,西花蓟马种群数量增长缓慢,但进入开花期,其数量迅速增长,到6月后持续保持在高数量水平.秋茬甜椒上西花蓟马的种群数量明显低于春季,也主要集中在花中取食.西花蓟马的天敌有瓢虫类、草蛉类和花蝽类,以花蝽类昆虫最多,并对西花蓟马种群具有一定的控制作用.%The dynamics of western flower thrips ( WFT) ( Frankliniella occidentalis ( Pergande ) ] and its natural enemies on plastic shed cultivation vegetables were investigated during spring and autumn seasons in Beijing. The results showed that the population grew slowly on sweet pepper planted in spring season during 30 days after transplanting. But the pest number increased rapidly with the emergence of flowering period and remained at a high level in June. The number of WFT in autumn season sweet pepper was obviously lower than that in spring. The pest preferred to feed in flowers. The observed natural enemies of WFT were ladybirds, lacewings and flower bugs, and the flower bug ( Orius spp.) was the dominant insect, which had some control effect to WFT.

  13. Behaviour of honey bees and bumble bees beneath three different greenhouse claddings

    OpenAIRE

    Blacquiere, T.; Aa-Furnée, van der, J.; Cornelissen, B; Donders, J.N.L.C.

    2006-01-01

    Several new cladding materials for greenhouses are tested and some already introduced in greenhouse horticulture, aiming at maximizing the transmission of photosynthetic radiation and reducing the loss of heat. As a part of the evaluation this research focuses on the suitability of different claddings for use in combination with pollinators. Pollinators, honeybees and bumblebees, are applied in a number of greenhouse vegetable and floricultural crops. In a commercial nursery and in small expe...

  14. Alternative Energy Sources and Energy Infrastructure for Dutch Greenhouses : Investigating Growers’ Preferences

    NARCIS (Netherlands)

    Araghi, Yashar; Dijkema, Gerard P.J.

    2015-01-01

    Growing plants, vegetables and flowers in greenhouses constitutes the core business and capability of the Dutch horticulture industry. Greenhouse owners in the Netherlands use advanced technology to maintain the quality of products and to remain competitive in international markets despite high cost

  15. Alternative Energy Sources and Energy Infrastructure for Dutch Greenhouses : Investigating Growers’ Preferences

    NARCIS (Netherlands)

    Araghi, Yashar; Dijkema, Gerard P.J.

    2015-01-01

    Growing plants, vegetables and flowers in greenhouses constitutes the core business and capability of the Dutch horticulture industry. Greenhouse owners in the Netherlands use advanced technology to maintain the quality of products and to remain competitive in international markets despite high cost

  16. Field based plastic contamination sensing

    Science.gov (United States)

    The United States has a long-held reputation of being a dependable source of high quality, contaminant-free cotton. Recently, increased incidence of plastic contamination from sources such as shopping bags, vegetable mulch, surface irrigation tubing, and module covers has threatened the reputation o...

  17. Horticultural production in greenhouses: efficient use of water

    NARCIS (Netherlands)

    Stanghellini, C.

    2014-01-01

    The central thesis of this paper is that greenhouse production of vegetables is the most water-efficient food production system and thus can contribute to meeting the challenge of feeding a better diet to an increasing world population, without increasing the need for irrigation water. The various

  18. Culture of the Tomato Micro-Tom Cultivar in Greenhouse.

    Science.gov (United States)

    Rothan, Christophe; Just, Daniel; Fernandez, Lucie; Atienza, Isabelle; Ballias, Patricia; Lemaire-Chamley, Martine

    2016-01-01

    Micro-Tom tomato cultivar is particularly adapted to the development of genomic approaches in tomato. Here, we describe the culture of this plant in greenhouse, including climate regulation, seed sowing and watering, vegetative development, plant maintenance, including treatment of phytosanitary problems, and reproductive development.

  19. Plastics Technology.

    Science.gov (United States)

    Barker, Tommy G.

    This curriculum guide is designed to assist junior high schools industrial arts teachers in planning new courses and revising existing courses in plastics technology. Addressed in the individual units of the guide are the following topics: introduction to production technology; history and development of plastics; safety; youth leadership,…

  20. Size and form of plots for the culture of the Italian pumpkin in plastic greenhouse Tamanho e forma de parcelas para a cultura da abóbora italiana cultivada em estufa plástica

    Directory of Open Access Journals (Sweden)

    Rodrigo Machado Mello

    2004-01-01

    Full Text Available Quality control is the guaranty that experimental error is kept under acceptable levels, and the definition of the proper size and form of experimental plots ensures acurate experimental planning. This paper aims to determine the proper plot size and shape for the culture of the Italian pumpkin in protected environments. Two experiments were set in plastic green house in distinct crop seasons: either Summer-Fall or Winter-Spring season. The experiment comprised eight, 23-m long lines with 20 plants each, and fruit weight was considered the main performance parameter. Estimates of best plots size and shape were obtained by the maximum curvature, variance comparison and Hatheway methods. The plot size and shape varied according to the season and the ideal size and shape, according to the maximum curvature and Hatheway methods, to the Summer-Fall and Winter-Spring seasons, were eight plants (4 ´ 2 plot and four plants (2 ´ 2 plot, respectively.Na experimentação é de fundamental importância o controle de qualidade, fazendo com que o erro experimental apresente-se em níveis aceitáveis e, uma das formas desse controle, é a definição do tamanho e forma ótimos de parcela, no planejamento experimental. Determinou-se o tamanho e a forma ideais de parcela, para a cultura da abóbora italiana, em experimentos realizados sob ambientes protegidos, avaliando-se o rendimento acumulado da fitomassa dos frutos. Foram conduzidos dois experimentos em estufa plástica, modelo arco pampeano, durante o ano de 2001, em duas épocas de cultivo, um na estação sazonal verão-outono e outro na estação sazonal inverno-primavera. Os experimentos foram constituídos de oito fileiras de 20m de comprimento, sendo que, em cada uma delas, foram alocadas 20 plantas. As estimativas do tamanho e da forma de parcela foram obtidas pelos métodos da máxima curvatura, da comparação das variâncias e de Hatheway. As estimativas do tamanho e da forma da parcela variaram

  1. Effects of soil conditioners on soil physical-chemical properties and yield and quality of vegetable in solar greenhouse%土壤调理剂对日光温室土壤理化性质和蔬菜产量、 品质的影响

    Institute of Scientific and Technical Information of China (English)

    廉晓娟; 路遥; 王艳; 梁鸣早; 杨军; 路森; 张余良; 王正祥

    2015-01-01

    The experiments were conducted to study the effects of soil conditioners on soil physical-chemical properties and yield and quality of vegetable in greenhouse. The results showed that soil conditioners obviously improved soil structure and soil retention capacity. Compared with the control treatment, when soil conditioners were applied twice, soil bulk density was reduced by 6. 36%, soil porosity was increased by 4. 97%, soil permeability coefficient was increased by 46. 28%, and soil field capacity was increased by 6. 75%. Soil conditioners also increased soil nutrient contents and improved the ability of soil fertility maintenance. And soil conditioners had improved yield and quality of vegetable, especially in quality of tomato. Co-application of soil conditioners and straw would obtain better effect.%试验研究了土壤调理剂对日光温室土壤理化性质和蔬菜产量、 品质的影响. 结果表明, 施用土壤调理剂能够明显改善土壤结构, 增强土壤保水能力, 与对照相比, 施用2次调理剂后土壤容重降低6. 36%, 土壤总孔隙度增加4. 97%, 田间持水量增加6. 75%, 渗透系数提高46. 28%; 调理剂还能增加土壤养分含量, 提高土壤保肥能力; 调理剂能够提高蔬菜的产量和品质, 对番茄品质的改善效果尤为明显; 调理剂与秸秆配合施用效果更佳.

  2. Hortisim: a model for greenhouse crops and greenhouse climate

    NARCIS (Netherlands)

    Gijzen, H.; Heuvelink, E.; Challa, H.; Dayan, E.; Marcelis, L.F.M.; Cohen, S.; Fuchs, M.

    1998-01-01

    A combined model for crop production and climate in greenhouses, HORTISIM, was developed. Existing models, developed by several research groups, of various aspects of crop growth and greenhouse climate have been integrated. HORTISIM contains 7 submodels (Weather, Greenhouse Climate, Soil, Crop, Gree

  3. LEDs for greenhouse lighting

    NARCIS (Netherlands)

    Nederhoff, E.M.

    2010-01-01

    Light Emitting Diodes (LED's) are a promising technology for greenhouse lighting with their efficiency to activate plant photosynthesis potentially higher in red LEDs than in HPS lamps. Due to their particular light colour, LEDs can initiate special effects in plants or steer plant processes and

  4. Innovation in greenhouse engineering

    NARCIS (Netherlands)

    Giacomelli, G.A.; Castilla, N.; Henten, van E.J.; Mears, D.R.; Sase, S.

    2008-01-01

    Innovations in greenhouse engineering are technical developments which help evolve the state-of-the-art in CEA (Controlled Environment Agriculture). They occur in response to the operational demands on the system, and to strategic changes in expectations of the production system. Influential

  5. Innovation in greenhouse engineering

    NARCIS (Netherlands)

    Giacomelli, G.A.; Castilla, N.; Henten, van E.J.; Mears, D.R.; Sase, S.

    2008-01-01

    Innovations in greenhouse engineering are technical developments which help evolve the state-of-the-art in CEA (Controlled Environment Agriculture). They occur in response to the operational demands on the system, and to strategic changes in expectations of the production system. Influential operati

  6. Smarter greenhouse climate control

    NARCIS (Netherlands)

    Nederhoff, E.M.; Houter, G.

    2011-01-01

    Greenhouse operators strive to be as economic as possible with energy. However, investing in fancy energy-saving equipment is often not cost-effective for smaller operations and in climate zones with mild winters. It is possible, though, for many growers to save energy without buying special equipme

  7. Greenhouse Gas Data Publication Tool

    Data.gov (United States)

    U.S. Environmental Protection Agency — This tool to gives you access to greenhouse gas data reported to EPA by large facilities and suppliers in the United States through EPA's Greenhouse Gas Reporting...

  8. Greenhouse production systems for people

    NARCIS (Netherlands)

    Giacomelli, G.A.; Sase, S.; Cramer, R.; Hoogeboom, J.; McKenzie, A.; Parbst, K.; Sacrascia-Mugnozza, G.; Selina, P.; Sharp, D.A.; Voogt, J.O.; Weel, van P.A.; Mears, D.

    2012-01-01

    Environmentally sound greenhouse production requires that: demand for market products is understood; greenhouse design addresses the climate circum-stances; input resources are available and consumed efficiently, and; there must be a reasonable balance of production products to the environmental

  9. Plastic bronchitis

    National Research Council Canada - National Science Library

    Singhi, Anil Kumar; Vinoth, Bharathi; Kuruvilla, Sarah; Sivakumar, Kothandam

    2015-01-01

    Plastic bronchitis, a rare but serious clinical condition, commonly seen after Fontan surgeries in children, may be a manifestation of suboptimal adaptation to the cavopulmonary circulation with unfavorable hemodynamics...

  10. Research on Cucumber Economical Irrigation Schedule and Irrigation Low Limit with Drip Irrigation Under Plastic Mulch in Greenhouse%温室膜下滴灌条件下黄瓜经济灌溉制度及其下限值的研究

    Institute of Scientific and Technical Information of China (English)

    郑志伟; 王仰仁; 汪绍盛; 赵宝永

    2016-01-01

    Taking the greenhouse cucumber with drip irrigation under plastic mulch as experimental material,three crop growth model parameters of the temperature,water stress index and dry matter transformation factor are determined,and the economic irrigation schedule is determined based on the three model parameters.The results show that:the economic irrigation system can significantly increase yield and income by 2.54 t/hm2 and 23 600 yuan/hm2 than the existing irrigation schedule,and the irrigation water con-sumption is saved by 7.59%.The fluctuation percent of soil moisture content (0~60 cm)before irrigation is much smaller than that of the crop growing period.The average value of soil water content before irrigation is used as the irrigation low limit for crop eco-nomical irrigation,and the value is 0.240.According to the irrigation low limit,the irrigation benefit of the unit area of Cucumber with drip irrigation under plastic mulch in Greenhouse can be the best.%以温室黄瓜为试验材料,采用膜下滴灌,对最适宜作物生长的温度、水分胁迫指数和干物质转化因子3个作物生长模型参数进行了率定,并以此为依据分析确定了膜下滴灌黄瓜的经济灌溉制度。结果表明:采用经济灌溉制度比实际灌水有显著的增产增收效果,产量和效益分别增加2.54 t/hm2和2.36万元/hm2,节约灌溉水量7.59%;在经济灌溉条件下灌水前土壤含水率(0~60 cm)随时间的变化幅度较作物生长期土壤含水率的变化幅度小得多,取各次灌水前土壤含水率的平均值作为作物经济灌溉的灌水下限值,对于本研究中的黄瓜,其值为0.240。按照该灌水下限值灌水,可使温室膜下滴灌黄瓜单位面积的灌溉效益最大。

  11. 海南大棚西瓜枯萎病病原菌生物学特性及室内毒力测定%Biological Characteristics and Toxicity Determination of Fusarium oxysporum f. sp. niveum on Watermelon Cultivated in Plastic Greenhouse in Hainan

    Institute of Scientific and Technical Information of China (English)

    范鸿雁; 周文静; 王祥和; 罗志文; 何凡

    2012-01-01

    fusarium wilt on watermelon cultivating in plastic greenhouse in Hainan was prepared. Keywords watermelon cultivated in plastic greenhouse in Hainan ; Fusarium oxysporum f. sp. niveum ; biological characteristics ; toxicity determination

  12. Plastic Fishes

    CERN Multimedia

    Trettnak, Wolfgang

    2015-01-01

    In terms of weight, the plastic pollution in the world’s oceans is estimated to be around 300,000 tonnes. This plastic comes from both land-based and ocean-based sources. A lecture at CERN by chemist Wolfgang Trettnak addressed this issue and highlighted the role of art in raising people’s awareness. The slideshow below gives you a taste of the artworks by Wolfgang Trettnak and Margarita Cimadevila.

  13. Plastic Bridge

    Institute of Scientific and Technical Information of China (English)

    履之

    1994-01-01

    Already ubiquitous in homes and cars, plastic is now appearing inbridges. An academic-industrial consortium based at the University ofCalifornia in San Diego is launching a three-year research program aimed atdeveloping the world’s first plastic highway bridge, a 450-foot span madeentirely from glass-,carbon,and polymer-fiber-reinforced composite mate-rials, the stuff of military aircraft. It will cross Interstate 5 to connect thetwo sides of the school’s campus.

  14. Analysis of residual characteristics of phthalate acid esters (PAEs) in vegetables from greenhouse vegetable production bases in Beijing%北京设施蔬菜基地蔬菜中邻苯二甲酸酯残留特征分析

    Institute of Scientific and Technical Information of China (English)

    陈佳祎; 李成; 栾云霞; 王纪华; 陆安祥

    2016-01-01

    目的:研究北京设施农业蔬菜中的邻苯二甲酸酯类(phthalic acid ester, PAEs)的污染水平,分析北京设施农业蔬菜中PAEs污染物特征。方法采集北京市昌平区、延庆区和顺义区的8个典型设施蔬菜基地16份蔬菜样品,利用超声提取、固相萃取柱净化、内标法定量,气相色谱质谱联用技术分析蔬菜中15种PAEs。结果在分析的蔬菜样品中均检测出PAEs,15种PAEs总浓度(∑PAEs)为0.15~6.94 mg/kg,平均含量为4.91 mg/kg。蔬菜中PAEs的单体分布相似,其中以邻苯二甲酸(2-乙基)己酯(DEHP)含量最高,占∑PAEs的36.9%,邻苯二甲酸二丁酯(DBP)和邻苯二甲酸二异丁酯(DIBP)含量次之,分别占∑PAEs的33.5%和19.2%。结论设施蔬菜基地地膜的使用导致PAEs存在于各类蔬菜,蔬菜中的PAEs残留量应引起重视。%Objective To study the pollution level of phthalic acid ester (PAEs) and analyze the pollution characteristics in vegetables of facility vegetable base. Methods The 16 vegetable samples were collected from 8 typical vegetable production bases located in Changping, Yanqing and Shunyi District. Fifteen kinds of PAEs were analyzed through ultrasonic extraction, solid phase extraction column purification, isotope internal standard quantization and gas chromatography-mass spectrometry. Results PAEs were ubiquitous contaminants in vegetables, and total PAE concentrations ranged from 0.15 to 6.94 mg/kg, with the average content of 4.91 mg/kg in the vegetable samples. The distribution of PAEs monomer in various vegetables was similar. The concentration of bis (2-ethylhexyl) phthalate was the highest, followed by dibutyl phthalate and diisobutyl phthalate. The proportion of bis (2-ethylhexyl) phthalate, dibutyl phthalate and diisobutyl phthalate in PAEs was 36.9%, 33.5% and 19.2%, respectively. Conclution The residual value of PAEs in vegetables deserves more attention due to widely application of film in facility vegetable base.

  15. GREEN PLASTIC: A NEW PLASTIC FOR PACKAGING

    OpenAIRE

    Mr. Pankaj Kumar*, Sonia

    2016-01-01

    This paper gives a brief idea about a new type of plastic called as bio-plastic or green plastic. Plastic is used as a packaging material for various products, but this plastic is made up of non renewable raw materials. There are various disadvantages of using conventional plastic like littering, CO2 production, non-degradable in nature etc. To overcome these problems a new type of plastic is discovered called bio-plastic or green plastic. Bio-plastic is made from renewable resources and also...

  16. An Introduction to Greenhouse Production. Second Edition.

    Science.gov (United States)

    McMahon, Robert W.

    This student manual is presented in its first revision, providing a current, basic text for those preparing for greenhouse and floriculture work. Its fourteen chapters are: Overview of the Greenhouse Industry; Greenhouse Structures; Controlling the Greenhouse Environment; Greenhouse Equipment and Lighting; Greenhouse Irrigation Systems; Root Media…

  17. Greenhouse Warming Research

    DEFF Research Database (Denmark)

    Sørensen, Bent Erik

    2016-01-01

    The changing greenhouse effect caused by natural and anthropogenic causes is explained and efforts to model the behavior of the near-surface constituents of the Earth's land, ocean and atmosphere are discussed. Emissions of various substances and other aspects of human activity influence the gree......The changing greenhouse effect caused by natural and anthropogenic causes is explained and efforts to model the behavior of the near-surface constituents of the Earth's land, ocean and atmosphere are discussed. Emissions of various substances and other aspects of human activity influence...... the greenhouse warming, and the impacts of the warming may again impact the wellbeing of human societies. Thus physical modeling of the near-surface ocean-soil-atmosphere system cannot be carried out without an idea of the development of human activities, which is done by scenario analysis. The interactive...... nature of the natural and the human system calls for an extremely complex analysis, in order to predict the outcome of various proposed changes in human behavior. This includes halting activities that most influence the climate and finding workable alternatives to these activities, or adapting to climate...

  18. Experimental Analysis of Open, Simple and Modified Greenhouse Dryers for Drying Potato Flakes Under Forced Convection

    Directory of Open Access Journals (Sweden)

    Tanuj Kumar Sahu

    2016-07-01

    Full Text Available Drying using burning of fossil fuels and open sun drying are traditional way to dry crops, fruits, vegetables etc. But there are some disadvantages associated with them such as crops are affected by dirt and other impurities. To overcome the problems associated with open sun drying and drying using burning of fossil fuels, solar greenhouse drying is found out to be the best alternative. In present work the performance of simple and modified greenhouse dryer is evaluated and effort is made to increase the drying rate of greenhouse dryer which has been achieved in modified greenhouse dryer with inclined roof. Total weight of potato flakes was reduced by 80.1 % in modified greenhouse dryer in just 5 hours whereas it took 6 hours in simple greenhouse dryer for achieving nearly same values.

  19. Plastic condoms.

    Science.gov (United States)

    1968-01-01

    Only simple equipment, simple technology and low initial capital investment are needed in their manufacture. The condoms can be made by people who were previously unskilled or only semi-skilled workers. Plastic condoms differ from those made of latex rubber in that the nature of the plastic film allows unlimited shelf-life. Also, the plastic has a higher degree of lubricity than latex rubber; if there is a demand for extra lubrication in a particular market, this can be provided. Because the plastic is inert, these condoms need not be packaged in hermetically sealed containers. All these attributes make it possible to put these condoms on the distributors' shelves in developing countries competitively with rubber condoms. The shape of the plastic condom is based on that of the lamb caecum, which has long been used as luxury-type condom. The plastic condom is made from plastic film (ethylene ethyl acrilate) of 0.001 inch (0.0254 mm.) thickness. In addition, a rubber ring is provided and sealed into the base of the condom for retention during coitus. The advantage of the plastic condom design and the equipment on which it is made is that production can be carried out either in labour-intensive economy or with varying degrees of mechanization and automation. The uniform, finished condom if made using previously untrained workers. Training of workers can be done in a matter of hours on the two machines which are needed to produce and test the condoms. The plastic film is provided on a double wound roll, and condom blanks are prepared by means of a heat-sealing die on the stamping machine. The rubber rings are united to the condom blanks on an assembly machine, which consists of a mandrel and heat-sealing equipment to seal the rubber ring to the base of the condom. Built into the assembly machine is a simple air-testing apparatus that can detect the smallest pinhole flaw in a condom. The manufacturing process is completed by unravelling the condom from the assembly

  20. Plastic Bronchitis.

    Science.gov (United States)

    Rubin, Bruce K

    2016-09-01

    Plastic bronchitis is an uncommon and probably underrecognized disorder, diagnosed by the expectoration or bronchoscopic removal of firm, cohesive, branching casts. It should not be confused with purulent mucous plugging of the airway as seen in patients with cystic fibrosis or bronchiectasis. Few medications have been shown to be effective and some are now recognized as potentially harmful. Current research directions in plastic bronchitis research include understanding the genetics of lymphatic development and maldevelopment, determining how abnormal lymphatic malformations contribute to cast formation, and developing new treatments. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Addition of ash on drained forested peatlands in southern Sweden. Effects on forest production, fluxes of greenhouse gases, peat properties, understorey vegetation and groundwater chemistry; Tillfoersel av aska i skog paa dikad torvmark i soedra Sverige. Effekter paa skogsproduktion, floeden av vaexthusgaser, torvegenskaper, markvegetation och grundvattenkemi

    Energy Technology Data Exchange (ETDEWEB)

    Sikstroem, Ulf; Bjoerk, Robert G.; Ring, Eva; Ernfors, Maria; Jacobson, Staffan; Nilsson, Mats; Klemedtsson, Leif

    2009-02-15

    The objective of the present study was to evaluate effects of wood-ash addition on drained peatlands in southern Sweden. Tree growth, greenhouse gases, peat properties, microbial biomass and processes, understory vegetation and groundwater chemistry were measured in three field experiments (some variables were not measured in all experiments): (i) 168 Perstorp, an oligotrophic mire with Scotch pine (Pinus sylvestris L.), where 2.5 tonnes d.w. of wood ash/ha (2.5WA) was added in 1982; (ii) 273 Anderstorp, also an oligotrophic mire with Scots pine, where 3.3 tonnes d.w. crushed ash/ha (3.3KA) and 6.6 tonnes d.w. crushed/ha (6.6KA) was added in 2003; (iii) 278 Skogaryd, a minerotrophic mire with Norway spruce (Picea abies L. Karst.), where the same doses of crushed ash as in Anderstorp were added in 2006. Untreated controls were included in all experiments. At Anderstorp, increased tree growth was indicated, at least in the treatment with the highest ash dose during the first five years after treatment. The annual emissions of CO{sub 2}, CH4 and N{sub 2}O from the peat were unaffected. At Skogaryd, the growth was unaffected and the emissions of both CO{sub 2} and N{sub 2}O were reduced during the first two years after treatment. In general, the significant ash effects (2.5WA and 3.3KA evaluated) on peat characteristics, microbial biomass and processes were found in the upper soil (0-5 cm) at the recently treated sites (Anderstorp and Skogaryd), and at greater depths (5-30 cm) at Perstorp, where the ash was added 25 years ago. In the ash treatment at Perstorp, there was a shift in the plant community structure and a decrease in species diversity of the understory vegetation. However, at this point of time, the forest stand had become substantially denser than on the control plots. Hence, these effects on the understory vegetation may have been an indirect effect of the ash-induced altered tree stand properties. In Skogaryd, no shift in the plant community was found

  2. Presettlement Vegetation

    Data.gov (United States)

    Minnesota Department of Natural Resources — Presettlement vegetation of Minnesota based on Marschner's original analysis of Public Land Survey notes and landscape patterns. Marschner compiled his results in...

  3. Mixed plastics recycling technology

    CERN Document Server

    Hegberg, Bruce

    1995-01-01

    Presents an overview of mixed plastics recycling technology. In addition, it characterizes mixed plastics wastes and describes collection methods, costs, and markets for reprocessed plastics products.

  4. The greenhouse effect

    DEFF Research Database (Denmark)

    Laut, Peter; Gundermann, Jesper

    1992-01-01

    a convincing basis for decision making in order to counter climatic change will become evere more acute. Even though most governments may agree that something should be done, many disagree over the extent, the pace, and the acceptable costs of action. Is it, for example, sufficient to follow the recommendation...... of the 1988 conference in Toronto on "The Changing Atmosphere" and reduce global CO2 emissions by 20% until year 2005, or is it vital for the future of the World to reduce emissions at a much quicker pace? And how do we compare reductions of different greenhouse gases by different amounts, implemented over...

  5. Plastic fish

    CERN Multimedia

    Antonella Del Rosso

    2015-01-01

    In terms of weight, the plastic pollution in the world’s oceans is estimated to be around 300,000 tonnes. This plastic comes from both land-based and ocean-based sources. A lecture at CERN by chemist Wolfgang Trettnak addressed this issue and highlighted the role of art in raising people’s awareness.   Artwork by Wolfgang Trettnak. Packaging materials, consumer goods (shoes, kids’ toys, etc.), leftovers from fishing and aquaculture activities… our oceans and beaches are full of plastic litter. Most of the debris from beaches is plastic bottles. “PET bottles have high durability and stability,” explains Wolfgang Trettnak, a chemist by education and artist from Austria, who gave a lecture on this topic organised by the Staff Association at CERN on 26 May. “PET degrades very slowly and the estimated lifetime of a bottle is 450 years.” In addition to the beach litter accumulated from human use, rivers bring several ki...

  6. Plastic zonnecellen

    NARCIS (Netherlands)

    Roggen, Marjolein

    1998-01-01

    De zonnecel van de toekomst is in de maak. Onderzoekers van uiteenlopend pluimage werken eendrachtig aan een plastic zonnecel. De basis is technisch gelegd met een optimale, door invallend licht veroorzaakte, vorming van ladingdragers binnen een composiet van polymeren en buckyballs. Nu is het zaak

  7. Limits and prospects of photovoltaic covers in Mediterranean greenhouses

    Directory of Open Access Journals (Sweden)

    Alvaro Marucci

    2013-06-01

    Full Text Available The use of plastic film coverings has made a significant contribution to the development of greenhouses in Italy and to a new generation of greenhouses that differ from those of Central and Northern Europe: the so called Mediterranean Greenhouse. This is a simple structure with cheap coverings and emergency artificial heating systems. During the winter season, the available solar energy is more than sufficient to meet energy requirements. During the hot season, however, the intense solar radiation and the high air temperatures are problematic. Different active and passive strategies are, therefore, used to counteract this excessive energy intake with a considerable increase in costs. We believe that using this surplus energy to produce electricity would: i provide an income from the sale of electricity; ii allow the greenhouse to be used throughout the year; iii reduce the costs of cooling the greenhouse. This paper aims to identify the energy surplus in relation to cultivation requirements that could be used to produce electricity with new and innovative solutions based on flexible and semi-transparent photovoltaic modules. The research was carried out with reference to the southern coast of the Lazio region, central Italy, by evaluating energy supply and demand to determine the surplus of solar energy produced in a greenhouse covered with double plastic film. Besides the shape of the greenhouse, the surplus depends on the covering material and the location. The degree of cloud cover and the type of cultivation carried out in the greenhouse also have an impact. We calculated the surplus energy under extreme conditions: clear sky and cloudy sky, and according to different crop species (tomato 12 months, tomato 8 months, aubergine 12 months. Results showed: i the surplus of energy available in the greenhouse for the production of energy from new generation solar cells with varying degrees of sky coverage and crop species; ii the times of the year

  8. Vegetables Business Opportunities in Ghana: 2014

    NARCIS (Netherlands)

    Saavedra Gonzalez, Y.R.; Dijkxhoorn, Y.; Elings, A.; Glover-Tay, J.; Koomen, I.; Maden, van der E.C.L.J.; Nkansah, G.; Obeng, P.

    2014-01-01

    This report addresses the current performance, overall business climate of the vegetable sector and tries to come up with a number of business opportunities. These include business opportunities for high-quality exports, greenhouse technology, and healthy food for the domestic market. It equally

  9. Vegetables Business Opportunities in Ghana: 2014

    NARCIS (Netherlands)

    Saavedra Gonzalez, Y.R.; Dijkxhoorn, Y.; Elings, A.; Glover-Tay, J.; Koomen, I.; Maden, van der E.C.L.J.; Nkansah, G.; Obeng, P.

    2014-01-01

    This report addresses the current performance, overall business climate of the vegetable sector and tries to come up with a number of business opportunities. These include business opportunities for high-quality exports, greenhouse technology, and healthy food for the domestic market. It equally adv

  10. OPIC Greenhouse Gas Emissions Inventory

    Data.gov (United States)

    Overseas Private Investment Corporation — Independent analysis details quantifying the greenhouse gas ("GHG") emissions directly attributable to projects to which the Overseas Private Investment Corporation...

