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Sample records for processed vegetables aplicacao

  1. Fruit, vegetable, and grain processing wastes

    SciTech Connect

    Andrews, R.M.; Soderquist, M.R.

    1980-06-01

    This is a literature review of fruit, vegetable and grain processing wastes. The factors affecting water usage and methods of conservation were examined. Various processes were investigated which included the pulp recovery from caustic peeled tomato skin, the dewatering of citrus, washing leafy vegetables with recycled process water and the potato processing industry.

  2. Radiation processing of minimally processed vegetables and aromatic plants

    NASA Astrophysics Data System (ADS)

    Trigo, M. J.; Sousa, M. B.; Sapata, M. M.; Ferreira, A.; Curado, T.; Andrada, L.; Botelho, M. L.; Veloso, M. G.

    2009-07-01

    Vegetables are an essential part of people's diet all around the world. Due to cultivate techniques and handling after harvest, these products, may contain high microbial load that can cause food borne outbreaks. The irradiation of minimally processed vegetables is an efficient way to reduce the level of microorganisms and to inhibit parasites, helping a safe global trade. Evaluation of the irradiation's effects was carried out in minimal processed vegetables, as coriander ( Coriandrum sativum L .), mint ( Mentha spicata L.), parsley ( Petroselinum crispum Mill, (A.W. Hill)), lettuce ( Lactuca sativa L.) and watercress ( Nasturium officinale L.). The inactivation level of natural microbiota and the D 10 values of Escherichia coli O157:H7 and Listeria innocua in these products were determined. The physical-chemical and sensorial characteristics before and after irradiation at a range of 0.5 up to 2.0 kGy applied doses were also evaluated. No differences were verified in the overall of sensorial and physical properties after irradiation up to 1 kGy, a decrease of natural microbiota was noticed (⩾2 log). Based on the determined D10, the amount of radiation necessary to kill 10 5E. coli and L. innocua was between 0.70 and 1.55 kGy. Shelf life of irradiated coriander, mint and lettuce at 0.5 kGy increased 2, 3 and 4 days, respectively, when compared with non-irradiated.

  3. Vegetation modulated landscape evolution: Effects of vegetation on landscape processes, drainage density and topography

    NASA Astrophysics Data System (ADS)

    Bras, R. L.; Istanbulluoglu, E.

    2004-12-01

    Topography acts as a template for numerous landscape processes that includes hydrologic, ecologic and biologic phenomena. These processes not only interact with each other but also contribute to shaping the landscape as they influence geomorphic processes. We have investigated the effects of vegetation on known geomorphic relations, thresholds for channel initiation and landform evolution, using both analytical and numerical approaches. Vegetation is assumed to form a uniform ground cover. Runoff erosion is modeled based on power function of excess shear stress, in which shear stress efficiency is inversely proportional to vegetation cover. Plant effect on slope stability is represented by additional cohesion provided by plant roots. Vegetation cover is assumed to reduce sediment transport rates due to physical creep processes (rainsplash, dry ravel, and expansion and contraction of sediments) according to a negative exponential relationship. Vegetation grows as a function of both available cover and unoccupied space by plants, and is killed by geomorphic disturbances (runoff erosion and landsliding), and wildfires. Analytical results suggest that, in an equilibrium basin with a fixed vegetation cover, plants may cause a transition in the dominant erosion process at the channel head. A runoff erosion dominated landscape, under none or loose vegetation cover, may become landslide dominated under a denser vegetation cover. The sign of the predicted relationship between drainage density and vegetation cover depends on the relative influence of vegetation on different erosion phenomena. With model parameter values representative of the Oregon Coast Range (OCR), numerical experiments conducted using the CHILD model. Numerical experiments reveal the importance of vegetation disturbances on the landscape structure. Simulated landscapes resemble real-world catchments in the OCR when vegetation disturbances are considered.

  4. Vegetation-modulated landscape evolution: Effects of vegetation on landscape processes, drainage density, and topography

    NASA Astrophysics Data System (ADS)

    Istanbulluoglu, Erkan; Bras, Rafael L.

    2005-06-01

    Topography acts as a template for numerous landscape processes that include hydrologic, ecologic, and biologic phenomena. These processes not only interact with each other but also contribute to shaping the landscape as they influence geomorphic processes. We have investigated the effects of vegetation on thresholds for channel initiation and landform evolution using both analytical and numerical approaches. Vegetation is assumed to form a uniform ground cover. Runoff erosion is modeled based on a power function of excess shear stress, in which shear stress efficiency is inversely proportional to vegetation cover. This approach is validated using data. Plant effect on slope stability is represented by additional cohesion provided by plant roots. Vegetation cover is assumed to reduce sediment transport rates due to physical creep processes (rainsplash, dry ravel, and expansion and contraction of sediments) according to a negative exponential relationship. Vegetation grows as a function of both available cover and unoccupied space by plants and is killed by geomorphic disturbances (runoff erosion and landsliding) and wildfires. Analytical results suggest that in an equilibrium basin with a fixed vegetation cover, plants may cause a transition in the dominant erosion process at the channel head. A runoff erosion-dominated landscape, under none or poor vegetation cover, may become landslide dominated under a denser vegetation cover. The sign of the predicted relationship between drainage density and vegetation cover depends on the relative influence of vegetation on different erosion phenomena. With model parameter values representative of the Oregon Coast Range (OCR), numerical experiments conducted using the Channel Hillslope Integrated Landscape Development (CHILD) model confirm the findings based on the analytical theory. A highly dissected fluvial landscape emerges when surface is assumed bare. When vegetation cover is modeled, landscape relief increases

  5. U.S. Fruit and Vegetable Processing Industries.

    ERIC Educational Resources Information Center

    Buckley, Katharine C.; And Others

    Because of shifts in consumer tastes and preferences, demographics, technology, government regulation, and the expanding interdependence of world markets, the United States fruit and vegetable processing industries must operate in a constantly changing and uncertain economic environment. U.S. per capita use of processed fruits and vegetables is…

  6. Coatings for minimally processed fruits and vegetables

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fresh-cut fruit and vegetables are gaining increasing popularity and market share. Techniques to enhance stability of fresh cut produce are reviewed. Among these techniques, edibles coatings can provide protection against dehydration, microbial decay and decrease events related to physiological sene...

  7. Role of vegetation on erosion processes: experimental investigation

    NASA Astrophysics Data System (ADS)

    Termini, Donatella

    2014-05-01

    Investigations on soil-system ecology are ever more oriented toward quantitative information based on the study of the linkages between physical processes and ecological response in rivers. As it is known, in presence of vegetation, the hydrodynamics characteristics of flow are principally determined by the mutual interrelation between the flow velocity field and the hydraulic behavior (completely submerged or emergent) of the vegetation elements. Much effort has been made toward identifying the theoretical law to interpret the vertical profile of flow longitudinal velocity in vegetated channels. Many theoretical and experimental studies in laboratory channels have been carried out and especially the case of submerged flexible vegetation has been examined (Termini, 2012). The effects of vegetation on flow velocity are significant and of crucial importance for stabilizing sediments and reducing erosion. Vegetation has a complex effect on walls roughness and the study of the hydrodynamic conditions of flow is difficult. Although most studies based on the "boundary layer" scheme so that the hydrodynamic conditions inside and above the vegetated layer are considered separately, some authors (Ghisalberti and Nepft, 2002; Carollo et al., 2008) claim that the "mixing layer" scheme is more appropriate to define the velocity profile both inside and outside the vegetated layer. Experimental program has been recently carried out in two laboratory flumes constructed at the laboratory of Dipartimento di Ingegneria Civile, Ambientale, Aerospaziale, dei Materiali - University of Palermo (Italy) with real and flexible vegetation on the bed. In this paper, attention is paid to the influence of vegetation on the erosion processes both on the bed and on the channel banks. The structure of the detailed flow velocity field is analyzed and compared with that obtained in absence of vegetation. Attention is then devoted to the analysis of soil erosion mechanism. Carollo F.G., Ferro V

  8. Dynamic Iodine Uptake Process in Vegetation Labeled by I-125

    NASA Astrophysics Data System (ADS)

    Weng, H.; Yan, A.; Hong, C.; Qin, Y.; Xie, L.

    2005-12-01

    Low iodine in vegetation is responsible for the occurrence of iodine deficiency in human body. It is of important scientific and practical implications to thoroughly understand the absorption and accumulation process of iodine in vegetation and to seek efficient pathways supplementing iodine for human health. Through aquaculture trial of green vegetable, the dynamic absorption process of I-125, as an isotopic tracer, and its accumulation and distribution in vegetable are studied. The results show that, after green vegetable is aqua-cultured for 5 min, micro I-125 can be monitored in root and after 10 min, it is also monitored in leaves, which indicates a rapid absorption and transportation. As culture time continues, I-125 in root, stem and leaves apparently increases, but the content distribution is differing. Most of the I-125 absorbed by green vegetable is enriched in root, and only one fourth of the total amount is transported upwards and mainly distributes in stem. The content of I-125 in leaves accounts for 5% which is mainly accumulated around the leaf margin. I-125 uptake in stem is larger at night than at daylight, whereas in leaves, its uptake is lower at night than at daylight, suggesting that iodine uptake is an active process and its transportation and accumulation process is related to photosynthesis.

  9. Effect of flexible vegetation on localized erosion processes

    NASA Astrophysics Data System (ADS)

    Termini, Donatella

    2013-04-01

    The knowledge of the hydraulic characteristics of flow over vegetation is very important to support the management of fluvial processes. The effects of vegetation on flow velocity are significant and of crucial importance for stabilizing sediments and reducing erosion along the channel. But, because of the temporal changing of roughness due to natural vegetative growth, the response of vegetation to the flow can change in time. Thus, vegetation has a complex effect on walls roughness and the study of the hydrodynamic conditions of flow is difficult. Many theoretical and experimental investigations have been performed in order to analyze both the mean flow and turbulence structure of open-channel flow (Nezu and Rodi 1986; Ghisalberti and Nepf, 2002). Recent experimental runs carried out in laboratory channels with flexible vegetation, realized by using artificial filaments (Kutija and Hong 1996; Ikeda and Kanazawa 1996), investigated some peculiar characteristics of flow turbulence structure and revealed the generation of periodic organized vortices whose center is located slightly above the top of the vegetation layer. Ghisalberti and Nepf (2002) confirmed the formation of such vortices, highlighting that, in the case of flexible vegetation, the vortex-driven oscillation of velocity drives coherent vegetation waving, producing a spatially and temporally variable drag force. In this paper, attention is paid to the influence of vegetation on the erosion processes both on the bed and on the channel banks. Experiments were carried out both in a straight channel and in a meandering channel, both constructed at the Department of Civil, Environmental, Aerospatial and of Materials (DICAM) - University of Palermo (Italy). The formation of turbulence structures inside the vegetated layer is verified, providing some insight into the mechanisms of sediment transport. Nezu, I. & Rodi, W. 1986. Open-channel flow measurements with a Laser Doppler Anemometer. Journal of Hydraulic

  10. EFFECTS OF GEOMORPHIC PROCESSES AND HYDROLOGIC REGIMES ON RIPARIAN VEGETATION

    EPA Science Inventory

    In this chapter, the relationships among riparian vegetation and geomorphic and hydrologic processes in central Great Basin watersheds are evaluated over a range of scales. These relationships are examined through a series of case studies that have been conducted by the Great Ba...

  11. Pulsed electric field processing for fruit and vegetables

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This month’s column reviews the theory and current applications of pulsed electric field (PEF) processing for fruits and vegetables to improve their safety and quality. This month’s column coauthor, Stefan Toepfl, is advanced research manager at the German Institute of Food Technologies and professo...

  12. Process for producing vegetative and tuber growth regulator

    NASA Technical Reports Server (NTRS)

    Stutte, Gary W. (Inventor); Yorio, Neil C. (Inventor)

    1999-01-01

    A process of making a vegetative and tuber growth regulator. The vegetative and tuber growth regulator is made by growing potato plants in a recirculating hydroponic system for a sufficient time to produce the growth regulator. Also, the use of the vegetative and growth regulator on solanaceous plants, tuber forming plants and ornamental seedlings by contacting the roots or shoots of the plant with a sufficient amount of the growth regulator to regulate the growth of the plant and one more of canopy size, plant height, stem length, internode number and presence of tubers in fresh mass. Finally, a method for regulating the growth of potato plants using a recirculating hydroponic system is described.

  13. Preliminary process engineering evaluation of ethanol production from vegetative crops

    NASA Astrophysics Data System (ADS)

    Moreira, A. R.; Linden, J. C.; Smith, D. H.; Villet, R. H.

    1982-12-01

    Vegetative crops show good potential as feedstock for ethanol production via cellulose hydrolysis and yeast fermentation. The low levels of lignin encountered in young plant tissues show an inverse relationship with the high cellulose digestibility during hydrolysis with cellulose enzymes. Ensiled sorghum species and brown midrib mutants of sorghum exhibit high glucose yields after enzyme hydrolysis as well. Vegetative crop materials as candidate feedstocks for ethanol manufacture should continue to be studied. The species studied so far are high value cash crops and result in relatively high costs for the final ethanol product. Unconventional crops, such as pigweed, kochia, and Russian thistle, which can use water efficiently and grow on relatively arid land under conditions not ideal for food production, should be carefully evaluated with regard to their cultivation requirements, photosynthesis rates, and cellulose digestibility. Such crops should result in more favorable process economics for alcohol production.

  14. Optimization of biodiesel production process using recycled vegetable oil

    NASA Astrophysics Data System (ADS)

    Lugo, Yarely

    Petro diesel toxic emissions and its limited resources have created an interest for the development of new energy resources, such as biodiesel. Biodiesel is traditionally produced by a transesterification reaction between vegetable oil and an alcohol in the presence of a catalyst. However, this process is slow and expensive due to the high cost of raw materials. Low costs feedstock oils such as recycled and animal fats are available but they cannot be transesterified with alkaline catalysts due to high content of free fatty acids, which can lead to undesirable reactions such as saponification. In this study, we reduce free fatty acids content by using an acid pre-treatment. We compare sulfuric acid, hydrochloric acid and ptoluenesulfonic acid (PTSA) to pre-treat recycled vegetable oil. PTSA removes water after 60 minutes of treatment at room temperature or within 15 minutes at 50°C. The pretreatment was followed by a transesterification reaction using alkaline catalyst. To minimize costs and accelerate reaction, the pretreatment and transesterification reaction of recycle vegetable oil was conducted at atmospheric pressure in a microwave oven. Biodiesel was characterized using a GC-MS method.

  15. Effect of Processing on Magnesium Content of Green Leafy Vegetables

    NASA Astrophysics Data System (ADS)

    Rai, D.; Agrawal, R.; Kumar, R.; Rai, A. Kumar; Rai, G. Kumar

    2014-01-01

    In the present paper, we have studied the effect of different food processing techniques like blanching, microwave processing, boiling, frying, and different drying methods on depletion of minerals especially magnesium in green leafy vegetables (leaves of Trigonella foenum, common name methi, and Spinacia oleracea, common name spinach) using laser-induced breakdown spectroscopy (LIBS). These processing techniques are frequently used at home as well as in food processing industries. The LIBS spectra of the fresh leaves of methi and spinach and their pellets (made by drying, grinding, and pressing the leaf) were recorded in a spectral range from 200 to 500 nm. After applying the above processing techniques, different pellets of these leaves were made in the same way. The LIBS spectra of these processed leaf samples were also recorded using the same experimental parameters as used for the fresh samples. Our results show that among the above processing techniques, frying most significantly reduces the content of magnesium, whereas the least loss of Mg is observed in the case of boiling. We have verified this result by recording the LIBS spectra of the intact fresh leaves and of those processed with different techniques. The same results were also obtained from the LIBS spectra of the intact leaves and their pellets. The LIBS spectra of methi and spinach leaves were also recorded after drying them using two different techniques — drying in vacuum and in a hot air oven; the results show that vacuum drying is more suitable in terms of minimizing loss of Mg content in leaves.

  16. 21 CFR 133.174 - Pasteurized process cheese food with fruits, vegetables, or meats.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ..., vegetables, or meats. 133.174 Section 133.174 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... with fruits, vegetables, or meats. (a) Pasteurized process cheese food with fruits, vegetables, or meats, or mixtures of these is the food which conforms to the definition and standard of identity,...

  17. 21 CFR 133.180 - Pasteurized process cheese spread with fruits, vegetables, or meats.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ..., vegetables, or meats. 133.180 Section 133.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... with fruits, vegetables, or meats. (a) Pasteurized process cheese spread with fruits, vegetables, or meats, or mixtures of these is a food which conforms to the definition and standard of identity, and...

  18. 21 CFR 133.174 - Pasteurized process cheese food with fruits, vegetables, or meats.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ..., vegetables, or meats. 133.174 Section 133.174 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... with fruits, vegetables, or meats. (a) Pasteurized process cheese food with fruits, vegetables, or meats, or mixtures of these is the food which conforms to the definition and standard of identity,...

  19. 21 CFR 133.174 - Pasteurized process cheese food with fruits, vegetables, or meats.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ..., vegetables, or meats. 133.174 Section 133.174 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... with fruits, vegetables, or meats. (a) Pasteurized process cheese food with fruits, vegetables, or meats, or mixtures of these is the food which conforms to the definition and standard of identity,...

  20. 21 CFR 133.174 - Pasteurized process cheese food with fruits, vegetables, or meats.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ..., vegetables, or meats. 133.174 Section 133.174 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... with fruits, vegetables, or meats. (a) Pasteurized process cheese food with fruits, vegetables, or meats, or mixtures of these is the food which conforms to the definition and standard of identity,...

  1. 21 CFR 133.180 - Pasteurized process cheese spread with fruits, vegetables, or meats.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ..., vegetables, or meats. 133.180 Section 133.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... with fruits, vegetables, or meats. (a) Pasteurized process cheese spread with fruits, vegetables, or meats, or mixtures of these is a food which conforms to the definition and standard of identity, and...

  2. 21 CFR 133.180 - Pasteurized process cheese spread with fruits, vegetables, or meats.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ..., vegetables, or meats. 133.180 Section 133.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... with fruits, vegetables, or meats. (a) Pasteurized process cheese spread with fruits, vegetables, or meats, or mixtures of these is a food which conforms to the definition and standard of identity, and...

  3. 21 CFR 133.180 - Pasteurized process cheese spread with fruits, vegetables, or meats.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ..., vegetables, or meats. 133.180 Section 133.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... with fruits, vegetables, or meats. (a) Pasteurized process cheese spread with fruits, vegetables, or meats, or mixtures of these is a food which conforms to the definition and standard of identity, and...

  4. 21 CFR 133.174 - Pasteurized process cheese food with fruits, vegetables, or meats.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ..., vegetables, or meats. 133.174 Section 133.174 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... with fruits, vegetables, or meats. (a) Pasteurized process cheese food with fruits, vegetables, or meats, or mixtures of these is the food which conforms to the definition and standard of identity,...

  5. 21 CFR 133.180 - Pasteurized process cheese spread with fruits, vegetables, or meats.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ..., vegetables, or meats. 133.180 Section 133.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... with fruits, vegetables, or meats. (a) Pasteurized process cheese spread with fruits, vegetables, or meats, or mixtures of these is a food which conforms to the definition and standard of identity, and...

  6. Fluvial processes and vegetation — Glimpses of the past, the present, and perhaps the future

    NASA Astrophysics Data System (ADS)

    Osterkamp, W. R.; Hupp, C. R.

    2010-04-01

    Most research before 1960 into interactions among fluvial processes, resulting landforms, and vegetation was descriptive. Since then, however, research has become more detailed and quantitative permitting numerical modeling and applications including agricultural-erosion abatement and rehabilitation of altered bottomlands. Although progress was largely observational, the empiricism increasingly yielded to objective recognition of how vegetation interacts with and influences geomorphic process. A review of advances relating fluvial processes and vegetation during the last 50 years centers on hydrologic reconstructions from tree rings, plant indicators of flow- and flood-frequency parameters, hydrologic controls on plant species, regulation of sediment movement by vegetation, vegetative controls on mass movement, and relations between plant cover and sediment movement. Extension of present studies of vegetation as a regulator of bottomland hydrologic and geomorphic processes may become markedly more sophisticated and widespread than at present. Research emphases that are likely to continue include vegetative considerations for erosion modeling, response of riparian-zone forests to disturbance such as dams and water diversion, the effect of vegetation on channel and bottomland dynamics, and rehabilitation of stream corridors. Research topics that presently are receiving attention are the effect of woody vegetation on the roughness of stream corridors and, hence, processes of flood conveyance and flood-plain sedimentation, the development of a theoretical basis for rehabilitation projects as opposed to fully empirical approaches, the effect of invasive plant species on the dynamics of bottomland vegetation, the quantification of below-surface biomass and related soil-stability factors for use in erosion-prediction models, and the effect of impoundments on downstream narrowing of channels and accompanying encroachment of vegetation. Bottomland vegetation partially

  7. Fluvial processes and vegetation - Glimpses of the past, the present, and perhaps the future

    USGS Publications Warehouse

    Osterkamp, W.R.; Hupp, C.R.

    2010-01-01

    Most research before 1960 into interactions among fluvial processes, resulting landforms, and vegetation was descriptive. Since then, however, research has become more detailed and quantitative permitting numerical modeling and applications including agricultural-erosion abatement and rehabilitation of altered bottomlands. Although progress was largely observational, the empiricism increasingly yielded to objective recognition of how vegetation interacts with and influences geomorphic process. A review of advances relating fluvial processes and vegetation during the last 50 years centers on hydrologic reconstructions from tree rings, plant indicators of flow- and flood-frequency parameters, hydrologic controls on plant species, regulation of sediment movement by vegetation, vegetative controls on mass movement, and relations between plant cover and sediment movement. Extension of present studies of vegetation as a regulator of bottomland hydrologic and geomorphic processes may become markedly more sophisticated and widespread than at present. Research emphases that are likely to continue include vegetative considerations for erosion modeling, response of riparian-zone forests to disturbance such as dams and water diversion, the effect of vegetation on channel and bottomland dynamics, and rehabilitation of stream corridors. Research topics that presently are receiving attention are the effect of woody vegetation on the roughness of stream corridors and, hence, processes of flood conveyance and flood-plain sedimentation, the development of a theoretical basis for rehabilitation projects as opposed to fully empirical approaches, the effect of invasive plant species on the dynamics of bottomland vegetation, the quantification of below-surface biomass and related soil-stability factors for use in erosion-prediction models, and the effect of impoundments on downstream narrowing of channels and accompanying encroachment of vegetation. Bottomland vegetation partially

  8. Green processing for commercial production of feruloylated vegetable oils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Covalent incorporation of ferulic acid into vegetable oils produces a desirable product for cosmetic applications. Current practice involves the biocatalytic transesterification of ethyl ferulate with soybean oil, followed by a molecular distillation step to remove unconsumed ethyl ferulate and the...

  9. Coevolution of hydraulic, soil and vegetation processes in estuarine wetlands

    NASA Astrophysics Data System (ADS)

    Trivisonno, Franco; Rodriguez, Jose F.; Riccardi, Gerardo; Saco, Patricia; Stenta, Hernan

    2014-05-01

    Estuarine wetlands of south eastern Australia, typically display a vegetation zonation with a sequence mudflats - mangrove forest - saltmarsh plains from the seaward margin and up the topographic gradient. Estuarine wetlands are among the most productive ecosystems in the world, providing unique habitats for fish and many terrestrial species. They also have a carbon sequestration capacity that surpasess terrestrial forest. Estuarine wetlands respond to sea-level rise by vertical accretion and horizontal landward migration, in order to maintain their position in the tidal frame. In situations in which buffer areas for landward migration are not available, saltmarsh can be lost due to mangrove encroachment. As a result of mangrove invasion associated in part with raising estuary water levels and urbanisation, coastal saltmarsh in parts of south-eastern Australia has been declared an endangered ecological community. Predicting estuarine wetlands response to sea-level rise requires modelling the coevolving dynamics of water flow, soil and vegetation. This paper presents preliminary results of our recently developed numerical model for wetland dynamics in wetlands of the Hunter estuary of NSW. The model simulates continuous tidal inflow into the wetland, and accounts for the effect of varying vegetation types on flow resistance. Coevolution effects appear as vegetation types are updated based on their preference to prevailing hydrodynamic conditions. The model also considers that accretion values vary with vegetation type. Simulations are driven using local information collected over several years, which includes estuary water levels, accretion rates, soil carbon content, flow resistance and vegetation preference to hydraulic conditions. Model results predict further saltmarsh loss under current conditions of moderate increase of estuary water levels.

  10. 21 CFR 133.170 - Pasteurized process cheese with fruits, vegetables, or meats.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ..., or meats. 133.170 Section 133.170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... fruits, vegetables, or meats. (a) Unless a definition and standard of identity specifically applicable is established by another section of this part, a pasteurized process cheese with fruits, vegetables, or...

  11. 21 CFR 133.170 - Pasteurized process cheese with fruits, vegetables, or meats.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ..., or meats. 133.170 Section 133.170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... fruits, vegetables, or meats. (a) Unless a definition and standard of identity specifically applicable is established by another section of this part, a pasteurized process cheese with fruits, vegetables, or...

  12. 21 CFR 133.170 - Pasteurized process cheese with fruits, vegetables, or meats.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ..., or meats. 133.170 Section 133.170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... fruits, vegetables, or meats. (a) Unless a definition and standard of identity specifically applicable is established by another section of this part, a pasteurized process cheese with fruits, vegetables, or...

  13. 21 CFR 133.170 - Pasteurized process cheese with fruits, vegetables, or meats.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ..., or meats. 133.170 Section 133.170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... fruits, vegetables, or meats. (a) Unless a definition and standard of identity specifically applicable is established by another section of this part, a pasteurized process cheese with fruits, vegetables, or...

  14. 21 CFR 133.170 - Pasteurized process cheese with fruits, vegetables, or meats.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ..., or meats. 133.170 Section 133.170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... fruits, vegetables, or meats. (a) Unless a definition and standard of identity specifically applicable is established by another section of this part, a pasteurized process cheese with fruits, vegetables, or...

  15. 7 CFR 318.13-14 - Movement of processed fruits, vegetables, and other products.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... other products that have not been processed sufficiently as to be incapable of harboring fruit flies are subject to the interstate movement requirements which apply to the fruit, vegetable, or other product...

  16. 7 CFR 318.13-14 - Movement of processed fruits, vegetables, and other products.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... other products that have not been processed sufficiently as to be incapable of harboring fruit flies are subject to the interstate movement requirements which apply to the fruit, vegetable, or other product...

  17. 7 CFR 318.13-14 - Movement of processed fruits, vegetables, and other products.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... other products that have not been processed sufficiently as to be incapable of harboring fruit flies are subject to the interstate movement requirements which apply to the fruit, vegetable, or other product...

  18. 7 CFR 318.13-14 - Movement of processed fruits, vegetables, and other products.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... other products that have not been processed sufficiently as to be incapable of harboring fruit flies are subject to the interstate movement requirements which apply to the fruit, vegetable, or other product...

  19. 7 CFR 318.13-14 - Movement of processed fruits, vegetables, and other products.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... other products that have not been processed sufficiently as to be incapable of harboring fruit flies are subject to the interstate movement requirements which apply to the fruit, vegetable, or other product...

  20. 7 CFR 319.56-11 - Importation of dried, cured, or processed fruits, vegetables, nuts, and legumes.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Importation of dried, cured, or processed fruits... QUARANTINE NOTICES Fruits and Vegetables § 319.56-11 Importation of dried, cured, or processed fruits, vegetables, nuts, and legumes. (a) Dried, cured, or processed fruits and vegetables (except frozen fruits...

  1. 7 CFR 319.56-11 - Importation of dried, cured, or processed fruits, vegetables, nuts, and legumes.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 5 2013-01-01 2013-01-01 false Importation of dried, cured, or processed fruits... QUARANTINE NOTICES Fruits and Vegetables § 319.56-11 Importation of dried, cured, or processed fruits, vegetables, nuts, and legumes. (a) Dried, cured, or processed fruits and vegetables (except frozen fruits...

  2. 7 CFR 319.56-11 - Importation of dried, cured, or processed fruits, vegetables, nuts, and legumes.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 5 2012-01-01 2012-01-01 false Importation of dried, cured, or processed fruits... QUARANTINE NOTICES Fruits and Vegetables § 319.56-11 Importation of dried, cured, or processed fruits, vegetables, nuts, and legumes. (a) Dried, cured, or processed fruits and vegetables (except frozen fruits...

  3. 7 CFR 319.56-11 - Importation of dried, cured, or processed fruits, vegetables, nuts, and legumes.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 5 2014-01-01 2014-01-01 false Importation of dried, cured, or processed fruits... QUARANTINE NOTICES Fruits and Vegetables § 319.56-11 Importation of dried, cured, or processed fruits, vegetables, nuts, and legumes. (a) Dried, cured, or processed fruits and vegetables (except frozen fruits...

  4. 7 CFR 319.56-11 - Importation of dried, cured, or processed fruits, vegetables, nuts, and legumes.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 5 2011-01-01 2011-01-01 false Importation of dried, cured, or processed fruits... QUARANTINE NOTICES Fruits and Vegetables § 319.56-11 Importation of dried, cured, or processed fruits, vegetables, nuts, and legumes. (a) Dried, cured, or processed fruits and vegetables (except frozen fruits...

  5. Anaerobic digestion and co-digestion processes of vegetable and fruit residues: process and microbial ecology.

    PubMed

    Garcia-Peña, E I; Parameswaran, P; Kang, D W; Canul-Chan, M; Krajmalnik-Brown, R

    2011-10-01

    This study evaluated the feasibility of methane production from fruit and vegetable waste (FVW) obtained from the central food distribution market in Mexico City using an anaerobic digestion (AD) process. Batch systems showed that pH control and nitrogen addition had significant effects on biogas production, methane yield, and volatile solids (VS) removal from the FVW (0.42 m(biogas)(3)/kg VS, 50%, and 80%, respectively). Co-digestion of the FVW with meat residues (MR) enhanced the process performance and was also evaluated in a 30 L AD system. When the system reached stable operation, its methane yield was 0.25 (m(3)/kg TS), and the removal of the organic matter measured as the total chemical demand (tCOD) was 65%. The microbial population (general Bacteria and Archaea) in the 30 L system was also determined and characterized and was closely correlated with its potential function in the AD system. PMID:21865034

  6. Inundation, Wetland Vegetation and Biogeochemical Processes in the Amazon Basin

    NASA Astrophysics Data System (ADS)

    Melack, J. M.; Hess, L. L.; Hamilton, S. K.; Richey, J. E.; Novo, E. M.

    2001-12-01

    Remote sensing of the Amazon basin with passive and active microwave techniques were applied to determine the temporally varying extent of inundation and associated vegetation, and used in conjunction with field measurements to calculate regional rates of carbon dioxide emission from wetlands to the atmosphere. Monthly inundation areas were derived from analysis of the 37-GHz polarization difference observed by the Scanning Multichannel Microwave Radiometer (1979 to 1987) for the mainstem Amazon floodplain in Brazil, the Llanos de Moxos (Beni and Mamore rivers) in Bolivia, the Bananal Island (Araguaia River) and Roraima savannas. Maximum areas subject to inundation, including permanent open waters in rivers and lakes, were as follows (in km2): mainstem Amazon 97,400; Moxos 92,000; Bananal 58,500, and Roraima 16,500. Data from the Japanese Earth Resources Satellite-1, L-band synthetic aperture radar were used to determine inundation and wetland vegetation for a quadrat in the central Amazon basin (0o N to 8o S, 72o W to 54o W) at high water (May-June 1996) and low water (October 1995). Flooded area of rivers and floodplains (> 100 m in width) ranged from 79,000 km2 to 290,000 km2. When combined with estimates of inundation associated with streams not detected by the radar, a maximum area of 350,000 km2 (or 20% of the quadrat) was flooded. Combining the areal extent of flooding and measurements of free dissolved CO2 with an evasion model leads to outgassing of CO2 from inundated surfaces to the atmosphere in the central Amazon of 1.1 plus or minus 0.2 MgC ha-1 y-1. Extrapolated over the whole basin, the flux is 10 times the fluvial export of organic carbon to the ocean.

  7. How Riparian Vegetation Influences Stream Morphology and Process: Implications for Restoration

    NASA Astrophysics Data System (ADS)

    Pizzuto, J. E.

    2005-05-01

    Vegetation is often used to enhance bank stabilization efforts and as part of more generalized restoration designs, but the influence of vegetation on geomorphic processes is poorly understood. Recent research suggests that changes in riparian vegetation can influence channel morphology, rates of erosion and deposition, and by extension, the entire sediment budget of a reach. In recent studies in the Mid-Atlantic region, reaches with forested riparian vegetation were compared to immediately adjacent non-forested (grassy) riparian vegetation to explain why channels with forested vegetation are wider than their non-forested counterparts. At study sites, erosion occurs at cutbanks in curving reaches, while deposition is localized on active floodplains at the insides of bends. In narrow, non-forested reaches, rates of bank erosion and channel migration are high, while in wide, forested reaches, rates of bank erosion and channel migration are low. These results may be explained using the ratio of two dimensionless parameters, alpha and E. Alpha represents the influence of vegetation on rates of active floodplain deposition (it is very high in non-forested reaches, and very low in forested reaches), while E is proportional to rates of cutbank migration (it is high in non-forested areas and low in forested areas). The width is proportional to E/alpha. These results could lead to improved assessment of the geomorphic effects of restoration designs that involve changes in riparian vegetation.

  8. Patterns and Processes in Southwestern shrublands and grasslands: role of vegetation, soil- geomorphology, and overland flow

    NASA Astrophysics Data System (ADS)

    Bedford, D. R.; Small, E. E.; E, T. G.

    2007-12-01

    Pattern of variable soil properties have been linked to vegetation as well as soil-landform characteristics and processes. It has been long hypothesized that patterns of infiltration and overland flow play key roles in arid and semi-arid region ecohydrology. Specifically, the process of redistribution of water and sediments have been linked to vegetation related feedbacks that enable persistence of vegetation in water limited environments. Yet, the processes of redistribution, such as through runoff and surface ponding, have been poorly described or documented. We have documented that the spatial pattern of soil properties is dependant on the vegetation pattern as well as the type of, and in some cases location within a, landform. These patterns are likely due to feedbacks between vegetation and the surface processes that affect soil properties and therefore water availability. In this paper, we present observations and numerical simulation that show how patterns of overland flow and infiltration are affected by vegetation-topography related patterns of soil properties. We have developed a numerical model that works on 10 cm grid cells that can inform on the processes of infiltration and overland flow over continuously varying soil properties. We use this model to show how the patterns of soil properties affect runoff, as well as the conditions under which redistribution via runon and ponding can occur. Furthermore, we show using data from a central New Mexico grassland and shrubland, and an eastern Mojave Desert shrubland how climatic differences can affect the patterns of infiltration and runoff.

  9. Intelligent image processing for vegetation classification using multispectral LANDSAT data

    NASA Astrophysics Data System (ADS)

    Santos, Stewart R.; Flores, Jorge L.; Garcia-Torales, G.

    2015-09-01

    We propose an intelligent computational technique for analysis of vegetation imaging, which are acquired with multispectral scanner (MSS) sensor. This work focuses on intelligent and adaptive artificial neural network (ANN) methodologies that allow segmentation and classification of spectral remote sensing (RS) signatures, in order to obtain a high resolution map, in which we can delimit the wooded areas and quantify the amount of combustible materials present into these areas. This could provide important information to prevent fires and deforestation of wooded areas. The spectral RS input data, acquired by the MSS sensor, are considered in a random propagation remotely sensed scene with unknown statistics for each Thematic Mapper (TM) band. Performing high-resolution reconstruction and adding these spectral values with neighbor pixels information from each TM band, we can include contextual information into an ANN. The biggest challenge in conventional classifiers is how to reduce the number of components in the feature vector, while preserving the major information contained in the data, especially when the dimensionality of the feature space is high. Preliminary results show that the Adaptive Modified Neural Network method is a promising and effective spectral method for segmentation and classification in RS images acquired with MSS sensor.

  10. Synergies of carvacrol and 1,8-cineole to inhibit bacteria associated with minimally processed vegetables.

    PubMed

    de Sousa, Jossana Pereira; de Azerêdo, Geíza Alves; de Araújo Torres, Rayanne; da Silva Vasconcelos, Margarida Angélica; da Conceição, Maria Lúcia; de Souza, Evandro Leite

    2012-03-15

    This study assessed the occurrence of an enhancing inhibitory effect of the combined application of carvacrol and 1,8-cineole against bacteria associated with minimally processed vegetables using the determination of Fractional Inhibitory Concentration (FIC) index, time-kill assay in vegetable broth and application in vegetable matrices. Their effects, individually and in combination, on the sensory characteristics of the vegetables were also determined. Carvacrol and 1,8-cineole displayed Minimum Inhibitory Concentration (MIC) in a range of 0.6-2.5 and 5-20 μL/mL, respectively, against the organisms studied. FIC indices of the combined application of the compounds were 0.25 against Listeria monocytogenes, Aeromonas hydrophila and Pseudomonas fluorescens, suggesting a synergic interaction. Application of carvacrol and 1,8-cineole alone (MIC) or in a mixture (1/8 MIC+1/8 MIC or 1/4 MIC+1/4 MIC) in vegetable broth caused a significant decrease (p<0.05) in bacterial count over 24h. Mixtures of carvacrol and 1,8-cineole reduced (p<0.05) the inocula of all bacteria in vegetable broth and in experimentally inoculated fresh-cut vegetables. A similar efficacy was observed in the reduction of naturally occurring microorganisms in vegetables. Sensory evaluation revealed that the scores of the most-evaluated attributes fell between "like slightly" and "neither like nor dislike." The combination of carvacrol and 1,8-cineole at sub-inhibitory concentrations could constitute an interesting approach to sanitizing minimally processed vegetables. PMID:22273461

  11. Connectivity processes and riparian vegetation of the upper Paraná River, Brazil

    NASA Astrophysics Data System (ADS)

    Stevaux, José C.; Corradini, Fabrício A.; Aquino, Samia

    2013-10-01

    In fluvial systems, the relationship between a dominant variable (e.g. flood pulse) and its dependent ones (e.g. riparian vegetation) is called connectivity. This paper analyzes the connectivity elements and processes controlling riparian vegetation for a reach of the upper Paraná River (Brazil) and estimates the future changes in channel-vegetation relationship as a consequence of the managing of a large dam. The studied reach is situated 30 km downstream from the Porto Primavera Dam (construction finished in 1999). Through aerial photography (1:25,000, 1996), RGB-CBERS satellite imagery and a previous field botany survey it was possible to elaborate a map with the five major morpho-vegetation units: 1) Tree-dominated natural levee, 2) Shrubby upper floodplain, 3) Shrub-herbaceous mid floodplain, 4) Grass-herbaceous lower floodplain and 5) Shrub-herbaceous flood runoff channel units. By use of a detailed topographic survey and statistical tools each morpho-vegetation type was analyzed according to its connectivity parameters (frequency, recurrence, permanence, seasonality, potamophase, limnophase and FCQ index) in the pre- and post-dam closure periods of the historical series. Data showed that most of the morpho-vegetation units were predicted to present changes in connectivity parameters values after dam closing and the new regime could affect, in different intensity, the river ecology and particularly the riparian vegetation. The methods used in this study can be useful for dam impact studies in other South American tropical rivers.

  12. Click chemistry approach to conventional vegetable tanning process: accelerated method with improved organoleptic properties.

    PubMed

    Krishnamoorthy, Ganesan; Ramamurthy, Govindaswamy; Sadulla, Sayeed; Sastry, Thotapalli Parvathaleswara; Mandal, Asit Baran

    2014-09-01

    Click chemistry approaches are tailored to generate molecular building blocks quickly and reliably by joining small units together selectively and covalently, stably and irreversibly. The vegetable tannins such as hydrolyzable and condensed tannins are capable to produce rather stable radicals or inhibit the progress of radicals and are prone to oxidations such as photo and auto-oxidation, and their anti-oxidant nature is well known. A lot remains to be done to understand the extent of the variation of leather stability, color variation (lightening and darkening reaction of leather), and poor resistance to water uptake for prolonged periods. In the present study, we have reported click chemistry approaches to accelerated vegetable tanning processes based on periodates catalyzed formation of oxidized hydrolysable and condensed tannins for high exhaustion with improved properties. The distribution of oxidized vegetable tannin, the thermal stability such as shrinkage temperature (T s) and denaturation temperature (T d), resistance to collagenolytic activities, and organoleptic properties of tanned leather as well as the evaluations of eco-friendly characteristics were investigated. Scanning electron microscopic analysis indicates the cross section of tightness of the leather. Differential scanning calorimetric analysis shows that the T d of leather is more than that of vegetable tanned or equal to aldehyde tanned one. The leathers exhibited fullness, softness, good color, and general appearance when compared to non-oxidized vegetable tannin. The developed process benefits from significant reduction in total solids and better biodegradability in the effluent, compared to non-oxidized vegetable tannins. PMID:24888617

  13. 75 FR 11147 - Process for Requesting a Variance From Vegetation Standards for Levees and Floodwalls

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-10

    ... period. SUMMARY: In the February 9, 2010 issue of the Federal Register (75 FR 6364), the U.S. Army Corps of Engineers (Corps), published its proposed update to its current process for requesting a variance... Department of the Army, Corps of Engineers Process for Requesting a Variance From Vegetation Standards...

  14. Feedbacks between aeolian processes, vegetation productivity, and nutrient flux in deserts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wind is a key abiotic factor that influences the dynamics of arid and semiarid systems. A series of experiments and models will be presented that show the important feedbacks that exist between Aeolian processes and biotic process in deserts. Wind impacts vegetation by both changing the composition ...

  15. Housing Seasonal Workers for the Minnesota Processed Vegetable Industry

    ERIC Educational Resources Information Center

    Ziebarth, Ann

    2006-01-01

    The place where we live and work is a reflection of a complex set of economic conditions and social relationships. Very little information is available regarding housing for Minnesota's migrant workers. It is estimated that approximately 20,000 people migrate to Minnesota each summer to work in the production and processing of green peas and sweet…

  16. Computer and control applications in a vegetable processing plant

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There are many advantages to the use of computers and control in food industry. Software in the food industry takes 2 forms - general purpose commercial computer software and software for specialized applications, such as drying and thermal processing of foods. Many applied simulation models for d...

  17. Experimental observation of the rule of flexible vegetation on erosion processes

    NASA Astrophysics Data System (ADS)

    Termini, D.

    2012-04-01

    Vegetation altering hydrodynamic conditions of an open channel flow controls the exchanges of sediment, nutrients and contaminants. Thus, the knowledge of the hydraulic characteristics of flow over vegetation is very important to support the management of fluvial processes. But, the analysis of the hydrodynamic conditions is complex because vegetation is flexible in varying degrees and it oscillates in the flow changing position. Furthermore, because of temporal changing of roughness due to natural vegetative growth, the response of vegetation to the flow can change in time. Many theoretical and experimental investigations have been performed in order to analyze both the mean flow and turbulence structure of open-channel flow (Nezu and Rodi 1986; Lemmin and Rolland 1997; Shvidchenko and Pender 2001; Ghisalberti and Nepf, 2002). Recent experimental runs carried out in laboratory channels with flexible vegetation, realized by using artificial filaments (Kutija and Hong 1996; Ikeda and Kanazawa 1996), investigated some peculiar characteristics of flow turbulence structure and revealed the generation of periodic organized vortices whose center is located slightly above the top of the vegetation layer. On the other hand, recent experimental studies conducted by Termini and Sammartano (2012) in a mobile-bed laboratory channel, and in absence of vegetation, have demonstrated that the formation of coherent turbulence structures plays an important role in sediment transport and in scouring evolution. In particular, ejection and sweep events contribute significantly to erosion, deposition and sediment suspension. In this paper, in order to give a contribution to the understanding of the rule of vegetation on the analyzed erosion process, experimental results obtained in the same laboratory channel, but with bed covered by flexible vegetation, are presented. Attention is paid to interaction vegetation/erosion both along the vegetated-bed channel reach and downstream of it. In

  18. The influence of badland surfaces and erosion processes on vegetation cover

    NASA Astrophysics Data System (ADS)

    Hardenbicker, Ulrike; Matheis, Sarah

    2014-05-01

    To assess the links between badland geomorphology and vegetation cover, we used detailed mapping in the Avonlea badlands, 60 km southwest of Regina, Saskatchewan Canada. Three badlands surfaces are typical in the study area: a basal pediment surface, a mid-slope of bentonitic mudstone with typical popcorn surface, and an upper slope with mud-cemented sandstone. Badland development was triggered by rapid post Pleistocene incision of a meltwater channel in Upper Cretaceous marine and lagoonal sediments. After surveying and mapping of a test area, sediment samples were taken to analyze geophysical parameters. A detailed geomorphic map and vegetation map (1:1000) were compared and analyzed in order to determine the geomorphic environment for plant colonization. The shrink-swell capacity of the bentonitic bedrock, slaking potential and dispersivity are controlled by soil texture, clay mineralogy and chemistry, strongly influencing the timing and location of runoff and the relative significance of surface and subsurface erosional processes. The absence of shrink-swell cracking of the alluvial surfaces of the pediments indicates a low infiltration capacity and sheetflow. The compact lithology of the sandstone is responsible for its low permeability and high runoff coefficient. Slope drainage of steep sandstone slopes is routed through a deep corrasional pipe network. Silver sagebrush (Artemisia cana) is the only species growing on the popcorn surface of the mudrock, which is in large parts vegetation free. The basal pediment shows a distinct 2 m band surrounding the mudrock outcrop without vegetation as a result of high sedimentation rate due to slope wash. Otherwise the typical pioneer vegetation of this basal pediment are grasses. In the transition zone below the steep sandstone cliffs and above the gentle bentonitic mudrock surfaces patches of short-grass vegetation are found, marking slumped blocks with intact vegetation and soil cover. These patches are surrounded by

  19. Effect of processing on phenolic antioxidants of fruits, vegetables, and grains--a review.

    PubMed

    Nayak, Balunkeswar; Liu, Rui Hai; Tang, Juming

    2015-01-01

    Understanding the influence of processing operations such as drying/dehydration, canning, extrusion, high hydrostatic pressure, pulsed electric field, and ohmic heating on the phytochemicals of fruits, vegetables, and grains is important in retaining the health benefiting properties of these antioxidative compounds in processed food products. Most of the previous investigations in the literature on the antioxidants of fruits, vegetables, and grains have shown that food-processing operations reduced the antioxidants of the processed foods, which is also the usual consumer perception. However, in the last decade some articles in the literature reported that the evaluation of nutritional quality of processed fruits and vegetables not only depend on the quantity of vitamin C but should include analyses of other antioxidant phytochemicals and antioxidant activity. Thermal processing increased the total antioxidant activity of tomato and sweet corn. Most importantly, analysis also depends on the condition, type, and mechanism of antioxidant assays used. This review aims to provide concise information on the influence of various thermal and nonthermal food-processing operations on the stability and kinetics of health beneficial phenolic antioxidants of fruits, vegetables, and grains. PMID:24915381

  20. The Effects of Vegetation Canopy Processes on Snow Surface Energy and Mass Balances

    NASA Astrophysics Data System (ADS)

    Niu, G.; Yang, Z.

    2004-12-01

    This paper addresses the effects of canopy physical processes on snow mass and energy balances in boreal ecosystems. We incorporate new parameterizations of radiation transfer through the vegetation canopy, interception of snow by the vegetation canopy, and under-canopy sensible heat transfer processes into the Versatile Integrator of Surface and Atmosphere (VISA) and test the model results against the Boreal Ecosystem-Atmosphere Study (BOREAS) data observed at South Study Area, Old Jack Pine (SSA-OJP). A modified two-stream radiation transfer scheme that accounts for the three-dimensional (3-D) geometry of vegetation accurately simulates the transferring of solar radiation through the vegetation canopy when the leaf and stem area index (LSAI) is reduced to match the observed, but the simulated wintertime surface albedos are higher than the observed. This overestimation can be removed by lowering the fractional snow cover on the canopy through the introduction of a snow interception model that explicitly describes the loading and unloading of snow and the melting and refreezing of snow. VISA overestimates the downward sensible heat fluxes from the canopy to the snow surface, which leads to earlier snow ablation and a shallower snowpack than the observed. Explicitly including a canopy heat storage term in the canopy energy balance equation decreases the spuriously large amplitude of the diurnal canopy temperature variation and reduces the excessive daytime sensible heat flux from the canopy downward to the snow surface. Sensitivity tests reveal that the turbulent sensible heat flux below the vegetation canopy strongly depends on the canopy absorption coefficient of momentum. During spring, the daytime temperature difference between the snow surface and the vegetation canopy forms a strongly stable atmospheric condition, which results in a larger absorption coefficient of momentum and a weak turbulent sensible heat flux. The modeled excessive downward sensible heat

  1. Effects of vegetation canopy processes on snow surface energy and mass balances

    NASA Astrophysics Data System (ADS)

    Niu, Guo-Yue; Yang, Zong-Liang

    2004-12-01

    This paper addresses the effects of canopy physical processes on snow mass and energy balances in boreal ecosystems. We incorporate new parameterizations of radiation transfer through the vegetation canopy, interception of snow by the vegetation canopy, and under-canopy sensible heat transfer processes into the Versatile Integrator of Surface and Atmosphere (VISA) and test the model results against the Boreal Ecosystem-Atmosphere Study (BOREAS) data observed at South Study Area, Old Jack Pine. A modified two-stream radiation transfer scheme that accounts for the three-dimensional geometry of vegetation accurately simulates the transferring of solar radiation through the vegetation canopy when the leaf and stem area index is reduced to match the observed. VISA produces higher-than-observed surface albedo in wintertime. Implementation of a snow interception model that explicitly describes the loading and unloading of snow and the melting and refreezing of snow on the canopy into VISA reduces the fractional snow cover on the canopy and the surface albedo. VISA overestimates the downward sensible heat fluxes from the canopy to the snow surface, which leads to earlier snow ablation and a shallower snowpack than the observed. Explicitly including a canopy heat storage term in the canopy energy balance equation decreases the spuriously large amplitude of the diurnal canopy temperature variation and reduces the excessive daytime sensible heat flux from the canopy downward to the snow surface. Sensitivity tests reveal that the turbulent sensible heat flux below the vegetation canopy strongly depends on the canopy absorption coefficient of momentum. During spring the daytime temperature difference between the snow surface and the vegetation canopy forms a strongly stable atmospheric condition, which results in a larger absorption coefficient of momentum and a weak turbulent sensible heat flux. The modeled excessive downward sensible heat flux from the vegetation canopy to

  2. Phenopix: a R package to process digital images of a vegetation cover

    NASA Astrophysics Data System (ADS)

    Filippa, Gianluca; Cremonese, Edoardo; Migliavacca, Mirco; Galvagno, Marta; Morra di Cella, Umberto; Richardson, Andrew

    2015-04-01

    Plant phenology is a globally recognized indicator of the effects of climate change on the terrestrial biosphere. Accordingly, new tools to automatically track the seasonal development of a vegetation cover are becoming available and more and more deployed. Among them, near-continuous digital images are being collected in several networks in the US, Europe, Asia and Australia in a range of different ecosystems, including agricultural lands, deciduous and evergreen forests, and grasslands. The growing scientific interest in vegetation image analysis highlights the need of easy to use, flexible and standardized processing techniques. In this contribution we illustrate a new open source package called "phenopix" written in R language that allows to process images of a vegetation cover. The main features include: (i) define of one or more areas of interest on an image and process pixel information within them, (ii) compute vegetation indexes based on red green and blue channels, (iii) fit a curve to the seasonal trajectory of vegetation indexes and extract relevant dates (aka thresholds) on the seasonal trajectory; (iv) analyze image pixels separately to extract spatially explicit phenological information. The utilities of the package will be illustrated in detail for two subalpine sites, a grassland and a larch stand at about 2000 m in the Italian Western Alps. The phenopix package is a cost free and easy-to-use tool that allows to process digital images of a vegetation cover in a standardized, flexible and reproducible way. The software is available for download at the R forge web site (r-forge.r-project.org/projects/phenopix/).

  3. Processes of change for increasing fruit and vegetable consumption among economically disadvantaged African American adolescents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study sought to identify Transtheoretical model processes of change associated with consumption of >=5 daily servings of fruit and vegetables in a sample of economically disadvantaged African American adolescents (N=549; mean (SD) age=12.44 (.99) years; 61% female; 15% African American Hispanic...

  4. A flexible numerical component to simulate surface runoff transport and biogeochemical processes through dense vegetation

    NASA Astrophysics Data System (ADS)

    Munoz-Carpena, R.; Perez-Ovilla, O.

    2012-12-01

    Methods to estimate surface runoff pollutant removal using dense vegetation buffers (i.e. vegetative filter strips) usually consider a limited number of factors (i.e. filter length, slope) and are in general based on empirical relationships. When an empirical approach is used, the application of the model is limited to those conditions of the data used for the regression equations. The objective of this work is to provide a flexible numerical mechanistic tool to simulate dynamics of a wide range of surface runoff pollutants through dense vegetation and their physical, chemical and biological interactions based on equations defined by the user as part of the model inputs. A flexible water quality model based on the Reaction Simulation Engine (RSE) modeling component is coupled to a transport module based on the traditional Bubnov -Galerkin finite element method to solve the advection-dispersion-reaction equation using the alternating split-operator technique. This coupled transport-reaction model is linked to the VFSMOD-W (http://abe.ufl.edu/carpena/vfsmod) program to mechanistically simulate mobile and stabile pollutants through dense vegetation based on user-defined conceptual models (differential equations written in XML language as input files). The key factors to consider in the creation of a conceptual model are the components in the buffer (i.e. vegetation, soil, sediments) and how the pollutant interacts with them. The biogeochemical reaction component was tested successfully with laboratory and field scale experiments. One of the major advantages when using this tool is that the pollutant transport and removal thought dense vegetation is related to physical and biogeochemical process occurring within the filter. This mechanistic approach increases the range of use of the model to a wide range of pollutants and conditions without modification of the core model. The strength of the model relies on the mechanistic approach used for simulating the removal of

  5. Matching ecohydrological processes and scales of banded vegetation patterns in semiarid catchments

    NASA Astrophysics Data System (ADS)

    Paschalis, Athanasios; Katul, Gabriel G.; Fatichi, Simone; Manoli, Gabriele; Molnar, Peter

    2016-03-01

    While the claim that water-carbon interactions result in spatially coherent vegetation patterning is rarely disputed in many arid and semiarid regions, the significance of the detailed water pathways and other high frequency variability remain an open question. How the short temporal scale meteorological fluctuations form the long-term spatial variability of available soil water in complex terrains due to the various hydrological, land surface, and vegetation dynamic feedbacks frames the scope of the work here. Knowledge of the detailed mechanistic feedbacks among soil, plants, and the atmosphere will lead to advances in our understanding of plant water availability in arid and semiarid ecosystems and will provide insights for future model development concerning vegetation pattern formation. In this study, quantitative estimates of water fluxes and vegetation productivity are provided for a semiarid ecosystem with established vegetation bands on hillslopes using numerical simulations. A state-of-the-science process based ecohydrological model is used, which resolves hydrological and plant physiological processes at the relevant space and time scales, for relatively small periods (e.g., decades) of mature ecosystems (i.e., spatially static vegetation distribution). To unfold the mechanisms that shape the spatial distribution of soil moisture, plant productivity and the relevant surface/subsurface and atmospheric water fluxes, idealized hillslope numerical experiments are constructed, where the effects of soil type, slope steepness, and overland flow accumulation area are quantified. Those mechanisms are also simulated in the presence of complex topography features on landscapes. The main results are (a) short temporal scale meteorological variability and accurate representation of the scales at which each ecohydrological process operates are crucial for the estimation of the spatial variability of soil water availability to the plant root zone; (b) water fluxes such

  6. Evaluation of classifiers for processing Hyperion (EO-1) data of tropical vegetation

    NASA Astrophysics Data System (ADS)

    Vyas, Dhaval; Krishnayya, N. S. R.; Manjunath, K. R.; Ray, S. S.; Panigrahy, Sushma

    2011-04-01

    There is an urgent necessity to monitor changes in the natural surface features of earth. Compared to broadband multispectral data, hyperspectral data provides a better option with high spectral resolution. Classification of vegetation with the use of hyperspectral remote sensing generates a classical problem of high dimensional inputs. Complexity gets compounded as we move from airborne hyperspectral to Spaceborne technology. It is unclear how different classification algorithms will perform on a complex scene of tropical forests collected by spaceborne hyperspectral sensor. The present study was carried out to evaluate the performance of three different classifiers (Artificial Neural Network, Spectral Angle Mapper, Support Vector Machine) over highly diverse tropical forest vegetation utilizing hyperspectral (EO-1) data. Appropriate band selection was done by Stepwise Discriminant Analysis. The Stepwise Discriminant Analysis resulted in identifying 22 best bands to discriminate the eight identified tropical vegetation classes. Maximum numbers of bands came from SWIR region. ANN classifier gave highest OAA values of 81% with the help of 22 selected bands from SDA. The image classified with the help SVM showed OAA of 71%, whereas the SAM showed the lowest OAA of 66%. All the three classifiers were also tested to check their efficiency in classifying spectra coming from 165 processed bands. SVM showed highest OAA of 80%. Classified subset images coming from ANN (from 22 bands) and SVM (from 165 bands) are quite similar in showing the distribution of eight vegetation classes. Both the images appeared close to the actual distribution of vegetation seen in the study area. OAA levels obtained in this study by ANN and SVM classifiers identify the suitability of these classifiers for tropical vegetation discrimination.

  7. Application of membrane separation in fruit and vegetable juice processing: a review.

    PubMed

    Ilame, Susmit A; Satyavir, V Singh

    2015-01-01

    Fruit and vegetable juices are used due to convenience. The juices are rich in various minerals, vitamins, and other nutrients. To process the juices and their clarification and/or concentration is required. The membranes are being used for these purposes. These processes are preferred over others because of high efficiency and low temperature. Membranes and their characteristics have been discussed in brief for knowing suitability of membranes for fruit and vegetable juices. Membrane separation is low temperature process in which the organoleptic quality of the juice is almost retained. In this review, different membrane separation methods including Microfiltration, Ultrafiltration, and Reverse osmosis for fruit juices reported in the literature are discussed. The major fruit and vegetable juices using membrane processes are including the Reverse osmosis studies for concentration of Orange juice, Carrot juice, and Grape juice are discusses. The Microfiltration and Ultrafiltration are used for clarification of juices of mosambi juice, apple juice, pineapple juice, and kiwifruit juice. The various optimized parameters in membranes studies are pH, TAA, TSS, and AIS. In this review, in addition to above the OD is also discussed, where the membranes are used. PMID:24915352

  8. Repeat-pass InSAR processing for Vegetation Height Calculation: Theory and a validated example

    NASA Astrophysics Data System (ADS)

    Siqueira, P.; Lei, Y.

    2014-12-01

    million hectare region. The results have been validated using the LVIS lidar system and a map of vegetation height provided by Woods Hole Research Center. This talk will describe the process that was used for creating this map, and how the data processing was automated to account for differences in temporal decorrelation over this large study area.

  9. Effect of grassland vegetation type on the responses of hydrological processes to seasonal precipitation patterns

    NASA Astrophysics Data System (ADS)

    Salve, Rohit; Sudderth, Erika A.; St. Clair, Samuel B.; Torn, Margaret S.

    2011-11-01

    SummaryUnder future climate scenarios, rainfall patterns and species composition in California grasslands are predicted to change, potentially impacting soil-moisture dynamics and ecosystem function. The primary objective of this study was to assess the impact of altered rainfall on soil-moisture dynamics in three annual grassland vegetation types. We monitored seasonal changes in soil moisture under three different rainfall regimes in mesocosms planted with: (1) a mixed forb-grass community, (2) an Avena barbata monoculture, and (3) an Erodium botrys monoculture. We applied watering treatments in pulses, followed by dry periods that are representative of natural rainfall patterns in California annual grasslands. While rainfall was the dominant treatment, its impact on hydrological processes varied over the growing season. Surprisingly, there were only small differences in the hydrologic response among the three vegetation types. We found significant temporal variability in evapotranspiration, seepage, and soil-moisture content. Both Water Use Efficiency (WUE) and Rain Use Efficiency (RUE) decreased as annual precipitation totals increased. Results from this investigation suggest that both precipitation and vegetation have a significant interactive effect on soil-moisture dynamics. When combined, seasonal precipitation and grassland vegetation influence near-surface hydrology in ways that cannot be predicted from manipulation of a single variable.

  10. A mechanistic perspective on process-induced changes in glucosinolate content in Brassica vegetables: a review.

    PubMed

    Nugrahedi, Probo Y; Verkerk, Ruud; Widianarko, Budi; Dekker, Matthijs

    2015-01-01

    Brassica vegetables are consumed mostly after processing, which is expected to give beneficial effects on the vegetable properties, such as improved palatability and bioavailability of nutrients, or shelf life extension. But processing also results to various changes in the content of health promoting phytochemicals like glucosinolates. This paper reviews the effects of processing on the glucosinolates content by using a mechanism approach underlying processing method employed. Cultural differences between Eastern and Western preparation practices and their possible effect on glucosinolate retention are highlighted. Boiling and blanching considerably reduce the glucosinolate content mainly due to mechanisms of cell lysis, diffusion, and leaching, and partly due to thermal and enzymatic degradation. Steaming, microwave processing, and stir frying either retain or slightly reduce the glucosinolates content due to low degrees of leaching; moreover, these methods seem to enhance extractability of glucosinolates from the plant tissue. Fermentation reduces the glucosinolate content considerably, but the underlying mechanisms are not yet studied in detail. Studying the changes of glucosinolates during processing by a mechanistic approach is shown to be valuable to understand the impact of processing and to optimize processing conditions for health benefits of these compounds. PMID:24915330

  11. Effect of the food production chain from farm practices to vegetable processing on outbreak incidence.

    PubMed

    Jung, Yangjin; Jang, Hyein; Matthews, Karl R

    2014-11-01

    The popularity in the consumption of fresh and fresh-cut vegetables continues to increase globally. Fresh vegetables are an integral part of a healthy diet, providing vitamins, minerals, antioxidants and other health-promoting compounds. The diversity of fresh vegetables and packaging formats (spring mix in clamshell container, bagged heads of lettuce) support increased consumption. Unfortunately, vegetable production and processing practices are not sufficient to ensure complete microbial safety. This review highlights a few specific areas that require greater attention and research. Selected outbreaks are presented to emphasize the need for science-based 'best practices'. Laboratory and field studies have focused on inactivation of pathogens associated with manure in liquid, slurry or solid forms. As production practices change, other forms and types of soil amendments are being used more prevalently. Information regarding the microbial safety of fish emulsion and pellet form of manure is limited. The topic of global climate change is controversial, but the potential effect on agriculture cannot be ignored. Changes in temperature, precipitation, humidity and wind can impact crops and the microorganisms that are associated with production environments. Climate change could potentially enhance the ability of pathogens to survive and persist in soil, water and crops, increasing human health risks. Limited research has focused on the prevalence and behaviour of viruses in pre and post-harvest environments and on vegetable commodities. Globally, viruses are a major cause of foodborne illnesses, but are seldom tested for in soil, soil amendments, manure and crops. Greater attention must also be given to the improvement in the microbial quality of seeds used in sprout production. Human pathogens associated with seeds can result in contamination of sprouts intended for human consumption, even when all appropriate 'best practices' are used by sprout growers. PMID:25251466

  12. Effect of the food production chain from farm practices to vegetable processing on outbreak incidence

    PubMed Central

    Jung, Yangjin; Jang, Hyein; Matthews, Karl R

    2014-01-01

    The popularity in the consumption of fresh and fresh-cut vegetables continues to increase globally. Fresh vegetables are an integral part of a healthy diet, providing vitamins, minerals, antioxidants and other health-promoting compounds. The diversity of fresh vegetables and packaging formats (spring mix in clamshell container, bagged heads of lettuce) support increased consumption. Unfortunately, vegetable production and processing practices are not sufficient to ensure complete microbial safety. This review highlights a few specific areas that require greater attention and research. Selected outbreaks are presented to emphasize the need for science-based ‘best practices’. Laboratory and field studies have focused on inactivation of pathogens associated with manure in liquid, slurry or solid forms. As production practices change, other forms and types of soil amendments are being used more prevalently. Information regarding the microbial safety of fish emulsion and pellet form of manure is limited. The topic of global climate change is controversial, but the potential effect on agriculture cannot be ignored. Changes in temperature, precipitation, humidity and wind can impact crops and the microorganisms that are associated with production environments. Climate change could potentially enhance the ability of pathogens to survive and persist in soil, water and crops, increasing human health risks. Limited research has focused on the prevalence and behaviour of viruses in pre and post-harvest environments and on vegetable commodities. Globally, viruses are a major cause of foodborne illnesses, but are seldom tested for in soil, soil amendments, manure and crops. Greater attention must also be given to the improvement in the microbial quality of seeds used in sprout production. Human pathogens associated with seeds can result in contamination of sprouts intended for human consumption, even when all appropriate ‘best practices’ are used by sprout growers. PMID

  13. Influence of High-Pressure Processing on the Profile of Polyglutamyl 5-Methyltetrahydrofolate in Selected Vegetables

    PubMed Central

    Wang, Chao; Riedl, Ken M.; Somerville, Jeremy; Balasubramaniam, V. M.; Schwartz, Steven J.