  11. 灌溉方法和整枝方式对塑料大棚西红柿农艺性状的影响%Influences of Different Irriagtion Methods and Pruning Patterns on Agronomic Properties of Tomato in Plastic Greenhouse

    Institute of Scientific and Technical Information of China (English)

    李浩霞; 王峰; 杜建明; 郭永忠; 王东清

    2013-01-01

    The results of influences of different irriagtion methods and pruning patterns on agronomic properties of tomato in plastic greenhouse showed that different pruning methods and irrigation patterns had great influence on agronomic traits of tomato ′Xiuyu′. The plant height by hanging vines pruning significantly decreased than hanging vines and the head fall pruning ,and drop about 25.3%,but the quantity of layer of fruits by the latter pruning had more 5 layers than that by the former training ,and the output increased 13.90%~23.58%,and extended the time to market 26 d.We could make saving on water throught drip irrigation nearly more 1/2 than throught furrow irrigation ,and more than 76 kg/m3 in the water use effici-ency. The plant growth,the fruit weight and the output could significantly improve in the conditions of hanging vine head fall pruning and drip irrigation.%灌溉方法和整枝方式对塑料大棚西红柿农艺性状的影响试验研究结果表明,不同的整枝方式和灌溉方法对秀玉西红柿植株农艺性状影响较大,采用吊蔓单干整枝植株高度明显比吊蔓换头落蔓整枝植株低,降幅约为25.3%;吊蔓换头落蔓整枝比吊蔓单干整枝结果层数多出5层,增产在13.90%~23.58%,延长上市时间26 d。滴灌比沟灌节约用水近1/2,且水分利用率在76 kg/m3以上。秀玉西红柿在吊蔓换头落蔓整枝+滴灌条件下,能明显提高植株生长势、单果重和总产量,有效节约用水。

  12. Plastic Surgery Statistics

    Science.gov (United States)

    ... PSN PSEN GRAFT Contact Us News Plastic Surgery Statistics Plastic surgery procedural statistics from the American Society of Plastic Surgeons. Statistics by Year Print 2016 Plastic Surgery Statistics 2015 ...

  13. Materials for luminescent greenhouse solar collectors.

    Science.gov (United States)

    Levitt, J A; Weber, W H

    1977-10-01

    Luminescent greenhouse solar collectors are potentially useful for concentrating sunlight onto photovoltaic power cells. Measurements of the performance of small-scale collectors made of two commercially available materials (Owens-Illinois ED2 neodymium-doped laser glass and rhodamine 6G-doped plastic) are presented. The results are encouraging, but they indicate a need for further spectral sensitization and for reduced matrix loss coefficient. The measurements with monochromatic illumination agree with the predictions of a mathematical model developed to take account of reemission following the absorption of luminescence. Under solar illumination, the model predicts photon flux concentrations of about 15 for optimized full-scale collectors made of the materials studied and concentrations of 110 for reasonably improved glass.

  14. Plastic bronchitis

    Directory of Open Access Journals (Sweden)

    Anil Kumar Singhi

    2015-01-01

    Full Text Available Plastic bronchitis, a rare but serious clinical condition, commonly seen after Fontan surgeries in children, may be a manifestation of suboptimal adaptation to the cavopulmonary circulation with unfavorable hemodynamics. They are ominous with poor prognosis. Sometimes, infection or airway reactivity may provoke cast bronchitis as a two-step insult on a vulnerable vascular bed. In such instances, aggressive management leads to longer survival. This report of cast bronchitis discusses its current understanding.

  15. Has your greenhouse gone virtual?

    Science.gov (United States)

    Virtual Grower is a free decision-support software program available from USDA-ARS that allows growers to build a virtual greenhouse. It was initially designed to help greenhouse growers estimate heating costs and conduct simple simulations to figure out where heat savings could be achieved. Featu...

  16. Turkish tomato greenhouse gets geothermal heating

    NARCIS (Netherlands)

    Sikkema, A.; Maaswinkel, R.H.M.

    2011-01-01

    Wageningen UR Greenhouse Horticulture will set up an ultramodern greenhouse in Turkey, together with Dutch greenhouse builders and contractors. Geothermal energy will be used there to provide heat and carbon dioxide for tomato cultivation.

  17. VEGETABLE GROWING - HOBBY AND BENEFIT FOR AGED PERSON HEALTH

    Directory of Open Access Journals (Sweden)

    Scurtu Ion

    2015-07-01

    Full Text Available Vegetable growing in small areas (open field, plastic tunnels, unheated or heated green house or even in balcony may be a very pleasant activity for many old persons who want to preserve their physical and mental health. Beside many common vegetable species like tomatoes, pepper, eggplant, onion, garlic, cabbage, cucumber, lettuce and so on - can be cultivated in small areas many others vegetables like broccoli, Brussels cabbage, Scorzonera hispanica, asparagus, Witloof Chicory (French endive and vegetable with medicinal properties.

  18. Kuchler Vegetation

    Data.gov (United States)

    California Department of Resources — Digital version of potential natural plant communites as compiled and published on 'Map of the Natural Vegetation of California' by A. W. Kuchler, 1976. Source map...

  19. Wieslander Vegetation

    Data.gov (United States)

    California Department of Resources — Digital version of the 1945 California Vegetation Type Maps by A. E. Wieslander of the U.S. Forest Service. Source scale of maps are 1:100,000. These compiled maps...

  20. Design of Low Cost Greenhouse Monitoring using ZigBee Technology

    Directory of Open Access Journals (Sweden)

    A. Salleh

    2013-09-01

    Full Text Available —Greenhouses are often used for growing flowers, vegetables, fruits, and tobacco plants. Most greenhouse systems still use the manual system in monitoring the temperature and humidity in the greenhouse, a lot of problems can occur not for worker but also affected production rate because the temperature and humidity of the greenhouse must be constantly monitored to ensure optimal conditions. The Wireless Sensor Network (WSNcan be used to gather the data from point to point to trace down the local climate parameters in different parts of the big greenhouse to make the greenhouse automation system work properly. This paper presents the design of low costgreenhouse monitoring system to monitor a greenhouse temperature and humidity parameters by applying the ZigBee technology as the WSN system. During the design process, Peripheral Interface Controller (PIC, LCD Display and Zigbee as the main hardware components is used as hardware components while C compiler and MP Lab IDE were used for software elements. The data from the greenhouse was measured by the sensor then the data will be displayed on the LCD screen on the receiver which support up to 100 m range. By using this system, the process of monitoring is easier and it also cheaper for installation and maintenance. The feasibility of the developed node was tested by deploying a simple sensor network into the Agriculture Department of Melaka Tengah greenhouse in Malaysia.

  1. A RESEARCH ON VENTILATION EFFICIENCY OF PIPED VENTILATION SYSTEMS IN GEOTHERMALLY HEATED GREENHOUSES

    Directory of Open Access Journals (Sweden)

    İbrahim Örüng

    2016-07-01

    Full Text Available Greenhouse play significant roles in human nutrition. Vegetable and fruit consumption at certain amounts is the basic pre-condition for a well nutrition. It is possible to produce sufficient quantities of fruits and vegetables in places with available climate conditions. However, fruits and vegetables should be grown in special buildings to have a year-long production in places without available climate conditions. These places include under-cover production facilities, greenhouses, low and high tunnel facilities. Environmental conditions are adjusted are adjusted in greenhouses as to provide proper conditions for plant growth and development. Ventilation is used to remove excess heat, moisture and carbon dioxide from the greenhouses. Either natural or mechanical ventilation is used in greenhouses. Mechanical ventilation systems have various advantages over natural systems. However, mostly natural ventilation systems are preferred because of their low installation and operational costs. Both systems operates based on negative pressure. Air exchange rates are usually low in winters and it is quite hard to evenly distribute cold fresh air within the greenhouse. Air inlets are usually placed over side walls and outlets are commonly placed along the ridge. In this study an alternative natural ventilation system was proposed for more efficient ventilation of the greenhouses. In this system, fresh air gets into the greenhouse through ventilation pipes installed beneath the greenhouse floor. The incoming fresh air also heated with geothermal hot water lines, thus direct contact of cold fresh air is prevented. The design and efficiency of piped ventilation systems were provided in this paper.

  2. System for monitoring microclimate conditions in greenhouse

    Directory of Open Access Journals (Sweden)

    Marković Dušan B.

    2014-01-01

    Full Text Available Monitoring microclimate parameters in different kind of environments has significant contribution to many areas of human activity and production processes. One of them is vegetable production in greenhouses where measurement of its microclimate parameters may influence the decision on taking appropriate action and protect crops. It is also important to preserve optimal condition in greenhouses to facilitate the process of transpiration, plant mineral nutrition and prevent of a variety physiological damage caused by a deficit of some specific nutrients. Systems for monitoring have wide application in the last years thanks to development of modern computer technology. In this paper model of the monitoring system based on smart transducer concept was introduced. Within the system components are based on MSP430 ultra low power micro controllers. They are using wireless communication to exchange data within the system that was structured according to smart transducer concept. User applications from the network could access to system interface using HTTP protocol where web server could be running on the computer or it could be an embedded web server running on micro controller based device.

  3. Pathogenicity of Two Species of Entomopathogenic Nematodes Against the Greenhouse Whitefly, Trialeurodes vaporariorum (Hemiptera: Aleyrodidae), in Laboratory and Greenhouse Experiments.

    Science.gov (United States)

    Rezaei, Nastaran; Karimi, Javad; Hosseini, Mojtaba; Goldani, Morteza; Campos-Herrera, Raquel

    2015-03-01

    The greenhouse whitefly Trialeurodes vaporariorum (Hemiptera: Aleyrodidae) is a polyphagous pest in greenhouse crops. The efficacy of two entomopathogenic nematodes (EPN), Steinernema feltiae and Heterorhabditis bacteriophora, as biological control agents against T. vaporariorum was evaluated using two model crops typical of vegetable greenhouse productions: cucumber and pepper. Laboratory tests evaluated adults and second nymphal instars for pest susceptibility to different EPN species at different concentrations of infective juveniles (IJ; 0, 25, 50, 100, 150, 200, and 250 IJ per cm(2)); subsequent greenhouse trials against second nymphal instars on cucumber and pepper plants evaluated more natural conditions. Concentrations were applied in combination with Triton X-100 (0.1% v/v), an adjuvant for increasing nematode activity. In laboratory studies, both life stages were susceptible to infection by the two nematode species, but S. feltiae recorded a lower LC50 than H. bacteriophora for both insect stages. Similarly, in greenhouse experiments, S. feltiae required lower concentrations of IJ than H. bacteriophora to reach the same mortality in nymphs. In greenhouse trials, a significant difference was observed in the triple interaction among nematode species × concentration × plant. Furthermore, the highest mortality rate of the second nymphal instars of the T. vaporariorum was obtained from the application of S. feltiae concentrated to 250 IJ/cm(2) on cucumber (49 ± 1.23%). The general mortality caused by nematodes was significantly higher in cucumber than in pepper. These promising results support further investigation for the optimization of the best EPN species/concentration in combination with insecticides or adjuvants to reach a profitable control of this greenhouse pest.

  4. Evapotranspiração máxima da cultura de pimentão em estufa plástica em função da radiação solar, da temperatura, da umidade relativa e do déficit de saturação do ar Maximum evapotranspiration of sweet pepper in plastic greenhouse as a function of solar radiation, temperature, relative humidity and water vapor pressure deficit of the air

    Directory of Open Access Journals (Sweden)

    Genei Antonio Dalmago

    2006-06-01

    Full Text Available Um experimento foi conduzido para avaliar a relação da evapotranspiração máxima (ETm da cultura de pimentão por unidade de índice de área foliar (ETmf com a radiação solar global incidente (Rg e e saldo de radiação (Rn e, externos à estufa, e com a temperatura (t am, umidade relativa (URm e déficit de saturação (D do ar no interior da estufa. A ETm foi determinada por lisimetria. Apenas a temperatura e a umidade relativa do ar foram registradas e as demais variáveis foram estimadas. O Rn e apresentou o maior efeito isolado, seguido pelo D e pela URm. A temperatura do ar às 15 horas e a temperatura máxima diária foram as variáveis pontuais de maior associação com a ETmf. A Rg e melhorou sua relação quando analisada em diferentes faixas de t am. Os resultados confirmaram o Rn e e o D como as variáveis meteorológicas de maior efeito preditivo da evapotranspiração das culturas em estufas plásticas no outono, porém com graus diferenciados de ajuste para o pimentão em relação às outras culturas.An experiment was carried out to study the relationship between sweet pepper maximum evapotranspiration (ETm per unit leaf area index (ETmf and incident solar radiation (Rg e and net radiation (Rn e outside greenhouse, and with air temperature (t am, air relative humidity (URm and water vapor pressure deficit (D inside a greenhouse. ETm was measured by lysimeters. Temperature and relative humidity were registered whereas Rg e and Rn e were estimated. The Rn e was the variable with laRg e st effect on ETmf determination, followed by D and URm. The air temperature at 15:00 and the daily maximum temperature were variables of laRg e r association with ETmf among the variables with punctual time observations. Rg e improved its relationship with ETmf when was analyzed with different t am ranges. The results confirmed Rn e and D as the meteorological variables of highest relationship with evapotranspiration in plastic greenhouse

  5. 土壤改良剂施用对设施土壤微生物数量与酶活性及青菜生长的影响%Effects of soil conditioners on the soil microbial biomass and enzyme activities and the growth of green vegetables in greenhouse

    Institute of Scientific and Technical Information of China (English)

    陆利民; 赵晶; 杨业凤; 邵婷; 周艳孔; 胡晓颖; 沈源源

    2016-01-01

    Two kinds of soil conditioners(loose soil and Trichoderma)with different concentrations were applied in greenhouse to study the effect of them on the soil microbial biomass and enzyme activities.The results showed that after application of loose soil,the number of bacteria and actinomycetes increased significantly,the total microbial biomass increased,the total number of soil fungi had no significant change in continuous cropping soil;after application of Trichoderma,the number of bacteria,actinomycetes and fungi increased,and the total amount of microorganism increased in continuous cropping soil.Both soil conditioners improved the activity of urease,neutral phosphatase,invertase,cellulase and catalase.Both soil conditioners were all in favor of root growth of green vegetables,and the growth and yield significantly increased.%在设施大棚中分别施用不同浓度的两种土壤改良剂———松壤与木霉菌剂,研究其对土壤微生物数量与酶活性的影响。结果表明:施用松壤后,连作土壤细菌与放线菌数量显著增加,微生物总量增加,土壤真菌总数无显著变化;施用木霉菌剂后,连作土壤细菌、放线菌及真菌数量增加,微生物总量增加。两种土壤改良剂施用均提高了脲酶、中性磷酸酶、蔗糖酶、纤维素酶、过氧化氢酶活性。此外,施用两种土壤改良剂均有利于青菜植株根系生长,设施青菜的长势和产量明显提高。

  6. (Limiting the greenhouse effect)

    Energy Technology Data Exchange (ETDEWEB)

    Rayner, S.

    1991-01-07

    Traveler attended the Dahlem Research Conference organized by the Freien Universitat, Berlin. The subject of the conference was Limiting the Greenhouse Effect: Options for Controlling Atmospheric CO{sub 2} Accumulation. Like all Dahlem workshops, this was a meeting of scientific experts, although the disciplines represented were broader than usual, ranging across anthropology, economics, international relations, forestry, engineering, and atmospheric chemistry. Participation by scientists from developing countries was limited. The conference was divided into four multidisciplinary working groups. Traveler acted as moderator for Group 3 which examined the question What knowledge is required to tackle the principal social and institutional barriers to reducing CO{sub 2} emissions'' The working rapporteur was Jesse Ausubel of Rockefeller University. Other working groups examined the economic costs, benefits, and technical feasibility of options to reduce emissions per unit of energy service; the options for reducing energy use per unit of GNP; and the significant of linkage between strategies to reduce CO{sub 2} emissions and other goals. Draft reports of the working groups are appended. Overall, the conference identified a number of important research needs in all four areas. It may prove particularly important in bringing the social and institutional research needs relevant to climate change closer to the forefront of the scientific and policy communities than hitherto.

  7. Terrestrial transect study on driving mechanism of vegetation changes

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In terms of Chinese climate-vegetation model based on the classification of plant functional types, to- gether with climatic data from 1951 to 1980 and two future climatic scenarios (SRES-A2 and SRES-B2) in China from the highest and the lowest emission scenarios of greenhouse gases, the distribution patterns of vegetation types and their changes along the Northeast China Transect (NECT) and the North-South Transect of Eastern China (NSTEC) were simulated in order to understand the driving mechanisms of vegetation changes under climatic change. The results indicated that the vegetation distribution patterns would change significantly under future climate, and the major factors driving the vegetation changes were water and heat. However, the responses of various vegetation types to the changes in water and heat factors were obviously different. The vegetation changes were more sensi- tive to heat factors than to water factors. Thus, in the future climate warming will significantly affect vegetation distribution patterns.

  8. VEGETATION MAPPING IN WETLANDS

    Directory of Open Access Journals (Sweden)

    F. PEDROTTI

    2004-01-01

    Full Text Available The current work examines the main aspects of wetland vegetation mapping, which can be summarized as analysis of the ecological-vegetational (ecotone gradients; vegetation complexes; relationships between vegetation distribution and geomorphology; vegetation of the hydrographic basin lo which the wetland in question belongs; vegetation monitoring with help of four vegetation maps: phytosociological map of the real and potential vegetation, map of vegetation dynamical tendencies, map of vegetation series.

  9. 有机无机肥料配合施用对日光温室土壤氨挥发的影响%Effects of Combined Application of Organic Manure and Chemical Fertilizers on Ammonia Volatilization from Greenhouse Vegetable Soil

    Institute of Scientific and Technical Information of China (English)

    郝小雨; 高伟; 王玉军; 金继运; 黄绍文; 唐继伟; 张志强

    2012-01-01

    [Objective] Excessive use of chemical nitrogen fertilizers suffer from nitrogen loss through ammonia (NH3) volatilization, resulting in decreasing effectiveness of the fertilizers and increasing the risk of environmental pollution. Less information is available on the effect of different fertilization patterns on NH3 volatilization from greenhouse vegetable soils. Based on balanced fertilization and optimized irrigation, this study was conducted to determine the effect of combined application of organic manure and chemical fertilizers on NH3 volatilization. [ Method J A field experiment was designed to study the dynamics of NH3 volatilization by the venting method under celery-tomato rotation system in Tianjin from September 2010 to June 2011. The field experiment consisted of six treatments of 1 (No N), 2 (4/4 CN+0/4 PN, all nitrogen in chemical fertilizer, PN denotes nitrogen in pig manure), 3 (3/4 CN+1/4 PN), 4 (2/4 CN+2/4 PN), 5 (2/4 CN+2/4 SN, SN denotes nitrogen in straw), and 6 (CF, conventional fertilization). Equal NPK was designed for treatments 2, 3, 4, and 5. Rates of P2O5 and K2O application were respectively equal for each of treatments 1, 2, 3, 4 and 5. [Result] The peak of NH3 volatilization rate occurred within 2-3 days after basal fertilization,whereas in first day after fertilizer top-dressing (fertilization and irrigation were carried out simultaneously) during the celery and tomato growth period. The NH3 volatilization rate from the nitrogen application treatment closed to the rate from the no nitrogen application treatment until first 8-10 days after basal fertilization and first 10-11 days after fertilizer top-dressing, respectively. 70%-80% of total NH3 volatilization during celery or tomato growth period were from over the first 10 days after basal fertilization to the first 11 days after the second fertilizer top-dressing. Distinct total NH3 volatilization during tomato growth period with higher temperature was found, with the total

  10. Solar detoxification plant for a hazardous plastic bottle recycling plant in El Ejido: feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Blanco, J.; Malato, S. [CIEMAT, Plataforma Solar de Almeria (PSA), Tabernas (Spain); Richter, C. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V., Koeln (Germany)

    1997-12-31

    The removal of persistent organic chemicals from water is a pressing ecological problem. Persistent contaminants, such as pesticides, solvents, detergents and a variety of industrial chemicals, are capable of deep penetration into the soil and reach groundwater due to combination of chemical stability, resistance to biodegradation and sufficient water solubility. The Spanish province of Almeria has experienced an important economical growth during the last 20 years due to the installation of a large number of greenhouses, which benefit from the extremely sunny climate for production of vegetables and fruits. Unfortunately, this development is accompanied by an intensive use of a wide variety of pesticides with the subsequent problem of empty plastic bottles. Unitl now these plaguicide containers have usually been burnt or buried. Since the problem has been growing in the last years, a parallel environmental consciousness has been rising in the region concerning the recycling of these pesticide bottles; this process includes washing of the shredded plastic containers, which gives rise to relatively small quantities of water contaminated with toxic and persistent compounds at a concentration level of some hundred mg/l of total organic carbon content. This appears to be a very promising application for TiO{sub 2} - Solar Photocatalytic Detoxification, which provides an adequate solution as there is no clear alternative way to solve the problem. (orig.)

  11. Greenhouses and their humanizing synergies

    Science.gov (United States)

    Haeuplik-Meusburger, Sandra; Paterson, Carrie; Schubert, Daniel; Zabel, Paul

    2014-03-01

    Greenhouses in space will require advanced technical systems of automatic watering, soil-less cultivation, artificial lighting, and computerized observation of plants. Functions discussed for plants in space habitats include physical/health requirements and human psychology, social cohesion, as well as the complex sensorial benefits of plants for humans. The authors consider the role of plants in long-term space missions historically since 1971 (Salyut 1) and propose a set of priorities to be considered within the design requirements for greenhouses and constructed environments given a range of benefits associated with plant-human relationships. They cite recent research into the use of greenhouses in extreme environments to reveal the relative importance of greenhouses for people living in isolated locations. Additionally, they put forward hypotheses about where greenhouses might factor into several strata of human health. In a recent design-in-use study of astronauts' experiences in space habitats discussed in Architecture for Astronauts (Springer Press 2011) it was found that besides the basic advantages for life support there are clearly additional "side benefits" for habitability and physical wellbeing, and thus long-term mission success. The authors have composed several key theses regarding the need to promote plant-human relationships in space, including areas where synergy and symbiosis occur. They cite new comprehensive research into the early US Space Program to reveal where programmatic requirements could be added to space architecture to increase the less quantifiable benefits to astronauts of art, recreation, and poetic engagement with their existential condition of estrangement from the planet. Specifically in terms of the technological requirements, the authors propose the integration of a new greenhouse subsystem component into space greenhouses—the Mobile Plant Cultivation Subsystem—a portable, personal greenhouse that can be integrated

  12. Greenhouse Earth: A Traveling Exhibition

    Energy Technology Data Exchange (ETDEWEB)

    Booth, W.H.; Caesar, S.

    1992-09-01

    The Franklin Institute Science Museum provided an exhibit entitled the Greenhouse Earth: A Traveling Exhibition. This 3500 square-foot exhibit on global climate change was developed in collaboration with the Association of Science-Technology Centers. The exhibit opened at The Franklin Institute on February 14, 1992, welcoming 291,000 visitors over its three-month stay. During its three-year tour, Greenhouse Earth will travel to ten US cities, reaching two million visitors. Greenhouse Earth aims to deepen public understanding of the scientific issues of global warming and the conservation measures that can be taken to slow its effects. The exhibit features hands-on exhibitry, interactive computer programs and videos, a theater production, a demonstration cart,'' guided tours, and lectures. supplemental educational programs at the Institute included a teachers preview, a symposium on climate change, and a satellite field trip.'' The development of Greenhouse Earth included front-end and formative evaluation procedures. Evaluation includes interviews with visitors, prototypes, and summative surveys for participating museums. During its stay in Philadelphia, Greenhouse Earth was covered by the local and national press, with reviews in print and broadcast media. Greenhouse Earth is the first large-scale museum exhibit to address global climate change.

  13. Overcoming maladaptive plasticity through plastic compensation

    Directory of Open Access Journals (Sweden)

    Matthew R.J. MORRIS, Sean M. ROGERS

    2013-08-01

    Full Text Available Most species evolve within fluctuating environments, and have developed adaptations to meet the challenges posed by environmental heterogeneity. One such adaptation is phenotypic plasticity, or the ability of a single genotype to produce multiple environmentally-induced phenotypes. Yet, not all plasticity is adaptive. Despite the renewed interest in adaptive phenotypic plasticity and its consequences for evolution, much less is known about maladaptive plasticity. However, maladaptive plasticity is likely an important driver of phenotypic similarity among populations living in different environments. This paper traces four strategies for overcoming maladaptive plasticity that result in phenotypic similarity, two of which involve genetic changes (standing genetic variation, genetic compensation and two of which do not (standing epigenetic variation, plastic compensation. Plastic compensation is defined as adaptive plasticity overcoming maladaptive plasticity. In particular, plastic compensation may increase the likelihood of genetic compensation by facilitating population persistence. We provide key terms to disentangle these aspects of phenotypic plasticity and introduce examples to reinforce the potential importance of plastic compensation for understanding evolutionary change [Current Zoology 59 (4: 526–536, 2013].

  14. Overcoming maladaptive plasticity through plastic compensation

    Institute of Scientific and Technical Information of China (English)

    Matthew R.J.MORRIS; Sean M.ROGERS

    2013-01-01

    Most species evolve within fluctuating environments,and have developed adaptations to meet the challenges posed by environmental heterogeneity.One such adaptation is phenotypic plasticity,or the ability of a single genotype to produce multiple environmentally-induced phenotypes.Yet,not all plasticity is adaptive.Despite the renewed interest in adaptive phenotypic plasticity and its consequences for evolution,much less is known about maladaptive plasticity.However,maladaptive plasticity is likely an important driver of phenotypic similarity among populations living in different environments.This paper traces four strategies for overcoming maladaptive plasticity that result in phenotypic similarity,two of which involve genetic changes (standing genetic variation,genetic compensation) and two of which do not (standing epigenetic variation,plastic compensation).Plastic compensation is defined as adaptive plasticity overcoming maladaptive plasticity.In particular,plastic compensation may increase the likelihood of genetic compensation by facilitating population persistence.We provide key terms to disentangle these aspects of phenotypic plasticity and introduce examples to reinforce the potential importance of plastic compensation for understanding evolutionary change.

  15. Tomato and cowpea crop evapotranspiration in an unheated greenhouse

    Institute of Scientific and Technical Information of China (English)

    Xu Junzeng; Peng Shizhang; Luo Yufeng; Jiao Xiyun

    2008-01-01

    With the development of protected cultivation of vegetables in China, it is necessary to study the water requirements of crops in greenhouses. Lysimeter experiments were carried out to investigate tomato (2001) and cowpea (2004) crop evapotranspiration (ETc) in an unheated greenhouse in Eastern China. Results showed remarkably reduced crop evapotranspiration inside the greenhouse as compared with that outside. ETc increased with the growth of the crops, and varied in accordance with the temperature inside the greenhouse and 20-cm pan evaporation outside, reaching its maximum value at the stage when plants' growth was most active. Differences between the variation of crop evapotranspiration and pan evaporation inside the greenhouse were caused by shading of the pan in the later period when the crops were taller than the location where the pan was installed, 70 cm above ground. The ratio of crop evapotranspiration to pan evaporation was not constant as reported in previous studies, and the variation of the inside ratio αin lagged behind that of the outside ratio αout. Simulation of crop evapotranspiration based on 20-cm pan evaporation inside the greenhouse is more reasonable than that based on 20-cm pan evaporation outside, although pan evaporation outside is more consistent with ETc than that inside. The value of αin, calculated based on air temperature, relative humidity, and ground temperature inside, plays a dominant role in the calculation of ETc. As the crop height increases, altering the location of the inside pan and placing it above the canopy, out of the shade, would help to achieve more reasonable values of crop evapotranspiration.

  16. Tomato and cowpea crop evapotranspiration in an unheated greenhouse

    Directory of Open Access Journals (Sweden)

    Xu Junzeng

    2008-06-01

    Full Text Available With the development of protected cultivation of vegetables in China, it is necessary to study the water requirements of crops in greenhouses. Lysimeter experiments were carried out to investigate tomato (2001 and cowpea (2004 crop evapotranspiration (ETc in an unheated greenhouse in Eastern China. Results showed remarkably reduced crop evapotranspiration inside the greenhouse as compared with that outside. ETc increased with the growth of the crops, and varied in accordance with the temperature inside the greenhouse and 20-cm pan evaporation outside, reaching its maximum value at the stage when plants’ growth was most active. Differences between the variation of crop evapotranspiration and pan evaporation inside the greenhouse were caused by shading of the pan in the later period when the crops were taller than the location where the pan was installed, 70 cm above ground. The ratio of crop evapotranspiration to pan evaporation was not constant as reported in previous studies, and the variation of the inside ratio αin lagged behind that of the outside ratio αout. Simulation of crop evapotranspiration based on 20-cm pan evaporation inside the greenhouse is more reasonable than that based on 20-cm pan evaporation outside, although pan evaporation outside is more consistent with ETc than that inside. The value of αin, calculated based on air temperature, relative humidity, and ground temperature inside, plays a dominant role in the calculation of ETc. As the crop height increases, altering the location of the inside pan and placing it above the canopy, out of the shade, would help to achieve more reasonable values of crop evapotranspiration.

  17. General Vegetation

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This file contains vector digital data for vegetation groupings in New Mexico at a 1:1,000,000 scale. The source software was ARC/INFO 5.0.1 and the conversion...

  18. Recycling of Plastic

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Fruergaard, Thilde

    2011-01-01

    Plastic is produced from fossil oil. Plastic is used for many different products. Some plastic products like, for example, wrapping foil, bags and disposable containers for food and beverage have very short lifetimes and thus constitute a major fraction of most waste. Other plastic products like......, good strength and long durability. Recycling of plastic waste from production is well-established, while recycling of postconsumer plastic waste still is in its infancy. This chapter describes briefly how plastic is produced and how waste plastic is recycled in the industry. Quality requirements...

  19. Characteristics of WWTP sludge after drying in greenhouse for agricultural purposes.

    Science.gov (United States)

    Lima, Márcia Regina Pereira; Zandonade, Eliana; Sobrinho, Pedro Alem

    2012-01-01

    The sludge generated by sewage treatment which meets regulatory standards can be used in agriculture. With this understanding, the focus of this study is the evaluation of the agricultural characteristics and inorganic substances in excess activated sludge, which was subjected to drying in a greenhouse. The variables (factor) evaluated during the drying process were: type of sludge (digested or not digested), addition of lime to the sludge, and the physical layout and rotation of sludge in the greenhouse. The parameters monitored for this assessment were moisture, volatile solids and pH. The greenhouse cover and sides were made of translucent plastic to allow the penetration of solar radiation and prevent water from entering. A impermeable floor was used. The sludge was generated in sewage treatment plants located in the metropolitan region of Grande Vitória, Espírito Santo, Brazil. The solar drying of wastewater sludge in a greenhouse presented satisfactory results.