    2013-01-01

    In plants, folate occurs predominantly as 5-methyltetrahydrofolate (5MTHF) polyglutamyl forms. Differences in stability and bioavailability of food folate compared to synthetic folic acid have been attributed to the presence of the polyglutamyl chain. High-pressure processing (HPP) was tested for whether it might shorten polyglutamyl chains of 5MTHF species in fresh vegetables by enabling action of native γ-glutamylhydrolase (GGH). A validated ultrahigh-performance reversed-phase liquid chromatography–tandem mass spectrometry method using stable isotope as internal standard was applied for characterizing 5MTHF polyglutamyl profiles. HPP conditions included 300, 450, and 600 MPa at 30 °C for 0 or 5 min, and vegetables were vacuum-packed before treatment. Investigated vegetables included cauliflower (Brassica oleracea), baby carrots (Daucus carota), and carrot greens (D. carota). HPP treatment caused conversion of polyglutamyl 5MTHF species to short-chain and monoglutamyl forms. Maximal conversion of polyglutamyl folate to monoglutamyl folate occurred at the highest pressure/time combination investigated, 600 MPa/30 °C/5 min. Under this condition, cauliflower monoglutamyl folate increased nearly 4-fold, diglutamyl folate 32-fold, and triglutamyl folate 8-fold; carrot monoglutamyl increased 23-fold and diglutamyl 32-fold; and carrot greens monoglutamyl increased 2.5-fold and the diglutamyl form 19-fold. Although some folate degradation was observed at certain intermediate HPP conditions, total 5MTHF folate was largely preserved at 600 MPa/5 min. Thus, HPP of raw vegetables is a feasible strategy for enhancing vegetable monoglutamate 5MTHF. PMID:21770413

  14. [Examination of processed vegetable foods for the presence of common DNA sequences of genetically modified tomatoes].

    PubMed

    Kitagawa, Mamiko; Nakamura, Kosuke; Kondo, Kazunari; Ubukata, Shoji; Akiyama, Hiroshi

    2014-01-01

    The contamination of processed vegetable foods with genetically modified tomatoes was investigated by the use of qualitative PCR methods to detect the cauliflower mosaic virus 35S promoter (P35S) and the kanamycin resistance gene (NPTII). DNA fragments of P35S and NPTII were detected in vegetable juice samples, possibly due to contamination with the genomes of cauliflower mosaic virus infecting juice ingredients of Brassica species and soil bacteria, respectively. Therefore, to detect the transformation construct sequences of GM tomatoes, primer pairs were designed for qualitative PCR to specifically detect the border region between P35S and NPTII, and the border region between nopaline synthase gene promoter and NPTII. No amplification of the targeted sequences was observed using genomic DNA purified from the juice ingredients. The developed qualitative PCR method is considered to be a reliable tool to check contamination of products with GM tomatoes. PMID:25743587

  15. Microbial Evaluation of Fresh, Minimally-processed Vegetables and Bagged Sprouts from Chain Supermarkets

    PubMed Central

    Jeddi, Maryam Zare; Yunesian, Masud; Gorji, Mohamad Es'haghi; Noori, Negin; Pourmand, Mohammad Reza

    2014-01-01

    ABSTRACT The aim of this study was to evaluate the bacterial and fungal quality of minimally-processed vegetables (MPV) and sprouts. A total of 116 samples of fresh-cut vegetables, ready-to-eat salads, and mung bean and wheat sprouts were randomly collected and analyzed. The load of aerobic mesophilic bacteria was minimum and maximum in the fresh-cut vegetables and fresh mung bean sprouts respectively, corresponding to populations of 5.3 and 8.5 log CFU/g. E. coli O157:H7 was found to be absent in all samples; however,  other E. coli strains were detected in 21 samples (18.1%), and Salmonella spp. were found in one mung bean (3.1%) and one ready-to-eat salad sample (5%). Yeasts were the predominant organisms and were found in 100% of the samples. Geotrichum, Fusarium, and Penicillium spp. were the most prevalent molds in mung sprouts while Cladosporium and Penicillium spp. were most frequently found in ready-to-eat salad samples. According to results from the present study, effective control measures should be implemented to minimize the microbiological contamination of fresh produce sold in Tehran, Iran. PMID:25395902

  16. Antimicrobial edible films and coatings for fresh and minimally processed fruits and vegetables: a review.

    PubMed

    Valencia-Chamorro, Silvia A; Palou, Lluís; Del Río, Miguel A; Pérez-Gago, María B

    2011-01-01

    The use of edible films and coatings is an environmentally friendly technology that offers substantial advantages for shelf-life increase of many food products including fruits and vegetables. The development of new natural edible films and coatings with the addition of antimicrobial compounds to preserve fresh and minimally processed fruits and vegetables is a technological challenge for the industry and a very active research field worldwide. Antimicrobial agents have been successfully added to edible composite films and coatings based on polysaccharides or proteins such as starch, cellulose derivatives, chitosan, alginate, fruit puree, whey protein isolated, soy protein, egg albumen, wheat gluten, or sodium caseinate. This paper reviews the development of edible films and coatings with antimicrobial activity, typically through the incorporation of antimicrobial food additives as ingredients, the effect of these edible films on the control of target microorganisms, the influence of antimicrobial agents on mechanical and barrier properties of stand-alone edible films, and the effect of the application of antimicrobial edible coatings on the quality of fresh and fresh-cut fruits and vegetables. PMID:21888536

  17. [Influence of thermal processing and storage on the content of nitrates and nitrites in chosen vegetables from the Podlasie province].

    PubMed

    Roszczenko, A; Rogalska, J; Potapczuk, L; Kleczyńska, A

    2001-01-01

    The dangerous for health nitrate and nitrite can penetrate with food human organism for this reason in study the influence of thermal processing and storage on the level of these compounds in the vegetables was determined. The content of nitrates and nitrites was determined in such vegetables as carrot, parsley-root, celery and potatoes growing by farmers in the Podlasie province. Nitrates and nitrites were assessed in fresh and boiled vegetables as well as in the stock and in carrot juice. These compounds were also determined after storage of vegetables at +4 degrees C for 2 weeks and at -15 degrees C for 1 and 3 months. Nitrates and nitrites concentrations were assayed colorimetrically by the Griess method modified to food investigation. Boiling reduced nitrate content in the vegetables. Considerable part (about 50%) of these compounds passed into stock during boiling. Storage of these vegetables at +4 degrees C resulted in slight lowering of nitrate content in carrot and parsley-root and marked elevation in celery. Cold storage of vegetables through 1 and 3 months had no important influence on nitrate content. Boiling decreased the content of nitrites similarly as nitrates. Storage of the vegetables at +4 degrees C through 2 weeks led to an increase in nitrite content in carrot and parsley-root while in celery the content of nitrites was reduced. Storage of vegetables at -15 degrees C resulted in lowering content of nitrite. The study revealed that the vegetable-roots (carrot, parsley and celery) and potatoes cultivated in the Podlasie province as well as in the other provinces were excessively contaminated by nitrates and nitrites. Moreover, it has been shown that thermal processing such as boiling considerably reduced the content of nitrates and nitrites in these vegetables while freezing changed mainly nitrite content. PMID:11957780

  18. Preserved feedforward but impaired top-down processes in the vegetative state.

    PubMed

    Boly, Melanie; Garrido, Marta Isabel; Gosseries, Olivia; Bruno, Marie-Aurélie; Boveroux, Pierre; Schnakers, Caroline; Massimini, Marcello; Litvak, Vladimir; Laureys, Steven; Friston, Karl

    2011-05-13

    Frontoparietal cortex is involved in the explicit processing (awareness) of stimuli. Frontoparietal activation has also been found in studies of subliminal stimulus processing. We hypothesized that an impairment of top-down processes, involved in recurrent neuronal message-passing and the generation of long-latency electrophysiological responses, might provide a more reliable correlate of consciousness in severely brain-damaged patients, than frontoparietal responses. We measured effective connectivity during a mismatch negativity paradigm and found that the only significant difference between patients in a vegetative state and controls was an impairment of backward connectivity from frontal to temporal cortices. This result emphasizes the importance of top-down projections in recurrent processing that involve high-order associative cortices for conscious perception. PMID:21566197

  19. Inventories of Delaware's coastal vegetation and land-use utilizing digital processing of ERTS-1 imagery

    NASA Technical Reports Server (NTRS)

    Klemas, V. (Principal Investigator); Bartlett, D.; Rogers, R.; Reed, L.

    1974-01-01

    The author has identified the following significant results. Analysis of ERTS-1 color composite images using analogy processing equipment confirmed that all the major wetlands plant species were distinguishable at ERTS-1 scale. Furthermore, human alterations of the coastal zone were easily recognized since such alterations typically involve removal of vegetative cover resulting in a change of spectral signature. The superior spectral resolution of the CCTs as compared with single band or composite imagery has indeed provided good discrimination through digital analysis of the CCTs with the added advantage of rapid production of thematic maps and data.

  20. Prevalence and level of Listeria monocytogenes and other Listeria sp. in ready-to-eat minimally processed and refrigerated vegetables.

    PubMed

    Kovačević, Mira; Burazin, Jelena; Pavlović, Hrvoje; Kopjar, Mirela; Piližota, Vlasta

    2013-04-01

    Minimally processed and refrigerated vegetables can be contaminated with Listeria species bacteria including Listeria monocytogenes due to extensive handling during processing or by cross contamination from the processing environment. The objective of this study was to examine the microbiological quality of ready-to-eat minimally processed and refrigerated vegetables from supermarkets in Osijek, Croatia. 100 samples of ready-to-eat vegetables collected from different supermarkets in Osijek, Croatia, were analyzed for presence of Listeria species and Listeria monocytogenes. The collected samples were cut iceberg lettuces (24 samples), other leafy vegetables (11 samples), delicatessen salads (23 samples), cabbage salads (19 samples), salads from mixed (17 samples) and root vegetables (6 samples). Listeria species was found in 20 samples (20 %) and Listeria monocytogenes was detected in only 1 sample (1 %) of cut red cabbage (less than 100 CFU/g). According to Croatian and EU microbiological criteria these results are satisfactory. However, the presence of Listeria species and Listeria monocytogenes indicates poor hygiene quality. The study showed that these products are often improperly labeled, since 24 % of analyzed samples lacked information about shelf life, and 60 % of samples lacked information about storage conditions. With regard to these facts, cold chain abruption with extended use after expiration date is a probable scenario. Therefore, the microbiological risk for consumers of ready-to-eat minimally processed and refrigerated vegetables is not completely eliminated. PMID:23225207

  1. Integrated microwave processing system for the extraction of organophosphorus pesticides in fresh vegetables.

    PubMed

    Wu, Lijie; Song, Ying; Hu, Mingzhu; Xu, Xu; Zhang, Hanqi; Yu, Aimin; Ma, Qiang; Wang, Ziming

    2015-03-01

    A simple and efficient integrated microwave processing system (IMPS) was firstly assembled and validated for the extraction of organophosphorus pesticides in fresh vegetables. Two processes under microwave irradiation, dynamic microwave-assisted extraction (DMAE) and microwave-accelerated solvent elution (MASE), were integrated for simplifying the pretreatment of the sample. Extraction, separation, enrichment and elution were finished in a simple step. The organophosphorus pesticides were extracted from the fresh vegetables into hexane with DMAE, and then the extract was directly introduced into the enrichment column packed with active carbon fiber (ACF). Subsequently, the organophosphorus pesticides trapped on the ACF were eluted with ethyl acetate under microwave irradiation. No further filtration or cleanup was required before analysis of the eluate by gas chromatography-mass spectrometry. Some experimental parameters affecting extraction efficiency were investigated and optimized, such as microwave output power, kind and volume of extraction solvent, extraction time, amount of sorbent, elution microwave power, kind and volume of elution solvent, elution solvent flow rate. Under the optimized conditions, the recoveries were in the range of 71.5-105.2%, and the relative standard deviations were lower than 11.6%. The experiment results prove that the present method is a simple and effective sample preparation method for the determination of pesticides in solid samples. PMID:25618681

  2. Feedbacks between vegetation and solifluction processes on hillslopes: a case study of an alpine turf-banked solifluction lobe

    NASA Astrophysics Data System (ADS)

    Eichel, Jana; Draebing, Daniel; Wieland, Markus; Eling, Christian; Klingbeil, Lasse; Dikau, Richard

    2015-04-01

    Solifluction is one of the most widespread processes transporting soil on hillslopes in periglacial environments. While periglacial geomorphologists identified climatic and soil parameters as most important factors influencing solifluction, ecologist have long recognized the importance of vegetation and the co-occurrence of certain species and vegetation communities with solifluction processes and landforms. However, the mechanism of vegetation influences on solifluction, as well as feedbacks between solifluction processes and vegetation, which result in specific vegetation organization and specific landforms, e.g., turf-banked solifluction lobes, is only partly understood. The aim of our study is to improve the understanding of feedbacks between vegetation and solifluction processes and landforms by using established and up-to-date methods in a detailed small-scale study on a turf-banked solifluction lobe in the Turtmann glacier forefield (Switzerland). Our objectives are (i) to examine the effects of species composition and vegetation organization on landform properties; (ii) to investigate the effects of landform properties on species composition and vegetation organization and (iii) to evaluate if feedbacks create turf-banked solifluction lobes as biogeomorphic structures. To assess solifluction lobe and vegetation properties, we employed a detailed geomorphic and vegetation mapping (1:50), complemented by an UAV derived high-resolution orthophoto and DEM, and 2D and 3D electrical resistivity tomography (ERT) measurements in combination with soil moisture measurements. Vegetation mapping shows that (i) dwarf shrubs, which through their plant functional traits can act as engineer species, are the main species covering the solifluction lobe. Geomorphic mapping, DEM terrain analyses and 3D ERT indicate that (ii) lobe geomorphometry and material properties (grain size, moisture) strongly influence species distribution and diversity. 2D ERT shows permafrost

  3. Changing vegetation self organisation affecting eco-hydrological and geomorphological processes under invasion of blue bush in SE South Africa

    NASA Astrophysics Data System (ADS)

    Cammeraat, L. H.; Kakembo, V.

    2012-04-01

    In southeastern South Africa sub-humid grasslands on abandoned soils are spontaneously being invaded by the exotic shrub Pteronia incana (Blue bush) originating from the semi-arid and arid Karoo region. This results eventually in soil loss and rill and gully erosion and consequently loss in agricultural production affecting the local rural economy. Degradation of soils is occurring following replacement of grassland by unpalatable shrubs and altering the spatial organization of the vegetation. This in consequence is changing the eco-hydrological response of the hillslopes leading to a dramatic increase of runoff and erosion. However the reason for this spontaneous vegetation replacement is not clear. Various explanations have been proposed and discussed such as overgrazing, vegetation cover and rainfall, drought or climatic change or exposition. The study presented aims at quantifying the observed changes in the plant and bare spot patterns and which may help us unraveling vegetation self organisation processes in relation to environmental disturbances. We analyzed high resolution low altitude images of vegetation patterns in combination with high resolution digital terrain model analysis. We applied this procedure for different patterns reflecting a time series covering the observed changing patterns. These reflect changing interactions between the (re-) organization of the plant patterns during the bushy invasion and incorporated the interaction between vegetation, water redistribution and soil properties. By doing so we may be able to unravel critical processes as indicated by changes in vegetation patterns that might enable us to mitigate degradation of dryland ecosystems.

  4. Optimization of cow dung spiked pre-consumer processing vegetable waste for vermicomposting using Eisenia fetida.

    PubMed

    Garg, V K; Gupta, Renuka

    2011-01-01

    This paper reports the optimization of cow dung (CD) spiked pre-consumer processing vegetable waste (PPVW) for vermicomposting using Eisenia fetida in a laboratory scale study. Vermicomposting process decreased carbon and organic matter concentration and increased N, P and K content in the vermicompost. The C:N ratio was decreased by 45-69% in different vermireactors indicating stabilization of the waste. The heavy metal content was within permissible limits of their application in agricultural soils. It has been concluded from the results that addition of PPVW up to 40% with CD can produce a good quality vermicompost. Whereas, growth and fecundity of E. fetida was best when reared in 20% PPVW+80% CD feed mixture. However, higher percentages of PPVW in different vermireactors significantly affected the growth and fecundity of worms. PMID:20951432

  5. The effect of vegetation biophysical processes (VBP) on the American monsoon

    NASA Astrophysics Data System (ADS)

    Xue, Y.; de Sales, F.; Mechoso, C. R.; Vasic, R.; Nobre, C.

    2006-12-01

    Although the role of individual land surface characteristics, such as soil moisture and albedo, in the climate system has been widely recognized, the effects of vegetation biophysical processes (VBP) are not yet fully understood. The Simplified Simple Biosphere Model (SSiB) has been coupled to the atmospheric general circulation models to investigate the role and mechanism of land/American monsoon interactions. Two numerical experiments have been designed for this study. In the first experiment, two land surface parameterizations in the UCLA GCM were tested: one used the standard version of the UCLA GCM land surface parameterization (CNTL), which used climatological surface albedo and specified ground wetness, i.e. no land/atmosphere interaction was allowed; another used SSiB with an explicit representation of VBP. The UCLA/SSiB showed a substantial impact on the American monsoon. The systematic bias in the American monsoon precipitation in the CNTL simulation was reduced. The annual mean precipitation bias was reduced by 50%. The improvement was consistent for all monsoon months. Furthermore, the interaction between VBP and Inter-Tropical Convergence Zone (ITCZ) was evident. To further distinguish the VBP effect from the soil moisture effect, the second experiment was designed. In this experiment, two land surface parameterizations were tested: one was a surface model with two-soil layers (SOIL), i.e., soil moisture interacted with atmosphere, with no explicit vegetation parameterizations and another was SSiB. The results showed that, during the austral summer, consideration of explicit vegetation processes did not alter the monthly mean precipitation at the planetary scale. However, at continental scales, GCM/SSiB produces a more successful simulation of South American monsoon system (SAMS) than GCM/Soil. The improvement was particularly clear in reference to the seasonal southward displacement of precipitation during the onset of SAMS and its northward merging

  6. Role of submerged vegetation in the retention processes of three plant protection products in flow-through stream mesocosms.

    PubMed

    Stang, Christoph; Wieczorek, Matthias Valentin; Noss, Christian; Lorke, Andreas; Scherr, Frank; Goerlitz, Gerhard; Schulz, Ralf

    2014-07-01

    Quantitative information on the processes leading to the retention of plant protection products (PPPs) in surface waters is not available, particularly for flow-through systems. The influence of aquatic vegetation on the hydraulic- and sorption-mediated mitigation processes of three PPPs (triflumuron, pencycuron, and penflufen; logKOW 3.3-4.9) in 45-m slow-flowing stream mesocosms was investigated. Peak reductions were 35-38% in an unvegetated stream mesocosm, 60-62% in a sparsely vegetated stream mesocosm (13% coverage with Elodea nuttallii), and in a similar range of 57-69% in a densely vegetated stream mesocosm (100% coverage). Between 89% and 93% of the measured total peak reductions in the sparsely vegetated stream can be explained by an increase of vegetation-induced dispersion (estimated with the one-dimensional solute transport model OTIS), while 7-11% of the peak reduction can be attributed to sorption processes. However, dispersion contributed only 59-71% of the peak reductions in the densely vegetated stream mesocosm, where 29% to 41% of the total peak reductions can be attributed to sorption processes. In the densely vegetated stream, 8-27% of the applied PPPs, depending on the logKOW values of the compounds, were temporarily retained by macrophytes. Increasing PPP recoveries in the aqueous phase were accompanied by a decrease of PPP concentrations in macrophytes indicating kinetic desorption over time. This is the first study to provide quantitative data on how the interaction of dispersion and sorption, driven by aquatic macrophytes, influences the mitigation of PPP concentrations in flowing vegetated stream systems. PMID:24875866

  7. What Constitutes a Fruit or Vegetable Serving Equivalent in Processed Products?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    WHO and FAO are part of a global initiative to promote consumption of fruits and vegetables, stating that low fruit and vegetable intake is a key risk factor for obesity, heart disease, and cancer, accounting at least 2.7 million deaths a year to insufficient fruit and vegetable intake. The Preside...

  8. Agricultural recycling of treatment-plant sludge: a case study for a vegetable-processing factory.

    PubMed

    Dolgen, Deniz; Alpaslan, M Necdet; Delen, Nafiz

    2007-08-01

    The present study evaluated the possibility of using the sludge produced by a vegetable-processing factory in agriculture. The sludge was amended with a soil mixture (i.e., a mixture of sand, soil, and manure) and was applied at 0, 165, 330, 495 and 660 t/ha to promote the growth of cucumbers. The effects of various sludge loadings on plant growth were assessed by counting plants and leaves, measuring stem lengths, and weighing the green parts and roots of the plants. We also compared heavy metal uptake by the plants for sludge loadings of 330, 495, and 660 t/ha with various recommended standards for vegetables. Our results showed that plant growth patterns were influenced to some extent by the sludge loadings. In general, the number of leaves, stem length, and dry weight of green parts exhibited a pronounced positive growth response compared with an unfertilized control, and root growth showed a lesser but still significant response at sludge loadings of 165 and 330 t/ha. The sludge application caused no significant increase in heavy metal concentrations in the leaves, though zinc (Zn) and iron (Fe) were found at elevated concentrations. However, despite the Zn and Fe accumulation, we observed no toxicity symptoms in the plants. This may be a result of cucumber's tolerance of high metal levels. PMID:16934389

  9. Mapping forest vegetation with ERTS-1 MSS data and automatic data processing techniques

    NASA Technical Reports Server (NTRS)

    Messmore, J.; Copeland, G. E.; Levy, G. F.

    1975-01-01

    This study was undertaken with the intent of elucidating the forest mapping capabilities of ERTS-1 MSS data when analyzed with the aid of LARS' automatic data processing techniques. The site for this investigation was the Great Dismal Swamp, a 210,000 acre wilderness area located on the Middle Atlantic coastal plain. Due to inadequate ground truth information on the distribution of vegetation within the swamp, an unsupervised classification scheme was utilized. Initially pictureprints, resembling low resolution photographs, were generated in each of the four ERTS-1 channels. Data found within rectangular training fields was then clustered into 13 spectral groups and defined statistically. Using a maximum likelihood classification scheme, the unknown data points were subsequently classified into one of the designated training classes. Training field data was classified with a high degree of accuracy (greater than 95%), and progress is being made towards identifying the mapped spectral classes.

  10. Mapping forest vegetation with ERTS-1 MSS data and automatic data processing techniques

    NASA Technical Reports Server (NTRS)

    Messmore, J.; Copeland, G. E.; Levy, G. F.

    1975-01-01

    This study was undertaken with the intent of elucidating the forest mapping capabilities of ERTS-1 MSS data when analyzed with the aid of LARS' automatic data processing techniques. The site for this investigation was the Great Dismal Swamp, a 210,000 acre wilderness area located on the Middle Atlantic coastal plain. Due to inadequate ground truth information on the distribution of vegetation within the swamp, an unsupervised classification scheme was utilized. Initially pictureprints, resembling low resolution photographs, were generated in each of the four ERTS-1 channels. Data found within rectangular training fields was then clustered into 13 spectral groups and defined statistically. Using a maximum likelihood classification scheme, the unknown data points were subsequently classified into one of the designated training classes. Training field data was classified with a high degree of accuracy (greater than 95 percent), and progress is being made towards identifying the mapped spectral classes.

  11. Production of acetic acid by hydrothermal two-step process of vegetable wastes for use as a road deicer

    NASA Astrophysics Data System (ADS)

    Jin, F.; Watanabe, Y.; Kishita, A.; Enomoto, H.; Kishida, H.

    2008-07-01

    This study aimed to produce acetic acid from vegetable wastes by a new hydrothermal two-step process. A continuous flow reaction system with a maximum treatment capacity of 2 kg/h of dry biomass developed by us was used. Five kinds of vegetables of carrots, white radish, chinese cabbage, cabbage and potato were selected as the representation of vegetable wastes. First, batch experiments with the selected vegetables were performed under the condition of 300°C, 1 min for the first step, and 300°C, 1 min and 70% oxygen supply for the second step, which is the optimum condition for producing acetic acid in the case of using starch as test material. The highest yields of acetic acid from five vegetables were almost the same as those obtained from starch. Subsequently, similar the highest yield of acetic acid and experimental conditions from vegetables were also obtained successfully using the continuous flow reaction system. These results should be useful for developing an industrial scale process.

  12. An intermediate process-based fire parameterization in Dynamic Global Vegetation Model

    NASA Astrophysics Data System (ADS)

    Li, F.; Zeng, X.

    2011-12-01

    An intermediate process-based fire parameterization has been developed for global fire simulation. It fits the framework of Dynamic Global Vegetation Model (DGVM) which has been a pivot component in Earth System Model (ESM). The fire parameterization comprises three parts: fire occurrence, fire spread, and fire impact. In the first part, the number of fires is determined by ignition counts due to anthropogenic and natural causes and three constraints: fuel load, fuel moisture, and human suppression. Human caused ignition and suppression is explicitly considered as a nonlinear function of population density. The fire counts rather than fire occurrence probability is estimated to avoid underestimating the observed high burned area fraction in tropical savannas where fire occurs frequently. In the second part, post-fire region is assumed to be elliptical in shape with the wind direction along the major axis and the point of ignition at one of the foci. Burned area is determined by fire spread rate,fire duration, and fire counts. Mathematical characteristics of ellipse and some mathematical derivations are used to avoid redundant and unreasonable equations and assumptions in the CTEM-FIRE and make the parameterization equations self-consistently. In the third part, the impact of fire on vegetation component and structure, carbon cycle, trace gases and aerosol emissions are taken into account. The new estimates of trace gas and aerosol emissions due to biomass burning offers an interface with aerosol and atmospheric chemistry model in ESMs. Furthermore, in the new fire parameterization, fire occurrence part and fire spread part can be updated hourly or daily, and fire impact part can be updated daily, monthly, or annually. Its flexibility in selection of time-step length makes it easily applied to various DGVMs. The improved Community Land Model 3.0's Dynamic Global Vegetation Model (CLM-DGVM) is used as the model platform to assess the global performance of the new

  13. Overcoming issues associated with the scale-up of a continuous flow microwave system for aseptic processing of vegetable purees

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Continuous flow microwave heating is a promising alternative to conventional heating for aseptic processing of low-acid vegetable purees. However, non-uniform temperature distribution and control of processing parameters are the major hurdles in the implementation of continuous flow microwave heatin...

  14. Relationship Between Remotely-sensed Vegetation Indices, Canopy Attributes and Plant Physiological Processes: What Vegetation Indices Can and Cannot Tell Us About the Landscape

    PubMed Central

    Glenn, Edward P.; Huete, Alfredo R.; Nagler, Pamela L.; Nelson, Stephen G.

    2008-01-01

    Vegetation indices (VIs) are among the oldest tools in remote sensing studies. Although many variations exist, most of them ratio the reflection of light in the red and NIR sections of the spectrum to separate the landscape into water, soil, and vegetation. Theoretical analyses and field studies have shown that VIs are near-linearly related to photosynthetically active radiation absorbed by a plant canopy, and therefore to light-dependent physiological processes, such as photosynthesis, occurring in the upper canopy. Practical studies have used time-series VIs to measure primary production and evapotranspiration, but these are limited in accuracy to that of the data used in ground truthing or calibrating the models used. VIs are also used to estimate a wide variety of other canopy attributes that are used in Soil-Vegetation-Atmosphere Transfer (SVAT), Surface Energy Balance (SEB), and Global Climate Models (GCM). These attributes include fractional vegetation cover, leaf area index, roughness lengths for turbulent transfer, emissivity and albedo. However, VIs often exhibit only moderate, non-linear relationships to these canopy attributes, compromising the accuracy of the models. We use case studies to illustrate the use and misuse of VIs, and argue for using VIs most simply as a measurement of canopy light absorption rather than as a surrogate for detailed features of canopy architecture. Used this way, VIs are compatible with “Big Leaf” SVAT and GCMs that assume that canopy carbon and moisture fluxes have the same relative response to the environment as any single leaf, simplifying the task of modeling complex landscapes.

  15. Improved simulation of fire-vegetation interactions in the Land surface Processes and eXchanges dynamic global vegetation model (LPX-Mv1)

    NASA Astrophysics Data System (ADS)

    Kelley, D. I.; Harrison, S. P.; Prentice, I. C.

    2014-10-01

    The Land surface Processes and eXchanges (LPX) model is a fire-enabled dynamic global vegetation model that performs well globally but has problems representing fire regimes and vegetative mix in savannas. Here we focus on improving the fire module. To improve the representation of ignitions, we introduced a reatment of lightning that allows the fraction of ground strikes to vary spatially and seasonally, realistically partitions strike distribution between wet and dry days, and varies the number of dry days with strikes. Fuel availability and moisture content were improved by implementing decomposition rates specific to individual plant functional types and litter classes, and litter drying rates driven by atmospheric water content. To improve water extraction by grasses, we use realistic plant-specific treatments of deep roots. To improve fire responses, we introduced adaptive bark thickness and post-fire resprouting for tropical and temperate broadleaf trees. All improvements are based on extensive analyses of relevant observational data sets. We test model performance for Australia, first evaluating parameterisations separately and then measuring overall behaviour against standard benchmarks. Changes to the lightning parameterisation produce a more realistic simulation of fires in southeastern and central Australia. Implementation of PFT-specific decomposition rates enhances performance in central Australia. Changes in fuel drying improve fire in northern Australia, while changes in rooting depth produce a more realistic simulation of fuel availability and structure in central and northern Australia. The introduction of adaptive bark thickness and resprouting produces more realistic fire regimes in Australian savannas. We also show that the model simulates biomass recovery rates consistent with observations from several different regions of the world characterised by resprouting vegetation. The new model (LPX-Mv1) produces an improved simulation of observed

  16. Effects of Freeze-Dried Vegetable Products on the Technological Process and the Quality of Dry Fermented Sausages.

    PubMed

    Eisinaite, Viktorija; Vinauskiene, Rimante; Viskelis, Pranas; Leskauskaite, Daiva

    2016-09-01

    The aim of this study was to compare the chemical composition of freeze-dried vegetable powders: celery, celery juice, parsnip and leek. The effect of different freeze-dried vegetables onto the ripening process and the properties of dry fermented sausages was also evaluated. Vegetable products significantly (p < 0.05) differed in their chemical composition: celery products contained higher amounts of nitrates, total phenolic compounds and lower amounts of sucrose, parsnip had higher concentration of proteins, leek was rich in fat. The analysis of pH, water activity, lactic acid bacteria, coagulase-positive staphylococci and coliforms content showed that the incorporation of freeze-dried vegetables had no negative effect on the fermentation and ripening process of dry fermented sausages. In addition, the color parameters for sausages with the added lyophilised celery products were considerable (p < 0.05) more stable during these processes. At the end of the ripening process the sausages made with lyophilised celery juice were characterised by higher lightness and lower hardness than those made with the addition of other vegetable products and control. Freeze-dried celery, celery juice, parsnip and leek have some potential for the usage as a functional ingredient or as a source for indirect addition of nitrate in the production of fermented sausages. PMID:27526658

  17. Information Processes Mediate the Effect of a Health Communication Intervention on Fruit and Vegetable Consumption

    PubMed Central

    Ko, Linda K.; Campbell, Marci K.; Lewis, Megan A.; Earp, Jo Anne; DeVellis, Brenda

    2016-01-01

    Health communication interventions have been effective in promoting fruit and vegetable consumption (FVC). To explore mechanisms underlying health communication effectiveness, we investigated whether information processes mediated the relationship between health communication and FVC, using data from NC STRIDES. NC STRIDES tested the efficacy of two health communication strategies to promote FVC among a diverse population-based sample of older adults. Participants were randomized to one of four groups: control, tailored print communication (TPC), telephone motivational interviewing (TMI), or combined (TPC+TMI). Multi-sample structural equation models were constructed to analyze data from 469 participants. Information processes mediated the effect of TMI and TPC+TMI on FVC. TMI had an indirect effect on FVC through relevance of the communications. TPC+TMI influenced FVC through perceived relevance of the communications, trust in the communications, and dose recall via two paths. In the first path, relevance was associated with trust. Trust was associated with recall, and greater recall predicted FVC. In the second path, relevance was associated with dose recall, and more recall predicted FVC. Thus, we found that key information processes mediated the relationship between a health communication intervention and FVC. Further research should investigate ways to enhance relevance, trust, and recall during the delivery of interventions. PMID:21132593

  18. Temporal processes that contribute to nonlinearity in vegetation responses to ozone exposure and dose

    NASA Astrophysics Data System (ADS)

    Heath, Robert L.; Lefohn, Allen S.; Musselman, Robert C.

    Ozone interacts with plant tissue through distinct temporal processes. Sequentially, plants are exposed to ambient O 3 that (1) moves through the leaf boundary layer, (2) is taken up into plant tissue primarily through stomata, and (3) undergoes chemical interaction within plant tissue, first by initiating alterations and then as part of plant detoxification and repair. In this paper, we discuss the linkage of the temporal variability of apoplastic ascorbate with the diurnal variability of defense mechanisms in plants and compare this variability with daily maximum O 3 concentration and diurnal uptake and entry of O 3 into the plant through stomata. We describe the quantitative evidence on temporal variability in concentration and uptake and find that the time incidence for maximum defense does not necessarily match diurnal patterns for maximum O 3 concentration or maximum uptake. We suggest that the observed out-of-phase association of the diurnal patterns for the above three processes produces a nonlinear relationship that results in a greater response from the higher hourly average O 3 concentrations than from the lower or mid-level values. The fact that these out-of-phase processes affect the relationship between O 3 exposure/dose and vegetation effects ultimately impact the ability of flux-based indices to predict vegetation effects accurately for purposes of standard setting and critical levels. Based on the quantitative aspect of temporal variability identified in this paper, we suggest that the inclusion of a diurnal pattern for detoxification in effective flux-based models would improve the predictive characteristics of the models. While much of the current information has been obtained using high O 3 exposures, future research results derived from laboratory biochemical experiments that use short but elevated O 3 exposures should be combined with experimental results that use ambient-type exposures over longer periods of time. It is anticipated that

  19. 5-a-day Power Plus: process evaluation of a multicomponent elementary school program to increase fruit and vegetable consumption.

    PubMed

    Story, M; Mays, R W; Bishop, D B; Perry, C L; Taylor, G; Smyth, M; Gray, C

    2000-04-01

    The 5-a-Day Power Plus program targeted multiethnic fourth- and fifth-grade students in 10 intervention and 10 control urban elementary schools in St. Paul, Minnesota, to increase fruit and vegetable consumption. The intervention included behavioral curricula in classrooms, parental involvement, school food service changes, and food industry support. Process evaluation was conducted by using surveys and classroom and lunchroom observations to assess the characteristics of teachers and food service staff, the degree the intervention was implemented as intended, and exteral factors that may have affected the program results. Results showed high levels of participation, dose, and fidelity for all of the intervention components, with the exception of parental involvement. The process evaluation findings help explain why the increase in fruit and vegetable consumption occurred mostly at school lunch and not at home. Future intervention research should focus on creating new and potent strategies for parental involvement and for increasing the appeal and availability of vegetables. PMID:10768800

  20. The effect of High Pressure and High Temperature processing on carotenoids and chlorophylls content in some vegetables.

    PubMed

    Sánchez, Celia; Baranda, Ana Beatriz; Martínez de Marañón, Iñigo

    2014-11-15

    The effect of High Pressure (HP) and High Pressure High Temperature (HPHT) processing on carotenoid and chlorophyll content of six vegetables was evaluated. In general, carotenoid content was not significantly influenced by HP or HPHT treatments (625 MPa; 5 min; 20, 70 and 117 °C). Regarding chlorophylls, HP treatment caused no degradation or slight increases, while HPHT processes degraded both chlorophylls. Chlorophyll b was more stable than chlorophyll a at 70 °C, but both of them were highly degraded at 117 °C. HPHT treatment at 117 °C provided products with a good retention of carotenoids and colour in the case of red vegetables. Even though the carotenoids also remained in the green vegetables, their chlorophylls and therefore their colour were so affected that milder temperatures need to be applied. As an industrial scale equipment was used, results will be useful for future industrial implementation of this technology. PMID:24912693

  1. Effect of combination processing on the microbial, chemical and sensory quality of ready-to-eat (RTE) vegetable pulav

    NASA Astrophysics Data System (ADS)

    Kumar, R.; George, Johnsy; Rajamanickam, R.; Nataraju, S.; Sabhapathy, S. N.; Bawa, A. S.

    2011-12-01

    Effect of irradiation in combination with retort processing on the shelf life and safety aspects of an ethnic Indian food product like vegetable pulav was investigated. Gamma irradiation of RTE vegetable pulav was carried out at different dosage rates with 60Co followed by retort processing. The combination processed samples were analysed for microbiological, chemical and sensory characteristics. Microbiological analysis indicated that irradiation in combination with retort processing has significantly reduced the microbial loads whereas the chemical and sensory analysis proved that this combination processing is effective in retaining the properties even after storage for one year at ambient conditions. The results also indicated that a minimum irradiation dosage at 4.0 kGy along with retort processing at an F0 value of 2.0 is needed to achieve the desired shelf life with improved organoleptic qualities.

  2. What Works? Process Evaluation of a School-Based Fruit and Vegetable Distribution Program in Mississippi

    ERIC Educational Resources Information Center

    Potter, Susan C.; Schneider, Doris; Coyle, Karin K.; May, Gary; Robin, Leah; Seymour, Jenna

    2011-01-01

    Background: During the 2004-2005 school year, the Mississippi Department of Education, Office of Child Nutrition, initiated a pilot program to distribute free fruit and vegetable snacks to students during the school day. This article describes the first-year implementation of the Mississippi Fruit and Vegetable Pilot Program. Methods: The process…

  3. Identifying vegetation's influence on multi-scale fluvial processes based on plant trait adaptations

    NASA Astrophysics Data System (ADS)

    Manners, R.; Merritt, D. M.; Wilcox, A. C.; Scott, M.

    2015-12-01

    Riparian vegetation-geomorphic interactions are critical to the physical and biological function of riparian ecosystems, yet we lack a mechanistic understanding of these interactions and predictive ability at the reach to watershed scale. Plant functional groups, or groupings of species that have similar traits, either in terms of a plant's life history strategy (e.g., drought tolerance) or morphology (e.g., growth form), may provide an expression of vegetation-geomorphic interactions. We are developing an approach that 1) identifies where along a river corridor plant functional groups exist and 2) links the traits that define functional groups and their impact on fluvial processes. The Green and Yampa Rivers in Dinosaur National Monument have wide variations in hydrology, hydraulics, and channel morphology, as well as a large dataset of species presence. For these rivers, we build a predictive model of the probable presence of plant functional groups based on site-specific aspects of the flow regime (e.g., inundation probability and duration), hydraulic characteristics (e.g., velocity), and substrate size. Functional group traits are collected from the literature and measured in the field. We found that life-history traits more strongly predicted functional group presence than did morphological traits. However, some life-history traits, important for determining the likelihood of a plant existing along an environmental gradient, are directly related to the morphological properties of the plant, important for the plant's impact on fluvial processes. For example, stem density (i.e., dry mass divided by volume of stem) is positively correlated to drought tolerance and is also related to the modulus of elasticity. Growth form, which is related to the plant's susceptibility to biomass-removing fluvial disturbances, is also related to frontal area. Using this approach, we can identify how plant community composition and distribution shifts with a change to the flow

  4. Improved simulation of fire-vegetation interactions in the Land surface Processes and eXchanges dynamic global vegetation model (LPX-Mv1)

    NASA Astrophysics Data System (ADS)

    Kelley, D. I.; Harrison, S. P.; Prentice, I. C.

    2014-01-01

    The Land surface Processes and eXchanges (LPX) model is a fire-enabled dynamic global vegetation model that performs well globally but has problems representing fire regimes and vegetative mix in savannas. Here we focus on improving the fire module. To improve the representation of ignitions, we introduced a treatment of lightning that allows the fraction of ground strikes to vary spatially and seasonally, realistically partitions strike distribution between wet and dry days, and varies the number of dry-days with strikes. Fuel availability and moisture content were improved by implementing decomposition rates specific to individual plant functional types and litter classes, and litter drying rates driven by atmospheric water content. To improve water extraction by grasses, we use realistic plant-specific treatments of deep roots. To improve fire responses, we introduced adaptive bark thickness and post-fire resprouting for tropical and temperate broadleaf trees. All improvements are based on extensive analyses of relevant observational data sets. We test model performance for Australia, first evaluating parameterisations separately and then measuring overall behaviour against standard benchmarks. Changes to the lightning parameterisation produce a more realistic simulation of fires in southeastern and central Australia. Implementation of PFT-specific decomposition rates enhances performance in central Australia. Changes in fuel drying improve fire in northern Australia, while changes in rooting depth produce a more realistic simulation of fuel availability and structure in central and northern Australia. The introduction of adaptive bark thickness and resprouting produces more realistic fire regimes in savannas, including simulating biomass recovery rates consistent with observations. The new model (LPX-Mv1) improves Australian vegetation composition by 33% and burnt area by 19% compared to LPX.

  5. Advances in processing technologies to preserve and enhance the safety of fresh and fresh-cut fruits and vegetables

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The challenge of providing fruits and vegetables free from contamination with human pathogens has led to the development and optimization of a variety of post-harvest processing technologies. This chapter will summarize recent research related to chemical and physical treatments for fresh and fresh-...

  6. 7 CFR 52.38c - Statistical sampling procedures for lot inspection of processed fruits and vegetables by attributes.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Statistical sampling procedures for lot inspection of processed fruits and vegetables by attributes. 52.38c Section 52.38c Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS...

  7. A Robust Gold Deconvolution Approach for LiDAR Waveform Data Processing to Characterize Vegetation Structure

    NASA Astrophysics Data System (ADS)

    Zhou, T.; Popescu, S. C.; Krause, K.; Sheridan, R.; Ku, N. W.

    2014-12-01

    Increasing attention has been paid in the remote sensing community to the next generation Light Detection and Ranging (lidar) waveform data systems for extracting information on topography and the vertical structure of vegetation. However, processing waveform lidar data raises some challenges compared to analyzing discrete return data. The overall goal of this study was to present a robust de-convolution algorithm- Gold algorithm used to de-convolve waveforms in a lidar dataset acquired within a 60 x 60m study area located in the Harvard Forest in Massachusetts. The waveform lidar data was collected by the National Ecological Observatory Network (NEON). Specific objectives were to: (1) explore advantages and limitations of various waveform processing techniques to derive topography and canopy height information; (2) develop and implement a novel de-convolution algorithm, the Gold algorithm, to extract elevation and canopy metrics; and (3) compare results and assess accuracy. We modeled lidar waveforms with a mixture of Gaussian functions using the Non-least squares (NLS) algorithm implemented in R and derived a Digital Terrain Model (DTM) and canopy height. We compared our waveform-derived topography and canopy height measurements using the Gold de-convolution algorithm to results using the Richardson-Lucy algorithm. Our findings show that the Gold algorithm performed better than the Richardson-Lucy algorithm in terms of recovering the hidden echoes and detecting false echoes for generating a DTM, which indicates that the Gold algorithm could potentially be applied to processing of waveform lidar data to derive information on terrain elevation and canopy characteristics.

  8. Demonstration of wetland vegetation mapping in Florida from computer-processed satellite and aircraft multispectral scanner data

    NASA Technical Reports Server (NTRS)

    Butera, M. K.

    1979-01-01

    The success of remotely mapping wetland vegetation of the southwestern coast of Florida is examined. A computerized technique to process aircraft and LANDSAT multispectral scanner data into vegetation classification maps was used. The cost effectiveness of this mapping technique was evaluated in terms of user requirements, accuracy, and cost. Results indicate that mangrove communities are classified most cost effectively by the LANDSAT technique, with an accuracy of approximately 87 percent and with a cost of approximately 3 cent per hectare compared to $46.50 per hectare for conventional ground survey methods.

  9. Microbial-processing of fruit and vegetable wastes for production of vital enzymes and organic acids: Biotechnology and scopes.

    PubMed

    Panda, Sandeep K; Mishra, Swati S; Kayitesi, Eugenie; Ray, Ramesh C

    2016-04-01

    Wastes generated from fruits and vegetables are organic in nature and contribute a major share in soil and water pollution. Also, green house gas emission caused by fruit and vegetable wastes (FVWs) is a matter of serious environmental concern. This review addresses the developments over the last one decade on microbial processing technologies for production of enzymes and organic acids from FVWs. The advances in genetic engineering for improvement of microbial strains in order to enhance the production of the value added bio-products as well as the concept of zero-waste economy have been briefly discussed. PMID:26761593

  10. CO₂ processing and hydration of fruit and vegetable tissues by clathrate hydrate formation.

    PubMed

    Takeya, Satoshi; Nakano, Kohei; Thammawong, Manasikan; Umeda, Hiroki; Yoneyama, Akio; Takeda, Tohoru; Hyodo, Kazuyuki; Matsuo, Seiji

    2016-08-15

    CO2 hydrate can be used to preserve fresh fruits and vegetables, and its application could contribute to the processing of carbonated frozen food. We investigated water transformation in the frozen tissue of fresh grape samples upon CO2 treatment at 2-3 MPa and 3°C for up to 46 h. Frozen fresh bean, radish, eggplant and cucumber samples were also investigated for comparison. X-ray diffraction indicated that after undergoing CO2 treatment for several hours, structure I CO2 hydrate formed within the grape tissue. Phase-contrast X-ray imaging using the diffraction-enhanced imaging technique revealed the presence of CO2 hydrate within the intercellular spaces of these tissues. The carbonated produce became effervescent because of the dissociation of CO2 hydrate through the intercellular space, especially above the melting point of ice. In addition, suppressed metabolic activity resulting from CO2 hydrate formation, which inhibits water and nutrient transport through intercellular space, can be expected. PMID:27006222

  11. Determination of 5-log pathogen reduction times for heat-processed, acidified vegetable brines.

    PubMed

    Breidt, F; Hayes, J S; Osborne, J A; McFeeters, R F

    2005-02-01

    Recent outbreaks of acid-resistant food pathogens in acid foods, including apple cider and orange juice, have raised concerns about the safety of acidified vegetable products. We determined pasteurization times and temperatures needed to assure a 5-log reduction in the numbers of Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella strains in acidified cucumber pickle brines. Cocktails of five strains of each pathogen were (separately) used for heat-inactivation studies between 50 and 60 degrees C in brines that had an equilibrated pH value of 4.1. Salmonella strains were found to be less heat resistant than E. coli O157:H7 or L. monocytogenes strains. The nonlinear killing curves generated during these studies were modeled using a Weibull function. We found no significant difference in the heat-killing data for E. coli O157:H7 and L. monocytogenes (P = 0.9709). The predicted 5-log reduction times for E. coli O157:H7 and L. monocytogenes were found to fit an exponential decay function. These data were used to estimate minimum pasteurization times and temperatures needed to ensure safe processing of acidified pickle products and show that current industry pasteurization practices offer a significant margin of safety. PMID:15726973

  12. Occurrence of rhodamine B contamination in capsicum caused by agricultural materials during the vegetation process.

    PubMed

    Gao, Wei; Wu, Naiying; Du, Jingjing; Zhou, Li; Lian, Yunhe; Wang, Lei; Liu, Dengshuai

    2016-08-15

    This paper reports on the environmental rhodamine B (RhB) contamination in capsicum caused by agricultural materials during the vegetation process. Ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) was applied to detect 64 capsicum samples from China, Peru, India and Burma. Results demonstrated that RhB was found in all samples at low concentrations (0.11-0.98 μg/kg), indicating RhB contamination in capsicums is probably a ubiquitous phenomenon. In addition, studies into soils, roots, stems and leaves in Handan of Hebei province, China showed that the whole ecologic chain had been contaminated with RhB with the highest levels in leaves. The investigation into the agricultural environment in Handan of Hebei province and Korla of Xinjiang province, China demonstrated that the appearances of RhB contamination in the tested capsicums are mainly due to the agricultural materials contamination. The study verified that environmental contamination should be an important origin for the RhB contamination in capsicum fruits. PMID:27006220

  13. Post-fire Gully Rejuvenation - Evidence of Process Thresholds Controlled by Vegetation Disturbance

    NASA Astrophysics Data System (ADS)

    Hyde, K.; Woods, S.

    2011-12-01

    High intensity rainfall may trigger gully rejuvenation on hillslopes recently disturbed by wildfire, leading to debris-laden flows which generally contribute the majority of sediment transported in post-fire erosion events. We investigated the extent to which the occurrence of gully rejuvenation can be predicted based upon burn severity, rainfall data and basin morphometric variables. Field surveys were conducted at six Northern Rockies sites to identify occurrence of gully rejuvenation in first order catchments and to map and characterize the location of gully heads. NEXRAD and rain gage data analysis coupled with field observations characterized rainfall intensity and extent. Building on previous work we quantified burn severity using the Vegetation Disturbance Index (VDI), a continuous metric based upon Burned Area Reflectance Classification (BARC) maps derived from satellite imagery using the dNBR algorithm. GIS analysis combined the VDI with morphometric factors expected to influence hillslope stability. Gully heads marked abrupt transition in channel form. Above gully heads, channels were shallow and U-shaped with gentle transition to the hillslope and fine root hairs intact. Angular edges marked deep gully head incisions which down-cut channel floors from 0.2-0.3 to 1.0 meter or more. Any remaining roots were coarse and the hillslope transition was sharp. Gully heads were located at variable distances below the master rill head of the catchment hollow. Distances were obviously greater where live canopy remained upslope. Gully head morphology strongly suggests flow force transition and exceedance of an erosion process threshold. The variable distance of the gully head below the hollow suggest upslope controls influencing initiation point, possibly degree and spatial pattern of burn severity. Binary logistic regression revealed stronger correlation between gully rejuvenation and VDI than morphometric variables. The statistical strength using the continuous

  14. Geomorphic and vegetation processes of the Willamette River floodplain, Oregon: current understanding and unanswered science questions

    USGS Publications Warehouse

    Wallick, J. Rose; Jones, Krista L.; O'Connor, Jim E.; Keith, Mackenzie K.; Hulse, David; Gregory, Stanley V.

    2013-01-01

    This report summarizes the current understanding of floodplain processes and landforms for the Willamette River and its major tributaries. The area of focus encompasses the main stem Willamette River above Newberg and the portions of the Coast Fork Willamette, Middle Fork Willamette, McKenzie, and North, South and main stem Santiam Rivers downstream of U.S. Army Corps of Engineers dams. These reaches constitute a large portion of the alluvial, salmon-bearing rivers in the Willamette Basin. The geomorphic, or historical, floodplain of these rivers has two zones - the active channel where coarse sediment is mobilized and transported during annual flooding and overbank areas where fine sediment is deposited during higher magnitude floods. Historically, characteristics of the rivers and geomorphic floodplain (including longitudinal patterns in channel complexity and the abundance of side channels, islands and gravel bars) were controlled by the interactions between floods and the transport of coarse sediment and large wood. Local channel responses to these interactions were then shaped by geologic features like bedrock outcrops and variations in channel slope. Over the last 150 years, floods and the transport of coarse sediment and large wood have been substantially reduced in the basin. With dam regulation, nearly all peak flows are now confined to the main channels. Large floods (greater than 10-year recurrence interval prior to basinwide flow regulation) have been largely eliminated. Also, the magnitude and frequency of small floods (events that formerly recurred every 2–10 years) have decreased substantially. The large dams trap an estimated 50–60 percent of bed-material sediment—the building block of active channel habitats—that historically entered the Willamette River. They also trap more than 80 percent of the estimated bed material in the lower South Santiam River and Middle and Coast Forks of the Willamette River. Downstream, revetments further

  15. A new process for producing calcium acetate from vegetable wastes for use as an environmentally friendly deicer.

    PubMed

    Jin, Fangming; Zhang, Guangyi; Jin, Yujia; Watanabe, Yosiyuki; Kishita, Atsushi; Enomoto, Heiji

    2010-10-01

    A new process for producing calcium acetate, a non-corrosive deicer, is proposed. The process consists of a two-step continuous-flow hydrothermal conversion of vegetable wastes into acetic acid and the production of calcium acetate, followed by the separation and condensation of the product. The experiments for acetic acid production showed that there were almost no significant differences in acetic acid yields for the five different kinds of vegetables selected for the batch experiments or for their mixture in batch and continuous-flow experiments. Electrodialysis was chosen as a satisfactory method for separating and condensing the calcium acetate produced from the acetic acid solution obtained from the vegetable wastes. After purification by reverse-osmosis, the residual, depleted acid solution could be safely discharged. The calculation of the carbon balance for the proposed process showed that 21.3% of the TOC from vegetable wastes could be used as calcium/magnesium acetate (CMA) and over 22% as an environmentally friendly deicer. PMID:20483594

  16. Control of Aeromonas on minimally processed vegetables by decontamination with lactic acid, chlorinated water, or thyme essential oil solution.

    PubMed

    Uyttendaele, M; Neyts, K; Vanderswalmen, H; Notebaert, E; Debevere, J

    2004-02-01

    Aeromonas is an opportunistic pathogen, which, although in low numbers, may be present on minimally processed vegetables. Although the intrinsic and extrinsic factors of minimally processed prepacked vegetable mixes are not inhibitory to the growth of Aeromonas species, multiplication to high numbers during processing and storage of naturally contaminated grated carrots, mixed lettuce, and chopped bell peppers was not observed. Aeromonas was shown to be resistant towards chlorination of water, but was susceptible to 1% and 2% lactic acid and 0.5% and 1.0% thyme essential oil treatment, although the latter provoked adverse sensory properties when applied for decontamination of chopped bell peppers. Integration of a decontamination step with 2% lactic acid in the processing line of grated carrots was shown to have the potential to control the overall microbial quality of the grated carrots and was particularly effective towards Aeromonas. PMID:14751681

  17. Effect of novel ultrasound based processing on the nutrition quality of different fruit and vegetable juices.

    PubMed

    Khandpur, Paramjeet; Gogate, Parag R

    2015-11-01

    Increasing consumer awareness regarding the health benefits of different nutrients in food have led to the requirement of assessing the effect of food processing approaches on the quality attributes. The present work focuses on understanding the effects of novel approaches based on the use of ultrasound and ultraviolet irradiations on the nutritional quality of different fruit and vegetable juices (orange, sweet lime, carrot and spinach juices) and its comparison with the conventional thermal pasteurization operated at 80°C for 10 min. The ultrasound sterilization parameters were maintained at ultrasound frequency of 20 kHz and power of 100 W with treatment time as 15 min. For the case of ultraviolet irradiations, 2 UVC lamps (254 nm) of 8 W were placed in parallel on either sides of the reactor. The treated juices were analyzed for total phenol content, antioxidant activity, vitamin C, carbohydrates etc. It has been established that ultrasound processed juice retained most of the nutrient components to higher extent in comparison to all the other techniques used in the work. Combination of ultrasound and ultraviolet irradiations used to achieve an effective decontamination of juices (recommended 5 log reduction of microorganisms) also retained nutrients to a higher level in comparison to the thermal method; however some losses were observed as compared to the use of only ultrasound which could be attributed to inefficient heat exchange in the combined approach. A scale up attempt was also made for treatment of spinach juice using ultrasonic reactors and analysis for quality attributes confirmed that the juice satisfied the criteria of required nutrient contents for 18 days shelf life trial in refrigerated storage conditions. The present work has clearly established the usefulness of ultrasound based treatment in maintaining the nutritional quality of beverages while giving enhanced shelf life as compared to the conventional approaches. PMID:26186829

  18. Geomorphic and vegetative recovery processes along modified stream channels of West Tennessee

    USGS Publications Warehouse

    Simon, Andrew; Hupp, C.R. Tennessee

    1992-01-01

    Hundreds of miles of streams in West Tennessee have been channelized or otherwise modt@ed since the turn of century. After all or parts of a stream are straightened, dredged, or cleared, systematic hydrologic, geomorphic, and ecologic processes collectively begin to reduce energy conditions towards the premodified state. One hundred and five sites along 15 streams were studied in the Obion, Forked Deer, Hatchie, and Wolf River basins. All studied streams, except the Hatchie River, have had major channel modi@cation along all or parts of their courses. Bank material shear-strength properties were determined through drained borehole-shear testing (168 tests) and used to interpret present critical bank conditions and factors of safety, and to estimate future channel-bank stability. Mean values of cohesive strength and angle of internal friction were 1.26 pounds per square inch and 30.1 degrees, respectively. Dendrogeomorphic analyses were made using botanical evidence of channel-bank failures to determine rates of channel widening; buried riparian stems were analyzed to determine rates of bank accretion. Channel bed-level changes through time and space were represented by a power equation. Plant ecological analyses were ma& to infer relative bank stability, to identify indicator species of the stage of bank recovery, and to determine patterns of vegetation development through the course of channel evolution. Quantitative data on morphologic changes were used with previously developed six-stage models of channel evolution and bank-slope development to estimate trends of geomorphic and ecologic processes and forms through time. Immediately after channel modr@cations, a 10- to 1%yearperiod of channel-bed degradation ensues at and upstream from the most recent modifications (area of maximum disturbance). Channel-bed lowering by &gradation was as much as 20 feet along some stream reaches. Downstream from the area of maximum disturbance, the bed was aggraded by the

  19. Vegetable dietary fibres made with minimal processing improve health-related faecal parameters in a valid rat model.

    PubMed

    Monro, John; Mishra, Suman; Redman, Claire; Somerfield, Sheryl; Ng, Jovyn

    2016-06-15

    Dietary fibre-induced faecal bulking and hydration are important contributors to large bowel function and health, and are affected by the dietary fibre structure. To determine faecal bulk-related parameters for vegetable dietary fibres with retained structure, cold water fragmentation of vegetables was used to make minimally processed vegetable fibres (MPVF) from swede, broccoli and asparagus. A valid adult rat model was used to subject the fibres to processes of hind gut fermentation and faecal accumulation similar to those in humans. All the MPVFs had high faecal bulking indexes (FBIs, mean ± sem: wheat bran (reference), 100 ± 6.0; asparagus 168 ± 5.7; swede 135 ± 6.1; broccoli 135 ± 5.9; broccoli rind 205 ± 10.4), and caused large increases in the theoretical colonic water load at 10 g per 100 g diet (increase over baseline (%): wheat bran, 137 ± 8.3; asparagus, 236 ± 25, swede 193 ± 8.8; broccoli 228 ± 12; broccoli rind 223 ± 8.5). Faecal bulking by MPVFs was much greater than by fermentable extracted polysaccharides such as pectin and raftilose, or by commercial fibres made from highly processed cell walls. The results show natural, non-degraded vegetable fibres with retained botanical structure have beneficial effects not provided by structure-less fermentable dietary fibres. Dietary fibre-deficient diets supplemented with prebiotics cannot, therefore, adequately substitute for varied diets containing adequate vegetables, fruits and wholegrain cereals in which fermentation is associated with enough retained structure to conserve physicochemical properties of benefit to colonic function. PMID:27219511

  20. Vegetation controls on variably saturated processes between surface water and groundwater and their impact on the state of connection

    NASA Astrophysics Data System (ADS)

    Banks, E. W.; Brunner, P.; Simmons, C. T.

    2011-11-01

    The vadose zone plays an important role in surface water-groundwater interaction and exerts strong influences on biogeochemical, ecological, and hyporheic processes. It is also the presence of an unsaturated zone that controls the state of connection between surface water and groundwater. Despite recent advances on how hydrogeological variables affect surface water-groundwater interactions, there is limited understanding of the hydroclimatic effects of precipitation and evapotranspiration. More specifically, there is a need for a physically based understanding on the changes that may occur in response to changes in vegetation. While it may seem qualitatively obvious that the presence of vegetation can cause an unsaturated zone to develop underneath a riverbed and alter the state of connection, it has so far not been demonstrated quantitatively. Also, the influence of variables such as root extinction depth, topography, and the influence of land clearance has so far not been explored. In this study, fully coupled, physically based 2-D transient homogeneous models were used to simulate the impact of land clearance and revegetation on the state of connection of a perennial river system. The simulations showed that the presence of vegetation can create an unsaturated zone between a river and an aquifer and affect the state of connection and that the removal of deep-rooted vegetation from a catchment may have a significant impact on the state of connection as well as the condition of the water resource.

  1. Geomorphic process and vegetation diversity in the active riverbed and the floodplain in the Kamikochi valley, central Japan

    NASA Astrophysics Data System (ADS)

    Shimazu, H.

    2012-04-01

    The Kamikochi valley is located in a mountainous area in central Japan. The R. Azusa in this valley is a braided river with floodplains. Dense riparian forests cover the floodplains and fragmented small pioneer plant patches and isolated old pioneer trees are distributed in the active riverbed. This study aims to discuss the relationships between geomorphic processes of the river and vegetation diversity. Yearly mapping of the riverbed micro-landforms revealed that channel migrations and landform changes in the active riverbed occurs once every one or several years during a bankfull flood in the rainy season. Germination ages of riparian trees using a dendrochronological technique, their established layers and landform structure were examined to reconstruct floodplain dynamics. Major channel migrations destroyed the riparian forest repeatedly and the recent event occurred about 100 years ago. This caused a longitudinal zonal structure of the riparian forest vegetation, elm-fir forest, mature pioneer forest and young pioneer forests. The young pioneer forest is located alongside the present riverbed. The mature pioneer forest lies between the older elm-fir forests. The pioneer plants germinated simultaneously on the abandoned channel after channel migration. These trees became the mature pioneer forest. Ditches and lobes including boulders are found in the floodplain. The ditches extend parallel to the direction of the present and former channels. The lobes are distributed alongside them. Younger trees under the canopy grow on the lobes in the inner part of the floodplain. These young trees and lobes show that dominant sedimentation process in the floodplain is not lateral flooding, but longitudinal flooding. Sediments from the present channel flew downward through the ditches and were overflowed on the floodplain. This process destroyed the vegetation in and alongside the ditches causing vegetation diversity in the inner part of the riparian forest. Several species

  2. Process Evaluation of the Fresh Fruit and Vegetable Program Implementation in a New Jersey Elementary School

    ERIC Educational Resources Information Center

    Bai, Yeon; Feldman, Charles; Wunderlich, Shahla M.; Aletras, Stefanie C.

    2011-01-01

    Purpose/Objectives: The U.S. Department of Agriculture provides funding to elementary schools for the Fresh Fruit and Vegetable Program (FFVP) to encourage healthy eating. The purpose of this study was to examine factors facilitating or challenging the program's successful implementation in one New Jersey school. Methods: Researchers conducted an…

  3. 75 FR 6364 - Process for Requesting a Variance From Vegetation Standards for Levees and Floodwalls

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-09

    ... regulations.gov Web site is an anonymous access system, which means we will not know your identity or contact..., floodwalls, and appurtenant structures contained in Engineer Technical Letter (ETL) 1110-2-571-- Guidelines... Technical Letter (ETL) 1110-2-571, Guidelines for Landscape Planting and Vegetation Management at...

  4. When Fruits and Vegetables Are Optional, Elementary School Children Choose Processed over Whole Offerings

    ERIC Educational Resources Information Center

    Amin, Sarah A.; Yon, Bethany A.; Taylor, Jennifer C.; Johnson, Rachel K.

    2014-01-01

    Purpose/Objectives: Increasing children's fruit and vegetable (FV) consumption is an important goal for the National School Lunch Program (NSLP). In 2012 the NSLP began requiring students to select a FV. The objective of this study was to compare children's FV choices in two school cafeteria environments a year before these new USDA…

  5. ISSUES IN DIGITAL IMAGE PROCESSING OF AERIAL PHOTOGRAPHY FOR MAPPING SUBMERSED AQUATIC VEGETATION

    EPA Science Inventory

    The paper discusses the numerous issues that needed to be addressed when developing a methodology for mapping Submersed Aquatic Vegetation (SAV) from digital aerial photography. Specifically, we discuss 1) choice of film; 2) consideration of tide and weather constraints; 3) in-s...

  6. Effect of home food processing on chlordecone (organochlorine) content in vegetables.

    PubMed

    Clostre, Florence; Letourmy, Philippe; Thuriès, Laurent; Lesueur-Jannoyer, Magalie

    2014-08-15

    Decades after their use and their ban, organochlorine pesticides still pollute soil, water and food and lead to human and ecosystem exposure. In the case of chlordecone, human exposure is mainly due to the consumption of polluted food. We studied the effect of preparation and cooking in five vegetable products, three root vegetables (yam, dasheen and sweet potato) and two cucurbits (cucumber and pumpkin), among the main contributors to exposure to chlordecone in food in the French West Indies. Boiling the vegetables in water had no effect on chlordecone content of the vegetables and consequently on consumer exposure. The peel was three to 40-fold more contaminated than the pulp except cucumber, where the difference was less contrasted. The edible part is thus significantly less contaminated and peeling is recommended after rinsing to reduce consumer exposure, particularly for food grown in home gardens with contaminated soils. The type of soil had no consistent effect on CLD distribution but plot did. Peel and pulp composition (lipids and fibers) appear to partially account for CLD distribution in the product. PMID:24914532

  7. Field application of glyphosate induces molecular changes affecting vegetative growth processes in leafy spurge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recommended rates of glyphosate for non-cultivated areas destroy the aboveground shoots of the perennial plant leafy spurge. However, such applications cause little or no damage to underground adventitious buds (UABs), and thus the plant readily regenerates vegetatively. High concentrations of glyph...

  8. Outcome and Process Evaluation of a Norwegian School-Randomized Fruit and Vegetable Intervention: Fruits and Vegetables Make the Marks (FVMM)

    ERIC Educational Resources Information Center

    Bere, E.; Veierod, M. B.; Bjelland, M.; Klepp, K.-I.

    2006-01-01

    This study reports the effect of the Fruits and Vegetables Make the Marks intervention, a school-based fruit and vegetable intervention consisting of a home economics classroom component and parental involvement and encouraged participation in the Norwegian School Fruit Programme, all delivered during the school year of 2001-02. Nine randomly…

  9. Impacts of the 2014 Drought on Vegetation Processes in the Sierra Nevada of California

    NASA Astrophysics Data System (ADS)

    Loik, M. E.; Wade, C. E.; Reed, C. C.

    2014-12-01

    Sierra Nevada snowpack provides over 60 percent of California's freshwater supplies. The drought of 2014 has been unprecedented in the state's history, and followed below-average precipitation for the hydrologic years 2012 and 2013. Record-low precipitation has resulted in minimal Sierra Nevada snow pack and runoff, and massive reductions in reservoir storage, which has triggered widespread drought adaptation measures for one of the world's largest economies. We assessed the impacts of the 2014 drought on vegetation processes in the headwaters of the Owens River, which is one of the main watersheds for the city of Los Angeles. We monitored water relations, photosynthesis, growth and Leaf Area Index of tree, shrub, herb, and grass species. In order to better understand the effects of drought, we examined responses to watering manipulations, long-term snow fences, elevation gradient analysis, and comparisons to previous wetter years. 1 April 2014 snow pack depth was 330 mm (average for 1928 - 2012 = 1344 mm, CV = 49%). Despite widespread mortality of Pinus jeffreyi saplings (mean 1.5 m tall) at 2300 m, older trees as well as saplings of Pinus contorta showed new growth. There were no significant differences in water potential (Ψ) for the two conifer species in a wet year (2006, 1 April snow depth = 2240 mm) vs. 2014. Water potential for P. contorta in 2014 was higher at 2900 m than at 2300 m but photosynthetic CO2 assimilation (A) and stomatal conductance (gs), were not different. By contrast, Ψ, A, gs, Vcmax and Jmax for the widespread shrub Artemisia tridentata increased along a gradient from 2100 m to 2900 m in 2014. Watering only significantly increased these photosynthetic parameters at the lowest, driest elevation. At the middle elevation, Leaf Area Index in 2014 was about 20% of the 2006 value for the N-fixing shrub Purshia tridentata. Results show reductions in photosynthesis and growth for some species but not others in response to the severe drought

  10. Initial adjustments within a new river channel: Interactions between fluvial processes, colonizing vegetation, and bank profile development.

    PubMed

    Gurnell, Angela M; Morrissey, Ian P; Boitsidis, Angela J; Bark, Tony; Clifford, Nicholas J; Petts, Geoffrey E; Thompson, Kenneth

    2006-10-01

    A conceptual model of the morphological development of the riparian margins of newly cut river channels is presented, suggesting early feedbacks between vegetation growth and bank form. To test the model, observations of long and cross profiles, bank sediment and seed deposition, and bank vegetation development were collected over the first 2 years of river flows through a reach of the River Cole, West Midlands, UK. The newly created channel had a sinuous planform and varying asymmetric trapezoidal cross section in sympathy with the planform. No imposed bedforms or bank reseeding were included in the design. Over the 2 years, development of bedforms was rapid, with bed sediment sorting and bank profile adjustment occurring more steadily and progressively. Six classes of bank profile were identified by the end of the study period, illustrating close associations with sediment aggradation, vegetation colonization, and growth patterns. Vegetation colonization of the banks was seeded predominantly from local sources during the summer and from hydrochory (transport by the river) during the winter. Colonizing vegetation on the riverbanks appeared to act as a significant propagule source by the second summer and as an increasingly important roughness element, trapping both propagules and sediment, within the second year and providing early feedback into bank evolution. As a result, the time required for riparian margin development in the conceptual model was found to be considerably longer than observed in the study river. In addition, the role of surface wash/bank failure in modifying the bank profile and transporting seeds onto the upper bank face during the first year of bank development was found to be important in initiating rapid bank vegetation colonization and surface stabilization. This set of processes had not been incorporated in the initial conceptual model. In relation to channel restoration, this research illustrates that in small temperate rivers of modest

  11. Archaeal community dynamics and abiotic characteristics in a mesophilic anaerobic co-digestion process treating fruit and vegetable processing waste sludge with chopped fresh artichoke waste.

    PubMed

    Ros, M; Franke-Whittle, I H; Morales, A B; Insam, H; Ayuso, M; Pascual, J A

    2013-05-01

    This study evaluated the feasibility of obtaining methane in anaerobic digestion (AD) from the waste products generated by the processing of fruit and vegetables. During the first phase (0-55 d) of the AD using sludge from fruit and vegetable processing, an average value of 244±88 L kg(-1) dry matter d(-1)of biogas production was obtained, and methane content reached 65% of the biogas. Co-digestion with chopped fresh artichoke wastes in a second phase (55-71 d) enhanced biogas production, and resulted in an average value of 354±68 L kg(-1) dry matter d(-1), with higher methane content (more than 70%). The archaeal community involved in methane production was studied using the ANAEROCHIP microarray and real-time PCR. Results indicated that species of Methanosaeta and Methanosarcina were important during the AD process. Methanosarcina numbers increased after the addition of chopped fresh artichoke, while Methanosaeta numbers decreased. PMID:23548398

  12. An ecological vegetation-activated sludge process (V-ASP) for decentralized wastewater treatment: system development, treatment performance, and mathematical modeling.

    PubMed

    Yuan, Jiajia; Dong, Wenyi; Sun, Feiyun; Li, Pu; Zhao, Ke

    2016-05-01

    An environment-friendly decentralized wastewater treatment process that is comprised of activated sludge process (ASP) and wetland vegetation, named as vegetation-activated sludge process (V-ASP), was developed for decentralized wastewater treatment. The long-term experimental results evidenced that the vegetation sequencing batch reactor (V-SBR) process had consistently stable higher removal efficiencies of organic substances and nutrients from domestic wastewater compared with traditional sequencing batch reactor (SBR). The vegetation allocated into V-SBR system could not only remove nutrients through its vegetation transpiration ratio but also provide great surface area for microorganism activity enhancement. This high vegetation transpiration ratio enhanced nutrients removal effectiveness from wastewater mainly by flux enhancement, oxygen and substrate transportation acceleration, and vegetation respiration stimulation. A mathematical model based on ASM2d was successfully established by involving the specific function of vegetation to simulate system performance. The simulation results on the influence of operational parameters on V-ASP treatment effectiveness demonstrated that V-SBR had a high resistance to seasonal temperature fluctuations and influent loading shocking. PMID:26880524

  13. [The inversion processing of vegetation biomass along Yongding River based on multispectral information].

    PubMed

    He, Cheng; Feng, Zhong-Ke; Han, Xu; Sun, Meng-Ying; Gong, Yin-Xi; Gao, Yuan; Dong, Bin

    2012-12-01

    Researching on vegetation biomass using the traditional measurement method is time-consuming and hard sledding, and prediction precision of biomass is always not good because of uncertain influencing factors. The present article aims at the current situation of Hebei-Beijing reach along Yongding River, using the Thematic Mapper data in this place on 20th July 2009 as source data, with the 30 meters Digital Elevation Model data in Beijing and other auxiliary information, meanwhile through field observation data, to find out the possible functional relationship along vegetation biomass and remote sensing image factor. The authros sorted out the vegetation biomass and remote sensing image factor on the sample plot, then set up an inverse model through multiple linear regression analysis, and analyzed the precision of inverse model. After calculating the measured value and predicted value, the authors got the global relative error is -0.025%, the average relative error is -0.016%, and the general predictive precision is 84.56%. The establishment of this model is able to investigate eco-environmental factors on large range timely, quickly and accurately, also can provide the experimental base for the eco-environmental survey on river basin, and make the foundation for the problem diagnosis of ecological environment and the research on ecosystem degradation mechanism of Yongding River. PMID:23427566

  14. Assembly Processes under Severe Abiotic Filtering: Adaptation Mechanisms of Weed Vegetation to the Gradient of Soil Constraints

    PubMed Central

    Nikolic, Nina; Böcker, Reinhard; Kostic-Kravljanac, Ljiljana; Nikolic, Miroslav

    2014-01-01

    Questions Effects of soil on vegetation patterns are commonly obscured by other environmental factors; clear and general relationships are difficult to find. How would community assembly processes be affected by a substantial change in soil characteristics when all other relevant factors are held constant? In particular, can we identify some functional adaptations which would underpin such soil-induced vegetation response? Location Eastern Serbia: fields partially damaged by long-term and large-scale fluvial deposition of sulphidic waste from a Cu mine; subcontinental/submediterranean climate. Methods We analysed the multivariate response of cereal weed assemblages (including biomass and foliar analyses) to a strong man-made soil gradient (from highly calcareous to highly acidic, nutrient-poor soils) over short distances (field scale). Results The soil gradient favoured a substitution of calcicoles by calcifuges, and an increase in abundance of pseudometallophytes, with preferences for Atlantic climate, broad geographical distribution, hemicryptophytic life form, adapted to low-nutrient and acidic soils, with lower concentrations of Ca, and very narrow range of Cu concentrations in leaves. The trends of abundance of the different ecological groups of indicator species along the soil gradient were systematically reflected in the maintenance of leaf P concentrations, and strong homeostasis in biomass N:P ratio. Conclusion Using annual weed vegetation at the field scale as a fairly simple model, we demonstrated links between gradients in soil properties (pH, nutrient availability) and floristic composition that are normally encountered over large geographic distances. We showed that leaf nutrient status, in particular the maintenance of leaf P concentrations and strong homeostasis of biomass N:P ratio, underpinned a clear functional response of vegetation to mineral stress. These findings can help to understand assembly processes leading to unusual, novel combinations

  15. Single-thread channels resulting from a localization process driven by vegetation

    NASA Astrophysics Data System (ADS)

    Narteau, C.; Tal, M.

    2009-12-01

    The unpredictable manner in which braided rivers evolve is in stark contrast to the orderly migration pattern of meandering rivers driven by erosion along outer bends and deposition along inner banks. Braided channels are the default pattern that develops when an unbounded water flow interacts with noncohesive sediment. A series of laboratory experiments demonstrated that plants alone are able to achieve the two key mechanisms to developing meandering: slowing the rate of widening and discouraging channel cutoffs. Plants initially colonized braid-bars that were emergent during low flow. By adding cohesion to the sediment and increasing roughness, vegetation deterred the flow from reoccupying areas which were colonized. By decreasing erosion rates, plants made it possible for deposition along the inner bank to match the rate of erosion along the outer bank. This enabled the channel to develop sinuosity and migrate laterally while suppressing channel splitting and the creation of new channel width. Areas with established vegetation provided stable conditions which promoted new seedling establishment and expansion of the vegetated area. A generic mechanism of width production in the braided state is the opportunistic creation of new channels. As existing flow paths become slightly less favorable, for example by bar deposition or an increase in sinuosity, new ones are readily created in areas that are not currently occupied by flow. By making it more difficult for flow to occupy vegetated areas, plants in effect decouple the transition between wet and dry areas, making it harder for areas that are dry (vegetated) to turn wet (reoccupied by flow) and less likely for areas that are wet to become dry. The net effect is localization of the flow into a single-thread channel with transitions between wet and dry occurring predominantly along the channel margin and driving lateral migration while a single-thread channel remains intact. We are using a 1D cellular automata model

  16. Outcome and process evaluation of a Norwegian school-randomized fruit and vegetable intervention: Fruits and Vegetables Make the Marks (FVMM).

    PubMed

    Bere, E; Veierød, M B; Bjelland, M; Klepp, K-I

    2006-04-01

    This study reports the effect of the Fruits and Vegetables Make the Marks intervention, a school-based fruit and vegetable intervention consisting of a home economics classroom component and parental involvement and encouraged participation in the Norwegian School Fruit Programme, all delivered during the school year of 2001-02. Nine randomly chosen schools received the intervention and 10 schools served as control schools. Participating pupils completed questionnaires at baseline (September 2001), at Follow-up 1 (May-June 2002) and at Follow-up 2 (May 2003). A total of 369 pupils (69%; mean age, 11.3 years at baseline) participated in all three surveys. No effect of the intervention was found for intake of fruit and vegetables eaten at school or all day, neither at Follow-up 1 nor at Follow-up 2. On analysing the effects on potential mediators, significant differences between intervention and control groups were found for Awareness of the five-a-day recommendations only. The intervention programme was rated as very good by the teachers, and the pupils reported that they enjoyed it. However, the intervention failed to change fruit and vegetable intake, probably because it did not succeed in changing the pupils' preferences for or the accessibility of fruit and vegetables--the two strongest correlates of children's fruit and vegetable intake. PMID:16219631

  17. KUREX-91 - A USSR/US study for global climate processes in steppe vegetation

    NASA Technical Reports Server (NTRS)

    Deering, Donald W.; Kozoderov, Vladimir V.

    1992-01-01

    Researchers use satellite remote sensing of the earth's reflected and emitted radiation as correlated indices of the variables they measure on the ground or within the atmosphere. The Kursk 1991 Experiment (KUREX-91) was conducted to develop capabilities for monitoring global change, and to understand how the earth's land-surface vegetation and atmospheric boundary layer interact. The experiment enabled scientific interactions between the international participants, and comparisons of instruments and data. Intensive ground measurements were coordinated with helicopter, aircraft and satellite data acquisitions.

  18. Thermal, High Pressure, and Electric Field Processing Effects on Plant Cell Membrane Integrity and Relevance to Fruit and Vegetable Quality

    PubMed Central

    Gonzalez, Maria E; Barrett, Diane M

    2010-01-01

    Advanced food processing methods that accomplish inactivation of microorganisms but minimize adverse thermal exposure are of great interest to the food industry. High pressure (HP) and pulsed electric field (PEF) processing are commercially applied to produce high quality fruit and vegetable products in the United States, Europe, and Japan. Both microbial and plant cell membranes are significantly altered following exposure to heat, HP, or PEF. Our research group sought to quantify the degree of damage to plant cell membranes that occurs as a result of exposure to heat, HP, or PEF, using the same analytical methods. In order to evaluate whether new advanced processing methods are superior to traditional thermal processing methods, it is necessary to compare them. In this review, we describe the existing state of knowledge related to effects of heat, HP, and PEF on both microbial and plant cells. The importance and relevance of compartmentalization in plant cells as it relates to fruit and vegetable quality is described and various methods for quantification of plant cell membrane integrity are discussed. These include electrolyte leakage, cell viability, and proton nuclear magnetic resonance (1H-NMR). PMID:20492210

  19. Energy Efficiency Improvement and Cost Saving Opportunities for the Fruit and Vegetable Processing Industry. An ENERGY STAR Guide for Energy and Plant Managers

    SciTech Connect

    Masanet, Eric; Masanet, Eric; Worrell, Ernst; Graus, Wina; Galitsky, Christina

    2008-01-01

    The U.S. fruit and vegetable processing industry--defined in this Energy Guide as facilities engaged in the canning, freezing, and drying or dehydrating of fruits and vegetables--consumes over $800 million worth of purchased fuels and electricity per year. Energy efficiency improvement isan important way to reduce these costs and to increase predictable earnings, especially in times of high energy price volatility. There are a variety of opportunities available at individual plants in the U.S. fruit and vegetable processing industry to reduce energy consumption in a cost-effective manner. This Energy Guide discusses energy efficiency practices and energy-efficient technologies that can be implemented at the component, process, facility, and organizational levels. A discussion of the trends, structure, and energy consumption characteristics of the U.S. fruit and vegetable processing industry is provided along with a description of the major process technologies used within the industry. Next, a wide variety of energy efficiency measures applicable to fruit and vegetable processing plants are described. Many measure descriptions include expected savings in energy and energy-related costs, based on case study data from real-world applications in fruit and vegetable processing facilities and related industries worldwide. Typical measure payback periods and references to further information in the technical literature are also provided, when available. Given the importance of water in fruit and vegetable processing, a summary of basic, proven measures for improving plant-level water efficiency are also provided. The information in this Energy Guide is intended to help energy and plant managers in the U.S. fruit and vegetable processing industry reduce energy and water consumption in a cost-effective manner while maintaining the quality of products manufactured. Further research on the economics of all measures--as well as on their applicability to different production

  20. Effect of hydrothermal processing on total polyphenolics and antioxidant potential of underutilized leafy vegetables, Boerhaavia diffusa and Portulaca oleracea

    PubMed Central

    Nagarani, Gunasekaran; Abirami, Arumugam; Nikitha, Prasad; Siddhuraju, Perumal

    2014-01-01

    Objective To investigate the effect of different processing methods on antioxidant properties of acetone extract of aerial parts from Boerhaavia diffusa and Portulaca oleracea. Methods The total phenolic and flavonoid contents were determined by Folin-Ciocalteau and aluminum chloride method, respectively. FRAP, metal chelating activity, DPPH, ABTS, nitric oxide, hydroxyl and superoxide radical scavenging activities, carotene/linoleic acid bleaching activity were used for the determination of antioxidant capacity. Results The total phenolics in Boerhaavia diffusa (82.79-162.80 mg GAE/g extract) were found to be higher when compared to that of Portulaca oleracea (22.94-10.02 mg GAE/g extract). Hydrothermal processing enhanced the level of inhibition on synthetic radicals such as DPPH (3 439-309 549 mmol TE/g extract) and ABTS (17 808-53 818 mmol TE/g extract) as well as biologically relevant radicals such as superoxide anion (70%-90%) and nitric oxide (49%-57%). In addition, boiling of the vegetables were found to be maximum capacity of FRAP (6 404.95 mmol Fe (II)/g extract) and metal chelating activity (1.53 mg EDTA/g extract) than the respective raw samples. Conclusions The present investigation suggests that the processing enhance the functionality and improves the availability of bioactive substances of these vegetables. In addition, they also exhibited more potent antioxidant activity. Therefore these natural weeds from the crop land ecosystem could be suggested as cost effective indigenous green vegetables for human diet and potential feed resources for animals. Further extensive studies on role and importance of those weeds in sustaining the agro biodiversity are also needed. PMID:25183131

  1. Inventories of Delaware's coastal vegetation and land-use utilizing digital processing of ERTS-1 imagery

    NASA Technical Reports Server (NTRS)

    Klemas, V.; Bartlett, D.; Rogers, R.; Reed, L.

    1974-01-01

    Digital analysis of ERTS-1 imagery was used in an attempt to map and inventory the significant ecological communities of Delaware's coastal zone. Eight vegetation and land use discrimination classes were selected: (1) phragmites communis (Giant Reed grass); (2) spartina alterniflora (Salt marsh cord grass); (3) spartina patens (Salt marsh hay); (4) shallow water and exposed mud; (5) deep water (2 meters); (6) forest; (7) agriculture; and (8) exposed sand and concrete. Canonical analysis showed that classification accuracy was quite good with spartina alterniflora, exposed sand-concrete, and forested land - all discriminated with between 94% and 100% accuracy. The shallow water-mud and deep water categories were classified with accuracies of 88% and 93% respectively. Phragmites communis showed a classification accuracy of 83% with all confusion occurring with spartina patens which may be due to use of mixed stands of these species as training sets. Discrimination of spartina patens was very poor (accuracy 52%).

  2. Effects of future climate change, CO2 enrichment, and vegetation structure variation on hydrological processes in China

    USGS Publications Warehouse

    Zhu, Qiuan; Jiang, Hong; Peng, Changhui; Liu, Jinxun; Fang, Xiuqin; Wei, Xiaohua; Liu, Shirong; Zhou, Guomo

    2012-01-01

    Investigating the relationship between factors (climate change, atmospheric CO2 concentrations enrichment, and vegetation structure) and hydrological processes is important for understanding and predicting the interaction between the hydrosphere and biosphere. The Integrated Biosphere Simulator (IBIS) was used to evaluate the effects of climate change, rising CO2, and vegetation structure on hydrological processes in China at the end of the 21st century. Seven simulations were implemented using the assemblage of the IPCC climate and CO2 concentration scenarios, SRES A2 and SRES B1. Analysis results suggest that (1) climate change will have increasing effects on runoff, evapotranspiration (ET), transpiration (T), and transpiration ratio (transpiration/evapotranspiration, T/E) in most hydrological regions of China except in the southernmost regions; (2) elevated CO2 concentrations will have increasing effects on runoff at the national scale, but at the hydrological region scale, the physiology effects induced by elevated CO2 concentration will depend on the vegetation types, climate conditions, and geographical background information with noticeable decreasing effects shown in the arid Inland region of China; (3) leaf area index (LAI) compensation effect and stomatal closure effect are the dominant factors on runoff in the arid Inland region and southern moist hydrological regions, respectively; (4) the magnitudes of climate change (especially the changing precipitation pattern) effects on the water cycle are much larger than those of the elevated CO2 concentration effects; however, increasing CO2 concentration will be one of the most important modifiers to the water cycle; (5) the water resource condition will be improved in northern China but depressed in southernmost China under the IPCC climate change scenarios, SRES A2 and SRES B1.

  3. Concentration-dependent NH 3 deposition processes for mixed moorland semi-natural vegetation

    NASA Astrophysics Data System (ADS)

    Jones, M. R.; Leith, I. D.; Fowler, D.; Raven, J. A.; Sutton, M. A.; Nemitz, E.; Cape, J. N.; Sheppard, L. J.; Smith, R. I.; Theobald, M. R.

    Dry deposition modelling typically assumes that canopy resistance ( Rc) is independent of ammonia (NH 3) concentration. An innovative flux chamber system was used to provide accurate continuous measurements of NH 3 deposition to a moorland composed of a mixture of Calluna vulgaris (L.) Hull, Eriophorum vaginatum L. and Sphagnum spp. Ammonia was applied at a wide range of concentrations (1-100 μg m -3). The physical and environmental properties and the testing of the chamber are described, as well as results for the moorland vegetation using the 'canopy resistance' and 'canopy compensation point' interpretations of the data. Results for moorland plant species demonstrate that NH 3 concentration directly affects the rate of NH 3 deposition to the vegetation canopy, with Rc and cuticular resistance ( Rw) increasing with increasing NH 3 concentrations. Differences in Rc were found between night and day: during the night Rc increases from 17 s m -1 at 10 μg m -3 to 95 s m -1 at 80 μg m -3, whereas during the day Rc increases from 17 s m -1 at 10 μg m -3 to 48 s m -1 at 80 μg m -3. The lower resistance during the day is caused by the stomata being open and available as a deposition route to the plant. Rw increased with increasing NH 3 concentrations and was not significantly different between day and night (at 80 μg m -3 NH 3 day Rw=88 s m -1 and night Rw=95 s m -1). The results demonstrate that assessments using fixed Rc will over-estimate NH 3 deposition at high concentrations (over ˜15 μg m -3).

  4. Gully erosion processes impacted by vegetation on gully beds based on an in situ scouring experiment in a Dry-hot Valley of Southwest China

    NASA Astrophysics Data System (ADS)

    Dong, Yifan; Xiong, Donghong; Su, Zhengan

    2015-04-01

    Vegetation can protect soil from water erosion. Some previous researches on the subjects of vegetation and gully erosion were mainly focused on the topography changes cause by vegetation and the conservation effects and techniques. While the mechanics of vegetation effects on the hydraulic processes of gully bed to influence the erosion processes were still not very clear. In this study, an in situ scouring experiment was conducted 11 times assuming a consistent flow condition (7 times with a flow discharge of 83.3L/min and 4 times with a flow discharge of 166.7 L/min on five gully head plots with gully bed lengths of 20 m, which were constructed with similar initial topography (height of the headcuts were 0.5m, the slope of gully beds were from 18.2% to 19.1%) and same soil type (Dry red soil which classified as Rhodoxeralfs in USDA Soil Taxonomy ). Five vegetation condition levels were set on gully bed (the same vegetation density and different lengths of the vegetation sites as 0 m, 4m, 8m, 12m and 16m). Each scouring last 1h and the flow rate, flow depth and flow width were recorded every 10 minutes, after each scouring the topography changes were measured by RTK GPS. The total gully bed erosion volume (TEV) exhibited a significant exponentially decreasing relationship with increasing length of the vegetation sites (VL) due to the similar relationship between the VL and the runoff erosion capacity. The hydrodynamic parameters in the vegetation sites were clearly lower than those in bare sites and caused the average TEV of the vegetation sites to be approximately 3.3 times lower than that of the bare gully bed. However, the vegetation protection efficiency did not increase as the length of the vegetation sites increased. The hydrodynamics of the bare site sections showed a good relationship with TEV, while in the vegetation sites, the relationship was quite weak, indicating that hydraulics conditions were not the main factors influencing gully bed erosion in the

  5. Process-based modeling of vegetation dynamics, snow, evapotranspiration and soil moisture patterns in an alpine catchment

    NASA Astrophysics Data System (ADS)

    Bertoldi, Giacomo; Della Chiesa, Stefano; Engel, Michael; Niedrist, Georg; Brenner, Johannes G.; Endrizzi, Stefano; Dall'Amico, Matteo; Cordano, Emanuele; Tappeiner, Ulrike; Rigon, Riccardo

    2014-05-01

    Mountain regions are particularly sensitive to climate change and at the same time they represent a key water resource not only locally but as well for lowland areas. Because of the complexity of mountain landscapes and the high climatic variability at a local scale, detailed quantification of key water budget components as snow cover, soil moisture and groundwater recharge is required. Therefore, there is a strong need to improve the capability of hydrological models to identify patterns in complex terrain (i.e. when variability of spatial characteristics counts), and to quantify changes of the water cycle components explicitly, considering interactions and feedbacks with climate and vegetation. Process-based hydrological models represent promising tools for addressing those needs. However, even if their inherent complexity sometimes limits their applicability for operational purpose, they offer great potential in terms of tools to test hypotheses, which can be verified in the field. GEOtop is a hydrological model that calculates the energy and mass exchanges between soil, vegetation, and atmosphere, accounting for land cover, water redistribution, snow processes, glacier mass budget and the effects of complex terrain and thus is one of the few models that was built with this complexity in mind. Recently, it has also been coupled with a dynamic vegetation model in order to simulate alpine grassland ecosystems. In this contribution, we want to present an application of the GEOtop model in simulating above ground biomass (Bag) production, evapotranspiration (ET), soil moisture (SM) and snow water equivalent (SWE) patterns for a catchment of about 100 km2, located in the Venosta/Vinschgau valley in the European Alps. Despite the Alps are one of the 'water towers of Europe', water scarcity issues can affect the region where the model is applied, and an intensive hydrological and ecological monitoring activity with ground observations and remote-sensing products has

  6. Characterization of the aroma of a meatlike process flavoring from soybean-based enzyme-hydrolyzed vegetable protein.

    PubMed

    Wu, Yi-Fang G; Cadwallader, Keith R

    2002-05-01

    Defatted soybean meal was converted into enzyme-hydrolyzed vegetable protein (E-HVP) using the proteolytic enzyme Flavorzyme. Total free amino acids increased by 40-fold after enzyme hydrolysis, with leucine being the most abundant, followed by phenylalanine, lysine, glutamine/glutamic acid, and alanine. Volatile components from a meatlike process flavoring made from E-HVP were isolated by direct solvent extraction (DSE)-high vacuum transfer (HVT), dynamic headspace sampling and static headspace sampling and analyzed by gas chromatography (GC)-mass spectrometry and GC-olfactometry. Aroma extract dilution analysis was used to establish a flavor dilution chromatogram of the DSE-HVT extract. Results of these complementary techniques indicated the importance of odorants of high (hydrogen sulfide and methanethiol), intermediate (2-methyl-3-furanthiol, 3-mercapto-2-pentanone, 2-furanmethanethiol, and 3-(methylthiol)propanal) and low volatility (maltol and Furaneol) in the overall aroma of the meatlike process flavoring. PMID:11982417

  7. [Toxicological evaluation of pesticide and chemical residues in control of biological processes in vegetables under glass and plastics].

    PubMed

    Goedicke, H J

    1988-01-01

    The cultivation of vegetables under glass and plastics is one of the most intensive application fields of pesticides and chemicals for regulation of biological processes. Therefore it may potentially occur a relatively high residues contamination of the crops. The author reveals in a survey the residue situation of usual insecticides, acaricides, fungicides, and chemicals for regulation of biological processes on tomatoes, cucumbers, and lettuce in comparison with the maximum residue limit after cold fogging application. The residues of benomyl, carbendazim, and ethylen-bis-dithiocarbamate are detailed discussed in the light of the latest toxicological findings. The results the residues of 11 agents on the crops show that after the corresponding preharvest interval the residues constitute 1.7-78% of the maximum residue limit. The conclusion is drawn that the cold fogging application of the agents under glass and plastics does not result in food hygienic toxicological problems. PMID:3068546

  8. Toxicological evaluation of vegetable oils and biodiesel in soil during the biodegradation process

    PubMed Central

    Tamada, Ivo S.; Montagnolli, Renato N.; Lopes, Paulo R. M.; Bidoia, Ederio D.

    2012-01-01

    Vegetable oils and their derivatives, like biodiesel, are used extensively throughout the world, thus posing an environmental risk when disposed. Toxicity testing using test organisms shows how these residues affect ecosystems. Toxicity tests using earthworms (Eisenia foetida) are widespread because they are a practical resource for analyzing terrestrial organisms. For phytotoxicological analysis, we used seeds of arugula (Eruca sativa) and lettuce (Lactuca sativa) to analyze the germination of seeds in contaminated soil samples. The toxicological experiment was conducted with four different periods of biodegradation in soil: zero days, 60 days, 120 days and 180 days. The studied contaminants were soybean oil (new and used) and biodiesel (B100). An evaluation of the germination of both seeds showed an increased toxicity for all contaminants as the biodegradation occurred, biodiesel being the most toxic among the contaminants. On the other hand, for the tests using earthworms, the biodiesel was the only contaminant that proved to be toxic. Therefore, the higher toxicity of the sample containing these hydrocarbons over time can be attributed to the secondary compounds formed by microbial action. Thus, we conclude that the biodegradation in soil of the studied compounds requires longer periods for the sample toxicity to be decreased with the action of microorganisms. PMID:24031989

  9. Role of Boreal Vegetation in Controlling Ecosystem Processes and Feedbacks to Climate

    NASA Technical Reports Server (NTRS)

    Chapin, F. S., III; Hooper, D. U.; Hobbie, S. E.; Verville, J. H.

    1997-01-01

    In the field, dark respiration rates are greatest in cores from more northerly locations. This is due in part to greater amounts of dwarf shrub biomass in the more northerly cores, but also to differences in soil organic matter quality. Laboratory incubations of these soils under common conditions show some evidence for greater pools of available carbon in soils from more northerly tundra sites, although the most northerly site does not fit this pattern for reasons which are unclear at this time. While field measurements of cores transplanted among different vegetation types at the same location (Toolik Lake) show relatively small differences in whole ecosystem carbon flux, laboratory incubation of these same soils shows that there are large differences in soil respiration rates under common conditions. This is presumably due to differences in organic matter quality. Microenvironmental site factors (temperature, soil moisture, degree of anaerobiosis, etc.) may be responsible for evening out these differences in the field. These site factors, which differ with slope, aspect, and drainage within a given location along the latitudinal gradient, appear to exert at least as strong a control over carbon fluxes as do macroclimatic factors among sites across the latitudinal gradient. While our field measurements indicate that, in the short term, warming will tend to increase ecosystem losses Of CO2 via respiration more than they will increase plant gross assimilation, the degree to which different topographically-defined plant communities will respond is likely to vary.

  10. Integrating peatlands and permafrost into a dynamic global vegetation model: 1. Evaluation and sensitivity of physical land surface processes

    NASA Astrophysics Data System (ADS)

    Wania, R.; Ross, I.; Prentice, I. C.

    2009-09-01

    Northern peatlands and permafrost soils are associated with large carbon stocks. Rising temperatures are likely to affect the carbon balance in high-latitude ecosystems, but to what degree is uncertain. We have enhanced the Lund-Potsdam-Jena (LPJ) dynamic global vegetation model by introducing processes necessary to simulate permafrost dynamics, peatland hydrology, and peatland vegetation. The new version, LPJ-WHy v1.2, was used to study soil temperature, active layer depth, permafrost distribution, and water table position. Modeled soil temperatures agreed well with observations, apart from a Siberian site where the soil is insulated by an extensive shrub layer. Water table positions were generally in the range of observations, with some exceptions. Simulated active layer depth showed a mean absolute error of 44 cm when compared to observations, but the error was reduced to 25 cm when the soil type for seven sites was manually corrected to mirror local conditions. A sensitivity test, in which temperature and precipitation were varied independently, showed that soil temperatures and active layer depths increased more under higher temperatures when precipitation was increased at the same time. The sensitivity experiment suggested persisting wet conditions in peatlands even under temperature increases of up to 9°C as long as annual precipitation is allowed to increase with temperature to the extent indicated by climate model experiments.

  11. Global Validation of a Process-Based Model on Vegetation Gross Primary Production Using Eddy Covariance Observations

    PubMed Central

    Liu, Dan; Cai, Wenwen; Xia, Jiangzhou; Dong, Wenjie; Zhou, Guangsheng; Chen, Yang; Zhang, Haicheng; Yuan, Wenping

    2014-01-01

    Gross Primary Production (GPP) is the largest flux in the global carbon cycle. However, large uncertainties in current global estimations persist. In this study, we examined the performance of a process-based model (Integrated BIosphere Simulator, IBIS) at 62 eddy covariance sites around the world. Our results indicated that the IBIS model explained 60% of the observed variation in daily GPP at all validation sites. Comparison with a satellite-based vegetation model (Eddy Covariance-Light Use Efficiency, EC-LUE) revealed that the IBIS simulations yielded comparable GPP results as the EC-LUE model. Global mean GPP estimated by the IBIS model was 107.50±1.37 Pg C year−1 (mean value ± standard deviation) across the vegetated area for the period 2000–2006, consistent with the results of the EC-LUE model (109.39±1.48 Pg C year−1). To evaluate the uncertainty introduced by the parameter Vcmax, which represents the maximum photosynthetic capacity, we inversed Vcmax using Markov Chain-Monte Carlo (MCMC) procedures. Using the inversed Vcmax values, the simulated global GPP increased by 16.5 Pg C year−1, indicating that IBIS model is sensitive to Vcmax, and large uncertainty exists in model parameterization. PMID:25375227

  12. Evaluation of the assimilation of As by vegetables in contaminated soils submitted to a remediation process

    NASA Astrophysics Data System (ADS)

    Pérez-Sirvent, Carmen; Martinez Sanchez, Maria Jose; Agudo, Ines; Belen Martinez, Lucia; Bech, Jaume

    2016-04-01

    A greenhouse trial was carried out to evaluate the assimilation of heavy metals by three types of plants (lettuce, onion and broccoli), different parts of which are destined for human and farm animals consumption (leaves, roots, fruits). The experiments were carried out to check the validity of the use of calcareous materials to recover soils contaminated with heavy metals. The aim of this work was to apply a technology for decontamination to ensure that As do not enter into the trophic chain at risky levels and analyze and to assess the risk pre and post operational of the different treatments proposed. The materials used was a soils to be remediated (mining soils) and the materials used for remediation were lime filler and Construction and Demolition Waste (CDW). The plants were cultivated in greenhouse with several types of soil. Five experiments were used, namely, Tc (contaminated soil), T1 (uncontaminated soil (blank soil)), T2 (50% T1 + 50% Tc), T3 (Tc + (25%) lime residues coming from quarries) and T4 (Tc + (25%) residues coming from demolition and construction activities). The entire project involves twenty experiments which were prepared from soils highly contaminated mixed with two types of calcareous materials. The total As content of the soils samples, rhizosphere and vegetable samples, were measured and the translocation factor (TF), which is defined as the ratio of metal concentration in the leaves or shoots to the roots, and the Bioconcentration factor (BCF), which is defined as the ratio of metal concentration in the roots to that in soil were calculated. The use of CDR is shown to be a suitable way for remediating soils contaminated by metals. The methodology permits a revalorization of CDW.

  13. Multiscale Precipitation Processes Over Mountain Terrain - Landform and Vegetation Controls of Microphysics and Convection in Complex Terrain

    NASA Astrophysics Data System (ADS)

    Barros, A. P.; Wilson, A. M.; Sun, X.; Duan, Y.

    2015-12-01

    Recent precipitation observations in mountainous regions do not exhibit the classical orographic enhancement with elevation, especially where fog and multi-layer clouds are persistent. The role of landform in modulating moisture convergence patterns and constraining the thermodynamic environment that supports the development of complex vertical structures of clouds and precipitation is discussed first using observations and model results from the IPHEx (Integrated Precipitation and Hydrology Experiment) field campaign in the Southern Appalachian Mountains (SAM). Analysis of the complex spatial heterogeneity of precipitation microphysics in the SAM suggests that seeder-feeder interactions (SFI) among stratiform precipitation, low level clouds (LLC), and fog play a governing role on the diurnal and seasonal cycles of observed precipitation regimes. Further, in the absence of synoptic-scale forcing, results suggest that evapotranspiration makes a significant contribution to the moisture budget in the lower atmosphere, creating super-saturation conditions favorable to CCN activation, LLC formation, and light rainfall. To investigate the role of evapotranspiration on the diurnal cycle of mountain precipitation further, range-scale modeling studies were conducted in the Central Andes. Specifically, high resolution WRF simulations for realistic and quasi-idealized ET withdrawal case-studies show that evapotranspiration fluxes modulated by landform govern convective activity in the lower troposphere, including cloud formation and precipitation processes that account for daily precipitation amounts as high as 50-70% depending on synoptic conditions and season. These studies suggest multiscale vegetation controls of orographic precipitation processes via atmospheric instability on the one hand, and low level super-saturation and local microphysics on the other. A conceptual model of multiscale interactions among vegetation, landform and moist processes over complex

  14. The effect of vegetation type and fire on permafrost thaw: An empirical test of a process based model

    NASA Astrophysics Data System (ADS)

    Thierry, Aaron; Estop-Aragones, Cristian; Fisher, James; Hartley, Iain; Murton, Julian; Phoenix, Gareth; Street, Lorna; Williams, Mathew

    2015-04-01

    As conditions become more favourable for plant growth in the high latitudes, most models predict that these areas will take up more carbon during the 21st century. However, vast stores of carbon are frozen in boreal and arctic permafrost, and warming may result in some of this carbon being released to the atmosphere. The recent inclusion of permafrost thaw in large-scale model simulations has suggested that the permafrost feedback could potentially substantially reduce the predicted global net uptake of carbon by terrestrial ecosystems, with major implications for the rate of climate change. However, large uncertainties remain in predicting rates of permafrost thaw and in determining the impacts of thaw in contrasting ecosystems, with many of the key processes missing from carbon-climate models. The role that different plant communities play in insulating soils and protecting permafrost is poorly quantified, with key groups such as mosses absent in many models. But it is thought that they may play a key role in determining permafrost resilience. In order to test the importance of these ecological processes we use a new specially acquired dataset from sites in the Canadian arctic to develop, parameterise and evaluate a detailed process-based model of vegetation-soil-permafrost interactions which includes an insulating moss understory. We tested the sensitivity of modelled active layer depth to a series of factors linked to fire disturbance, which is common in boreal permafrost areas. We show how simulations of active layer depth (ALD) respond to removals of (i) vascular vegetation, (ii) moss cover, and (iii) organic soil layers. We compare model responses to observed patterns from Canada. We also describe the sensitivity of our modelled ALD to changes in temperature and precipitation. We found that four parameters controlled most of the sensitivity in the modelled ALD, linked to conductivity of organic soils and mosses.

  15. Simulating boreal forest carbon dynamics after stand-replacing fire disturbance: insights from a global process-based vegetation model

    NASA Astrophysics Data System (ADS)

    Yue, C.; Ciais, P.; Luyssaert, S.; Cadule, P.; Harden, J.; Randerson, J.; Bellassen, V.; Wang, T.; Piao, S. L.; Poulter, B.; Viovy, N.

    2013-12-01

    Stand-replacing fires are the dominant fire type in North American boreal forests. They leave a historical legacy of a mosaic landscape of different aged forest cohorts. This forest age dynamics must be included in vegetation models to accurately quantify the role of fire in the historical and current regional forest carbon balance. The present study adapted the global process-based vegetation model ORCHIDEE to simulate the CO2 emissions from boreal forest fire and the subsequent recovery after a stand-replacing fire; the model represents postfire new cohort establishment, forest stand structure and the self-thinning process. Simulation results are evaluated against observations of three clusters of postfire forest chronosequences in Canada and Alaska. The variables evaluated include: fire carbon emissions, CO2 fluxes (gross primary production, total ecosystem respiration and net ecosystem exchange), leaf area index, and biometric measurements (aboveground biomass carbon, forest floor carbon, woody debris carbon, stand individual density, stand basal area, and mean diameter at breast height). When forced by local climate and the atmospheric CO2 history at each chronosequence site, the model simulations generally match the observed CO2 fluxes and carbon stock data well, with model-measurement mean square root of deviation comparable with the measurement accuracy (for CO2 flux ~100 g C m-2 yr-1, for biomass carbon ~1000 g C m-2 and for soil carbon ~2000 g C m-2). We find that the current postfire forest carbon sink at the evaluation sites, as observed by chronosequence methods, is mainly due to a combination of historical CO2 increase and forest succession. Climate change and variability during this period offsets some of these expected carbon gains. The negative impacts of climate were a likely consequence of increasing water stress caused by significant temperature increases that were not matched by concurrent increases in precipitation. Our simulation results

  16. Simulating boreal forest carbon dynamics after stand-replacing fire disturbance: insights from a global process-based vegetation model

    USGS Publications Warehouse

    Yue, C.; Ciais, P.; Luyssaert, S.; Cadule, P.; Harden, J.; Randerson, J.; Bellassen, V.; Wang, T.; Piao, S.L.; Poulter, B.; Viovy, N.

    2013-01-01

    Stand-replacing fires are the dominant fire type in North American boreal forests. They leave a historical legacy of a mosaic landscape of different aged forest cohorts. This forest age dynamics must be included in vegetation models to accurately quantify the role of fire in the historical and current regional forest carbon balance. The present study adapted the global process-based vegetation model ORCHIDEE to simulate the CO2 emissions from boreal forest fire and the subsequent recovery after a stand-replacing fire; the model represents postfire new cohort establishment, forest stand structure and the self-thinning process. Simulation results are evaluated against observations of three clusters of postfire forest chronosequences in Canada and Alaska. The variables evaluated include: fire carbon emissions, CO2 fluxes (gross primary production, total ecosystem respiration and net ecosystem exchange), leaf area index, and biometric measurements (aboveground biomass carbon, forest floor carbon, woody debris carbon, stand individual density, stand basal area, and mean diameter at breast height). When forced by local climate and the atmospheric CO2 history at each chronosequence site, the model simulations generally match the observed CO2 fluxes and carbon stock data well, with model-measurement mean square root of deviation comparable with the measurement accuracy (for CO2 flux ~100 g C m−2 yr−1, for biomass carbon ~1000 g C m−2 and for soil carbon ~2000 g C m−2). We find that the current postfire forest carbon sink at the evaluation sites, as observed by chronosequence methods, is mainly due to a combination of historical CO2 increase and forest succession. Climate change and variability during this period offsets some of these expected carbon gains. The negative impacts of climate were a likely consequence of increasing water stress caused by significant temperature increases that were not matched by concurrent increases in precipitation. Our simulation

  17. Quality-related enzymes in fruit and vegetable products: effects of novel food processing technologies, part 1: high-pressure processing.

    PubMed

    Terefe, Netsanet Shiferaw; Buckow, Roman; Versteeg, Cornelis

    2014-01-01

    The activity of endogenous deteriorative enzymes together with microbial growth (with associated enzymatic activity) and/or other non-enzymatic (usually oxidative) reactions considerably shorten the shelf life of fruits and vegetable products. Thermal processing is commonly used by the food industry for enzyme and microbial inactivation and is generally effective in this regard. However, thermal processing may cause undesirable changes in product's sensory as well as nutritional attributes. Over the last 20 years, there has been a great deal of interest shown by both the food industry and academia in exploring alternative food processing technologies that use minimal heat and/or preservatives. One of the technologies that have been investigated in this context is high-pressure processing (HPP). This review deals with HPP focusing on its effectiveness for controlling quality-degrading enzymes in horticultural products. The scientific literature on the effects of HPP on plant enzymes, mechanism of action, and intrinsic and extrinsic factors that influence the effectiveness of HPP for controlling plant enzymes is critically reviewed. HPP inactivates vegetative microbial cells at ambient temperature conditions, resulting in a very high retention of the nutritional and sensory characteristics of the fresh product. Enzymes such as polyphenol oxidase (PPO), peroxidase (POD), and pectin methylesterase (PME) are highly resistant to HPP and are at most partially inactivated under commercially feasible conditions, although their sensitivity towards pressure depends on their origin as well as their environment. Polygalacturonase (PG) and lipoxygenase (LOX) on the other hand are relatively more pressure sensitive and can be substantially inactivated by HPP at commercially feasible conditions. The retention and activation of enzymes such as PME by HPP can be beneficially used for improving the texture and other quality attributes of processed horticultural products as well as

  18. Experiments in water-macrophyte systems to uncover the dynamics of pesticide mitigation processes in vegetated surface waters/streams.

    PubMed

    Stang, Christoph; Bakanov, Nikita; Schulz, Ralf

    2016-01-01

    Knowledge on the dynamics and the durability of the processes governing the mitigation of pesticide loads by aquatic vegetation in vegetated streams, which are characterized by dynamic discharge regimes and short chemical residence times, is scarce. In a static long-term experiment (48 h), the dissipation of five pesticides from the aqueous phase followed a biphasic pattern in the presence of aquatic macrophytes. A dynamic concentration decrease driven by sorption to the macrophytes ranged from 8.3 to 60.4% for isoproturon and bifenox, respectively, within the first 2 h of exposure. While the aqueous concentrations of imidacloprid, isoproturon, and tebufenozide remained constant thereafter, the continuous but decelerated concentration decrease of difenoconazole and bifenox in the water-macrophyte systems used here was assumed to be attributed to macrophyte-induced degradation processes. In addition, a semi-static short-term experiment was conducted, where macrophytes were transferred to uncontaminated medium after 2 h of exposure to simulate a transient pesticide peak. In the first part of the experiment, adsorption to macrophytes resulted in partitioning coefficients (logK D_Adsorp) ranging from 0.2 for imidacloprid to 2.2 for bifenox. One hour after the macrophytes were transferred to the uncontaminated medium, desorption of the compounds from the macrophytes resulted in a new phase equilibrium and K D_Desorp values of 1.46 for difenoconazole and 1.95 for bifenox were determined. A correlation analysis revealed the best match between the compound affinity to adsorb to macrophytes (expressed as K D_Adsorp) and their soil organic carbon-water partitioning coefficient (K OC) compared to their octanol-water partitioning coefficient (K OW) or a mathematically derived partitioning coefficient. PMID:26335524

  19. Application of the microbiological method DEFT/APC to detect minimally processed vegetables treated with gamma radiation

    NASA Astrophysics Data System (ADS)

    Araújo, M. M.; Duarte, R. C.; Silva, P. V.; Marchioni, E.; Villavicencio, A. L. C. H.

    2009-07-01

    Marketing of minimally processed vegetables (MPV) are gaining impetus due to its convenience, freshness and apparent health effect. However, minimal processing does not reduce pathogenic microorganisms to safe levels. Food irradiation is used to extend the shelf life and to inactivate food-borne pathogens. In combination with minimal processing it could improve safety and quality of MPV. A microbiological screening method based on the use of direct epifluorescent filter technique (DEFT) and aerobic plate count (APC) has been established for the detection of irradiated foodstuffs. The aim of this study was to evaluate the applicability of this technique in detecting MPV irradiation. Samples from retail markets were irradiated with 0.5 and 1.0 kGy using a 60Co facility. In general, with a dose increment, DEFT counts remained similar independent of the irradiation while APC counts decreased gradually. The difference of the two counts gradually increased with dose increment in all samples. It could be suggested that a DEFT/APC difference over 2.0 log would be a criteria to judge if a MPV was treated by irradiation. The DEFT/APC method could be used satisfactorily as a screening method for indicating irradiation processing.

  20. Data service platform for MODIS Vegetation Indices time series processing at BOKU Vienna: current status and future perspectives

    NASA Astrophysics Data System (ADS)

    Vuolo, Francesco; Mattiuzzi, Matteo; Klisch, Anja; Atzberger, Clement

    2012-10-01

    The aim of this paper is to present a freely available data service platform (http://ivfl-info.boku.ac.at/) for executing preprocessing operations (such as data smoothing, spatial and temporal sub-setting, mosaicking and reprojection) of time series of Moderate Resolution Imaging Spectroradiometer (MODIS) vegetation indices (NDVI and EVI) on request. The web-application is based on the integration of various software and hardware components: a web-interface and a MySQL database are used to collect and store user's requests. A server-side application schedules the user's requests and delivers the results. The core of the processing system is based on the "MODIS" package developed in R, which provides MODIS data collection and pre-processing capabilities. Smoothed and gap-filled data sets are derived using the state-ofthe- art Whittaker filter implemented in Matlab. After the processing, data are delivered directly via ftp access. An analysis of the performance of the web-application, along with processing capacity is presented. Results are discussed, in particular in view of an operative platform for real time filtering, phenology and land cover mapping.

  1. Inactivation kinetics and photoreactivation of vegetable oxidative enzymes after combined UV-C processing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The inactivation kinetics of lipoxygenase (LOX), peroxidase (POD) and polyphenoloxidase (PPO) in phosphate buffer (pH 4.0 and 7.0) treated by combined thermal (25-65 C) and UV-C (1-10 min) processes were fitted using a traditional first-order kinetics model and the Weibull distribution function. For...

  2. Process of change for increasing fruit and vegetable consumption among economically disadvantaged African American adolescents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study sought to identify Transtheoretical Model processes of change associated with consumption of = 5 daily servings of FVs in a sample of economically disadvantaged African American adolescents (N = 549; mean (SD) age = 12.44 (.99) years; 61% female; 15% African American Hispanic). Participan...

  3. Interactions between river channel processes and riparian vegetation - an example from the Lužnice River, Czech Republic

    NASA Astrophysics Data System (ADS)

    Krejci, Lukas; Macka, Zdenek

    2010-05-01

    Riparian vegetation responds to hydrogemorphic processes and environmental changes and also controls these processes. Our study focuses on the interactions between woody riparian vegetation (live and dead trees) and river channel morphology on the example of three 1 km long reaches of the Lužnice River in southern Czech Republic. Here, we propose that despite spatial proximity, identical hydrological and sedimentological controls, three river reaches have different geomorphology due to varying character of riparian woody vegetation and different character and abundance of large in-stream wood (LW). Upstream, middle and downstream reaches vary markedly in channel dimensions (width, depth) and the present day rate of lateral erosion. Three reaches also show the different in-stream wood loads which are dependent mainly on the character of the riparian vegetation, and on the lateral activity of the channel. The highest wood load was recorded at the downstream reach with 102,162 m3/ha, the lowest at the middle reach 37,041 m3/ha, the upstream reach has load 81,370 m3/ha. Upper reach woody vegetation is the mixture of willow, alder, chokecherry and oak. The reach is only slightly sinuous with the moderate rate of incision and lateral erosion. The channel width and depth are 13 m and 2,1 m respectively, the mean cross section area is 27,3 m2. Erosion in the reach is slightly enhanced by the river training works upstream (canalisation, weir construction). Middle reach woody vegetation mostly consist of willow. Tree-tops often incline into the channel, thus, dissipating effectively the energy of the river flow. The reach is moderately sinuous and rather laterally stable. The channel width and depth are 10 m and 2,5 m respectively, the mean cross section area is 25 m2. The reach approximates the natural condition of the pristine river. The impact of river training works is minor only with the road bridge upstream. This reach in the most natural condition shows the lowest in

  4. Application of poultry processing industry waste: a strategy for vegetation growth in degraded soil.

    PubMed

    do Nascimento, Carla Danielle Vasconcelos; Pontes Filho, Roberto Albuquerque; Artur, Adriana Guirado; Costa, Mirian Cristina Gomes

    2015-02-01

    The disposal of poultry processing industry waste into the environment without proper care, can cause contamination. Agricultural monitored application is an alternative for disposal, considering its high amount of organic matter and its potential as a soil fertilizer. This study aimed to evaluate the potential of poultry processing industry waste to improve the conditions of a degraded soil from a desertification hotspot, contributing to leguminous tree seedlings growth. The study was carried out under greenhouse conditions in a randomized blocks design and a 4 × 2 factorial scheme with five replicates. The treatments featured four amounts of poultry processing industry waste (D1 = control 0 kg ha(-1); D2 = 1020.41 kg ha(-1); D3 = 2040.82 kg ha(-1); D4 = 4081.63 kg ha(-1)) and two leguminous tree species (Mimosa caesalpiniaefolia Benth and Leucaena leucocephala (Lam.) de Wit). The poultry processing industry waste was composed of poultry blood, grease, excrements and substances from the digestive system. Plant height, biomass production, plant nutrient accumulation and soil organic carbon were measured forty days after waste application. Leguminous tree seedlings growth was increased by waste amounts, especially M. caesalpiniaefolia Benth, with height increment of 29.5 cm for the waste amount of 1625 kg ha(-1), and L. leucocephala (Lam.) de Wit, with maximum height increment of 20 cm for the waste amount of 3814.3 kg ha(-1). M. caesalpiniaefolia Benth had greater initial growth, as well as greater biomass and nutrient accumulation compared with L. leucocephala (Lam.) de Wit. However, belowground biomass was similar between the evaluated species, resulting in higher root/shoot ratio for L. leucocephala (Lam.) de Wit. Soil organic carbon did not show significant response to waste amounts, but it did to leguminous tree seedlings growth, especially L. leucocephala (Lam.) de Wit. Poultry processing industry waste contributes to leguminous tree seedlings growth

  5. The role of vegetation covers on soil wetting processes at rainfall event scale in scattered tree woodland of Mediterranean climate

    NASA Astrophysics Data System (ADS)

    Lozano-Parra, Javier; Schnabel, Susanne; Ceballos-Barbancho, Antonio

    2015-10-01

    Soil water is recognized as the key factor that controls the organization and functioning of dryland ecosystems. However, in spite of its great importance in ecohydrological processes as well as in modelling applications, most of the studies focus on daily or longer timescales, while its dynamics at shorter timescales are very little known. The main objective of this work was to determine the role of vegetation covers (grassland and tree canopy) in the soil hydrological response using measurements with high temporal resolution in evergreen oak woodland with Mediterranean climate. For this, soil water content was measured with capacitive sensors installed in the soil profile at different depths registering continuously with a high time resolution. Three study areas were monitored for two and half hydrological years. Results obtained revealed that rainwater amounts reaching the soil may temporarily be modified by covers according to precipitation properties and antecedent conditions (from dry to wet) before the rain episode. Rainfall amounts triggering a positive soil hydrological response decreased as initial states became drier, being more accentuated below tree canopies. The frequency of re-wetting cycles and the antecedent states seem to be as important or even more than either the duration or the precipitation amount. Therefore, the role of vegetation was more decisive under drier environmental conditions, where events lower than 6 mm and 2 mm never caused soil hydrological response either below tree canopy or grassland, respectively. This is important because initial conditions were independent of seasonality and because more than half of all rainfall events registered amounts smaller than 5 mm. If changes on precipitation patterns turn out in drier conditions, the predominance of such situations could have important ecohydrological consequences in semiarid ecosystems.

  6. Effect of steaming, blanching, and high temperature/high pressure processing on the amino Acid contents of commonly consumed korean vegetables and pulses.

    PubMed

    Kim, Su-Yeon; Kim, Bo-Min; Kim, Jung-Bong; Shanmugavelan, Poovan; Kim, Heon-Woong; Kim, So-Young; Kim, Se-Na; Cho, Young-Sook; Choi, Han-Seok; Park, Ki-Moon

    2014-09-01

    In the present report, the effects of blanching, steaming, and high temperature/high pressure processing (HTHP) on the amino acid contents of commonly consumed Korean root vegetables, leaf vegetables, and pulses were evaluated using an Automatic Amino Acid Analyzer. The total amino acid content of the samples tested was between 3.38 g/100 g dry weight (DW) and 21.32 g/100 g DW in raw vegetables and between 29.36 g/100 g DW and 30.55 g/100 g DW in raw pulses. With HTHP, we observed significant decreases in the lysine and arginine contents of vegetables and the lysine, arginine, and cysteine contents of pulses. Moreover, the amino acid contents of blanched vegetables and steamed pulses were more similar than the amino acid contents of the HTHP vegetables and HTHP pulses. Interestingly, lysine, arginine, and cysteine were more sensitive to HTHP than the other amino acids. Partial Least Squares-Discriminate Analyses were also performed to discriminate the clusters and patterns of amino acids. PMID:25320720

  7. Effect of Steaming, Blanching, and High Temperature/High Pressure Processing on the Amino Acid Contents of Commonly Consumed Korean Vegetables and Pulses

    PubMed Central

    Kim, Su-Yeon; Kim, Bo-Min; Kim, Jung-Bong; Shanmugavelan, Poovan; Kim, Heon-Woong; Kim, So-Young; Kim, Se-Na; Cho, Young-Sook; Choi, Han-Seok; Park, Ki-Moon

    2014-01-01

    In the present report, the effects of blanching, steaming, and high temperature/high pressure processing (HTHP) on the amino acid contents of commonly consumed Korean root vegetables, leaf vegetables, and pulses were evaluated using an Automatic Amino Acid Analyzer. The total amino acid content of the samples tested was between 3.38 g/100 g dry weight (DW) and 21.32 g/100 g DW in raw vegetables and between 29.36 g/100 g DW and 30.55 g/100 g DW in raw pulses. With HTHP, we observed significant decreases in the lysine and arginine contents of vegetables and the lysine, arginine, and cysteine contents of pulses. Moreover, the amino acid contents of blanched vegetables and steamed pulses were more similar than the amino acid contents of the HTHP vegetables and HTHP pulses. Interestingly, lysine, arginine, and cysteine were more sensitive to HTHP than the other amino acids. Partial Least Squares-Discriminate Analyses were also performed to discriminate the clusters and patterns of amino acids. PMID:25320720

  8. Evaluating North America Paleoclimate Simulations for 6 ka and 21 ka Using a Combination of Observed Paleovegetation Data and Process-Based Vegetation Model Simulations

    NASA Astrophysics Data System (ADS)

    Shafer, S. L.; Bartlein, P. J.

    2015-12-01

    Paleoclimate model simulations are often evaluated using observed paleovegetation data (e.g., pollen and plant macrofossils) that record vegetation responses to past climate changes. These observed vegetation data can be combined with mechanistic vegetation model simulations to develop process-based evaluations of paleoclimate model simulations. The use of mechanistic vegetation model simulations allows us to identify the particular spatial and temporal features of individual paleoclimate simulations that may be producing agreement or disagreement between the observed and simulated vegetation data. We used this approach to evaluate a set of eight PMIP3 (Paleoclimate Modelling Intercomparison Project phase 3) paleoclimate simulations for 6 ka and 21 ka from the CMIP5 (Coupled Model Intercomparison Project phase 5) database. Climate data were regridded onto a 10-km grid of North America using the PMIP3 vegetation simulation protocol. The regridded climate data were used as input to BIOME4, an equilibrium vegetation model, to simulate 6 ka and 21 ka biomes across the study area. The simulated biome data were compared with observed paleovegetation data from the BIOME 6000 (version 4.2) dataset. In general, agreement between simulated and observed biomes was greater for forest biomes than for non-forest biomes. We evaluated specific instances of disagreement between the simulated and observed biomes to determine whether the biome disagreement was produced by the climate model simulation (e.g., temperature bias), the vegetation model simulation (e.g., inability to simulate important disturbance regimes), the observed paleovegetation data (e.g., limits in the biomization method), or a combination of these factors. The results are summarized and we describe some of the strengths and limitations of this data-model comparison approach for evaluating paleoclimate simulations.