  20. The Greenhouse and Anti-Greenhouse Effects on Titan

    Science.gov (United States)

    McKay, C. P.; Cuzzi, Jeffrey N. (Technical Monitor)

    1994-01-01

    Titan is the largest moon of Saturn and is the only moon in the solar system with a substantial atmosphere. Its atmosphere is mostly made of nitrogen, with a few percent CH4, 0.1% H2 and an uncertain level of Ar (less than 10%). The surface pressure is 1.5 atms and the surface temperature is 95 K, decreasing to 71 at the tropopause before rising to stratospheric temperatures of 180 K. In pressure and composition Titan's atmosphere is the closest twin to Earth's. The surface of Titan remains unknown, hidden by the thick smog layer, but it may be an ocean of liquid methane and ethane. Titan's atmosphere has a greenhouse effect which is much stronger than the Earth's - 92% of the surface warming is due to greenhouse radiation. However an organic smog layer in the upper atmosphere produces an anti-greenhouse effect that cuts the greenhouse warming in half - removing 35% of the incoming solar radiation. Models suggest that during its formation Titan's atmosphere was heated to high temperatures due to accretional energy. This was followed by a cold Triton-like period which gradually warmed to the present conditions. The coupled greenhouse and haze anti-greenhouse may be relevant to recent suggestions for haze shielding of a CH4 - NH3 early atmosphere on Earth or Mars. When the NASA/ESA mission to the Saturn System, Cassini, launches in a few years it will carry a probe that will be sent to the surface of Titan and show us this world that is strange and yet in many ways similar to our own.

  1. Growing Substrate Composition Influences Growth, Productivity and Quality of Organic Vegetables

    OpenAIRE

    Narayana Bhat; Mohammed Albaho; Majda Suleiman; Binson Thomas; Preetha George; Sasini Isath Ali

    2013-01-01

    Organic food production, a dynamic and rapidly growing global activity is still new to Kuwait. Therefore, investigations were conducted during 2006-09 to develop package of cultivation practices for producing organic greenhouse vegetables under Kuwait’s environmental conditions. One of the objectives of these investigations was to select a suitable growing substrate for organic greenhouse vegetable production. A number of combinations of vermicompost, cocopeat, sphagnum peatmoss, perlite, far...

  2. Influência do plástico branco, poda verde e amino quelant®-K na qualidade de pêssegos 'Santa Áurea' Influence of white plastic, vegetative pruning and amino quelant-K on quality of peaches 'Santa Àurea'

    Directory of Open Access Journals (Sweden)

    Renato Trevisan

    2008-01-01

    Full Text Available A qualidade das frutas é determinada por fatores relacionados ao clima, solo, cultivar, as práticas culturais adotadas, época e forma de colheita e processos de manipulação da fruta na pós-colheita. Uma das formas de melhorar esta qualidade é a utilização de práticas de manejo na pré-colheita. Assim, este trabalho teve por objetivo avaliar o efeito do plástico branco, da poda verde e do nutriente aminoquelant®-K, associado ou não ao tratamento com plástico branco e poda verde, na qualidade de pêssegos 'Santa Áurea'. Os atributos de qualidade avaliados foram: percentagem visual de vermelho, intensidade de vermelho na epiderme, determinada pelo sistema CIEL*a*b*, massa, diâmetro, firmeza de polpa, sólidos solúveis totais (SST, acidez total titulável (ATT e relação SST/ATT. As práticas utilizadas causaram o aumento do percentual de vermelho na epiderme das frutas; o aminoquelant®-K isolado proporcionou maior acidez das frutas; a melhor relação SST/ATT foi obtida com o uso do plástico branco sob a copa e pela combinação do plástico com o nutriente aminoquelant®-K.Fruit quality is influenced by climate, soil, cultivar, orchard management, time of harvesting and fruit handling at harvest and post harvest. One way of improving the fruit quality is through cultural practices. Thus, this work had the objective of evaluating the effect of the white plastic, vegetative pruning and aminoquelant®-K, alone or the combination of the last with plastic or summer pruning, on the quality of peaches cv. Santa Aurea. The quality attributes evaluated quality were: visual percentage of red on the fruit surface, intensity of red in the epidermis, determined by the CIEL*a*b * system, fruit mean weight, diameter and firmness, total soluble solids (TSS content on the flesh, total titratable acidity (TTA and the relation TSS/TTA. All the tested treatments increased the percentage of red on the fruit epidermis; the use of aminoquelant

  3. Phenotypic plasticity of two varieties of Poa pratensis in vegetation concrete%两种早熟禾品种在植被砼上的表型可塑性

    Institute of Scientific and Technical Information of China (English)

    费永俊; 刘志雄; 武平

    2006-01-01

    研究了2个早熟禾(poa pratensis)品种Nublue、Kenblue建植在植被砼和田园土的表型可塑性(phenotypic plasticity).结果表明:从叶长、叶宽、株高、基部直径4个方面相比较,Kenblue在植被砼与田园土上表现出显著的差异;但植被砼上Nublue与田园土上的比较,除叶长、叶宽、株高3个方面表现了显著的差异外,其基径并没有表现出显著的差异.就成坪性的综合指标而言,建植在植被砼上的Nublue要好于植被砼上的Kenblue.

  4. 河西走廊有机生态型无土栽培在设施蔬菜辣椒生产中的应用%Application of organic ecotype soilless culturing in greenhouse vegetable production of capsicum annuum in Hexi Corridor

    Institute of Scientific and Technical Information of China (English)

    郭治; 丁亮

    2016-01-01

    A completely randomized design was implemented to investigate the effects of organic cultural substrate compositions on the growth ,yield and fruit quality of Capsicum annuum in sunlight greenhouse with treatments including mushroom residue (A ) ,mushroom residue ,peat and corn stalks (B ) ,mushroom residue ,corn stalks and cinder (C ) , perlite and cinder (D) ,Vpeat∶Vcinder =3∶2 (CK1 ) as the control for soilless cultural substrate ,and soil cultivation (CK2 ) as the control for cultivation mode .The results indicated that the treatment B (mushroom residue ,peat and corn stalks) on the growth of C .annuum was the best among all treatments ,which significantly increased the plant height by 16 .6% and 11 .0% ,stem diameter by 24 .2% and 18 .8% ,fruit-setting number per plant by 5 .8 and 3 .6 ,yield per plant by 0 .67 kg and 0 .31 kg ,and plot yield by 9 .4 kg and 7 .2 kg ,from CK1 and CK2 respectively .Additionally ,the effect of treatment C (mushroom residue ,corn stalks and cinder) was the second-best ,which significantly increased the plant height by 19 .6% and 24 .5% ,and plot yield by 6 .0 kg .and 3 .8 kg ,from CK1 and CK2 respectively .Moreover , the treatments of B and C significantly improved the fruit quality of C .annuum ,and the treatment B significantly in-creased the Vc content by 48 .5% and 13 .5% ,soluble protein content by 23 .3% and 10 .9% ,and reducing suger con-tent by 27 .7% and 12 .2% , and the treatment C significantly increased the organic acid content by 16 .4% and 10 .6% ,and soluble saccharide content by 14 .3% and 10 .0% ,from CK1 and CK2 respectively .The results showed that the treatments of mushroom residue ,peat and corn stalks (B ) ,and mushroom residue ,corn stalks and cinder (C ) significantly promoted the growth of C .annuum and improved its fruits quality ,which may be suitable for popularization and application in culturing greenhouse solanaceous vegetables .%试验采用完全随机区组设计,设置处理A:纯菇渣

  5. Spatial analysis of climate factors used to determine suitability of greenhouse production in Turkey

    Science.gov (United States)

    Cemek, Bilal; Güler, Mustafa; Arslan, Hakan

    2017-04-01

    This study aimed to identify the most suitable growing periods for greenhouse production in Turkey in order to make valuable contribution to economic viability. Data collected from the meteorological databases of 81 provinces was used to determine periodic climatological requirements of greenhouses in terms of cooling, heating, natural ventilation, and lighting. Spatial distributions of mean daily outside temperatures and greenhouse heating requirements were derived using ordinary co-kriging (OCK) supported by Geographical Information System (GIS). Mean monthly temperatures throughout the country were found to decrease below 12 °C in January, February, March, and December, indicating heating requirements, whereas temperatures in 94.46 % of the country rose above 22 °C in July, indicating cooling requirements. Artificial lighting is not a requirement in Turkey except for November, December, and January. The Mediterranean, Aegean, Marmara, and Black Sea Regions are more advantageous than the Central, East, and Southeast Anatolia Regions in terms of greenhouse production because the Mediterranean and Aegean Regions are more advantageous in terms of heating, and the Black Sea Region is more advantageous in terms of cooling. Results of our study indicated that greenhouse cultivation of winter vegetables is possible in certain areas in the north of the country. Moreover, greenhouses could alternatively be used for drying fruits and vegetables during the summer period which requires uneconomical cooling systems due to high temperatures in the Mediterranean and Southeastern Anatolian Regions.

  6. componente vegetal

    Directory of Open Access Journals (Sweden)

    Fabio Moscovich

    2005-01-01

    Full Text Available In order to determine environmental impact, indicators based on vegetation characteristics that would generate the forestry monoculture with the adjacent native forest, 32 sample unit were installed in an area of LIPSIA private enterprise, Esperanza Department, Misiones with those characteristics. The plots of 100 m2 were distributed systematically every 25 meters. The vegetation was divided in stratum: superior (DBH ≥ 10 cm, middle (1,6 cm ≤ DBH > 10 cm and inferior (DBH< cm. There were installed 10 plots in a logged native forest, 10 plots in a 18 years old Pinus elliottii Engelm. with approximately 400 trees/ha., 6 plots in a 10 – 25 years old Araucaria angustifolia (Bertd. Kuntze limiting area with approximately 900 trees/ha., and 6 plots located in this plantation. In the studied area were identified 150 vegetation species. In the inferior stratum there were found differences as function of various floristic diversity indexes. In all the cases the native forest showed larger diversity than plantations, followed by Pinus elliottii, Araucaria plantation and Araucaria limiting area. All the studied forest fitted to a logarithmical series of species distributions, that would indicate the incidence of a environmental factor in this distribution.

  7. An environmental systems analysis of greenhouse horticulture in the Netherlands - the tomato case

    NARCIS (Netherlands)

    Pluimers, J.C.

    2001-01-01

    Objective of the thesisThe greenhouse horticulture sector in the Netherlands covers about 10,000 hectares and produces vegetables, cut flowers and pot plants. This agricultural sector is of social and economic importance because of its annual production value, export earnings and th

  8. Geothermal heating systems for greenhouses

    Energy Technology Data Exchange (ETDEWEB)

    Silva, J.F.; Johnson, W.C.

    1980-08-12

    Ways to utilize low-temperature geothermally heated water for a flow-through system are presented. The geothermal energy used for this system is the waste heat discharged from space heating 500,000 square feet of floor space at Oregon Institute of Technology with geothermal water pumped directly from the campus wells. The information collected and analyzed is from data developed from operating a greenhouse on the Oregon Institute of Technology campus from December 1979 to April 1980. Methods for calculating heating requirements of greenhouses using geothermal energy were developed from the analyses of the data obtained. (MHR)

  9. Determinants of recycling common types of plastic product waste in environmental horticulture industry: The case of Georgia.

    Science.gov (United States)

    Meng, Ting; Klepacka, Anna M; Florkowski, Wojciech J; Braman, Kristine

    2016-02-01

    Environmental horticulture firms provide a variety of commercial/residential landscape products and services encompassing ornamental plant production, design, installation, and maintenance. The companies generate tons of waste including plastic containers, trays, and greenhouse/field covers, creating the need to reduce and utilize plastic waste. Based on survey data collected in Georgia in 2013, this paper investigates determinants of the environmental horticulture firms' recycling decision (plastic containers, flats, and greenhouse poly). Our findings indicate that the decision to discard vs. recycle plastic containers, flats, and greenhouse poly is significantly influenced by firm scope, size, location, and partnership with recycling providers, as well as whether recycling providers offer additional waste pickup services. Insights from this study are of use to local governments and environmental organizations interested in increasing horticultural firm participation in recycling programs and lowering the volume of plastic destined for landfills.

  10. DEVELOPMENT OF GREENHOUSE CULTIVATION AND ITS PROBLEMS IN T.R.N.C.

    Directory of Open Access Journals (Sweden)

    Güven ŞAHİN

    2011-12-01

    Full Text Available Today, malnutrition that is caused by the rapidly increasing global population became one of the problems worldwide. Additionally, serious health problems that are caused by GMOs are the great concerns of the countries. Therefore, researchers from different fields are trying to find a variety solutions to this problem. Thus, greenhouse cultivation holds importance as an alternative agricultural method. In fact, historically greenhouse cultivation goes up until Roman Empire, and it has been developed in recent years. Greenhouse cultivation had started as an avocation or a leisure activity of only rich people. However, it expanded to a broader range of population to enable farming of some fruits and vegetables at their unnatural habitats or seasons. In this study, alterations of these processes since the day of establishment were analyzed. Greenhouse cultivation in T.R.N.C. in the content of agricultural geography has been evaluated because of its convenient conditions due to its duration of sunlight achievement and localization.

  11. 陕西云阳蔬菜大棚土壤养分及微生物群落功能多样性研究%Effects of Planting Years on Soil Nutrients and Microbial Functional Diversity in Vegetable Plastic Tunnel in Yunyang, Shaanxi, China

    Institute of Scientific and Technical Information of China (English)

    李玉娣; 谷洁; 付青霞; 钱勋; 杨玖; 高华; 王小娟; 朱创江

    2014-01-01

    Soil environmental quality greatly influences vegetable quality and safety as well as economic benefit in the vegetable production under plastic tunnel. This study investigated changes of soil physical-chemical properties and microbial community function in different planting years(0 a, 5 a, 10 a, 20 a)of cucumber/tomato under plastic tunnel at Yunyang town in Shaanxi Province of China. Results showed that soil electrical conductivity(EC), total nitrogen, total phosphorus, available nutrient and organic matter contents were the high-est in the 10 a planting soils, being increased by 17.7% to 326.6%, compared with the control soil(0 a). However, these indexes were 15.2% to 41.6% lower in 20 a soils than in 10 a soils. The ability of soil microbes to utilize carbon sources was also highest in the 10 a old soils. The average well color development(AWCD), Shannon, Simpson, and McIntosh indexes were significantly higher in 10 a than in soils of the other years. Carbohydrate and amino acids were the main carbon sources for soil microbes. Our results suggest that 10 a planting may be the best growth years for production of vegetable plastic tunnels in this area.%为了探讨蔬菜大棚种植年限对土壤养分和微生态环境的影响,以陕西省泾阳县云阳镇0(大田土壤)、5、10 a 和20 a 棚龄土壤为研究对象,对不同年限蔬菜大棚土壤养分和微生物群落功能多样性进行研究。结果表明:随着种植年限增加,土壤电导率、全氮、全磷、速效养分和有机质含量均先升高后降低;10 a 棚龄土壤的微生物群落碳源利用能力最强,土壤微生物群落的 AWCD 值、Shannon、Simpson、McIntosh 和丰富度指数均显著高于其他种植年限,20 a 棚龄土壤微生物群落碳源利用能力和微生物总体活性降低,仅高于0 a 棚龄土壤。主成分分析结果显示,10、20 a 和0 a 棚龄土壤微生物群落碳源利用能力存在显著差异,起分异作用的

  12. Irrigation management in organic greenhouse

    NARCIS (Netherlands)

    Voogt, W.; Balendonck, J.; Berkelmans, R.; Enthoven, N.

    2017-01-01

    Irrigation in protected cultivation is essential due to the absence of natural precipitation. High evapotranspiration, due to higher temperature and prolonged cropping period, requires ample an adequate supply of water. The water supply in a greenhouse is solely carried out by irrigation and thus

  13. The Living Rainforest Sustainable Greenhouses

    NARCIS (Netherlands)

    Bot, G.P.A.; Zwart, de H.F.; Hansen, K.; Logan, A.; Witte Groenholland, H.

    2008-01-01

    The Living Rainforest (www.livingrainforest.org) is an educational charity that uses rainforest ecology as a metaphor for communicating general sustainability issues to the public. Its greenhouses and office buildings are to be renovated using the most sustainable methods currently available. This w

  14. Identification of Forest Vegetation Using Vegetation Indices

    Institute of Scientific and Technical Information of China (English)

    Yuan Jinguo; Wang Wei

    2004-01-01

    Spectral feature of forest vegetation with remote sensing techniques is the research topic all over the world, because forest plays an important role in human beings' living environment. Research on vegetation classification with vegetation index is still very little recently. This paper proposes a method of identifying forest types based on vegetation indices,because the contrast of absorbing red waveband with reflecting near-infrared waveband strongly for different vegetation types is recognized as the theoretic basis of vegetation analysis with remote sensing. Vegetation index is highly related to leaf area index, absorbed photosynthetically active radiation and vegetation cover. Vegetation index reflects photosynthesis intensity of plants and manifests different forest types. According to reflectance data of forest canopy and soil line equation NIR=1.506R+0.0076 in Jingyuetan, Changchun of China, many vegetation indices are calculated and analyzed. The result shows that the relationships between vegetation indices and forest types are that perpendicular vegetation index (PVI) identifies broadleaf forest and coniferous forest the most easily;the next is transformed soil-adjusted vegetation index(TSVI) and modified soil-adjusted vegetation index(MSVI), but their calculation is complex. Ratio vegetation index (RVT) values of different coniferous forest vary obviously, so RVI can classify conifers.Therefore, the combination of PVI and RVI is evaluated to classify different vegetation types.

  15. Vegetation Map and Vegetation Monographs of China

    Institute of Scientific and Technical Information of China (English)

    GUO Ke

    2010-01-01

    @@ Vegetation Map of China As the most significant component of an ecosystem,vegetation plays the most important role in maintaining biodiversity and providing the necessary resources for human beings.A vegetation map shows the major vegetation types of a region and their geographic distribution patterns.

  16. The development and cultivation of tomatillo (Physalis ixocarpa Brot. under the climatic conditions of Poland. I. Local cultivars, growth of aboveground vegetative parts, probable resistance to Phytophthora infestans

    Directory of Open Access Journals (Sweden)

    Leszek S. Jankiewicz

    2013-12-01

    Full Text Available Tomatillo (Physalis ixocarpa Brot. grows in Poland much like in Mexico although its development cycle is much longer and lasts 6 months. It was sown at the beginning of April in a heated greenhouse, and transferred later on to a heated plastic tunnel. It was transplanted to a field about May 20 when danger of frosts had passed. Three local cultivars of Mexican origin were used and are briefly described. Their vegetative growth characteristics in Poland were similar to that of cv. Rendidora, which was described earlier in Mexico. The tomatillo internodes and leaves became progressively smaller with age. Tomatillo leaves and fruits were not attacked by Phytophthora infestans in the field and laboratory. Inoculation with tomato strains of this disease was without effect.

  17. The Greenhouse Effect: Science and Policy.

    Science.gov (United States)

    Schneider, Stephen H.

    1989-01-01

    Discusses many of the scientific questions surrounding the greenhouse effect debate and the issue of plausible responses. Discussion includes topics concerning projecting emissions and greenhouse gas concentrations, estimating global climatic response, economic, social, and political impacts, and policy responses. (RT)

  18. Building and using the solar greenhouse

    Energy Technology Data Exchange (ETDEWEB)

    None

    1983-01-01

    Thorough directions are given for planning, constructing and using a solar greenhouse attached to a house. Included is a method of calculating the savings accruing from the use of the greenhouse. (LEW)

  19. Accounting for Greenhouse Gas Emissions from Reservoirs

    Science.gov (United States)

    Nearly three decades of research has demonstrated that the impoundment of rivers and the flooding of terrestrial ecosystems behind dams can increase rates of greenhouse gas emission, particularly methane. The 2006 IPCC Guidelines for National Greenhouse Gas Inventories includes ...

  20. Accounting for Greenhouse Gas Emissions from Reservoirs

    Science.gov (United States)

    Nearly three decades of research has demonstrated that the impoundment of rivers and the flooding of terrestrial ecosystems behind dams can increase rates of greenhouse gas emission, particularly methane. The 2006 IPCC Guidelines for National Greenhouse Gas Inventories includes ...

  1. Recycling of Plastic

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Fruergaard, Thilde

    2011-01-01

    Plastic is produced from fossil oil. Plastic is used for many different products. Some plastic products like, for example, wrapping foil, bags and disposable containers for food and beverage have very short lifetimes and thus constitute a major fraction of most waste. Other plastic products like......, for example, gutters, window frames, car parts and transportation boxes have long lifetimes and thus appear as waste only many years after they have been introduced on the market. Plastic is constantly being used for new products because of its attractive material properties: relatively cheap, easy to form......, good strength and long durability. Recycling of plastic waste from production is well-established, while recycling of postconsumer plastic waste still is in its infancy. This chapter describes briefly how plastic is produced and how waste plastic is recycled in the industry. Quality requirements...

  2. The effect on climate change impacts for building products when including the timing of greenhouse gas emissions

    Science.gov (United States)

    Richard D Bergman

    2012-01-01

    Greenhouse gases (GHGs) trap infrared radiation emitting from the Earth’s surface to generate the “greenhouse effect” thus keeping the planet warm. Many natural activities including rotting vegetation emit GHGs such as carbon dioxide to produce this natural affect. However, in the last 200 years or so, human activity has increased the atmospheric concentrations of GHGs...

  3. Engineering concepts for inflatable Mars surface greenhouses.

    Science.gov (United States)

    Hublitz, I; Henninger, D L; Drake, B G; Eckart, P

    2004-01-01

    A major challenge of designing a bioregenerative life support system for Mars is the reduction of the mass, volume, power, thermal and crew-time requirements. Structural mass of the greenhouse could be saved by operating the greenhouse at low atmospheric pressure. This paper investigates the feasibility of this concept. The method of equivalent system mass is used to compare greenhouses operated at high atmospheric pressure to greenhouses operated at low pressure for three different lighting methods: natural, artificial and hybrid lighting.

  4. Climate design of vegetable oil fuels. Mathematical model for the calculation and optimization of greenhouse gas emission saving using vegetable oil as a fuel especially in agricultural machinery in accordance with the fuel quality directive 2009/30/EG; Klimadesign von Pflanzenoelkraftstoffen. Mathematisches Modell fuer die Berechnung und Optimierung der Treibhausgasemissionseinsparung durch den Einsatz von Pflanzenoel als Kraftstoff insbesondere in Landwirtschaftsmaschinen in Uebereinstimmung mit der Kraftstoffqualitaetsrichtlinie 2009/30/EG

    Energy Technology Data Exchange (ETDEWEB)

    Stoehr, Michael [Bundesdeutscher Arbeitskreis fuer Umweltbewusstes Management e.V., B.A.U.M., Muenchen (Germany); Pickel, Peter [John Deere European Technology Innovation Center, Kaiserslautern (Germany)

    2012-07-01

    The use of biofuels in agricultural machinery is an option to respond to climate requirements. This option is being imposed from the European Commission to manufacturers of mobile machines. The contribution under consideration formulates a mathematical model that implements the regulations of the EU Fuel Quality Directive for complex manufacturing processes in the calculation rules. Initially, this model was tested and verified by the example of the standard manufacturing process of pure rapeseed oil. Then, possibilities of optimization for the production of rapeseed oil are explored. Finally, the mathematical model was applied to the calculation of greenhouse gas emissions from camelina oil from mixed cultivation with wheat.

  5. Using waste oil to heat a greenhouse

    Science.gov (United States)

    Marla Schwartz

    2009-01-01

    During the winter of 1990, Northwoods Nursery (Elk River, ID) purchased a wood-burning system to heat the current greenhouses. This system burned slabs of wood to heat water that was then pumped into the greenhouses. The winter of 1990 was extremely harsh, requiring non-stop operation of the heating system. In order to keep seedlings in the greenhouse from freezing,...

  6. The Greenhouse Effect and Built Environment Education.

    Science.gov (United States)

    Greenall Gough, Annette; Gough, Noel

    The greenhouse effect has always existed. Without the greenhouse effect, Earth could well have the oven-like environment of Venus or the deep-freeze environment of Mars. There is some debate about how much the Earth's surface temperature will rise given a certain amount of increase in the amount of greenhouse gases such as carbon dioxide, nitrous…

  7. Plant nutrition in future greenhouse production

    NARCIS (Netherlands)

    Sonneveld, C.; Voogt, W.

    2009-01-01

    In the introduction chapter it was claimed that greenhouse production has no longer arguments as a supply market. The products of the greenhouse industry became in free competition with those from field production from all over the world. In this competition the greenhouse industry has developed int

  8. Greenhouse gas flux dynamics in wetlands

    Energy Technology Data Exchange (ETDEWEB)

    Silvola, J.; Alm, J.; Saarnio, S. [Joensuu Univ. (Finland). Dept. of Biology; Martikainen, P.J. [National Public Health Inst., Kuopio (Finland). Dept. of Environmental Microbiology

    1996-12-31

    Two important greenhouse gases, CO{sub 2} and CH{sub 4}, are closely connected to the carbon cycling of wetlands. Although virgin wetlands are mostly carbon accumulating ecosystems, major proportion of the CO{sub 2} bound annually in photosynthesis is released back to the atmosphere. Main portion of the carbon cycling in wetlands is quite fast while a small proportion of carbon diffusing from soil is released from organic matter, which may be ten thousand years old. Methane is formed in the anaerobic layers of wetlands, from where it is released gradually to the atmosphere. The decomposition in anaerobic conditions is very slow, which means that usually only a few percent of the annual carbon cycling takes place as methane. Research on CO{sub 2} fluxes of different virgin and managed peatlands was the main topic of this project during the first phase of SILMU. The measurements were made during two seasons in varying conditions in c. 30 study sites. In the second phase of SILMU the research topics were the spatial and temporal variation of CO{sub 2} and CH{sub 4} fluxes, the relationships between vegetation and gas fluxes as well as carbon balance studies in wetlands at some intensive sites

  9. The Storage Ability Of Lamb’S Lettuce Cultivated In The Greenhouse Under Led Or Hps Lamps

    Directory of Open Access Journals (Sweden)

    Kołton Anna

    2014-12-01

    Full Text Available Leafy vegetables are the source of many valuable components like vitamins, minerals and phenolic compounds as antioxidants. Chlorophyll derivatives have antioxidant and anticarcinogenic activity, or may even act as signalling molecules in organisms. However, during the storage of the leafy vegetables in the cold and darkness, numerous biochemical changes usually occurs, demonstrated as the breakdown of chlorophyll. Storage ability of plants depends to some extent on the conditions under which plants grew. Lamb’s lettuce plants were grown in the greenhouse in different light regimes - emitted with sodium (HPS-control and LED lamps (100% red, 90% red + 10% blue, 70% red + 30% blue and 50% red + 50% blue light. The intensity of radiation at the height of the leaves of the plants was the same in every treatment. After harvesting, the plants were stored at the temperature of 5 °C and high humidity in plastic bags. The analyses of the material were done four times: after harvest and three times during storage at weekly intervals. Fresh weight lost, dry matter, phenolics and chlorophyll content were analysed. Additionally, the fluorescence of chlorophyll a was carried out. Changes in plant fresh weight and dry matter content during storage did not depend on the lighting used during cultivation. After 3 weeks of storage, higher value of indicator of the vitality of PSII (PIABS - Performance Index was noticed in leaves treated with higher red light intensity during cultivation (100%, 90% and 70% red. LED lamps, which emitted 100% and 90% red light, enhanced concentration of total phenolics in lamb’s lettuce leaves. Light of HPS lamps decreased radical scavenging activity in leaves. Quality and usefulness of plants produced under LED lamps was just as good as those grown under HPS lamps.

  10. EFFECT OF DIFFERENT SUBSTRATES ON THE GROWTH AND YIELD OF TOMATO (Lycopersicum esculentum Mill UNDER GREENHOUSE CONDITIONS

    Directory of Open Access Journals (Sweden)

    Luis Daniel Ortega-Martínez

    2010-09-01

    Full Text Available The tomato (Lycopersicum esculentum Mill is the world's second most important vegetable. In Mexico, the crop gains economic and social relevance by the generation of foreign exchange and jobs, the production systems of this vegetable have been diversified in order to increase performance, incorporating innovative technologies such as plastic covers, drop irrigation and hydroponics. One of the main factors determining the success of the crop is the substrate, being the medium in which roots were developed which have great influence on the growth and development. In thisstudy, we evaluated during the crop season 2008-2009, the effect of substrate: pine sawdust, compost of sheep manure, agricultural land and red volcanic rock, on growth and yield of tomato. The experimental design used was randomized complete block with four repetitions and ten treatments were evaluated results from a combination of substrates in a volume of 1:1, each experimental unit consisted of four plants, the studied variables were subjected to an analysis of variance (ANOVA using the statistical package Statistical Package for the Social Sciences (SPSS. The genotype used was Sun 7705. Significant differences between substrates, composting with sawdust mixing affected to a greater response for the variables height 4.61 m, 2.1 cm thick of stem, the fruits of greater weight 107.8 g, yield per plant and 4 kg and 25 kg/m-2. However, the number of flowers and clusters was higher in the sawdust substrate, so the composting with sawdust mixture may be a viable option for greenhouse tomato production.

  11. 77 FR 54930 - Carlyle Plastics and Resins, Formerly Known as Fortis Plastics, A Subsidiary of Plastics...

    Science.gov (United States)

    2012-09-06

    ... Employment and Training Administration Carlyle Plastics and Resins, Formerly Known as Fortis Plastics, A... plastic parts. New information shows that Fortis Plastics is now called Carlyle Plastics and Resins. In... of Carlyle Plastics and Resins, formerly known as Fortis Plastics, a subsidiary of...

  12. Effects of elevated CO2 and vascular plants on evapotranspiration in bog vegetation

    NARCIS (Netherlands)

    Heijmans, M.M.P.D.; Arp, W.J.; Berendse, F.