  9. Atmospheric pressure plasma jet for bacterial decontamination and property improvement of fruit and vegetable processing wastewater

    NASA Astrophysics Data System (ADS)

    Mohamed, Abdel-Aleam H.; Shariff, Samir M. Al; Ouf, Salama A.; Benghanem, Mohamed

    2016-05-01

    An atmospheric pressure plasma jet was tested for decontaminating and improving the characteristics of wastewater derived from blackberry, date palm, tomato and beetroot processing industries. The jet was generated by blowing argon gas through a cylindrical alumina tube while a high voltage was applied between two electrodes surrounding the tube. Oxygen gas was mixed with argon at the rate of 0.2% and the argon mass flow was fixed at 4.5 slm. Images show that the generated plasma jet penetrated the treated wastewater samples. Plasma emission spectra show the presence of O and OH radicals as well as excited molecular nitrogen and argon. Complete decontamination of wastewater derived from date palm and tomato processing was achieved after 120 and 150 s exposure to the plasma jet, respectively. The bacterial count of wastewater from blackberry and beetroot was reduced by 0.41 and 2.24 log10 colony-forming units (CFU) per ml, respectively, after 180 s. Escherichia coli was the most susceptible bacterial species to the cold plasma while Shigella boydii had the minimum susceptibility, recording 1.30 and 3.34 log10 CFU ml‑1, respectively, as compared to the 7.00 log10 initial count. The chemical oxygen demands of wastewater were improved by 57.5–93.3% after 180 s exposure to the plasma jet being tested. The endotoxins in the wastewater were reduced by up to 90.22%. The variation in plasma effectiveness is probably related to the antioxidant concentration of the different investigated wastewaters.

  10. Simulating boreal forest carbon dynamics after stand-replacing fire disturbance: insights from a global process-based vegetation model

    NASA Astrophysics Data System (ADS)

    Yue, C.; Ciais, P.; Luyssaert, S.; Cadule, P.; Harden, J.; Randerson, J.; Bellassen, V.; Wang, T.; Piao, S. L.; Poulter, B.; Viovy, N.

    2013-04-01

    Stand-replacing fires are the dominant fire type in North American boreal forest and leave a historical legacy of a mosaic landscape of different aged forest cohorts. To accurately quantify the role of fire in historical and current regional forest carbon balance using models, one needs to explicitly simulate the new forest cohort that is established after fire. The present study adapted the global process-based vegetation model ORCHIDEE to simulate boreal forest fire CO2 emissions and follow-up recovery after a stand-replacing fire, with representation of postfire new cohort establishment, forest stand structure and the following self-thinning process. Simulation results are evaluated against three clusters of postfire forest chronosequence observations in Canada and Alaska. Evaluation variables for simulated postfire carbon dynamics include: fire carbon emissions, CO2 fluxes (gross primary production, total ecosystem respiration and net ecosystem exchange), leaf area index (LAI), and biometric measurements (aboveground biomass carbon, forest floor carbon, woody debris carbon, stand individual density, stand basal area, and mean diameter at breast height). The model simulation results, when forced by local climate and the atmospheric CO2 history on each chronosequence site, generally match the observed CO2 fluxes and carbon stock data well, with model-measurement mean square root of deviation comparable with measurement accuracy (for CO2 flux ~100 g C m-2 yr-1, for biomass carbon ~1000 g C m-2 and for soil carbon ~2000 g C m-2). We find that current postfire forest carbon sink on evaluation sites observed by chronosequence methods is mainly driven by historical atmospheric CO2 increase when forests recover from fire disturbance. Historical climate generally exerts a negative effect, probably due to increasing water stress caused by significant temperature increase without sufficient increase in precipitation. Our simulation results demonstrate that a global

  11. Effect of plant dynamic processes on African vegetation responses to climate change: Analysis using the spatially explicit individual-based dynamic global vegetation model (SEIB-DGVM)

    NASA Astrophysics Data System (ADS)

    Sato, Hisashi; Ise, Takeshi

    2012-09-01

    We applied a dynamic global vegetation model (DGVM) to the African continent. After calibration, the model reproduced geographical distributions of the continent's biomes, annual gross primary productivity (GPP), and biomass under current climatic conditions. The model is driven by the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emission Scenarios (SRES) A1B scenario of rising CO2, and by climate changes during the twenty-first century resulting from the change in CO2concentrations, simulated by a coupled Model for Interdisciplinary Research on Climate (MIROC) ocean atmosphere model. Simulations under this condition revealed time lags between environmental change and biome change, with the extent of these lags depending largely on the type of biome change. A switch in forest type was accompanied by the longest delay in biome change among all changes classified, indicating that resident trees largely prevent the establishment of nonresident tree types adapted to the new environment, and that tree growth requires additional years after successful establishment. In addition, assumptions for tree dispersal, which determine whether nonresident tree types can be established, modified the patterns of biome change under the twenty-first-century environment: under the assumption that nonresident tree types cannot be established even if environmental conditions change, the extent of the forest type switch and the development of forest and savanna were suppressed, while forest dieback was enhanced. These changes accompanied a slowing of the increasing trend in net primary productivity (NPP), biomass, and soil carbon during the twenty-first century and in subsequent years. These results quantitatively demonstrate that both patch dynamics and invasive tree recruitment significantly modify the transient change in vegetation distribution and function under a changing environment on the African continent.

  12. Effect of plant dynamic processes on African vegetation responses to climate change: Analysis using the spatially explicit individual-based dynamic global vegetation model (SEIB-DGVM)

    NASA Astrophysics Data System (ADS)

    SATO, H.; Ise, T.

    2012-12-01

    We applied a dynamic global vegetation model (DGVM) to the African continent. After calibration, the model reproduced geographical distributions of the continent's biomes, annual gross primary productivity (GPP), and biomass under current climatic conditions. The model is driven by the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emission Scenarios (SRES) A1B scenario of rising CO2, and by climate changes during the 21st century resulting from the change in CO2 concentrations, simulated by a coupled Model for Interdisciplinary Research on Climate (MIROC) ocean atmosphere model. Simulations under this condition revealed time lags between environmental change and biome change, with the extent of these lags depending largely on the type of biome change. A switch in forest type was accompanied by the longest delay in biome change among all changes classified, indicating that resident trees largely prevent the establishment of non-resident tree types adapted to the new environment, and that tree growth requires additional years after successful establishment. In addition, assumptions for tree dispersal, which determine whether non-resident tree types can be established, modified the patterns of biome change under the 21st century environment: under the assumption that non-resident tree types cannot be established even if environmental conditions change, the extent of the forest type switch and the development of forest and savanna were suppressed, while forest dieback was enhanced. These changes accompanied a slowing of the increasing trend in net primary productivity (NPP), biomass, and soil carbon during the 21st century and in subsequent years. These results quantitatively demonstrate that both patch dynamics and invasive tree recruitment significantly modify the transient change in vegetation distribution and function under a changing environment on the African continent. Sato H & Ise T (2012) Journal of Geophysical Research - Biogeosciences

  13. Effect of processing by hydrostatic high pressure of two ready to heat vegetable meals and stability after refrigerated storage.

    PubMed

    Masegosa, Rosa; Delgado-Adámez, Jonathan; Contador, Rebeca; Sánchez-Íñiguez, Francisco; Ramírez, Rosario

    2014-12-01

    The effect of high pressure processing (HPP) (400 and 600 MPa for 1 and 5 min) and the stability during storage were studied in two ready to heat vegetable meals: meal A, mainly composed by pumpkin and broccoli, and meal B, mainly composed by eggplant, zucchini, chard and spinach. The treatment at 600 MPa/5 min was the most effective to reduce the initial microbial loads of the meals and maintained better the microbial safety during storage. HPP had no effect on the physico-chemical and sensory properties. HPP at 600 MPa increased the antioxidant activity of the meal A. In contrast HPP reduced the antioxidant activity of the meal B, although in general high levels of antioxidants were maintained after processing and during storage. In conclusion, treatments at 600 MPa for 5 min were the most suitable to increase the shelf-life of the meals without affecting their physico-chemical, antioxidant and sensory properties. PMID:23908392

  14. Tannin fingerprinting in vegetable tanned leather by solid state NMR spectroscopy and comparison with leathers tanned by other processes.

    PubMed

    Romer, Frederik H; Underwood, Andrew P; Senekal, Nadine D; Bonnet, Susan L; Duer, Melinda J; Reid, David G; van der Westhuizen, Jan H

    2011-01-01

    Solid state ¹³C-NMR spectra of pure tannin powders from four different sources--mimosa, quebracho, chestnut and tara--are readily distinguishable from each other, both in pure commercial powder form, and in leather which they have been used to tan. Groups of signals indicative of the source, and type (condensed vs. hydrolyzable) of tannin used in the manufacture are well resolved in the spectra of the finished leathers. These fingerprints are compared with those arising from leathers tanned with other common tanning agents. Paramagnetic chromium (III) tanning causes widespread but selective disappearance of signals from the spectrum of leather collagen, including resonances from acidic aspartyl and glutamyl residues, likely bound to Cr (III) structures. Aluminium (III) and glutaraldehyde tanning both cause considerable leather collagen signal sharpening suggesting some increase in molecular structural ordering. The ²⁷Al-NMR signal from the former material is consistent with an octahedral coordination by oxygen ligands. Solid state NMR thus provides easily recognisable reagent specific spectral fingerprints of the products of vegetable and some other common tanning processes. Because spectra are related to molecular properties, NMR is potentially a powerful tool in leather process enhancement and quality or provenance assurance. PMID:21278677

  15. Using UAVs and digital image processing to quantify areas of soil and vegetation

    NASA Astrophysics Data System (ADS)

    Chaves, A. A.; La Scalea, R. A.; Colturato, A. B.; Kawabata, C. L. O.; Furtado, E. L.; Castelo Branco, K. R. L. J.

    2015-09-01

    Unmanned aerial vehicles (UAVs) are becoming a very popular tool for remote sensing and crop monitoring. They are more easily deployed, cheaper and can obtain images with higher spatial-resolution than satellites. Some small, commercial UAVs can obtain images with spatial-resolution as low as 1.5cm per pixel. This opens up the range of possible remote sensing and monitoring applications. Moreover, they can cover large areas in very little time, such as 50 ha in about 20min, which makes UAVs the ideal tool for monitoring large farms and plantations. On the other hand, it is important to know precisely the area covered by farms in order to avoid invasion of other properties or preserved areas, and also to detect flaws in the plantation area. However, it is difficult to measure planted areas in some cases, such as Eucalyptus crops. Therefore, this paper aims to evaluate the use of UAV imagery for precise area measurement in Eucalyptus crops. We developed an image-processing algorithm to segment regions of soil, low biomass and high biomass and tested it on a Eucalyptus plantation in the city of Lenis Paulista -SP, Brazil. Results show that the area quantification is very accurate especially for bare soil regions and this method can be used to estimate areas in other scenarios.

  16. An integrated modelling framework of catchment-scale ecohydrological processes: 2. The role of water subsidy by overland flow on vegetation dynamics in a semi-arid catchment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In water-limited regions, surface water and carbon fluxes are strongly controlled by soil water availability, which may be highly variable at very small spatial scales (e.g. metres) because of variations in terrain, soils, and vegetation conditions and to processes of water redistribution along hill...

  17. New Bio-Ceramization Processes Applied to Vegetable Hierarchical Structures for Bone Regeneration: An Experimental Model in Sheep

    PubMed Central

    Filardo, Giuseppe; Tampieri, Anna; Cabezas-Rodríguez, Rafael; Di Martino, Alessandro; Fini, Milena; Giavaresi, Gianluca; Lelli, Marco; Martínez-Fernández, Julian; Martini, Lucia; Ramírez-Rico, Joaquin; Salamanna, Francesca; Sandri, Monica; Sprio, Simone; Marcacci, Maurilio

    2014-01-01

    Bone loss is still a major problem in orthopedics. The purpose of this experimental study is to evaluate the safety and regenerative potential of a new scaffold based on a bio-ceramization process for bone regeneration in long diaphyseal defects in a sheep model. The scaffold was obtained by transformation of wood pieces into porous biomorphic silicon carbide (BioSiC®). The process enabled the maintenance of the original wood microstructure, thus exhibiting hierarchically organized porosity and high mechanical strength. To improve cell adhesion and osseointegration, the external surface of the hollow cylinder was made more bioactive by electrodeposition of a uniform layer of collagen fibers that were mineralized with biomimetic hydroxyapatite, whereas the internal part was filled with a bio-hybrid HA/collagen composite. The final scaffold was then implanted in the metatarsus of 15 crossbred (Merinos-Sarda) adult sheep, divided into 3 groups: scaffold alone, scaffold with platelet-rich plasma (PRP) augmentation, and scaffold with bone marrow stromal cells (BMSCs) added during implantation. Radiological analysis was performed at 4, 8, 12 weeks, and 4 months, when animals were sacrificed for the final radiological, histological, and histomorphometric evaluation. In all tested treatments, these analyses highlighted the presence of newly formed bone at the bone scaffolds' interface. Although a lack of substantial effect of PRP was demonstrated, the scaffold+BMSC augmentation showed the highest value of bone-to-implant contact and new bone growth inside the scaffold. The findings of this study suggest the potential of bio-ceramization processes applied to vegetable hierarchical structures for the production of wood-derived bone scaffolds, and document a suitable augmentation procedure in enhancing bone regeneration, particularly when combined with BMSCs. PMID:24099033

  18. Hillslope soils and vegetation

    NASA Astrophysics Data System (ADS)

    Amundson, Ronald; Heimsath, Arjun; Owen, Justine; Yoo, Kyungsoo; Dietrich, William E.

    2015-04-01

    Assessing how vegetation controls hillslope soil processes is a challenging problem, as few abiotic landscapes exist as observational controls. Here we identify five avenues to examine how actively eroding hillslope soils and processes would differ without vegetation, and we explore some potential feedbacks that may result in landscape resilience on vegetated hillslopes. The various approaches suggest that a plant-free world would be characterized by largely soil-free hillslopes, that plants may control the maximum thickness of soils on slopes, that vegetated landforms erode at rates about one order of magnitude faster than plant-free outcrops in comparable settings, and that vegetated hillslope soils generally maintain long residence times such that both N and P sufficiency for ecosystems is the norm. We conclude that quantitatively parameterizing biota within process-based hillslope models needs to be a priority in order to project how human activity may further impact the soil mantle.

  19. Responses of eastern Chinese coastal salt marshes to sea-level rise combined with vegetative and sedimentary processes.

    PubMed

    Ge, Zhen-Ming; Wang, Heng; Cao, Hao-Bin; Zhao, Bin; Zhou, Xiao; Peltola, Heli; Cui, Li-Fang; Li, Xiu-Zhen; Zhang, Li-Quan

    2016-01-01

    The impacts of sea-level rise (SLR) on coastal ecosystems have attracted worldwide attention in relation to global change. In this study, the salt marsh model for the Yangtze Estuary (SMM-YE, developed in China) and the Sea Level Affecting Marshes Model (SLAMM, developed in the U.S.) were used to simulate the effects of SLR on the coastal salt marshes in eastern China. The changes in the dominant species in the plant community were also considered. Predictions based on the SLAMM indicated a trend of habitat degradation up to 2100; total salt marsh habitat area continued to decline (4-16%) based on the low-level scenario, with greater losses (6-25%) predicted under the high-level scenario. The SMM-YE showed that the salt marshes could be resilient to threats of SLR through the processes of accretion of mudflats, vegetation expansion and sediment trapping by plants. This model predicted that salt marsh areas increased (3-6%) under the low-level scenario. The decrease in the total habitat area with the SMM-YE under the high-level scenario was much lower than the SLAMM prediction. Nevertheless, SLR might negatively affect the salt marsh species that are not adapted to prolonged inundation. An adaptive strategy for responding to changes in sediment resources is necessary in the Yangtze Estuary. PMID:27334452

  20. Responses of eastern Chinese coastal salt marshes to sea-level rise combined with vegetative and sedimentary processes

    PubMed Central

    Ge, Zhen-Ming; Wang, Heng; Cao, Hao-Bin; Zhao, Bin; Zhou, Xiao; Peltola, Heli; Cui, Li-Fang; Li, Xiu-Zhen; Zhang, Li-Quan

    2016-01-01

    The impacts of sea-level rise (SLR) on coastal ecosystems have attracted worldwide attention in relation to global change. In this study, the salt marsh model for the Yangtze Estuary (SMM-YE, developed in China) and the Sea Level Affecting Marshes Model (SLAMM, developed in the U.S.) were used to simulate the effects of SLR on the coastal salt marshes in eastern China. The changes in the dominant species in the plant community were also considered. Predictions based on the SLAMM indicated a trend of habitat degradation up to 2100; total salt marsh habitat area continued to decline (4–16%) based on the low-level scenario, with greater losses (6–25%) predicted under the high-level scenario. The SMM-YE showed that the salt marshes could be resilient to threats of SLR through the processes of accretion of mudflats, vegetation expansion and sediment trapping by plants. This model predicted that salt marsh areas increased (3–6%) under the low-level scenario. The decrease in the total habitat area with the SMM-YE under the high-level scenario was much lower than the SLAMM prediction. Nevertheless, SLR might negatively affect the salt marsh species that are not adapted to prolonged inundation. An adaptive strategy for responding to changes in sediment resources is necessary in the Yangtze Estuary. PMID:27334452

  1. Responses of eastern Chinese coastal salt marshes to sea-level rise combined with vegetative and sedimentary processes

    NASA Astrophysics Data System (ADS)

    Ge, Zhen-Ming; Wang, Heng; Cao, Hao-Bin; Zhao, Bin; Zhou, Xiao; Peltola, Heli; Cui, Li-Fang; Li, Xiu-Zhen; Zhang, Li-Quan

    2016-06-01

    The impacts of sea-level rise (SLR) on coastal ecosystems have attracted worldwide attention in relation to global change. In this study, the salt marsh model for the Yangtze Estuary (SMM-YE, developed in China) and the Sea Level Affecting Marshes Model (SLAMM, developed in the U.S.) were used to simulate the effects of SLR on the coastal salt marshes in eastern China. The changes in the dominant species in the plant community were also considered. Predictions based on the SLAMM indicated a trend of habitat degradation up to 2100; total salt marsh habitat area continued to decline (4–16%) based on the low-level scenario, with greater losses (6–25%) predicted under the high-level scenario. The SMM-YE showed that the salt marshes could be resilient to threats of SLR through the processes of accretion of mudflats, vegetation expansion and sediment trapping by plants. This model predicted that salt marsh areas increased (3–6%) under the low-level scenario. The decrease in the total habitat area with the SMM-YE under the high-level scenario was much lower than the SLAMM prediction. Nevertheless, SLR might negatively affect the salt marsh species that are not adapted to prolonged inundation. An adaptive strategy for responding to changes in sediment resources is necessary in the Yangtze Estuary.

  2. Towards an understanding of coupled physical and biological processes in the cultivated Sahel - 2. Vegetation and carbon dynamics

    NASA Astrophysics Data System (ADS)

    Boulain, N.; Cappelaere, B.; Ramier, D.; Issoufou, H. B. A.; Halilou, O.; Seghieri, J.; Guillemin, F.; Oï, M.; Gignoux, J.; Timouk, F.

    2009-08-01

    SummaryThis paper analyses the dynamics of vegetation and carbon during the West African monsoon season, for millet crop and fallow vegetation covers in the cultivated area of the Sahel. Comparing these two dominant land cover types informs on the impact of cultivation on productivity and carbon fluxes. Biomass, leaf area index (LAI) and carbon fluxes were monitored over a 2-year period for these two vegetation systems in the Wankama catchment of the AMMA (African monsoon multidisciplinary analyses) experimental super-site in West Niger. Carbon fluxes and water use efficiency observed at the field scale are confronted with ecophysiological measurements (photosynthetic response to light, and relation of water use efficiency to air humidity) made at the leaf scale for the dominant plant species in the two vegetation systems. The two rainy seasons monitored were dissimilar with respect to rain patterns, reflecting some of the interannual variability. Distinct responses in vegetation development and in carbon dynamics were observed between the two vegetation systems. Vegetation development in the fallow was found to depend more on rainfall distribution along the season than on its starting date. A quite opposite behaviour was observed for the crop vegetation: the date of first rain appears as a principal factor of millet growth. Carbon flux exchanges were well correlated to vegetation development. High responses of photosynthesis to light were observed for the dominant herbaceous and shrub species of the fallow at the leaf and field scales. Millet showed high response at the leaf scale, but a much lesser response at the field scale. This pattern, also observed for water use efficiency, is to be related to the low density of the millet cover. A simple LAI-based model for scaling up the photosynthetic response from leaf to field scale was found quite successful for the fallow, but was less conclusive for the crop, due to spatial variability of LAI. Time/space variations

  3. Parent material, vegetation or slope position - which soil-forming factor controls the intensity of podzolization process in the soils of the Sudety Mountains montane zone?

    NASA Astrophysics Data System (ADS)

    Musielok, Łukasz

    2016-04-01

    Climatic conditions, parent material and vegetation type are considered to be the main soil-forming factors controlling podzolization process advancement. Moreover, in hilly and mountainous areas properties of soils that are undergoing podzolization process are influenced significantly by its location on a slope, due to lateral translocation of soil solutions. The Sudety Mts. are a medium-high mountain range characterized by geological mosaic with many different sedimentary, igneous and metamorphic rocks, mostly poor in alkali elements. Most of the Sudety Mts. area lies in a lower montane zone, where the dominant natural vegetation were temperate mixed and deciduous forests. However, since 18th century natural vegetation was significantly transformed by widespread introduction of spruce monocultures. These distinguishing features of the Sudety Mts. natural environment are considered to be responsible for prevalence of podzolized soil in this area, however the intensity of podzolization process is very differentiated. The aim of presented research was to determine the influence of varying parent material, different vegetation types and different slope positions the on the soil properties variability, and thus, to answer the question which of the analyzed soil-forming factors is controlling the podzolization process advancement in the Sudety Mountains montane zone? Data from A, E, Bs and C horizons of 16 soil profiles developed from different parent materials (granite, sandstone, andesites and mica schists), located under various types of vegetation (spruce and beech forests) and in different slope positions (upper, middle and lower parts of the slopes) were taken into the analysis. All analyzed soil profiles were located in lower montane zone between 550 and 950 m a. s. l. to avoid the influence of varying climatic conditions. One-way ANOVA and Principal Components Analysis (PCA) were used to analyze differentiation of soil texture, pH, organic carbon and nitrogen

  4. ChSte7 Is Required for Vegetative Growth and Various Plant Infection Processes in Colletotrichum higginsianum

    PubMed Central

    Chen, Meijuan; Yan, Yaqin; Gu, Qiongnan; Huang, Junbin

    2016-01-01

    Colletotrichum higginsianum is an important hemibiotrophic phytopathogen that causes crucifer anthracnose in various regions of the world. In many plant-pathogenic fungi, the Ste11-Ste7-Fus3/Kss1 kinase pathway is essential to pathogenicity and various plant infection processes. To date, the role of ChSte7 in C. higginsianum encoding a MEK orthologue of Ste7 in Saccharomyces cerevisiae has not been elucidated. In this report, we investigated the function of ChSte7 in the pathogen. The ChSte7 is predicted to encode a 522-amino-acid protein with a S_TKc conserved domain that shares 44% identity with Ste7 in S. cerevisiae. ChSte7 disruption mutants showed white colonies with irregularly shaped edges and extremely decreased growth rates and biomass productions. The ChSte7 disruption mutants did not form appressoria and showed defects in pathogenicity on leaves of Arabidopsis thaliana. When inoculated onto wounded leaf tissues, the ChSte7 disruption mutants grew only on the surface of host tissues but failed to cause lesions beyond the wound site. In contrast, both the wild-type and complementation strains showed normal morphology, produced appressoria, and caused necrosis on leaves of Arabidopsis. Analysis with qRT-PCR suggested that ChSte7 was highly expressed during the late stages of infection. Taken together, our results demonstrate that ChSte7 is involved in regulation of vegetative growth, appressorial formation of C. higginsianum, and postinvasive growth in host tissues. PMID:27563675

  5. ChSte7 Is Required for Vegetative Growth and Various Plant Infection Processes in Colletotrichum higginsianum.

    PubMed

    Yuan, Qinfeng; Chen, Meijuan; Yan, Yaqin; Gu, Qiongnan; Huang, Junbin; Zheng, Lu

    2016-01-01

    Colletotrichum higginsianum is an important hemibiotrophic phytopathogen that causes crucifer anthracnose in various regions of the world. In many plant-pathogenic fungi, the Ste11-Ste7-Fus3/Kss1 kinase pathway is essential to pathogenicity and various plant infection processes. To date, the role of ChSte7 in C. higginsianum encoding a MEK orthologue of Ste7 in Saccharomyces cerevisiae has not been elucidated. In this report, we investigated the function of ChSte7 in the pathogen. The ChSte7 is predicted to encode a 522-amino-acid protein with a S_TKc conserved domain that shares 44% identity with Ste7 in S. cerevisiae. ChSte7 disruption mutants showed white colonies with irregularly shaped edges and extremely decreased growth rates and biomass productions. The ChSte7 disruption mutants did not form appressoria and showed defects in pathogenicity on leaves of Arabidopsis thaliana. When inoculated onto wounded leaf tissues, the ChSte7 disruption mutants grew only on the surface of host tissues but failed to cause lesions beyond the wound site. In contrast, both the wild-type and complementation strains showed normal morphology, produced appressoria, and caused necrosis on leaves of Arabidopsis. Analysis with qRT-PCR suggested that ChSte7 was highly expressed during the late stages of infection. Taken together, our results demonstrate that ChSte7 is involved in regulation of vegetative growth, appressorial formation of C. higginsianum, and postinvasive growth in host tissues. PMID:27563675

  6. An Evaluation of Processes Critical to Predicting the Carbon Sink of Natural Tropical Forests in a Demographic Vegetation Model

    NASA Astrophysics Data System (ADS)

    Knox, R. G.; Holm, J. A.; Chambers, J. Q.; Longo, M.; Moorcroft, P. R.; Higuchi, N.; Riley, W. J.; Manzi, A. O.; Koven, C. D.

    2014-12-01

    The direct effects of rising atmospheric CO2 concentrations on tropical forests have been the focus of a large body of research including manipulative experiments, observational studies and model estimation. The work presented here seeks to evaluate the processes involved in modelling forest dynamics under changes in atmospheric CO2, and ascertain the strengths and deficiencies of these representations. To do this, the Ecosystem Demography Model 2 (ED2) and the Community Land Model (CLM 4.5-BGC) are used to simulate the vegetation dynamics of an old-growth Central Amazonian forest through the next century, and are compared with flux and inventory data. Using default calibrations (regional specificity), both models were found to overestimate mortality rate and biomass increment (by 1.4 and 0.8 Mg ha-1 yr-1 in ED2 and CLM respectively). This comparison has lead to a closer examination of mortality, the allocation of assimilated carbon and the phasing of plant competition. An analysis of model output and literature review corroborate that tree mortality in old growth tropical forests is complex and is driven by a variety of mechanisms. We find that mortality parameterizations used in earth system models may benefit from simplicity until a more comprehensive mechanistic understanding of mortality and its drivers becomes available. An analysis of field data also showed that a significant fraction of mature trees in the upper canopy were exhibiting no increment in growth. It is not immediately clear if these trees are exhibiting decreased net primary production, or alternatively, how these trees have shifted their resource usage strategy. Demographic ecosystem models such as ED2 provide a means to represent and test these alternative hypotheses as they emerge.

  7. Quantitative assessment of the Salmonella distribution on fresh-cut leafy vegetables due to cross-contamination occurred in an industrial process simulated at laboratory scale.

    PubMed

    Pérez-Rodríguez, Fernando; Saiz-Abajo, M José; Garcia-Gimeno, R M; Moreno, Ana; González, David; Vitas, Ana Isabel

    2014-08-01

    Fecal pathogen distributions in fresh-cut leafy vegetables are essential to develop suitable sampling plans so as to detect pathogen contaminations. In this study, a typical fresh-cut lettuce process was reproduced at pilot scale with different initial inoculum levels of Salmonella on lettuce (6-7, 4 and 1 log CFU/g). The pathogen was determined in all processed lettuce samples (n ≥ 50) and obtained count data were used to fit different probability distributions. The study showed that Salmonella is homogenously distributed on fresh-cut leafy vegetables as a result of processing (mainly washing) at all contamination levels. Negative binomial and Poisson-lognormal distributions were suitable to describe pathogen distribution at the high and medium levels. coefficient of variation modified (CV) indicated no overdispersion (i.e. clustering). Nevertheless, further research will be needed to assess the effect of using disinfectants in washing water on the final distribution pattern of pathogens in processed fresh-cut leafy vegetables. PMID:24943007

  8. The fire effect on Cerrado: Analysis of the erosive process associated with native vegetation by the use of experimental plots

    NASA Astrophysics Data System (ADS)

    Costa, Yasmmin; Rodrigues, Sílvio

    2015-04-01

    In Brazil vast areas of vegetation are devastated each year by the use of fire that recorded more than 200,000 hotspots annually. In this context, the state of Minas Gerais appears first in the number of fires and burned areas due to its long stretch of reforested area in an environment where a prolonged dry season contributes to the occurrence and spread of fire in the Cerrado vegetation. This research consists of a comparative study through the controlled application of fire under different conditions of natural vegetation of the focusing on the change in rates of runoff, sediment production and vegetation density in order to evaluate the influence of burning related to soil erosion. The area of study is located in Uberlândia at an altitude of 850 meters above sea level and in the respective geographic coordinates 18°56'56"S and 48°12'21"W that composes the watershed of Glória stream. The climate is characterized by dry winters and rainy summer. On this area five experimental plots was established from the specific characteristic of its vegetation cover, slope and drainage, thus differentiated: well drained soil with the presence of a dense grass (plot A), well drained soil with the presence of shrub and grasses (plot B), poorly drained with a non-dense grass (plot C), well drained soil with grass (plot D), and well drained with grasses and tree cover(plot E). The plots have 1m2 that is connected with a trough collector that concentrate the water flow generated by runoff with a 30 liter gallon that was weekly measured. The data relating to runoff and sediment yield were obtained from the collection of water derived from water stored in gallons, in which first was homogenized, measured quantity and collected 1 liter of water to be filtrated in the laboratory. The analysis method of vegetation density was performed based on the methodology proposed by Pinese Junior, Cruz and Rodrigues (2008), using the software ENVI 4.3 to interpret and quantify the image

  9. Dietary fruit, vegetable, fat, and red and processed meat intakes and Barrett’s esophagus risk: a systematic review and meta-analysis

    PubMed Central

    Zhao, Zhanwei; Pu, Zhongshu; Yin, Zifang; Yu, Pengfei; Hao, Yiming; Wang, Qian; Guo, Min; Zhao, Qingchuan

    2016-01-01

    The relationships between dietary fruit, vegetable, fat, and red and processed meat intakes and Barrett’s esophagus (BE) risk remain inconclusive. We conducted a systematic review and meta-analysis to summarize the available evidence on these issues. PubMed, EMBASE and the Cochrane Library were searched for studies published from inception through October 2015. A total of eight studies were included in this analysis. Fruit intake was not associated with BE risk (OR = 0.65, 95% CI = 0.37–1.13), but vegetable intake was strongly associated with BE risk (OR = 0.45, 95% CI = 0.29–0.71). Saturated fat, red meat and processed meat intakes were not associated with BE risk with OR = 1.25 (95% CI = 0.82–1.91), OR = 0.85 (95% CI = 0.61–1.17) and OR = 1.03 (95% CI = 0.73–1.46), respectively. Dietary vegetable not fruits intake may be associated with decreased BE risk. Fat and red and processed meat intakes may not contribute to an increased BE risk. Well-designed, large prospective studies with better established dose-response relationships are needed to further validate these issues. PMID:27256629

  10. Dietary fruit, vegetable, fat, and red and processed meat intakes and Barrett's esophagus risk: a systematic review and meta-analysis.

    PubMed

    Zhao, Zhanwei; Pu, Zhongshu; Yin, Zifang; Yu, Pengfei; Hao, Yiming; Wang, Qian; Guo, Min; Zhao, Qingchuan

    2016-01-01

    The relationships between dietary fruit, vegetable, fat, and red and processed meat intakes and Barrett's esophagus (BE) risk remain inconclusive. We conducted a systematic review and meta-analysis to summarize the available evidence on these issues. PubMed, EMBASE and the Cochrane Library were searched for studies published from inception through October 2015. A total of eight studies were included in this analysis. Fruit intake was not associated with BE risk (OR = 0.65, 95% CI = 0.37-1.13), but vegetable intake was strongly associated with BE risk (OR = 0.45, 95% CI = 0.29-0.71). Saturated fat, red meat and processed meat intakes were not associated with BE risk with OR = 1.25 (95% CI = 0.82-1.91), OR = 0.85 (95% CI = 0.61-1.17) and OR = 1.03 (95% CI = 0.73-1.46), respectively. Dietary vegetable not fruits intake may be associated with decreased BE risk. Fat and red and processed meat intakes may not contribute to an increased BE risk. Well-designed, large prospective studies with better established dose-response relationships are needed to further validate these issues. PMID:27256629

  11. Headspace components that discriminate between thermal and high pressure high temperature treated green vegetables: identification and linkage to possible process-induced chemical changes.

    PubMed

    Kebede, Biniam T; Grauwet, Tara; Tabilo-Munizaga, Gipsy; Palmers, Stijn; Vervoort, Liesbeth; Hendrickx, Marc; Van Loey, Ann

    2013-12-01

    For the first time in literature, this study compares the process-induced chemical reactions in three industrially relevant green vegetables: broccoli, green pepper and spinach treated with thermal and high pressure high temperature (HPHT) processing. Aiming for a fair comparison, the processing conditions were selected based on the principle of equivalence. A comprehensive integration of MS-based metabolic fingerprinting techniques, advanced data preprocessing and statistical data analysis has been implemented as untargeted/unbiased multiresponse screening tool to uncover changes in the volatile fraction. For all vegetables, thermal processing, compared to HPHT, seems to enhance Maillard and Strecker degradation reaction, triggering the formation of furanic compounds and Strecker aldehydes. In most cases, high pressure seems to accelerate (an)aerobic thermal degradation of unsaturated fatty acids leading to the formation of aliphatic aldehydes and ketones. In addition, both thermal and HPHT processing accelerated the formation of sulfur-containing compounds. This work demonstrated that the approach is effective in identifying and comparing different process-induced chemical changes, adding depth to our perspective in terms of studying a highly complex chemical changes occurring during food processing. PMID:23870866

  12. Where does the carbon go? A model–data intercomparison of vegetation carbon allocation and turnover processes at two temperate forest free-air CO2 enrichment sites

    PubMed Central

    De Kauwe, Martin G; Medlyn, Belinda E; Zaehle, Sönke; Walker, Anthony P; Dietze, Michael C; Wang, Ying-Ping; Luo, Yiqi; Jain, Atul K; El-Masri, Bassil; Hickler, Thomas; Wårlind, David; Weng, Ensheng; Parton, William J; Thornton, Peter E; Wang, Shusen; Prentice, I Colin; Asao, Shinichi; Smith, Benjamin; McCarthy, Heather R; Iversen, Colleen M; Hanson, Paul J; Warren, Jeffrey M; Oren, Ram; Norby, Richard J

    2014-01-01

    Elevated atmospheric CO2 concentration (eCO2) has the potential to increase vegetation carbon storage if increased net primary production causes increased long-lived biomass. Model predictions of eCO2 effects on vegetation carbon storage depend on how allocation and turnover processes are represented. We used data from two temperate forest free-air CO2 enrichment (FACE) experiments to evaluate representations of allocation and turnover in 11 ecosystem models. Observed eCO2 effects on allocation were dynamic. Allocation schemes based on functional relationships among biomass fractions that vary with resource availability were best able to capture the general features of the observations. Allocation schemes based on constant fractions or resource limitations performed less well, with some models having unintended outcomes. Few models represent turnover processes mechanistically and there was wide variation in predictions of tissue lifespan. Consequently, models did not perform well at predicting eCO2 effects on vegetation carbon storage. Our recommendations to reduce uncertainty include: use of allocation schemes constrained by biomass fractions; careful testing of allocation schemes; and synthesis of allocation and turnover data in terms of model parameters. Data from intensively studied ecosystem manipulation experiments are invaluable for constraining models and we recommend that such experiments should attempt to fully quantify carbon, water and nutrient budgets. PMID:24844873

  13. Where does the carbon go? A model-data intercomparison of vegetation carbon allocation and turnover processes at two temperate forest free-air CO2 enrichment sites.

    PubMed

    De Kauwe, Martin G; Medlyn, Belinda E; Zaehle, Sönke; Walker, Anthony P; Dietze, Michael C; Wang, Ying-Ping; Luo, Yiqi; Jain, Atul K; El-Masri, Bassil; Hickler, Thomas; Wårlind, David; Weng, Ensheng; Parton, William J; Thornton, Peter E; Wang, Shusen; Prentice, I Colin; Asao, Shinichi; Smith, Benjamin; McCarthy, Heather R; Iversen, Colleen M; Hanson, Paul J; Warren, Jeffrey M; Oren, Ram; Norby, Richard J

    2014-08-01

    Elevated atmospheric CO2 concentration (eCO2) has the potential to increase vegetation carbon storage if increased net primary production causes increased long-lived biomass. Model predictions of eCO2 effects on vegetation carbon storage depend on how allocation and turnover processes are represented. We used data from two temperate forest free-air CO2 enrichment (FACE) experiments to evaluate representations of allocation and turnover in 11 ecosystem models. Observed eCO2 effects on allocation were dynamic. Allocation schemes based on functional relationships among biomass fractions that vary with resource availability were best able to capture the general features of the observations. Allocation schemes based on constant fractions or resource limitations performed less well, with some models having unintended outcomes. Few models represent turnover processes mechanistically and there was wide variation in predictions of tissue lifespan. Consequently, models did not perform well at predicting eCO2 effects on vegetation carbon storage. Our recommendations to reduce uncertainty include: use of allocation schemes constrained by biomass fractions; careful testing of allocation schemes; and synthesis of allocation and turnover data in terms of model parameters. Data from intensively studied ecosystem manipulation experiments are invaluable for constraining models and we recommend that such experiments should attempt to fully quantify carbon, water and nutrient budgets. PMID:24844873

  14. Scanning electron microscopy combined with image processing technique: Microstructure and texture analysis of legumes and vegetables for instant meal.

    PubMed

    Pieniazek, Facundo; Messina, Valeria

    2016-04-01

    Development and innovation of new technologies are necessary especially in food quality; due that most instrumental technique for measuring quality properties involves a considerable amount of manual work. Image analysis is a technique that allows to provide objective evaluations from digitalized images that can estimate quality parameters for consumer's acceptance. The aim of the present research was to study the effect of freeze drying on the microstructure and texture of legume and vegetables using scanning electron microscopy at different magnifications' combined with image analysis. Cooked and cooked freeze dried rehydrated legumes and vegetables were analyzed individually by scanning electron microscopy at different magnifications' (250, 500, and 1000×).Texture properties were analyzed by texture analyzer and image analysis. Significant differences (P < 0.05) were obtained for image and instrumental texture parameters. A linear trend with a linear correlation was applied for instrumental and image features. Results showed that image features calculated from Grey level co-occurrence matrix at 1,000× had high correlations with instrumental features. In rice, homogeneity and contrast can be applied to evaluate texture parameters gumminess and adhesiviness; Lentils: contrast, correlation, energy, homogeneity, and entropy for hardness, adhesiviness, gumminess, and chewiness; Potato and carrots: contrast, energy, homogeneity and entropy for adhesiviness, chewiness, hardness, cohesiviness, and resilence. Results revealed that combing scanning electron microscopy with image analysis can be a useful tool to analyze quality parameters in legumes and vegetables. PMID:26789426

  15. Microbial consortium role in processing liquid waste of vegetables in Keputran Market Surabaya as organic liquid fertilizer ferti-plus

    NASA Astrophysics Data System (ADS)

    Rizqi, Fauziah; Supriyanto, Agus; Lestari, Intan; Lita Indri D., L.; Elmi Irmayanti, A.; Rahmaniyah, Fadilatur

    2016-03-01

    Many activities in this market is directly proportional to increase production of vegetables waste, especially surabaya. Therefore, in this study aims to utilize liquid waste of vegetables into liquid organic fertilizer by mixing microbial consorsium. The microbial consorsium consist of Azotobacter chrococcum, Azospirillum brasilense, Rhizobium leguminosarum, Bacillus subtilis, Bacillus megaterium, Pseudomonas putida, and Pseudomonas fluorescens. Ttreatment of microbial concentrations (5%, 10%, 15%) and the length of the incubation period (7 days, 14 days, 21 days) used in this research. The parameters used are: C/N ratio, levels of CNP, and BOD value. This study uses a standard organic fertilizer value according SNI19-7030-2004, The results show the value of C/N ratio comply with the ISO standards. C levels showed an increase during the incubation period but not compare with standards. N levels that compare with standards are microbial treatment in all group concentration except control group with an incubation period of 21 days is > 7. P levels compare with the existing standards in the group of microbe concentration of 10% and 15% during the incubation period. The value of the initial BOD liquid waste of vegetable is 790.25 mg / L, this value indicates that the waste should not go into the water body. Accordingly, the results of this study can not be used as a liquid organic fertilizer, but potentially if it is used as a natural career or build natural soil. The Building natural soil is defined as the natural ingredients that can be used to improve soil properties.

  16. A demonstration of wetland vegetation mapping in Florida from computer-processed satellite and aircraft multispectral scanner data

    NASA Technical Reports Server (NTRS)

    Butera, M. K. (Principal Investigator)

    1978-01-01

    The author has identified the following significant results. Major vegetative classes identified by the remote sensing technique were cypress swamp, pine, wetland grasses, salt grass, mixed mangrove, black mangrove, Brazilian pepper. Australian pine and melaleuca were not satisfactorily classified from LANDSAT. Aircraft scanners provided better resolution resulting in a classification of finer surface detail. An edge effect, created by the integration of diverse spectral responses within boundary elements of digital data, affected the wetlands classification. Accuracy classification for aircraft was 68% and for LANDSAT was 74%.

  17. Quantification of Listeria monocytogenes in minimally processed leafy vegetables using a combined method based on enrichment and 16S rRNA real-time PCR.

    PubMed

    Aparecida de Oliveira, Maria; Abeid Ribeiro, Eliana Guimarães; Morato Bergamini, Alzira Maria; Pereira De Martinis, Elaine Cristina

    2010-02-01

    Modern lifestyle markedly changed eating habits worldwide, with an increasing demand for ready-to-eat foods, such as minimally processed fruits and leafy greens. Packaging and storage conditions of those products may favor the growth of psychrotrophic bacteria, including the pathogen Listeria monocytogenes. In this work, minimally processed leafy vegetables samples (n = 162) from retail market from Ribeirão Preto, São Paulo, Brazil, were tested for the presence or absence of Listeria spp. by the immunoassay Listeria Rapid Test, Oxoid. Two L. monocytogenes positive and six artificially contaminated samples of minimally processed leafy vegetables were evaluated by the Most Probable Number (MPN) with detection by classical culture method and also culture method combined with real-time PCR (RTi-PCR) for 16S rRNA genes of L. monocytogenes. Positive MPN enrichment tubes were analyzed by RTi-PCR with primers specific for L. monocytogenes using the commercial preparation ABSOLUTE QPCR SYBR Green Mix (ABgene, UK). Real-time PCR assay presented good exclusivity and inclusivity results and no statistical significant difference was found in comparison with the conventional culture method (p < 0.05). Moreover, RTi-PCR was fast and easy to perform, with MPN results obtained in ca. 48 h for RTi-PCR in comparison to 7 days for conventional method. PMID:19913686

  18. Treatment of vegetable oils

    SciTech Connect

    Bessler, T.R.

    1986-05-13

    A process is described for preparing an injectable vegetable oil selected from the group consisting of soybean oil and sunflower oil and mixtures thereof which comprise: (a) first treating the vegetable oil at a temperature of 80/sup 0/C to about 130/sup 0/C with an acid clay; (b) deodorizing the vegetable oil with steam at a temperature of 220/sup 0/C to about 280/sup 0/C and applying a vacuum to remove volatilized components; (c) treating the deodorized vegetable oil, at a temperature of from about 10/sup 0/C to about 60/sup 0/C, with an acid clay to reduce the content of a member selected from the group consisting of diglycerides, tocopherol components, and trilinolenin and mixtures thereof, wherein the acid clay is added in a weight ratio to the deoderized vegetable oil of from about 1:99 to about 1:1; and (d) thereafter conducting a particulate filtration to remove a substantial portion of the acid clay from the vegetable oil, wherein the filtration is accomplished with filters having a pore size of from about 0.1 to 0.45 microns, thereby obtaining the injectable oil.

  19. Implementation of a ground truth process for development of a submerged aquatic vegetation (SAV) mapping protocol using hyperspectral imagery

    NASA Astrophysics Data System (ADS)

    Hall, Carlton R.; Bostater, Charles R., Jr.; Virnstein, Robert W.

    2006-09-01

    Protocol development for science based mapping of submerged aquatic vegetation (SAV) requires comprehensive ground truth data describing the full range of variability observed in the target. The Indian River Lagoon, Florida, extends along 250 km of the east central Florida coast adjacent to the Atlantic Ocean. The lagoon crosses the transition zone between the Caribbean and Carolinian zoogeographic provinces making it highly diverse. For large scale mapping and management of SAV four common and three uncommon species of seagrass (Tracheophyta) and three broad groups of macroalgae; red algae (Rhodophyta), green algae (Chlorophyta), and brown algae (Phaeophyta) are recognized. Based on technical and cost limitations we established twenty, 7-10 km long flight transects for collection of 1.2 m2 spatial resolution hyperspectral imagery covering the length of the lagoon. Emphasis was placed on the area near the Sebastian River and adjacent Sebastian Inlet. Twenty six 40 m long ground truth transects were established in the lagoon using 1 m2 white panels to mark each transect end. Each transect target was located in the field using high precision GPS. Transects were positioned to cover a range of depths, SAV densities, mixed and monotypic species beds, water quality conditions and general sediment types. A 3 m wide by 30 m long grid was centered on each transect to avoid spectral influences of the white targets. Water depth, species of seagrasses, estimates of vegetation cover percentage, estimates of epiphytic density, and measured canopy height were made for each 1 m2 (n=90). This target based grid arrangement allows for identification and extraction of pixel based hyperspectral signatures corresponding to individual ground truth grid cells without significant concern for rectification and registration error.

  20. Fermented Vegetables

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter is organized into several sections. The first has information on the history of vegetable fermentation research in the US, dating back to the late 1880s. A overview of commercial cucumber and sauerkraut fermentation practices follows, focusing on the US market, although there is some me...

  1. Fermented Vegetables

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The wide variety of fermented foods of the world can be classified by the materials obtained from the fermentation, such as alcohol (beer, wine), organic acid such as lactic acid and acetic acid (vegetables, dairy), carbon dioxide (bread), and amino acids or peptides from protein (fish fermentations...

  2. Novel simple process for tocopherols selective recovery from vegetable oils by adsorption and desorption with an anion-exchange resin.

    PubMed

    Hiromori, Kousuke; Shibasaki-Kitakawa, Naomi; Nakashima, Kazunori; Yonemoto, Toshikuni

    2016-03-01

    A novel and simple low-temperature process was used to recover tocopherols from a deodorizer distillate, which is a by-product of edible oil refining. The process consists of three operations: the esterification of free fatty acids with a cation-exchange resin catalyst, the adsorption of tocopherols onto an anion-exchange resin, and tocopherol desorption from the resin. No degradation of tocopherols occurred during these processes. In the tocopherol-rich fraction, no impurities such as sterols or glycerides were present. These impurities are commonly found in the product of the conventional process. This novel process improves the overall recovery ratio and the mass fraction of the product (75.9% and 51.0wt%) compared with those in the conventional process (50% and 35wt%). PMID:26471519

  3. On the potential vegetation feedbacks that enhance phosphorus availability - insights from a process-based model linking geological and ecological time scales

    NASA Astrophysics Data System (ADS)

    Buendíia, C.; Arens, S.; Hickler, T.; Higgins, S. I.; Porada, P.; Kleidon, A.

    2013-12-01

    In old and heavily weathered soils, the availability of P might be so small that the primary production of plants is limited. However, plants have evolved several mechanisms to actively take up P from the soil or mine it to overcome this limitation. These mechanisms involve the active uptake of P mediated by mycorrhiza, biotic de-occlusion through root clusters, and the biotic enhancement of weathering through root exudation. The objective of this paper is to investigate how and where these processes contribute to alleviate P limitation on primary productivity. To do so, we propose a process-based model accounting for the major processes of the carbon, water, and P cycle including chemical weathering at the global scale. We use simulation experiments to assess the relative importance of the different uptake mechanisms to alleviate P limitation on biomass production. Implementing P limitation on biomass synthesis allows the assessment of the efficiencies of biomass production across different ecosystems. We find that active P-uptake is an essential mechanism for sustaining P availability on long time scales, whereas biotic de-occlusion might serve as a buffer on time scales shorter than 10 000 yr. Although active P uptake is essential for reducing P losses by leaching, humid lowland soils reach P limitation after around 100 000 yr of soil evolution. Given the generalized modeling framework, our model results compare reasonably with observed or independently estimated patterns and ranges of P concentrations in soils and vegetation. Furthermore, our simulations suggest that P limitation might be an important driver of biomass production efficiency (the fraction of the gross primary productivity used for biomass growth), and that vegetation on older soils becomes P-limited leading to a smaller biomass production efficiency. With this study, we provide a theoretical basis for investigating the responses of terrestrial ecosystems to P availability linking geological and

  4. Protein structural changes during processing of vegetable feed ingredients used in swine diets: implications for nutritional value.

    PubMed

    Salazar-Villanea, S; Hendriks, W H; Bruininx, E M A M; Gruppen, H; van der Poel, A F B

    2016-06-01

    Protein structure influences the accessibility of enzymes for digestion. The proportion of intramolecular β-sheets in the secondary structure of native proteins has been related to a decrease in protein digestibility. Changes to proteins that can be considered positive (for example, denaturation and random coil formation) or negative (for example, aggregation and Maillard reactions) for protein digestibility can occur simultaneously during processing. The final result of these changes on digestibility seems to be a counterbalance of the occurrence of each phenomenon. Occurrence of each phenomenon depends on the conditions applied, but also on the source and type of the protein that is processed. The correlation between denaturation enthalpy after processing and protein digestibility seems to be dependent on the protein source. Heat seems to be the processing parameter with the largest influence on changes in the structure of proteins. The effect of moisture is usually limited to the simultaneous application of heat, but increasing level of moisture during processing usually increases structural changes in proteins. The effect of shear on protein structure is commonly studied using extrusion, although the multifactorial essence of this technology does not allow disentanglement of the separate effects of each processing parameter (for example, heat, shear, moisture). Although most of the available literature on the processing of feed ingredients reports effects on protein digestibility, the mechanisms that explain these effects are usually lacking. Clarifying these mechanisms could aid in the prediction of the nutritional consequences of processing conditions. PMID:27356771

  5. Applying process mapping and analysis as a quality improvement strategy to increase the adoption of fruit, vegetable, and water breaks in Australian primary schools.

    PubMed

    Biggs, Janice S; Farrell, Louise; Lawrence, Glenda; Johnson, Julie K

    2014-03-01

    Over the past decade, public health policy in Australia has prioritized the prevention and control of obesity and invested in programs that promote healthy eating-related behaviors, which includes increasing fruit and vegetable consumption in children. This article reports on a study that used process mapping and analysis as a quality improvement strategy to improve the delivery of a nutrition primary prevention program delivered in primary schools in New South Wales, Australia. Crunch&Sip® has been delivered since 2008. To date, adoption is low with only 25% of schools implementing the program. We investigated the cause of low adoption and propose actions to increase school participation. We conducted semistructured interviews with key stakeholders and analyzed the process of delivering Crunch&Sip to schools. Interviews and process mapping and analysis identified a number of barriers to schools adopting the program. The analyses identified the need to simplify and streamline the process of delivering the program to schools and introduce monitoring and feedback loops to track ongoing participation. The combination of stakeholder interviews and process mapping and analysis provided important practical solutions to improving program delivery and also contributed to building an understanding of factors that help and hinder program adoption. The insight provided by this analysis helped identify usable routine measures of adoption, which were an improvement over those used in the existing program plan. This study contributed toward improving the quality and efficiency of delivering a health promoting program to work toward achieving healthy eating behaviors in children. PMID:24163325

  6. Effects of combined pressure and temperature on enzymes related to quality of fruits and vegetables: from kinetic information to process engineering aspects.

    PubMed

    Ludikhuyze, L; Van Loey, A; Indrawati; Smout, C; Hendrickx, M

    2003-01-01

    Throughout the last decade, high pressure technology has been shown to offer great potential to the food processing and preservation industry in delivering safe and high quality products. Implementation of this new technology will be largely facilitated when a scientific basis to assess quantitatively the impact of high pressure processes on food safety and quality becomes available. Besides, quantitative data on the effects of pressure and temperature on safety and quality aspects of foods are indispensable for design and evaluation of optimal high pressure processes, i.e., processes resulting in maximal quality retention within the constraints of the required reduction of microbial load and enzyme activity. Indeed it has to be stressed that new technologies should deliver, apart from the promised quality improvement, an equivalent or preferably enhanced level of safety. The present paper will give an overview from a quantitative point of view of the combined effects of pressure and temperature on enzymes related to quality of fruits and vegetables. Complete kinetic characterization of the inactivation of the individual enzymes will be discussed, as well as the use of integrated kinetic information in process engineering. PMID:14653494

  7. Comparison of four commercial DNA extraction kits for PCR detection of Listeria monocytogenes, Salmonella, Escherichia coli O157:H7, and Staphylococcus aureus in fresh, minimally processed vegetables.

    PubMed

    Elizaquível, P; Aznar, R

    2008-10-01

    Four commercial DNA extraction methods, PrepMan Ultra (Applied Biosystems), InstaGene Matrix (BioRad), DNeasy Tissue kit (Qiagen), and UltraClean (MoBio), were tested for PCR detection of Listeria monocytogenes, Escherichia coli O157: H7, Salmonella, and Staphylococcus aureus in fresh, minimally processed vegetables. For comparative purposes, sensitivity assays with specific PCRs were carried out after DNA extraction with the four methods in green pepper, broccoli, and onion artificially inoculated with the four pathogens separately. As confirmed by statistical analysis, the DNeasy Tissue kit rendered the highest sensitivity values in the three matrices assayed for Salmonella, L. monocytogenes, and E. coli O157:H7 and in onion for S. aureus. Despite being the most expensive of the methods compared, the DNeasy Tissue Kit can be successfully applied for any of the four most commonly studied pathogens, thus saving time and overall reducing the cost of the analysis. PMID:18939762

  8. Application of satellite data and LARS's data processing techniques to mapping vegetation of the Dismal Swamp. M.S. Thesis - Old Dominion Univ.

    NASA Technical Reports Server (NTRS)

    Messmore, J. A.

    1976-01-01

    The feasibility of using digital satellite imagery and automatic data processing techniques as a means of mapping swamp forest vegetation was considered, using multispectral scanner data acquired by the LANDSAT-1 satellite. The site for this investigation was the Dismal Swamp, a 210,000 acre swamp forest located south of Suffolk, Va. on the Virginia-North Carolina border. Two basic classification strategies were employed. The initial classification utilized unsupervised techniques which produced a map of the swamp indicating the distribution of thirteen forest spectral classes. These classes were later combined into three informational categories: Atlantic white cedar (Chamaecyparis thyoides), Loblolly pine (Pinus taeda), and deciduous forest. The subsequent classification employed supervised techniques which mapped Atlantic white cedar, Loblolly pine, deciduous forest, water and agriculture within the study site. A classification accuracy of 82.5% was produced by unsupervised techniques compared with 89% accuracy using supervised techniques.

  9. Experimental scale and dimensionality requirements for reproducing and studying coupled land-atmosphere-vegetative processes in the intermediate scale laboratory settings

    NASA Astrophysics Data System (ADS)

    Trautz, Andrew; Illangasekare, Tissa; Rodriguez-Iturbe, Ignacio; Helmig, Rainer; Heck, Katharina

    2016-04-01

    Past investigations of coupled land-atmosphere-vegetative processes have been constrained to two extremes, small laboratory bench-scale and field scale testing. In recognition of the limitations of studying the scale-dependency of these fundamental processes at either extreme, researchers have recently begun to promote the use of experimentation at intermediary scales between the bench and field scales. A requirement for employing intermediate scale testing to refine heat and mass transport theory regarding land-atmosphere-vegetative processes is high spatial-temporal resolution datasets generated under carefully controlled experimental conditions in which both small and field scale phenomena can be observed. Field experimentation often fails these criteria as a result of sensor network limitations as well as the natural complexities and uncertainties introduced by heterogeneity and constantly changing atmospheric conditions. Laboratory experimentation, which is used to study three-dimensional (3-D) processes, is often conducted in 2-D test systems as a result of space, instrumentation, and cost constraints. In most flow and transport problems, 2-D testing is not considered a serious limitation because the bypassing of flow and transport due to geo-biochemical heterogeneities can still be studied. Constraining the study of atmosphere-soil-vegetation interactions to 2-D systems introduces a new challenge given that the soil moisture dynamics associated with these interactions occurs in three dimensions. This is an important issue that needs to be addressed as evermore intricate and specialized experimental apparatuses like the climate-controlled wind tunnel-porous media test system at CESEP are being constructed and used for these types of studies. The purpose of this study is to therefore investigate the effects of laboratory experimental dimensionality on observed soil moisture dynamics in the context of bare-soil evaporation and evapotranspiration

  10. Effects of Holocene vegetation change on soils across the forest-grassland transition, northern Minnesota, and implications for erosion processes

    NASA Astrophysics Data System (ADS)

    Mason, Joseph; Kasmerchak, Chase; Keita, Hawa; Liang, Mengyu; Gruley, Kristine

    2016-04-01

    Boundaries between forest and grassland in the midlatitudes and their shifts in response to Holocene climatic change, provide opportunities to detect effects of life on landscapes. In northern Minnesota, USA, paleoecological research has documented that grassland and/or savanna expanded eastward in the dry early to middle Holocene. In the late Holocene, forest cover expanded westward at the expense of savanna and grassland. We studied soils at 20 sites spanning the forest-grassland transition. A dramatic change in soil morphology coincides approximately, though not exactly, with that transition as recorded in 1870s-1880s land surveys, suggesting that soils change rapidly in response to forest expansion (we are attempting to constrain the timescale of response through radiocarbon dating of deep soil organic matter in which stable C isotopes record past presence of grassland). The key changes from grassland to forest are loss of organic matter below a thin surface A horizon and greatly enhanced mobility and downward translocation of clay - particularly smectite - in forest soils. This results in upper soil horizons that have relatively low smectite content and low microaggregate stability (as detected through laser diffraction analysis of aggregate disintegration in laboratory experiments), especially below the thin A horizon. The best explanation for this change appears to involve differences in how OM is added to and accumulated in the soil under forest and grassland; soil acidity and base saturation change more gradually eastward along a gradient more likely to reflect climate than vegetation. Evidence of bioturbation (especially gopher burrowing) is much more common at former grassland sites. In addition to mixing OM downward in the soil, burrowing moves detrital carbonates upward, probably enhancing OM accumulation and aggregate stability. Research on geomorphic response to Holocene climatic change in the Midwestern US has often emphasized higher potential

  11. Determination of the energy potential of gases produced in the pyrolysis processes of the vegetal carbon manufacture industry.

    PubMed

    Gañan, J; González, J F; González-García, C M; Cuerda-Correa, E M; Macías-García, A

    2006-03-01

    In this work, a pyrolysis plant located in Valverde de Leganes, Badajoz (SW Spain) was studied. At present, only the solid phase obtained by pyrolysis finds an application as domestic fuel. In order to analyze the feasibility of a further energetic exploitation of the plant under study, the gases flowing through the chimneys were collected at different times throughout the pyrolysis process. Next, they were characterized and quantified by gas chromatography, the energy potential of each of the gases being determined. According to the results obtained in this study, a total energy potential of 5.6 x 10(7) MJ (i.e., 1.78 MW(t)) might be generated yearly. Hence, considering an overall process yield equal to 20%, up to 358 KW(e) would be produced. This power would supply enough electric energy to the industry, the remaining being added to the common electric network. PMID:15953721

  12. Isotopic Composition of Atmospheric Mercury in China: New Evidence for Sources and Transformation Processes in Air and in Vegetation.

    PubMed

    Yu, Ben; Fu, Xuewu; Yin, Runsheng; Zhang, Hui; Wang, Xun; Lin, Che-Jen; Wu, Chuansheng; Zhang, Yiping; He, Nannan; Fu, Pingqing; Wang, Zifa; Shang, Lihai; Sommar, Jonas; Sonke, Jeroen E; Maurice, Laurence; Guinot, Benjamin; Feng, Xinbin

    2016-09-01

    The isotopic composition of atmospheric total gaseous mercury (TGM) and particle-bound mercury (PBM) and mercury (Hg) in litterfall samples have been determined at urban/industrialized and rural sites distributed over mainland China for identifying Hg sources and transformation processes. TGM and PBM near anthropogenic emission sources display negative δ(202)Hg and near-zero Δ(199)Hg in contrast to relatively positive δ(202)Hg and negative Δ(199)Hg observed in remote regions, suggesting that different sources and atmospheric processes force the mass-dependent fractionation (MDF) and mass-independent fractionation (MIF) in the air samples. Both MDF and MIF occur during the uptake of atmospheric Hg by plants, resulting in negative δ(202)Hg and Δ(199)Hg observed in litter-bound Hg. The linear regression resulting from the scatter plot relating the δ(202)Hg to Δ(199)Hg data in the TGM samples indicates distinct anthropogenic or natural influences at the three study sites. A similar trend was also observed for Hg accumulated in broadleaved deciduous forest foliage grown in areas influenced by anthropogenic emissions. The relatively negative MIF in litter-bound Hg compared to TGM is likely a result of the photochemical reactions of Hg(2+) in foliage. This study demonstrates the diagnostic stable Hg isotopic composition characteristics for separating atmospheric Hg of different source origins in China and provides the isotopic fractionation clues for the study of Hg bioaccumulation. PMID:27485289

  13. Recovery times of riparian vegetation

    NASA Astrophysics Data System (ADS)

    Vesipa, R.; Camporeale, C.; Ridolfi, L.

    2016-04-01

    Riparian vegetation is a key element in a number of processes that determine the ecogeomorphological features of the river landscape. Depending on the river water stage fluctuations, vegetation biomass randomly switches between growth and degradation phases and exhibits relevant temporal variations. A full understanding of vegetation dynamics is therefore only possible if the hydrological stochastic forcing is considered. In this vein, we focus on the recovery time of vegetation, namely the typical time taken by vegetation to recover a well-developed state starting from a low biomass value (induced, for instance, by an intense flood). The analytical expression of the plot-dependent recovery time is given, the role of hydrological and biological parameters is discussed, and the impact of river-induced randomness is highlighted. Finally, the effect of man-induced hydrological changes (e.g., river damming or climate changes) is explored.