    2001-01-01

    We determined evapotranspiration in three experiments designed to study the effects of elevated CO2 and increased N deposition on ombrotrophic bog vegetation. Two experiments used peat monoliths with intact bog vegetation in containers, with one experiment outdoors and the other in a greenhouse. A t

  13. Our plastic age

    National Research Council Canada - National Science Library

    Richard C. Thompson; Shanna H. Swan; Charles J. Moore; Frederick S. vom Saal

    2009-01-01

    Within the last few decades, plastics have revolutionized our daily lives. Globally we use in excess of 260 million tonnes of plastic per annum, accounting for approximately 8 per cent of world oil production...

  14. Weinig plastic in vissenmaag

    NARCIS (Netherlands)

    Foekema, E.M.

    2012-01-01

    Waar de magen van sommige zeevogels vol plastic zitten, lijken vissen in de Noordzee nauwelijks last te hebben van kunststofafval. Onderzoekers die plastic resten zochten in vissenmagen vonden ze in elk geval nauwelijks.

  15. Ear Plastic Surgery

    Science.gov (United States)

    ... ENTCareers Marketplace Find an ENT Doctor Near You Ear Plastic Surgery Ear Plastic Surgery Patient Health Information ... they may improve appearance and self-confidence. Can Ear Deformities Be Corrected? Formation of the ear during ...

  16. Potent new greenhouse gas discovered

    Energy Technology Data Exchange (ETDEWEB)

    Anon

    2001-02-01

    Discovery of a new greenhouse gas by scientists of the Max Planck Institute for Chemistry in Mainz, Germany, is reported. The newly detected compound --trifluoromethyl sulfur pentafluoride -- is of industrial origin and is considered to be the most potent greenhouse gas identified to date. Its source remains a mystery, but is believed to be related to SF{sub 6}, a compound used in in high voltage electrical equipment to suppress sparks, in protecting metals during a melting process, in tennis balls, car tires and running shoes. In the past it has also been used as a noise barrier in double glazed window panes. The molecule is extremely resistant to the natural self-cleaning property of the atmosphere, has a long lifetime -- somewhere between several hundred and several thousand years. The gas was discovered during expeditions to Antarctica while extracting air samples from a thick firm layer of snow.

  17. Manipulating Sensory and Phytochemical Profiles of Greenhouse Tomatoes Using Environmentally Relevant Doses of Ultraviolet Radiation.

    Science.gov (United States)

    Dzakovich, Michael P; Ferruzzi, Mario G; Mitchell, Cary A

    2016-09-14

    Fruits harvested from off-season, greenhouse-grown tomato plants have a poor reputation compared to their in-season, garden-grown counterparts. Presently, there is a gap in knowledge with regard to the role of UV-B radiation (280-315 nm) in determining greenhouse tomato quality. Knowing that UV-B is a powerful elicitor of secondary metabolism and not transmitted through greenhouse glass and some greenhouse plastics, we tested the hypothesis that supplemental UV-B radiation in the greenhouse will impart quality attributes typically associated with garden-grown tomatoes. Environmentally relevant doses of supplemental UV-B radiation did not strongly affect antioxidant compounds of fruits, although the flavonol quercetin-3-O-rutinoside (rutin) significantly increased in response to UV-B. Physicochemical metrics of fruit quality attributes and consumer sensory panels were used to determine if any such differences altered consumer perception of tomato quality. Supplemental UV-A radiation (315-400 nm) pre-harvest treatments enhanced sensory perception of aroma, acidity, and overall approval, suggesting a compelling opportunity to environmentally enhance the flavor of greenhouse-grown tomatoes. The expression of the genes COP1 and HY5 were indicative of adaptation to UV radiation, which explains the lack of marked effects reported in these studies. To our knowledge, these studies represent the first reported use of environmentally relevant doses of UV radiation throughout the reproductive portion of the tomato plant life cycle to positively enhance the sensory and chemical properties of fruits.

  18. Greenhouse-gas payback times for crop-based biofuels

    Science.gov (United States)

    Elshout, P. M. F.; van Zelm, R.; Balkovic, J.; Obersteiner, M.; Schmid, E.; Skalsky, R.; van der Velde, M.; Huijbregts, M. A. J.

    2015-06-01

    A global increase in the demand for crop-based biofuels may be met by cropland expansion, and could require the sacrifice of natural vegetation. Such land transformation alters the carbon and nitrogen cycles of the original system, and causes significant greenhouse-gas emissions, which should be considered when assessing the global warming performance of crop-based biofuels. As an indicator of this performance we propose the use of greenhouse-gas payback time (GPBT), that is, the number of years it takes before the greenhouse-gas savings due to displacing fossil fuels with biofuels equal the initial losses of carbon and nitrogen stocks from the original ecosystem. Spatially explicit global GPBTs were derived for biofuel production systems using five different feedstocks (corn, rapeseed, soybean, sugarcane and winter wheat), cultivated under no-input and high-input farm management. Overall, GPBTs were found to range between 1 and 162 years (95% range, median: 19 years) with the longest GPBTs occurring in the tropics. Replacing no-input with high-input farming typically shortened the GPBTs by 45 to 79%. Location of crop cultivation was identified as the primary factor driving variation in GPBTs. This study underscores the importance of using spatially explicit impact assessments to guide biofuel policy.

  19. Biodegradability of Plastics

    OpenAIRE

    Yutaka Tokiwa; Calabia, Buenaventurada P.; Charles U. Ugwu; Seiichi Aiba

    2009-01-01

    Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical ...

  20. Plastic cup traps equipped with light-emitting diodes for monitoring adult Bemisia tabaci (Homoptera: Aleyrodidae).

    Science.gov (United States)

    Chu, Chang-Chi; Jackson, Charles G; Alexander, Patrick J; Karut, Kamil; Henneberry, Thomas J

    2003-06-01

    Equipping the standard plastic cup trap, also known as the CC trap, with lime-green light-emitting diodes (LED-plastic cup trap) increased its efficacy for catching Bemisia tabaci by 100%. Few Eretmocerus eremicus Rose and Zolnerowich and Encarsia formosa Gahan were caught in LED-plastic cup traps. The LED-plastic cup traps are less expensive than yellow sticky card traps for monitoring adult whiteflies in greenhouse crop production systems and are more compatible with whitefly parasitoids releases for Bemisia nymph control.

  1. Chemical Recycle of Plastics

    Directory of Open Access Journals (Sweden)

    Sara Fatima

    2014-11-01

    Full Text Available Various chemical processes currently prevalent in the chemical industry for plastics recycling have been discussed. Possible future scenarios in chemical recycling have also been discussed. Also analyzed are the effects on the environment, the risks, costs and benefits of PVC recycling. Also listed are the various types of plastics and which plastics are safe to use and which not after rcycle

  2. Plastic value chains

    DEFF Research Database (Denmark)

    Baxter, John; Wahlstrom, Margareta; Zu Castell-Rüdenhausen, Malin

    2014-01-01

    Optimizing plastic value chains is regarded as an important measure in order to increase recycling of plastics in an efficient way. This can also lead to improved awareness of the hazardous substances contained in plastic waste, and how to avoid that these substances are recycled. As an example...

  3. Propagation of Kiwi fruit with green cuttings under greenhouse conditions.

    Directory of Open Access Journals (Sweden)

    BARDHOSH FERRAJ

    2014-06-01

    Full Text Available In our country Kiwi was imported from France during the 1970s, a period that coincides with its cultivation in the Republic of Macedonia and in other regional countries especially in the ex-republics of Yugoslavia. The first saplings were placed in a national nursery in Lushnja and according to the researchers of that period this plant adapted well to the conditions, providinghigh experimental yields. In the Albanian market, the Kiwi fruit was introduced after 1991, with imported products from Greece and Italy. While in 1994 the first kiwi seedlings imported from Montenegro were planted in Balldre-Lezhe area. To scientifically conduct the production of Kiwi seedlings from vegetative rootstocks, specialists from the University of Agriculture and farmers in Lezha District conducted different rooting tests in greenhouses with controlled temperatures and an automated irrigation system.The plantings were conducted at the beginning of every month starting from May till October. The experiment was conceived in 7 variants and 3 repetitions, while planting 150 vegetative rootstock\\variant or approximately 1200 vegetative rootstocks in total. The testing variant was planted without any kind of stimulation. At the end of the experiment it resulted that the best rooting was achieved from planting the vegetative rootstocks during the months of June and July, while the worst rooting occurred from planting the rootstocks during the months of May and September. The optimal percentage of IBA Crystalline is 2500 and 3000 ppm and IBA talc is 2000 ppm.

  4. Simulation of the plant uptake of organophosphates and other emerging pollutants for greenhouse experiments and field conditions

    DEFF Research Database (Denmark)

    Trapp, Stefan; Eggen, Trine

    2013-01-01

    The uptake of the organophosphates tris(2-chloroethyl) phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCPP), tributyl phosphate (TBP), the insect repellant N,N-diethyl toluamide (DEET), and the plasticizer n-butyl benzenesulfonamide (NBBS) into plants was studied in greenhouse experiments...

  5. Biological control of Trialeurodes vaporariorum by Encarsia formosa on tomato in unheated greenhouses in the high altitude tropics

    NARCIS (Netherlands)

    Vis, de R.M.J.; Lenteren, van J.C.

    2008-01-01

    Biological control of Trialeurodes vaporariorum (Westwood) by Encarsia formosa Gahan was tested during three consecutive production cycles (16-28 weeks) on a beef tomato (Solanum lycopersicum L.) crop in a glasshouse and a plastic greenhouse on the Bogota Plateau in Colombia. During the course of th

  6. Greenhouse design for the future with a cladding material combining high insulation capacity with high light transmittance

    NARCIS (Netherlands)

    Waaijenberg, D.; Sonneveld, P.J.

    2003-01-01

    For the world exhibition Floriade 2002 in The Netherlands a greenhouse design is developed by IMAG together with General Electric Plastics, Bergen op Zoom with polycarbonate double-web sheets with a zigzag-shaped surface. Intensive research was completed to develop the special zigzag shape of the pl

  7. Attempts at propagation of the Sea Onion (Urginea maritima (L. Baker under greenhouse conditions

    Directory of Open Access Journals (Sweden)

    Eleonora Binek

    2013-12-01

    Full Text Available Propagation of Urginea maritima by seeds and bulb cuttings was carried out under greenhouse conditions. This Mediterranean species contains proscyllaridin A used for therapy. The plants after two years of propagation from 2-scale bulb cuttings had bulblet diameters (2.7 cm and mass of bulblets with roots (22.3 g about 3 and 9 times larger, respectively, in comparision with the plants reproduced from seeds. The possibility of Urginea maritima production under greenhouse conditions in our country is rather limited as this species has a slow growth and its intensive vegetation falls on the autumn-winter season.

  8. Audubon vegetation monitoring

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is the summary and the analysis of vegetative data for the Audubon Refuge from NPWRC. The data included measurements of vegetation density, vegetation...

  9. Biodegradability of plastics.

    Science.gov (United States)

    Tokiwa, Yutaka; Calabia, Buenaventurada P; Ugwu, Charles U; Aiba, Seiichi

    2009-08-26

    Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical properties (melting point, glass transition temperature, crystallinity, storage modulus etc.). In this review, microbial and enzymatic biodegradation of plastics and some factors that affect their biodegradability are discussed.

  10. Plastic value chains

    DEFF Research Database (Denmark)

    Baxter, John; Wahlstrom, Margareta; Zu Castell-Rüdenhausen, Malin

    2014-01-01

    Optimizing plastic value chains is regarded as an important measure in order to increase recycling of plastics in an efficient way. This can also lead to improved awareness of the hazardous substances contained in plastic waste, and how to avoid that these substances are recycled. As an example......, plastics from WEEE is chosen as a Nordic case study. The project aims to propose a number of improvements for this value chain together with representatives from Nordic stakeholders. Based on the experiences made, a guide for other plastic value chains shall be developed....

  11. Biodegradability of Plastics

    Directory of Open Access Journals (Sweden)

    Yutaka Tokiwa

    2009-08-01

    Full Text Available Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical properties (melting point, glass transition temperature, crystallinity, storage modulus etc.. In this review, microbial and enzymatic biodegradation of plastics and some factors that affect their biodegradability are discussed.

  12. Journal of CHINA PLASTICS

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Journal of CHINA PLASTICS was authorized and approved by The State Committee of Science and Technology of China and The Bureau of News Press of China, and published by The China Plastics Processing Industry Association,Beijing Technology and Business University and The Institute of Plastics Processing and Application of Light Industry, distributed worldwide. Since its birth in 1987, CHINA PLASTICS has become a leading magazine in plastics industry in China, a national Chinese core journal and journal of Chinese scientific and technological article statistics. It is covered by CA.

  13. Thermal Energy Storage in the Ground of a Greenhouse by the Polypropylene Capillary Heat Exchanger

    Directory of Open Access Journals (Sweden)

    M. Lazâar

    2008-01-01

    Full Text Available The problem of temperature inversion is one of solar origin principal problems about which the cultures under shelters complain. Indeed, for the winter period, the temperature under greenhouse is very low at night and it is rather high during the day in summer. Consequently, the heating of the greenhouses is essential. In this work, we studied the advisability of using two exchangers coupled between them to manage thermal energy in a greenhouse. The first system is a battery of plaits with capillary tubes buried under ground with a depth of 70 cm. The second is an air exchanger based on plastic tubes black known as agrotherms suspended with two meters and half height. The hot water, which circulates in the exchangers, is provided by the hot-water tank of the electro-solar power station of the Center of Energy Researches and Technologies (CRTEn from Tunisia.

  14. Lake Bathymetric Aquatic Vegetation

    Data.gov (United States)

    Minnesota Department of Natural Resources — Aquatic vegetation represented as polygon features, coded with vegetation type (emergent, submergent, etc.) and field survey date. Polygons were digitized from...

  15. Challenges in plastics recycling

    DEFF Research Database (Denmark)

    Pivnenko, Kostyantyn; Jakobsen, L. G.; Eriksen, Marie Kampmann

    2015-01-01

    Recycling of waste plastics still remains a challenging area in the waste management sector. The current and potential goals proposed on EU or regional levels are difficult to achieve, and even to partially fullfil them the improvements in collection and sorting should be considerable. A study...... was undertaken to investigate the factors affecting quality in plastics recycling. The preliminary results showed factors primarily influencing quality of plastics recycling to be polymer cross contamination, presence of additives, non-polymer impurities, and polymer degradation. Deprivation of plastics quality......, with respect to recycling, has been shown to happen throughout the plastics value chain, but steps where improvements may happen have been preliminary identified. Example of Cr in plastic samples analysed showed potential spreading and accumulation of chemicals ending up in the waste plastics. In order...

  16. Glassy metallic plastics

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    This paper reports a class of bulk metallic glass including Ce-, LaCe-, CaLi-, Yb-, and Sr-based metallic glasses, which are regarded as glassy metallic plastics because they combine some unique properties of both plastics and metallic alloys. These glassy metallic plastics have very low glass transition temperature (Tg~25oC to 150oC) and low Young’s modulus (~20 GPa to 35 GPa). Similar to glassy plastics, these metallic plastics show excellent plastic-like deformability on macro-, micro- and even nano-scale in their supercooled liquid range and can be processed, such as elongated, compressed, bent, and imprinted at low temperatures, in hot water for instance. Under ambient conditions, they display such metallic properties as high thermal and electric conductivities and excellent mechanical properties and other unique properties. The metallic plastics have potential applications and are also a model system for studying issues in glass physics.

  17. Variation of physical properties of LDPE greenhouse films due to agrochemicals used during cultivation

    OpenAIRE

    Evelia Schettini; Giuliano Vox

    2013-01-01

    During protected cultivation, the use of agrochemicals influence the degradation of the greenhouse plastic films. A research was carried out to evaluate how agrochemicals contamination and solar radiation influence the physical properties of low density polyethylene (LDPE) films. The LDPE films were manufactured on purpose adding different anti-UV stabilizer systems and were exposed to natural outdoor weathering at the experimental farm of the University of Bari (Italy; 41° 05’ N). Each film ...

  18. False advertising in the greenhouse?

    Science.gov (United States)

    Banse, K.

    1991-12-01

    Most scientists are convinced of the importance of their own research subjects. Broecker [1991] has deplored the temptation, if not the tendency, to go overboard and exaggerate this importance once funding enters the mind. In particular, he alleges inflated or even false claims by biological (and other) oceanographers regarding the relevance of their research to the "greenhouse effect," caused by the anthropogenic enhancement of the atmospheric CO2 content. He writes [Broecker, 1991, p. 191]: "In my estimation, on any list of subjects requiring intense study with regard to the prediction of the consequences of CO2 buildup in the atmosphere, I would place marine biological cycles near the bottom."

  19. Livestock and greenhouse gas emissions

    DEFF Research Database (Denmark)

    Herrero, M; Gerber, P; Vellinga, T

    2011-01-01

    Estimates of global greenhouse gases (GHG) emissions attributable to livestock range from 8 to 51%. This variability creates confusion among policy makers and the public as it suggests that there is a lack of consensus among scientists with regard to the contribution of livestock to global GHG...... fixed fossil C through combustion. These deviances from internationally accepted protocols create confusion and direct attention from anthropomorphic practices which have the most important contribution to global GHG emissions. Global estimates of livestock GHG emissions are most reliable when...

  20. Greater accordance with the Dietary Approaches to Stop Hypertension dietary pattern is associated with lower diet-related greenhouse gas production but higher dietary costs in the United Kingdom

    National Research Council Canada - National Science Library

    Monsivais, Pablo; Scarborough, Peter; Lloyd, Tina; Mizdrak, Anja; Luben, Robert; Mulligan, Angela A; Wareham, Nicholas J; Woodcock, James

    2015-01-01

    .... Because the DASH diet emphasizes plant-based foods, including vegetables and grains, adhering to this diet might also bring about environmental benefits, including lower associated production of greenhouse gases (GHGs...

  1. Engineering concepts for inflatable Mars surface greenhouses

    Science.gov (United States)

    Hublitz, I.; Henninger, D. L.; Drake, B. G.; Eckart, P.

    2004-01-01

    A major challenge of designing a bioregenerative life support system for Mars is the reduction of the mass, volume, power, thermal and crew-time requirements. Structural mass of the greenhouse could be saved by operating the greenhouse at low atmospheric pressure. This paper investigates the feasibility of this concept. The method of equivalent system mass is used to compare greenhouses operated at high atmospheric pressure to greenhouses operated at low pressure for three different lighting methods: natural, artificial and hybrid lighting. c2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

  2. OPIC Greenhouse Gas Emissions Analysis Details

    Data.gov (United States)

    Overseas Private Investment Corporation — Summary project inventory with independent analysis to quantify the greenhouse gas ("GHG") emissions directly attributable to projects to which the Overseas Private...

  3. Observational determination of the greenhouse effect

    Science.gov (United States)

    Raval, A.; Ramanathan, V.

    1989-01-01

    Satellite measurements are used to quantify the atmospheric greenhouse effect, defined here as the infrared radiation energy trapped by atmospheric gases and clouds. The greenhouse effect is found to increase significantly with sea surface temperature. The rate of increase gives compelling evidence for the positive feedback between surface temperature, water vapor and the greenhouse effect; the magnitude of the feedback is consistent with that predicted by climate models. This study demonstrates an effective method for directly monitoring, from space, future changes in the greenhouse effect.

  4. Greenhouse Gas Emissions From Cattle

    Directory of Open Access Journals (Sweden)

    Podkówka Zbigniew

    2015-03-01

    Full Text Available Cattle produce greenhouse gases (GHG which lead to changes in the chemical composition of the atmosphere. These gases which cause greenhouse effect include: methane (CH4, nitrous oxide (N2O, nitrogen oxides (NOx, sulphur dioxide (SO2, ammonia (NH3, dust particles and non-methane volatile organic compounds, commonly described as other than methane hydrocarbons. Fermentation processes taking place in the digestive tract produce ‘digestive gases’, distinguished from gases which are emitted during the decomposition of manure. Among these digestive gases methane and non-methane volatile organic compounds are of particular relevance importance. The amount of gases produced by cows can be reduced by choosing to rear animals with an improved genetically based performance. A dairy cow with higher production efficiency, producing milk with higher protein content and at the same time reduced fat content emits less GHG into the environment. Increasing the ratio of feed mixtures in a feed ration also reduces GHG emissions, especially of methane. By selection of dairy cows with higher production efficiency and appropriate nutrition, the farm's expected milk production target can be achieved while at the same time, the size of the herd is reduced, leading to a reduction of GHG emissions.

  5. Greenhouse gas emissions of different land uses in the delta region of Red River, Vietnam

    Science.gov (United States)

    Zhou, Minghua; Ha, Thu; An, Ngo The; Brüggemann, Nicolas

    2017-04-01

    Agricultural activities are responsible for up to a third of total anthropogenic GHG emissions. The subtropical/tropical delta areas of the large rivers in Southeast Asia are long-term history agricultural regions in the world. However, due to lack of field measurements, the estimation of the contribution of agro-ecosystems in the subtropical/tropical delta areas to global greenhouse gas emissions remains largely uncertain. Here, we conducted field experiments since January 2016 to quantify greenhouse gases (CO2, CH4 and N2O) emissions from four agricultural land uses of annual rice-rice, rice-vegetable, continuous vegetable system and fish pond in Red River delta region of Vietnam by using the transparent static chamber-gas chromatography technique. Higher N2O emissions were observed in the rice-vegetable and continuous vegetable systems, while lower N2O emissions were observed in the rice-rice and find pond systems. Compared to rice-rice system the cumulative N2O fluxes were on average twenty-fold higher in the rice-vegetable and continuous vegetable systems but significantly lower (75%) in the fish pond. Overall the net CO2 sinks were observed in the rice-rice system while other three land uses of rice-vegetable, continuous vegetable and fish pond acted as the net CO2 sources. The rice-rice and fish pond showed net CH4 emissions while variations of CH4 emissions (i.e. shifting between sources and sinks) along variations of soil moisture and temperature were observed in rice-vegetable and continuous vegetable systems. Compared to rice-rice system, the cumulative CH4 fluxes were significantly decreased by 100% for continuous vegetable system, 94% for rice-vegetable system and 89% for fish pond. Overall, the data suggest that conversion of traditional rice-rice paddy system to rice-vegetable, continuous vegetable system and find pond, which are currently undergoing driven by the economical requests and environmental changes (e.g., salinity intrusion) in this delta

  6. Bio-based and recycled polymers for cleaner production : an assessment of plastics and fibres

    OpenAIRE

    L. Shen

    2011-01-01

    Today, almost all man-made plastics and fibres are produced from synthetic polymers. Synthetic polymers, made from petroleum which took millions of years to form, have three sustainability challenges: (i) the limited fossil fuel resources, (ii) the environmental impacts caused by non-degradable plastics waste, and (iii) greenhouse gas emissions caused by combusting fossil fuels. To tackle these sustainability challenges, two strategies have been proposed. First, use bio-based polymers to repl...

  7. Bio-based and recycled polymers for cleaner production : an assessment of plastics and fibres

    OpenAIRE

    Shen, L.

    2011-01-01

    Today, almost all man-made plastics and fibres are produced from synthetic polymers. Synthetic polymers, made from petroleum which took millions of years to form, have three sustainability challenges: (i) the limited fossil fuel resources, (ii) the environmental impacts caused by non-degradable plastics waste, and (iii) greenhouse gas emissions caused by combusting fossil fuels. To tackle these sustainability challenges, two strategies have been proposed. First, use bio-based polymers to repl...

  8. Automatic handling of shade net and irrigation in greenhouse with tomatoes

    Directory of Open Access Journals (Sweden)

    Federico Hahn

    2011-03-01

    Full Text Available Greenhouse vegetable production in México and worldwide has become important. Following greenhouses automation, a simple controller was designed to open and close shading nets to reduce incident radiation and excessive evapotranspiration. Irrigation period were radiation controlled and did not turn on the pump with clouds or moon radiation, saving 35% of water. The nets remained closed during the night and were opened during scarce radiation. In the tomato greenhouse experiment, every three months analysis was carried on manual and automatic net control. Maximum incident radiation was achieved in May and August when no shading nets were used. Air temperature increased to 28°C in August decreasing by 50% fruit size. Fruit temperature decreased 2.5°C when nets were used decreasing tomato cracking.

  9. Energy Efficiency of a Greenhouse for the Conservation of Forestry Biodiversity

    Directory of Open Access Journals (Sweden)

    Alvaro Marucci

    2013-01-01

    Full Text Available Forest biodiversity conservation is one of the most interesting and crucial problems in forestry world. Currently, the conservation methods are based on two phases: the conservation of seeds at low temperatures and the multiplication of vegetable material. This latter operation can be successfully developed in properly designed greenhouses. The aim of this paper is to define a type of greenhouse which is particularly suitable for plant material propagation in order to preserve forest biodiversity in the area of the Central Italy. Some general parameters were first defined for a correct planning of the structure, such as: the shape of the section, volume, cover material, systems for heating and cooling, and those for the control of the internal microclimate parameters (light, air temperature, and relative humidity. Considering the construction characteristics and the climatic conditions of the place, the internal microclimatic conditions have been later determined by the useful implementation in TRNSYS in order to analyse the energy efficiency of the greenhouse.

  10. Plastic Pollution from Ships

    OpenAIRE

    Čulin, Jelena; Bielić, Toni

    2016-01-01

    The environmental impact of shipping on marine environment includes discharge of garbage. Plastic litter is of particular concern due to abundance, resistance to degradation and detrimental effect on marine biota. According to recently published studies, a further research is required to assess human health risk. Monitoring data indicate that despite banning plastic disposal at sea, shipping is still a source of plastic pollution. Some of the measures to combat the problem are discussed.

  11. Handbook of Plastic Welding

    DEFF Research Database (Denmark)

    Islam, Aminul

    The purpose of this document is to summarize the information about the laser welding of plastic. Laser welding is a matured process nevertheless laser welding of micro dimensional plastic parts is still a big challenge. This report collects the latest information about the laser welding of plasti...... as a knowledge handbook for laser welding of plastic components. This document should provide the information for all aspects of plastic laser welding and help the design engineers to take all critical issues into consideration from the very beginning of the design phase....

  12. Plastics and health risks.

    Science.gov (United States)

    Halden, Rolf U

    2010-01-01

    By 2010, the worldwide annual production of plastics will surpass 300 million tons. Plastics are indispensable materials in modern society, and many products manufactured from plastics are a boon to public health (e.g., disposable syringes, intravenous bags). However, plastics also pose health risks. Of principal concern are endocrine-disrupting properties, as triggered for example by bisphenol A and di-(2-ethylhexyl) phthalate (DEHP). Opinions on the safety of plastics vary widely, and despite more than five decades of research, scientific consensus on product safety is still elusive. This literature review summarizes information from more than 120 peer-reviewed publications on health effects of plastics and plasticizers in lab animals and humans. It examines problematic exposures of susceptible populations and also briefly summarizes adverse environmental impacts from plastic pollution. Ongoing efforts to steer human society toward resource conservation and sustainable consumption are discussed, including the concept of the 5 Rs--i.e., reduce, reuse, recycle, rethink, restrain--for minimizing pre- and postnatal exposures to potentially harmful components of plastics.

  13. Synaptic Plasticity and Nociception

    Institute of Scientific and Technical Information of China (English)

    ChenJianguo

    2004-01-01

    Synaptic plasticity is one of the fields that progresses rapidly and has a lot of success in neuroscience. The two major types of synaptie plasticity: long-term potentiation ( LTP and long-term depression (LTD are thought to be the cellular mochanisms of learning and memory. Recently, accumulating evidence suggests that, besides serving as a cellular model for learning and memory, the synaptic plasticity involves in other physiological or pathophysiological processes, such as the perception of pain and the regulation of cardiovascular system. This minireview will focus on the relationship between synaptic plasticity and nociception.

  14. Research of South Xinjiang Intelligent Control of Greenhouse Based on Multi-sensor Data Fusion%南疆地区智能温室控制系统研究-基于多传感器融合机理

    Institute of Scientific and Technical Information of China (English)

    王宪磊; 裴玖玲; 刘润泽; 弋晓康

    2017-01-01

    It is very necessary for the southern of Xinjiang-based of facilities , to agricultural research for intelligent greenhouse plastic greenhouses .This paper in connection with the situation of facility agriculture in the southern of Xin-jiang,combine Fuzzy inference algorithms and expert systems to establish a suitable under natural climatic conditions of southern greenhouse intelligent automatic control model .Through the acquisition and integration of real-time southern re-gions greenhouse control parameters , the system can obtain accurate monitoring results .The results show that this method improves the accuracy of decision-making parameters greenhouse environment monitoring and control , effective solution to control the accuracy of agricultural facilities ,provide further solutions to increase crop production ,it has a very impor-tant practical significance to alleviate the practical issues such as shortages of vegetables other agricultural .%针对南疆以塑料大棚为主的设施农业,智能温室的研究显得十分必要。为此,针对南疆设施农业的现状,基于多传感器数据融合技术,将模糊推理算法与专家系统结合起来,建立了适用于南疆自然气候条件下的智能温室自动化控制模型。通过采集和融合南疆地区实时温室控制参数,该系统可以取得精确的监控结果。结果表明:该方法提高了温室环境参数测控的决策准确性,有效解决了设施农业的控制精度,为增大农作物产能提供进一步解决措施,对缓解南疆蔬菜等农产品紧缺等实际问题具有十分重要的实际意义。

  15. Compost amendment of sandy soil affects soil properties and greenhouse tomato productivity

    DEFF Research Database (Denmark)

    Arthur, Emmanuel; Cornelis, W.; Razzaghi, Fatemeh

    2012-01-01

    Sandy soils, with low productivity, could be improved by compost application to sustain crop production. This study aimed to examine the effect of three compost types (vegetable, fruit and yard waste compost, garden waste compost, and spent mushroom compost) on basic properties of a loamy sand...... and greenhouse tomato productivity. Disturbed and intact soil samples were taken from a decade-long compost field experiment on loamy sand with three compost types at application rate of 30 m3 ha-1 yr-1 (7.5 ton ha-1 yr-1). The soils were characterized for chemical and physical properties. Tomato was planted...... in a greenhouse using soil samples from the field and vegetative and yield parameters (plant height, stem diameter, leaf number, and fruit yield), water productivity, and harvest index were evaluated. All compost types significantly increased soil total carbon, total nitrogen, pH, electrical conductivity...