  14. Effects of acidic deposition on nutrient uptake, nutrient cycling and growth processes of vegetation in the spruce-fir ecosystem

    SciTech Connect

    McLaughlin, S.B.; Garten, C.T.; Wullschleger, S.D.

    1996-10-16

    This report summarizes progress in three years of field research designed to evaluate biological and chemical indicators of the current and future health of the Southern Appalachian spruce-fir ecosystem. The emphasis of this research has been on the identification and understanding of mechanisms through which current levels of acidic deposition are impacting ecosystem processes. The identification of these principal mechanisms and key biological indicators of change was designed to improve our capabilities to detect, monitor, and assess the effects of air quality regulations and attendant future air quality changes on ecosystem response. Individual research tasks focused on the following research areas: (1) the significance of foliar uptake of atmospheric sources of nitrogen in relationship to plant utilization of N from available soil reserves; (2) linkages between atmospheric inputs to the soil surface, solution chemistry, and decomposition in the upper organic soil horizons; (3) effects of soil solution chemistry on uptake of cations and aluminum by fine roots; and (4) the effects of varying rates of calcium supply on carbon metabolism of Fraser fir and red spruce, and the relationship between calcium levels in wood cells and integrity of wood formed in bole and branches. Each of the individual tasks was designed to focus upon a mechanism or process that we consider critical to understanding chemical and biological linkages. These linkages will be important determinants in understanding the basis of past and potential future responses of the high elevation Southern Appalachian Forest to acidic deposition and other co-occurring environmental stresses. This report contains (1) background and rationale for the research undertaken in 1992-94; (2) a summary of principal research findings; (3) publications from this research; and (4) characterization of data sets produced by this research which will be the basis of future research, analyses and/or publications.

  15. Assessment of PAH dissipation processes in large-scale outdoor mesocosms simulating vegetated road-side swales.

    PubMed

    Leroy, M C; Legras, M; Marcotte, S; Moncond'huy, V; Machour, N; Le Derf, F; Portet-Koltalo, F

    2015-07-01

    Biofilters have been implemented in urban areas due to their ability to improve road runoff quality. However, little is known about the role of soil microorganisms and plants on pollutant remediation in planted swales. Therefore, four large-scale outdoor mesocosms were built and co-contaminated with metals and model polycyclic aromatic hydrocarbons (PAHs) (phenanthrene (Phen), pyrene (Pyr) and benzo[a]pyrene (BaP)), to better understand the complex functioning of swale-like environments. Three macrophyte plant species were tested for enhanced remediation of PAHs: Juncus effusus, Iris pseudacorus, Phalaris arundinacea and a grass mix. Long-term dynamics of PAHs in water outflow and soil was studied. Results showed that only 0.07 to 0.22% of total PAHs were released in water outflow after one year. Two years after contamination, soil sample analyses showed a dissipation of 99.6% for Phen and 99.4% for Pyr whatever the mesocosm considered and ranging from 75.5 to 91% for BaP, depending on plant species. Furthermore, dissipation time-courses may be described by a biphasic process. Experiments showed that the grass mix facilitated BaP long-term biodegradation. Grass appeared also to be the best filter for suspended solids because of its dense rhizosphere, which prevents the transfer of BaP to groundwater. PMID:25813967

  16. Combining livestock production information in a process-based vegetation model to reconstruct the history of grassland management

    NASA Astrophysics Data System (ADS)

    Chang, Jinfeng; Ciais, Philippe; Herrero, Mario; Havlik, Petr; Campioli, Matteo; Zhang, Xianzhou; Bai, Yongfei; Viovy, Nicolas; Joiner, Joanna; Wang, Xuhui; Peng, Shushi; Yue, Chao; Piao, Shilong; Wang, Tao; Hauglustaine, Didier A.; Soussana, Jean-Francois; Peregon, Anna; Kosykh, Natalya; Mironycheva-Tokareva, Nina

    2016-06-01

    Grassland management type (grazed or mown) and intensity (intensive or extensive) play a crucial role in the greenhouse gas balance and surface energy budget of this biome, both at field scale and at large spatial scale. However, global gridded historical information on grassland management intensity is not available. Combining modelled grass-biomass productivity with statistics of the grass-biomass demand by livestock, we reconstruct gridded maps of grassland management intensity from 1901 to 2012. These maps include the minimum area of managed vs. maximum area of unmanaged grasslands and the fraction of mown vs. grazed area at a resolution of 0.5° by 0.5°. The grass-biomass demand is derived from a livestock dataset for 2000, extended to cover the period 1901-2012. The grass-biomass supply (i.e. forage grass from mown grassland and biomass grazed) is simulated by the process-based model ORCHIDEE-GM driven by historical climate change, rising CO2 concentration, and changes in nitrogen fertilization. The global area of managed grassland obtained in this study increases from 6.1 × 106 km2 in 1901 to 12.3 × 106 km2 in 2000, although the expansion pathway varies between different regions. ORCHIDEE-GM also simulated augmentation in global mean productivity and herbage-use efficiency over managed grassland during the 20th century, indicating a general intensification of grassland management at global scale but with regional differences. The gridded grassland management intensity maps are model dependent because they depend on modelled productivity. Thus specific attention was given to the evaluation of modelled productivity against a series of observations from site-level net primary productivity (NPP) measurements to two global satellite products of gross primary productivity (GPP) (MODIS-GPP and SIF data). Generally, ORCHIDEE-GM captures the spatial pattern, seasonal cycle, and interannual variability of grassland productivity at global scale well and thus is

  17. Single-phase and two-phase anaerobic digestion of fruit and vegetable waste: Comparison of start-up, reactor stability and process performance

    SciTech Connect

    Ganesh, Rangaraj; Torrijos, Michel; Sousbie, Philippe; Lugardon, Aurelien; Steyer, Jean Philippe; Delgenes, Jean Philippe

    2014-05-01

    Highlights: • Single-phase and two-phase systems were compared for fruit and vegetable waste digestion. • Single-phase digestion produced a methane yield of 0.45 m{sup 3} CH{sub 4}/kg VS and 83% VS removal. • Substrate solubilization was high in acidification conditions at 7.0 kg VS/m{sup 3} d and pH 5.5–6.2. • Energy yield was lower by 33% for two-phase system compared to the single-phase system. • Simple and straight-forward operation favored single phase process over two-phase process. - Abstract: Single-phase and two-phase digestion of fruit and vegetable waste were studied to compare reactor start-up, reactor stability and performance (methane yield, volatile solids reduction and energy yield). The single-phase reactor (SPR) was a conventional reactor operated at a low loading rate (maximum of 3.5 kg VS/m{sup 3} d), while the two-phase system consisted of an acidification reactor (TPAR) and a methanogenic reactor (TPMR). The TPAR was inoculated with methanogenic sludge similar to the SPR, but was operated with step-wise increase in the loading rate and with total recirculation of reactor solids to convert it into acidification sludge. Before each feeding, part of the sludge from TPAR was centrifuged, the centrifuge liquid (solubilized products) was fed to the TPMR and centrifuged solids were recycled back to the reactor. Single-phase digestion produced a methane yield of 0.45 m{sup 3} CH{sub 4}/kg VS fed and VS removal of 83%. The TPAR shifted to acidification mode at an OLR of 10.0 kg VS/m{sup 3} d and then achieved stable performance at 7.0 kg VS/m{sup 3} d and pH 5.5–6.2, with very high substrate solubilization rate and a methane yield of 0.30 m{sup 3} CH{sub 4}/kg COD fed. The two-phase process was capable of high VS reduction, but material and energy balance showed that the single-phase process was superior in terms of volumetric methane production and energy yield by 33%. The lower energy yield of the two-phase system was due to the loss of

  18. Linking carbon-water- and nitrogen fluxes at forest ecosystems throughout Europe with a coupled soil-vegetation process model "LandscapeDNDC"

    NASA Astrophysics Data System (ADS)

    Molina Herrera, Saul; Grote, Rüdiger; Haas, Edwin; Kiese, Ralf; Butterbach-Bahl, Klaus

    2013-04-01

    2), accuracy (r2eff) and agreement (RMSPEn) while for reproducing daily NEE and ET as well as soil moisture was accompanied by a good statistical precision and agreement. In addition, beside C fixation also simulated C allocation into different vegetation compartments agreed well with measured data on biomass development and vegetation structure. Also soil respiration and N2O emissions agreed well with field observations. Soil respiration was driven by GPP and the rates of N2O fluxes depended on soil ecosystem properties and were influenced by litter C/N inputs and weather conditions. In conclusion by use of general tree species parameterizations LandscapeDNDC was capable to simulate and capture impacts of a multitude of environmental drivers on forest ecosystem C-, N-, water dynamics, as well as linking above - and belowground processes across various sites in Europe. Nevertheless, the quality of measured data (e.g. spatial representation, time resolution) as well as the existing description of ecosystem processes in the model should be considered when evaluating the capability of process based models to be used for evaluation of biogeochemical ecosystem functioning.

  19. Recovery times of riparian vegetation

    NASA Astrophysics Data System (ADS)

    Vesipa, Riccardo; Camporeale, Carlo; Ridolfi, Luca

    2016-04-01

    Riparian vegetation is a key element in a number of processes that determine the eco-geomorphological features of the river landscape. Depending on the river water stage fluctuations, vegetation biomass randomly switches between growth and decay phases, and its biomass exhibits relevant temporal variations. A full understanding of vegetation dynamics is therefore only possible if the hydrological stochastic forcing is considered. In this vein, we focus on the recovery time of vegetation, namely the typical time taken by vegetation to recover a health state starting from a low biomass value (induced, for instance, by an intense flood). The minimalistic stochastic modeling approach is used for describing vegetation dynamics (i.e., the noise-driven alternation of growth and decay phases). The recovery time of biomass is then evaluated according to the theory of the mean first passage time in systems driven by dichotomous noise. The effect of the main hydrological and biological parameters on the vegetation recovery was studied, and the dynamics along the riparian transect was described in details. The effect of climate change and human interventions (e.g., river damming) was also investigated. We found that: (i) the oscillations of the river stage delay the recovery process (up to one order of magnitude, with respect to undisturbed conditions); (ii) hydrological/biological alterations (due to climate change, damming, exotic species invasion) modify the timescales of the recovery. The result provided can be a useful tool for the management of the river. They open the way to the estimation of: (i) the recovery time of vegetation after devastating floods, clear cutting or fires and; (ii) the timescale of the vegetation response to hydrological and biological alterations.

  20. Surface properties of the Ni-silica gel catalyst precursors for the vegetable oil hydrogenation process: N2 sorption and XPS studies

    NASA Astrophysics Data System (ADS)

    Nikolova, D.; Krstić, J.; Spasov, L.; Simeonov, D.; Lončarević, D.; Stefanov, Pl.; Jovanović, D.

    2011-12-01

    The effect of the type of the silica gel pore structure on the surface properties of the Ni-silica gel catalyst precursors for the vegetable oil hydrogenation process has been examined applying N2 sorption and X-ray photoelectron spectroscopy techniques. The nickel catalyst precursors with identical composition (SiO2/Ni = 1.0) has been synthesized by precipitation of Ni(NO3)2 · 6H2O solution with Na2CO3 solution on the three types of silica gel with different pore structures. It is shown that the usage of the silica gel supports with different texture as source of SiO2 causes different location of Ni-species into the support pores and on the external surface area. The XPS data confirm the formation of surface species with different strength of interaction and different dispersion. These surface characteristics of the precursors will predetermine the formation of the active nickel metallic phase as well as the mass transfer of the reactants and products to and from the catalytic sites.

  1. The Influence of Climate Variation and Change on Structure and Processes in Nearshore Vegetated Communities of Puget Sound and other Northwest Estuaries

    SciTech Connect

    Thom, Ronald M.; Borde, Amy B.; Blanton, Susan L.; Woodruff, Dana L.; Williams, Gregory D.

    2001-02-14

    We have been investigating the potential for variations in ocean temperature and carbon dioxide to affect nearshore vegetated communities in the Pacific Northwest. Experimental studies as well as long-term monitoring suggest that these communities will respond to climate change and that alterations in their functions may impact fisheries resources. This paper addresses the effects of sea level rise on coastal communities; temperature variations on eelgrass; carbon dioxide-enriched seawater on photosynthetic rates of mudflats, seagrasses, and bull kelp; and of increased climate variability on primary production. Conclusions show there is a clear need to focus investigations on the potential effects of a warmer and CO2-rich environment on Puget Sound's nearshore ecosystem. Experimental data as well as filed studies strongly indicate that temperature is a major factor controlling benthic primary production, respiration and community production in Pacific Northwest estuarine ecosystems. A shift in temperature will predictably affect these processes. The actual amount of effect, the complexities of change and the ultimate impact on fisheries resources are unquantified and highly speculative at this time.

  2. [Review of dynamic global vegetation models (DGVMs)].

    PubMed

    Che, Ming-Liang; Chen, Bao-Zhang; Wang, Ying; Guo, Xiang-Yun

    2014-01-01

    Dynamic global vegetation model (DGVM) is an important and efficient tool for study on the terrestrial carbon circle processes and vegetation dynamics. This paper reviewed the development history of DGVMs, introduced the basic structure of DGVMs, and the outlines of several world-widely used DGVMs, including CLM-DGVM, LPJ, IBIS and SEIB. The shortages of the description of dynamic vegetation mechanisms in the current DGVMs were proposed, including plant functional types (PFT) scheme, vegetation competition, disturbance, and phenology. Then the future research directions of DGVMs were pointed out, i. e. improving the PFT scheme, refining the vegetation dynamic mechanism, and implementing a model inter-comparison project. PMID:24765870

  3. Monitoring vegetation phenology using MODIS

    USGS Publications Warehouse

    Zhang, Xiayong; Friedl, Mark A.; Schaaf, Crystal B.; Strahler, Alan H.; Hodges, John C.F.; Gao, Feng; Reed, Bradley C.; Huete, Alfredo

    2003-01-01

    Accurate measurements of regional to global scale vegetation dynamics (phenology) are required to improve models and understanding of inter-annual variability in terrestrial ecosystem carbon exchange and climate–biosphere interactions. Since the mid-1980s, satellite data have been used to study these processes. In this paper, a new methodology to monitor global vegetation phenology from time series of satellite data is presented. The method uses series of piecewise logistic functions, which are fit to remotely sensed vegetation index (VI) data, to represent intra-annual vegetation dynamics. Using this approach, transition dates for vegetation activity within annual time series of VI data can be determined from satellite data. The method allows vegetation dynamics to be monitored at large scales in a fashion that it is ecologically meaningful and does not require pre-smoothing of data or the use of user-defined thresholds. Preliminary results based on an annual time series of Moderate Resolution Imaging Spectroradiometer (MODIS) data for the northeastern United States demonstrate that the method is able to monitor vegetation phenology with good success.

  4. Evaluating controls on coupled hydrologic and vegetation dynamics in a humid continental climate watershed using a subsurface-land surface processes model

    NASA Astrophysics Data System (ADS)

    Shen, Chaopeng; Niu, Jie; Phanikumar, Mantha S.

    2013-05-01

    Understanding key controls on hydrologic dynamics is important for effectively allocating resources for data collection, reducing model dimensionality, and making modeling decisions. This work seeks to elucidate the physical factors responsible for the observed hydrologic patterns of a watershed in Michigan using an integrated hydrologic model, Process-based Adaptive Watershed Simulator and Community Land Model (PAWS+CLM). The model is tested using observed data for streamflows, soil temperature, groundwater table depths, and satellite-based observations of evapotranspiration (ET) and leaf area index (LAI). Numerical experiments are carried out to lump the effects of key controls, including land use types, nitrogen levels, groundwater redistribution, and soil texture, into different process indices. Using analysis of variance (ANOVA), we quantitatively determine the strengths of these controls on ET, net primary production (NPP), and other important variables. Groundwater flow is found to be the major control on runoff and infiltration, with soil texture ranking next, while vegetation type and nitrogen levels are found to dominate NPP, top soil temperature, and transpiration. Soil texture and groundwater are found to have comparable influence on soil moisture, which is in agreement with analysis of field data in the literature. All controls are found to colimit ET, which serves as the nexus for ecosystem-hydrology interactions. From the simulation results, we find that nitrogen significantly controls transpiration, through which it influences other hydrologic fluxes. While there is room for improving descriptions of the nitrogen cycle in the current version of CLM, these novel results call for an understanding of the interplay between hydrology and biogeochemistry. Additional analysis shows that the relative strengths of the controls examined in this work are fairly robust with respect to changes in parameters and spatial resolution.

  5. Emergence of river dynamics through changing vegetation patterns

    NASA Astrophysics Data System (ADS)

    van Oorschot, Mijke; Kleinhans, Maarten; Middelkoop, Hans; Geerling, Gertjan

    2016-04-01

    Riparian vegetation interacts with morphodynamic processes in rivers to create distinct habitat mosaics supporting a large biodiversity. The aim of our work is to quantitatively investigate the emergent patterns in vegetation and river morphology at the river reach scale by dynamically modelling the processes and their interactions. Here, we coupled an advanced morphodynamic model to a novel dynamic riparian vegetation model to study the interaction between vegetation and morphodynamics. Vegetation colonizes bare substrate within the seed dispersal window, passes several growth stages with different properties and can die through flooding, desiccation, uprooting, scour or burial. We have compared river morphology and vegetation patterns of scenarios without vegetation, with static vegetation that does not grow or die and several dynamic vegetation scenarios with a range of vegetation strategies and eco-engineering properties. Results show that dynamic vegetation has a decreased lateral migration of meander bends and maintains its active meandering behavior as opposed to the scenarios without vegetation and with static vegetation. Also the patterns in vegetation and fluvial morphology and the vegetation age distribution mostly resemble the natural situation when compared to aerial photos of the study area. We find that river dynamics, specifically sinuosity and sediment transport, are very sensitive to vegetation properties that determine vegetation density, settlement location and survival. Future work will include the effects of invasive species, addition of silt and the effect of various river management strategies.

  6. Research in remote sensing of vegetation

    NASA Technical Reports Server (NTRS)

    Schrumpf, Barry J.; Ripple, William J.; Isaacson, Dennis L.

    1988-01-01

    The research topics undertaken were primarily selected to further the understanding of fundamental relationships between electromagnetic energy measured from Earth orbiting satellites and terrestrial features, principally vegetation. Vegetation is an essential component in the soil formation process and the major factor in protecting and holding soil in place. Vegetation plays key roles in hydrological and nutrient cycles. Awareness of improvement or deterioration in the capacity of vegetation and the trends that those changes may indicate are, therefore, critical detections to make. A study of the relationships requires consideration of the various portions of the electromagnetic spectrum; characteristics of detector system; synergism that may be achieved by merging data from two or more detector systems or multiple dates of data; and vegetational characteristics. The vegetation of Oregon is sufficiently diverse as to provide ample opportunity to investigate the relationships suggested above several vegetation types.

  7. Powdered hide model for vegetable tanning

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Powdered hide samples for this initial study of vegetable tanning were prepared from hides that were dehaired by a typical sulfide or oxidative process, and carried through the delime/bate step of a tanning process. In this study, we report on interactions of the vegetable tannin, quebracho with th...

  8. A multiplex RTi-PCR reaction for simultaneous detection of Escherichia coli O157:H7, Salmonella spp. and Staphylococcus aureus on fresh, minimally processed vegetables.

    PubMed

    Elizaquível, Patricia; Aznar, Rosa

    2008-08-01

    In this work, a new multiplex single-tube real-time PCR approach is presented for the detection of Escherichia coli O157:H7, Salmonella spp. and Staphylococcus aureus, three of the more frequent food-borne bacterial pathogens that are usually investigated in a variety of food matrices. The study includes the design and specificity testing, of a new primer and probe specific for Salmonella spp. Reaction conditions were adjusted for the simultaneous amplification and detection of specific fragments in the beta-glucuronidase (uidA, E. coli) and Thermonulease (nuc, Sta. aureus) genes, and in the replication origin sequence (oriC, Salmonella spp.). Melting-curve analysis using a SYBR Green I RTi-PCR approach showed characteristic T(m) values demonstrating the specific and efficient amplification of the three fragments. Subsequently, a TaqMan RTi-PCR approach was settled, using FAM, NED and VIC fluorescently labelled specific probes for an automated detection. It was equally sensitive than uniplex RTi-PCR reactions in Sta. aureus and E. coli O157:H7, using same amounts of purified DNA, and allowed detection of 10 genome equivalents in the presence of 10(2) or 10(4) genome equivalents of the other two pathogens. Finally, it was tested in artificially inoculated fresh, minimally processed vegetables, revealing a sensitivity of 10(3)CFUg(-1) each of these pathogens in direct detection, following DNA extraction with DNeasy Tissue Kit (Qiagen). The multiplex RTi-PCR developed scored the sensitivity recognised for PCR in food and it allows a high-throughput and automation, thus it is promising as a rapid and cost-effective test for the food industry. PMID:18541170

  9. Glyphosate’s impact on vegetative growth in leafy spurge identifies molecular processes and hormone cross-talk associated with increased branching

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leafy spurge (Euphorbia esula) is a perennial weed that is considered glyphosate tolerant. Tolerance is partly attributed to escape through establishment of new vegetative shoots from an abundance of underground adventitious buds. Sub-lethal concentrations of foliar applied glyphosate resulted in ne...

  10. Experimental investigation of the effect of vegetation on soil, sediment erosion, and salt transport processes in the Upper Colorado River Basin Mancos Shale formation, Price, Utah, USA.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Because of concerns about salinity in the Colorado River, this study focused on saline and sodic soils associated with the Mancos Shale formation with the objective of investigating mechanisms driving sediment yield and salinity loads and the role of vegetation in altering soil chemistry in the Pric...

  11. The Change4Life Convenience Store Programme to Increase Retail Access to Fresh Fruit and Vegetables: A Mixed Methods Process Evaluation

    PubMed Central

    Adams, Jean; Halligan, Joel; Burges Watson, Duika; Ryan, Vicky; Penn, Linda; Adamson, Ashley J.; White, Martin

    2012-01-01

    Background Consumption of fruit and vegetables is important for health, but is often lower than recommended and tends to be socio-economically patterned with lower consumption in more deprived groups. In 2008, the English Department of Health introduced the Change4Life convenience store programme. This aimed to increase retail access to fresh fruit and vegetables in deprived, urban areas by providing existing convenience stores with a range of support and branded point-of-sale materials and equipment. Methods We undertook a mixed-methods study of the Change4Life convenience store programme in the North East of England around two years after initial implementation. Store mapping (n = 87; 100% stores) and systematic in-store observations (n = 74; 85% stores) provided information on intervention fidelity; the variety, purchase price and quality of fresh fruit and vegetables on sale; and purchase price compared to a major supermarket. Ten qualitative interviews with a purposive sample of retailers and other professionals explored experiences of the intervention and provided further insight on quantitative results. Results Intervention stores were primarily located in socio-economically disadvantaged areas. Fidelity, in terms of presence of branded materials and equipment, was low and much was not being used as intended. Fresh fruit and vegetables on sale were of high quality and had a purchase price around 10% more than comparable products at a major supermarket. Interviewees were supportive of the health improvement aim of the intervention. Retailers were appreciative of part-funding for chill cabinets and free point-of-sale materials. The intervention suffered from: poor initial and on-going communication between the intervention delivery team and retailers; poor availability of replacement point-of-sale materials; and failure to cement intended links with health workers and community organisations. Conclusions Overall, intervention fidelity was low and the

  12. Microbial carbon recycling: an underestimated process controlling soil carbon dynamics - Part 2: A C3-C4 vegetation change field labelling experiment

    NASA Astrophysics Data System (ADS)

    Basler, A.; Dippold, M.; Helfrich, M.; Dyckmans, J.

    2015-11-01

    The mean residence times (MRT) of different compound classes of soil organic matter (SOM) do not match their inherent recalcitrance to decomposition. One reason for this is the stabilization within the soil matrix, but recycling, i.e. the reuse of "old" organic material to form new biomass may also play a role as it uncouples the residence times of organic matter from the lifetime of discrete molecules in soil. We analysed soil sugar dynamics in a natural 30-year old labelling experiment after a wheat-maize vegetation change to determine the extent of recycling and stabilization by assessing differences in turnover dynamics between plant and microbial-derived sugars: while plant-derived sugars are only affected by stabilization processes, microbial sugars may be subject to both, stabilization and recycling. To disentangle the dynamics of soil sugars, we separated different density fractions (free particulate organic matter (fPOM), light occluded particulate organic matter (≤ 1.6 g cm-3; oPOM1.6), dense occluded particulate organic matter (≤ 2 g cm-3; oPOM2) and mineral-associated organic matter (> 2 g cm-3; mineral)) of a silty loam under long-term wheat and maize cultivation. The isotopic signature of neutral sugars was measured by high pressure liquid chromatography coupled to isotope ratio mass spectrometry (HPLC/IRMS), after hydrolysis with 4 M Trifluoroacetic acid. While apparent MRT of sugars were comparable to total organic carbon in the bulk soil and mineral fraction, the apparent MRT of sugar carbon in the oPOM fractions were considerably lower than those of the total carbon of these fractions. This indicates that oPOM formation was fuelled by microbial activity feeding on new plant input. In the bulk soil, MRT of the mainly plant-derived xylose were significantly lower than those of mainly microbial-derived sugars like galactose, rhamnose, fucose, indicating that recycling of organic matter is an important factor regulating organic matter dynamics in

  13. Non-Starchy Vegetables

    MedlinePlus

    ... the non-starchy vegetables . Starchy vegetables like potatoes, corn and peas are included in the " Grains and ... or Chinese spinach Artichoke Artichoke hearts Asparagus Baby corn Bamboo shoots Beans (green, wax, Italian) Bean sprouts ...

  14. Fruits and vegetables (image)

    MedlinePlus

    A healthy diet includes adding vegetables and fruit every day. Vegetables like broccoli, green beans, leafy greens, zucchini, cauliflower, cabbage, carrots, and tomatoes are low in calories and high in fiber, ...

  15. Handling Procedures of Vegetable Crops

    NASA Technical Reports Server (NTRS)

    Perchonok, Michele; French, Stephen J.

    2004-01-01

    The National Aeronautics and Space Administration (NASA) is working towards future long duration manned space flights beyond low earth orbit. The duration of these missions may be as long as 2.5 years and will likely include a stay on a lunar or planetary surface. The primary goal of the Advanced Food System in these long duration exploratory missions is to provide the crew with a palatable, nutritious, and safe food system while minimizing volume, mass, and waste. Vegetable crops can provide the crew with added nutrition and variety. These crops do not require any cooking or food processing prior to consumption. The vegetable crops, unlike prepackaged foods, will provide bright colors, textures (crispy), and fresh aromas. Ten vegetable crops have been identified for possible use in long duration missions. They are lettuce, spinach, carrot, tomato, green onion, radish, bell pepper, strawberries, fresh herbs, and cabbage. Whether these crops are grown on a transit vehicle (e.g., International Space Station) or on the lunar or planetary surface, it will be necessary to determine how to safely handle the vegetables while maintaining acceptability. Since hydrogen peroxide degrades into water and oxygen and is generally recognized as safe (GRAS), hydrogen peroxide has been recommended as the sanitizer. The objective of th is research is to determine the required effective concentration of hydrogen peroxide. In addition, it will be determined whether the use of hydrogen peroxide, although a viable sanitizer, adversely affects the quality of the vegetables. Vegetables will be dipped in 1 % hydrogen peroxide, 3% hydrogen peroxide, or 5% hydrogen peroxide. Treated produce and controls will be stored in plastic bags at 5 C for up to 14 days. Sensory, color, texture, and total plate count will be measured. The effect on several vegetables including lettuce, radish, tomato and strawberries has been completed. Although each vegetable reacts to hydrogen peroxide differently, the

  16. Natural vegetation inventory

    NASA Technical Reports Server (NTRS)

    Schrumpf, B. J.

    1973-01-01

    Unique characteristics of ERTS imagery can be used to inventory natural vegetation. While satellite images can seldom be interpreted and identified directly in terms of vegetation types, such types can be inferred by interpretation of physical terrain features and through an understanding of the ecology of the vegetation.

  17. THE VEGETATIVE MERISTEM

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The vegetative shoot apical meristem is a highly organized yet dynamic structure. It is responsible for maintaining the proliferation of a population of undifferentiated stem cells through-out vegetative development, as well as for initiating lateral organs in stereotypical patterns. The vegetative...

  18. Decadal Contributions of Fire Disturbance to the Carbon Balance of Boreal Ecosystems Using a Process-Based Global Dynamic Vegetation Model

    NASA Astrophysics Data System (ADS)

    Yue, C.; Ciais, P.; Zhu, D.; Wang, T.; Peng, S.; Krinner, G.

    2014-12-01

    Fires are an intrinsic disturbance factor over the boreal regions. Fire impacts ecosystem biophysical properties and carbon stocks, and over long time scales, species composition and fires have strong interactions. The contemporary carbon sink in the Northern Hemisphere is partly related to the forest recovery from the legacy of historical fire disturbances. However very little is known on the relative contributions to the current-day carbon sink from past fires that occurred at different times in the recent history. In the present study we develop a novel conceptual approach to quantify the decadal contributions of fires during the 20th century to the carbon balance of the early 21st century, by modelling the legacy sink created by decadal cohorts of past fires. This quantification is realized by conducting a suite of simulations using the ORCHIDEE global dynamic vegetation model, in which the prognostic SPITFIRE fire module was turned off in each decade sequentially during the 20th century, and turned before and after, to account for carbon storage recovery. The vegetation dynamics interact with fires via the dynamic vegetation module of ORCHIDEE, in which fire impacts vegetation mortality and tree-grass competition. We found that the existence of fires reduces the forest coverage in the transitional forest-grassland zone around 45oN-50oN region over central Asia. In this region, the existence of recurrent fire acts to lower equilibrium biomass and soil carbon stocks. Historical fire disturbances and the resulting forest successional dynamics contribute a legacy to the boreal carbon sink during the period 2010-2011, with the lagged sink effects of fires that happened in the recent three decades accounting for over 70% of the total fire-induced sink during 2010-2011. Most of current sink from past fires is contributed by fires with moderate frequency with fire return intervals of 10-100 years.

  19. Stereophotogrammetry in studies of riparian vegetation dynamics

    NASA Astrophysics Data System (ADS)

    Hortobagyi, Borbala; Vautier, Franck; Corenblit, Dov; Steiger, Johannes

    2014-05-01

    Riparian vegetation responds to hydrogeomorphic disturbances and also controls sediment deposition and erosion. Spatio-temporal riparian vegetation dynamics within fluvial corridors have been quantified in many studies using aerial photographs and GIS. However, this approach does not allow the consideration of woody vegetation growth rates (i.e. vertical dimension) which are fundamental when studying feedbacks between the processes of fluvial landform construction and vegetation establishment and succession. We built 3D photogrammetric models of vegetation height based on aerial argentic and digital photographs from sites of the Allier and Garonne Rivers (France). The models were realized at two different spatial scales and with two different methods. The "large" scale corresponds to the reach of the river corridor on the Allier river (photograph taken in 2009) and the "small" scale to river bars of the Allier (photographs taken in 2002, 2009) and Garonne Rivers (photographs taken in 2000, 2002, 2006 and 2010). At the corridor scale, we generated vegetation height models using an automatic procedure. This method is fast but can only be used with digital photographs. At the bar scale, we constructed the models manually using a 3D visualization on the screen. This technique showed good results for digital and also argentic photographs but is very time-consuming. A diachronic study was performed in order to investigate vegetation succession by distinguishing three different classes according to the vegetation height: herbs (<1 m), shrubs (1-4 m) or trees (>4 m). Both methods, i.e. automatic and manual, were employed to study the evolution of the three vegetation classes and the recruitment of new vegetation patches. A comparison was conducted between the vegetation height given by models (automatic and manual) and the vegetation height measured in the field. The manually produced models (small scale) were of a precision of 0.5-1 m, allowing the quantification of woody

  20. Vegetable oil fuel standards

    SciTech Connect

    Pryde, E.H.

    1982-01-01

    Suggested standards for vegetable oils and ester fuels, as well as ASTM specifications for No. 2 diesel oil are given. The following physical properties were discussed: cetane number, cloud point, distillation temperatures, flash point, pour point, turbidity, viscosity, free fatty acids, iodine value, phosphorus, and wax. It was apparent that vegetable oils and their esters cannot meet ASTM specifications D975 for No. 2 diesel oil for use in the diesel engine. Vegetable oil modification or engine design modification may make it possible eventually for vegetable oils to become suitable alternative fuels. Vegetable oils must be recognized as experimental fuels until modifications have been tested thoroughly and generally accepted. 1 table. (DP)

  1. The impact of climate and environmental processes on vegetation pattern in the Czechowskie lake catchment Czechowo Region (Northern Tuchola Pinewoods) during the Younger Dryas cooling

    NASA Astrophysics Data System (ADS)

    Noryśkiewicz, Agnieszka Maria; Kramkowski, Mateusz; Słowiński, Michał; Zawiska, Izabela; Lutyńska, Monika; Błaszkiewicz, Mirosław; Brauer, Achim

    2014-05-01

    Czechowskie lake is located in the northern part of the Tuchola Pinewoods District (Northern Poland) in a young glacial landscape. At present, the majority of the area is forested or used for agricultural purposes, but among them a high amount of basins filled with biogenic sediments are present. This area is very suitable for the postglacial vegetation development investigation because of the LST ash and laminated sediments which we found in the Trzechowskie palaeolake and Czechowskie Lake (Wulf et. all 2013). The aim of the research was to reconstruct the past landscape and vegetation response to Younger Dryas cooling and we present the results of the palinological analysis done for 6 core of biogenic sediments. Our main objective was to determine whether local factors such as topography and soil cover have a significant impact on the vegetation, eutrophy and sedimentation rate at this time. In the lake Czechowskie lake catchment we have six cores that cover postglacial succession (Lake Czechowskie small basin - profile JC-12-s; Lake Czechowskiego terrace - profile TK; Lake Czechowskie vicinity - profile "Oko and Cz/80; Trzechowskie paleolake - profile T/trz; Valley between paleolake Trzechowskie and Lake Czechowskie - profile DTCZ-4). The paleoecological research carried out involved an analysis of pollen, macrofossils, Cladocera, diatom, loss-on-ignition and CaCO3 content. The results show, that the dominant plant communities during the Youngers Dryas in the region nearby Lake Czechowskie are heliophytes xeric herb vegetation with juniper (Juniperus communis) shrubs and birch (Betula) and pine (Pinus sylvestris). In the pollen diagrams there was the difference noted in the participation of the dominant pollen, the juniper pollen was always high but varied from 18 to 37%, birch average pollen share was between 17-27%. The thickness and type of the sediment accumulated in Younger Dryas in the presented profiles differs significantly. In the profiles which

  2. Data pre-processing: Stratospheric aerosol perturbing effect on the remote sensing of vegetation: Correction method for the composite NDVI after the Pinatubo eruption

    NASA Technical Reports Server (NTRS)

    Vermote, E.; Elsaleous, N.; Kaufman, Y. J.; Dutton, E.

    1994-01-01

    An operational stratospheric correction scheme used after the Mount Pinatubo (Phillipines) eruption (Jun. 1991) is presented. The stratospheric aerosol distribution is assumed to be only variable with latitude. Each 9 days the latitudinal distribution of the optical thickness is computed by inverting radiances observed in the NOAA AVHRR channel 1 (0.63 micrometers) and channel 2 (0.83 micrometers) over the Pacific Ocean. This radiance data set is used to check the validity of model used for inversion by checking consistency of the optical thickness deduced from each channel as well as optical thickness deduced from different scattering angles. Using the optical thickness profile previously computed and radiative transfer code assuming Lambertian boundary condition, each pixel of channel 1 and 2 are corrected prior to computation of NDVI (Normalized Difference Vegetation Index). Comparison between corrected, non corrected, and years prior to Pinatubo eruption (1989 to 1990) NDVI composite, shows the necessity and the accuracy of the operational correction scheme.

  3. Vegetation establishment in convectively accelerated streams

    NASA Astrophysics Data System (ADS)

    Crouzy, B.; McLelland, S. J.; Molnar, P.; Camporeale, C.; Perona, P.

    2013-12-01

    We study the conditions for vegetation establishment within river reaches with converging boundaries. Common to many such rivers worldwide is the existence of a limiting front (e.g., Figure 1a) beyond which all the riverbed vegetation is uprooted by flooding events. There are however exceptions, which leads to an interesting ecomorphodynamic problem (existence and position of the front). We use a theoretical 1-D framework based on morphodynamic equations modified in order to account for the presence of vegetation (Perona et al., submitted), and obtain the link between the position of the vegetated front and river eco-hydraulic variables under steady and unsteady conditions. We apply our framework to a number of flume experiments (unsteady flow) where Avena sativa L. (common oat) seedlings grow subject to periodic flow disturbances within a convergent flume channel (Figure 1b). We find that depending on the outcome of the competition between hydrological and biological processes there is either a limiting spatial front within the convergent section beyond which vegetation cannot survive, or vegetation colonizes the entire riverbed. The existence and the position of the front depend on the ability for vegetation to take root efficiently and withstand uprooting by the flow of the convectively accelerated stream (Crouzy et al., in press). The active role of vegetation and of unit streampower in this particular ecomorphodynamic process are then discussed in relation to the conceptual model of Gurnell and Petts (2006), and under the light of our theoretical and experimental results. REFERENCES - Crouzy, B., K. Edmaier, N. Pasquale and P. Perona (in press). Impact of floods on the statistical distribution of riverbed vegetation. Geomorphology doi:10.1016/j.geomorph.2012.09.013. - Gurnell A., Petts G. (2006). Trees as riparian engineers: The Tagliamento River, Italy. Earth Surface Processes and Landforms, 31: 1558--1574. - Perona, P., B. Crouzy, S. Mc Lelland, P. Molnar

  4. Vegetation Change Analysis User's Manual

    SciTech Connect

    D. J. Hansen; W. K. Ostler

    2002-10-01

    Approximately 70 percent of all U.S. military training lands are located in arid and semi-arid areas. Training activities in such areas frequently adversely affect vegetation, damaging plants and reducing the resilience of vegetation to recover once disturbed. Fugitive dust resulting from a loss of vegetation creates additional problems for human health, increasing accidents due to decreased visibility, and increasing maintenance costs for roads, vehicles, and equipment. Diagnostic techniques are needed to identify thresholds of sustainable military use. A cooperative effort among U.S. Department of Energy, U.S. Department of Defense, and selected university scientists was undertaken to focus on developing new techniques for monitoring and mitigating military impacts in arid lands. This manual focuses on the development of new monitoring techniques that have been implemented at Fort Irwin, California. New mitigation techniques are described in a separate companion manual. This User's Manual is designed to address diagnostic capabilities needed to distinguish between various degrees of sustainable and nonsustainable impacts due to military training and testing and habitat-disturbing activities in desert ecosystems. Techniques described here focus on the use of high-resolution imagery and the application of image-processing techniques developed primarily for medical research. A discussion is provided about the measurement of plant biomass and shrub canopy cover in arid. lands using conventional methods. Both semiquantitative methods and quantitative methods are discussed and reference to current literature is provided. A background about the use of digital imagery to measure vegetation is presented.

  5. Probabilistic Evaluation of Anthropogenic Regulations In a Vegetated River Channel Using a Vegetation Dynamics Modeling

    NASA Astrophysics Data System (ADS)

    Miyamoto, Hitoshi

    2015-04-01

    Vegetation overgrowth in fluvial floodplains, gravel beds, and sand bars has been a serious engineering problem for riparian management in Japan. From the viewpoints of flood control and ecological conservation, it would be necessary to predict the vegetation dynamics accurately for long-term duration. In this research, we have developed a stochastic model for predicting the vegetation dynamics in fluvial floodplains with emphasis on the interaction with flood impacts. The model consists of the following four components: (i) long-term stochastic behavior of flow discharge, (ii) hydrodynamics in a channel with floodplain vegetation, (iii) variation of riverbed topography, and (iv) vegetation dynamics on floodplains. In the vegetation dynamics model, the flood discharge (i) is stochastically simulated using a filtered Poisson process, one of the conventional approaches in hydrological time-series generation. The component for vegetation dynamics (iv) includes the effects of tree growth, mortality by floods, and infant tree recruitment. Vegetation condition has been observed mainly before and after floods since 2008 at a field site located between 23-24 km from the river mouth in Kako River, Japan. The Kako River has the catchment area of 1,730 km2 and the main channel length of 96 km. This site is one of the vegetation overgrowth sites in the Kako River floodplains. The predominant tree species are willows and bamboos. In the field survey, the position, trunk diameter and height of each tree as well as the riverbed materials were measured after several flood events to investigate their impacts on the floodplain vegetation community. This presentation tries to examine effects of anthropogenic river regulations, i.e., thinning and cutting-down, in the vegetated channel in Kako River by using the vegetation dynamics model. Sensitivity of both the flood water level and the vegetation status in the channel is statistically evaluated in terms of the different cutting

  6. Soil and vegetation surveillance

    SciTech Connect

    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.

  7. Fruit and Vegetables

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Consumption of fruit and vegetable products has dramatically increased by more than 30% over the last few decades in the U.S. It is also estimated that about 20% of all fruit and vegetables produced is lost each year due to spoilage. The focus of this chapter is to provide a general background on mi...

  8. POTENTIAL NATURAL VEGETATION COVERAGE

    EPA Science Inventory

    "Potential natural vegetation is defined as the vegetation that would exist today if humans were removed from the scene and if the plant succession after their removal were telescoped into a single moment. The time compression eliminates the effects of future climatic fluc...

  9. Vegetation against dune mobility.

    PubMed

    Durán, Orencio; Herrmann, Hans J

    2006-11-01

    Vegetation is the most common and most reliable stabilizer of loose soil or sand. This ancient technique is for the first time cast into a set of equations of motion describing the competition between aeolian sand transport and vegetation growth. Our set of equations is then applied to study quantitatively the transition between barchans and parabolic dunes driven by the dimensionless fixation index theta which is the ratio between the dune characteristic erosion rate and vegetation growth velocity. We find a fixation index theta(c) below which the dunes are stabilized, characterized by scaling laws. PMID:17155579

  10. Vegetable Production System (Veggie)

    NASA Technical Reports Server (NTRS)

    Levine, Howard G.; Smith, Trent M.

    2016-01-01

    The Vegetable Production System (Veggie) was developed by Orbital Technologies Corp. to be a simple, easily stowed, and high growth volume yet low resource facility capable of producing fresh vegetables on the International Space Station (ISS). In addition to growing vegetables in space, Veggie can support a variety of experiments designed to determine how plants respond to microgravity, provide real-time psychological benefits for the crew, and conduct outreach activities. Currently, Veggie provides the largest volume available for plant growth on the ISS.

  11. The role of historical barriers in the diversification processes in open vegetation formations during the Miocene/Pliocene using an ancient rodent lineage as a model.

    PubMed

    Nascimento, Fabrícia F; Lazar, Ana; Menezes, Albert N; Durans, Andressa da Matta; Moreira, Jânio C; Salazar-Bravo, Jorge; D'Andrea, Paulo S; Bonvicino, Cibele R

    2013-01-01

    The Neotropics harbors a high diversity of species and several hypotheses have been proposed to account for this pattern. However, while species of forested domains are frequently studied, less is known of species from open vegetation formations occupying, altogether, a larger area than the Amazon Forest. Here we evaluate the role of historical barriers and the riverine hypothesis in the speciation patterns of small mammals by analyzing an ancient rodent lineage (Thrichomys, Hystricomorpha). Phylogenetic and biogeographic analyses were carried out with mitochondrial and nuclear DNA markers to analyze the evolutionary relationships between Thrichomys lineages occurring in dry domains along both banks of the Rio São Francisco. This river is one of the longest of South America whose course and water flow have been modified by inland tectonic activities and climate changes. Molecular data showed a higher number of lineages than previously described. The T. inermis species complex with 2n = 26, FN = 48 was observed in both banks of the river showing a paraphyletic arrangement, suggesting that river crossing had occurred, from east to west. A similar pattern was also observed for the T. apereoides complex. Thrichomys speciation occurred in Late Miocene when the river followed a different course. The current geographic distribution of Thrichomys species and their phylogenetic relationships suggested the existence of frequent past connections between both banks in the middle section of the Rio São Francisco. The extensive palaeodune region found in this area has been identified as a centre of endemism of several vertebrate species and is likely to be a center of Thrichomys diversification. PMID:24349576

  12. The Role of Historical Barriers in the Diversification Processes in Open Vegetation Formations during the Miocene/Pliocene Using an Ancient Rodent Lineage as a Model

    PubMed Central

    Nascimento, Fabrícia F.; Lazar, Ana; Menezes, Albert N.; Durans, Andressa da Matta; Moreira, Jânio C.; Salazar-Bravo, Jorge; D′Andrea, Paulo S.; Bonvicino, Cibele R.

    2013-01-01

    The Neotropics harbors a high diversity of species and several hypotheses have been proposed to account for this pattern. However, while species of forested domains are frequently studied, less is known of species from open vegetation formations occupying, altogether, a larger area than the Amazon Forest. Here we evaluate the role of historical barriers and the riverine hypothesis in the speciation patterns of small mammals by analyzing an ancient rodent lineage (Thrichomys, Hystricomorpha). Phylogenetic and biogeographic analyses were carried out with mitochondrial and nuclear DNA markers to analyze the evolutionary relationships between Thrichomys lineages occurring in dry domains along both banks of the Rio São Francisco. This river is one of the longest of South America whose course and water flow have been modified by inland tectonic activities and climate changes. Molecular data showed a higher number of lineages than previously described. The T. inermis species complex with 2n = 26, FN = 48 was observed in both banks of the river showing a paraphyletic arrangement, suggesting that river crossing had occurred, from east to west. A similar pattern was also observed for the T. apereoides complex. Thrichomys speciation occurred in Late Miocene when the river followed a different course. The current geographic distribution of Thrichomys species and their phylogenetic relationships suggested the existence of frequent past connections between both banks in the middle section of the Rio São Francisco. The extensive palaeodune region found in this area has been identified as a centre of endemism of several vertebrate species and is likely to be a center of Thrichomys diversification. PMID:24349576

  13. Impact of natural climate change and historical land use on vegetation cover and geomorphological process dynamics in the Serra dos Órgãos mountain range in Rio de Janeiro State, Brazil

    NASA Astrophysics Data System (ADS)

    Nehren, U.; Sattler, D.; Heinrich, J.

    2010-03-01

    The Serra dos Órgãos mountain range in the hinterland of Rio de Janeiro contains extensive remnants of the Atlantic Forest (Mata Atlântica) biome, which once covered about 1.5 million km² from Northeast to South Brazil and further inland to Paraguay and Argentina. As a result of historical deforestation and recent land use intensification processes today only 5 to 8% of the original Atlantic Forest remains. Despite the dramatic habitat loss and a high degree of forest fragmentation, the remnants are among the Earth’s most diverse habitats in terms of species richness. Furthermore, they are characterized by a high level of endemism. Therefore, the biome is considered a "hotspot of biodiversity". In the last years many efforts have been taken to investigate the Mata Atlântica biome in different spatial and time scales and from different scientific perspectives. We are working in the Atlantic Forest of Rio de Janeiro since 2004 and focus in our research particularly on Quaternary landscape evolution and landscape history. By means of landscape and soil archives we reconstruct changes in the landscape system, which are mainly the result of Quaternary climate variability, young tectonic uplift and human impact. The findings throw light on paleoecological conditions in the Late Quaternary and the impact of pre-colonial and colonial land use practices on these landscapes. In this context, a main focus is set on climate and human-driven changes of the vegetation cover and its consequences for the geomorphological process dynamics, in particular erosion and sedimentation processes. Research methods include geomorphological field studies, interpretation of satellite images, physical and chemical sediment and soil analyses as well as relative and absolute dating (Feo/Fed ratio and 14C dating). For the Late Quaternary landscape evolution, the findings are compared with results from paleoclimatic and paloecological investigations in Southeast and South Brazil using other

  14. Scaling Vegetation on Experimental Channel Patterns

    NASA Astrophysics Data System (ADS)

    van Breemen, D. M.; van de Lageweg, W. I.; van Dijk, W. M.; Kleinhans, M. G.

    2010-12-01

    There are strong feedbacks between river channels, floodplains and riparian and floodplain vegetation. We study the effect of experimental vegetation on channel pattern. Through linear bar theory it is known that channel width-depth ratio affects bar pattern and relatively narrow channels with strong banks are required for meandering. Riparian vegetation is able to alter the channel width-depth ratio and therefore the channel pattern through strengthening of the banks. Floodplain vegetation adds hydraulic resistance so the flow is more focused into the channels. However, determination of the underlying mechanisms and processes has remained scarce and qualitative and hence these effects are not yet fully understood. The objectives of this study are 1) to develop a controllable and scalable method to reproduce vegetation effect in experimental self-formed channels, and 2) to experimentally determine the effects of riparian vegetation on bank strength, channel pattern and meandering dynamics. Sprouts of three plant species were systematically subjected to different seeding densities and to various growing conditions, including light intensity, submergence and nutrient starvation. Denser seeding reduced sprout growth after about a week. Stronger light increased plant growth and plant strength. Nutrient starvation caused different branching intensity of the root system. Tens of small-scale bank erosion experiments and bank failure experiments (see Kleinhans et al., this conference) were performed to quantify the strength of banks reinforced by plant roots at the experimental scale, demonstrating that bank strength is strongly determined by seeding density, rooting density and depth relative to channel depth. To study pattern evolution and morphodynamics we used a 1.25x7.5 m flume with a constant discharge and sediment feed. The introduction of vegetation in experiments results in narrower and deeper channels. Higher vegetation density leads to static channels with

  15. Vegetable oil fuels

    SciTech Connect

    Not Available

    1982-01-01

    Fifty contributions (presentations) involving more than one hundred people worldwide were given at the International Conference on Plant and Vegetable Oils as Fuels. The proceedings were in Fargo, North Dakota, from August 2-4, 1982. The conference helped to promote renewable fuels, bio-oils, from plant and vegetable oils. Separate abstracts were prepared for 44 items for inclusion in the Energy Data Base.

  16. Monitoring global vegetation

    NASA Technical Reports Server (NTRS)

    Macdonald, R. B.; Houston, A. G.; Heydorn, R. P.; Botkin, D. B.; Estes, J. E.; Strahler, A. H.

    1981-01-01

    An attempt is made to identify the need for, and the current capability of, a technology which could aid in monitoring the Earth's vegetation resource on a global scale. Vegetation is one of our most critical natural resources, and accurate timely information on its current status and temporal dynamics is essential to understand many basic and applied environmental interrelationships which exist on the small but complex planet Earth.

  17. Family members' influence on family meal vegetable choices

    PubMed Central

    Wenrich, Tionni R.; Brown, J. Lynne; Miller-Day, Michelle; Kelley, Kevin J.; Lengerich, Eugene J.

    2010-01-01

    Objective Characterize the process of family vegetable selection (especially cruciferous, deep orange, and dark green leafy vegetables); demonstrate the usefulness of Exchange Theory (how family norms and past experiences interact with rewards and costs) for interpreting the data. Design Eight focus groups, two with each segment (men/women vegetable-likers/dislikers based on a screening form). Participants completed a vegetable intake form. Setting Rural Appalachian Pennsylvania. Participants 61 low-income, married/cohabiting men (n=28) and women (n=33). Analysis Thematic analysis within Exchange Theory framework for qualitative data. Descriptive analysis, t-tests and chi-square tests for quantitative data. Results Exchange Theory proved useful for understanding that regardless of sex or vegetable-liker/disliker status, meal preparers see more costs than rewards to serving vegetables. Past experience plus expectations of food preparer role and of deference to family member preferences supported a family norm of serving only vegetables acceptable to everyone. Emphasized vegetables are largely ignored due to unfamiliarity; family norms prevented experimentation and learning through exposure. Conclusions and Implications Interventions to increase vegetable consumption of this audience could 1) alter family norms about vegetables served, 2) change perceptions of past experiences, 3) reduce social and personal costs of serving vegetables and 4) increase tangible and social rewards of serving vegetables. PMID:20452288

  18. Post-fire vegetation recovery in Portugal based on spot/vegetation data

    NASA Astrophysics Data System (ADS)

    Gouveia, C.; Dacamara, C. C.; Trigo, R. M.

    2010-04-01

    A procedure is presented that allows identifying large burned scars and the monitoring of vegetation recovery in the years following major fire episodes. The procedure relies on 10-day fields of Maximum Value Composites of Normalized Difference Vegetation Index (MVC-NDVI), with a 1 km×1 km spatial resolution obtained from the VEGETATION instrument. The identification of fire scars during the extremely severe 2003 fire season is performed based on cluster analysis of NDVI anomalies that persist during the vegetative cycle of the year following the fire event. Two regions containing very large burned scars were selected, located in Central and Southwestern Portugal, respectively, and time series of MVC-NDVI analysed before the fire events took place and throughout the post-fire period. It is shown that post-fire vegetation dynamics in the two selected regions may be characterised based on maps of recovery rates as estimated by fitting a monoparametric model of vegetation recovery to MVC-NDVI data over each burned scar. Results indicated that the recovery process in the region located in Central Portugal is mostly related to fire damage rather than to vegetation density before 2003, whereas the latter seems to have a more prominent role than vegetation conditions after the fire episode, e.g. in the case of the region in Southwestern Portugal. These differences are consistent with the respective predominant types of vegetation. The burned area located in Central Portugal is dominated by Pinus Pinaster whose natural regeneration crucially depends on the destruction of seeds present on the soil surface during the fire, whereas the burned scar in Southwestern Portugal was populated by Eucalyptus that may quickly re-sprout from buds after fire. Besides its simplicity, the monoparametric model of vegetation recovery has the advantage of being easily adapted to other low-resolution satellite data, as well as to other types of vegetation indices.

  19. Biomechanics of fruits and vegetables.

    PubMed

    Peleg, K

    1985-01-01

    The scope of fruit and vegetable biomechanics is reviewed. Sources of mechanical injury to produce in harvesting, processing, storage, packaging and transportation are briefly described. A survey of produce handling and transportation environments was conducted, whereby an envelope model encompassing composite spectra of trucks, railroad, marine and cargo aircraft is presented. The protective quality, i.e. strength of shipping containers is quantified in static and dynamic loading such as encountered in storage, handling and transportation. Mechanical response of fruits and vegetables in quasistatic and dynamic loading are formulated by a nonlinear rheological model, whereby a time and deformation dependent relaxation modulus is defined. A realistic link is established between the model and real fruits and vegetables by test procedures for determination of the parameters in the governing nonlinear equations. Based on the nonlinear relaxation modulus, mechanical damage of fruits and vegetables is quantified for static compression, transients and vibration loading as well as for combined static and dynamic loading, by equations of contact circle diameter, bruise depth and contact pressure. Distribution of loads over a maximal number of contact points per fruit is linked to geometrical patterns of produce packs. The application of Shock Damage Boundary techniques for produce-package testing is described along with a case study comparing the protective qualities of two types of apple packs. Produce damage quantification by direct fruit inspection in terms of a 'Bruise Index' is described, including a practical example, comparing the protective qualities of three types of apple packs in shipping tests. Indirect methods of mechanical injury evaluation, based on weight loss and CO2 emission differences between bruised and wholesome fruits are also briefly discussed. PMID:4077855

  20. Use of response surface methodology to study the combined effects of UV-C and thermal process on vegetable oxidative enzymes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of ultraviolet processing (UV-C) (temperature, exposure time, and wavelength) and an environmental parameter (pH) were studied on three oxidative enzymes, namely, lipoxygenase (LOX), peroxidase (POD) and polyphenoloxidase (PPO) by using a central composite design. An initial screening de...

  1. Products from vegetable oils

    SciTech Connect

    Bagby, M.O.

    1995-12-01

    Vegetable oils serve various industrial applications such as plasticizers, emulsifiers, surfactants, plastics and resins. Research and development approaches may take advantage of natural properties of the oils. More often it is advantageous to modify those properties for specific applications. One example is the preparation of ink vehicles using vegetable oils in the absence of petroleum. They are cost competitive with petroleum-based inks with similar quality factors. Vegetable oils have potential as renewable sources of fuels for the diesel engine. However, several characteristics can restrict their use. These include poor cold-engine startup, misfire and for selected fuels, high pour point and cloud point temperatures. Other characteristics include incomplete combustion causing carbon buildup, lube oil dilution and degradation, and elevated NO{sub x} emissions. Precombustion and fuel quality data are presented as a tool for understanding and solving these operational and durability problems.

  2. On the evaluation of vegetation resilience in Southern Italy by using satellite VEGETATION, MODIS, TM time series

    NASA Astrophysics Data System (ADS)

    Coluzzi, C.; Didonna, I.

    2009-04-01

    Satellite technologies can be profitably used for investigating the dynamics of vegetation re-growth after disturbance at different temporal and spatial scales. Nevertheless, disturbance -induced dynamical processes are very difficult to study since they affect the complex soil-surface-atmosphere system, due to the existence of feedback mechanisms involving human activity, ecological patterns and different subsystems of climate. The remote sensing of vegetation has been traditionally carried out by using vegetation indices, which are quantitative measures, based on vegetation spectral properties, that attempt to measure biomass or vegetative vigor. The vegetation indices operate by contrasting intense chlorophyll pigment absorption in the red against the high reflectance of leaf mesophyll in the near infrared. The simplest form of vegetation index is simply a ratio between two digital values from these two spectral bands. The most widely used index is the well-known normalized difference vegetation index NDVI = [NIR-R]/ [NIR+R]. The normalization of the NDVI reduces the effects of variations caused by atmospheric contaminations. High values of the vegetation index identify pixels covered by substantial proportions of healthy vegetation. NDVI is indicative of plant photosynthetic activity and has been found to be related to the green leaf area index and the fraction of photosynthetically active radiation absorbed by vegetation. Therefore variations in NDVI values become indicative of variations in vegetation composition and dynamics. In this study, we analyze the mutiscale satellite temporal series ( 1998 to 2008) of NDVI and other vegetation indices from SPOT VEGETATION and Landsat TM data acquired for some significant test areas affetced and unaffected (Southern Italy) by different type of environmenta diturbances (drought, salinity, pollution, etc). Our objective is to characterize quantitatively the resilient effect of vegetation cover at different temporal and

  3. On the evaluation of vegetation resilience in Southern Italy by using VEGETATION, MODIS, TM satellite time series

    NASA Astrophysics Data System (ADS)

    Didonna, I.; Coluzzi, R.

    2009-04-01

    Satellite technologies can be profitably used for investigating the dynamics of vegetation re-growth after disturbance at different temporal and spatial scales. Nevertheless, disturbance -induced dynamical processes are very difficult to study since they affect the complex soil-surface-atmosphere system, due to the existence of feedback mechanisms involving human activity, ecological patterns and different subsystems of climate. The remote sensing of vegetation has been traditionally carried out by using vegetation indices, which are quantitative measures, based on vegetation spectral properties, that attempt to measure biomass or vegetative vigor. The vegetation indices operate by contrasting intense chlorophyll pigment absorption in the red against the high reflectance of leaf mesophyll in the near infrared. The simplest form of vegetation index is simply a ratio between two digital values from these two spectral bands. The most widely used index is the well-known normalized difference vegetation index NDVI = [NIR-R]/ [NIR+R]. The normalization of the NDVI reduces the effects of variations caused by atmospheric contaminations. High values of the vegetation index identify pixels covered by substantial proportions of healthy vegetation. NDVI is indicative of plant photosynthetic activity and has been found to be related to the green leaf area index and the fraction of photosynthetically active radiation absorbed by vegetation. Variations in NDVI values become indicative of variations in vegetation composition and dynamics. In this study, we analyze the mutiscale satellite temporal series ( 2000 to 2008) of NDVI and other vegetation indices from SPOT VEGETATION, MODIS and Landsat TM data acquired for some significant test areas affetced and unaffected (Southern Italy) by different types of environmental diturbances (drought, salinity, pollution, etc). Our objective was to characterize quantitatively the resilient effect of vegetation cover at differen temporal and

  4. Straight Vegetable Oil as a Diesel Fuel?

    SciTech Connect

    2014-01-01

    Biodiesel, a renewable fuel produced from animal fats or vegetable oils, is popular among many vehicle owners and fleet managers seeking to reduce emissions and support U.S. energy security. Questions sometimes arise about the viability of fueling vehicles with straight vegetable oil (SVO), or waste oils from cooking and other processes, without intermediate processing. But SVO and waste oils differ from biodiesel (and conventional diesel) in some important ways and are generally not considered acceptable vehicle fuels for large-scale or long-term use.

  5. Temporal trends in earth-atmosphere system reflectance factor for sagebrush steppe vegetation communities

    NASA Technical Reports Server (NTRS)

    Strong, Laurence L.

    1987-01-01

    Four consecutive Landsat-5 Thematic Mapper acquisitions were used to examine trends in earth-atmosphere system reflectance factors of sagebrush steppe vegetation communities following soil moisture recharge from snow melt. Significant differences in trends between vegetation communities correspond to known differences in the initiation and duration of active vegetation growth. Information on short-term vegetation processes are a valuable supplement to estimates of total vegetation cover which can be obtained using satellite brightness images at less frequent temporal intervals.

  6. Systems study of vegetable oils and animal fats for use as substitute and emergency diesel fuels

    SciTech Connect

    Lipinsky, E.S.; McClure, T.A.; Kresovich, S.; Otis, J.L.; Wagner, C.K.; Trayser, D.A.; Applebaum, H.R.

    1981-10-01

    The principal findings are described as follows: leading issues, economic considerations, production potential for oilseed crops, oilseed processing, energy balance, diesel fuel and engine considerations, vegetable oil emissions, and research and development needs. The following appendices are included: profiles of selected vegetable oils and animal fats, economic information on vegetable oils and animal fats, the production potential for selected oilseed crops, the economics of vegetable oil recovery, and diesel fuel specifications and vegetable oil properties.

  7. Modeling aeolian erosion in presence of vegetation

    NASA Astrophysics Data System (ADS)

    Dupont, S.; Bergametti, G.; Simoëns, S.

    2014-02-01

    Semiarid landscapes are characterized by vegetated surfaces. Understanding the impact of vegetation on aeolian soil erosion is important for reducing soil erosion or limiting crop damage through abrasion or burial. In the present study, a saltation model fully coupled with a large-eddy simulation airflow model is extended to vegetated landscapes. From this model, the sensitivity of sand erosion to different arrangements and type of plants (shrub versus tree) representative of semiarid landscapes is investigated and the wind erosion reduction induced by plants is quantified. We show that saltation processes over vegetated surfaces have a limited impact on the mean wind statistics, the momentum extracted from the flow by saltating particles being negligible compared to that extracted by plants. Simulated sand erosion patterns resulting from plant distribution, i.e., accumulation and erosion areas, appear qualitatively consistent with previous observations. It is shown that sand erosion reduction depends not only on vegetation cover but also on plant morphology and plant distribution relative to the mean wind direction. A simple shear stress partitioning approach applied in shrub cases gives similar trends of sand erosion reduction as the present model following wind direction and vegetation cover. However, the magnitude of the reduction appears significantly different from one approach to another. Although shrubs trap saltating particles, trees appear more efficient than shrubs to reduce sand erosion. This is explained by the large-scale sheltering effect of trees compared to the local shrub one.