  16. The effects of light-emitting diode lighting on greenhouse plant growth and quality

    Directory of Open Access Journals (Sweden)

    Margit Olle

    2013-06-01

    Full Text Available The aim of this study is to present the light emitting diode (LED technology for greenhouse plant lighting and to give an overview about LED light effects on photosynthetic indices, growth, yield and nutritional value in green vegetables and tomato, cucumber, sweet pepper transplants. The sole LED lighting, applied in closed growth chambers, as well as combinations of LED wavelengths with conventional light sources, fluorescent and high pressure sodium lamp light, and natural illumination in greenhouses are overviewed. Red and blue light are basal in the lighting spectra for green vegetables and tomato, cucumber, and pepper transplants; far red light, important for photomorphogenetic processes in plants also results in growth promotion. However, theoretically unprofitable spectral parts as green or yellow also have significant physiological effects on investigated plants. Presented results disclose the variability of light spectral effects on different plant species and different physiological indices.

  17. Monitoring vegetation water uptake in a semiarid riparian corridor

    Science.gov (United States)

    Robinson, J.; Ochoa, C. G.; Leonard, J.

    2015-12-01

    With a changing global climate and growing demand for water throughout the world, responsible and sustainable land and water resource management practices are becoming increasingly important. Accounting for the amount of water used by riparian vegetation is a critical element for better managing water resources in arid and semiarid environments. The objective of this study was to determine water uptake by selected riparian vegetative species in a semiarid riparian corridor in North-Central Oregon. Exo-skin sap flow sensors (Dynamax, Houston, TX, U.S.A.) were used to measure sap flux in red alder (Alnus rubra) trees, the dominant overstory vegetation at the field site. Xylem sap flow data was collected from selected trees at the field site and in a greenhouse setting. Transpiration rates were determined based on an energy balance method, which makes it possible to estimate the mass flow of sap by measuring the velocity of electrical heat pulses through the plant stem. Preliminary field results indicate that red alder tree branches of about 1 inch diameter transpire between 2 and 6 kg of water/day. Higher transpiration rates of up to 7.3 kg of water/day were observed under greenhouse conditions. Streamflow and stream water temperature, vegetation characteristics, and meteorological data were analyzed in conjunction with transpiration data. Results of this study provide insight on riparian vegetation water consumption in water scarce ecosystems. This study is part of an overarching project focused on climate-vegetation interactions and ecohydrologic processes in arid and semiarid landscapes.

  18. Native Grasses as a Management Alternative on Vegetated Closure Caps

    Science.gov (United States)

    Kwit, Charles; Collins, Beverly

    2008-06-01

    Capped waste sites often are vegetated with commercial turf grasses to increase evapotranspiration and prevent erosion and possible exposure of the barrier. Fertilizer, frequent watering, and mowing may be required to establish the turf grass and prevent invasion by trees and shrubs. Oldfield vegetation of grasses and forbs is a possible sustainable alternative to turf grass communities. To determine if oldfield vegetation can establish on caps, we (1) compared establishment of a dominant oldfield grass and a commercial turf grass under different combinations of new closure cap management: spring or summer planting and presence or absence of amendments to alleviate drought (watering, mulch) or increase soil fertility (fertilizer, lime, a nitrogen-fixing legume); (2) surveyed existing caps to determine if oldfield species establish naturally; and (3) performed a greenhouse experiment to compare growth of two native grasses under low and amended (added water, soil nutrients) conditions. Both the commercial grass and oldfield species established under new cap conditions; fertilizer, water, and mulch improved vegetation establishment in spring or summer, but legumes decreased grass cover. In the greenhouse, both native grasses grew best with amendments; however, substantial stem and root length were obtained with no fertilizer and only once-weekly watering. Existing vegetated caps supported planted grasses and naturally established oldfield species. Overall, the results indicate native grasses can establish on new caps and oldfields can serve as a management model; further work is needed to determine the management strategy to maintain herbaceous vegetation and slow woody species invasion.

  19. Biodiversity of Terrestrial Vegetation during Past Warm Periods

    Science.gov (United States)

    Davies-Barnard, T.; Valdes, P. J.; Ridgwell, A.

    2016-12-01

    Previous modelling studies of vegetation have generally used a small number of plant functional types to understand how the terrestrial biosphere responds to climate changes. Whilst being useful for understanding first order climate feedbacks, this climate-envelope approach makes a lot of assumptions about past vegetation being very similar to modern. A trait-based method has the advantage for paleo modelling in that there are substantially less assumptions made. In a novel use of the trait-based dynamic vegetation model JeDi, forced with output from climate model HadCM3, we explore past biodiversity and vegetation carbon changes. We use JeDi to model an optimal 2000 combinations of fifteen different traits to enable assessment of the overall level of biodiversity as well as individual growth strategies. We assess the vegetation shifts and biodiversity changes in past greenhouse periods to better understand the impact on the terrestrial biosphere. This work provides original insights into the response of vegetation and terrestrial carbon to climate and hydrological changes in high carbon dioxide climates over time, including during the Late Permian and Cretaceous. We evaluate how the location of biodiversity hotspots and species richness in past greenhouse climates is different to the present day.

  20. Quantification and Controls of Wetland Greenhouse Gas Emissions

    Energy Technology Data Exchange (ETDEWEB)

    McNicol, Gavin [Univ. of California, Berkeley, CA (United States)

    2016-05-10

    Wetlands cover only a small fraction of the Earth’s land surface, but have a disproportionately large influence on global climate. Low oxygen conditions in wetland soils slows down decomposition, leading to net carbon dioxide sequestration over long timescales, while also favoring the production of redox sensitive gases such as nitrous oxide and methane. Freshwater marshes in particular sustain large exchanges of greenhouse gases under temperate or tropical climates and favorable nutrient regimes, yet have rarely been studied, leading to poor constraints on the magnitude of marsh gas sources, and the biogeochemical drivers of flux variability. The Sacramento-San Joaquin Delta in California was once a great expanse of tidal and freshwater marshes but underwent drainage for agriculture during the last two centuries. The resulting landscape is unsustainable with extreme rates of land subsidence and oxidation of peat soils lowering the surface elevation of much of the Delta below sea level. Wetland restoration has been proposed as a means to slow further subsidence and rebuild peat however the balance of greenhouse gas exchange in these novel ecosystems is still poorly described. In this dissertation I first explore oxygen availability as a control on the composition and magnitude of greenhouse gas emissions from drained wetland soils. In two separate experiments I quantify both the temporal dynamics of greenhouse gas emission and the kinetic sensitivity of gas production to a wide range of oxygen concentrations. This work demonstrated the very high sensitivity of carbon dioxide, methane, and nitrous oxide production to oxygen availability, in carbon rich wetland soils. I also found the temporal dynamics of gas production to follow a sequence predicted by thermodynamics and observed spatially in other soil or sediment systems. In the latter part of my dissertation I conduct two field studies to quantify greenhouse gas exchange and understand the carbon sources for

  1. Seasonal variation of heat consumption in greenhouses

    DEFF Research Database (Denmark)

    Nielsen, O.F.; Amsen, M.G.; Strøm, J.S.

    The concept of dynamic variation is introduced as a method to visualize the dynamic fluctuations of heat consumption and thermal climate in greenhouses. The feasibility of the concept is illustrated by describing effects of different greenhouse designs. Engineering data on design heat consumption...

  2. Climate and Yield in a closed greenhouse

    NARCIS (Netherlands)

    Heuvelink, E.; Bakker, M.J.; Marcelis, L.F.M.; Raaphorst, M.

    2008-01-01

    The so-called closed greenhouse (closed ventilation windows) is a recent innovation in Dutch greenhouse industry. The technical concept consists of a heat pump, underground (aquifer) seasonal energy storage as well as daytime storage, air treatment units with heat exchangers, and air distribution du

  3. Greenhouse climate management : an optimal control approach

    NARCIS (Netherlands)

    Henten, van E.J.

    1994-01-01

    In this thesis a methodology is developed for the construction and analysis of an optimal greenhouse climate control system.

    In chapter 1, the results of a literature survey are presented and the research objectives are defined. In the literature, optimal greenhouse climate

  4. Greenhouse climate control affects postharvest tomato quality

    NARCIS (Netherlands)

    Farneti, B.; Schouten, R.E.; Qian, T.; Dieleman, J.A.; Tijskens, L.M.M.; Woltering, E.J.

    2013-01-01

    In this study, important quality properties such as firmness, sugar and acid levels were measured and analysed in tomatoes harvested from three greenhouses during a five month period and stored at 16 degrees C for over 20 days. Tomatoes were harvested from three identical, neighbouring, greenhouses

  5. Climatic evaluation of semi-closed greenhouses

    NARCIS (Netherlands)

    Campen, J.B.; Kempkes, F.L.K.

    2011-01-01

    In the Netherlands the development of semi-closed greenhouses is going on for eight years. Increased carbon dioxide levels, reduced pesticide use, and energy saving are the main benefits of semi-closed greenhouses. Companies have developed several concepts with the goal to reduce the ventilation wit

  6. The greenhouse gas balance of the landscape

    NARCIS (Netherlands)

    Nol, Linda; Neubert, Rolf; Vermeulen, Alex; Vellinga, Olaf; Meesters, Antoon; Tolk, Lieselotte; Olivier, Jos; Peters, Wouter; Lesschen, Jan Peter; Hutjes, Ronald; Moors, Eddy

    2010-01-01

    It is difficult to measure or even estimate the Dutch greenhouse gas emissions of the landscape, because we cannot put a flux chamber over the entire Netherlands. Greenhouse gas emissions are usually estimated by bottom-up methods or top-down methods. The Netherlands report most emissions to the

  7. A Hiatus of the Greenhouse Effect.

    Science.gov (United States)

    Song, Jinjie; Wang, Yuan; Tang, Jianping

    2016-09-12

    The rate at which the global average surface temperature is increasing has slowed down since the end of the last century. This study investigates whether this warming hiatus results from a change in the well-known greenhouse effect. Using long-term, reliable, and consistent observational data from the Earth's surface and the top of the atmosphere (TOA), two monthly gridded atmospheric and surface greenhouse effect parameters (Ga and Gs) are estimated to represent the radiative warming effects of the atmosphere and the surface in the infrared range from 1979 to 2014. The atmospheric and surface greenhouse effect over the tropical monsoon-prone regions is found to contribute substantially to the global total. Furthermore, the downward tendency of cloud activity leads to a greenhouse effect hiatus after the early 1990 s, prior to the warming pause. Additionally, this pause in the greenhouse effect is mostly caused by the high number of La Niña events between 1991 and 2014. A strong La Niña indicates suppressed convection in the tropical central Pacific that reduces atmospheric water vapor content and cloud volume. This significantly weakened regional greenhouse effect offsets the enhanced warming influence in other places and decelerates the rising global greenhouse effect. This work suggests that the greenhouse effect hiatus can be served as an additional factor to cause the recent global warming slowdown.

  8. Greenhouse gas emissions from South Africa

    CSIR Research Space (South Africa)

    Scholes, RJ

    1996-05-01

    Full Text Available South African greenhouse gas emissions contributed about 1.2% to the global increase in the greenhouse effect in 1988. South Africa generated trace gases with a radiation absorption potential over a 20-year period equivalent to 534 million tons...

  9. Greenhouse climate management: an optimal control approach.

    NARCIS (Netherlands)

    Henten, van E.J.

    1994-01-01

    In this thesis a methodology is developed for the construction and analysis of an optimal greenhouse climate control system.In chapter 1, the results of a literature survey are presented and the research objectives are defined. In the literature, optimal greenhouse climate management systems have be

  10. A Hiatus of the Greenhouse Effect

    Science.gov (United States)

    Song, Jinjie; Wang, Yuan; Tang, Jianping

    2016-09-01

    The rate at which the global average surface temperature is increasing has slowed down since the end of the last century. This study investigates whether this warming hiatus results from a change in the well-known greenhouse effect. Using long-term, reliable, and consistent observational data from the Earth’s surface and the top of the atmosphere (TOA), two monthly gridded atmospheric and surface greenhouse effect parameters (Ga and Gs) are estimated to represent the radiative warming effects of the atmosphere and the surface in the infrared range from 1979 to 2014. The atmospheric and surface greenhouse effect over the tropical monsoon-prone regions is found to contribute substantially to the global total. Furthermore, the downward tendency of cloud activity leads to a greenhouse effect hiatus after the early 1990 s, prior to the warming pause. Additionally, this pause in the greenhouse effect is mostly caused by the high number of La Niña events between 1991 and 2014. A strong La Niña indicates suppressed convection in the tropical central Pacific that reduces atmospheric water vapor content and cloud volume. This significantly weakened regional greenhouse effect offsets the enhanced warming influence in other places and decelerates the rising global greenhouse effect. This work suggests that the greenhouse effect hiatus can be served as an additional factor to cause the recent global warming slowdown.

  11. Titan's greenhouse and antigreenhouse effects

    Science.gov (United States)

    Mckay, Christopher P.; Pollack, James B.; Courtin, Regis

    1992-01-01

    Thermal mechanisms active in Titan's atmosphere are discussed in a brief review of data obtained during the Voyager I flyby in 1980. Particular attention is given to the greenhouse effect (GHE) produced by atmospheric H2, N2, and CH4; this GHE is stronger than that on earth, with CH4 and H2 playing roles similar to those of H2O and CO2 on earth. Also active on Titan is an antigreenhouse effect, in which dark-brown and orange organic aerosols block incoming solar light while allowing IR radiation from the Titan surface to escape. The combination of GHE and anti-GHE leads to a surface temperature about 12 C higher than it would be if Titan had no atmosphere.

  12. Experiment of Green Disease Control on Greenhouse Tomatoes%大棚番茄绿色控病试验

    Institute of Scientific and Technical Information of China (English)

    莫怡琴; 刘泉

    2015-01-01

    为探索防治番茄晚疫病、灰霉病等的绿色控病技术,采用大棚滴灌控病、大棚膜下滴灌控病、大棚膜下滴灌配套uvc(杀菌消毒灯)控病进行试验,结果3种技术都能减轻番茄晚疫病和灰霉病的发生,但以大棚膜下滴灌配套uvc技术对番茄2种主要病害的控病效果最好,可在生产中推广使用。%To explore green disease control technologies of the prevention of tomato late blight and gray mold, we carried out a experiment with three disease-control technologies including greenhouse drip irrigation, greenhouse drip irrigation under plastic film and greenhouse drip irrigation under plastic film combined with uvc respectively. The results showed that, all the three technologies were able to reduce the occurrence rate of tomato late blight and gray mold, but greenhouse drip irrigation under plastic film combined with uvc was more effective in controlling various diseases of tomatoes.

  13. Energy Flexibility of The Commercial Greenhouse Growers

    DEFF Research Database (Denmark)

    Ma, Zheng; Jørgensen, Bo Nørregaard

    2016-01-01

    The commercial greenhouses can provide energy flexibility with the artificial lighting usage. Therefore, the commercial greenhouse growers can potentially play an important role in the electricity market as providers of flexibility services with the technology and software readiness. This paper...... takes Danish commercial growers and the Nordic regulating market as an example, to investigate the market potential with two business models. One business model is that commercial greenhouse growers directly participate in the regulating market. Another model is rescuing the BRPs’ (Balance Responsible...... Parties) imbalance error. Two calculations are formulated to evaluate the monetary benefits for the commercial greenhouse growers’ participation in both business models. The positive results indicate potential and benefits for the Danish commercial greenhouse growers’ participation in the electricity...

  14. GREENHOUSE GASES AND MEANS OF PREVENTION

    Directory of Open Access Journals (Sweden)

    Dušica Stojanović

    2013-09-01

    Full Text Available The greenhouse effect can be defined as the consequence of increased heating of the Earth's surface, as well as the lower atmosphere by carbon dioxide, water vapor, and other trace amounts gases. It is well-known that human industrial activities have released large amounts of greenhouse gases in the atmosphere, about 900 billion tons of carbon dioxide, and it is estimated that up to 450 billion are still in the atmosphere. In comparison to greenhouse gases water vapor is one of the greatest contributors to the greenhouse effect on Earth. Many projects, as does the PURGE project, have tendences to build on the already conducted research and to quantify the positive and negative impacts on health and wellbeing of the population with greenhouse gas reduction strategies that are curently being implemented and should be increasingly applied in various sectors and urban areas, having offices in Europe, China and India.

  15. Energy Flexibility of The Commercial Greenhouse Growers

    DEFF Research Database (Denmark)

    Ma, Zheng; Jørgensen, Bo Nørregaard

    2017-01-01

    The commercial greenhouses can provide energy flexibility with the artificial lighting usage. Therefore, the commercial greenhouse growers can potentially play an important role in the electricity market as providers of flexibility services with the technology and software readiness. This paper...... Parties) imbalance error. Two calculations are formulated to evaluate the monetary benefits for the commercial greenhouse growers’ participation in both business models. The positive results indicate potential and benefits for the Danish commercial greenhouse growers’ participation in the electricity...... takes Danish commercial growers and the Nordic regulating market as an example, to investigate the market potential with two business models. One business model is that commercial greenhouse growers directly participate in the regulating market. Another model is rescuing the BRPs’ (Balance Responsible...

  16. Halos of Plastic

    Institute of Scientific and Technical Information of China (English)

    Maya Reid

    2012-01-01

    The halos that span South Africa's coastline are anything but angelic. Fanning out around four major urban centers-Cape Town, Port Elizabeth, East London and Durban-they are made up of innumerable bits and pieces of plastic. As a form of pollution, their shelflife is unfathomable. Plastic is essentially chemically inactive. It's designed to never break down.

  17. Biodegradation of plastics.

    Science.gov (United States)

    Shimao, M

    2001-06-01

    Widespread studies on the biodegradation of plastics have been carried out in order to overcome the environmental problems associated with synthetic plastic waste. Recent work has included studies of the distribution of synthetic polymer-degrading microorganisms in the environment, the isolation of new microorganisms for biodegradation, the discovery of new degradation enzymes, and the cloning of genes for synthetic polymer-degrading enzymes.

  18. DESIGNERS’ KNOWLEDGE IN PLASTICS

    DEFF Research Database (Denmark)

    Eriksen, Kaare

    2013-01-01

    The Industrial designers’ knowledge in plastics materials and manufacturing principles of polymer products is very important for the innovative strength of the industry, according to a group of Danish plastics manufacturers, design students and practicing industrial designers. These three groups...... answered the first Danish national survey, PD13[1], investigating the importance of industrial designers’ knowledge in plastics and the collaboration between designers and the polymer industry. The plastics industry and the industrial designers collaborate well, but both groups frequently experience...... that the designers’ lack of knowledge concerning polymer materials and manufacturing methods can be problematic or annoying, and design students from most Danish design universities express the need for more contact with the industry and more competencies and tools to handle even simple topics when designing plastic...

  19. Consciousness and neural plasticity

    DEFF Research Database (Denmark)

    In contemporary consciousness studies the phenomenon of neural plasticity has received little attention despite the fact that neural plasticity is of still increased interest in neuroscience. We will, however, argue that neural plasticity could be of great importance to consciousness studies....... If consciousness is related to neural processes it seems, at least prima facie, that the ability of the neural structures to change should be reflected in a theory of this relationship "Neural plasticity" refers to the fact that the brain can change due to its own activity. The brain is not static but rather...... the relation between consciousness and brain functions. If consciousness is connected to specific brain structures (as a function or in identity) what happens to consciousness when those specific underlying structures change? It is therefore possible that the understanding and theories of neural plasticity can...

  20. Thermodynamics of greenhouse systems for the northern latitudes: analysis, evaluation and prospects for primary energy saving.

    Science.gov (United States)

    Bronchart, Filip; De Paepe, Michel; Dewulf, Jo; Schrevens, Eddie; Demeyer, Peter

    2013-04-15

    In Flanders and the Netherlands greenhouse production systems produce economically important quantities of vegetables, fruit and ornamentals. Indoor environmental control has resulted in high primary energy use. Until now, the research on saving primary energy in greenhouse systems has been mainly based on analysis of energy balances. However, according to the thermodynamic theory, an analysis based on the concept of exergy (free energy) and energy can result in new insights and primary energy savings. Therefore in this paper, we analyse the exergy and energy of various processes, inputs and outputs of a general greenhouse system. Also a total system analysis is then performed by linking the exergy analysis with a dynamic greenhouse climate growth simulation model. The exergy analysis indicates that some processes ("Sources") lie at the origin of several other processes, both destroying the exergy of primary energy inputs. The exergy destruction of these Sources is caused primarily by heat and vapour loss. Their impact can be compensated by exergy input from heating, solar radiation, or both. If the exergy destruction of these Sources is reduced, the necessary compensation can also be reduced. This can be accomplished through insulating the greenhouse and making the building more airtight. Other necessary Sources, namely transpiration and loss of CO2, have a low exergy destruction compared to the other Sources. They are therefore the best candidate for "pump" technologies ("vapour heat pump" and "CO2 pump") designed to have a low primary energy use. The combination of these proposed technologies results in an exergy efficient greenhouse with the highest primary energy savings. It can be concluded that exergy analyses add additional information compared to only energy analyses and it supports the development of primary energy efficient greenhouse systems.

  1. PLASTIC MATERIALS IN EUROPEAN AGRICULTURE: ACTUAL USE AND PERSPECTIVES

    Directory of Open Access Journals (Sweden)

    Giacomo Scarascia-Mugnozza

    2012-06-01

    Full Text Available The world consumption of plastics in agriculture amounts yearly to 6.5 million tons. In addition to conventional polymers used in agriculture for greenhouses and mulches such as PE, PVC, EVA, photo-selective and luminescent polymers have been used, in order to improve the quality of crops. For the same reason plastic nets are used mainly in countries with tropical and Mediterranean climates. For an environmentally friendly agricultural activity, an alternative strategy can be represented by bio-based agricultural raw materials. For low environmental impact applications, biodegradable materials for agricultural films are nowadays produced. An overview of the main methods for the disposal and recycling of plastic materials are presented with the results of mechanical and radiometric tests on recycled plastics. The strategies to reduce the burden of plastics in agriculture are: a correct procedure for the collection, disposal and recycling of post-consumption plastics; the increase of lifetime duration and performance; and the introduction and promotion of bio-based materials.

  2. Advancing agricultural greenhouse gas quantification*

    Science.gov (United States)

    Olander, Lydia; Wollenberg, Eva; Tubiello, Francesco; Herold, Martin

    2013-03-01

    1. Introduction Better information on greenhouse gas (GHG) emissions and mitigation potential in the agricultural sector is necessary to manage these emissions and identify responses that are consistent with the food security and economic development priorities of countries. Critical activity data (what crops or livestock are managed in what way) are poor or lacking for many agricultural systems, especially in developing countries. In addition, the currently available methods for quantifying emissions and mitigation are often too expensive or complex or not sufficiently user friendly for widespread use. The purpose of this focus issue is to capture the state of the art in quantifying greenhouse gases from agricultural systems, with the goal of better understanding our current capabilities and near-term potential for improvement, with particular attention to quantification issues relevant to smallholders in developing countries. This work is timely in light of international discussions and negotiations around how agriculture should be included in efforts to reduce and adapt to climate change impacts, and considering that significant climate financing to developing countries in post-2012 agreements may be linked to their increased ability to identify and report GHG emissions (Murphy et al 2010, CCAFS 2011, FAO 2011). 2. Agriculture and climate change mitigation The main agricultural GHGs—methane and nitrous oxide—account for 10%-12% of anthropogenic emissions globally (Smith et al 2008), or around 50% and 60% of total anthropogenic methane and nitrous oxide emissions, respectively, in 2005. Net carbon dioxide fluxes between agricultural land and the atmosphere linked to food production are relatively small, although significant carbon emissions are associated with degradation of organic soils for plantations in tropical regions (Smith et al 2007, FAO 2012). Population growth and shifts in dietary patterns toward more meat and dairy consumption will lead to

  3. The Weird Vegetable Price

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The Chinese Government faces the task of stabilizing vegetable prices to avoid steep increases and dips Fluctuations of vegetable prices in China have recently caused near panic in the domestic market.Purchase prices for farm produce are decreasing dramatically

  4. Procedures for Sampling Vegetation

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report outlines vegetation sampling procedures used on various refuges in Region 3. The importance of sampling the response of marsh vegetation to management...

  5. Total Vegetation 2002

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These are polygons that contain vegetated pixels in the May, 2002 imagery from aerial overflight of the Grand Canyon. Vegetation was mapped between stage elevations...

  6. Greenhouse gas mitigation options for Washington State

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, N.

    1996-04-01

    President Clinton, in 1993, established a goal for the United States to return emissions of greenhouse gases to 1990 levels by the year 2000. One effort established to help meet this goal was a three part Environmental Protection Agency state grant program. Washington State completed part one of this program with the release of the 1990 greenhouse gas emissions inventory and 2010 projected inventory. This document completes part two by detailing alternative greenhouse gas mitigation options. In part three of the program EPA, working in partnership with the States, may help fund innovative greenhouse gas reduction strategies. The greenhouse gas control options analyzed in this report have a wide range of greenhouse gas reductions, costs, and implementation requirements. In order to select and implement a prudent mix of control strategies, policy makers need to have some notion of the potential change in climate, the consequences of that change and the uncertainties contained therein. By understanding the risks of climate change, policy makers can better balance the use of scarce public resources for concerns that are immediate and present against those that affect future generations. Therefore, prior to analyzing alternative greenhouse gas control measures, this report briefly describes the phenomenon and uncertainties of global climate change, and then projects the likely consequences for Washington state.

  7. Economic growth and greenhouse gas emissions

    Energy Technology Data Exchange (ETDEWEB)

    Ansuategi, Alberto [Environment Department, University of York, York (United Kingdom); Escapa, Marta [Foundations of Economic Analysis Department, University of the Basque Country, Bilbao (Spain)

    2002-01-01

    Recent empirical research has examined the relationship between certain indicators of environmental degradation and income, concluding that in some cases an inverted U-shaped relationship, which has been called an environmental Kuznets curve (EKC), exists between these variables. Unfortunately, this inverted U-shaped relationship does not hold for greenhouse gas emissions. One explanation of the absence of EKC-like behavior in greenhouse gas emissions is that greenhouse gases are special pollutants that create global, not local, disutility. But the international nature of global warming is not the only reason that prevents de-linking greenhouse gas emissions from economic growth. The intergenerational nature of the negative impact of greenhouse gas emissions may have also been an important factor preventing the implementation of greenhouse gas abatement measures in the past. In this paper we explore the effect that the presence of intergenerational spillovers has on the emissions-income relationship. We use a numerically calibrated overlapping generations model of climate-economy interactions. We conclude that: (1) the intertemporal responsibility of the regulatory agency, (2) the institutional capacity to make intergenerational transfers and (3) the presence of intergenerationally lagged impact of emissions constitute important determinants of the relationship between economic growth and greenhouse gas emissions.

  8. The solar energy-saving plastic film greenhouses constructed in Zhangye City and a preliminary discussion on the resistance of vegetables to low temperature and chilling injury climate%张掖市日光温室及蔬菜抵抗低温冷害冻害天气能力探讨

    Institute of Scientific and Technical Information of China (English)

    张文斌; 张东昱; 陈修斌

    2009-01-01

    低温障碍是造成河西走廊温室蔬菜减产的一大生理病害.为了掌握不同类型日光温室及蔬菜抵抗低温冷害和冻害天气的能力,自2008年1月中旬起,笔者在甘州、临泽、高台3县(区)设立6个不同类型的点开展了相关方面的观察和记载,分析了造成低温障碍的原因.提出了科学建造温室、配套水电设施、增施有机肥、增加覆盖物、架设碘钨灯、嫁接育苗、低温锻炼、喷施防冻剂等预防措施,并立项开展温室蔬菜低温障碍研究,特别是冰核细菌与蔬菜冻害关系的研究,最终实现控制或减轻蔬菜冻害是蔬菜冻害研究的一个新的领域.

  9. Dutch Vegetation Database (LVD)

    NARCIS (Netherlands)

    Hennekens, S.M.

    2011-01-01

    The Dutch Vegetation Database (LVD) hosts information on all plant communities in the Netherlands. This substantial archive consists of over 600.000 recent and historic vegetation descriptions. The data provide information on more than 85 years of vegetation recording in various habitats covering te

  10. The greenhouse and antigreenhouse effects on Titan

    Science.gov (United States)

    Mckay, Christopher P.; Pollack, James B.; Courtin, Regis

    1991-01-01

    The parallels between the atmospheric thermal structure of the Saturnian satellite Titan and the hypothesized terrestrial greenhouse effect can serve as bases for the evaluation of competing greenhouse theories. Attention is presently drawn to the similarity between the roles of H2 and CH4 on Titan and CO2 and H2O on earth. Titan also has an antigreenhouse effect due to a high-altitude haze layer which absorbs at solar wavelengths, while remaining transparent in the thermal IR; if this haze layer were removed, the antigreenhouse effect would be greatly reduced, exacerbating the greenhouse effect and raising surface temperature by over 20 K.

  11. The contribution of phenotypic plasticity to complementary light capture in plant mixtures.

    Science.gov (United States)

    Zhu, Junqi; van der Werf, Wopke; Anten, Niels P R; Vos, Jan; Evers, Jochem B

    2015-09-01

    Interspecific differences in functional traits are a key factor for explaining the positive diversity-productivity relationship in plant communities. However, the role of intraspecific variation attributable to phenotypic plasticity in diversity-productivity relationships has largely been overlooked. By taking a wheat (Triticum aestivum)-maize (Zea mays) intercrop as an elementary example of mixed vegetation, we show that plasticity in plant traits is an important factor contributing to complementary light capture in species mixtures. We conceptually separated net biodiversity effect into the effect attributable to interspecific trait differences and species distribution (community structure effect), and the effect attributable to phenotypic plasticity. Using a novel plant architectural modelling approach, whole-vegetation light capture was simulated for scenarios with and without plasticity based on empirical plant trait data. Light capture was 23% higher in the intercrop with plasticity than the expected value from monocultures, of which 36% was attributable to community structure and 64% was attributable to plasticity. For wheat, plasticity in tillering was the main reason for increased light capture, whereas for intercropped maize, plasticity induced a major reduction in light capture. The results illustrate the potential of plasticity for enhancing resource acquisition in mixed stands, and indicate the importance of plasticity in the performance of species-diverse plant communities.