  8. Climate Change Implications to Vegetation Production in Alaska

    NASA Technical Reports Server (NTRS)

    Neigh, Christopher S.R.

    2008-01-01

    Investigation of long-term meteorological satellite data revealed statistically significant vegetation response to climate drivers of temperature, precipitation and solar radiation with exclusion of fire disturbance in Alaska. Abiotic trends were correlated to satellite remote sensing observations of normalized difference vegetation index to understand biophysical processes that could impact ecosystem carbon storage. Warming resulted in disparate trajectories for vegetation growth due to precipitation and photosynthetically active radiation variation. Interior spruce forest low lands in late summer through winter had precipitation deficit which resulted in extensive fire disturbance and browning of undisturbed vegetation with reduced post-fire recovery while Northern slope moist alpine tundra had increased production due to warmer-wetter conditions during the late 1990s and early 2000s. Coupled investigation of Alaska s vegetation response to warming climate found spatially dynamic abiotic processes with vegetation browning not a result from increased fire disturbance.

  9. Linking Weathering, Rock Moisture Dynamics, Geochemistry, Runoff, Vegetation and Atmospheric Processes through the Critical Zone: Graduate Student led Research at the Eel River Critical Zone Observatory

    NASA Astrophysics Data System (ADS)

    Dietrich, W. E.

    2014-12-01

    In the Eel River Critical Zone Observatory lies Rivendell, a heavily-instrumented steep forested hillslope underlain by nearly vertically dipping argillite interbedded with sandstone. Under this convex hillslope lies "Zb", the transition to fresh bedrock, which varies from less than 6 m below the surface near the channel to 20 m at the divide. Rempe and Dietrich (2014, PNAS) show that the Zb profile can be predicted from the assumption that weathering occurs when drainage is induced in the uplifting fresh bedrock under hillslopes by lateral head gradients driven by channel incision at the hillslope boundary. Infiltrating winter precipitation is impeded at the lower conductivity boundary at Zb, generating perched groundwater that dynamically pulses water laterally to the channel, controlling stream runoff. Below the soil and above the water table lies an unsaturated zone through which all recharge to the perched groundwater (and thus all runoff to channels) occurs. It is this zone and the waters in them that profoundly affect critical zone processes. In our seasonally dry environment, the first rains penetrate past the soil and moisten the underlying weathered bedrock (Salve et al., 2012, WRR). It takes about 200 to 400 mm of cumulative rain, however, before the underlying groundwater rises significantly. Oshun et al (in review) show that by this cumulative rainfall the average of the wide-ranging isotopic signature of rain reaches a nearly constant average annual value. Consequently, the recharging perched groundwater shows only minor temporal isotopic variation. Kim et al, (2014, GCA) find that the winter high-flow groundwater chemistry is controlled by relatively fast-reacting cation exchange processes, likely occurring in transit in the unsaturated zone. Oshun also demonstrates that the Douglas fir rely on this rock moisture as a water source, while the broadleaf trees (oaks and madrone) use mostly soil moisture. Link et al (2014 WRR) show that Doug fir declines

  10. Effects of climate and lifeform on dry matter yield (epsilon) from simulations using BIOME BGC. [ecosystem process model for vegetation biomass production using daily absorbed photosynthetically active radiation

    NASA Technical Reports Server (NTRS)

    Hunt, E. R., Jr.; Running, Steven W.

    1992-01-01

    An ecosystem process simulation model, BIOME-BGC, is used in a sensitivity analysis to determine the factors that may cause the dry matter yield (epsilon) and annual net primary production to vary for different ecosystems. At continental scales, epsilon is strongly correlated with annual precipitation. At a single location, year-to-year variation in net primary production (NPP) and epsilon is correlated with either annual precipitation or minimum air temperatures. Simulations indicate that forests have lower epsilon than grasslands. The most sensitive parameter affecting forest epsilon is the total amount of living woody biomass, which affects NPP by increasing carbon loss by maintenance respiration. A global map of woody biomass should significantly improve estimates of global NPP using remote sensing.

  11. Evaluating models of climate and forest vegetation

    NASA Technical Reports Server (NTRS)

    Clark, James S.

    1992-01-01

    Understanding how the biosphere may respond to increasing trace gas concentrations in the atmosphere requires models that contain vegetation responses to regional climate. Most of the processes ecologists study in forests, including trophic interactions, nutrient cycling, and disturbance regimes, and vital components of the world economy, such as forest products and agriculture, will be influenced in potentially unexpected ways by changing climate. These vegetation changes affect climate in the following ways: changing C, N, and S pools; trace gases; albedo; and water balance. The complexity of the indirect interactions among variables that depend on climate, together with the range of different space/time scales that best describe these processes, make the problems of modeling and prediction enormously difficult. These problems of predicting vegetation response to climate warming and potential ways of testing model predictions are the subjects of this chapter.

  12. Fermented and Acidified Vegetables

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vegetables may be preserved by fermentation, direct acidification, or a combination of these along with pasteurization or refrigeration and selected additives to yield products with an extended shelf life and enhanced safety. Organic acids such as lactic, acetic, sorbic and benzoic acids along with ...

  13. Vegetable Soup Activities.

    ERIC Educational Resources Information Center

    Shepard, Mary; Shepard, Ray

    Vegetable Soup is a new children's television series whose purpose is to counter the negative and destructive effects of racial isolation. This manual gives detailed instructions for discussion of activities that are presented during the television series such as: crafts, games, recipes, language activities, and children's questions. A list of…

  14. Vegetable oil as fuel

    SciTech Connect

    Not Available

    1980-11-01

    A review is presented of various experiments undertaken over the past few years in the U.S. to test the performance of vegetable oils in diesel engines, mainly with a view to on-farm energy self-sufficiency. The USDA Northern Regional Research Center in Peoria, Illinois, is screening native U.S. plant species as potential fuel oil sources.

  15. Estimating the vegetation water content using a radar vegetation index

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vegetation water content is an important biophysical parameter. Here, the Radar Vegetation Index (RVI) based on polarimetric backscatter observations was evaluated for estimating vegetation water content. Analysis utilized a data set obtained by a ground-based multi-frequency polarimetric scatterome...

  16. Cruciferous Vegetables and Cancer Prevention

    MedlinePlus

    ... vegetables are part of the Brassica genus of plants. They include the following vegetables, among others: Arugula ... Jain MG, Hislop GT, Howe GR, Ghadirian P. Plant foods, antioxidants, and prostate cancer risk: findings from ...

  17. Refinement of microwave vegetation indices

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous investigations have established the basis for a new type of vegetation index based on passive microwave satellite observations. These microwave vegetation indices (MVIs) have been qualitatively evaluated by examining global spatial and seasonal temporal features. Limited quantitative studie...

  18. Vegetable oil based grease formulations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Environmental concerns have brought forward vegetable oils as alternatives to more expensive synthetic lubricant base oils and less environmental friendly petroleum base stocks, in moderate operating conditions. Vegetable oils are becoming an obvious choice for potential replacement of petroleum ba...

  19. FLUVIAL DISTURBANCE AND WETLAND VEGETATION DEVELOPMENT, UPPER MAIN STEM, WILLAMETTE RIVER, OREGON, USA

    EPA Science Inventory

    Hydrogeomorphic processes drive vegetation establishment, and promote development of diverse wetland and riparian types associated with lotic ecosystems. The main objective of this study was to estimate the rate and pattern of vegetation development on bars tracked since 1936, a...

  20. Toward a comprehensive landscape vegetation monitoring framework

    NASA Astrophysics Data System (ADS)

    Kennedy, Robert; Hughes, Joseph; Neeti, Neeti; Larrue, Tara; Gregory, Matthew; Roberts, Heather; Ohmann, Janet; Kane, Van; Kane, Jonathan; Hooper, Sam; Nelson, Peder; Cohen, Warren; Yang, Zhiqiang

    2016-04-01

    Blossoming Earth observation resources provide great opportunity to better understand land vegetation dynamics, but also require new techniques and frameworks to exploit their potential. Here, I describe several parallel projects that leverage time-series Landsat imagery to describe vegetation dynamics at regional and continental scales. At the core of these projects are the LandTrendr algorithms, which distill time-series earth observation data into periods of consistent long or short-duration dynamics. In one approach, we built an integrated, empirical framework to blend these algorithmically-processed time-series data with field data and lidar data to ascribe yearly change in forest biomass across the US states of Washington, Oregon, and California. In a separate project, we expanded from forest-only monitoring to full landscape land cover monitoring over the same regional scale, including both categorical class labels and continuous-field estimates. In these and other projects, we apply machine-learning approaches to ascribe all changes in vegetation to driving processes such as harvest, fire, urbanization, etc., allowing full description of both disturbance and recovery processes and drivers. Finally, we are moving toward extension of these same techniques to continental and eventually global scales using Google Earth Engine. Taken together, these approaches provide one framework for describing and understanding processes of change in vegetation communities at broad scales.

  1. A Coupled Vegetation-Crust Model for Patchy Landscapes

    NASA Astrophysics Data System (ADS)

    Kinast, Shai; Ashkenazy, Yosef; Meron, Ehud

    2016-03-01

    A new model for patchy landscapes in drylands is introduced. The model captures the dynamics of biogenic soil crusts and their mutual interactions with vegetation growth. The model is used to identify spatially uniform and spatially periodic solutions that represent different vegetation-crust states, and map them along the rainfall gradient. The results are consistent extensions of the vegetation states found in earlier models. A significant difference between the current and earlier models of patchy landscapes is found in the bistability range of vegetated and unvegetated states; the incorporation of crust dynamics shifts the onset of vegetation patterns to a higher precipitation value and increases the biomass amplitude. These results can shed new light on the involvement of biogenic crusts in desertification processes that involve vegetation loss.

  2. Family Members' Influence on Family Meal Vegetable Choices

    ERIC Educational Resources Information Center

    Wenrich, Tionni R.; Brown, J. Lynne; Miller-Day, Michelle; Kelley, Kevin J.; Lengerich, Eugene J.

    2010-01-01

    Objective: Characterize the process of family vegetable selection (especially cruciferous, deep orange, and dark green leafy vegetables); demonstrate the usefulness of Exchange Theory (how family norms and experiences interact with rewards and costs) for interpreting the data. Design: Eight focus groups, 2 with each segment (men/women vegetable…

  3. Evapotranspiration estimation in heterogeneous urban vegetation

    NASA Astrophysics Data System (ADS)

    Nagler, P. L.; Nouri, H.; Beecham, S.; Anderson, S.; Sutton, P.; Chavoshi, S.

    2015-12-01

    Finding a valid approach to measure the water requirements of mixed urban vegetation is a challenge. Evapotranspiration (ET) is the main component of a plant's water requirement. A better understanding of the ET of urban vegetation is essential for sustainable urbanisation. Increased implementation of green infrastructure will be informed by this work. Despite promising technologies and sophisticated facilities, ET estimation of urban vegetation remains insufficiently characterized. We reviewed the common field, laboratory and modelling techniques for ET estimation, mostly agriculture and forestry applications. We opted for 3 approaches of ET estimation: 1) an observational-based method using adjustment factors applied to reference ET, 2) a field-based method of Soil Water Balance (SWB) and 3) a Remote Sensing (RS)-based method. These approaches were applied to an experimental site to evaluate the most suitable ET estimation approach for an urban parkland. To determine in-situ ET, 2 lysimeters and 4 Neutron Moisture Meter probes were installed. Based on SWB principles, all input water (irrigation, precipitation and upward groundwater movements) and output water (ET, drainage, soil moisture and runoff) were measured monthly for 14 months. The observation based approach and the ground-based approach (SWB) were compared. Our predictions were compared to the actual irrigation rates (data provided by the City Council). Results suggest the observational-based method is the most appropriate urban ET estimation. We examined the capability of RS to estimate ET for urban vegetation. Image processing of 5 WorldView2 satellite images enabled modelling of the relationship between urban vegetation and vegetation indices derived from high resolution images. Our results indicate that an ETobservational-based -NDVI modelling approach is a reliable method of ET estimation for mixed urban vegetation. It also has the advantage of not depending on extensive field data collection.

  4. Vegetable oil fuels: A review

    SciTech Connect

    Karaosmanoglu, F.

    1999-04-01

    Using vegetable oils as fuel alternatives has economic, environmental, and energy benefits for Turkey. The present work provides insight to the status of vegetable oil fuels in Turkey. A brief historical background of the issue, as well as an up to date review of the research carried out on vegetable oil fuels, is given and the future of their production and application is discussed.

  5. Stochastic Evaluation of Riparian Vegetation Dynamics in River Channels

    NASA Astrophysics Data System (ADS)

    Miyamoto, H.; Kimura, R.; Toshimori, N.

    2013-12-01

    Vegetation overgrowth in sand bars and floodplains has been a serious problem for river management in Japan. From the viewpoints of flood control and ecological conservation, it would be necessary to accurately predict the vegetation dynamics for a long period of time. In this study, we have developed a stochastic model for predicting the dynamics of trees in floodplains with emphasis on the interaction with flood impacts. The model consists of the following four processes in coupling ecohydrology with biogeomorphology: (i) stochastic behavior of flow discharge, (ii) hydrodynamics in a channel with vegetation, (iii) variation of riverbed topography and (iv) vegetation dynamics on the floodplain. In the model, the flood discharge is stochastically simulated using a Poisson process, one of the conventional approaches in hydrological time-series generation. The model for vegetation dynamics includes the effects of tree growth, mortality by flood impacts, and infant tree invasion. To determine the model parameters, vegetation conditions have been observed mainly before and after flood impacts since 2008 at a field site located between 23.2-24.0 km from the river mouth in Kako River, Japan. This site is one of the vegetation overgrowth locations in Kako River floodplains, where the predominant tree species are willows and bamboos. In this presentation, sensitivity of the vegetation overgrowth tendency is investigated in Kako River channels. Through the Monte Carlo simulation for several cross sections in Kako River, responses of the vegetated channels are stochastically evaluated in terms of the changes of discharge magnitude and channel geomorphology. The expectation and standard deviation of vegetation areal ratio are compared in the different channel cross sections for different river discharges and relative floodplain heights. The result shows that the vegetation status changes sensitively in the channels with larger discharge and insensitive in the lower floodplain

  6. Fruit and vegetable allergy.

    PubMed

    Fernández-Rivas, Montserrat

    2015-01-01

    Fruit and vegetable allergies are the most prevalent food allergies in adolescents and adults. The identification of the allergens involved and the elucidation of their intrinsic properties and cross-reactivity patterns has helped in the understanding of the mechanisms of sensitisation and how the allergen profiles determine the different phenotypes. The most frequent yet contrasting fruit and vegetable allergies are pollen-food syndrome (PFS) and lipid transfer protein (LTP) syndrome. In PFS, fruit and vegetable allergies result from a primary sensitisation to labile pollen allergens, such as Bet v 1 or profilin, and the resulting phenotype is mainly mild, consisting of local oropharyngeal reactions. In contrast, LTP syndrome results from a primary sensitisation to LTPs, which are stable plant food allergens, inducing frequent systemic reactions and even anaphylaxis. Although much less prevalent, severe fruit allergies may be associated with latex (latex-fruit syndrome). Molecular diagnosis is essential in guiding the management and risk assessment of these patients. Current management strategies comprise avoidance and rescue medication, including adrenaline, for severe LTP allergies. Specific immunotherapy with pollen is not indicated to treat pollen-food syndrome, but sublingual immunotherapy with LTPs seems to be a promising therapy for LTP syndrome. PMID:26022876

  7. Organochlorine (chlordecone) uptake by root vegetables.

    PubMed

    Florence, Clostre; Philippe, Letourmy; Magalie, Lesueur-Jannoyer

    2015-01-01

    Chlordecone, an organochlorine insecticide, continues to pollute soils in the French West Indies. The main source of human exposure to this pollutant is food. Root vegetables, which are staple foods in tropical regions, can be highly contaminated and are thus a very effective lever for action to reduce consumer exposure. We analyzed chlordecone contamination in three root vegetables, yam, dasheen and sweet potato, which are among the main sources of chlordecone exposure in food in the French West Indies. All soil types do not have the same potential for the contamination of root vegetables, allophanic andosols being two to ten times less contaminating than non-allophanic nitisols and ferralsols. This difference was only partially explained by the higher OC content in allophanic soils. Dasheen corms were shown to accumulate more chlordecone than yam and sweet potato tubers. The physiological nature of the root vegetable may explain this difference. Our results are in good agreement with the hypothesis that chlordecone uptake by root vegetables is based on passive and diffusive processes and limited by transport and dilution during growth. PMID:25043888

  8. Building the United States National Vegetation Classification

    USGS Publications Warehouse

    Franklin, S.B.; Faber-Langendoen, D.; Jennings, M.; Keeler-Wolf, T.; Loucks, O.; Peet, R.; Roberts, D.; McKerrow, A.

    2012-01-01

    The Federal Geographic Data Committee (FGDC) Vegetation Subcommittee, the Ecological Society of America Panel on Vegetation Classification, and NatureServe have worked together to develop the United States National Vegetation Classification (USNVC). The current standard was accepted in 2008 and fosters consistency across Federal agencies and non-federal partners for the description of each vegetation concept and its hierarchical classification. The USNVC is structured as a dynamic standard, where changes to types at any level may be proposed at any time as new information comes in. But, because much information already exists from previous work, the NVC partners first established methods for screening existing types to determine their acceptability with respect to the 2008 standard. Current efforts include a screening process to assign confidence to Association and Group level descriptions, and a review of the upper three levels of the classification. For the upper levels especially, the expectation is that the review process includes international scientists. Immediate future efforts include the review of remaining levels and the development of a proposal review process.

  9. Ecogeomorphology of Sand Dunes Shaped by Vegetation

    NASA Astrophysics Data System (ADS)

    Tsoar, H.

    2014-12-01

    Two dune types associated with vegetation are known: Parabolic and Vegetated Linear Dunes (VLDs), the latters are the dominant dune type in the world deserts. Parabolic dunes are formed in humid, sub-humid and semi-arid environments (rather than arid) where vegetation is nearby. VLDs are known today in semiarid and arid lands where the average yearly rainfall is ≥100 mm, enough to support sparse cover of vegetation. These two dune types are formed by unidirectional winds although they demonstrate a different form and have a distinct dynamics. Conceptual and mathematical models of dunes mobility and stability, based on three control parameters: wind power (DP), average annual precipitation (p), and the human impact parameter (μ) show that where human impact is negligible the effect of wind power (DP) on vegetative cover is substantial. The average yearly rainfall of 60-80 mm is the threshold of annual average rainfall for vegetation growth on dune sand. The model is shown to follow a hysteresis path, which explains the bistability of active and stabilized dunes under the same climatic conditions with respect to wind power. We have discerned formation of parabolic dunes from barchans and transverse dunes in the coastal plain of Israel where a decrease in human activity during the second half of the 20th century caused establishment of vegetation on the crest of the dunes, a process that changed the dynamics of these barchans and transverse dunes and led to a change in the shape of the windward slope from convex to concave. These dunes gradually became parabolic. It seems that VLDs in Australia or the Kalahari have always been vegetated to some degree, though the shrubs were sparser in colder periods when the aeolian erosion was sizeable. Those ancient conditions are characterized by higher wind power and lower rainfall that can reduce, but not completely destroy, the vegetation cover, leading to the formation of lee (shadow) dunes behind each shrub. Formation of

  10. Topographic Influence on Vegetation Distribution: A Distributed Hydrologic Model with Vegetation Dynamics

    NASA Astrophysics Data System (ADS)

    Bras, R. L.; Ivanov, V. Y.; Vivoni, E. R.

    2005-12-01

    Vegetation can adaptively evolve and respond following seasonal and inter-annual cycles of climate and water redistribution in the system. As a result, it is commonly observed that in semi-arid regions vegetation follows particular patterns, apparently related to topography. In this paper we discuss how vegetation responds to topographically mediated photosyntetically active radiation and soil moisture in a semi-arid climate characteristic of New Mexico. The analysis is done with a new version of the spatially distributed hydrologic model: tRIBS. The latest evolution of the model couples the physics of the principal water and energy processes over the river basin to the basic plant biochemistry. The end result is a fully dynamic representation of vegetation that responds to and influences the spatially variable hydrology. Using the new modeling framework we construct a set of numerical experiments that examine linkages between the catchment geomorphologic structure and patterns of vegetation productivity. The results stress the importance of proper accounting of dynamic vegetation in understanding the water and energy cycles over the basin.

  11. Incineration of Low Level Radioactive Vegetation for Waste Volume Reduction

    SciTech Connect

    Malik, N.P.S.; Rucker, G.G.; Looper, M.G.

    1995-03-01

    The DOE changing mission at Savannah River Site (SRS) are to increase activities for Waste Management and Environmental Restoration. There are a number of Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) locations that are contaminated with radioactivity and support dense vegetation, and are targeted for remediation. Two such locations have been studied for non-time critical removal actions under the National Contingency Plan (NCP). Both of these sites support about 23 plant species. Surveys of the vegetation show that radiation emanates mainly from vines, shrubs, and trees and range from 20,000 to 200,000 d/m beta gamma. Planning for removal and disposal of low-level radioactive vegetation was done with two principal goals: to process contaminated vegetation for optimum volume reduction and waste minimization, and for the protection of human health and environment. Four alternatives were identified as candidates for vegetation removal and disposal: chipping the vegetation and packing in carbon steel boxes (lined with synthetic commercial liners) and disposal at the Solid Waste Disposal Facility at SRS; composting the vegetation; burning the vegetation in the field; and incinerating the vegetation. One alternative `incineration` was considered viable choice for waste minimization, safe handling, and the protection of the environment and human health. Advantages and disadvantages of all four alternatives considered have been evaluated. For waste minimization and ultimate disposal of radioactive vegetation incineration is the preferred option. Advantages of incineration are that volume reduction is achieved and low-level radioactive waste are stabilized. For incineration and final disposal vegetation will be chipped and packed in card board boxes and discharged to the rotary kiln of the incinerator. The slow rotation and longer resident time in the kiln will ensure complete combustion of the vegetative material.

  12. Seepage basin radionuclide transport in sediments and vegetation. Revision 1

    SciTech Connect

    Murphy, C.E. Jr.; Jerome, K.M.

    1993-12-31

    Radionuclide concentrations were measured in soil and vegetation growing adjacent to and in the Savannah River Laboratory Seepage Basins as part of the plan for closure of the basin system. The results of the measurements provide some information about the mobility of the radionuclides introduced into the basins. {sup 90}Sr is the most mobile of the radionuclides in soil. Its high mobility and high relative uptake by vegetation cause {sup 90}Sr to be distributed throughout the basin system. {sup 137}Cs is not as mobile in the basin soil, limiting its uptake by vegetation growing on the edge of the seepage basins; however, it is readily taken up by the vegetation growing in the basins. Soil mobility and vegetation uptake is relatively low for all of the transuranic radionuclides. For the most part these radionuclides remain near the surface of the basin soils where they were absorbed from the waste-water. The relative role of soil mobility and vegetation uptake on the distribution of radionuclide at the basins was futher evaluated by comparing the vegetation concentration ratio and the half-depth of penetration of the radionuclides in the basin soil. The results suggest that vegetation processes dominate in determining the concentration of {sup 60}Co and {sup 137}Cs in the vegetation. The influences of soil and vegetation are more balanced for {sup 90}Sr. The other radionuclides exhibit both low soil mobility and low vegetation uptake. The lack of soil mobility is seen in the lower concentrations found in vegetation growing on the edge of the basin compared to those growing in the basin.

  13. Periodic temporal oscillations in biocrust-vegetation dynamics on sand dunes

    NASA Astrophysics Data System (ADS)

    Yizhaq, Hezi; Ashkenazy, Yosef

    2016-03-01

    We show that the system of biocrust and vegetation on sand dunes modeled by two coupled ordinary nonlinear differential equations exhibits self-sustained oscillations. Such oscillations can occur on vegetated linear dunes that are mostly covered by biocrust. The vegetation-biocrust interaction underlies these oscillations and these do not occur if only vegetation dynamics is considered. The oscillations are "relaxation oscillations" which are characterized by two alternating attraction processes to equilibrium states with high low vegetation covers. The complex dynamics of the biocrust-vegetation model leads to unexpected scenarios, such as vegetation rehabilitation induced by drought or by grazing during which the system shifts to one of the bistable state dominated by a higher vegetation cover, or rehabilitation of vegetation that is induced by decrease in precipitation. The oscillation periods range from decades to millennia and they can interact and be affected by the climate system variability.

  14. Riparian Vegetation Mapping Along the Hanford Reach

    SciTech Connect

    FOGWELL, T.W.

    2003-07-11

    During the biological survey and inventory of the Hanford Site conducted in the mid-1990s (1995 and 1996), preliminary surveys of the riparian vegetation were conducted along the Hanford Reach. These preliminary data were reported to The Nature Conservancy (TNC), but were not included in any TNC reports to DOE or stakeholders. During the latter part of FY2001, PNNL contracted with SEE Botanical, the parties that performed the original surveys in the mid 1990s, to complete the data summaries and mapping associated with the earlier survey data. Those data sets were delivered to PNNL and the riparian mapping by vegetation type for the Hanford Reach is being digitized during the first quarter of FY2002. These mapping efforts provide the information necessary to create subsequent spatial data layers to describe the riparian zone according to plant functional types (trees, shrubs, grasses, sedges, forbs). Quantification of the riparian zone by vegetation types is important to a number of DOE'S priority issues including modeling contaminant transport and uptake in the near-riverine environment and the determination of ecological risk. This work included the identification of vegetative zones along the Reach by changes in dominant plant species covering the shoreline from just to the north of the 300 Area to China Bar near Vernita. Dominant and indicator species included Agropyron dasytachyudA. smithii, Apocynum cannabinum, Aristida longiseta, Artemisia campestris ssp. borealis var scouleriana, Artemisa dracunculus, Artemisia lindleyana, Artemisia tridentata, Bromus tectorum, Chrysothamnus nauseosus, Coreopsis atkinsoniana. Eleocharis palustris, Elymus cinereus, Equisetum hyemale, Eriogonum compositum, Juniperus trichocarpa, Phalaris arundinacea, Poa compressa. Salk exigua, Scirpus acutus, Solidago occidentalis, Sporobolus asper,and Sporobolus cryptandrus. This letter report documents the data received, the processing by PNNL staff, and additional data gathered in FY2002

  15. INTERCOMPARISON OF ALTERNATIVE VEGETATION DATABASES FOR REGIONAL AIR QUALITY MODELING

    EPA Science Inventory

    Vegetation cover data are used to characterize several regional air quality modeling processes, including the calculation of heat, moisture, and momentum fluxes with the Mesoscale Meteorological Model (MM5) and the estimate of biogenic volatile organic compound and nitric oxide...

  16. Parallel Vegetation Stripe Formation Through Hydrologic Interactions

    NASA Astrophysics Data System (ADS)

    Cheng, Y.; Stieglitz, M.; Engel, V.; Turk, G.

    2009-12-01

    vegetation. With time, the patches aggregate and spread laterally in the direction of the downhill flow. To enhance understanding of fundamental processes that govern parallel stripe formation, we employ advanced visualization techniques to improve simulation: Line Integral Convolution for flow visualization and Voronoi Tesselation Algorithm for tracer visualization. We have applied the model to examine ecosystems that are characterized by parallel stripes such as the S&R system in the Everglades (See Engel et al, session H64).

  17. Salt marsh vegetation promotes efficient tidal channel networks

    PubMed Central

    Kearney, William S.; Fagherazzi, Sergio

    2016-01-01

    Tidal channel networks mediate the exchange of water, nutrients and sediment between an estuary and marshes. Biology feeds back into channel morphodynamics through the influence of vegetation on both flow and the cohesive strength of channel banks. Determining how vegetation affects channel networks is essential in understanding the biological functioning of intertidal ecosystems and their ecosystem services. However, the processes that control the formation of an efficient tidal channel network remain unclear. Here we compare the channel networks of vegetated salt marshes in Massachusetts and the Venice Lagoon to unvegetated systems in the arid environments of the Gulf of California and Yemen. We find that the unvegetated systems are dissected by less efficient channel networks than the vegetated salt marshes. These differences in network geometry reflect differences in the branching and meandering of the channels in the network, characteristics that are related to the density of vegetation on the marsh. PMID:27430165

  18. Salt marsh vegetation promotes efficient tidal channel networks.

    PubMed

    Kearney, William S; Fagherazzi, Sergio

    2016-01-01

    Tidal channel networks mediate the exchange of water, nutrients and sediment between an estuary and marshes. Biology feeds back into channel morphodynamics through the influence of vegetation on both flow and the cohesive strength of channel banks. Determining how vegetation affects channel networks is essential in understanding the biological functioning of intertidal ecosystems and their ecosystem services. However, the processes that control the formation of an efficient tidal channel network remain unclear. Here we compare the channel networks of vegetated salt marshes in Massachusetts and the Venice Lagoon to unvegetated systems in the arid environments of the Gulf of California and Yemen. We find that the unvegetated systems are dissected by less efficient channel networks than the vegetated salt marshes. These differences in network geometry reflect differences in the branching and meandering of the channels in the network, characteristics that are related to the density of vegetation on the marsh. PMID:27430165

  19. Use of spectral channels and vegetation indices from satellite VEGETATION time series for the Post-Fire vegetation recovery estimation

    NASA Astrophysics Data System (ADS)

    Coluzzi, Rosa; Lasaponara, Rosa; Montesano, Tiziana; Lanorte, Antonio; de Santis, Fortunato

    2010-05-01

    Satellite data can help monitoring the dynamics of vegetation in burned and unburned areas. Several methods can be used to perform such kind of analysis. This paper is focused on the use of different satellite-based parameters for fire recovery monitoring. In particular, time series of single spectral channels and vegetation indices from SPOT-VEGETATION have investigated. The test areas is the Mediterranean ecosystems of Southern Italy. For this study we considered: 1) the most widely used index to follow the process of recovery after fire: normalized difference vegetation index (NDVI) obtained from the visible (Red) and near infrared (NIR) by using the following formula NDVI = (NIR_Red)/(NIR + Red), 2) moisture index MSI obtained from the near infrared and Mir for characterization of leaf and canopy water content. 3) NDWI obtained from the near infrared and Mir as in the case of MSI, but with the normalization (as the NDVI) to reduce the atmospheric effects. All analysis for this work was performed on ten-daily normalized difference vegetation index (NDVI) image composites (S10) from the SPOT- VEGETATION (VGT) sensor. The final data set consisted of 279 ten-daily, 1 km resolution NDVI S1O composites for the period 1 April 1998 to 31 December 2005 with additional surface reflectance values in the blue (B; 0.43-0.47,um), red (R; 0.61-0.68,um), near-infrared (NIR; 0.78-0.89,um) and shortwave-infrared (SWIR; 1.58-1.75,um) spectral bands, and information on the viewing geometry and pixel status. Preprocessing of the data was performed by the Vlaamse Instelling voor Technologisch Onderzoek (VITO) in the framework of the Global Vegetation Monitoring (GLOVEG) preprocessing chain. It consisted of the Simplified Method for Atmospheric Correction (SMAC) and compositing at ten-day intervals based on the Maximum Value Compositing (MVC) criterion. All the satellite time series were analysed using the Detrended Fluctuation Analysis (DFA) to estimate post fire vegetation recovery

  20. Fruits and vegetables dehydration

    NASA Astrophysics Data System (ADS)

    de Ita, A.; Flores, G.; Franco, F.

    2015-01-01

    Dehydration diagrams were determined by means of Differential Thermal Analysis, DTA, and Thermo Gravimetric Analysis, TGA, curves of several simultaneous fruits and vegetables, all under the same conditions. The greater mass loss is associated with water containing in the structure of the investigated materials at low temperature. In poblano chile water is lost in a single step. The banana shows a very sharply two stages, while jicama can be observed although with a little difficulty three stages. The major mass loss occurs in the poblano chile and the lower in banana. The velocity and temperature of dehydration vary within a small range for most materials investigated, except for banana and cactus how are very different.

  1. Monitoring tropical vegetation succession with LANDSAT data

    NASA Technical Reports Server (NTRS)

    Robinson, V. B. (Principal Investigator)

    1983-01-01

    The shadowing problem, which is endemic to the use of LANDSAT in tropical areas, and the ability to model changes over space and through time are problems to be addressed when monitoring tropical vegetation succession. Application of a trend surface analysis model to major land cover classes in a mountainous region of the Phillipines shows that the spatial modeling of radiance values can provide a useful approach to tropical rain forest succession monitoring. Results indicate shadowing effects may be due primarily to local variations in the spectral responses. These variations can be compensated for through the decomposition of the spatial variation in both elevation and MSS data. Using the model to estimate both elevation and spectral terrain surface as a posteriori inputs in the classification process leads to improved classification accuracy for vegetation of cover of this type. Spatial patterns depicted by the MSS data reflect the measurement of responses to spatial processes acting at several scales.

  2. Vegetable oils as fuel alternatives - symposium overview

    SciTech Connect

    Pryde, E.H.

    1984-10-01

    Several encouraging statements can be made about the use of vegetable oil products as fuel as a result of the information presented in these symposium papers. Vegetable oil ester fuels have the greatest promise, but further engine endurance tests will be required. These can be carried out best by the engine manufacturers. Microemulsions appear to have promise, but more research and engine testing will be necessary before performance equivalent to the ester fuels can be developed. Such research effort can be justified because microemulsification is a rather uncomplicated physical process and might be adaptable to on-farm operations, which would be doubtful for the more involved transesterfication process. Although some answers have been provided by this symposium, others are still not available; engine testing is continuing throughout the world particularly in those countries that do not have access to petroleum. 9 references.

  3. Predicting Vegetation Patterning across Climate, Soil, and Topographic Gradients

    NASA Astrophysics Data System (ADS)

    Axelsson, C.; Hanan, N. P.

    2014-12-01

    Vegetation communities in water-limited systems sometimes form periodic patterns, e.g. banded, spotted and labyrinthine distributions of woody and herbaceous plants. Pattern formation is commonly linked to competition and facilitation among plants, and variation in runoff and infiltration capacity in the landscape. Based on previous studies, we expect that climate, soil type, and slope to a large degree influence the type of vegetation pattern found at a specific site. We have analyzed to what extent vegetation patterns on the African continent can be predicted based on available climatic, topographic, and soil data. Our focus is not restricted to periodic patterns in drylands, but encompasses a range of tropical ecosystems from arid to humid. Vegetation patterns observed in remote sensing data can be informative regarding the underlying ecological processes that shape the landscape, not only in strikingly periodic vegetation but also in savannas with randomly located or dispersed vegetation. We use high-resolution multispectral and panchromatic remote sensing data classified into woody, herbaceous, and bare ground components. From these images we extract spatial statistical metrics that define type and degree of vegetation patterning. We then relate variables from climate, soil and topographic datasets to the observed patterns in order to determine how well we can predict vegetation patterning and which climatic and edaphic variables are most informative. We discuss the results and the possible sources of uncertainty in the relationships.

  4. Assessment of Stage of Change, Decisional Balance, Self-Efficacy, and Use of Processes of Change of Low-Income Parents for Increasing Servings of Fruits and Vegetables to Preschool-Aged Children

    ERIC Educational Resources Information Center

    Hildebrand, Deana A.; Betts, Nancy M.

    2009-01-01

    Objective: Use the Transtheoretical Model of Behavior Change (TTM) to determine the proportionate stage of change of low-income parents and primary caregivers (PPC) for increasing accessibility, measured as servings served, of fruits and vegetables (FV) to their preschool-aged children and evaluate response differences for theoretical constructs.…

  5. Evolution of vegetated waterways design

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 1990, the USDA-ARS Hydraulic Engineering Research Unit (HERU) was recognized as a National Historic Landmark by ASABE for its groundbreaking work and development of vegetated waterways design procedures. In 2000, ASABE acknowledged the vegetated waterway design criteria as an Outstanding Achieve...

  6. Increasing vegetable consumption in adolescents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Studies have demonstrated that diets rich in vegetables may protect against many chronic diseases and overweight. Despite these benefits, consumption in children and adolescents is well below recommended levels. Finding methods to increase vegetable consumption in adolescents is important. Our objec...

  7. Behavior of glucosinolates in pickling cruciferous vegetables.

    PubMed

    Suzuki, Chise; Ohnishi-Kameyama, Mayumi; Sasaki, Keisuke; Murata, Takashi; Yoshida, Mitsuru

    2006-12-13

    Crucifer species, which include widely consumed vegetables, contain glucosinolates as secondary metabolites. Cruciferous vegetables are consumed in Japan in salt-preserved or pickled form as well as cooked and raw fresh vegetables. In this study, changes in contents of glucosinolates during the pickling process were investigated. 4-Methylthio-3-butenyl glucosinolate, a major glucosinolate in the root of Japanese radish, daikon (Raphanus sativus L.), was detected in pickled products with a short maturation period but not in those with a long maturation period. As a model pickling experiment, fresh watercress (Nasturtium officinale) and blanched watercress were soaked in 3% NaCl solution for 7 days. The results showed that the ratio of indole glucosinolates to total glucosinolates increased during the pickling process, whereas total glucosinolates decreased. Myrosinase digestion of glucosinolates in nozawana (Brassica rapa L.) indicated that indole glucosinolates, especially 4-methoxyglucobrassicin, were relatively resistant to the enzyme. The effect of pickling on glucosinolate content and the possible mechanism are discussed in view of degradation by myrosinase and synthetic reaction in response to salt stress or compression during the pickling process. PMID:17147429

  8. Climate Change Impacts on Turkish Vegetation

    NASA Astrophysics Data System (ADS)

    Forrest, Matthew; Dönmez, Cenk; Çilek, Ahmet; Akif Erdogan, Mehmet; Buontempo, Carlo; Hickler, Thomas

    2014-05-01

    The Mediterranean has been identified as a potentially vulnerable hotspot under climate change. In Turkey, climate change projections consistently predict large temperature rises over the 21st century. With 9% of GDP and 25% of employment coming from agriculture, climate change has the potential to significantly affect both the Turkish economy and living standards. Relatively little work has been undertaken to estimate the effects and risks of climate change in Turkey, and many European studies cover do not include the whole of Turkey in their domain and so are of limited use for policy-makers. The Dynamic Global Vegetation Model LPJ-GUESS was parametrised to represent Turkish vegetation. Climate forcings were derived by interpolating meteorological data from over 600 stations from 1975-2010 to a 1km resolution. Soil depth and soil texture data from field measurements were also interpolated to a 1km grid. The model was benchmarked against vegetation type and remotely sensed biomass and tree cover data. Future climate conditions were calculated using the outputs from a set of regional model simulations. In particular the HadRM3P regional climate model was used to downscale five members of a perturbed physics ensemble of global climate projections obtained using HadCM3 general circulation model and the SRES A1B scenario. A delta change factor approach was then used in conjunction with the observed climate data to assess the impact on vegetation structure and ecological processes to the year 2100 using LPJ-GUESS. The resulting changes to productivity, vegetation structure and hydrology are discussed. Eventually these results will be combined with complementary studies concerning wildfire and erosion to produce a risk map for informing policy-makers.

  9. Classification of wetlands vegetation using small scale color infrared imagery

    NASA Technical Reports Server (NTRS)

    Williamson, F. S. L.

    1975-01-01

    A classification system for Chesapeake Bay wetlands was derived from the correlation of film density classes and actual vegetation classes. The data processing programs used were developed by the Laboratory for the Applications of Remote Sensing. These programs were tested for their value in classifying natural vegetation, using digitized data from small scale aerial photography. Existing imagery and the vegetation map of Farm Creek Marsh were used to determine the optimal number of classes, and to aid in determining if the computer maps were a believable product.

  10. An experimental study of flow around submerged grass vegetation

    NASA Astrophysics Data System (ADS)

    Lee, Julia; Mandre, Shreyas; Singh, Ravi

    2014-11-01

    Mixing of fluids through submerged vegetation caused by tidal currents facilitate various environmental and ecological transport processes. This fluid-vegetation interaction is believed to result from a Kelvin-Helmholtz instability from an inflection point in the flow profile. Recent studies suggest that flow in presence of grass can also become unstable due to shear instability of flow above the grass. We devise a two-dimensional lab scale analog of the fluid-vegetation interaction using ABS plastic filaments immersed in a soap film. We employ PIV of the surrounding flow to gain an understanding of the role of instabilities in the flow.

  11. How to deal with radiologically contaminated vegetation

    SciTech Connect

    Wilde, E.W.; Murphy, C.E.; Lamar, R.T.; Larson, M.J.

    1996-12-31

    This report describes the findings from a literature review conducted as part of a Department of Energy, Office of Technology Development Biomass Remediation Task. The principal objective of this project is to develop a process or group of processes to treat radiologically contaminated vegetation in a manner that minimizes handling, processing, and treatment costs. Contaminated, woody vegetation growing on waste sites at SRS poses a problem to waste site closure technologies that are being considered for these sites. It is feared that large sections of woody vegetation (logs) can not be buried in waste sites where isolation of waste is accomplished by capping the site. Logs or large piles of woody debris have the potential of decaying and leaving voids under the cap. This could lead to cap failure and entrance of water into the waste. Large solid objects could also interfere with treatments like in situ mixing of soil with grout or other materials to encapsulate the contaminated sediments and soils in the waste sites. Optimal disposal of the wood includes considerations of volume reduction, treatment of the radioactive residue resulting from volume reduction, or confinement without volume reduction. Volume reduction consists primarily of removing the carbon, oxygen, and hydrogen in the wood, leaving an ash that would contain most of the contamination. The only contaminant that would be released by volume reduction would by small amounts of the radioactive isotope of hydrogen, tritium. The following sections will describe the waste sites at SRS which contain contaminated vegetation and are potential candidates for the technology developed under this proposal. The description will provide a context for the magnitude of the problem and the logistics of the alternative solutions that are evaluated later in the review. 76 refs.

  12. Floating particle trapping and diffusion in vegetated open channel flow

    NASA Astrophysics Data System (ADS)

    Defina, Andrea; Peruzzo, Paolo

    2010-11-01

    In this paper we present early results of laboratory experiments to investigate the transport and diffusion of floating particles (e.g., buoyant seeds) in open channel flow with emergent vegetation. The experiments are aimed at providing a better understanding of the relevant particle-vegetation interaction mechanisms responsible for the observed diffusion processes. Qualitative observational data are then used to set up a stochastic model for floating particle transport and diffusion. Quantitative observations, such as the distribution of distances travelled by a particle before it is permanently captured by a plant and the arrival-time distributions at prescribed cross sections along the vegetated test section, are instead used to calibrate and validate the model. The comparison between theoretical predictions and experimental results is quite satisfactory and suggests that the observed relevant aspects of the particle-vegetation interaction processes are properly described in the model.

  13. Calcium biofortification and bioaccessibility in soilless "baby leaf" vegetable production.

    PubMed

    D'Imperio, Massimiliano; Renna, Massimiliano; Cardinali, Angela; Buttaro, Donato; Serio, Francesco; Santamaria, Pietro

    2016-12-15

    Calcium is an essential nutrient for human health, because it is a structural component and takes part in a variety of biological processes. The aim of this study was to increase Ca content of baby leaf vegetables (BLV: basil, mizuna, tatsoi and endive), as fresh-cut products. For the production of biofortified BLV, a floating system with two level of Ca (100 and 200mgL(-1)) in the nutrient solution was used. In addition, the assessment of bioaccessibility of Ca, by in vitro digestion process, was performed. In all vegetables, the Ca biofortification (200mgL(-1)) caused a significant Ca enrichment (9.5% on average) without affecting vegetables growth, oxalate contents and marketable quality. Calcium bioaccessibility ranged from 25% (basil) to 40% (endive) but the biofortified vegetables showed more bioaccessible Ca. These results underline the possibility to obtain Ca biofortified BLV by using agronomic approaches. PMID:27451166

  14. Carboniferous coal swamp vegetation

    SciTech Connect

    Phillips, T.L.; Peppers, R.A.; DiMichele, W.A.

    1984-01-01

    The Carboniferous Period was one of considerable change on the Earth. The volume explores these changes by using plant morphology and paleoecology to develop the relationship between plant evolution and the derived coal sources. Both are interrelated by the regional and stratigraphic trends in paleoecology and paleoclimatology. The book is divided into three sections dealing with geology, plant morphology including palynology, and paleoecology. In Section I, the paleogeography, geologic settings of major coal basins, coal resources, coal-ball origins and occurrences, and the sources of paleobotanical information are presented with biostratigraphic correlations of Europe and the United States. Section II emphasizes plant morphology as form and structure provide the means of identifying plants and, in turn, establishing development, size, habit, reproductive biology, environmental parameters, and evolutionary change. Quantitative abundances and stratigraphic ranges of plants and spores are compared and summarized. Lastly, Section III integrates coal-ball peats and coal-spore floras as complementary sources for the quantitative analyses of coal-swamp vegetation in relation to climate and coal. The local and regional swamp studies are interfaced and basinal geology and depositional interpretations in a stratigraphic succession.

  15. Dielectric properties of marsh vegetation

    NASA Astrophysics Data System (ADS)

    Kochetkova, Tatiana D.; Suslyaev, Valentin I.; Shcheglova, Anna S.

    2015-10-01

    The present work is devoted to the measurement of the dielectric properties of mosses and lichens in the frequency range from 500 MHz to 18 GHz. Subjects of this research were three species of march vegetation - moss (Dicranum polysetum Michx), groundcedar (Diphasiastrum complanatum (L.) Holub) and lichen (Cladonia stellaris). Samples of vegetation were collected in Tomsk region, Western Siberia, Russia. Complex dielectric permittivity was measured in coaxial section by Agilent Technologies vector network analyzer E8363B. Green samples was measured for some moisture contents from 100% to 3-5 % during a natural drying. The measurements were performed at room temperature, which remained within 21 ÷ 23 ° C. The frequency dependence of the dielectric constant for the three species of marsh vegetation differ markedly. Different parts of the complex permittivity dependency on moisture were fitted by line for all frequency points. Two break point were observed corresponding to the transition of water in the vegetation in various phase states. The complex permittivity spectra of water in the vegetation allow determining the most likely corresponding dielectric model of water in the vegetation by the method of hypothesis testing. It is the Debye's model. Parameters of Debye's model were obtained by numerical methods for all of three states of water. This enables to calculate the dielectric constant of water at any frequency range from 500 MHz to 18 GHz and to find the parameters of the dielectric model of the vegetation.

  16. Green vegetation, nonphotosynthetic vegetation, and soils in AVIRIS data

    NASA Technical Reports Server (NTRS)

    Roberts, D. A.; Smith, M. O.; Adams, J. B.

    1993-01-01

    The problem of distinguishing between green vegetation, nonphotosynthetic vegetation (NPV, such as dry grass, leaf litter, and woody material), and soils in imaging-spectrometer data is addressed by analyzing an image taken by the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) over the Jasper Ridge Biological Preserve (California) on September 20, 1989, using spectral mixture analysis. Over 98 percent of the spectral variation could be explained by linear mixtures of three endmembers, green vegetation, shade, and soil. NPV, which could not be distinguished from soil when included as an endmember, was discriminated by residual spectra that contained cellulose and lignin absorptions. Distinct communities of green vegetation were distinguished by (1) nonlinear mixing effect caused by transmission and scattering by green leaves, (2) variations in a derived canopy-shade spectrum, and (3) the fraction of NPV.

  17. Climate Change Implications to Vegetation Production in Alaska

    NASA Astrophysics Data System (ADS)

    Neigh, C. S.

    2008-12-01

    Investigation of long-term NOAA series of Advanced Very High Resolution Radiometer normalized difference vegetation index (NDVI) data from 1982 through 2005 revealed statistically significant vegetation response to climate drivers of temperature, precipitation and solar radiation with exclusion of fire disturbance. Abiotic trends were calculated and correlated to satellite remote sensing observations of vegetation productivity to understand biophysical processes that could impact ecosystem carbon storage. Warming throughout Alaska resulted in disparate trajectories for vegetation growth due to precipitation and photosynthetically active radiation variation. Interior spruce forest low lands in late summer had precipitation deficit which resulted in extensive fire disturbance and browning of undisturbed vegetation with reduced post-fire recovery in burned sites; while Northern slope alpine and moist tundra had increased production due to warmer-wetter conditions during the late 1990s and early 2000s. Coupled investigation of vegetation's response to warming climate in Alaska found spatially dynamic processes with and without fire disturbance observed from coarse resolution satellite instruments. Future effort will simulate carbon cycle process with fire disturbance to understand spatially variant source-sink distribution of Alaskan ecosystems.

  18. Vegetation Description, Rare Plant Inventory, and Vegetation Monitoring for Craig Mountain, Idaho.

    SciTech Connect

    Mancuso, Michael; Moseley, Robert

    1994-12-01

    The Craig Mountain Wildlife Mitigation Area was purchased by Bonneville Power Administration (BPA) as partial mitigation for wildlife losses incurred with the inundation of Dworshak Reservoir on the North Fork Clearwater River. Upon completion of the National Environmental Protection Act (NEPA) process, it is proposed that title to mitigation lands will be given to the Idaho Department of Fish and Game (IDFG). Craig Mountain is located at the northern end of the Hells Canyon Ecosystem. It encompasses the plateau and steep canyon slopes extending from the confluence of the Snake and Salmon rivers, northward to near Waha, south of Lewiston, Idaho. The forested summit of Craig Mountain is characterized by gently rolling terrain. The highlands dramatically break into the canyons of the Snake and Salmon rivers at approximately the 4,700 foot contour. The highly dissected canyons are dominated by grassland slopes containing a mosaic of shrubfield, riparian, and woodland habitats. During the 1993 and 1994 field seasons, wildlife, habitat/vegetation, timber, and other resources were systematically inventoried at Craig Mountain to provide Fish and Game managers with information needed to draft an ecologically-based management plan. The results of the habitat/vegetation portion of the inventory are contained in this report. The responsibilities for the Craig Mountain project included: (1) vegetation data collection, and vegetation classification, to help produce a GIS-generated Craig Mountain vegetation map, (2) to determine the distribution and abundance of rare plants populations and make recommendations concerning their management, and (3) to establish a vegetation monitoring program to evaluate the effects of Fish and Game management actions, and to assess progress towards meeting habitat mitigation goals.

  19. Analyzing nonlinear variations in terrestrial vegetation in China during 1982-2012.

    PubMed

    Liu, Yanxu; Liu, Xianfeng; Hu, Yi'na; Li, Shuangshuang; Peng, Jian; Wang, Yanglin

    2015-11-01

    Quantifying the long-term trends of changes in terrestrial vegetation on a large scale is an effective method for detecting the effects of global environmental change. In view of the trend towards overall restoration and local degradation of terrestrial vegetation in China, it is necessary to pay attention to the spatial processes of vegetative restoration or degradation, as well as to clarify the temporal and spatial characteristics of vegetative growth in greater geographical detail. However, traditional linear regression analysis has some drawbacks when describing ecological processes. Combining nonparametric linear regression analysis with high-order nonlinear fitting, the temporal and spatial characteristics of terrestrial vegetative growth in China during 1982-2012 were detected using the third generation of Global Inventory Modeling and Mapping Studies (GIMMS3g) dataset. The results showed that high-order curves could be effective. The region joining Ordos City and Shaanxi Gansu Ningxia on the Loess Plateau may have experienced restoration-degradation-restoration processes of vegetative growth. In the Daloushan Mountains, degradation-restoration processes of vegetative growth may have occurred, and the occurrence of several hidden vegetative growth processes was located in different regions of eastern China. Changes in cultivated vegetation were inconsistent with changes in other vegetation types. In southern China and some high-altitude areas, temperature was the primary driver of vegetative growth on an interannual scale, while in the north, the effect of rainfall was more significant. Nevertheless, the influence of climate on vegetation activity in large urban areas was weak. The trend types of degradation-restoration processes in several regions were inconsistent with the implements of regional land development and protection strategy. Thus, the role of human activity cannot be ignored. In future studies, it will be still necessary to quantify the

  20. Late-quaternary vegetational dynamics and community stability reconsidered

    NASA Astrophysics Data System (ADS)

    Delcourt, Paul A.; Delcourt, Hazel R.

    1983-03-01

    Defining the spatial and temporal limits of vegetational processes such as migration and invasion of established communities is a prerequisite to evaluating the degree of stability in plant communities through the late Quaternary. The interpretation of changes in boundaries of major vegetation types over the past 20,000 yr offers a complementary view to that provided by migration maps for particular plant taxa. North of approximately 43°N in eastern North America, continual vegetational disequilibrium has resulted from climatic change, soil development, and species migrations during postglacial times. Between 33° and 39°N, stable full-glacial vegetation was replaced by a relatively unstable vegetation during late-glacial climatic amelioration; stable interglacial vegetation developed there after about 9000 yr B.P. Late-Quaternary vegetation has been in dynamic equilibrium, with a relatively constant flora, south of 33°N on upland interfluves along the northern Gulf Coastal Plain, peninsular Florida, and west-central Mexico.

  1. Monitoring vegetation growth and morphodynamic effects after stream restoration

    NASA Astrophysics Data System (ADS)

    Vargas-Luna, Andrés; Crosato, Alessandra; Anders, Niels; Hoitink, Ton; Keesstra, Saskia; Uijttewaal, Wim

    2016-04-01

    Vegetation processes are widely recognized as a key component on the ecological and morphological development of river channels. Moreover, plants reduce flow velocities and bed-shear stresses by increasing the local hydraulic roughness and thus increasing water levels. Therefore, monitoring the vegetation development is an important activity in river management not only for protecting ecological services, but also in flood risk reduction; especially in times of a changing climate. This paper presents the analysis the effects of riparian vegetation growth on the morphology of a lowland restored stream located in The Netherlands, the Lunterse beek. An Unmanned Aerial Vehicle (UAV) was used to obtain aerial imagery at different time steps which was the basis for generating land cover maps with semi-automated image classification. In addition hydrological series and multi-temporal high-resolution bathymetric data allowed analysing river bed morphology and the relevance of seasonality. The UAV campaigns were found a crucial step to ease the vegetation mapping and monitoring. The morphological change observed in this stream, represented by the channel-width adjustment and the cross sectional evolution, is slowed down once vegetation is stablished on the stream. Results of this work show that the vegetation root system assert a strong control on soil stabilization, even during the winter season when the plants biomass is highly reduced. Seasonal variations in plant development appear important only during the first stages of establishment, when vegetation has a low density and, more importantly, a root system that is not fully developed yet.

  2. Pesticides on fruits and vegetables

    MedlinePlus

    ... option, you may want to buy and serve organic produce. Organic growers do not use pesticides on their fruits ... To remove harmful bacteria, you must wash both organic and nonorganic fruits and vegetables.

  3. The Circumpolar Arctic vegetation map

    USGS Publications Warehouse

    Walker, Donald A.; Raynolds, Martha K.; Daniels, F.J.A.; Einarsson, E.; Elvebakk, A.; Gould, W.A.; Katenin, A.E.; Kholod, S.S.; Markon, C.J.; Melnikov, E.S.; Moskalenko, N.G.; Talbot, S. S.; Yurtsev, B.A.; Bliss, L.C.; Edlund, S.A.; Zoltai, S.C.; Wilhelm, M.; Bay, C.; Gudjonsson, G.; Ananjeva, G.V.; Drozdov, D.S.; Konchenko, L.A.; Korostelev, Y.V.; Ponomareva, O.E.; Matveyeva, N.V.; Safranova, I.N.; Shelkunova, R.; Polezhaev, A.N.; Johansen, B.E.; Maier, H.A.; Murray, D.F.; Fleming, Michael D.; Trahan, N.G.; Charron, T.M.; Lauritzen, S.M.; Vairin, B.A.

    2005-01-01

    Question: What are the major vegetation units in the Arctic, what is their composition, and how are they distributed among major bioclimate subzones and countries? Location: The Arctic tundra region, north of the tree line. Methods: A photo-interpretive approach was used to delineate the vegetation onto an Advanced Very High Resolution Radiometer (AVHRR) base image. Mapping experts within nine Arctic regions prepared draft maps using geographic information technology (ArcInfo) of their portion of the Arctic, and these were later synthesized to make the final map. Area analysis of the map was done according to bioclimate subzones, and country. The integrated mapping procedures resulted in other maps of vegetation, topography, soils, landscapes, lake cover, substrate pH, and above-ground biomass. Results: The final map was published at 1:7 500 000 scale map. Within the Arctic (total area = 7.11 x 106 km 2), about 5.05 ?? 106 km2 is vegetated. The remainder is ice covered. The map legend generally portrays the zonal vegetation within each map polygon. About 26% of the vegetated area is erect shrublands, 18% peaty graminoid tundras, 13% mountain complexes, 12% barrens, 11% mineral graminoid tundras, 11% prostrate-shrub tundras, and 7% wetlands. Canada has by far the most terrain in the High Arctic mostly associated with abundant barren types and prostrate dwarf-shrub tundra, whereas Russia has the largest area in the Low Arctic, predominantly low-shrub tundra. Conclusions: The CAVM is the first vegetation map of an entire global biome at a comparable resolution. The consistent treatment of the vegetation across the circumpolar Arctic, abundant ancillary material, and digital database should promote the application to numerous land-use, and climate-change applications and will make updating the map relatively easy. ?? IAVS; Opulus Press.

  4. Vegetation ecogeomorphology, dynamic equilibrium, and disturbance: chapter 7

    USGS Publications Warehouse

    Hupp, Cliff R.

    2013-01-01

    Early ecologists understood the need to document geomorphic form and process to explain plant species distributions. Although this relationship has been acknowledged for over a century, with the exception of a few landmark papers, only the past few decades have experienced intensive research on this interdisciplinary topic. Here the authors provide a summary of the intimate relations between vegetation and geomorphic/process on hillslopes and fluvial systems. These relations are separated into systems (primarily fluvial) in dynamic equilibrium and those that are in nonequilibrium conditions including the impacts of various human disturbances affecting landforms, geomorphic processes, and interrelated, attendant vegetation patterns and processes. The authors conclude with a conceptual model of stream regime focusing on sediment deposition, erosion, and equilibrium that can be expanded to organize and predict vegetation patterns and life history strategies.

  5. Estimating fractional vegetation cover (FVC) using satellite vegetation indices and digital photo image in Mongolia

    NASA Astrophysics Data System (ADS)

    Kim, J.

    2015-12-01

    Fractional vegetation cover (FVC) is a useful index of monitoring land cover dynamics and land surface energy partitioning into sensible and latent heats from satellite because it can be estimated by using satellite-based spectral vegetation indices (VI), such as NDVI and EVI. The relationship between FVC and vegetation indices is however variable depending on regional vegetation types and background soil types across different regions. In particular, arid and semi-arid region shows substantial uncertainty in the VI-FVC relations because of sparse vegetation cover and hence, important roles of local soil type in land-surface spectral reflectance. In this study, VI-FVC relations were investigated for arid and semi-arid regions of Mongolia. The FVC data was prepared from digital-camera image interpretation sheets taken at 160 sites in our field excursions from 2012 to 2014. In comparisons with visual inspections, the camera-based FVC showed good linear relations (r = 0.97, p < 0.001) with 6.83% of RMSE. Three satellite-based VIs were prepared, i.e. MODIS NDVI, EVI, and SAVI, which applied to produce linear regression models of FVC. The model parameters (i.e. slope and intercept) was obtained through iterated calculation process. Among the 160 sites, 120 sites were arbitrarily extracted to produce regression model and the remaining 40 sites were used for model validation. This iterated process were repeated 1,000,000 times and then, statistics were derived as averages of model (slope and interception) and validation (Pearson correlation coefficient and RMSE). In results, the regression models generally showed good agreements in model validations over r = 0.8 (p < 0.001). This study discussed problems in long-term FVC retrieval for the arid and semi-arid regions of Mongolia.

  6. Prevalence of Salmonella in vegetables from Mexico.

    PubMed

    Quiroz-Santiago, Carolina; Rodas-Suárez, Oscar R; Carlos R, Vázquez; Fernández, Francisco J; Quiñones-Ramírez, Elsa Irma; Vázquez-Salinas, Carlos

    2009-06-01

    The present study is an overview of the role of vegetables as a transmission vehicle of Salmonella in Mexico. One hundred samples of each of 17 different vegetables were analyzed during a period of 18 months. Salmonella was isolated from 98 samples. Salmonella enterica serovar Typhimurium was isolated from the highest percentage of samples with typeable Salmonella isolates (23.9%), followed by S. enterica subsp. arizonae and Salmonella Choleraesuis each from 16.9%, Salmonella Gallinarum from 11.1%, Salmonella Anatum and S. enterica subsp. houtenae each from 9.7%, Salmonella Agona and Salmonella Edinburg each from 4.22%, Salmonella Enteritidis and S. enterica subsp. salamae each from 2.81%, and Salmonella Bongor, Salmonella Pullorum, Salmonella Typhi, and Salmonella C1 flagellar b each from 1.4%. Of the isolated bacteria, 27.6% were nontypeable strains. Salmonella was isolated from 12% of parsley samples, 11% of cilantro samples, 9% of broccoli samples, 9% of cauliflower samples, 9% of "papaloquelite" (Porophyllum ruderale) samples, 9% of purslane (Portulaca oleracea) samples, 7% of long lettuce samples, 7% of spinach samples, 7% of watercress samples, 6% of Chinese parsley samples, 4% of beet samples, 3% of celery samples, 3% of Romaine lettuce samples, 1% of cabbage samples, and 1% of potato samples. The presence of Salmonella Typhi in parsley is noteworthy. No Salmonella isolates were obtained from zucchini and onion. These results indicate that raw or minimally processed vegetables can be contaminated with Salmonella, leading to direct infection of consumers or cross-contamination of other foodstuffs. These contaminated vegetables can represent a severe health risk for the Mexican consumer. PMID:19610340

  7. The soil water balance in a mosaic of clumped vegetation

    NASA Astrophysics Data System (ADS)

    Pizzolla, Teresa; Manfreda, Salvatore; Caylor, Kelly; Gioia, Andrea; Iacobellis, Vito

    2014-05-01

    The spatio-temporal distribution of soil moisture influences the plant growth and the distribution of terrestrial vegetation. This effect is more evident in arid and semiarid ecosystems where the interaction between individuals and the water limited conditions play a fundamental role, providing environmental conditions which drive a variety of non-linear ecohydrological response functions (such as transpiration, photosynthesis, leakage). In this context, modeling vegetation patterns at multiple spatial aggregation scales is important to understand how different vegetation structures can modify the soil water distribution and the exchanged fluxes between soil and atmosphere. In the present paper, the effect of different spatial vegetation patterns, under different climatic scenarios, is investigated in a patchy vegetation mosaic generated by a random process of individual tree canopies and their accompanying root system. Vegetation pattern are generated using the mathematical framework proposed by Caylor et al. (2006) characterized by a three dimensional stochastic vegetation structure, based on the density, dispersion, size distribution, and allometry of individuals within a landscape. A Poisson distribution is applied to generate different distribution of individuals paying particular attention on the role of clumping on water distribution dynamics. The soil water balance is evaluated using the analytical expression proposed by Laio et al. (2001) to explore the influence of climate and vegetation patterns on soil water balance steady-state components (such as the average rates of evaporation, the root water uptake and leakage) and on the stress-weighted plant water uptake. Results of numerical simulations show that clumping may be beneficial for water use efficiency at the landscape scale. References Caylor, Kelly K., P. D'Odorico and I. Rodriguez Iturbe: On the ecohydrology of structurally heterogeneous semiarid landscape. Water Resour. Res., 28, W07424, 2006

  8. 18 CFR 1304.203 - Vegetation management.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 2 2011-04-01 2011-04-01 false Vegetation management...-Owned Residential Access Shoreland § 1304.203 Vegetation management. No vegetation management shall be approved on TVA-owned Residential Access Shoreland until a Vegetation Management Plan meeting...