  12. Terrestrial transect study on driving mechanism of vegetation changes

    Institute of Scientific and Technical Information of China (English)

    ZHANG YuJin; ZHOU GuangSheng

    2008-01-01

    In terms of Chinese climate-vegetation model based on the classification of plant functional types,together with climatic data from 1951 to 1980 and two future climatic scenarios (SRES-A2 and SRES-B2)in China from the highest and the lowest emission scenarios of greenhouse gases,the distribution patterns of vegetation types and their changes along the Northeast China Transect (NECT) and the North-South Transect of Eastern China (NSTEC) were simulated in order to understand the driving mechanisms of vegetation changes under climatic change. The results indicated that the vegetation distribution patterns would change significantly under future climate,and the major factors driving the vegetation changes were water and heat. However,the responses of various vegetation types to the changes in water and heat factors were obviously different. The vegetation changes were more sensitive to heat factors than to water factors. Thus,in the future climate warming will significantly affect vegetation distribution patterns.

  13. Greenhouse Trace Gases in Deadwood

    Science.gov (United States)

    Covey, Kristofer; Bueno de Mesquita, Cliff; Oberle, Brad; Maynard, Dan; Bettigole, Charles; Crowther, Thomas; Duguid, Marlyse; Steven, Blaire; Zanne, Amy; Lapin, Marc; Ashton, Mark; Oliver, Chad; Lee, Xuhui; Bradford, Mark

    2016-04-01

    Deadwood, long recognized as playing an important role in carbon cycling in forest ecosystems, is more recently drawing attention for its potential role in the cycling of other greenhouse trace gases. We report data from four independent studies measuring internal gas concentrations in deadwood in in three Quercus dominated upland forest systems in the Northeastern and Central United States. Mean methane concentrations in deadwood were 23 times atmospheric levels, indicating a lower bound, mean radial wood surface area flux of ~6 x 10-4 μmol CH4 m-2 s-1. Site, decay class, diameter, and species were all highly significant predictors of methane abundance in deadwood, and log diameter and decay stage interacted as important controls limiting methane concentrations in the smallest and most decayed logs. Nitrous oxide concentrations were negatively correlated with methane and on average ~25% lower than ambient, indicating net consumption of nitrous oxide. These data suggest nonstructural carbohydrates fuel archaeal methanogens and confirm the potential for widespread in situ methanogenesis in both living and deadwood. Applying this understanding to estimate methane emissions from microbial activity in living trees implies a potential global flux of 65.6±12.0 Tg CH4 yr-1, more than 20 times greater than currently considered.

  14. Greenhouse gas mitigation in agriculture.

    Science.gov (United States)

    Smith, Pete; Martino, Daniel; Cai, Zucong; Gwary, Daniel; Janzen, Henry; Kumar, Pushpam; McCarl, Bruce; Ogle, Stephen; O'Mara, Frank; Rice, Charles; Scholes, Bob; Sirotenko, Oleg; Howden, Mark; McAllister, Tim; Pan, Genxing; Romanenkov, Vladimir; Schneider, Uwe; Towprayoon, Sirintornthep; Wattenbach, Martin; Smith, Jo

    2008-02-27

    Agricultural lands occupy 37% of the earth's land surface. Agriculture accounts for 52 and 84% of global anthropogenic methane and nitrous oxide emissions. Agricultural soils may also act as a sink or source for CO2, but the net flux is small. Many agricultural practices can potentially mitigate greenhouse gas (GHG) emissions, the most prominent of which are improved cropland and grazing land management and restoration of degraded lands and cultivated organic soils. Lower, but still significant mitigation potential is provided by water and rice management, set-aside, land use change and agroforestry, livestock management and manure management. The global technical mitigation potential from agriculture (excluding fossil fuel offsets from biomass) by 2030, considering all gases, is estimated to be approximately 5500-6000Mt CO2-eq.yr-1, with economic potentials of approximately 1500-1600, 2500-2700 and 4000-4300Mt CO2-eq.yr-1 at carbon prices of up to 20, up to 50 and up to 100 US$ t CO2-eq.-1, respectively. In addition, GHG emissions could be reduced by substitution of fossil fuels for energy production by agricultural feedstocks (e.g. crop residues, dung and dedicated energy crops). The economic mitigation potential of biomass energy from agriculture is estimated to be 640, 2240 and 16 000Mt CO2-eq.yr-1 at 0-20, 0-50 and 0-100 US$ t CO2-eq.-1, respectively.

  15. [Effects of soil covering on solar greenhouse pepper water use efficiency and soil nitrate N and available phosphorus contents].

    Science.gov (United States)

    Zhou, Mao-juan; Liang, Yin-li; Chen, Jia-rui; Xiong, Ya-mei; Wei, Ze-xiu

    2007-06-01

    A greenhouse study on the effects of soil covering on pepper (Capsicum anmuum L.) water use efficiency and soil nitrate and available phosphorus contents showed that straw mulch + plastic film mulch could get the highest pepper yield water use efficiency (33.04 kg . m(-3)) and economic water use efficiency (50.22 yuan . m(-3)), followed by plastic film mulch, with the two parameters being 18.81 kg . m(-3) and 28.57 yuan . m(-3), respectively. Significant differences of nitrate N content in 0-20 cm soil layer were observed among different treatments. The control had the highest nitrate N content (50.33 mg . kg(-1)), followed by straw mulch (31.98 mg . kg(-1)) and straw + plastic film mulch (31.96 mg . kg(-1)), and plastic film mulch and applying water preserving agent. Compared with the control, soil covering could increase the nitrate N use efficiency of pepper, and decrease the accumulation of nitrate N in plough layer. In 0-20 cm soil layer, treatment plastic film mulch had the lowest available phosphorus content (0.72 mg . kg(-3)), and the second (0. 92 mg . kg(-1)) was the treatment straw + plastic film mulch. Treatments straw + plastic film mulch and plastic film mulch could increase pepper fruit yield and fertilizer use efficiency, and decrease fertilizer loss.

  16. Informative document waste plastics

    NARCIS (Netherlands)

    Nagelhout D; Sein AA; Duvoort GL

    1989-01-01

    This "Informative document waste plastics" forms part of a series of "informative documents waste materials". These documents are conducted by RIVM on the indstruction of the Directorate General for the Environment, Waste Materials Directorate, in behalf of the program of

  17. A Plastic Menagerie

    Science.gov (United States)

    Hadley, Mary Jane

    2010-01-01

    Bobble heads had become quite popular, depicting all sorts of sports figures, animals, and even presidents. In this article, the author describes how her fourth graders made bobble head sculptures out of empty plastic drink bottles. (Contains 1 online resource.)

  18. Cortical plasticity and rehabilitation.

    Science.gov (United States)

    Moucha, Raluca; Kilgard, Michael P

    2006-01-01

    The brain is constantly adapting to environmental and endogenous changes (including injury) that occur at every stage of life. The mechanisms that regulate neural plasticity have been refined over millions of years. Motivation and sensory experience directly shape the rewiring that makes learning and neurological recovery possible. Guiding neural reorganization in a manner that facilitates recovery of function is a primary goal of neurological rehabilitation. As the rules that govern neural plasticity become better understood, it will be possible to manipulate the sensory and motor experience of patients to induce specific forms of plasticity. This review summarizes our current knowledge regarding factors that regulate cortical plasticity, illustrates specific forms of reorganization induced by control of each factor, and suggests how to exploit these factors for clinical benefit.

  19. Mechanical plasticity of cells

    Science.gov (United States)

    Bonakdar, Navid; Gerum, Richard; Kuhn, Michael; Spörrer, Marina; Lippert, Anna; Schneider, Werner; Aifantis, Katerina E.; Fabry, Ben

    2016-10-01

    Under mechanical loading, most living cells show a viscoelastic deformation that follows a power law in time. After removal of the mechanical load, the cell shape recovers only incompletely to its original undeformed configuration. Here, we show that incomplete shape recovery is due to an additive plastic deformation that displays the same power-law dynamics as the fully reversible viscoelastic deformation response. Moreover, the plastic deformation is a constant fraction of the total cell deformation and originates from bond ruptures within the cytoskeleton. A simple extension of the prevailing viscoelastic power-law response theory with a plastic element correctly predicts the cell behaviour under cyclic loading. Our findings show that plastic energy dissipation during cell deformation is tightly linked to elastic cytoskeletal stresses, which suggests the existence of an adaptive mechanism that protects the cell against mechanical damage.

  20. Targeting tumour Cell Plasticity

    Institute of Scientific and Technical Information of China (English)

    Elizabeth D. WILLIAMS

    2009-01-01

    @@ Her research is focused on understanding the mechanisms of tumour progression and metastasis, particularly in uro-logical carcinomas (bladder and prostate). Tumour cell plasticity, including epithelial-mesenchymal transition, is a cen-tral theme in Dr Williams' work.

  1. Generalized Software Architecture Applied to the Continuous Lunar Water Separation Process and the Lunar Greenhouse Amplifier

    Science.gov (United States)

    Perusich, Stephen; Moos, Thomas; Muscatello, Anthony

    2011-01-01

    This innovation provides the user with autonomous on-screen monitoring, embedded computations, and tabulated output for two new processes. The software was originally written for the Continuous Lunar Water Separation Process (CLWSP), but was found to be general enough to be applicable to the Lunar Greenhouse Amplifier (LGA) as well, with minor alterations. The resultant program should have general applicability to many laboratory processes (see figure). The objective for these programs was to create a software application that would provide both autonomous monitoring and data storage, along with manual manipulation. The software also allows operators the ability to input experimental changes and comments in real time without modifying the code itself. Common process elements, such as thermocouples, pressure transducers, and relative humidity sensors, are easily incorporated into the program in various configurations, along with specialized devices such as photodiode sensors. The goal of the CLWSP research project is to design, build, and test a new method to continuously separate, capture, and quantify water from a gas stream. The application is any In-Situ Resource Utilization (ISRU) process that desires to extract or produce water from lunar or planetary regolith. The present work is aimed at circumventing current problems and ultimately producing a system capable of continuous operation at moderate temperatures that can be scaled over a large capacity range depending on the ISRU process. The goal of the LGA research project is to design, build, and test a new type of greenhouse that could be used on the moon or Mars. The LGA uses super greenhouse gases (SGGs) to absorb long-wavelength radiation, thus creating a highly efficient greenhouse at a future lunar or Mars outpost. Silica-based glass, although highly efficient at trapping heat, is heavy, fragile, and not suitable for space greenhouse applications. Plastics are much lighter and resilient, but are not

  2. LOADS INTERACTION DOMAINS METHODOLOGY FOR THE DESIGN OF STEEL GREENHOUSE STRUCTURES

    Directory of Open Access Journals (Sweden)

    Sergio Castellano

    2007-03-01

    Full Text Available Aim of this research is to develop a design methodology which correlates main structural design parameters, whose production is characterised by high levels of standardization, such as the height of gutter or the distance between frames, with actions on the greenhouse. The methodology, based on the use of charts and abacus, permits a clear and a direct interpretation of the structural response to design load combinations and allows the design of structural improvements with the aim of the optimization of the ratio benefits (structural strength/costs. The study of structural interaction domains allowed a clear and a direct interpretation of the structural response to design load combinations. The diagrams highlight not only if the structure fulfils the standard requirements but also the safety levels with respect to design load combinations and allow the structural designer how to operate in order to optimize the structural response with standard requirements achieving the best ratio benefits (structural safety/ costs. The methodology was developed basing on criteria assigned by EN13031 on two different kinds of greenhouse structures: an arched greenhouse with a film plastic covering and a duo pitched roof greenhouse cover with rigid plastic membranes. Structural interaction domains for arched greenhouse showed a better capability of the structure to resist to vertical loads then to horizontal one. Moreover, the climatic load distribution on the structure assigned by EN13031 is such that the combination of climatic actions is less dangerous for the structure then their individual application. Whilst, duo pitched roof steel greenhouse interaction domains, showed a better capability of the structure to resist to vertical loads then to horizontal one and that, in any case, the serviceability limit states analysis is more strict then the ULS one. The shape of structural domains highlighted that the combination of actions is more dangerous for the

  3. Laser cutting plastic materials

    Energy Technology Data Exchange (ETDEWEB)

    Van Cleave, R.A.

    1980-08-01

    A 1000-watt CO/sub 2/ laser has been demonstrated as a reliable production machine tool for cutting of plastics, high strength reinforced composites, and other nonmetals. More than 40 different plastics have been laser cut, and the results are tabulated. Applications for laser cutting described include fiberglass-reinforced laminates, Kevlar/epoxy composites, fiberglass-reinforced phenolics, nylon/epoxy laminates, ceramics, and disposable tooling made from acrylic.

  4. Localization of plastic deformation

    Energy Technology Data Exchange (ETDEWEB)

    Rice, J R

    1976-04-01

    The localization of plastic deformation into a shear band is discussed as an instability of plastic flow and a precursor to rupture. Experimental observations are reviewed, a general theoretical framework is presented, and specific calculations of critical conditions are carried out for a variety of material models. The interplay between features of inelastic constitutive description, especially deviations from normality and vertex-like yielding, and the onset of localization is emphasized.

  5. Solar greenhouse training project. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Davis, L.; Kensil, D.; Lazar, B.; Yanda, B.; Yanda, S.

    1979-04-01

    The goals of this project were: (1) To train twenty teams, each from a different region, to organize and run workshops to build inexpensive, practical solar greenhouses. (2) To help create working solar greenhouse experts in the field available to respond to their community's needs. (3) To establish a national model program for solar greenhouse construction workshops. (4) To determine whether the barn-raising style used in the greenhouse construction workshops could be taught in the format of a 3 1/2 day seminar with a follow-up workshop. (5) To determine whether the audio-visual exhibit and printed materials used in the seminar were effective. (MOW)

  6. Goniometric characterization of LED based greenhouse lighting

    DEFF Research Database (Denmark)

    Thorseth, Anders; Lindén, Johannes; Corell, Dennis Dan

    2015-01-01

    This paper describes a demonstration of goniospectroradiometry for characterizations of new light emitting diode (LED) based luminaries for enhanced photosynthesis in greenhouses. It highlights the differences between measurement of the traditional high pressure sodium (HPS) luminaries and the LED...

  7. A new opinion of the greenhouse effect

    Directory of Open Access Journals (Sweden)

    Valery P. Oktyabrskiy

    2016-06-01

    Full Text Available The article analyzes the correspondence between the actually occurring physical and chemical processes and the concept of the greenhouse effect. The absorption of the solar radiation by the gases existing in the Earth's atmosphere has been examined. It was demonstrated that, despite the absorption of radiation from the Earth's surface in the middle and long-wave infrared (IR regions, there is a strong absorption of the overtones and combined frequencies of water vapor in the solar radiation (visible and near IR regions, i.e., the transmittance bandwidth of ‘the glass greenhouse’. Thus, the Earth atmosphere does not really function as a greenhouse, and the terms ‘greenhouse effect’ and ‘greenhouse gases’ lost their original meaning and have remained symbolical.

  8. Greenhouse Modeling Using Continuous Timed Petri Nets

    Directory of Open Access Journals (Sweden)

    José Luis Tovany

    2013-01-01

    Full Text Available This paper presents a continuous timed Petri nets (ContPNs based greenhouse modeling methodology. The presented methodology is based on the definition of elementary ContPN modules which are designed to capture the components of a general energy and mass balance differential equation, like parts that are reducing or increasing variables, such as heat, CO2 concentration, and humidity. The semantics of ContPN is also extended in order to deal with variables depending on external greenhouse variables, such as solar radiation. Each external variable is represented by a place whose marking depends on an a priori known function, for instance, the solar radiation function of the greenhouse site, which can be obtained statistically. The modeling methodology is illustrated with a greenhouse modeling example.

  9. Arctic climate change: Greenhouse warming unleashed

    Science.gov (United States)

    Mauritsen, Thorsten

    2016-04-01

    Human activity alters the atmospheric composition, which leads to global warming. Model simulations suggest that reductions in emission of sulfur dioxide from Europe since the 1970s could have unveiled rapid Arctic greenhouse gas warming.

  10. The Greenhouse Effect in a Vial.

    Science.gov (United States)

    Golden, Richard; Sneider, Cary

    1989-01-01

    Presents an example of a greenhouse-effect experiment from the Climate Protection Institute. Analyzes the amount of carbon dioxide in ambient air, human exhalation, automobile exhaust, and nearly pure carbon dioxide by titrating with ammonia and bromthymol blue. (MVL)

  11. Reservoir Greenhouse Gas Emissions at Russian HPP

    Energy Technology Data Exchange (ETDEWEB)

    Fedorov, M. P.; Elistratov, V. V.; Maslikov, V. I.; Sidorenko, G. I.; Chusov, A. N.; Atrashenok, V. P.; Molodtsov, D. V. [St. Petersburg State Polytechnic University (Russian Federation); Savvichev, A. S. [Russian Academy of Sciences, S. N. Vinogradskii Institute of Microbiology (Russian Federation); Zinchenko, A. V. [A. I. Voeikov Main Geophysical Observatory (Russian Federation)

    2015-05-15

    Studies of greenhouse-gas emissions from the surfaces of the world’s reservoirs, which has demonstrated ambiguity of assessments of the effect of reservoirs on greenhouse-gas emissions to the atmosphere, is analyzed. It is recommended that greenhouse- gas emissions from various reservoirs be assessed by the procedure “GHG Measurement Guidelines for Fresh Water Reservoirs” (2010) for the purpose of creating a data base with results of standardized measurements. Aprogram for research into greenhouse-gas emissions is being developed at the St. Petersburg Polytechnic University in conformity with the IHA procedure at the reservoirs impounded by the Sayano-Shushenskaya and Mainskaya HPP operated by the RusHydro Co.

  12. Greenhouses for food production and the environment

    Directory of Open Access Journals (Sweden)

    Abdeen Mustafa Omer

    2016-01-01

    Full Text Available A greenhouse is essentially an enclosed structure, which traps the short wavelength solar radiation and stores the long wavelength thermal radiation to create a favourable microclimate for higher productivity. The sun’s radiation incident on the greenhouse has two parts: direct radiation and an associated diffuse sky radiation. The diffuse part is not focused by the lenses and goes right through Frensel lenses onto the surface of the absorbers. This energy is absorbed and transformed into heat, which is then transported via the liquid medium in copper pipes to the water (heat storage tanks or, if used, open fish tanks. In this way, an optimal temperature for both plant cultivation and fish production can be maintained. Stable plant growth conditions are light, temperature and air humidity. Light for the photosynthesis of plants comes from the diffuse radiation, which is without substantial fluctuations and variation throughout most of the day. The air temperature inside the greenhouse is one of the factors that have an influence on the precocity of production. The selective collector acts in a more perceptible way on extreme air temperatures inside the greenhouse. Hence, the system makes it possible to avoid the excessive deviation of the temperature inside the greenhouse and provides a favourable microclimate for the precocity of the culture. Sediment and some associated water from the sediment traps are used as organic fertiliser for the plant cultivation. The present trend in greenhouse cultivation is to extend the crop production season in order to maximise use of the equipment and increase annual productivity and profitability. However, in many Mediterranean greenhouses, such practices are limited because the improper cooling methods (mainly natural or forced ventilation used do not provide the desired micro-climatic condition during the summer of a composite climate. Also, some of these greenhouses have been built where the

  13. Voluntary reporting of greenhouse gases, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-07-01

    The Voluntary Reporting Program for greenhouse gases is part of an attempt by the U.S. Government to develop innovative, low-cost, and nonregulatory approaches to limit emissions of greenhouse gases. It is one element in an array of such programs introduced in recent years as part of the effort being made by the United States to comply with its national commitment to stabilize emissions of greenhouse gases under the Framework Convention on Climate Change. The Voluntary Reporting Program, developed pursuant to Section 1605(b) of the Energy Policy Act of 1992, permits corporations, government agencies, households, and voluntary organizations to report to the Energy Information Administration (EIA) on actions taken that have reduced or avoided emissions of greenhouse gases.

  14. Multiagency Initiative to Provide Greenhouse Gas Information

    Science.gov (United States)

    Boland, Stacey W.; Duren, Riley M.

    2009-11-01

    Global Greenhouse Gas Information System Workshop; Albuquerque, New Mexico, 20-22 May 2009; The second Greenhouse Gas Information System (GHGIS) workshop brought together 74 representatives from 28 organizations including U.S. government agencies, national laboratories, and members of the academic community to address issues related to the understanding, operational monitoring, and tracking of greenhouse gas emissions and carbon offsets. The workshop was held at Sandia National Laboratories and organized by an interagency collaboration among NASA centers, Department of Energy laboratories, and the U.S. National Oceanic and Atmospheric Administration. It was motivated by the perceived need for an integrated interagency, community-wide initiative to provide information about greenhouse gas sources and sinks at policy-relevant temporal and spatial scales. Such an initiative could significantly enhance the ability of national and regional governments, industry, and private citizens to implement and evaluate effective climate change mitigation policies.

  15. Greenhouse climate model : an aid to estimate the influence of supplemental lighting on greenhouse climate

    OpenAIRE

    Binotto, Marco 1987

    2012-01-01

    GeoGreenhouse project involves the construction of a greenhouse for growing tomatoes in Iceland. The first stage consists of a gross area of five hectares. Due to the peculiarities of such project and because of the unique weather, a greenhouse climate model is advisable to analyze various design solutions. Iceland's weather has a seasonal change in the length of day and night, creating unique weather phenomena. In midwinter, there is a period where darkness prevails. In midsummer, dayligh...

  16. Development of plastic surgery

    Directory of Open Access Journals (Sweden)

    Pećanac Marija Đ.

    2015-01-01

    Full Text Available Introduction. Plastic surgery is a medical specialty dealing with corrections of defects, improvements in appearance and restoration of lost function. Ancient Times. The first recorded account of reconstructive plastic surgery was found in ancient Indian Sanskrit texts, which described reconstructive surgeries of the nose and ears. In ancient Greece and Rome, many medicine men performed simple plastic cosmetic surgeries to repair damaged parts of the body caused by war mutilation, punishment or humiliation. In the Middle Ages, the development of all medical braches, including plastic surgery was hindered. New age. The interest in surgical reconstruction of mutilated body parts was renewed in the XVIII century by a great number of enthusiastic and charismatic surgeons, who mastered surgical disciplines and became true artists that created new forms. Modern Era. In the XX century, plastic surgery developed as a modern branch in medicine including many types of reconstructive surgery, hand, head and neck surgery, microsurgery and replantation, treatment of burns and their sequelae, and esthetic surgery. Contemporary and future plastic surgery will continue to evolve and improve with regenerative medicine and tissue engineering resulting in a lot of benefits to be gained by patients in reconstruction after body trauma, oncology amputation, and for congenital disfigurement and dysfunction.

  17. Bibliography of greenhouse-gas reduction strategies

    Energy Technology Data Exchange (ETDEWEB)

    Tompkins, M.M.; Mintz, M.M.

    1995-03-01

    A bibliography of greenhouse-gas reduction strategies has been compiled to assist the Climate change Action Plan Task Force in their consideration of strategies to reduce greenhouse-gas emissions from personal motor vehicles. The document contains a summary of the literature, including it major directions and implications; and annotated listing of 32 recent pertinent documents; and a listing of a larger group of related reports.

  18. Sorting Plastic Waste in Hydrocyclone

    Directory of Open Access Journals (Sweden)

    Ernestas Šutinys

    2011-02-01

    Full Text Available The article presents material about sorting plastic waste in hydrocyclone. The tests on sorting plastic waste were carried out. Also, the findings received from the performed experiment on the technology of sorting plastic waste are interpreted applying an experimental model of the equipment used for sorting plastics of different density.Article in Lithuanian

  19. Thyroid function in Danish greenhouse workers

    Directory of Open Access Journals (Sweden)

    Bonde Jens

    2006-12-01

    Full Text Available Abstract Background From animal studies it is known that currently used pesticides can disturb thyroid function. Methods In the present study we investigated the thyroid function in 122 Danish greenhouse workers, to evaluate if greenhouse workers classified as highly exposed to pesticides experiences altered thyroid levels compared to greenhouse workers with lower exposure. Serum samples from the greenhouse workers were sampled both in the spring and the fall to evaluate if differences in pesticide use between seasons resulted in altered thyroid hormone levels. Results We found a moderate reduction of free thyroxine (FT4 (10–16% among the persons working in greenhouses with a high spraying load both in samples collected in the spring and the fall, but none of the other measured thyroid hormones differed significantly between exposure groups in the cross-sectional comparisons. However, in longitudinal analysis of the individual thyroid hormone level between the spring and the fall, more pronounced differences where found with on average 32% higher thyroid stimulating hormone (TSH level in the spring compared to the fall and at the same time a 5–9% lower total triiodthyroxin (TT3, free triiodthyroxine (FT3 and FT4. The difference between seasons was not consistently more pronounced in the group classified as high exposure compared to the low exposure groups. Conclusion The present study indicates that pesticide exposure among Danish greenhouse workers results in only minor disturbances of thyroid hormone levels.

  20. Computer Controlled Portable Greenhouse Climate Control System for Enhanced Energy Efficiency

    Science.gov (United States)

    Datsenko, Anthony; Myer, Steve; Petties, Albert; Hustek, Ryan; Thompson, Mark

    2010-04-01

    This paper discusses a student project at Kettering University focusing on the design and construction of an energy efficient greenhouse climate control system. In order to maintain acceptable temperatures and stabilize temperature fluctuations in a portable plastic greenhouse economically, a computer controlled climate control system was developed to capture and store thermal energy incident on the structure during daylight periods and release the stored thermal energy during dark periods. The thermal storage mass for the greenhouse system consisted of a water filled base unit. The heat exchanger consisted of a system of PVC tubing. The control system used a programmable LabView computer interface to meet functional specifications that minimized temperature fluctuations and recorded data during operation. The greenhouse was a portable sized unit with a 5' x 5' footprint. Control input sensors were temperature, water level, and humidity sensors and output control devices were fan actuating relays and water fill solenoid valves. A Graphical User Interface was developed to monitor the system, set control parameters, and to provide programmable data recording times and intervals.

  1. Greenhouse gases emission from municipal waste management: The role of separate collection.

    Science.gov (United States)

    Calabrò, Paolo S

    2009-07-01

    The municipal solid waste management significantly contributes to the emission in the atmosphere of greenhouse gases (e.g. CO(2), CH(4), N(2)O) and therefore the management process from collection to treatment and disposal has to be optimized in order to reduce these emissions. In this paper, starting from the average composition of undifferentiated municipal solid waste in Italy, the effect of separate collection on greenhouse gases emissions from municipal waste management has been assessed. Different combinations of separate collection scenarios and disposal options (i.e. landfilling and incineration) have been considered. The effect of energy recovery from waste both in landfills and incinerators has also been addressed. The results outline how a separate collection approach can have a significant effect on the emission of greenhouse gases and how wise municipal solid waste management, implying the adoption of Best Available Technologies (i.e. biogas recovery and exploitation system in landfills and energy recovery system in Waste to Energy plants), can not only significantly reduce greenhouse gases emissions but, in certain cases, can also make the overall process a carbon sink. Moreover it has been shown that separate collection of plastic is a major issue when dealing with global warming relevant emissions from municipal solid waste management.

  2. The Semitransparent Photovoltaic Films for Mediterranean Greenhouse: A New Sustainable Technology

    Directory of Open Access Journals (Sweden)

    Alvaro Marucci

    2012-01-01

    Full Text Available Mediterranean countries offer very favorable climatic conditions for growing plants in a protected environment: as a matter of fact, the high solar radiation allows the use of greenhouses with simple structures, covered with plastic film and without fixed installations for winter heating. They are called “Mediterranean greenhouses” and are totally different from those in Central and Northern Europe. In the photovoltaic greenhouses, the cover on the pitch facing south is usually replaced by very opaque panels. However, this solution compromises the possibility to grow plants in covered and protected environments since solar radiation availability is limited and strongly nonuniform. In order to overcome this problem, semitransparent photovoltaic materials can be used to let the solar energy, necessary for plant growth, pass into the green house. The aim of this research is to analyze the radiometric properties of innovative semitransparent flexible photovoltaic materials in order to evaluate their performances in comparison with materials commonly used in the coverage of the greenhouses. Particular attention is paid to the transmittance of these materials in the visible range and in the long wave infrared for the achievement of greenhouse effect.

  3. Analysis of Factors Affecting the Demand for Beijing Policy Vegetable Insurance-Based on a Survey on Vegetable Growers%北京市政策性蔬菜保险需求的影响因素分析--基于对蔬菜种植户的调研

    Institute of Scientific and Technical Information of China (English)

    孟阳; 穆月英

    2013-01-01

    以Von Neumann-Morgenstern效用理论为基础,采用实际调研数据,通过Logit离散选择模型分析农户对北京市政策性蔬菜保险需求的影响因素,研究结果表明:是否有外出务工人员、设施蔬菜生产的年限、农业风险对农户生产生活的影响、农户对温室和大棚保险的了解程度以及风险规避手段的数量均对农户购买温室、大棚保险的意愿有显著性影响。其中,前两个因素对购买意愿的影响是负向的,而后三个因素则起正向作用。最后提出促进北京市政策性蔬菜保险发展的政策建议。%Based on the Von Neumann-Morgenstern utility theory,this paper used the actual survey data,and analyzed the influencing factors for Beijing policy vegetable insurance demand by Logit model. The results showed that whether there were migrant workers,the number of fixed years for facility vegetable production,impact of agricultural risks to farm household production and life,farm households’understanding about insurance of greenhouse and plastic shed,and the number of risk aversion means had significant impact on farm households’wishs to purchase greenhouse and plastic shed insurance. Among them,the first 2 factors have negative influence on their purchasing intention;while,the later 3 factors have positive effects. Finally the paper put forward policy suggestions to promote the development of policy vegetable insurance in Beijing.

  4. An overview of climate and crop yield in closed greenhouses

    NARCIS (Netherlands)

    Gelder, de A.; Dieleman, J.A.; Bot, G.P.A.; Marcelis, L.F.M.

    2012-01-01

    The closed greenhouse is a recent innovation in the horticulture industry. Cooling by ventilation is replaced partly (in semi-closed greenhouses) or completely (in closed greenhouses) by mechanical cooling. Excess solar energy is collected and stored to be reused to heat the greenhouse. In temperate

  5. Development of concepts for a zero-fossil-energy greenhouse

    NARCIS (Netherlands)

    Ooster, A. van 't; Henten, E.J. van; Janssen, E.G.O.N.; Bot, G.P.A.; Dekker, E.

    2008-01-01

    Dutch government and greenhouse horticultural practice aim for strongly reduced fossil energy use and of environmental loads in 2010 and energy neutral greenhouses in 2020. This research aims to design a greenhouse concept with minimal use of fossil energy and independent of nearby greenhouses. The

  6. Development of concepts for a zero-fossil-energy greenhouse

    NARCIS (Netherlands)

    Ooster, A. van 't; Henten, E.J. van; Janssen, E.G.O.N.; Bot, G.P.A.; Dekker, E.

    2008-01-01

    Dutch government and greenhouse horticultural practice aim for strongly reduced fossil energy use and of environmental loads in 2010 and energy neutral greenhouses in 2020. This research aims to design a greenhouse concept with minimal use of fossil energy and independent of nearby greenhouses. The

  7. A Note on Fourier and the Greenhouse Effect

    CERN Document Server

    Postma, Joseph E

    2015-01-01

    Joseph Fourier's discovery of the greenhouse effect is discussed and is compared to the modern conception of the greenhouse effect. It is confirmed that what Fourier discovered is analogous to the modern concept of the greenhouse effect. However, the modern concept of the greenhouse effect is found to be based on a paradoxical analogy to Fourier's greenhouse work and so either Fourier's greenhouse work, the modern conception of the greenhouse effect, or the modern definition of heat is incorrect. The solution to this problem is not feigned to be given here.

  8. Dissipation of chlorpyrifos on pakchoi inside and outside greenhouse

    Institute of Scientific and Technical Information of China (English)

    YU Yun-long; FANG Hua; WANG Xiao; YU Jing-quan; FAN De-fang

    2005-01-01

    The dissipation of chlorpyrifos on pakchoi inside and outside greenhouse was studied. The decline curve of chlorpyrifos on pakchoi could be described as first-order kinetic. The experimental data showed that both the hermetic environment of greenhouse and season affected dissipation rates of chlorpyrifos on pakchoi. Chlorpyrifos declined faster outside greenhouse than inside greenhouse.Chlorpyrifos residues at pre-harvest time were below the maximum residue limits (MRLs) fixed in China, whereas the values inside greenhouse were higher than those outside greenhouse by almost 50%. The recommended pre-harvest time established under conditions of open field might not always fit to greenhouse production.

  9. Space and time variability of heating requirements for greenhouse tomato production in the Euro-Mediterranean area.

    Science.gov (United States)

    Mariani, Luigi; Cola, Gabriele; Bulgari, Roberta; Ferrante, Antonio; Martinetti, Livia

    2016-08-15

    The Euro-Mediterranean area is the seat of a relevant greenhouse activity, meeting the needs of important markets. A quantitative assessment of greenhouse energy consumption and of its variability in space and time is an important decision support tool for both greenhouse-sector policies and farmers. A mathematical model of greenhouse energy balance was developed and parameterized for a state-of-the-art greenhouse to evaluate the heating requirements for vegetables growing. Tomato was adopted as reference crop, due to its high energy requirement for fruit setting and ripening and its economic relevance. In order to gain a proper description of the Euro-Mediterranean area, 56 greenhouse areas located within the ranges 28°N-72°N and 11°W-55°E were analyzed over the period 1973-2014. Moreover, the two 1973-1987 and 1988-2014 sub-periods were separately studied to describe climate change effects on energy consumption. Results account for the spatial variability of energy needs for tomato growing, highlighting the strong influence of latitude on the magnitude of heat requirements. The comparison between the two selected sub-periods shows a decrease of energy demand in the current warm phase, more relevant for high latitudes. Finally, suggestions to reduce energy consumptions are provided.

  10. Storage built pebble bed for greenhouse use; Acumulador tipo lecho para uso en invernaderos

    Energy Technology Data Exchange (ETDEWEB)

    Bistoni, S.; Iriarte, A.; Saravia, L.

    2004-07-01

    To heat greenhouses during the night it is necessary to use storage systems. Our region shows high radiation levels, even in winter, so during the day stored energy inside of a greenhouse is more than necessary. If the excess of energy is stored up, it can be used during the night when it is necessary. In this paper the performance of a storage built with plastic bottles with water inside them are studied and it is compared with a pebble bed. A model and its solution using the electric- thermal analogy are presented. The results show that it is feasible and economic to build a storage like the proposed. It is important to mention that the simulation is very simple because of the computational program used. (Author)

  11. A novel biobased polyester plasticizer prepared from palm oil and its plasticizing effect on poly (vinyl chloride

    Directory of Open Access Journals (Sweden)

    Jia Puyou

    2016-03-01

    Full Text Available In this study, palm oil was the first time to convert into a novel polyester plasticizer for polyvinyl chloride (PVC. In the first stage, palm oil was converted into palm oil monoglyceride (POM by alcoholysis with glycerol. Next, a novel palm oil monoglycerides based polyester plasticizer (POMP was synthesized from POM and maleic anhydride through esterification and condensation reaction. The structure of POMP was characterized with FTIR, 1H NMR and GPC. Then PVC blends were prepared using POMP as a plasticizer, melting behavior, thermal property, compatibility, mechanical properties and mechanism of plasticization of PVC blends were systematically studied. Melting behavior indicated that POMP could decrease the torque and the melt viscosity of PVC blends that was conducive to process. With the content of POMP increasing from 5 g to 15 g in PVC blends, the plasticized PVC blends demonstrated better compatibility, the degradation temperature (Td increased from 252.6°C to 257.0°C, the glass transition temperature (Tg decreased from 55°C to 49.5°C. Plasticization was put into effect by interaction of the electron cloud between the PVC chain and POMP molecule. This study may lead to the development of new type of PVC plasticizer based on vegetable oil.

  12. Comparison of three trap types for adult catching of whitefly Bemisia tabaci and its parasitoid Eretmocerus mundus in tomato greenhouse

    OpenAIRE

    Nombela, Gloria; Chu, CC.; Heneberry, T.; Muñiz, M.

    2003-01-01

    The attractiveness of three trap types to Bemisia tabaci (Gennadius) B-biotype (= Bemisia argentifolii Bellows & Perring) and Eretmocerus mundus Mercet adult was compared in two choice experiments in a greenhouse at the Centro de Ciencias Medioambientales, Madrid, Spain.  Yellow sticky cards equipped with light-emitting-diodes (LED-YC) caught more adults per trap per day than yellow sticky card (YC) traps.YC traps caught significantly more B. tabaci and E. mundus adults than plastic cup traps...

  13. Greenhouse-gas-trading markets.

    Science.gov (United States)

    Sandor, Richard; Walsh, Michael; Marques, Rafael

    2002-08-15

    This paper summarizes the extension of new market mechanisms for environmental services, explains of the importance of generating price information indicative of the cost of mitigating greenhouse gases (GHGs) and presents the rationale and objectives for pilot GHG-trading markets. It also describes the steps being taken to define and launch pilot carbon markets in North America and Europe and reviews the key issues related to incorporating carbon sequestration into an emissions-trading market. There is an emerging consensus to employ market mechanisms to help address the threat of human-induced climate changes. Carbon-trading markets are now in development around the world. A UK market is set to launch in 2002, and the European Commission has called for a 2005 launch of an European Union (EU)-wide market, and a voluntary carbon market is now in formation in North America. These markets represent an initial step in resolving a fundamental problem in defining and implementing appropriate policy actions to address climate change. Policymakers currently suffer from two major information gaps: the economic value of potential damages arising from climate changes are highly uncertain, and there is a lack of reliable information on the cost of mitigating GHGs. These twin gaps significantly reduce the quality of the climate policy debate. The Chicago Climate Exchange, for which the authors serve as lead designers, is intended to provide an organized carbon-trading market involving energy, industry and carbon sequestration in forests and farms. Trading among these diverse sectors will provide price discovery that will help clarify the cost of combating climate change when a wide range of mitigation options is employed. By closing the information gap on mitigation costs, society and policymakers will be far better prepared to identify and implement optimal policies for managing the risks associated with climate change. Establishment of practical experience in providing

  14. Selecting iodine-enriched vegetables and the residual effect of iodate application to soil.

    Science.gov (United States)

    Dai, Jiu-Lan; Zhu, Yong-Guan; Zhang, Min; Huang, Yi-Zhong

    2004-12-01

    A greenhouse pot experiment was conducted to select vegetables for iodine uptake. The residual effect of iodate fertilization on the growth of and iodine uptake by spinach plants were also investigated. Six vegetables, including leafy vegetables (pakchoi [Brassica chinensis L.], spinach [Spinacia oleracea L.]), tuber vegetables (onion [Allium cepa L.]), shoot vegetables (water spinach [Ipomoea aquatica Forsk.], celery [Apium graveolens L.]), and root vegetables (carrot [Daucus carota var. sativa DC.]) were examined. Results showed that the concentrations of iodate in soil had significant effect on the biomass of edible parts of pakchoi and spinach (pIodine concentrations in edible parts of vegetables and the transfer factors (TFedible parts) of soil-to-edible parts of vegetables significantly increased with increasing iodine concentrations in soil (piodine concentrations in edible parts and TFedible parts of spinach were much higher than those of other vegetables at any treatment. Both transfer coefficients for edible parts (TCedible parts) and for aerial parts (TCaerial parts) of vegetables changed differently with increasing iodine concentrations in the soil, and TCedible parts and TCaerial parts of spinach were higher than those of other vegetables. Therefore, spinach was considered as an efficient vegetable for iodine biofortification. Further experiment showed that there is considerable residual effect of soil fertilization with iodate.

  15. Increased annoyance from illuminance of greenhouses in areas not familiar with greenhouses

    NARCIS (Netherlands)

    Oel, C. van; Janssen, E.G.O.N.; Alferdinck, J.W.A.M.; Ruigrok, J.

    2007-01-01

    Many greenhouses use artificial light to grow plants, causing visible sky glow. Initially, low density growth lights were used. With the introduction of high density grow lights, the sky glow luminance of greenhouses has considerably risen. In the urbanized western parts of Holland, old warehouses a

  16. 智能温室大棚控制系统%Intelligent Control System for Greenhouse

    Institute of Scientific and Technical Information of China (English)

    孟凡奥; 何豪; 刘晓芸; 张凌飞

    2014-01-01

    In order to improve the production of vegetables in the greenhouse,to grasp temperature,soil humidity,concentration of carbon dioxide and intensity of il umination in greenhouse promptly and real-time monitoring.This paper describes the structure,function and principle of a intel igent greenhouse control system based on microcontrol er.by setting the best environment parameters for different periods of crop growth to achieve greenhouse science,intel igent,efifcient management.%为提高温室大棚内蔬菜的产量,及时掌握棚内温度、土壤湿度、CO2浓度和光照强度等参数,并进行实时测控,本文介绍一种基于单片机的智能温室大棚控制系统的结构、功能和原理,通过设定不同时期作物生长所需要的最佳环境参数,从而实现温室大棚科学、智能化、高效率的管理。

  17. Preliminary study on the variation of radon-222 inside greenhouse of Shouguang county, China.

    Science.gov (United States)

    Li, Xiaohong; Xu, Xianqin; Li, Wanwei; Wang, Fei; Hai, Chunxu

    2016-03-01

    Studies on radon have become the focus of indoor radiation. In this study, we chose greenhouse to be the study field, the research aims to: (1) explore the diurnal variation of radon concentration inside greenhouse in Shouguang county, China; (2) pre-analyze the relationship between radon concentration, temperature and relative humidity, and shed light on the radon behavior characteristic inside greenhouse; (3) verify the feasibility of calculating radon radiation dose by using short-period detected radon concentrations in typical months in Shouguang county. The following conclusions were drawn. Firstly, the average radon levels in typical months in Shouguang county are all much higher than that in ordinary dwellings in China, diurnal and seasonal variations in radon levels are observed inside greenhouse. Secondly, temperature and relative humidity may play a role indirectly through affecting soil moisture and other factors. The mechanism need to be further studied. Thirdly, radon concentrations detected in typical months are still useful in preliminary estimation of radon radiation dose for vegetable-plant farmers in Shouguang county.

  18. Technology Drives Vegetable Industry

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    @@ Arobot for vegetable planting is able to examine growing conditions, detect disease of the vegetables and pick up the ripe ones through identifying the color; a tomato tree is able to produce up to 3,000kgs of tomatoes; sweet potatoes are growing in the air; fish and vegeta-bles are living together harmoniously...Viewing these, you may doubt that you were in a fancy world.Actually, you are here at the 12th China (Shouguang) International Vegetable Sci-tech Fair.

  19. Economic Sustainability of Italian Greenhouse Cherry Tomato

    Directory of Open Access Journals (Sweden)

    Riccardo Testa

    2014-11-01

    Full Text Available Greenhouse tomato cultivation plays an important role in Sicily, being the primary production area in Italy, due to its favorable pedo-climatic conditions that permit extra-seasonal productions. In Sicily, more than half of greenhouse tomato production is derived from the Province of Ragusa on the southeastern coast, where especially cherry tomato typologies are cultivated. Over the last decade, the Ragusa Province has registered a decrease both in terms of greenhouse tomato area and harvested production due to several structural problems that would require restructuring of the tomato supply chain. Thus, since recognition of real costs and profitability of tomato growing is a vital issue, both from the perspective of the farm, as well as from that of the entrepreneur, the aim of this paper was to analyze the economic sustainability of Sicilian greenhouse cherry tomato cultivated in the Ragusa Province. In particular, an economic analysis on 30 representative farms was conducted in order to estimate production costs and profits of greenhouse cherry tomato. According to our results, the lack of commercial organization, which characterizes the small farms we surveyed, determines low contractual power for farmers and, consequently, low profitability.

  20. Efeito da rega com injecção de ar na humidade do solo, dis­ponibilidade de azoto nítrico, condutividade eléctrica e pro­dutividade da alface cultivada em estufa plástica Effects of irrigation with injection of air in soil moisture, nitrate avail­ability, electrical conductivity and lettuce productivity grown in plastic greenhouse

    Directory of Open Access Journals (Sweden)

    C.R. Pivetta

    2010-01-01

    Full Text Available Este trabalho teve como objectivo veri­ficar se a injecção de ar junto a água de rega gota-a-gota enterrada, afecta a humi­dade do solo, a disponibilidade de azoto nítrico, a condutividade eléctrica e o cres­cimento e produtividade da alface. Para tal realizou-se um ensaio com a alface variedade “Mention” cultivada em estufa plástica e localizada na Herdade Experi­mental da Mitra-ICAAM, da Universida­de de Évora -Portugal. Utilizou-se o deli­neamento experimental blocos ao acaso com quatro repetições, com os tratamen­tos: rega com injecção de ar (CAR, e rega sem injecção de ar (SAR. O ar foi introdu­zido na água de rega por meio de um injector “Mazzei”. O teor de humidade na camada superficial (0-0,05 m foi seme­lhante para os dois tratamentos, alcançan­do valores em torno de zero. Em termos de concentração de azoto nítrico (NO 3- os valores observados na camada 0,10­0,20 m, aos 35 e 47 dias após a transplan­tação, foram mais elevados no tratamento CAR. Aos 47 dias após a transplantação, os níveis médios de NO3-foram de 95,33 e 67,94 ppm nos tratamentos CAR e SAR, respectivamente. A densidade radical no tratamento CAR na camada de 0-0,10 m do solo foi 34 % superior em relação ao SAR. A produção comercial não foi afectada pelo tratamento. A falta de resposta da cultura ao acréscimo de azoto nítrico e da densidade radical pode estar relacionada com o curto ciclo da cultura e/ou com o elevado teor de azoto presente no solo, ou ainda com a profundidade que os goteja­dores foram instalados e não com a fun­cionalidade do injector de ar.The objective of the present study was to evaluate the effect of the air injection through subsurface drip irrigation (oxyga­tion in soil moisture, availability of nitro­gen oxide, and electrical conductivity, plant growth and yield of lettuce, variety "Men­tion", cultivated in plastic greenhouse. The experiment was carried out at the Mitra-ICAM, an Experimental

  1. Neural plasticity lessons from disorders of consciousness

    Directory of Open Access Journals (Sweden)

    Athena eDemertzi

    2011-02-01

    Full Text Available Communication and intentional behavior are supported by the brain’s integrity at a structural and a functional level. When widespread loss of cerebral connectivity is brought about as a result of a severe brain injury, in many cases patients are not capable of conscious interactive behavior and are said to suffer from disorders of consciousness (e.g., coma, vegetative state /unresponsive wakefulness syndrome, minimally conscious states. This lesion paradigm has offered not only clinical insights, as how to improve diagnosis, prognosis and treatment, but also put forward scientific opportunities to study the brain’s plastic abilities. We here review interventional and observational studies performed in severely brain-injured patients with regards to recovery of consciousness. The study of the recovered conscious brain (spontaneous and/or after surgical or pharmacologic interventions, suggests a link between some specific brain areas and the capacity of the brain to sustain conscious experience, challenging at the same time the notion of fixed temporal boundaries in rehabilitative processes. Altered functional connectivity, cerebral structural reorganization as well as behavioral amelioration after invasive treatments will be discussed as the main indices for plasticity in these challenging patients. The study of patients with chronic disorders of consciousness may, thus, provide further insights not only at a clinical level (i.e., medical management and rehabilitation but also from a scientific-theoretical perspective (i.e., the brain’s plastic abilities and the pursuit of the neural correlate of consciousness.

  2. Neural plasticity lessons from disorders of consciousness.

    Science.gov (United States)

    Demertzi, Athena; Schnakers, Caroline; Soddu, Andrea; Bruno, Marie-Aurélie; Gosseries, Olivia; Vanhaudenhuyse, Audrey; Laureys, Steven

    2010-01-01

    Communication and intentional behavior are supported by the brain's integrity at a structural and a functional level. When widespread loss of cerebral connectivity is brought about as a result of a severe brain injury, in many cases patients are not capable of conscious interactive behavior and are said to suffer from disorders of consciousness (e.g., coma, vegetative state/unresponsive wakefulness syndrome, minimally conscious states). This lesion paradigm has offered not only clinical insights, as how to improve diagnosis, prognosis, and treatment, but also put forward scientific opportunities to study the brain's plastic abilities. We here review interventional and observational studies performed in severely brain-injured patients with regards to recovery of consciousness. The study of the recovered conscious brain (spontaneous and/or after surgical or pharmacologic interventions), suggests a link between some specific brain areas and the capacity of the brain to sustain conscious experience, challenging at the same time the notion of fixed temporal boundaries in rehabilitative processes. Altered functional connectivity, cerebral structural reorganization as well as behavioral amelioration after invasive treatments will be discussed as the main indices for plasticity in these challenging patients. The study of patients with chronic disorders of consciousness may, thus, provide further insights not only at a clinical level (i.e., medical management and rehabilitation) but also from a scientific-theoretical perspective (i.e., the brain's plastic abilities and the pursuit of the neural correlate of consciousness).

  3. Review of Heterogeneous Catalysts for Catalytically Upgrading Vegetable Oils into Hydrocarbon Biofuels

    Directory of Open Access Journals (Sweden)

    Xianhui Zhao

    2017-03-01

    Full Text Available To address the issues of greenhouse gas emissions associated with fossil fuels, vegetable oilseeds, especially non-food oilseeds, are used as an alternative fuel resource. Vegetable oil derived from these oilseeds can be upgraded into hydrocarbon biofuel. Catalytic cracking and hydroprocessing are two of the most promising pathways for converting vegetable oil to hydrocarbon biofuel. Heterogeneous catalysts play a critical role in those processes. The present review summarizes current progresses and remaining challenges of vegetable oil upgrading to biofuel. The catalyst properties, applications, deactivation, and regeneration are reviewed. A comparison of catalysts used in vegetable oil and bio-oil upgrading is also carried out. Some suggestions for heterogeneous catalysts applied in vegetable oil upgrading to improve the yield and quality of hydrocarbon biofuel are provided for further research in the future.

  4. Vermicomposting of Vegetable Wastes Using Cow Dung

    Directory of Open Access Journals (Sweden)

    K. Muthukumaravel

    2008-01-01

    Full Text Available Municipal solid wastes are mainly from domestic and commercial areas containing recyclable toxic substances, compostable organic matter and others. With rapid increase in population, the generation of municipal solid wastes has increased several folds during last few years. Disposal of solid wastes can be done by methods like land filling, incineration, recycling, conversion into biogas, disposal into sea and composting. Vermicomposting is one of the recycling technologies which will improve the quality of the products. The present study aims to find out the possibility of utilization of vegetable wastes for vermiculture. Earthworm Megascolex mauritii cultured in plastic trays (45 x 30 x 30 cm containing soil alone (control (T1, soil + cow dung (T2, soil + vegetable waste (T3 and soil + vegetable waste + cow dung (T4 for 60 days. Nutrient values were determined from the compost and compared with that of the control. From these results, it was found that NPK values were maximum in compost obtained from vegetable waste with the use of cow dung.

  5. New renewable source of energy from municipal solid waste plastics

    Energy Technology Data Exchange (ETDEWEB)

    Sarker, Moinuddin; Zaman, Ashiquz; Mamunor Rashid, Mohammad

    2010-09-15

    Renewable energy plays an important role in the supply of energy. When energy sources are used, the demand for fossil fuels is reduced. Emissions from the evaporation and combustion of these traditional fossil fuels contributing to a range of environmental and health problems, causing poor air quality, and emitting greenhouse gases that contribute to global warming. Alternative fuel created from domestic sources has been proposed as a solution to these problems and many alternative fuels are being developed based on solar, wind and biomass. Natural State Research has developed different alternative hydrocarbon fuel produced from abundant waste plastic materials.

  6. Voluntary reporting of greenhouse gases 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-05-01

    The Voluntary Reporting of Greenhouse Gases Program, required by Section 1605(b) of the Energy Policy Act of 1992, records the results of voluntary measures to reduce, avoid, or sequester greenhouse gas emissions. In 1998, 156 US companies and other organizations reported to the Energy information Administration that, during 1997, they had achieved greenhouse gas emission reductions and carbon sequestration equivalent to 166 million tons of carbon dioxide, or about 2.5% of total US emissions for the year. For the 1,229 emission reduction projects reported, reductions usually were measured by comparing an estimate of actual emissions with an estimate of what emissions would have been had the project not been implemented.

  7. FETC Programs for Reducing Greenhouse Gas Emissions

    Energy Technology Data Exchange (ETDEWEB)

    Ruether, J.A.

    1998-02-01

    Mark Twain once quipped that everyone talks about the weather but no one does anything about it. With interest in global climate change on the rise, researchers in the fossil-energy sector are feeling the heat to provide new technology to permit continued use of fossil fuels but with reduced emissions of so-called `greenhouse gases.` Three important greenhouse gases, carbon dioxide, methane, and nitrous oxide, are released to the atmosphere in the course of recovering and combusting fossil fuels. Their importance for trapping radiation, called forcing, is in the order given. In this report, we briefly review how greenhouse gases cause forcing and why this has a warming effect on the Earth`s atmosphere. Then we discuss programs underway at FETC that are aimed at reducing emissions of methane and carbon dioxide.

  8. The Greenhouse Effect and Climate Feedbacks

    Science.gov (United States)

    Covey, C.; Haberle, R. M.; McKay, C. P.; Titov, D. V.

    This chapter reviews the theory of the greenhouse effect and climate feedback. It also compares the theory with observations, using examples taken from all four known terrestrial worlds with substantial atmospheres: Venus, Earth, Mars, and Titan. The greenhouse effect traps infrared radiation in the atmosphere, thereby increasing surface temperature. It is one of many factors that affect a world's climate. (Others include solar luminosity and the atmospheric scattering and absorption of solar radiation.) A change in these factors — defined as climate forcing — may change the climate in a way that brings other processes — defined as feedbacks — into play. For example, when Earth's atmospheric carbon dioxide increases, warming the surface, the water vapor content of the atmosphere increases. This is a positive feedback on global warming because water vapor is itself a potent greenhouse gas. Many positive and negative feedback processes are significant in determining Earth's climate, and probably the climates of our terrestrial neighbors.

  9. Continuous greenhouse gas measurements from ice cores

    DEFF Research Database (Denmark)

    Stowasser, Christopher

    -consuming and labor-intensive. This PhD thesis presents the development of a new method for measurements of greenhouse gas mixing ratios from ice cores based on a melting device of a continuous flow analysis (CFA) system. The coupling to a CFA melting device enables time-efficient measurements of high resolution......Ice cores offer the unique possibility to study the history of past atmospheric greenhouse gases over the last 800,000 years, since past atmospheric air is trapped in bubbles in the ice. Since the 1950s, paleo-scientists have developed a variety of techniques to extract the trapped air from...... individual ice core samples, and to measure the mixing ratio of greenhouse gases such as carbon dioxide, methane and nitrous oxide in the extracted air. The discrete measurements have become highly accurate and reproducible, but require relatively large amounts of ice per measured species and are both time...

  10. Balkan Vegetation Database

    NARCIS (Netherlands)

    Vassilev, Kiril; Pedashenko, Hristo; Alexandrova, Alexandra; Tashev, Alexandar; Ganeva, Anna; Gavrilova, Anna; Gradevska, Asya; Assenov, Assen; Vitkova, Antonina; Grigorov, Borislav; Gussev, Chavdar; Filipova, Eva; Aneva, Ina; Knollová, Ilona; Nikolov, Ivaylo; Georgiev, Georgi; Gogushev, Georgi; Tinchev, Georgi; Pachedjieva, Kalina; Koev, Koycho; Lyubenova, Mariyana; Dimitrov, Marius; Apostolova-Stoyanova, Nadezhda; Velev, Nikolay; Zhelev, Petar; Glogov, Plamen; Natcheva, Rayna; Tzonev, Rossen; Boch, Steffen; Hennekens, Stephan M.; Georgiev, Stoyan; Stoyanov, Stoyan; Karakiev, Todor; Kalníková, Veronika; Shivarov, Veselin; Russakova, Veska; Vulchev, Vladimir

    2016-01-01

    The Balkan Vegetation Database (BVD; GIVD ID: EU-00-019; http://www.givd.info/ID/EU-00- 019) is a regional database that consists of phytosociological relevés from different vegetation types from six countries on the Balkan Peninsula (Albania, Bosnia and Herzegovina, Bulgaria, Kosovo, Montenegro

  11. Balkan Vegetation Database

    NARCIS (Netherlands)

    Vassilev, Kiril; Pedashenko, Hristo; Alexandrova, Alexandra; Tashev, Alexandar; Ganeva, Anna; Gavrilova, Anna; Gradevska, Asya; Assenov, Assen; Vitkova, Antonina; Grigorov, Borislav; Gussev, Chavdar; Filipova, Eva; Aneva, Ina; Knollová, Ilona; Nikolov, Ivaylo; Georgiev, Georgi; Gogushev, Georgi; Tinchev, Georgi; Pachedjieva, Kalina; Koev, Koycho; Lyubenova, Mariyana; Dimitrov, Marius; Apostolova-Stoyanova, Nadezhda; Velev, Nikolay; Zhelev, Petar; Glogov, Plamen; Natcheva, Rayna; Tzonev, Rossen; Boch, Steffen; Hennekens, Stephan M.; Georgiev, Stoyan; Stoyanov, Stoyan; Karakiev, Todor; Kalníková, Veronika; Shivarov, Veselin; Russakova, Veska; Vulchev, Vladimir

    2016-01-01

    The Balkan Vegetation Database (BVD; GIVD ID: EU-00-019; http://www.givd.info/ID/EU-00- 019) is a regional database that consists of phytosociological relevés from different vegetation types from six countries on the Balkan Peninsula (Albania, Bosnia and Herzegovina, Bulgaria, Kosovo, Montenegro

  12. Soil and vegetation surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Antonio, E.J.

    1995-06-01

    Soil sampling and analysis evaluates long-term contamination trends and monitors environmental radionuclide inventories. This section of the 1994 Hanford Site Environmental Report summarizes the soil and vegetation surveillance programs which were conducted during 1994. Vegetation surveillance is conducted offsite to monitor atmospheric deposition of radioactive materials in areas not under cultivation and onsite at locations adjacent to potential sources of radioactivity.

  13. SABIC Innovative Plastics: Be the World Best Plastic Resin Manufacturer

    Institute of Scientific and Technical Information of China (English)

    Jenny Du

    2007-01-01

    @@ "SABIC Innovative Plastics is a global supplier of plastic resins, manufacturing and compounding polycarbonate, ABS, SAN, ASA, PPE, PC/ABS, PBT and PEI resins, as well as the LNP* line of high performance specialty compounds," said Hiroshi Yoshida, the Global Market Director for Electronics of SABIC Innovative Plastics based in Tokyo at the press conference held by SABIC Innovative Plastics, November 8th 2007, Shanghai.

  14. Effect of Root Layer Regulations on Soil Nitrate of the Rotation System of Sweet Corn-Cucumber in Greenhouse Vegetable Production System%根层调控措施对甜玉米-黄瓜设施蔬菜轮作体系土壤硝态氮的影响

    Institute of Scientific and Technical Information of China (English)

    郝晓然; 彭亚静; 张丽娟; 王琳; 巨晓棠; 吉艳芝; 任翠莲

    2015-01-01

    , and conditioning treatment was significantly higher than that of traditional planting.[Conclusion]In the greenhouse soil with high nitrate accumulation, along with the increasing length of planting, adding soil conditioner to soil and appropriate straw returning to field, the subtraction of NO3--N in 100-200 cm of the crop root zone was more than traditional planting. Planting catch crops significantly decreased the effects of soil NO3--N in soil of the succession cucumber. Soil conditioners and straw returning to field can significantly improve the ability of sweet corn to decrease soil NO3--N, slow soil NO3--N leaching, and improve economic returns.

  15. Dynamic assessment of air temperature for tomato (Lycopersicon esculentum mill) cultivation in a naturally ventilated net-screen greenhouse under tropical lowlands climate

    NARCIS (Netherlands)

    Shamshiri, R.; Beveren, van P.; Che Man, H.; Zakaria, A.J.