  9. 18 CFR 1304.203 - Vegetation management.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Vegetation management...-Owned Residential Access Shoreland § 1304.203 Vegetation management. No vegetation management shall be approved on TVA-owned Residential Access Shoreland until a Vegetation Management Plan meeting...

  10. 18 CFR 1304.203 - Vegetation management.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 2 2012-04-01 2012-04-01 false Vegetation management...-Owned Residential Access Shoreland § 1304.203 Vegetation management. No vegetation management shall be approved on TVA-owned Residential Access Shoreland until a Vegetation Management Plan meeting...

  11. 18 CFR 1304.203 - Vegetation management.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 2 2014-04-01 2014-04-01 false Vegetation management...-Owned Residential Access Shoreland § 1304.203 Vegetation management. No vegetation management shall be approved on TVA-owned Residential Access Shoreland until a Vegetation Management Plan meeting...

  12. 18 CFR 1304.203 - Vegetation management.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 2 2013-04-01 2012-04-01 true Vegetation management...-Owned Residential Access Shoreland § 1304.203 Vegetation management. No vegetation management shall be approved on TVA-owned Residential Access Shoreland until a Vegetation Management Plan meeting...

  13. Thermal properties for vegetation cover

    NASA Astrophysics Data System (ADS)

    Aleksyutina, D.; Motenko, R.

    2011-12-01

    Different samples of undisturbed vegetation cover were studied under laboratory conditions. Samples were collected from New Chara city, north of the Chita region. Vegetation cover in this area is represented by moss, lichen and tussock growth. Thermal properties were investigated by the I-st type regular mode method (a-calorimeter), the freezing temperature was studied by cryoscopic methods. The dry density of sampled specimens varies from 0.04 to 0.24 g/cm3, and humidity varies from 250 to 375 percent. The freezing temperature depends on moisture content and varies from -0.2 to 0 degrees centigrade. The vegetation cover had low thermal conductivities which varies from 0.05 to 0.46 W/(m*K) in unfrozen conditions, and from 0.07 to 1.14 W/(m*K) in frozen conditions, according to density and moisture content. Diffusivity of samples varies from 0.073*10-6 to 0.114*10-6 m2/s in thawed conditions, and from 0.174*10-6 to 0.584*10-6 m2/s in frozen conditions. The sod (bottom of vegetation cover) had relatively high thermal properties. Thermal properties of vegetation cover and peat (turf) were compared. The thermal conductivity of peat was much higher than thermal conductivity of vegetation cover. This data may be used for modeling of the thickness of the seasonally thawed layer and ground temperature variation. The knowledge of thermal properties of these samples allows us to view vegetation cover as a separate layer of geological section.

  14. Vegetation disturbance and maintenance of diversity in intermittently flooded Carolina Bays in South Carolina

    SciTech Connect

    Kirkman, L.K.; Sharitz, R.R. )

    1994-02-01

    The authors manipulated the fire regime and soil disturbance in four grass-dominated Carolina bay wetlands during a prolonged drought period and examined vegetation composition and cover within dominant vegetation types prior to and after treatments. The authors used the seedling emergence technique to determine the role of the seed bank in the recovery process. Burning did not affect richness, evenness, or diversity (all vegetation types combined); however, soil tillage increased diversity, including both evenness and richness. Percent similarity of the vegetation before and after disturbance was greater in the burning treatment than in the tillage treatment, probably due to greater disruption of the rhizomes of the perennial vegetation by tillage. Vegetation types varied in degree of recovery, although dominance was not altered by either treatment. Several native fugitive species increased following disturbance, indicating that species coexistence in these Carolina bay wetlands depends on the life history characteristics of residual vegetation, as well as that of seed bank species.

  15. Vegetable Dyeing of Wool

    ERIC Educational Resources Information Center

    Greenberg, Pearl

    1976-01-01

    In keeping with the Bicentennial celebration, many art teachers will find themselves "looking back" to crafts of the American past. Dyeing is certainly one that was used extensively and here a professor in a Fine Arts Department details how the process takes place. (Author/RK)

  16. BIOMONITORING USING AQUATIC VEGETATION

    EPA Science Inventory

    This chapter provides an overview of the state-of-the-science as related to the phytoassessment techniques used in environmental biomonitoring and the hazard assessment process for chemicals. The emphasis is on freshwater angiosperms and bryophytes. Algal species, which are prese...

  17. Sand Bed Morphodynamics under Standing Waves and Vegetated Conditions

    NASA Astrophysics Data System (ADS)

    Landry, B. J.; Garcia, M. H.

    2010-12-01

    Littoral processes such as sediment transport, wave attenuation, and boundary layer development are governed by the presence of bathymetric features, which include large-scale sand bars upon which smaller-scale sand ripples are superimposed, as well as the presence of submarine vegetation. Numerous studies on sand ripples and bars have aided to elucidate the dynamics in oscillatory flows; however, the effect of vegetation on the system is less understood. Recent laboratory studies have focused on quantifying wave attenuation by emergent vegetation as a natural method to mitigate storm surges. The emergent vegetation, while promising for coastal protection, alters sediment transport rates directly by the physical presence of the plants near the bed and indirectly from reduction in near-bed shear stresses due to attenuated wave energy. The experimental work herein focuses on the area near the deeply submerged vegetated canopy limit (current work has a ratio of mean still water depth to plant height, H/h, = 7.9) to minimize the effect on the surface waves and discern the direct impact vegetation has on sand bed morphodynamics. Experiments were conducted in the large wave tank (49-m long by 1.83-m wide by 1.22-m deep) in the Ven Te Chow Hydrosystems Laboratory at the University of Illinois in which a high reflection wave forcing was used over a uniform sand bed with a 0.25-mm median sediment diameter in which staggered and uniform arrangements of idealized vegetation (i.e., 6.35-mm diameter rigid wooden cylinders) were positioned along the bed (e.g., at predetermined sand bar troughs and over an entire sand bar). The resulting bathymetric evolution from the vegetated case experiments were compared to the base case of no vegetation using two optical methods: a high-resolution laser displacement sensor for three-dimensional surveys and digitized profiles via high-definition panoramic images of the entire test section. The experimental findings illustrate the profound

  18. Floodflow effects on riparian vegetation in Arizona

    USGS Publications Warehouse

    Phillips, J.V.; Hjalmarson, H.W.

    1994-01-01

    A relation for estimating changes in the condition of riparian vegetation as a function of stream power was developed for stream channels in central Arizona. Flood and vegetation data were collected from 13 flows at 11 sites. Stream power was computed at cross sections and plotted against the average height of vegetation for each flow. The effect of the flow - no effect, little effect, laid over, or removed - on the riparian vegetation is related to stream power and vegetation height. As vegetation height increases, the magnitude of stream power needed to affect the vegetation also increases. Stream power of about 72 Newton-meters per second per meter squared is needed to lay over 1-meter-high vegetation, and stream power of about 580 Newton-meters per second per meter squared is needed to lay over 5.5-meter-high vegetation. This relation can be used to estimate vegetation conditions at the time of peak floodflow.

  19. A garden pilot project enhances fruit and vegetable consumption among children.

    PubMed

    Heim, Stephanie; Stang, Jamie; Ireland, Marjorie

    2009-07-01

    Fruit and vegetable intake among children is inadequate. Garden-based nutrition education programs may offer a strategy for increasing fruit and vegetable intake in children. A 12-week pilot intervention was designed to promote fruit and vegetable intake among 4th to 6th grade children (n=93) attending a YMCA summer camp. Children participated in garden-based activities twice per week. Weekly educational activities included fruit and vegetable taste tests, preparation of fruit and vegetable snacks, and family newsletters sent home to parents. The pilot intervention was evaluated using a pre and post survey to determine participant satisfaction and the short-term impacts of the program. The process evaluation focused on program satisfaction, whereas the short-term impact evaluation assessed fruit and vegetable exposure, preference, self-efficacy, asking behavior, and availability of fruits and vegetables in the home. Data from the impact evaluation were compared from baseline to follow-up using McNemar's test (dichotomous variables) and Wilcoxon signed rank test (scales/continuous variables). Children reported high levels of enjoyment in the intervention activities. Most children (97.8%) enjoyed taste-testing fruits and vegetables. Children also liked preparing fruit and vegetable snacks (93.4%), working in their garden (95.6%), and learning about fruits and vegetables (91.3%). Impact data suggest that the intervention led to an increase in the number of fruits and vegetables ever eaten (P<0.001), vegetable preferences (P<0.001), and fruit and vegetable asking behavior at home (P<0.002). Garden-based nutrition education programs can increase fruit and vegetable exposure and improve predictors of fruit and vegetable intake through experiential learning activities. Participation in the "seed to table" experience of eating may help promote healthful eating behaviors among youth. Food and nutrition professionals should consider garden-based nutrition education programs

  20. Mapping and characterizing the vegetation types of the Democratic Republic of Congo using SPOT VEGETATION time series

    NASA Astrophysics Data System (ADS)

    Vancutsem, C.; Pekel, J.-F.; Evrard, C.; Malaisse, F.; Defourny, P.

    2009-02-01

    The need for quantitative and accurate information to characterize the state and evolution of vegetation types at a national scale is widely recognized. This type of information is crucial for the Democratic Republic of Congo, which contains the majority of the tropical forest cover of Central Africa and a large diversity of habitats. In spite of recent progress in earth observation capabilities, vegetation mapping and seasonality analysis in equatorial areas still represent an outstanding challenge owing to high cloud coverage and the extent and limited accessibility of the territory. On one hand, the use of coarse-resolution optical data is constrained by performance in the presence of cloud screening and by noise arising from the compositing process, which limits the spatial consistency of the composite and the temporal resolution. On the other hand, the use of high-resolution data suffers from heterogeneity of acquisition dates, images and interpretation from one scene to another. The objective of the present study was to propose and demonstrate a semi-automatic processing method for vegetation mapping and seasonality characterization based on temporal and spectral information from SPOT VEGETATION time series. A land cover map with 18 vegetation classes was produced using the proposed method that was fed by ecological knowledge gathered from botanists and reference documents. The floristic composition and physiognomy of each vegetation type are described using the Land Cover Classification System developed by the FAO. Moreover, the seasonality of each class is characterized on a monthly basis and the variation in different vegetation indicators is discussed from a phenological point of view. This mapping exercise delivers the first area estimates of seven different forest types, five different savannas characterized by specific seasonality behavior and two aquatic vegetation types. Finally, the result is compared to two recent land cover maps derived from

  1. Vegetable fuel potential. Technical report

    SciTech Connect

    Solly, R.K.

    1983-08-01

    The possible contribution to Defence fuels from vegetable sources is considered. Only two categories, ethyl alcohol from fermentation of carbohydrate material and vegetable oils directly from oil crops, can currently be produced with present technology in sufficient amounts to contribute to energy requirements. Liquid hydrocarbons from tree and shrub crops or microorganisms have not been produced in sufficient quantity to carry out even short-term engine trails. Ethyl alcohol is an effective gasoline extender for spark-ignition engines, but these are a minor part of Defence power units. Vegetable oils may be directly substituted for middle-distillate fuels, but a number of technical difficulties are outlined. Chemical reaction of the vegetable oils with ethyl alcohol produces a liquid fuel that has similar physical properties to petroleum distillate. Experimental and theoretical evidence suggests these vegetable-oil esters have better combustion properties in compression-ignition power units than petroleum distillate. Significant amounts could be produced in a strategic situation within a short lead time.

  2. Visualizing Bacillus subtilis During Vegetative Growth and Spore Formation.

    PubMed

    Wang, Xindan; Montero Llopis, Paula

    2016-01-01

    Bacillus subtilis is the most commonly used Gram-positive bacterium to study cellular processes because of its genetic tractability. In addition, during nutrient limitation, B. subtilis undergoes the development process of spore formation, which is among the simplest examples of cellular differentiation. Many aspects of these processes have benefited from fluorescence microscopy. Here, we describe basic wide-field fluorescence microscopy techniques to visualize B. subtilis during vegetative growth, and the developmental process of sporulation. PMID:27283315

  3. Incorporating geometrically complex vegetation in a computational fluid dynamic framework

    NASA Astrophysics Data System (ADS)

    Boothroyd, Richard; Hardy, Richard; Warburton, Jeff; Rosser, Nick

    2015-04-01

    Vegetation is known to have a significant influence on the hydraulic, geomorphological, and ecological functioning of river systems. Vegetation acts as a blockage to flow, thereby causing additional flow resistance and influencing flow dynamics, in particular flow conveyance. These processes need to be incorporated into flood models to improve predictions used in river management. However, the current practice in representing vegetation in hydraulic models is either through roughness parameterisation or process understanding derived experimentally from flow through highly simplified configurations of fixed, rigid cylinders. It is suggested that such simplifications inadequately describe the geometric complexity that characterises vegetation, and therefore the modelled flow dynamics may be oversimplified. This paper addresses this issue by using an approach combining field and numerical modelling techniques. Terrestrial Laser Scanning (TLS) with waveform processing has been applied to collect a sub-mm, 3-dimensional representation of Prunus laurocerasus, an invasive species to the UK that has been increasingly recorded in riparian zones. Multiple scan perspectives produce a highly detailed point cloud (>5,000,000 individual data points) which is reduced in post processing using an octree-based voxelisation technique. The method retains the geometric complexity of the vegetation by subdividing the point cloud into 0.01 m3 cubic voxels. The voxelised representation is subsequently read into a computational fluid dynamic (CFD) model using a Mass Flux Scaling Algorithm, allowing the vegetation to be directly represented in the modelling framework. Results demonstrate the development of a complex flow field around the vegetation. The downstream velocity profile is characterised by two distinct inflection points. A high velocity zone in the near-bed (plant-stem) region is apparent due to the lack of significant near-bed foliage. Above this, a zone of reduced velocity is

  4. Projected Future Vegetation Changes for the Northwest United States and Southwest Canada at a Fine Spatial Resolution Using a Dynamic Global Vegetation Model

    PubMed Central

    Shafer, Sarah L.; Bartlein, Patrick J.; Gray, Elizabeth M.; Pelltier, Richard T.

    2015-01-01

    Future climate change may significantly alter the distributions of many plant taxa. The effects of climate change may be particularly large in mountainous regions where climate can vary significantly with elevation. Understanding potential future vegetation changes in these regions requires methods that can resolve vegetation responses to climate change at fine spatial resolutions. We used LPJ, a dynamic global vegetation model, to assess potential future vegetation changes for a large topographically complex area of the northwest United States and southwest Canada (38.0–58.0°N latitude by 136.6–103.0°W longitude). LPJ is a process-based vegetation model that mechanistically simulates the effect of changing climate and atmospheric CO2 concentrations on vegetation. It was developed and has been mostly applied at spatial resolutions of 10-minutes or coarser. In this study, we used LPJ at a 30-second (~1-km) spatial resolution to simulate potential vegetation changes for 2070–2099. LPJ was run using downscaled future climate simulations from five coupled atmosphere-ocean general circulation models (CCSM3, CGCM3.1(T47), GISS-ER, MIROC3.2(medres), UKMO-HadCM3) produced using the A2 greenhouse gases emissions scenario. Under projected future climate and atmospheric CO2 concentrations, the simulated vegetation changes result in the contraction of alpine, shrub-steppe, and xeric shrub vegetation across the study area and the expansion of woodland and forest vegetation. Large areas of maritime cool forest and cold forest are simulated to persist under projected future conditions. The fine spatial-scale vegetation simulations resolve patterns of vegetation change that are not visible at coarser resolutions and these fine-scale patterns are particularly important for understanding potential future vegetation changes in topographically complex areas. PMID:26488750

  5. Projected future vegetation changes for the northwest United States and southwest Canada at a fine spatial resolution using a dynamic global vegetation model.

    USGS Publications Warehouse

    Shafer, Sarah; Bartlein, Patrick J.; Gray, Elizabeth M.; Pelltier, Richard T.

    2015-01-01

    Future climate change may significantly alter the distributions of many plant taxa. The effects of climate change may be particularly large in mountainous regions where climate can vary significantly with elevation. Understanding potential future vegetation changes in these regions requires methods that can resolve vegetation responses to climate change at fine spatial resolutions. We used LPJ, a dynamic global vegetation model, to assess potential future vegetation changes for a large topographically complex area of the northwest United States and southwest Canada (38.0–58.0°N latitude by 136.6–103.0°W longitude). LPJ is a process-based vegetation model that mechanistically simulates the effect of changing climate and atmospheric CO2 concentrations on vegetation. It was developed and has been mostly applied at spatial resolutions of 10-minutes or coarser. In this study, we used LPJ at a 30-second (~1-km) spatial resolution to simulate potential vegetation changes for 2070–2099. LPJ was run using downscaled future climate simulations from five coupled atmosphere-ocean general circulation models (CCSM3, CGCM3.1(T47), GISS-ER, MIROC3.2(medres), UKMO-HadCM3) produced using the A2 greenhouse gases emissions scenario. Under projected future climate and atmospheric CO2 concentrations, the simulated vegetation changes result in the contraction of alpine, shrub-steppe, and xeric shrub vegetation across the study area and the expansion of woodland and forest vegetation. Large areas of maritime cool forest and cold forest are simulated to persist under projected future conditions. The fine spatial-scale vegetation simulations resolve patterns of vegetation change that are not visible at coarser resolutions and these fine-scale patterns are particularly important for understanding potential future vegetation changes in topographically complex areas.

  6. Projected Future Vegetation Changes for the Northwest United States and Southwest Canada at a Fine Spatial Resolution Using a Dynamic Global Vegetation Model.

    PubMed

    Shafer, Sarah L; Bartlein, Patrick J; Gray, Elizabeth M; Pelltier, Richard T

    2015-01-01

    Future climate change may significantly alter the distributions of many plant taxa. The effects of climate change may be particularly large in mountainous regions where climate can vary significantly with elevation. Understanding potential future vegetation changes in these regions requires methods that can resolve vegetation responses to climate change at fine spatial resolutions. We used LPJ, a dynamic global vegetation model, to assess potential future vegetation changes for a large topographically complex area of the northwest United States and southwest Canada (38.0-58.0°N latitude by 136.6-103.0°W longitude). LPJ is a process-based vegetation model that mechanistically simulates the effect of changing climate and atmospheric CO2 concentrations on vegetation. It was developed and has been mostly applied at spatial resolutions of 10-minutes or coarser. In this study, we used LPJ at a 30-second (~1-km) spatial resolution to simulate potential vegetation changes for 2070-2099. LPJ was run using downscaled future climate simulations from five coupled atmosphere-ocean general circulation models (CCSM3, CGCM3.1(T47), GISS-ER, MIROC3.2(medres), UKMO-HadCM3) produced using the A2 greenhouse gases emissions scenario. Under projected future climate and atmospheric CO2 concentrations, the simulated vegetation changes result in the contraction of alpine, shrub-steppe, and xeric shrub vegetation across the study area and the expansion of woodland and forest vegetation. Large areas of maritime cool forest and cold forest are simulated to persist under projected future conditions. The fine spatial-scale vegetation simulations resolve patterns of vegetation change that are not visible at coarser resolutions and these fine-scale patterns are particularly important for understanding potential future vegetation changes in topographically complex areas. PMID:26488750

  7. Process

    SciTech Connect

    Geenen, P.V.; Bennis, J.

    1989-04-04

    A process is described for minimizing the cracking tendency and uncontrolled dimensional change, and improving the strength of a rammed plastic refractory reactor liner comprising phosphate-bonded silicon carbide or phosphate-bonded alumina. It consists of heating the reactor liner placed or mounted in a reactor, prior to its first use, from ambient temperature up to a temperature of from about 490/sup 0/C to about 510/sup 0/C, the heating being carried out by heating the liner at a rate to produce a temperature increase of the liner not greater than about 6/sup 0/C per hour.

  8. Characterization of forest vegetation-climate feedback regimes by satellite remote sensing imagery

    NASA Astrophysics Data System (ADS)

    Zoran, Maria

    Vegetation and climate interact through a series of complex feedbacks, which are not very well understood.The patterns of forest vegetation are largely determined by temperature, precipitation, solar irradiance, soil conditions and CO2 concentration. Vegetation impacts climate directly through moisture, energy, and momentum exchanges with the atmosphere and indirectly through biogeochemical processes that alter atmospheric CO2 concentration. Changes in forest vegetation landuse-landcover alter the surface albedo and radiation fluxes, leading to a local temperature change and eventually a vegetation response. This albedo (energy) feedback is particularly important when forests mask snow cover. Forest vegetation-climate feedback regimes are designated based on the temporal correlations between the vegetation and and the surface temperature and precipitation. The different feedback regimes are linked to the relative importance of vegetation and soil moisture in determining land-atmosphere interactions. The spatio-temporal dynamics are assessed in terms of the NDVI-surface temperature correlations.Observed vegetation feedbacks on temperature and precipitation are assessed based on Landsat TM, ETM, MODIS and IKONOS satellite data across the forested areas in North/Eastern part of Bucharest town, Romania for a period of 1984 -2007 period. The computed feedback parameters can be used to evaluate vegetation-climate interactions simulated by models with dynamic vegetation. Specific aim of this paper is to assess the forest vegetationclimate feedbacks on forest ecosystem and its biodiversity as well as on adjacent environment areas and to provide early warning strategies on the remote sensing spectral information basis.

  9. Shortwave infrared detection of vegetation

    NASA Astrophysics Data System (ADS)

    Goward, Samuel N.

    Shortwave infrared sensors were included on Thematic Mapper to observe vegetation reflected radiance patterns that are related to leaf water content. However, there was some uncertainty whether these measurements would increase the information content of multispectral measurements beyond that provided by visible and near infrared measurements. Analysis of field measurements for corn and soybeans observed throughout the growing season shows that shortwave infrared measurements enhance discrimination between these species, particularly in mid-season. Modeling the canopy reflectances shows that differential leaf absorptance can produce the observed pattern. Analysis of coincident aerial photography suggests that within canopy shadowing is also important. Too few studies of leaf optical properties have been conducted to permit generalization of the results to other vegetation species but the results do show that shortwave infrared measurements contribute new information about vegetation not previously available in visible and near infrared measurements.

  10. Assessing global vegetation activity using spatio-temporal Bayesian modelling

    NASA Astrophysics Data System (ADS)

    Mulder, Vera L.; van Eck, Christel M.; Friedlingstein, Pierre; Regnier, Pierre A. G.

    2016-04-01

    This work demonstrates the potential of modelling vegetation activity using a hierarchical Bayesian spatio-temporal model. This approach allows modelling changes in vegetation and climate simultaneous in space and time. Changes of vegetation activity such as phenology are modelled as a dynamic process depending on climate variability in both space and time. Additionally, differences in observed vegetation status can be contributed to other abiotic ecosystem properties, e.g. soil and terrain properties. Although these properties do not change in time, they do change in space and may provide valuable information in addition to the climate dynamics. The spatio-temporal Bayesian models were calibrated at a regional scale because the local trends in space and time can be better captured by the model. The regional subsets were defined according to the SREX segmentation, as defined by the IPCC. Each region is considered being relatively homogeneous in terms of large-scale climate and biomes, still capturing small-scale (grid-cell level) variability. Modelling within these regions is hence expected to be less uncertain due to the absence of these large-scale patterns, compared to a global approach. This overall modelling approach allows the comparison of model behavior for the different regions and may provide insights on the main dynamic processes driving the interaction between vegetation and climate within different regions. The data employed in this study encompasses the global datasets for soil properties (SoilGrids), terrain properties (Global Relief Model based on SRTM DEM and ETOPO), monthly time series of satellite-derived vegetation indices (GIMMS NDVI3g) and climate variables (Princeton Meteorological Forcing Dataset). The findings proved the potential of a spatio-temporal Bayesian modelling approach for assessing vegetation dynamics, at a regional scale. The observed interrelationships of the employed data and the different spatial and temporal trends support

  11. Monitoring vegetation water uptake in a semiarid riparian corridor

    NASA Astrophysics Data System (ADS)

    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.

  12. Sediment transport and shear stress partitioning in a vegetated flow

    NASA Astrophysics Data System (ADS)

    Le Bouteiller, Caroline; Venditti, J. G.

    2015-04-01

    Vegetation is a common feature in natural coastal and riverine water ways, interacting with both the water flow and sediment transport. However, the physical processes governing these interactions are still poorly understood, which makes it difficult to predict sediment transport and morphodynamics in a vegetated environment. We performed a simple experiment to study how sediment transport responds to the presence of flexible, single-blade vegetation, and how this response is influenced by the vegetation density. We found that the skin friction and sediment transport are reduced in a plant patch, and that this effect is larger for denser vegetation. We then evaluated several methods to calculate the skin friction in a vegetated flow, which is the key to sediment transport prediction. Among these, the inversion of bed load transport formulas and the Einstein and Banks (1950) methods appeared to produce the most reasonable values of the skin friction. Finally, we suggest using the parameter α, which is the ratio of the skin friction computed by these methods to the total bed shear stress, to make more realistic sediment transport predictions in morphodynamic models.

  13. Aspects of Radiation Budget, Subsurface Lateral Moisture Exchange, and Vegetation Function in Areas of Complex Topography.

    NASA Astrophysics Data System (ADS)

    Ivanov, V. Y.; Bras, R. L.; Istanbulluoglu, E.; Vivoni, E. R.

    2004-12-01

    There is evidence that topography strongly affects the state, function, and distribution of vegetation by controlling incoming solar radiation and lateral redistribution of soil moisture. However, numerical experiments studying the effects that a topography can have on vegetation have oversimplified the treatment of topography and/or the representation of vegetation. We investigate the control of topography on vegetation state and stress via detailed modeling of radiation and soil moisture budgets across the varied terrain of a watershed. A detailed vegetation-hydrology model parameterizes the processes of canopy radiative transfer and rainfall interception and couples the processes of infiltration and evapotranspiration to photosynthesis via moisture uptake through a root systems with varied profiles. The model is applied on a continuous basis to synthetic watersheds of topography dominated by either convex or concave hillslopes. The numerical analysis is carried out for several plant functional types and soils. Inferences from the spatially-distributed dynamics are used to examine topographic niches favorable to vegetation.

  14. Reactive glass and vegetation patterns.

    PubMed

    Shnerb, N M; Sarah, P; Lavee, H; Solomon, S

    2003-01-24

    The formation of vegetation patterns in the arid and the semiarid climatic zones is studied. Threshold for the biomass of the perennial flora is shown to be a relevant factor, leading to a frozen disordered pattern in the arid zone. In this "glassy" state, vegetation appears as singular plant spots separated by irregular distances, and an indirect repulsive interaction among shrubs is induced by the competition for water. At higher precipitation rates, the diminishing of hydrological losses in the presence of flora becomes important and yields spatial attraction and clustering of biomass. Turing patterns with characteristic length scale emerge from the disordered structure due to this positive-feedback instability. PMID:12570527

  15. The contribution of vegetation to riverbed morphology (Invited)

    NASA Astrophysics Data System (ADS)

    Bertoldi, W.; Gurnell, A. M.

    2010-12-01

    The occurrence, form and species composition of riparian and aquatic vegetation are all strongly affected by the flow energy regime, sediment calibre and dimensions of river systems. In this paper, we build on field examples to conceptualise how interactions between vegetation and fluvial processes may affect river form across a gradient of river types from high-energy gravel-bed braided rivers to lowland single-thread silt-bed rivers. We explore how different vegetation types (e.g. riparian trees, shrubs, emergent macrophytes), and in some cases particular plant species, can produce similar impacts on the bed topography of rivers of different size, because of their effect on sediment transport flux and sediment cohesion, and a resultant positive feedback that increases the bar or bank height. We illustrate these concepts using two case studies representing extremes of river size and energy. Field and remotely sensed data are used to identify and quantify impacts of vegetation density on the bed morphology of the >1km wide, gravel-bed, braided Tagliamento River (Italy). Analysis of airborne LiDAR data is used to compute a highly detailed digital elevation model, along with data on tree height and density. The comparison between reaches with different tree height and density clearly shows the active role of vegetation in determining river pattern and form, with tree growth rate being the main parameter determining the vegetation effect. Analysis of field measurements of flow patterns and mechanical properties of emergent aquatic macrophytes on the <10m wide, silt-bed, single-thread River Blackwater (England) illustrate the close correspondence of the bed topography with vegetation structures, with position along an energy gradient dictating changes in the structure of the vegetation-bed morphology interaction.

  16. Interactions among hydrogeomorphology, vegetation, and nutrient biogeochemistry in floodplain ecosystems

    USGS Publications Warehouse

    Noe, G.B.

    2013-01-01

    Hydrogeomorphic, vegetative, and biogeochemical processes interact in floodplains resulting in great complexity that provides opportunities to better understand linkages among physical and biological processes in ecosystems. Floodplains and their associated river systems are structured by four-dimensional gradients of hydrogeomorphology: longitudinal, lateral, vertical, and temporal components. These four dimensions create dynamic hydrologic and geomorphologic mosaics that have a large imprint on the vegetation and nutrient biogeochemistry of floodplains. Plant physiology, population dynamics, community structure, and productivity are all very responsive to floodplain hydrogeomorphology. The strength of this relationship between vegetation and hydrogeomorphology is evident in the use of vegetation as an indicator of hydrogeomorphic processes. However, vegetation also influences hydrogeomorphology by modifying hydraulics and sediment entrainment and deposition that typically stabilize geomorphic patterns. Nitrogen and phosphorus biogeochemistry commonly influence plant productivity and community composition, although productivity is not limited by nutrient availability in all floodplains. Conversely, vegetation influences nutrient biogeochemistry through direct uptake and storage as well as production of organic matter that regulates microbial biogeochemical processes. The biogeochemistries of nitrogen and phosphorus cycling are very sensitive to spatial and temporal variation in hydrogeomorphology, in particular floodplain wetness and sedimentation. The least-studied interaction is the direct effect of biogeochemistry on hydrogeomorphology, but the control of nutrient availability over organic matter decomposition and thus soil permeability and elevation is likely important. Biogeochemistry also has the more documented but indirect control of hydrogeomorphology through regulation of plant biomass. In summary, the defining characteristics of floodplain ecosystems

  17. Evolution of vegetation activity on well-vegetated and degraded areas in the central Spanish Pyrenees, using multitemporal Landsat imagery

    NASA Astrophysics Data System (ADS)

    Alatorre, Luis Carlos; Beguería, Santaigo; Lana-Renault, Noemí

    2010-05-01

    The temporal evolution of vegetation activity on various land cover classes in the Spanish Pyrenees was analyzed. The study area is located at 620-2,149 m altitude approximately 23 km north of the Barasona Reservoir, is an integrated badlands landscape orientated northwest-southeast and developed on Eocene marls. The objectives of this study were: i) to obtain time series of vegetation activity during two contrasting periods of the growth cycle (early spring and the end of summer) for various land cover classes, including both well-vegetated and degraded areas (badlands and erosion risk areas); ii) to determine the extent by which climate controls vegetation activity in the various land cover classes, and to define temporal trends; and, iii) to analyze the spatial distribution of trends in vegetation activity on erosion risk areas, as indicators of recovery and degradation, and to quantify the effects of various topographical factors on such trends. Two time series of the normalized difference vegetation index (NDVI) were used, corresponding to March (early spring) and August (the end of summer). The series were generated from Landsat TM and Landsat ETM+ images for the period 1984-2007. An increase in the NDVI in March was found for vegetated areas, and the opposite trend was found in both March and August for degraded areas (badlands and erosion risk areas). The rise in minimum temperature during the study period appears to be the most important factor explaining the increased NDVI in the vegetated areas. In degraded areas, no climatic or topographic variable was associated with the negative trend in the NDVI, which may be related to erosion processes taking place in these regions.

  18. Analysis of the dynamics of African vegetation using the normalized difference vegetation index

    NASA Technical Reports Server (NTRS)

    Townshend, J. R. G.; Justice, C. O.

    1986-01-01

    Images at a resolution of 8 km are currently being generated for the whole of Africa, displaying the normalized difference vegetation index (NDVI). These images have undergone a process of temporal compositing to reduce the effects of cloud cover and atmospheric variation. When the NDVI is plotted against time, different cover types are shown to have characteristic profiles corresponding closely with their phenology. The resultant pattern of NDVI values displayed on the images is analyzed in terms of the cover types present and local variations in rainfall. Comparison between images for 1983 and 1984 overall showed considerable similarities, but significant differences were observed in the northward extent of the greening wave in the Sahel, the greening up of the Kalahari Desert and East African communities. It is concluded that vegetation monitoring using NDVI images needs to be associated with scene stratification according to cover type.

  19. 'Vegetable' substitutes for diesel fuel

    SciTech Connect

    Not Available

    1981-07-22

    Research programs in the US, Brazil, South Africa and the Philippines on efforts to find a vegetable oil substitute for diesel fuel are reported. A narrowing price gap with diesel fuel and a favourable energy balance improve the prospects for such fuels. Much of the current work is centered on blends, rather than the use of the pure oil.

  20. IMPACT OF OZONE ON VEGETATION

    EPA Science Inventory

    Visible injury on vegetation is one of the earliest and most obvious manifestations of ozone injury. However, ozone effects are not limited to visible injury; impacts range from reduced plant growth, decreased yield, changes in crop quality and alterations in susceptibility to ab...

  1. BUFFERS AND VEGETATIVE FILTER STRIPS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Buffers and filter strips are areas of permanent vegetation located within and between agricultural fields and the water courses to which they drain. These buffers are intended to intercept and slow runoff thereby providing water quality benefits. In addition, in many settings they are intended to...

  2. Spatial vegetation patterns and desertification

    NASA Astrophysics Data System (ADS)

    Rietkerk, M.; Kéfi, S.

    2009-04-01

    Arid ecosystems are amongst the most sensitive ecosystems to human pressure and climate change, and are liable to undergo desertification. This is a main concern because this may occur abruptly and irreversibly, with concomitant losses of ecological and economic resources. Such ecosystem shifts have been theoretically attributed to positive feedback and alternative stable ecosystem states. However, verifications and predictive power with respect to such ecosystem dynamics are lacking for spatially extensive ecosystems. Therefore, management and recovery strategies against desertification for arid ecosystems are difficult to achieve. Theoretical models predict that so-called regular vegetation patterns observed in large areas in arid ecosystems world-wide are a result of spatial self-organization, and the shapes of the patterns are associated with approaching desertification thresholds. Also, patch-size distribution of the vegetation in various arid ecosystems follows a power law, and consistent deviations from power laws occur if grazing pressure is high. Model analysis suggests that such deviations from power laws may be a warning signal for the onset of desertification, independent of the vegetation cover. So, spatial patterns of vegetation, not cover, can be used to assess the vulnerability of arid ecosystems to increased human pressure or ongoing climate change. Common ecological mechanisms that account for these patterns are scale-dependent feedback and local facilitation. Our results are relevant to identify areas that are vulnerable to desertification in the face of increased human pressure and ongoing global climate change, as well as for the restoration of areas that are already degraded.

  3. Vegetable Crop Pests. MEP 311.

    ERIC Educational Resources Information Center

    Kantzes, James G.; And Others

    As part of a cooperative extension service series by the University of Maryland, this publication introduces the identification and control of common agricultural pests of vegetable crops. The first of the five sections defines "pest" and "weed" and generally introduces different kinds of pests in the categories of insects, weeds, and diseases.…

  4. Grafting effects on vegetable quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vegetable grafting began in the 1920s to control soil-borne disease. It is now a common practice in Asia, parts of Europe, and the Middle East. In Japan and Korea most of the cucurbits and tomatoes (Lycopersicon esculentum Mill.) grown are grafted. This practice is rare in the U.S. and there have...

  5. GLOBAL ORGANIC EMISSIONS FROM VEGETATION

    EPA Science Inventory

    The book chapter discusses several aspects of biogenic volatile organic compound (BVOC) emissions from vegetation. It begins with a section on emission measurements that includes a brief history of enclosure and above-canopy flux measurements as well as a discussion of existing d...

  6. Vegetable production after heavy rains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It is not clear if extraordinary precipitation stored in the soil was able to support vegetable crops planted after rains events returned to normal levels. Cucumber and sweet corn were established from seed and non-pungent jalapeno peppers were established from 8-week old transplants on beds. Half...

  7. Classification of vegetation types in military region

    NASA Astrophysics Data System (ADS)

    Gonçalves, Miguel; Silva, Jose Silvestre; Bioucas-Dias, Jose

    2015-10-01

    In decision-making process regarding planning and execution of military operations, the terrain is a determining factor. Aerial photographs are a source of vital information for the success of an operation in hostile region, namely when the cartographic information behind enemy lines is scarce or non-existent. The objective of present work is the development of a tool capable of processing aerial photos. The methodology implemented starts with feature extraction, followed by the application of an automatic selector of features. The next step, using the k-fold cross validation technique, estimates the input parameters for the following classifiers: Sparse Multinomial Logist Regression (SMLR), K Nearest Neighbor (KNN), Linear Classifier using Principal Component Expansion on the Joint Data (PCLDC) and Multi-Class Support Vector Machine (MSVM). These classifiers were used in two different studies with distinct objectives: discrimination of vegetation's density and identification of vegetation's main components. It was found that the best classifier on the first approach is the Sparse Logistic Multinomial Regression (SMLR). On the second approach, the implemented methodology applied to high resolution images showed that the better performance was achieved by KNN classifier and PCLDC. Comparing the two approaches there is a multiscale issue, in which for different resolutions, the best solution to the problem requires different classifiers and the extraction of different features.

  8. Serving vegetables first: A strategy to increase vegetable consumption in elementary school cafeterias.

    PubMed

    Elsbernd, S L; Reicks, M M; Mann, T L; Redden, J P; Mykerezi, E; Vickers, Z M

    2016-01-01

    Vegetable consumption in the United States is low despite the wealth of evidence that vegetables play an important role in reducing risk of various chronic diseases. Because eating patterns developed in childhood continue through adulthood, we need to form healthy eating habits in children. The objective of this study was to determine if offering vegetables before other meal components would increase the overall consumption of vegetables at school lunch. We served kindergarten through fifth-grade students a small portion (26-33 g) of a raw vegetable (red and yellow bell peppers) while they waited in line to receive the rest of their lunch meal. They then had the options to take more of the bell peppers, a different vegetable, or no vegetable from the lunch line. We measured the amount of each vegetable consumed by each child. Serving vegetables first greatly increased the number of students eating vegetables. On intervention days most of the vegetables consumed came from the vegetables-first portions. Total vegetable intake per student eating lunch was low because most students chose to not eat vegetables, but the intervention significantly increased this value. Serving vegetables first is a viable strategy to increase vegetable consumption in elementary schools. Long-term implementation of this strategy may have an important impact on healthy eating habits, vegetable consumption, and the health consequences of vegetable intake. PMID:26344812

  9. Dynamical effects of vegetation on the 2003 summer heat waves

    NASA Astrophysics Data System (ADS)

    Stéfanon, M.

    2012-04-01

    Dynamical effects of vegetation on the 2003 summer heat waves Marc Stéfanon(1), Philippe Drobinski(1), Fabio D'Andrea(1), Nathalie de Noblet(2) (1) IPSL/LMD, France; (2) IPSL/LSCE, France The land surface model (LSM) in regional climate models (RCMs) plays a key role in energy and water exchanges between land and atmosphere. The vegetation can affect these exchanges through physical, biophysical and bio-geophysical mechanisms. It participates to evapo-transpiration process which determines the partitioning of net radiation between sensible and latent heat flux, through water evaporation from soil throughout the entire root system. For seasonal timescale leaf cover change induced leaf-area index (LAI) and albedo changes, impacting the Earth's radiative balance. In addition, atmospheric chemistry and carbon concentration has a direct effect on plant stomatal structure, the main exchange interface with the atmosphere. Therefore the surface energy balance is intimately linked to the carbon cycle and vegetation conditions and an accurate representation of the Earth's surface is required to improve the performance of RCMs. It is even more crucial for extreme events as heat waves and droughts which display highly nonlinear behaviour. If triggering of heat waves is determined by the large scale, local coupled processes over land can amplify or inhibit heat trough several feedback mechanism. One set of two simulation has been conducted with WRF, using different LSMs. They aim to study drought and vegetation effect on the dynamical and hydrological processes controlling the occurrence and life cycle of heat waves In the MORCE plateform, the dynamical global vegetation model (DGVM) ORCHIDEE is implemented in the atmospheric module WRF. ORCHIDEE is based on three different modules. The first module, called SECHIBA, describes the fast processes such as exchanges of energy and water between the atmosphere and the biosphere, and the soil water budget. The phenology and carbon

  10. Geomorphological controls on coastal vegetation at the Virginia Coast Reserve

    NASA Astrophysics Data System (ADS)

    Hayden, Bruce P.; Santos, Marcio C. F. V.; Shao, Guofan; Kochel, R. Craig

    1995-09-01

    The establishment and succession of vegetation on migrating, low-profile barrier islands is greatly affected by the physical hydrogeomorphological processes that regulate island topography, saline and fresh groundwater table surfaces. Apart from the physical destruction of plants by overwash processes, fluctuations in water table elevations and variations in groundwater salinity, both spatially and temporally, also appear to have significant impact on the nature and distribution of vegetation on these islands. Species composition, community structure and biodiversity on the Virginia barrier islands are controlled by the same processes that give rise to landforms and maintain their form. These processes include marine water inundations, groundwater salinity variations and changes in depth to the fresh-water table. Land surface elevation, landform morphology and position on the barrier island determine exposure to high tides, storm surges, sand burial, and the extent of the fresh-water reserves. In this article, the underpinnings of a Long-term Ecological Research Program in which 25 geologists, geomorphologists, climatologists, and ecologists have a common research plan is presented and several examples of the product of this research partnership dealing with geomorphological and hydrologic controls on vegetation dynamics are detailed. Among the aspects of ecological dynamics examined in terms of geomorphological processes are vegetation zonation, succession, disturbance, and ecosystem state change.

  11. Slow recovery in desert perennial vegetation following prolonged human disturbance

    USGS Publications Warehouse

    Guo, Q.

    2004-01-01

    Questions: How long may it take for desert perennial vegetation to recover from prolonged human disturbance and how do different plant community variables (i.e. diversity, density and cover) change during the recovery process? Location: Sonoran Desert, Arizona, USA. Methods: Since protection from grazing from 1907 onwards, plant diversity, density and cover of perennial species were monitored intermittently on ten 10 m x 10 m permanent plots on Tumamoc Hill, Tucson, Arizona, USA. Results: The study shows an exceptionally slow recovery of perennial vegetation from prolonged heavy grazing and other human impacts. Since protection, overall species richness and habitat heterogeneity at the study site continued to increase until the 1960s when diversity, density and cover had been stabilized. During the same period, overall plant density and cover also increased. Species turnover increased gradually with time but no significant relation between any of the three community variables and precipitation or Palmer Drought Severity Index (PDSI) was detected. Conclusions: It took more than 50 yr for the perennial vegetation to recover from prolonged human disturbance. The increases in plant species richness, density, and cover of the perennial vegetation were mostly due to the increase of herbaceous species, especially palatable species. The lack of a clear relationship between environment (e.g. precipitation) and community variables suggests that site history and plant life history must be taken into account in examining the nature of vegetation recovery processes after disturbance.

  12. Osmotic dehydration of fruits and vegetables: a review.

    PubMed

    Yadav, Ashok Kumar; Singh, Satya Vir

    2014-09-01

    The main cause of perishability of fruits and vegetables are their high water content. To increase the shelf life of these fruits and vegetables many methods or combination of methods had been tried. Osmotic dehydration is one of the best and suitable method to increase the shelf life of fruits and vegetables. This process is preferred over others due to their vitamin and minerals, color, flavor and taste retention property. In this review different methods, treatments, optimization and effects of osmotic dehydration have been reviewed. Studied showed that combination of different osmotic agents were more effective than sucrose alone due to combination of properties of solutes. During the experiments it was found that optimum osmosis was found at approximately 40 °C, 40 °B of osmotic agent and in near about 132 min. Pretreatments also leads to increase the osmotic process in fruits and vegetables. Mass transfer kinetics study is an important parameter to study osmosis. Solids diffusivity were found in wide range (5.09-32.77 kl/mol) studied by Fick's laws of diffusion. These values vary depending upon types of fruits and vegetables and osmotic agents. PMID:25190823

  13. Steady nonuniform shallow flow within emergent vegetation

    NASA Astrophysics Data System (ADS)

    Wang, Wei-Jie; Huai, Wen-Xin; Thompson, Sally; Katul, Gabriel G.

    2015-12-01

    Surface flow redistribution on flat ground from crusted bare soil to vegetated patches following intense rainfall events elevates plant available water above that provided by rainfall. The significance of this surface water redistribution to sustaining vegetation in arid and semiarid regions is undisputed. What is disputed is the quantity and spatial distribution of the redistributed water. In ecohydrological models, such nonuniform flows are described using the Saint-Venant equation (SVE) subject to a Manning roughness coefficient closure. To explore these assumptions in the most idealized setting, flume experiments were conducted using rigid cylinders representing rigid vegetation with varying density. Flow was induced along the streamwise x direction by adjusting the free water surface height H(x) between the upstream and downstream boundaries mimicking the nonuniformity encountered in nature. In natural settings, such H(x) variations arise due to contrasts in infiltration capacity and ponded depths during storms. The measured H(x) values in the flume were interpreted using the SVE augmented with progressively elaborate approximations to the roughness representation. The simplest approximation employs a friction factor derived from a drag coefficient (Cd) for isolated cylinders in a locally (but not globally) uniform flow and upscaled using the rod density that was varied across experiments. Comparison between measured and modeled H(x) suggested that such a "naive" approach overpredicts H(x). Blockage was then incorporated into the SVE model calculations but resulted in underestimation of H(x). Biases in modeled H(x) suggest that Cd must be varying in x beyond what a local or bulk Reynolds number predicts. Inferred Cd(x) from the flume experiments exhibited a near-parabolic shape most peaked in the densest canopy cases. The outcome of such Cd(x) variations is then summarized in a bulk resistance formulation that may be beneficial to modeling runon

  14. MODIS Vegetative Cover Conversion and Vegetation Continuous Fields

    NASA Astrophysics Data System (ADS)

    Carroll, Mark; Townshend, John; Hansen, Matthew; DiMiceli, Charlene; Sohlberg, Robert; Wurster, Karl

    Land cover change occurs at various spatial and temporal scales. For example, large-scale mechanical removal of forests for agro-industrial activities contrasts with the small-scale clearing of subsistence farmers. Such dynamics vary in spatial extent and rate of land conversion. Such changes are attributable to both natural and anthropogenic factors. For example, lightning- or human-ignited fires burn millions of acres of land surface each year. Further, land cover conversion requires ­contrasting with the land cover modification. In the first instance, the dynamic represents extensive categorical change between two land cover types. Land cover modification mechanisms such as selective logging and woody encroachment depict changes within a given land cover type rather than a conversion from one land cover type to another. This chapter describes the production of two standard MODIS land products used to document changes in global land cover. The Vegetative Cover Conversion (VCC) product is designed primarily to serve as a global alarm for areas where land cover change occurs rapidly (Zhan et al. 2000). The Vegetation Continuous Fields (VCF) product is designed to continuously ­represent ground cover as a proportion of basic vegetation traits. Terra's launch in December 1999 afforded a new opportunity to observe the entire Earth every 1.2 days at 250-m spatial resolution. The MODIS instrument's appropriate spatial and ­temporal resolutions provide the opportunity to substantially improve the characterization of the land surface and changes occurring thereupon (Townshend et al. 1991).

  15. An overview of research on the beneficial effects of vegetation in contaminated soil.

    PubMed

    Erickson, L E

    1997-11-21

    Vegetation can enhance in situ bioremediation processes in many applications. Microbial transformations occur in soil and water external to plant roots. Organic contaminants also enter vegetation and are transformed within plants. Research progress is reviewed with emphasis on recent experimental results and mathematical models of contaminant fate in systems where vegetation is present. Plant evapotranspiration provides a solar driven pump-and-treat system which moves contaminants to the rhizosphere and helps to contain them on site. Significant savings have been reported at several field sites where vegetation has been utilized. PMID:9472312

  16. Near ground level sensing for spatial analysis of vegetation

    NASA Technical Reports Server (NTRS)

    Sauer, Tom; Rasure, John; Gage, Charlie

    1991-01-01

    Measured changes in vegetation indicate the dynamics of ecological processes and can identify the impacts from disturbances. Traditional methods of vegetation analysis tend to be slow because they are labor intensive; as a result, these methods are often confined to small local area measurements. Scientists need new algorithms and instruments that will allow them to efficiently study environmental dynamics across a range of different spatial scales. A new methodology that addresses this problem is presented. This methodology includes the acquisition, processing, and presentation of near ground level image data and its corresponding spatial characteristics. The systematic approach taken encompasses a feature extraction process, a supervised and unsupervised classification process, and a region labeling process yielding spatial information.

  17. CHARACTERIZATION OF RIPARIAN VEGETATION IN OFF-CHANNEL HABITATS AND RELATIONSHIPS WITH ANNUAL FLOODING PATTERNS, UPPER MAIN STEM, WILLAMETTE RIVER, OREGON

    EPA Science Inventory

    Hydrogeomorphic processes drive riparian vegetation establishment, growth, and longevity. The stage of vegetation development (e.g. age, composition, height, density) affects its degree of functionality with respect to hydrology, nutrient cycling, and terrestrial and aquatic hab...

  18. TREATMENT OF EFFLUENT WATERS FROM VEGETABLE OIL REFINING

    EPA Science Inventory

    A detailed investigation was done to characterize the wastewater from a vegetable oil refinery. A calcium chloride chemical treatment was installed which resulted in a net decrease in waste load of 71 percent from .0135 lb BOD5 per pound oil processed to .0039 lb BOD5 per pound o...

  19. Modified atmosphere packaging for fresh-cut fruits and vegetables

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The latest development in and different aspects of modified atmosphere packaging for fresh-cut fruits and vegetables are reviewed in the book. This book provides all readers, including fresh-cut academic researchers, fresh-cut R&D personnel, and fresh-cut processing engineers, with unique, essential...

  20. Effect of ionizing radiation on furan formation in fresh-cut fruits and vegetables

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Furan, a possible carcinogen, is commonly induced by thermal processing in a wide variety of foods. The possible formation of furan from fresh-cut fruits and vegetables due to irradiation was studied. Nineteen fresh-cut fruits and vegetables were irradiated to 5 kGy gamma rays at 4C. Furan was an...

  1. Abnormal Functional MRI BOLD Contrast in the Vegetative State after Severe Traumatic Brain Injury

    ERIC Educational Resources Information Center

    Heelmann, Volker

    2010-01-01

    For the rehabilitation process, the treatment of patients surviving brain injury in a vegetative state is still a serious challenge. The aim of this study was to investigate patients exhibiting severely disturbed consciousness using functional magnetic resonance imaging. Five cases of posttraumatic vegetative state and one with minimal…

  2. 75 FR 43141 - United States Standards for Grades of Frozen Vegetables

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-23

    ...The Agricultural Marketing Service (AMS), prior to undertaking research and other work associated with revising official grade standards, is soliciting comments on the possible revisions to eighteen U.S. grade standards for frozen vegetables issued on or before July 22, 1985. AMS annually reviews its processed fruit and vegetable grade standards for suitability and has identified eighteen......

  3. Vegetation hydrological behaviour along a Mediterranean pluviometric gradient.

    NASA Astrophysics Data System (ADS)

    Damian Ruiz Sinoga, Jose; Gabarron Galeote, Miguel Angel; Francisco Martinez Murillo, Juan

    2010-05-01

    A pluviometric gradient was defined in South of Spain with a great decreased of rainfall from Western (1100 mm y-1) to Eastern (240 mm y-1), related with changes in vegetation and soil hydrological resources. This study was carried out in five hillslopes under different pluviometric conditions and their aims were to analyze i) the differences in the moisten and dry up soil processes of the hillslopes, ii) the variability of available water along the gradient since 2002 to 2006, iii) their key factors and the influence on vegetal cover. Several soil properties have been analysed. Results showed that clay content had a great influence in the topsoil available water for plants, which did not decrease in the drier field sites, where the amount of days with hydric deficit was lower. Have been found important differences in the soil hydrological behaviour of the humid and arid hillslopes, caused by the stronger relations between soil moisture, available water and vegetation in the more humid hillslopes, where existed a feed-back between these properties; these relations are weaker in the arid field sites. This feed-back can be explained by high consumption of water that vegetable species need to survive in the humid hillslopes, which cause a strong dependence water-vegetation, a different kind of vegetation cover depending of the rainfall and a quick consumption of this, once it is in the soil. On the contrary, in the arid hillslopes, vegetable species are better adapted to shortage of soil water content, so they are more independent of the amount of rainfall, the soil moisture and the available water, that remains more time in the soil.

  4. Importance of vegetation for manganese cycling in temperate forested watersheds

    NASA Astrophysics Data System (ADS)

    Herndon, Elizabeth M.; Jin, Lixin; Andrews, Danielle M.; Eissenstat, David M.; Brantley, Susan L.

    2015-02-01

    Many surface soils are enriched in metals due to anthropogenic atmospheric inputs. To predict the persistence of these contaminants in soils, factors that impact rates of metal removal from soils into streams must be understood. Experiments at containerized seedling (mesocosm), pedon, and catchment scales were used to investigate the influence of vegetation on manganese (Mn) transport at the Susquehanna/Shale Hills Critical Zone Observatory (SSHCZO) in Pennsylvania, USA, where past atmospheric inputs from industrial sources have enriched Mn in surface soils. Large quantities of Mn that were leached from soil components into solution were taken up by vegetation; as a result, only relatively small quantities of Mn were removed from soil into effluent and streams. Manganese uptake into vegetation exceeded Mn losses in soil leachate by 20-200X at all scales, and net Mn loss from soils decreased in the presence of vegetation due to uptake into plant tissues. The majority of Mn taken up by forest vegetation at SSHCZO each year was returned to the soil in leaf litter and consequently immobilized as Mn oxides that formed during litter decomposition. Thus, plant uptake of Mn combined with rapid oxidation of Mn during litter decomposition contribute to long-term retention. Current release rates of soluble Mn from SSHCZO soils were similar to release rates from the larger Susquehanna River Basin, indicating that the processes observed at SSHCZO may be widespread across the region. Indeed, although atmospheric deposition of Mn has declined, surface soils at SSHCZO and throughout the eastern United States remain enriched in Mn. If recycling through vegetation can attenuate the removal of Mn from soils, as observed in this study, then Mn concentrations in soils and river waters will likely decrease slowly over time following watershed contamination. Understanding the role of vegetation in regulating metal transport is important for evaluating the long-term effects of historical

  5. Measurement of soil hydraulic conductivity in relation with vegetation

    NASA Astrophysics Data System (ADS)

    Chen, Xi; Cheng, Qinbo

    2010-05-01

    Hydraulic conductivity is a key parameter which influences hydrological processes of infiltration, surface and subsurface runoff. Vegetation alters surface characteristics (e.g., surface roughness, litter absorption) or subsurface characteristics (e.g. hydraulic conductivity). Field infiltration experiment of a single ring permeameter is widely used for measuring soil hydraulic conductivity. Measurement equipment is a simple single-ring falling head permeameter which consists of a hollow cylinder that is simply inserted into the top soil. An optimization method on the basis of objective of minimum error between the measured and simulated water depths in the single-ring is developed for determination of the soil hydraulic parameters. Using the single ring permeameter, we measured saturated hydraulic conductivities (Ks) of the red loam soil with and without vegetation covers on five hillslopes at Taoyuan Agro-Ecology Experimental Station, Hunan Province of China. For the measurement plots without vegetation roots, Ks value of the soil at 25cm depth is much smaller than that of surface soil (1.52×10-4 vs. 1.10×10-5 m/s). For the measurement plots with vegetation cover, plant roots significantly increase Ks of the lower layer soil but this increase is not significant for the shallow soil. Moreover, influences of vegetation root on Ks depend on vegetation species and ages. Ks value of the Camellia is about three times larger than that of seeding of Camphor (2.62×10-4 vs. 9.82×10-5 m/s). Ks value of the matured Camellia is 2.72×10-4 m/s while Ks value of the young Camellia is only 2.17×10-4 m/s. Key words: single ring permeameter; soil hydraulic conductivity; vegetation

  6. Vegetation Health and Productivity Indicators for Sustained National Climate Assessments

    NASA Astrophysics Data System (ADS)

    Jones, M. O.; Running, S. W.

    2014-12-01

    The National Climate Assessment process is developing a system of physical, ecological, and societal indicators that communicate key aspects of the physical climate, climate impacts, vulnerabilities, and preparedness for the purpose of informing both decision makers and the public. Implementing a 14 year record of Gross and Net Primary Productivity (GPP/NPP) derived from the NASA EOS MODIS satellite sensor we demonstrate how these products can serve as Ecosystem Productivity and Vegetation Health National Climate Indicators for implementation in sustained National Climate Assessments. The NPP product combines MODIS vegetation data with daily global meteorology to calculate annual growth of all plant material at 1 sq. km resolution. NPP anomalies identify regions with above or below average plant growth that may result from climate fluctuations and can inform carbon source/sink dynamics, agricultural and forestry yield measures, and response to wildfire or drought conditions. The GPP product provides a high temporal resolution (8-day) metric of vegetation growth which can be used to monitor short-term vegetation response to extreme events and implemented to derive vegetation phenology metrics; growing season start, end, and length, which can elucidate land cover and regionally specific vegetation responses to a changing climate. The high spatial resolution GPP and NPP indicators can also inform and clarify responses seen from other proposed Pilot Indicators such as forest growth/productivity, land cover, crop production, and phenology. The GPP and NPP data are in continuous production and will be sustained into the future with the next generation satellite missions. The long-term Ecosystem Productivity and Vegetation Health Indicators are ideal for use in sustained National Climate Assessments, providing regionally specific responses to a changing climate and complete coverage at the national scale.

  7. MODIFICATION OF VEGETABLE OILS FOR LUBRICANTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vegetable oils are recognized as rapidly biodegradable and are thus promising candidates as base fluids in environmental-friendly lubricants. Vegetable oils have excellent lubricity, but poor oxidation and low-temperature stability. This paper presents a series of structural modifications of veget...

  8. 21 CFR 73.260 - Vegetable juice.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Vegetable juice. 73.260 Section 73.260 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.260 Vegetable juice. (a) Identity. (1) The color additive vegetable juice is prepared either...

  9. New Sulfide Derivatives of Vegetable Oils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vegetable oils containing sulfide group were synthesized using a UV initiated thiol-ene reaction. The reaction involved addition of butyl thiol to the double bonds of the vegetable oil without the presence of a solvent. The effects of temperature, reaction time, type of vegetable oil, thiol to veg...

  10. BOUNDARY SHEAR STRESS ALONG VEGETATED STREAMBANKS

    EPA Science Inventory

    This research is intended to improve our understanding of the role of riparian vegetation in stream morphology by evaluating the effects of vegetation on boundary shear stress, providing insight to the type and density of vegetation required for streambank stability. The resu...

  11. Remote sensing of vegetation and soil

    NASA Technical Reports Server (NTRS)

    Schutt, J. B.; Auer, S. O.

    1977-01-01

    Microwave ellipsometry apparatus reflects circularly polarized train of microwaves from vegetation at predetermined angle of incidence to determine ratio of intensities of electric field components and their phase differences. Refractive index given by water content of vegetation and thickness of vegetation layer are computed from formula based on Maxwell's equations.

  12. Vegetable oils: liquid coolants for solar heating and cooling applications

    SciTech Connect

    Ingley, H A

    1980-02-01

    It has been proposed that vegetable oils, renewable byproducts of agriculture processes, be investigated for possible use as liquid coolants. The major thrust of the project was to investigate several thermophysical properties of the four vegetable oils selected. Vapor pressures, specific heat, viscosity, density, and thermal conductivity were determined over a range of temperatures for corn, soybean, peanut, and cottonseed oil. ASTM standard methods were used for these determinations. In addition, chemical analyses were performed on samples of each oil. The samples were collected before and after each experiment so that any changes in composition could be noted. The tests included iodine number, fatty acid, and moisture content determination. (MHR)

  13. Importance of vegetation dynamics for future terrestrial carbon cycling

    NASA Astrophysics Data System (ADS)

    Ahlström, Anders; Xia, Jianyang; Arneth, Almut; Luo, Yiqi; Smith, Benjamin

    2015-05-01

    Terrestrial ecosystems currently sequester about one third of anthropogenic CO2 emissions each year, an important ecosystem service that dampens climate change. The future fate of this net uptake of CO2 by land based ecosystems is highly uncertain. Most ecosystem models used to predict the future terrestrial carbon cycle share a common architecture, whereby carbon that enters the system as net primary production (NPP) is distributed to plant compartments, transferred to litter and soil through vegetation turnover and then re-emitted to the atmosphere in conjunction with soil decomposition. However, while all models represent the processes of NPP and soil decomposition, they vary greatly in their representations of vegetation turnover and the associated processes governing mortality, disturbance and biome shifts. Here we used a detailed second generation dynamic global vegetation model with advanced representation of vegetation growth and mortality, and the associated turnover. We apply an emulator that describes the carbon flows and pools exactly as in simulations with the full model. The emulator simulates ecosystem dynamics in response to 13 different climate or Earth system model simulations from the Coupled Model Intercomparison Project Phase 5 ensemble under RCP8.5 radiative forcing. By exchanging carbon cycle processes between these 13 simulations we quantified the relative roles of three main driving processes of the carbon cycle; (I) NPP, (II) vegetation dynamics and turnover and (III) soil decomposition, in terms of their contribution to future carbon (C) uptake uncertainties among the ensemble of climate change scenarios. We found that NPP, vegetation turnover (including structural shifts, wild fires and mortality) and soil decomposition rates explained 49%, 17% and 33%, respectively, of uncertainties in modelled global C-uptake. Uncertainty due to vegetation turnover was further partitioned into stand-clearing disturbances (16%), wild fires (0%), stand

  14. Shortwave infrared detection of vegetation

    NASA Technical Reports Server (NTRS)

    Goward, S. N. (Principal Investigator)

    1985-01-01

    The potential of short wave infrared (SWIR) measurements in vegetation discrimination is further substantiated through a discussion of field studies and an examination of the physical bases which cause SWIR measurements to vary with the vegetation type observed. The research reported herein supported the AGRISTARS program objective to incorporate TM measurements in the analysis of agricultural activity. Field measurements on corn and soybeans in Iowa were conducted, and the mean and variance of canopy reflectance were computed for each observation date. The Suits canopy reflectance model was used to evaluate possible explanations of the observed corn/soybeans reflectance patterns /39/. The SWIR measurements were shown to effectively discriminate corn and soybeans on the basis of leaf absorption properties.