    2017-01-01

    Net-screen covered greenhouses operating on natural ventilation are used as a sustainable approach for closed-field cultivation of fruits and vegetables and to eliminate insect passage and the subsequent production damage. The objective of this work was to develop a real-time assessment framework fo

  16. Effect of the Evaporative Cooling on the Human Thermal Comfort and Heat Stress in a Greenhouse under Arid Conditions

    Directory of Open Access Journals (Sweden)

    A. M. Abdel-Ghany

    2013-01-01

    Full Text Available Thermal sensation and heat stress were evaluated in a plastic greenhouse, with and without evaporative cooling, under arid climatic conditions in Riyadh, Saudi Arabia. Suitable thermal comfort and heat stress scales were selected for the evaluation. Experiments were conducted in hot sunny days to measure the required parameters (i.e., the dry and wet bulb temperatures, globe temperature, natural wet bulb temperature, and solar radiation flux in the greenhouse. The results showed that in the uncooled greenhouse, workers are exposed to strong heat stress and would feel very hot most of the day time; they are safe from heat stress risk and would feel comfortable during night. An efficient evaporative cooling is necessary during the day to reduce heat stress and to improve the comfort conditions and is not necessary at night. In the cooled greenhouse, workers can do any activity: except at around noon they should follow a proposed working schedule, in which the different types of work were scheduled along the daytimes based on the heat stress value. To avoid heat stress and to provide comfort conditions in the greenhouses, the optimum ranges of relative humidity and air temperature are 48–55% and 24–28°C, respectively.

  17. Preserving in Plastic.

    Science.gov (United States)

    Wahla, James

    1985-01-01

    Outlines steps for casting insects in permanent molds prepared from commercially available liquid plastic. Also describes dry mountings in glass, acrylic, and petri dishes. The rationale for specimen use, hints for producing quality results, purchasing information, and safety precautions are considered. (DH)

  18. Informative document waste plastics

    NARCIS (Netherlands)

    Nagelhout D; Sein AA; Duvoort GL

    1989-01-01

    This "Informative document waste plastics" forms part of a series of "informative documents waste materials". These documents are conducted by RIVM on the indstruction of the Directorate General for the Environment, Waste Materials Directorate, in behalf of the program of acti

  19. Discrete dislocation plasticity

    NARCIS (Netherlands)

    van der Giessen, E.; Finel, A; Maziere, D; Veron, M

    2003-01-01

    Conventional continuum mechanics models of inelastic deformation processes axe size scale independent. In contrast, there is considerable experimental evidence that plastic flow in crystalline materials is size dependent over length scales of the order of tens of microns and smaller. At present ther

  20. Progress in neural plasticity

    Institute of Scientific and Technical Information of China (English)

    POO; Mu-Ming

    2010-01-01

    One of the properties of the nervous system is the use-dependent plasticity of neural circuits.The structure and function of neural circuits are susceptible to changes induced by prior neuronal activity,as reflected by short-and long-term modifications of synaptic efficacy and neuronal excitability.Regarded as the most attractive cellular mechanism underlying higher cognitive functions such as learning and memory,activity-dependent synaptic plasticity has been in the spotlight of modern neuroscience since 1973 when activity-induced long-term potentiation(LTP) of hippocampal synapses was first discovered.Over the last 10 years,Chinese neuroscientists have made notable contributions to the study of the cellular and molecular mechanisms of synaptic plasticity,as well as of the plasticity beyond synapses,including activity-dependent changes in intrinsic neuronal excitability,dendritic integration functions,neuron-glia signaling,and neural network activity.This work highlight some of these significant findings.

  1. New plastic recycling technology

    Science.gov (United States)

    Greater than 60% of the total plastic content of municipal solid waste is comprised of polyolefins (high-density, low-density, and linear polyethylene and polypropylene. Polyethylene (PE) is the largest-volume component but presents a challenge due to the absence of low-energy de...

  2. Greenhouse of the future. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Cavin, B. III

    1998-07-03

    This greenhouse of the future is located at the Center for Regenerative Studies (CRS) at Cal Poly Pomona. The building design was driven by desired environmental conditions. The primary objective was to keep the interior space warm during winter for the breeding of fish and other greenhouse activities, especially in the winter. To do this, a highly insulating envelope was needed. Straw bales provide excellent insulation with an R-value of approximately 50 and also help solve the environmental problems associated with this agricultural waste product. A summary of the construction progress, construction costs and operating costs are included.

  3. Greenhouse gases and the metallurgical process industry

    Energy Technology Data Exchange (ETDEWEB)

    Lupis, C.H.P.

    1999-10-01

    The present lecture offers a brief review of the greenhouse effect, the sources of greenhouse gases, the potential effect of these gases on global warming, the response of the international community, and the probable cost of national compliance. The specific emissions of the metallurgical process industry, particularly those of the steel and aluminum sectors, are then examined. The potential applications of life-cycle assessments and of an input-output model in programs of emissions' abatement are investigated, and, finally, a few remarks on some implications for education are presented.

  4. Solar greenhouse assisted biogas plant in hilly region - A field study

    Energy Technology Data Exchange (ETDEWEB)

    Vinoth Kumar, K.; Kasturi Bai, R. [Department of Bio-Energy, School of Energy, Environment and Natural Resources, Madurai Kamaraj University, Madurai 625 021, Tamil Nadu (India)

    2008-10-15

    The present study was undertaken with the objective of evaluating plastic as an alternative material for biogas plant on a par with conventional brick material. The field study was carried out for one year (October, 2005-September, 2006) in a small hamlet at Nilgiris incorporating solar energy to study its influence on biogas production. During summer (April-June) the temperature reaches to the maximum of 21-25 C and the minimum of 10-12 C. During winter (October-December), the temperature available is maximum of 16-21 C and minimum of 2 C. The solar insolation in the study area ranges from 250 to 600 W/m{sup 2}. This study involves the control conventional Deenabandhu model (Indian standard model prevailing in most part of India made of masonry structure only) and the experimental plastic tank with greenhouse canopy of similar capacity. Our previous work [Vinoth Kumar, K., Kasturi Bai, R., 2005. Plastic biodigesters - a systematic study. Energy for Sustainable Development 9 (4), 40-49] on lab scale digester made from plastic material was compared over other materials and the results gave us much confidence to carry out further study on pilot scale. In continuation, a semi-continuous study was conducted for one year with the retention time of 55 days. The gas generated from the biogas plants was utilized for cooking (burner) and lighting (lamp) purposes. The yearly average slurry temperatures recorded during the study period was 26.3 and 22.4 C in experimental and control biogas plants against ambient temperature of 17.0 C. The yearly average greenhouse chamber temperature recorded was 29.1 C in the experimental biogas plant. The yearly average gas yield from the experimental and control biogas plants were 39.1 and 34.6 l kg{sup -1}day{sup -1} respectively. Gas productions in the winter season registered lower than other months. It can be concluded that the solar greenhouse assisted plastic biogas plant can be efficiently adopted with minor modifications in hilly

  5. Effect of metal stress on the thermal infrared emission of soybeans: A greenhouse experiment - Possible utility in remote sensing

    Science.gov (United States)

    Suresh, R.; Schwaller, M. R.; Foy, C. D.; Weidner, J. R.; Schnetzler, C. S.

    1989-01-01

    Manganese-sensitive forest and manganese-tolerant lee soybean cultivars were subjected to differential manganese stress in loring soil in a greenhouse experiment. Leaf temperature measurements were made using thermistors for forest and lee. Manganese-stressed plants had higher leaf temperatures than control plants in both forest and lee. Results of this experiment have potential applications in metal stress detection using remote sensing thermal infrared data over large areas of vegetation. This technique can be useful in reconnaissance mineral exploration in densely-vegetated regions where conventional ground-based methods are of little help.

  6. Bio-based and biodegradable plastics for use in crop production.

    Science.gov (United States)

    Riggi, Ezio; Santagata, Gabriella; Malinconico, Mario

    2011-01-01

    The production and management of crops uses plastics for many applications (e.g., low tunnels, high tunnels, greenhouses, mulching, silage bags, hay bales, pheromone traps, coatings of fertilizers or pesticides or hormones or seeds, and nursery pots and containers for growing transplants). All these applications have led some authors to adopt the term "plasticulture" when discussing the use of plastic materials in agriculture and related industries. Unfortunately, the sustainability of this use of plastics is low, and renewability and degradability have become key words in the debate over sustainable production and utilization of plastic. Recently, researchers and the plastics industry have made strong efforts (i) to identify new biopolymers and natural additives from renewable sources that can be used in plastics production and (ii) to enhance the degradability (biological or physical) of the new ecologically sustainable materials. In the present review, we describe the main research results, current applications, patents that have been applied for in the last two decades, and future perspectives on sustainable use of plastics to support crop production. The article presents some promising patents on bio-based and biodegradable plastics for use in crop production.

  7. Modeling the infrastructure dynamics of China -- Water, agriculture, energy, and greenhouse gases

    Energy Technology Data Exchange (ETDEWEB)

    Conrad, S.H.; Drennen, T.E.; Engi, D.; Harris, D.L.; Jeppesen, D.M.; Thomas, R.P.

    1998-08-01

    A comprehensive critical infrastructure analysis of the People`s Republic of China was performed to address questions about China`s ability to meet its long-term grain requirements and energy needs and to estimate greenhouse gas emissions in China likely to result from increased agricultural production and energy use. Four dynamic computer simulation models of China`s infrastructures--water, agriculture, energy and greenhouse gas--were developed to simulate, respectively, the hydrologic budgetary processes, grain production and consumption, energy demand, and greenhouse gas emissions in China through 2025. The four models were integrated into a state-of-the-art comprehensive critical infrastructure model for all of China. This integrated model simulates diverse flows of commodities, such as water and greenhouse gas, between the separate models to capture the overall dynamics of the integrated system. The model was used to generate projections of China`s available water resources and expected water use for 10 river drainage regions representing 100% of China`s mean annual runoff and comprising 37 major river basins. These projections were used to develop estimates of the water surpluses and/or deficits in the three end-use sectors--urban, industrial, and agricultural--through the year 2025. Projections of the all-China demand for the three major grains (corn, wheat, and rice), meat, and other (other grains and fruits and vegetables) were also generated. Each geographic region`s share of the all-China grain demand (allocated on the basis of each region`s share of historic grain production) was calculated in order to assess the land and water resources in each region required to meet that demand. Growth in energy use in six historically significant sectors and growth in greenhouse gas loading were projected for all of China.

  8. A QSPR for the plasticization efficiency of polyvinylchloride plasticizers.

    Science.gov (United States)

    Chandola, Mridula; Marathe, Sujata

    2008-01-01

    A simple quantitative structure property relationship (QSPR) for correlating the plasticization efficiency of 25 polyvinylchloride (PVC) plasticizers was obtained using molecular modeling. The plasticizers studied were-aromatic esters (phthalate, terephthalate, benzoate, trimellitate), aliphatic esters (adipate, sebacate, azelate), citrates and a phosphate. The low temperature flex point, Tf, of plasticized polyvinylchloride resins was considered as an indicator of plasticization efficiency. Initially, we attempted to predict plasticization efficiency of PVC plasticizers from physical and structural descriptors derived from the plasticizer molecule alone. However, the correlation of these descriptors with Tf was not very good with R=0.78 and r2=0.613. This implied that the selected descriptors were unable to predict all the interactions between PVC and plasticizer. Hence, to account for these interactions, a model containing two polyvinylchloride (PVC) chain segments along with a plasticizer molecule in a simulation box was constructed, using molecular mechanics. A good QSPR equation correlating physical and structural descriptors derived from the model to Tf of the plasticized resins was obtained with R=0.954 and r2=0.909.

  9. Within-plant distribution of Aulacorthum solani (Hemiptera: Aphididae), on various greenhouse plants with implications for control.

    Science.gov (United States)

    Jandricic, S E; Mattson, N S; Wraight, S P; Sanderson, J P

    2014-04-01

    Foxglove aphid, Aulacorthum solani (Kaltenbach) (Hemiptera: Aphididae), has recently undergone a status change from an occasional pest to a serious pest in greenhouses of North America and the United Kingdom. Little nonanecdotal information exists on the ecology of this insect in greenhouse crops. To help improve integrated pest management decisions for A. solani, the within-plant distribution of this pest was explored on a variety of common greenhouse plants in both the vegetative and flowering stage. This aphid generally was found on lower leaves of vegetative plants, but was found higher in the canopy on reproductive plants (on flowers, flower buds, or upper leaves). Aphid numbers were not consistently positively correlated with total leaf surface areas within plant strata across plant species. Thus, the observed differences in preferred feeding sites on vegetative versus flowering plants are possibly a response to differences in nutritional quality of the various host-plant tissues. Despite being anecdotally described as a "stem-feeding aphid," A. solani was rarely found feeding on stems at the population densities established in our tests, with the exception of racemes of scarlet sage (Salvia splendans). Although some previous reports suggested that A. solani prefers to feed on new growth of plants, our results indicate that mature leaves are preferred over growing tips and young leaves. The implications of the within-plant feeding preferences of A. solani populations with respect to both biological and chemical control are discussed.

  10. Greenhouse Gas Emission Curb Favors China's Economy

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ Living affluently while breathing in polluted air is not a desirable lifestyle. The longwaited Kyoto Protocol went into force on February 16, winning big applause around the globe. China, as a developing country, doesn't have to follow Kyoto Protocol and reduce its greenhouse gas emissions, but China, as part of the global village, will not escape similar obligations in the future.

  11. Global comparison of three greenhouse climate models

    NARCIS (Netherlands)

    Bavel, van C.H.M.; Takakura, T.; Bot, G.P.A.

    1985-01-01

    Three dynamic simulation models for calculating the greenhouse climate and its energy requirements for both heating and cooling were compared by making detailed computations for each of seven sets of data. The data sets ranged from a cold winter day, requiring heating, to a hot summer day, requiring

  12. Earthworms and the soil greenhouse gas balance

    NARCIS (Netherlands)

    Lubbers, I.M.

    2014-01-01

      Earthworms play an essential part in determining the greenhouse gas (GHG) balance of soils worldwide. Their activity affects both biotic and abiotic soil properties, which in turn influence soil GHG emissions, carbon (C) sequestration and plant growth. Yet, the balance of earthworms stimulat

  13. Modern, sustainable, protected greenhouse cultivation in Algeria

    NARCIS (Netherlands)

    Os, van E.A.; Speetjens, S.L.; Ruijs, M.N.A.; Bruins, M.A.; Sapounas, A.

    2012-01-01

    The goal of the project was to analyse the structure and technology level of protected cultivation in Algeria, which were followed by recommendations for improvements (technical, cultivation and economic aspects) of existing and newly built greenhouses. Further, in discussion with Dutch and Algerian

  14. Greenhouse gas emissions trading in the EU

    NARCIS (Netherlands)

    Peeters, Marjan; Farber, Daniel A.; Peeters, Marjan

    2016-01-01

    The major regulatory experiment with greenhouse gas emissions trading in the EU enables legal scholars to learn lessons regarding its design options and implementation problems. Some fundamental concerns are: (1) the issue of how to develop a fair allocation method, also in view of carbon leakage; (

  15. The EU Greenhouse Gas Emissions Trading Scheme

    NARCIS (Netherlands)

    Woerdman, Edwin; Woerdman, Edwin; Roggenkamp, Martha; Holwerda, Marijn

    2015-01-01

    This chapter explains how greenhouse gas emissions trading works, provides the essentials of the Directive on the European Union Emissions Trading Scheme (EU ETS) and summarizes the main implementation problems of the EU ETS. In addition, a law and economics approach is used to discuss the dilemmas

  16. Occupational allergy in Strawberry Greenhouse workers

    NARCIS (Netherlands)

    J.A. Patiwael (Jiska); L.G.J. Vullings; N.W. de Jong (Nicolette); A.W. van Toorenenbergen (Albert); R. Gerth van Wijk (Roy); H. de Groot (Hans)

    2010-01-01

    textabstractBackground: Employees in strawberry greenhouses are highly exposed to several (potential) allergenic agents. However, no occupational allergy in this branch has been described before. First, the presence of work-related allergic symptoms in strawberry workers was explored. Second, we aim

  17. Off-season greenhouse strawberry production

    Science.gov (United States)

    Strawberry production in the mid-South is mostly done in the field with harvest from April to June. There is year-round demand for fruit with the highest prices from November through February. Our research is ongoing to evaluate off-season strawberry production in polyethylene-covered greenhouses....

  18. Greenhouse effect due to chlorofluorocarbons - Climatic implications

    Science.gov (United States)

    Ramanathan, V.

    1975-01-01

    The infrared bands of chlorofluorocarbons and chlorocarbons enhance the atmospheric greenhouse effect. This enhancement may lead to an appreciable increase in the global surface temperature if the atmospheric concentrations of these compounds reach values of the order of 2 parts per billion.

  19. Greenhouse Gas Analysis at the World Bank

    OpenAIRE

    World Bank

    2012-01-01

    This report builds on reviews of available methodologies, tools, and practices for greenhouse gas (GHG) analysis, and summarizes the outcomes of pilot studies. It discusses the issues and challenges associated with GHG analysis for energy, transport and forestry projects such as setting project boundaries and accounting for indirect emissions. To do this it draws on existing United Nations...

  20. Time to pregnancy among female greenhouse workers.

    NARCIS (Netherlands)

    Bretveld, R.W.; Zielhuis, G.A.; Roeleveld, N.

    2006-01-01

    OBJECTIVES: Female greenhouse workers, who constitute a major occupational group exposed to pesticides at childbearing age, were studied to measure the effects of pesticide exposure on time to pregnancy. METHODS: Data were collected through postal questionnaires with detailed questions on time to pr

  1. Broader perspectives for comparing different greenhouse gases.

    Science.gov (United States)

    Manning, Martin; Reisinger, Andy

    2011-05-28

    Over the last 20 years, different greenhouse gases have been compared, in the context of climate change, primarily through the concept of global warming potentials (GWPs). This considers the climate forcing caused by pulse emissions and integrated over a fixed time horizon. Recent studies have shown that uncertainties in GWP values are significantly larger than previously thought and, while past literature in this area has raised alternative means of comparison, there is not yet any clear alternative. We propose that a broader framework for comparing greenhouse gases has become necessary and that this cannot be addressed by using simple fixed exchange rates. From a policy perspective, the framework needs to be clearly aligned with the goal of climate stabilization, and we show that comparisons between gases can be better addressed in this context by the forcing equivalence index (FEI). From a science perspective, a framework for comparing greenhouse gases should also consider the full range of processes that affect atmospheric composition and how these may alter for climate stabilization at different levels. We cover a basis for a broader approach to comparing greenhouse gases by summarizing the uncertainties in GWPs, linking those to uncertainties in the FEIs consistent with stabilization, and then to a framework for addressing uncertainties in the corresponding biogeochemical processes.

  2. Studying the Greenhouse Effect: A Simple Demonstration.

    Science.gov (United States)

    Papageorgiou, G.; Ouzounis, K.

    2000-01-01

    Studies the parameters involved in a presentation of the greenhouse effect and describes a simple demonstration of this effect. Required equipment includes a 100-120 watt lamp, a 250mL beaker, and a thermometer capable of recording 0-750 degrees Celsius together with a small amount of chloroform. (Author/SAH)

  3. Modeling Greenhouse Gas Emissions from Enteric Fermentation

    NARCIS (Netherlands)

    Kebreab, E.; Tedeschi, L.; Dijkstra, J.; Ellis, J.L.; Bannink, A.; France, J.

    2016-01-01

    Livestock directly contribute to greenhouse gas (GHG) emissions mainly through methane (CH4) and nitrous oxide (N2O) emissions. For cost and practicality reasons, quantification of GHG has been through development of various types of mathematical models. This chapter addresses the utility and limita

  4. A greenhouse without pesticides : fact or fantasy ?

    NARCIS (Netherlands)

    Lenteren, van J.C.

    2000-01-01

    Crop protection in European greenhouses became strongly chemically oriented shortly after the Second World War in the 1950s. But an excellent climate for fast reproduction of pests and diseases demanded high spray frequencies and, thus, resulted in quick development of resistance against pesticides.

  5. Earthworms and the soil greenhouse gas balance

    NARCIS (Netherlands)

    Lubbers, I.M.

    2014-01-01

      Earthworms play an essential part in determining the greenhouse gas (GHG) balance of soils worldwide. Their activity affects both biotic and abiotic soil properties, which in turn influence soil GHG emissions, carbon (C) sequestration and plant growth. Yet, the balance of earthworms stimulat

  6. Greenhouse warming and changes in sea level

    NARCIS (Netherlands)

    Oerlemans, J.

    1989-01-01

    It is likely that the anticipated warming due to the effect of increasing concentration of carbon dioxide and other greenhouse gases will lead to a further and faster rise in world mean sea level. There are many processes in the climate system controlling sea level, but the most important factors in

  7. Greenhouse warming and changes in sea level

    NARCIS (Netherlands)

    Oerlemans, J.

    1989-01-01

    It is likely that the anticipated warming due to the effect of increasing concentration of carbon dioxide and other greenhouse gases will lead to a further and faster rise in world mean sea level. There are many processes in the climate system controlling sea level, but the most important

  8. Modern, sustainable, protected greenhouse cultivation in Algeria

    NARCIS (Netherlands)

    Os, van E.A.; Speetjens, S.L.; Ruijs, M.N.A.; Bruins, M.A.; Sapounas, A.

    2012-01-01

    The goal of the project was to analyse the structure and technology level of protected cultivation in Algeria, which were followed by recommendations for improvements (technical, cultivation and economic aspects) of existing and newly built greenhouses. Further, in discussion with Dutch and Algerian

  9. Mitigation of greenhouse gases from agriculture

    DEFF Research Database (Denmark)

    Schils, R.L.M.; Ellis, J. L.; de Klein, C. A. M.

    2013-01-01

    Models are widely used to simulate the emission of greenhouse gases (GHG). They help to identify knowledge gaps, estimate total emissions for inventories, develop mitigation options and policies, raise awareness and encourage adoption. These models vary in scale, scope and methodological approach...

  10. Greenhouse gas abatement strategies for animal husbandry

    NARCIS (Netherlands)

    Monteny, G.J.; Bannink, A.; Chadwick, D.

    2006-01-01

    Agriculture contributes significantly to the anthropogenic emissions of non-CO2 greenhouse gases methane and nitrous oxide. In this paper, a review is presented of the agriculture related sources of methane and nitrous oxide, and of the main strategies for mitigation. The rumen is the most important

  11. Second Greenhouse Gas Information System Workshop

    Science.gov (United States)

    Boland, S. W.; Duren, R. M.; Mitchiner, J.; Rotman, D.; Sheffner, E.; Ebinger, M. H.; Miller, C. E.; Butler, J. H.; Dimotakis, P.; Jonietz, K.

    2009-12-01

    The second Greenhouse Gas Information System (GHGIS) workshop was held May 20-22, 2009 at the Sandia National Laboratories in Albuquerque, New Mexico. The workshop brought together 74 representatives from 28 organizations including U.S. government agencies, national laboratories, and members of the academic community to address issues related to the understanding, operational monitoring, and tracking of greenhouse gas emissions and carbon offsets. The workshop was organized by an interagency collaboration between NASA centers, DOE laboratories, and NOAA. It was motivated by the perceived need for an integrated interagency, community-wide initiative to provide information about greenhouse gas sources and sinks at policy-relevant temporal and spatial scales in order to significantly enhance the ability of national and regional governments, industry, and private citizens to implement and evaluate effective climate change mitigation policies. This talk provides an overview of the second Greenhouse Gas Information System workshop, presents its key findings, and discusses current status and next steps in this interagency collaborative effort.

  12. Greenhouse gas mitigation with scarce land

    DEFF Research Database (Denmark)

    Meyer-Aurich, A; Olesen, Jørgen E; Prochnow, A;

    2013-01-01

    Agricultural lands have been identified to mitigate greenhouse gas (GHG) emissions primarily by production of energy crops and substituting fossil energy resources and through carbon sequestration in soils. Increased fertilizer input resulting in increased yields may reduce the area needed for crop...

  13. Greenhouse Gases from Geothermal Power Production

    OpenAIRE

    Fridriksson, Thráinn; Mateos, Almudena; Audinet, Pierre; Orucu, Yasemin

    2016-01-01

    Geothermal is a renewable source energy that can be used directly for heating or for power production. Geothermal utilization, particularly power production, may result in some greenhouse gas (GHG) emissions. GHG emissions from geothermal power production is generally small in comparison to traditional base load thermal energy power generation facilities. This is mainly due to the fact tha...

  14. Dynamic optimization of artificial lighting in greenhouses.

    NARCIS (Netherlands)

    Heuvelink, E.; Challa, H.

    1989-01-01

    A principle for dynamic optimization of artificial lighting in greenhouses is presented, where the optimization criterion is maximization of the term . To this purpose it is important to consider the break-even point for artificial lighting, which can be defined a

  15. Life cycle assessment of greenhouse gas emissions

    NARCIS (Netherlands)

    Reijnders, L.; Chen, W.Y.; Seiner, J.; Suzuki, T.; Lackner, M.

    2012-01-01

    Life cycle assessments of greenhouse gas emissions have been developed for analyzing products "from cradle to grave": from resource extraction to waste disposal. Life cycle assessment methodology has also been applied to economies, trade between countries, aspects of production and to waste

  16. Life Cycle Assessment of Greenhouse Gas Emissions

    NARCIS (Netherlands)

    Reijnders, L.; Chen, W.Y.; Suzuki, T.; Lackner, M.

    2016-01-01

    Life cycle assessments of greenhouse gas emissions have been developed for analyzing products "from cradle to grave": from resource extraction to waste disposal. Life cycle assessment methodology has also been applied to economies, trade between countries, aspects of production, and waste

  17. The EU Greenhouse Gas Emissions Trading Scheme

    NARCIS (Netherlands)

    Woerdman, Edwin; Woerdman, Edwin; Roggenkamp, Martha; Holwerda, Marijn

    2015-01-01

    This chapter explains how greenhouse gas emissions trading works, provides the essentials of the Directive on the European Union Emissions Trading Scheme (EU ETS) and summarizes the main implementation problems of the EU ETS. In addition, a law and economics approach is used to discuss the dilemmas

  18. Assessment and quantification of plastics waste generation in major 60 cities of India.

    Science.gov (United States)

    Nalini, R; Srinivasulu, B; Shit, Subhas C; Nigam, Suneel Kumar; Akolkar, A B; Dwivedfi, R K

    2013-04-01

    Polymers or plastics materials registered rapid growth in 1970s, 1980s and 1990s at the rate of 2-2.5 times the GDP growth in India. The demand for plastic raw material got more than doubled from 3.3 Million Metric Ton to 6.8 Million Metric Tons in 2010 attributed mainly to rapid urbanization, spread of retail chains, plastics based packaging from grocery to food and vegetable products to cosmetics and consumer items. Plastics packages have its merits over many of conventional materials in the related sector but unless they are collected back effectively after their use to go into recycling process, they become an eyesore in the stream of Municipal Solid Waste (MSW) due to high visibility. As the synthetic and conventional plastics are non-biodegradable in nature, these remain in the dump yards/ landfills for several years, if not collected properly. Due to non- biodegradability, plastics waste remains in the environment for several years, if not collected and disposing plastics wastes at landfills are unsafe since toxic chemicals leach out into the soil and as they contaminate soil and underground water quality. The municipal solid waste also increasing day-by-day due to the inefficient source collection, segregation and transmission of plastics waste for recycling and reusing. In order to find out the realistic plastics waste generation, a study on assessment and quantification of plastics waste has been carried out by CPCB in collaboration with CIPET on selected 60 major cities of India.

  19. Enhanced greenhouse gas emissions from the Arctic with experimental warming

    Science.gov (United States)

    Voigt, Carolina; Lamprecht, Richard E.; Marushchak, Maija E.; Lind, Saara E.; Novakovskiy, Alexander; Aurela, Mika; Martikainen, Pertti J.; Biasi, Christina

    2017-04-01

    Temperatures in the Arctic are projected to increase more rapidly than in lower latitudes. With temperature being a key factor for regulating biogeochemical processes in ecosystems, even a subtle temperature increase might promote the release of greenhouse gases (GHGs) to the atmosphere. Usually, carbon dioxide (CO2) and methane (CH4) are the GHGs dominating the climatic impact of tundra. However, bare, patterned ground features in the Arctic have recently been identified as hot spots for nitrous oxide (N2O). N2O is a potent greenhouse gas, which is almost 300 times more effective in its global warming potential than CO2; but studies on arctic N2O fluxes are rare. In this study we examined the impact of temperature increase on the seasonal GHG balance of all three important GHGs (CO2, CH4 and N2O) from three tundra surface types (vegetated peat soils, unvegetated peat soils, upland mineral soils) in the Russian Arctic (67˚ 03' N 62˚ 55' E), during the course of two growing seasons. We deployed open-top chambers (OTCs), inducing air and soil surface warming, thus mimicking predicted warming scenarios. We combined detailed CO2, CH4 and N2O flux studies with concentration measurements of these gases within the soil profile down to the active layer-permafrost interface, and complemented these GHG measurements with detailed soil nutrient (nitrate and ammonium) and dissolved organic carbon (DOC) measurements in the soil pore water profile. In our study, gentle air warming (˜1.0 ˚ C) increased the seasonal GHG release of all dominant surface types: the GHG budget of vegetated peat and mineral soils, which together cover more than 80 % of the land area in our study region, shifted from a sink to a source of -300 to 144 g CO2-eq m-2 and from -198 to 105 g CO2-eq m-2, respectively. While the positive warming response was governed by CO2, we provide here the first in situ evidence that warming increases arctic N2O emissions: Warming did not only enhance N2O emissions from

  20. Pengaruh Penambahan Kitosan Terhadap Karakteristik Bioplastik Dari Pati Umbi Talas Dengan Menggunakan Plasticizer Gliserol

    OpenAIRE

    Sirait, Toni Pahri

    2015-01-01

    Bioplastic is a plastic which made from renewable biomass sources, such as starch, vegetable oil, and etc. Taro starch (Colocasia esculenta) is a potential raw material for bioplastics by using glycerol as plasticizer and chitosan as a filler. The objective of this research was to investigate the characteristics and gelatinization profile of taro starch, to investigate the effect of adding chitosan and glycerol on mechanical properties such as tensile strength, elongation at br...