  15. Hyperspectral remote sensing of vegetation

    USGS Publications Warehouse

    Thenkabail, Prasad S.; Lyon, John G.; Huete, Alfredo

    2011-01-01

    Hyperspectral narrow-band (or imaging spectroscopy) spectral data are fast emerging as practical solutions in modeling and mapping vegetation. Recent research has demonstrated the advances in and merit of hyperspectral data in a range of applications including quantifying agricultural crops, modeling forest canopy biochemical properties, detecting crop stress and disease, mapping leaf chlorophyll content as it influences crop production, identifying plants affected by contaminants such as arsenic, demonstrating sensitivity to plant nitrogen content, classifying vegetation species and type, characterizing wetlands, and mapping invasive species. The need for significant improvements in quantifying, modeling, and mapping plant chemical, physical, and water properties is more critical than ever before to reduce uncertainties in our understanding of the Earth and to better sustain it. There is also a need for a synthesis of the vast knowledge spread throughout the literature from more than 40 years of research.

  16. Diesel fuels from vegetable oils

    SciTech Connect

    Schwab, A.W.; Bagby, M.O.; Freedman, B.

    1986-03-01

    Vegetable oils have heat contents approximately 90% that of diesel fuel and are potential alternate fuel candidates. A major obstacle deterring their use in the direct-injection diesel engine is their inherent high viscosities which are nearly 10 times that of diesel fuel. Solution to the viscosity problem has been approached in three ways: 1) microemulsification, 2) pyrolysis, and 3) transesterification. Microemulsification with short chain alcohols such as methanol and ethanol yields fuels that are clear, thermodynamically stable liquid systems with viscosities near the ASTM specified range for number2 diesel fuel. These micellar systems may be formulated ionically or nonionically. The alcohols are attractive from an economic as well as a renewable resource viewpoint. Methanol has an economic advantage over ethanol, and it can be derived from a large variety of base stocks. These include biomass, municipal waste, natural gas being flared at refineries and from coal. Pyrolysis of vegetable oils is another approach to lowering their viscosity. Soybean and safflower oils were thermally decomposed in both air and nitrogen to obtain fuels for the diesel engine. Using standard ASTM distillation conditions, yields of pyrolysis products were about 75%. GS-MS analysis of the distillates showed the presence of alkanes, alkenes, aromatics, and carboxylic acids with carbon numbers ranging from 4 to more than 20. Fuel properties of the thermal decomposition products were substantially improved as evaluated by lower viscosities and higher cetane numbers compared to the unpyrrolyzed vegetable oils. Simple esters from transesterification of vegetable oils perform well in engine tests, and thus show good promise as an alternative or emergency fuel for diesel engines.

  17. Responses of Hyalella azteca to a Pesticide-Nutrient Mixture in Vegetated and Non-vegetated Wetland Mesocosms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aquatic vegetation has been shown to improve water quality by trapping and processing contaminants such as pesticides, nutrients and sediments. Currently there is little information regarding effects of pesticide and nutrient mixtures on aquatic biota in these systems and the influence aquatic vege...

  18. Experimental characterization of vegetation uprooting by flow

    NASA Astrophysics Data System (ADS)

    Edmaier, K.; Crouzy, B.; Perona, P.

    2015-09-01

    We investigate vegetation uprooting by flow for Avena sativa seedlings with stem-to-sediment size ratio close to unity and vanishing obstacle-induced scouring. By inducing parallel riverbed erosion within an experimental flume, we measure the time-to-uprooting in relation to root anchoring and flow drag forces. We link the erosion rate to the uprooting timescales for seedlings with varying mean root length. We show that the process of continuous erosion leading to uprooting resembles that of mechanical fatigue where system collapsing occurs after a given exposure time. By this analogy, we also highlight the nonlinear role of the residual root anchoring versus the flow drag acting on the canopy when uprooting occurs. As a generalization, we propose a framework to extend our results to time-dependent erosion rates, which typically occur for real river hydrographs. Finally, we discuss how the characteristic timescale of plant uprooting by flow erosion suggests that vegetation survival is conditioned by multiple erosion events and their interarrival time.

  19. Carbon Dioxide and Vegetation Water Use

    SciTech Connect

    Ball, J.T.; Peterson, A.G.; Hoylman, A.M.; Luo, Y.; Sims, D.A.; Johnson, D.W.; Coleman, J.S.; Ross, P.D.; Cheng, W.

    1996-12-01

    Evapo-transpiration from vegetation, as well as patterns of precipitation are expected to change as the concentration of CO{sub 2} in the atmosphere continues to rise (f). Water modulates the rates of many biogeochemical processes, and it has been estimated that water directly limits plant productivity over two-thirds of the earth's land surface (2). Water quality and availability are increasingly important practical issues as demands by both agricultural and urban users continue to increase. In a recent Perspective article (3) Farquhar stated that transpiration (water loss) from terrestrial vegetation will decline by 40 to 50% as the CO{sub 2} concentration in the atmosphere approaches twice present levels. He suggested that ''the impending saving of water would be a welcome result of the rising atmospheric CO{sub 2} concentration.'' We can confirm that large reductions in transpiration are expected by terrestrial physiological ecologists. Examining 35 recent articles that discussed the issue of water use while synthesizing research on ecosystem impacts of doubling atmospheric CO{sub 2} (including reviews and crop/natural ecosystem models), we found that 31 articles suggest that reductions in water use of between 25 and 50% are to be expected.

  20. Exploring the Relationship Between Water Flux and Vegetation Water Status Using Time Series Data of Evapotranspiration and Modis Vegetation Indices

    NASA Astrophysics Data System (ADS)

    Cheng, T.; Riaño, D.; Ustin, S.

    2012-12-01

    In agricultural practices, evapotranspiration (ET) data obtained from weather stations or flux towers are used to monitor crop water use and schedule irrigation over the growing season. Recent advances in remote sensing have shown that satellite data (e.g., MODIS) can be used to quantify the amount of water held in vegetation canopies. However, the relationship between how much water has been used through the ET process and how much water is maintained in vegetation canopies remains unclear. This study aimed to investigate how vegetation canopy water content is related to ET for almond orchards in the southern San Joaquin Valley of California. MODIS Nadir BRDF-Adjusted Reflectance 8-day 500 m data for the growing season of 2011 (March ~ November of 2011) were used to derive a number of vegetation indices as spectral indicators of canopy water content, including the Normalized Difference Vegetation Index (NDVI), the Enhanced Vegetation Index (EVI), the Normalized Difference Water Index (NDWI), the Normalized Difference Infrared Index using MODIS Band 6 (NDII) and the Normalized Difference Infrared Index using MODIS Band 7 (NDII7). These times series of MODIS indices were then compared to flux tower-based ET measurements temporally integrated from half-hourly to 8 days for the same time period. Our results showed all vegetation indices could account for more than 70% of variation in the ET data and the two infrared indices (NDII and NDII7) explained more than the other three indices. The relationships between vegetation indices and ET were generally positive and rate of ET change increased while the water content in almond canopies increased. The seasonal trajectory of ET could be fitted by a Gaussian function, with the ET peaking at day of year (DOY) 179. All vegetation indices exhibited broader peaking periods than ET due to insensitivity of spectral signals to fully developed canopies. The Gaussian function fitted to the NDII trajectory had the peaking day closest

  1. Vegetation forcing and convective motion

    SciTech Connect

    Hong, X.; Leach, M.J.; Raman, S.

    1995-04-01

    A large irrigated vegetation area in a semiarid or relatively dry location is a strong surface forcing of thermal circulations. Several observational studies have found that such thermally induced mesoscale circulation may contribute to the triggering and development of convective clouds. In the western United States, extensive areas of irrigated farmland are surrounded by hot, dry surfaces, such as a steppe. Substantial gradients of sensible heating in the horizontal direction lead to a {open_quotes}farm breeze{close_quotes} circulation from the cooler agricultural area to the warmer steppes found at Boardman, Oregon. These thermally forced circulations may trigger convection by the related convergence and updraft motion under favorable atmospheric conditions. The role of vegetative covering in convective motion is investigated using a mesoscale numerical model. Two- and three-dimensional simulations are described. The effects of atmospheric stability, moisture in the lower atmosphere, moisture in the upper atmosphere, and horizontal heating scale on thermally induced clouds are studied. The horizontal scale of inhomogeneity is also studied using the two-dimensional model. Finally, a realistic vegetation distribution similar to that of the Boardman Regional Flux Experiment is used in the three-dimensional simulations.

  2. Ecology of bison, elk, and vegetation in an arid ecosystem

    USGS Publications Warehouse

    Schoenecker, Kathryn A.; Advised by Hobbs, N. Thompson

    2012-01-01

    Herbivory has profound effects on vegetation production and structure in many different plant communities. The influence of herbivory on plants and ultimately ecosystem processes is shaped by the types of plants consumed, the intensity of herbivory, the evolutionary history of grazing, and the availability of water and nutrients to plants. The effect of ungulate herbivores on vegetation is of great interest to ecologists, land managers and agriculturalists. In addition, the Department of Interior recently established a Bison Conservation Initiative to provide for the conservation and restoration of North American plains- and wood bison, which includes establishing new populations and expanding existing populations. The San Luis Valley, Colorado, is being considered as a potential location for a bison conservation herd. Resource managers need to know the vegetation impacts of adding a second large ungulate to a system that already has elk.

  3. Slow recovery in desert perennial vegetation following prolonged human disturbance

    USGS Publications Warehouse

    Guo, Q.

    2004-01-01

    The study shows an exceptionally long-term recovery of perennial vegetation from prolonged heavy grazing and other human impacts. Since protection in 1906, overall species richness and habitat heterogeneity at the study site continued to increase until the 1960s when diversity, density and cover stabilized. During the same period, overall plant density and cover also increased. Species turnover increased gradually with time but no significant relation between any of the three community variables and precipitation or Palmer Drought Severity Index (PDSI) was detected. The increases in plant species richness, density, and cover of the perennial vegetation were mostly due to the increase of herbaceous species, especially palatable species. The lack of clear relationship between environment (e.g., precipitation) and community variables suggests that site history and plant life history must be taken into account in examining the nature of vegetation recovery process after disturbances.

  4. Polyamines in conventional and organic vegetables exposed to exogenous ethylene.

    PubMed

    Rossetto, Maria Rosecler Miranda; Vianello, Fabio; Saeki, Margarida Juri; Lima, Giuseppina Pace Pereira

    2015-12-01

    Relationships between endogenous levels of polyamines by thin layer chromatography (TLC) and gas chromatography (GC), nitrate and response to the application of ethylene were established between organic and conventional vegetables (broccoli, collard greens, carrots and beets), both raw and cooked. Responses to ethylene showed that organic plants were less responsive to the growth regulator. The levels of free polyamines obtained by TLC were higher in organic vegetables. Organic broccoli showed higher levels of putrescine (Put), and cooking resulted in lowering the overall content of these amines. Conventional collard green showed the highest level of putrescine in the leaves compared with organic. Tubers of carrots and beets contain the highest levels of Put. These plants also contain high levels of spermine. GC analysis showed the highest polyamines contents compared with those obtained by TLC. Cooking process decreased putrescine and cadaverine content, both in conventionally and organically grown vegetables. Organic beets contain lower NO3(-) compared with its conventional counterpart. PMID:26041185

  5. Interpretation of surface and planetary directional albedos for vegetated regions

    NASA Technical Reports Server (NTRS)

    Cess, Robert D.; Vulis, Inna L.

    1989-01-01

    An atmospheric solar radiation model has been coupled with surface reflectance measurements for two vegetation types, pasture land and savannah, in order to address several issues associated with understanding the directional planetary albedo; i.e., the dependence of planetary albedo upon solar zenith angle. These include an elucidation of processes that influence the variation of planetary albedo with solar zenith angle, as well as emphasizing potential problems associated with converting narrowband planetary albedo measurements to broadband quantities. It is suggested that, for vegetated surfaces, this latter task could be somewhat formidable, since the model simulations indicate that narrowband to broadband conversions strongly depend upon vegetation type. A further aspect of this paper is to illustrate a procedure by which reciprocity inconsistencies within a bidirectional reflectance dataset, if they are not too severe, can be circumvented.

  6. Effects of vegetation canopy on the radar backscattering coefficient

    NASA Technical Reports Server (NTRS)

    Mo, T.; Blanchard, B. J.; Schmugge, T. J.

    1983-01-01

    Airborne L- and C-band scatterometer data, taken over both vegetation-covered and bare fields, were systematically analyzed and theoretically reproduced, using a recently developed model for calculating radar backscattering coefficients of rough soil surfaces. The results show that the model can reproduce the observed angular variations of radar backscattering coefficient quite well via a least-squares fit method. Best fits to the data provide estimates of the statistical properties of the surface roughness, which is characterized by two parameters: the standard deviation of surface height, and the surface correlation length. In addition, the processes of vegetation attenuation and volume scattering require two canopy parameters, the canopy optical thickness and a volume scattering factor. Canopy parameter values for individual vegetation types, including alfalfa, milo and corn, were also determined from the best-fit results. The uncertainties in the scatterometer data were also explored.

  7. A vital link: water and vegetation in the Anthropocene

    NASA Astrophysics Data System (ADS)

    Gerten, D.

    2013-04-01

    This paper argues that the interplay of water, carbon and vegetation dynamics is fundamental to some global trends in the current and conceivable future Anthropocene. Supported by simulations with a process-based biosphere model and a literature review, it demonstrates that the connectivity of freshwater and vegetation dynamics is vital for water security, food security and (terrestrial) ecosystem integrity alike. The water limitation of net primary production of both natural and agricultural plants - already pronounced in many regions - is shown to increase in many places under projected climate change, though this development is partially offset by water-saving direct CO2 effects. Natural vegetation can to some degree adapt dynamically to higher water limitation, but agricultural crops require some form of active management to overcome it - among them irrigation, soil conservation and expansion into still uncultivated areas. While crucial to secure food production for a growing world population, such human interventions in water-vegetation systems have, as also shown, repercussions to the water cycle. Indeed, land use changes have been shown to be the second-most important influence on the terrestrial water balance in recent times. Furthermore, climate change regionally increases irrigation demand and decreases freshwater availability, impeding on rainfed and irrigated food production (if not CO2 effects counterbalance this impact - which is unlikely at least in poorly managed systems). Drawing from these exemplary investigations, some research perspectives on how to further improve our quantitative knowledge of human-water-vegetation interactions in the Anthropocene are outlined.

  8. Modeling the interaction between flow and highly flexible aquatic vegetation

    NASA Astrophysics Data System (ADS)

    Dijkstra, J. T.; Uittenbogaard, R. E.

    2010-12-01

    Aquatic vegetation has an important role in estuaries and rivers by acting as bed stabilizer, filter, food source, and nursing area. However, macrophyte populations worldwide are under high anthropogenic pressure. Protection and restoration efforts will benefit from more insight into the interaction between vegetation, currents, waves, and sediment transport. Most aquatic plants are very flexible, implying that their shape and hence their drag and turbulence production depend on the flow conditions. We have developed a numerical simulation model that describes this dynamic interaction between very flexible vegetation and a time-varying flow, using the sea grass Zostera marina as an example. The model consists of two parts: an existing 1DV k-ɛ turbulence model simulating the flow combined with a new model simulating the bending of the plants, based on a force balance that takes account of both vegetation position and buoyancy. We validated this model using observations of positions of flexible plastic strips and of the forces they are subjected to, as well as hydrodynamic measurements. The model predicts important properties like the forces on plants, flow velocity profiles, and turbulence characteristics well. Although the validation data are limited, the results are sufficiently encouraging to consider our model to be of generic value in studying flow processes in fields of flexible vegetation.

  9. Bed Shear Stress in Channels with Emergent Vegetation

    NASA Astrophysics Data System (ADS)

    Yang, Q.; Kerger, F.; Nepf, H. M.

    2014-12-01

    The shear stress at the bed of a channel influences important benthic processes such as sediment transport. Several methods exist to estimate the bed shear stress in open channel flow, but most of these are not appropriate for vegetated channels due to the impact of vegetation on the velocity profile and turbulence production. This study proposes a new model to estimate the bed shear stress in both vegetated and bare channels. The model is based on the observation that, for both bare and vegetated channels, within a viscous sub-layer at the bed, the viscous stress decreases linearly with increasing distance from the bed, resulting in a parabolic velocity profile at the bed. For emergent canopies of sufficient density, the thickness of this linear-stress layer is set by the stem diameter, leading to a simple estimate for bed shear stress. For bare channels, the model describes the velocity profile in the overlap region of the Law of the Wall. The model is supported by high-resolution experiments. Furthermore, the changes in turbulence isotropy and integral length across a range of vegetation density, from bare bed to dense canopy, have been explored.

  10. Salt marsh vegetation promotes efficient tidal channel networks

    NASA Astrophysics Data System (ADS)

    Kearney, W. S.; Fagherazzi, S.

    2014-12-01

    Tidal channel networks mediate the exchange of water, nutrients and sediment between an estuary and marshes and mudflats. Biology feeds back into channel morphodynamics through vegetation's influence on the cohesive strength of channel banks. Understanding the morphology of a tidal channel network is thus essential to understanding both the biological functioning of intertidal ecosystems and the topographic signature of life. A critical measure of the morphology of a channel network is the unchanneled path length, which is characteristic of the efficiency with which a network dissects the marsh platform. However, the processes which control the formation and maintenance of an efficient tidal channel network remain unclear. Here we show that an unvegetated marsh platform (Estero La Ramada, Baja California, Mexico) is dissected by a less efficient channel network than a vegetated one (Barnstable, Massachusetts, United States). The difference in geometric efficiency reflects a difference in the branching and meandering characteristics of the network, characteristics controlled by the density of vegetation on the channel banks. Our results suggest a feedback between network geometry and vegetation, mediated by fluxes of nutrients and salinity through the channel network, maintains the observed network geometries. An efficient network can support a denser vegetation community which stabilizes channel banks, leading to an efficient meandering geometry.

  11. Advanced preservation methods and nutrient retention in fruits and vegetables.

    PubMed

    Barrett, Diane M; Lloyd, Beate

    2012-01-15

    Despite the recommendations of international health organizations and scientific research carried out around the world, consumers do not take in sufficient quantities of healthy fruit and vegetable products. The use of new, 'advanced' preservation methods creates a unique opportunity for food manufacturers to retain nutrient content similar to that found in fresh fruits and vegetables. This review presents a summary of the published literature regarding the potential of high-pressure and microwave preservation, the most studied of the 'advanced' processes, to retain the natural vitamin A, B, C, phenolic, mineral and fiber content in fruits and vegetables at the time of harvest. Comparisons are made with more traditional preservation methods that utilize thermal processing. Case studies on specific commodities which have received the most attention are highlighted; these include apples, carrots, oranges, tomatoes and spinach. In addition to summarizing the literature, the review includes a discussion of postharvest losses in general and factors affecting nutrient losses in fruits and vegetables. Recommendations are made for future research required to evaluate these advanced process methods. PMID:22102258

  12. Vegetation management with fire modifies peatland soil thermal regime.

    PubMed

    Brown, Lee E; Palmer, Sheila M; Johnston, Kerrylyn; Holden, Joseph

    2015-05-01

    Vegetation removal with fire can alter the thermal regime of the land surface, leading to significant changes in biogeochemistry (e.g. carbon cycling) and soil hydrology. In the UK, large expanses of carbon-rich upland environments are managed to encourage increased abundance of red grouse (Lagopus lagopus scotica) by rotational burning of shrub vegetation. To date, though, there has not been any consideration of whether prescribed vegetation burning on peatlands modifies the thermal regime of the soil mass in the years after fire. In this study thermal regime was monitored across 12 burned peatland soil plots over an 18-month period, with the aim of (i) quantifying thermal dynamics between burned plots of different ages (from <2 to 15 + years post burning), and (ii) developing statistical models to determine the magnitude of thermal change caused by vegetation management. Compared to plots burned 15 + years previously, plots recently burned (<2-4 years) showed higher mean, maximum and range of soil temperatures, and lower minima. Statistical models (generalised least square regression) were developed to predict daily mean and maximum soil temperature in plots burned 15 + years prior to the study. These models were then applied to predict temperatures of plots burned 2, 4 and 7 years previously, with significant deviations from predicted temperatures illustrating the magnitude of burn management effects. Temperatures measured in soil plots burned <2 years previously showed significant statistical disturbances from model predictions, reaching +6.2 °C for daily mean temperatures and +19.6 °C for daily maxima. Soil temperatures in plots burnt 7 years previously were most similar to plots burned 15 + years ago indicating the potential for soil temperatures to recover as vegetation regrows. Our findings that prescribed peatland vegetation burning alters soil thermal regime should provide an impetus for further research to understand the consequences of thermal regime

  13. Assessments of recent tundra change based on repeated vegetation surveys

    NASA Astrophysics Data System (ADS)

    Elmendorf, S.; Henry, G.; Thetundra Vegetation Change Group

    2010-12-01

    Results from experimental warming studies suggest tundra vegetation will respond rapidly and dramatically to climate warming, and indeed, NDVI data from remote sensing and repeat aerial photography suggest such changes may already be occurring. NDVI changes, however, may reflect responses to a variety of processes. Repeat measurements of permanently marked plots offer an invaluable opportunity to monitor detailed changes in vegetation composition and abundance. Here, we report results from a synthesis of repeat measurements of 195 permanent plots in Arctic and alpine tundra plant communities in North America (90 plots), Europe (82 plots), Asia (10 plots), Australia (12 plots), and Antarctica (1 plot) that were revisited at least twice between 1980 and 2010, with an average timespan of 13 years between first and last sampling periods. Annual air-temperature warming over the sampling period varied considerably among sites, ranging from slight cooling to increases of nearly 2°C per decade. In our preliminary analyses, we found significant tundra-wide increases in vegetation height as well as abundance of evergreen shrubs and graminoids, but declines in mosses. We anticipated that changes in vegetation height, abundance of deciduous shrubs, and percent of vegetated ground would be highest in areas where climate warming is occurring most rapidly, but found no support for these predictions in our observational dataset. It is possible that local vegetation dynamics in these areas are affected more by other longer-term non-equilibrium processes such as recovery from glaciation, or an alternative suite of local drivers, such as snow cover, precipitation, disturbance or herbivory.

  14. Health Benefits of Fruits and Vegetables1

    PubMed Central

    Slavin, Joanne L.; Lloyd, Beate

    2012-01-01

    Fruits and vegetables are universally promoted as healthy. The Dietary Guidelines for Americans 2010 recommend you make one-half of your plate fruits and vegetables. Myplate.gov also supports that one-half the plate should be fruits and vegetables. Fruits and vegetables include a diverse group of plant foods that vary greatly in content of energy and nutrients. Additionally, fruits and vegetables supply dietary fiber, and fiber intake is linked to lower incidence of cardiovascular disease and obesity. Fruits and vegetables also supply vitamins and minerals to the diet and are sources of phytochemicals that function as antioxidants, phytoestrogens, and antiinflammatory agents and through other protective mechanisms. In this review, we describe the existing dietary guidance on intake of fruits and vegetables. We also review attempts to characterize fruits and vegetables into groups based on similar chemical structures and functions. Differences among fruits and vegetables in nutrient composition are detailed. We summarize the epidemiological and clinical studies on the health benefits of fruits and vegetables. Finally, we discuss the role of fiber in fruits and vegetables in disease prevention. PMID:22797986

  15. Health benefits of fruits and vegetables.

    PubMed

    Slavin, Joanne L; Lloyd, Beate

    2012-07-01

    Fruits and vegetables are universally promoted as healthy. The Dietary Guidelines for Americans 2010 recommend you make one-half of your plate fruits and vegetables. Myplate.gov also supports that one-half the plate should be fruits and vegetables. Fruits and vegetables include a diverse group of plant foods that vary greatly in content of energy and nutrients. Additionally, fruits and vegetables supply dietary fiber, and fiber intake is linked to lower incidence of cardiovascular disease and obesity. Fruits and vegetables also supply vitamins and minerals to the diet and are sources of phytochemicals that function as antioxidants, phytoestrogens, and antiinflammatory agents and through other protective mechanisms. In this review, we describe the existing dietary guidance on intake of fruits and vegetables. We also review attempts to characterize fruits and vegetables into groups based on similar chemical structures and functions. Differences among fruits and vegetables in nutrient composition are detailed. We summarize the epidemiological and clinical studies on the health benefits of fruits and vegetables. Finally, we discuss the role of fiber in fruits and vegetables in disease prevention. PMID:22797986

  16. Modeling the effects of vegetation on methane oxidation and emissions through soil landfill final covers across different climates.

    PubMed

    Abichou, Tarek; Kormi, Tarek; Yuan, Lei; Johnson, Terry; Francisco, Escobar

    2015-02-01

    Plant roots are reported to enhance the aeration of soil by creating secondary macropores which improve the diffusion of oxygen into soil as well as the supply of methane to bacteria. Therefore, methane oxidation can be improved considerably by the soil structuring processes of vegetation, along with the increase of organic biomass in the soil associated with plant roots. This study consisted of using a numerical model that combines flow of water and heat with gas transport and oxidation in soils, to simulate methane emission and oxidation through simulated vegetated and non-vegetated landfill covers under different climatic conditions. Different simulations were performed using different methane loading flux (5-200 g m(-2) d(-1)) as the bottom boundary. The lowest modeled surface emissions were always obtained with vegetated soil covers for all simulated climates. The largest differences in simulated surface emissions between the vegetated and non-vegetated scenarios occur during the growing season. Higher average yearly percent oxidation was obtained in simulations with vegetated soil covers as compared to non-vegetated scenario. The modeled effects of vegetation on methane surface emissions and percent oxidation were attributed to two separate mechanisms: (1) increase in methane oxidation associated with the change of the physical properties of the upper vegetative layer and (2) increase in organic matter associated with vegetated soil layers. Finally, correlations between percent oxidation and methane loading into simulated vegetated and non-vegetated covers were proposed to allow decision makers to compare vegetated versus non-vegetated soil landfill covers. These results were obtained using a modeling study with several simplifying assumptions that do not capture the complexities of vegetated soils under field conditions. PMID:25475118

  17. Microbiological Spoilage of Fruits and Vegetables

    NASA Astrophysics Data System (ADS)

    Barth, Margaret; Hankinson, Thomas R.; Zhuang, Hong; Breidt, Frederick

    Consumption of fruit and vegetable products has dramatically increased in the United States by more than 30% during the past few decades. It is also estimated that about 20% of all fruits and vegetables produced is lost each year due to spoilage. The focus of this chapter is to provide a general background on microbiological spoilage of fruit and vegetable products that are organized in three categories: fresh whole fruits and vegetables, fresh-cut fruits and vegetables, and fermented or acidified vegetable products. This chapter will address characteristics of spoilage microorganisms associated with each of these fruit and vegetable categories including spoilage mechanisms, spoilage defects, prevention and control of spoilage, and methods for detecting spoilage microorganisms.

  18. Estimating vegetation dryness to optimize fire risk assessment with spot vegetation satellite data in savanna ecosystems

    NASA Astrophysics Data System (ADS)

    Verbesselt, J.; Somers, B.; Lhermitte, S.; van Aardt, J.; Jonckheere, I.; Coppin, P.

    2005-10-01

    The lack of information on vegetation dryness prior to the use of fire as a management tool often leads to a significant deterioration of the savanna ecosystem. This paper therefore evaluated the capacity of SPOT VEGETATION time-series to monitor the vegetation dryness (i.e., vegetation moisture content per vegetation amount) in order to optimize fire risk assessment in the savanna ecosystem of Kruger National Park in South Africa. The integrated Relative Vegetation Index approach (iRVI) to quantify the amount of herbaceous biomass at the end of the rain season and the Accumulated Relative Normalized Difference vegetation index decrement (ARND) related to vegetation moisture content were selected. The iRVI and ARND related to vegetation amount and moisture content, respectively, were combined in order to monitor vegetation dryness and optimize fire risk assessment in the savanna ecosystems. In situ fire activity data was used to evaluate the significance of the iRVI and ARND to monitor vegetation dryness for fire risk assessment. Results from the binary logistic regression analysis confirmed that the assessment of fire risk was optimized by integration of both the vegetation quantity (iRVI) and vegetation moisture content (ARND) as statistically significant explanatory variables. Consequently, the integrated use of both iRVI and ARND to monitor vegetation dryness provides a more suitable tool for fire management and suppression compared to other traditional satellite-based fire risk assessment methods, only related to vegetation moisture content.

  19. Relationships between vegetation indices and different burn and vegetation ratios: a multi-scale approach applied in a fire affected area

    NASA Astrophysics Data System (ADS)

    Pleniou, M.; Koutsias, N.

    2013-08-01

    Vegetation indices have been widely used in remote sensing literature for burned land mapping and monitoring. In the present study we used satellite data (IKONOS, LANDSAT, ASTER, MODIS) of multiple spectral (visible, near, shortwave infrared) and spatial (1-500 meters) resolutions, acquired shortly after a very destructive fire occurred in the mountain of Parnitha in Attica, Greece the summer of 2007. The aim of our study is to examine and evaluate the performance of some vegetation indices for burned land mapping and also to characterize the relationships between vegetation indices and the percent of fire-scorched (burned) and non fire-scorched (vegetated) areas. The available satellite images were processed geometrically, radiometrically and atmospherically. The very high resolution IKONOS imagery was served as a base to estimate the percent of cover of burned areas, bare soil and vegetation by applying the maximum likelihood classification algorithm. The percent of cover for each type was then correlated to vegetation indices for all the satellite images, and regression models were fit to characterize those relationships. In total 57 versions of some classical vegetation indices were computed using LANDSAT, ASTER and MODIS data. Most of them were modified by replacing Red with SWIR channel, as the latter has been proved sensitive to burned area discrimination. IPVI and NDVI showed a better performance among the indices tested to estimate the percent of vegetation, while most of the modified versions of the indices showed highest performance to estimate the percent of burned areas.

  20. Integrated modeling framework to quantify the coastal protection services supplied by vegetation

    NASA Astrophysics Data System (ADS)

    Guannel, Greg; Ruggiero, Peter; Faries, Joe; Arkema, Katie; Pinsky, Malin; Gelfenbaum, Guy; Guerry, Anne; Kim, Choong-Ki

    2015-01-01

    can protect communities by reducing nearshore wave height and altering sediment transport processes. However, quantitative approaches for evaluating the coastal protection services, or benefits, supplied by vegetation to people in a wide range of coastal environments are lacking. To begin to fill this knowledge gap, we propose an integrated modeling approach for quantifying how vegetation modifies nearshore processes—including the attenuation of wave height, mean and total water level—and reduces shoreline erosion during storms. We apply the model to idealized seagrass-sand and mangrove-mud cases, and illustrate its potential by quantifying how those habitats reduce water levels and sediment loss beyond what would be observed in the absence of vegetation. The integrated modeling approach provides an efficient way to quantify the coastal protection services supplied by vegetation and highlights specific research needs for improved representations of the ways in which vegetation modifies wave-induced processes.

  1. Arctic Browning: vegetation damage and implications for carbon balance.

    NASA Astrophysics Data System (ADS)

    Treharne, Rachael; Bjerke, Jarle; Emberson, Lisa; Tømmervik, Hans; Phoenix, Gareth

    2016-04-01

    'Arctic browning' is the loss of biomass and canopy in Arctic ecosystems. This process is often driven by climatic and biological extreme events - notably extreme winter warm periods, winter frost-drought and severe outbreaks of defoliating insects. Evidence suggests that browning is becoming increasingly frequent and severe at the pan-arctic scale, a view supported by observations from more intensely observed regions, with major and unprecedented vegetation damage reported at landscape (>1000km2) and regional (Nordic Arctic Region) scales in recent years. Critically, the damage caused by these extreme events is in direct opposition to 'Arctic greening', the well-established increase in productivity and shrub abundance observed at high latitudes in response to long-term warming. This opposition creates uncertainty as to future anticipated vegetation change in the Arctic, with implications for Arctic carbon balance. As high latitude ecosystems store around twice as much carbon as the atmosphere, and vegetation impacts are key to determining rates of loss or gain of ecosystem carbon stocks, Arctic browning has the potential to influence the role of these ecosystems in global climate. There is therefore a clear need for a quantitative understanding of the impacts of browning events on key ecosystem carbon fluxes. To address this, field sites were chosen in central and northern Norway and in Svalbard, in areas known to have been affected by either climatic extremes or insect outbreak and subsequent browning in the past four years. Sites were chosen along a latitudinal gradient to capture both conditions already causing vegetation browning throughout the Norwegian Arctic, and conditions currently common at lower latitudes which are likely to become more damaging further North as climate change progresses. At each site the response of Net Ecosystem CO2 Exchange to light was measured using a LiCor LI6400 Portable Photosynthesis system and a custom vegetation chamber with

  2. Base catalytic transesterification of vegetable oil.

    PubMed

    Mainali, Kalidas

    2012-01-01

    Sustainable economic and industrial growth requires safe, sustainable resources of energy. Biofuel is becoming increasingly important as an alternative fuel for the diesel engine. The use of non-edible vegetable oils for biofuel production is significant because of the increasing demand for edible oils as food. With the recent debate of food versus fuel, some non-edible oils like soapnut and Jatropha (Jatropha curcus. L) are being investigated as possible sources of biofuel. Recent research has focused on the application of heterogeneous catalysis. This review considers catalytic transesterification and the possibility of heterogeneous base catalysts. The process of transesterification, and the effect of parameters, mechanism and kinetics are reviewed. Although chromatography (GC and HPLC) are the analytical methods most often used for biofuel characterization, other techniques and some improvements to analytical methods are discussed. PMID:22574385

  3. Simulation of SAR backscatter for forest vegetation

    NASA Astrophysics Data System (ADS)

    Prajapati, Richa; Kumar, Shashi; Agrawal, Shefali

    2016-05-01

    Synthetic Aperture Radar (SAR) is one of the most recent imaging technology to study the forest parameters. The invincible characteristics of microwave acquisition in cloudy regions and night imaging makes it a powerful tool to study dense forest regions. A coherent combination of radar polarimetry and interferometry (PolInSAR) enhances the accuracy of retrieved biophysical parameters. This paper attempts to address the issue of estimation of forest structural information caused due to instability of radar platforms through simulation of SAR image. The Terai Central Forest region situated at Haldwani area in Uttarakhand state of India was chosen as the study area. The system characteristics of PolInSAR dataset of Radarsat-2 SAR sensor was used for simulation process. Geometric and system specifications like platform altitude, center frequency, mean incidence angle, azimuth and range resolution were taken from metadata. From the field data it was observed that average tree height and forest stand density were 25 m and 300 stems/ha respectively. The obtained simulated results were compared with the sensor acquired master and slave intensity images. It was analyzed that for co-polarized horizontal component (HH), the mean values of simulated and real master image had a difference of 0.3645 with standard deviation of 0.63. Cross-polarized (HV) channel showed better results with mean difference of 0.06 and standard deviation of 0.1 while co-polarized vertical component (VV) did not show similar values. In case of HV polarization, mean variation between simulated and real slave images was found to be the least. Since cross-polarized channel is more sensitive to vegetation feature therefore better simulated results were obtained for this channel. Further the simulated images were processed using PolInSAR inversion modelling approach using three different techniques DEM differencing, Coherence Amplitude Inversion and Random Volume over Ground Inversion. DEM differencing

  4. Asynchronous vegetation phenology enhances winter body condition of a large mobile herbivore.

    PubMed

    Searle, Kate R; Rice, Mindy B; Anderson, Charles R; Bishop, Chad; Hobbs, N T

    2015-10-01

    Understanding how spatial and temporal heterogeneity influence ecological processes forms a central challenge in ecology. Individual responses to heterogeneity shape population dynamics, therefore understanding these responses is central to sustainable population management. Emerging evidence has shown that herbivores track heterogeneity in nutritional quality of vegetation by responding to phenological differences in plants. We quantified the benefits mule deer (Odocoileus hemionus) accrue from accessing habitats with asynchronous plant phenology in northwest Colorado over 3 years. Our analysis examined both the direct physiological and indirect environmental effects of weather and vegetation phenology on mule deer winter body condition. We identified several important effects of annual weather patterns and topographical variables on vegetation phenology in the home ranges of mule deer. Crucially, temporal patterns of vegetation phenology were linked with differences in body condition, with deer tending to show poorer body condition in areas with less asynchronous vegetation green-up and later vegetation onset. The direct physiological effect of previous winter precipitation on mule deer body condition was much less important than the indirect effect mediated by vegetation phenology. Additionally, the influence of vegetation phenology on body fat was much stronger than that of overall vegetation productivity. In summary, changing annual weather patterns, particularly in relation to seasonal precipitation, have the potential to alter body condition of this important ungulate species during the critical winter period. This finding highlights the importance of maintaining large contiguous areas of spatially and temporally variable resources to allow animals to compensate behaviourally for changing climate-driven resource patterns. PMID:26009244

  5. Remote sensing analysis of forest vegetation changes due to climate and anthropogenic impacts

    NASA Astrophysics Data System (ADS)

    Zoran, M. A.; Zoran, L. F. V.; Dida, A. I.

    2009-09-01

    Forest vegetation interaction with climate and anthropogenic stressors is done through a series of complex feedbacks, which are not very well understood. The patterns of forest vegetation are highly determined by temperature, precipitation, solar irradiance, soil conditions and CO2 concentration. Vegetation impacts climate directly through moisture, energy, and momentum exchanges with the atmosphere and indirectly through biogeochemical processes that alter atmospheric CO2 concentration. Changes in forest vegetation land use/cover alter the surface albedo and radiation fluxes, leading to a local temperature change and eventually a vegetation response. This albedo (energy) feedback is particularly important when forests mask snow cover. Forest vegetation-climate feedback regimes are designated based on the temporal correlations between the vegetation and and the surface temperature and precipitation. The different feedback regimes are linked to the relative importance of vegetation and soil moisture in determining land-atmosphere interactions. The spatio-temporal dynamics are assessed in terms of the NDVI-surface temperature correlations. Observed vegetation feedbacks on temperature and precipitation are assessed based on Landsat TM, ETM, MODIS and IKONOS satellite data across some forested areas placed in North/Eastern part of Bucharest town as well as in Prahova Valley, Romania for 1989 -2007 period.

  6. Evaluating the impact of a wide range of vegetation densities on river channel pattern

    NASA Astrophysics Data System (ADS)

    Pattison, Ian; Roucou, Ron

    2016-04-01

    Braided rivers are very dynamic systems which have complex controls over their planform and flow dynamics. Vegetation is one variable which influences channel geometry and pattern, through its effect on local flow hydraulics and the process continuum of sediment erosion-transport-deposition. Furthermore, where in the braided floodplain stable vegetation develops depends on the temporal sequencing of the river discharge i.e. floods. Understanding the effect of vegetation in these highly dynamic systems has multiple consequences for human activity and floodplain management. This paper focusses on the specific role of vegetation density in controlling braided river form and processes. Previous research in this field has been contradictory; with Gran and Paola (2001) finding that increasing vegetation density decreased the number of active channels. In contrast, Coulthard (2005] observed that as vegetation become denser there was an increase in the number of channels. This was hypothesized to be caused by flow separation around vegetation and the development of bars immediately downstream of the plant. This paper reports the results from a set of experiments in a 4m by 1m flume, where discharge, slope and sediment size were kept constant. Artificial grass was used to represent vegetation with a density ranging from 50 plants/m2 to 400 plants/m2. Digital photographs, using a GoPro camera with a fish eye lens, were taken from ~1m above the flume at an interval of 30 seconds during the 3 hour experiment. The experiments showed that as the vegetation density increased from 50 to 150 plants/m2, the number of channel bars developing doubled from 12 to 24. At vegetation densities greater than 150 plants/m2 there was a decline in the number of bars created to a minimum of 8 bars for a density of 400 plants/m2. We attribute these patterns to the effect that the vegetation has on flow hydraulics, sediment transport processes and the spatial patterns of erosion and deposition. We

  7. Landform-Water-Vegetation Feedbacks: Exploring Ecosystem Stability and Restoration Potential in Semiarid Hillslopes

    NASA Astrophysics Data System (ADS)

    Moreno de las Heras, M.; Saco, P. M.; Merino-Martin, L.; Espigares, T.; Nicolau, J. M.

    2014-12-01

    Vegetation dynamics and soil surface processes (e.g. runoff, soil erosion, sedimentation) are tightly coupled in drylands, where vegetation cover is patchy and plant production largely depends on favourable redistribution of water and sediments. At the same time, the amount and spatial distribution of vegetation control hillslope runoff and erosion, and strongly influence the redistribution of water and soil resources in these systems. Large shifts in the structure and organization of vegetation are associated with land degradation, frequently involving nonlinear responses to both human and climatic pressures. The study of landform-water-vegetation feedbacks has, therefore, a critical role for the comprehension of ecosystem stability and restoration potential in arid and semiarid environments. We present a synthesis of field-based, remote-sensed and modelling studies on soil-vegetation patterns in semiarid rangelands of Australia and water-restricted reclaimed mining slopes of Spain. Our results indicate that the organization and stability of vegetation patterns strongly depends on feedbacks with coevolving landforms. Exploration of degradation trends in banded Mulga shrublands of central Australia reveals that human disturbances (e.g. grazing) can strongly alter landform-water-vegetation feedbacks and particularly the way water is spatially redistributed and used by vegetation, resulting in threshold-like responses of ecosystem function. Successful experiences on the restoration of these systems highlight that the management of runoff and sediment flows is decisive to recover vegetation patchiness and landscape function. The study of vegetation-water-landform feedbacks in Mediterranean-dry reclaimed mining slopes of Spain offers additional indications on the restoration of drylands, particularly on the effects of rill and gully erosion on the stability of restored vegetation. The development of rill and gully networks provides very efficient drainage networks for

  8. Vegetation fire proneness in Europe

    NASA Astrophysics Data System (ADS)

    Pereira, Mário; Aranha, José; Amraoui, Malik

    2015-04-01

    Fire selectivity has been studied for vegetation classes in terms of fire frequency and fire size in a few European regions. This analysis is often performed along with other landscape variables such as topography, distance to roads and towns. These studies aims to assess the landscape sensitivity to forest fires in peri-urban areas and land cover changes, to define landscape management guidelines and policies based on the relationships between landscape and fires in the Mediterranean region. Therefore, the objectives of this study includes the: (i) analysis of the spatial and temporal variability statistics within Europe; and, (ii) the identification and characterization of the vegetated land cover classes affected by fires; and, (iii) to propose a fire proneness index. The datasets used in the present study comprises: Corine Land Cover (CLC) maps for 2000 and 2006 (CLC2000, CLC2006) and burned area (BA) perimeters, from 2000 to 2013 in Europe, provided by the European Forest Fire Information System (EFFIS). The CLC is a part of the European Commission programme to COoRdinate INformation on the Environment (Corine) and it provides consistent, reliable and comparable information on land cover across Europe. Both the CLC and EFFIS datasets were combined using geostatistics and Geographical Information System (GIS) techniques to access the spatial and temporal evolution of the types of shrubs and forest affected by fires. Obtained results confirms the usefulness and efficiency of the land cover classification scheme and fire proneness index which allows to quantify and to compare the propensity of vegetation classes and countries to fire. As expected, differences between northern and southern Europe are notorious in what concern to land cover distribution, fire incidence and fire proneness of vegetation cover classes. This work was supported by national funds by FCT - Portuguese Foundation for Science and Technology, under the project PEst-OE/AGR/UI4033/2014 and by

  9. Mediterranean shrub vegetation: soil protection vs. water availability

    NASA Astrophysics Data System (ADS)

    García Estringana, Pablo; Nieves Alonso-Blázquez, M.; Alegre, Alegre; Cerdà, Artemi

    2014-05-01

    Soil Erosion and Land Degradation are closely related to the changes in the vegetation cover (Zhao et al., 2013). Although other factors such as rainfall intensiy or slope (Ziadat and Taimeh, 2013) the plant covers is the main factor that controls the soil erosion (Haregeweyn, 2013). Plant cover is the main factor of soil erosion processes as the vegetation control the infiltration and runoff generation (Cerdà, 1998a; Kargar Chigani et al., 2012). Vegetation cover acts in a complex way in influencing on the one hand on runoff and soil loss and on the other hand on the amount and the way that rainfall reaches the soil surface. In arid and semiarid regions, where erosion is one of the main degradation processes and water is a scant resource, a minimum percentage of vegetation coverage is necessary to protect the soil from erosion, but without compromising the availability of water (Belmonte Serrato and Romero Diaz, 1998). This is mainly controlled by the vegetation distribution (Cerdà, 1997a; Cammeraat et al., 2010; Kakembo et al., 2012). Land abandonment is common in Mediterranean region under extensive land use (Cerdà, 1997b; García-Ruiz, 2010). Abandoned lands typically have a rolling landscape with steep slopes, and are dominated by herbaceous communities that grow on pasture land interspersed by shrubs. Land abandonment use to trigger an increase in soil erosion, but the vegetation recovery reduces the impact of the vegetation. The goal of this work is to assess the effects of different Mediterranean shrub species (Dorycnium pentaphyllum Scop., Medicago strasseri, Colutea arborescens L., Retama sphaerocarpa, L., Pistacia Lentiscus L. and Quercus coccifera L.) on soil protection (runoff and soil losses) and on rainfall reaching soil surface (rainfall partitioning fluxes). To characterize the effects of shrub vegetation and to evaluate their effects on soil protection, two field experiments were carried out. The presence of shrub vegetation reduced runoff by

  10. Vegetation Hydrodynamics - Recent Developments and Future Challenges

    NASA Astrophysics Data System (ADS)

    Nepf, H. M.

    2014-12-01

    For over a century vegetation has been removed from channels and coastal zones to facilitate navigation and development. In recent decades, however, we have recognized the ecologic and economic benefits of aquatic vegetation. It buffers against coastal eutrophication, damps waves and coastal storm surge, provides habitat, inhibits bank erosion, and provides significant carbon storage. The management of watersheds and coastal zones has turned from vegetation removal to restoration. In the past 20 years, the study of vegetation hydrodynamics has accelerated to meet the need to understand feedbacks between vegetation, flow and sediment transport. This presentation will describe key features of vegetation hydrodynamics, first at the meadow scale and then at the scale of individual patches, examining how vegetation density and meadow (or patch) morphology impact flow, with subsequent implications for sediment fate. Finally, the talk highlights differences in turbulence generation between bare and vegetated beds that may limit the transfer of open channel sediment transport models to vegetated channels, creating the future challenge of defining sediment transport models appropriate for vegetated regions.

  11. Rapid screening of biologically modified vegetable oils for fuel performance

    SciTech Connect

    Geller, D.P.; Goodrum, J.W.; Campbell, C.C.

    1999-08-01

    A process for the rapid screening of alternative diesel fuel performance was applied to analogues of genetically modified vegetable oils and a mixture with no. 2 diesel fuel. The oils examined contained 60 to 70% of low molecular weight, short-chain, saturated triglycerides compared to the 1 to 2% found in traditional vegetable oils. These oils have relatively low viscosity that is predicted to enhance their performance as alternative diesel fuels. The screening process utilizes an engine torque test sequence that accelerates the tendency of diesel fuels to coke fuel injectors, a key indicator of fuel performance. The results of the tests were evaluated using a computer vision system for the rapid quantification of injector coking. The results of the screen were compared to those using no. 2 diesel fuel as a baseline. Coke deposition from the modified vegetable oil analogues was not found to be significantly different than deposition from diesel fuel. Suggestions are made to guide further modification of vegetable oil biosynthesis for the production of alternative diesel fuel.

  12. Geothermal vegetable dehydration at Brady`s Hot Springs, Nevada

    SciTech Connect

    Lund, J.W.

    1994-07-01

    This article describes the utilization of the Brady`s Springs geothermal resource for heat generation used in the food dehydration process. This geothermal system is located in the Forty-Mile Desert area of Nevada. Geothermal Food Processors, Inc. of Reno, Nevada started construction of the geothermal vegetable dehydration plant in 1978, and the plant started operations in 1979. The industrial process of vegetable dehydration at the plant is described. In July of 1992, the Brady`s Springs geothermal system began being used for power generation by the Brady`s Hot Springs geothermal power plant, operated by Oxbow Power Services, Inc. As a result, the water levels in the food processing plant wells have dropped below usable levels and the geothermal brine is now being supplied by the Oxbow power plant.

  13. Topographical and biophysical modeling of vegetation patterns at alpine treeline

    SciTech Connect

    Brown, D.G.

    1992-01-01

    Availability and abundance of several important topo-climatic elements explains much of the variation in the patterns of vegetation along the treeline ecotone. Active geomorphic and biophysical disturbance regimes in alpine areas introduce additional variability on the treeline transition. The purpose of this research was to model the spatial patterns of vegetation communities along the treeline ecotone relative to topo-climatic and disturbances processes. Surrogates of several topographically controlled climatic elements (solar radiation potential, soil moisture potential, and wind/snow potential) were constructed from digital elevation models (DEMs) for a study area in east-central Glacier National Park, Montana. Vegetation communities in the study area were characterized through statistical classification of Landsat Thematic Mapper digital data, field calibration, and validation. Topographical empirical Models of Treeline (TEMTREEs) were constructed to examine the relative importance of factors which affected the treeline transition. TEMTREEs were also evaluated as predictive tools for extending the analysis through additional variables representing multi-scale processes. Empirical models were constructed for selected elevation zones (from 1600 to 2350 meters a.m.s.l.) at 150 meter intervals. The Kappa statistic was used to assess the predictive ability of the models. The results suggested that the elevation gradient accounted for much of the variation in the vegetation patterns at alpine treeline. Geomorphic disturbance patterns, characterized by mapping talus slopes, snow avalanche paths, and slope angles greater than 34 degrees, consistently explained significant variations in the vegetation patterns. This finding suggests that predictions of treeline responses to climatic change must account for potential changes in the frequency and magnitude of geomorphic process disturbances.

  14. Effects of vegetation change on evapotranspiration in a semiarid shrubland of the Loess Plateau, China

    NASA Astrophysics Data System (ADS)

    Gong, T. T.; Lei, H. M.; Yang, D. W.; Jiao, Y.; Yang, H. B.

    2014-12-01

    Vegetation change is a primary factor that affect evapotranspiration (ET), which is an important process in the hydrological cycle. In this study, an attempt is made to analyze the effects of vegetation change on ET using continuous observation data from eddy-covariance (EC) measurements over three periods (1 July 2011 to 30 June 2014) of a study site in a sparse shrubland study site located in the Loess Plateau of China, which is a fragile ecosystem experiencing serious soil desiccation. In our study, vegetation change includes phenological change and land use change. Phenological process of vegetation is validated to have a remarkable positive effect on ET in a rate of 1.83 ± 0.01 along with vegetation greening. Land use change at our study site was due to the native vegetation being cut-off by human activities, converting sparse shrubland to bare soil. With land use condition changing during the three years, annual total ET was observed to increase 103 mm, suggesting that soil evaporation consumes more water than canopy transpiration. In summary, the effects of vegetation change on ET suggest that both vegetation greening and increased area of exposed soil would aggravate the soil desiccation at our site in the north Loess Plateau.

  15. Sensitivity of blanket peat vegetation and hydrochemistry to local disturbances.

    PubMed

    Robroek, Bjorn J M; Smart, Richard P; Holden, Joseph

    2010-10-01

    At the ecosystem scale, peatlands can be extremely resilient to perturbations. Yet, they are very sensitive to local disturbances, especially mechanical perturbations (e.g. trampling). The effects of these disturbances on vegetation, and potential effects on hydrochemical conditions along the peat surface, however, are largely unknown. We used three research tracks (paths researchers use to access their study sites) differing in time of abandonment to investigate the impact of local disturbance (trampling) on the vegetation and its short-term (< or = 2 year) recovery in a flagship research blanket peatland. Additionally, we examined the effects of local disturbance on fluvial runoff events and the concentrations of dissolved organic carbon (DOC) and particulate organic carbon (POC) in runoff water. Local disturbance heavily impacted peat vegetation, resulting in large areas of scarred and churned peat. Recovery of vascular plants along abandoned tracks was slow, but a functional Sphagnum layer re-established after just one year. The absence of vegetation elicited an increase in the number of runoff events along the tracks, by which POC runoff from the tracks increased. POC concentrations were highest in the surface water from the recently abandoned track, while they were low in the runoff water from the track abandoned longest and the undisturbed control track. We attribute this to the relatively fast recovery of the Sphagnum vegetation. DOC concentrations did not differ significantly either spatially or temporally in surface runoff or soil solution waters. While at an ecosystem scale local disturbances may be negligible in terms of carbon loss, our data points to the need for further research on the potential long-term effects of local disturbance on the vegetation, and significant effects on local scale carbon fluxes. Moreover, the effects of disturbances could be long-lasting and their role on ecosystem processes should not be underestimated. PMID:20692016

  16. Contents of fluorides in vegetables from areas contaminated by industrial emissions: a preliminary report

    SciTech Connect

    Machoy, Z.; Samujlo, D.

    1981-01-01

    In vegetables grown in 1978 and 1979 near a chemical plant where phosphorites and apatites are processed, according to preliminary data, fluoride was significantly elevated in roots of carrots and parsley and in the leaves of parsley.

  17. Discovery and characterization of cryptic endophytes that influence ecological fitness of host vegetation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mechanisms by which seedborne endophytic microbes interact with host plants to influence larger ecological processes are widely unknown. Nonetheless, systems in which endophyte dynamics have been examined suggest high potential to utilize microbes for vegetative restoration. A long term, multidisc...

  18. Investigation of North American vegetation variability under recent climate - A study using the SSiB4/TRIFFID biophysical/dynamic vegetation model

    NASA Astrophysics Data System (ADS)

    Zhang, Z.; Xue, Y.; MacDonald, G. M.; Cox, P. M.; Collatz, G. J.

    2014-12-01

    This study applies a 2-D biophysical model/dynamic vegetation model (SSiB4/TRIFFID) to investigate the dominant factors affecting vegetation equilibrium conditions, to assess the model's ability to simulate seasonal to decadal variability for the past 60 years (from 1948 through 2008), to analyze vegetation spatiotemporal characteristics over North America (NA), and to identify the relationships between vegetation and climate. Satellite data are employed as constraints for this study. The optimum temperature for photosynthesis, leaf drop threshold temperatures, and competition coefficients in the Lotka-Volterra equation have major impact on the vegetation spatial distribution and reach to equilibrium status in SSiB4/TRIFFID. The phenomenon that vegetation competition coefficients affect equilibrium suggests the importance of including biotic effects in dynamical vegetation modeling. SSiB4/TRIFFID can reproduce the features of NA distributions of dominant vegetation types, the vegetation fraction, and LAI, including its seasonal, interannual, and decadal variability, well compared with satellite-derived products. The NA LAI shows an increasing trend after the 1970s in responding to warming. Meanwhile, both simulation and satellite observations reveal LAI increased in the southeastern U.S. starting from the 1980s. The effects of the severe drought during 1987-1992 and the last decade in the southwestern U.S.on vegetation are also evident from the simulated and satellite-derived LAIs.Both simulated and satellite-derived LAIs have the strongest correlations with air temperature at northern middle to high latitudes in spring through their effect on photosynthesis and phenological processes. During the summer, the areas with positive correlations retreat northward. Meanwhile, in southwestern dry lands, the negative correlations appear due to the heat stress there during the summer. Furthermore, there are also positive correlations between soil wetness and LAI, which

  19. Teleconnection between ENSO and Vegetation

    NASA Astrophysics Data System (ADS)

    Kogan, F.

    Since 1980s strong ENSO disturbed weather environment economy and human lives worldwide Total impact of these events on society is estimated in billions of dollars and consequences include famine human health problems loss of life property damage and destruction of the environment Areas sensitive to ENSO have been identified in some world areas from climatic records and recently from 15-year satellite data This presentation examines teleconnection between ENSO and terrestrial ecosystems worldwide using 24-year satellite and in situ data records ENSO events were characterized by monthly sea surface temperature SST anomalies in the tropical Pacific They were collected from the improved SST analysis data set Reynolds and Smith 1994 Average anomalies were calculated for the region 5 r N - 5 r S and 170 r - 120 r E 3 4 area Terrestrial ecosystems were presented by the vegetation health condition indices VHI Kogan 1997 The VHIs derived from AVHRR-based NDVI and 10-11 Phi m thermal radiances were designed to monitor moisture and thermal impacts on vegetation health greenness and vigor Two types of responses were identified In boreal winter ecosystems of northern South America southern Africa and Southeast Asia experienced severe moisture and thermal stress during El Ni n o and favorable conditions during La Ni n a years In central South America and the Horn of Africa regions the response was opposite World ecosystems are less sensitive to SSTs during boreal summer except for the areas in northern Brazil

  20. Satellite remote sensing of vegetation

    NASA Astrophysics Data System (ADS)

    Mahr, Tobias; Peper, Eva; Schubert, Alexander; Warnach, Simon; Pöhler, Denis; Horbanski, Martin; Beirle, Steffen; Mies, Kornelia; Platt, Ulrich; Wagner, Thomas

    2013-04-01

    DOAS (Differential Optical Absorption Spectroscopy) allows to determine the concentration of trace gases based on their specific absorptions cross-sections along a light path. Since 1995, this principle is employed successfully on satellite-based instruments like GOME, GOME-2 and SCIAMACHY for the global measurement of stratospheric and tropospheric trace gases like ozone and nitrogen oxides. Usually, spectral signatures from the ground, where a big part of the sunlight is reflected, are neglected in the evaluation. This can lead to errors in the trace gas determination. However, these structures offer the opportunity to identify surface properties of the earth and different types of vegetation. To analyse spectral reflectance properties, high resolved reflection spectra (FWHM 0.29 nm) from 95 plants were measured between 350 and 1050 nm. They can serve as a basis for the analysis of satellite data. Including different vegetation reference spectra, it is possible to determine groups of plants with similar optical properties. This allows to derive global maps of the spatio-temporal variation of plant distribution by satellite remote sensing. We present first results of this technique based on SCIAMACHY observations.

  1. Fully coupled climate/dynamical vegetation model simulations over Northern Africa during the mid-Holocene

    NASA Astrophysics Data System (ADS)

    Doherty, R.; Kutzbach, J.; Foley, J.; Pollard, D.

    The climate and vegetation patterns of the middle Holocene (6000 years ago; 6ka) over Northern Africa are simulated using a fully-synchronous climate and dynamical vegetation model. The coupled model predicts a northward shift in tropical rainforest and tropical deciduous forest vegetation by about 5 degrees of latitude, and an increase in grassland at the present-day simulated Saharan boundaries. The northward expansion of vegetation over North Africa at 6ka is initiated by an orbitally-induced amplification of the summer monsoon, and enhanced by feedback effects induced by the vegetation. These combined processes lead to a major reduction in Saharan desert area at 6ka relative to present-day of about 50%. However, as shown in previous asynchronous modelling studies, the coupled climate/vegetation model does not fully reproduce the vegetation patterns inferred from palaeoenvironmental records, which suggest that steppe vegetation may have existed across most of Northern Africa. Orbital changes produce an intensification of monsoonal precipitation during the peak rainy season (July to September), whilst vegetation feedbacks, in addition to producing further increases in the peak intensity, play an important role in extending the rainy season from May/June through to November. The orbitally induced increases in precipitation are relatively uniform from west to east, in contrast to vegetation feedback-induced increases in precipitation which are concentrated in western North Africa. Annual-average precipitation increases caused by vegetation feedbacks are simulated to be of similar importance to orbital effects in the west, whilst they are relatively unimportant farther to the east. The orbital, vegetation and combined orbital and vegetation-induced changes in climate, from the simulations presented in this study, have been compared with results from previous modelling studies over the appropriate North African domain. Consequently, the important role of vegetation

  2. Greenland soil bacteria & biogeochemistry: a vegetation cover proxy for climate warming effects

    NASA Astrophysics Data System (ADS)

    Dowdy, K. L.; Sistla, S.; Buckeridge, K. M.; Schimel, J.; Schaeffer, S. M.

    2013-12-01

    Climate warming in the high Arctic is expected to increase plant biomass, deepen thaw, and stimulate decomposition of soil organic matter. However, it remains unclear how warming, plant growth, and microbial processing will interact to drive Arctic carbon and nutrient cycling. For example, greater plant growth should increase carbon storage in the ecosystem; however, increasing plant C inputs and thawing permafrost carbon should stimulate microbial biomass, potentially causing soil respiration to outpace storage. Alternatively, greater plant cover may lower soil temperature through shading, potentially curtailing the predicted increase in microbial activity. To evaluate microbial responses to climate warming in the high Arctic, we characterized the soil bacterial community and related soil biogeochemical properties, including pH, temperature, moisture, bulk density, extractable nutrient pools, extractable organic carbon and nitrogen, and total microbial biomass along a vegetation cover gradient in northwest Greenland. Vegetation cover was classified using the Normalized Difference Vegetation Index (NDVI), and vegetation cover classes were used as a proxy for changes associated with warming. We found that soil moisture increased and soil temperature decreased significantly with vegetation cover; moisture and temperature were higher in organic than in mineral horizons. Extractable nutrients (NO3-, NH4+, PO43-) and extractable organic C and N generally increased with vegetation cover and are higher in organic than in mineral horizons within a given vegetation class, with the exception of NO3-, which was comparable between horizons. Despite increases in available carbon and nutrients, microbial biomass carbon in both horizons ultimately decreased with vegetation cover, as did microbial biomass nitrogen in the mineral horizon. Moreover, the relative proportion of microbial biomass carbon to extractable organic carbon decreased with vegetation cover, indicating that

  3. Wet scrubbing of biomass producer gas tars using vegetable oil

    NASA Astrophysics Data System (ADS)

    Bhoi, Prakashbhai Ramabhai

    experimental data from the wet scrubbing system would be useful in the design and operation of a pilot scale vegetable oil based system. The process model, validated using experimental data, would be a key design tool for the design and optimization of a pilot scale vegetable oil based system.

  4. Wetland vegetation establishment in L-Lake

    SciTech Connect

    Kroeger, S.R.

    1990-07-01

    Wetland vegetation was transplanted from PAR Pond to L-Lake between January and August, 1987. Approximately 100,000 individual plants representing over 40 species were transplanted along the southern shoreline. Three zones of vegetation were created: (1) submersed/floating-leaved, (2) emergent, (3) upper emergent/shrub. During the summers of 1987, 1988, 1989, the Savannah River Ecology Laboratory sampled the vegetation in 54 permanent transects located in planted (N=32) and unplanted areas (N=22). The 1989 vegetation data from L-Lake were compared to 1985 data from PAR Pond.

  5. White Vegetables: Glycemia and Satiety12

    PubMed Central

    Anderson, G. Harvey; Soeandy, Chesarahmia Dojo; Smith, Christopher E.

    2013-01-01

    The objective of this review is to discuss the effect of white vegetable consumption on glycemia, satiety, and food intake. White vegetables is a term used to refer to vegetables that are white or near white in color and include potatoes, cauliflowers, turnips, onions, parsnips, white corn, kohlrabi, and mushrooms (technically fungi but generally considered a vegetable). They vary greatly in their contribution to the energy and nutrient content of the diet and glycemia and satiety. As with other foods, the glycemic effect of many white vegetables has been measured. The results illustrate that interpretation of the semiquantitative comparative ratings of white vegetables as derived by the glycemic index must be context dependent. As illustrated by using the potato as an example, the glycemic index of white vegetables can be misleading if not interpreted in the context of the overall contribution that the white vegetable makes to the carbohydrate and nutrient composition of the diet and their functionality in satiety and metabolic control within usual meals. It is concluded that application of the glycemic index in isolation to judge the role of white vegetables in the diet and, specifically in the case of potato as consumed in ad libitum meals, has led to premature and possibly counterproductive dietary guidance. PMID:23674805

  6. Evaluation of a native vegetation masking technique

    NASA Technical Reports Server (NTRS)

    Kinsler, M. C.

    1984-01-01

    A crop masking technique based on Ashburn's vegetative index (AVI) was used to evaluate native vegetation as an indicator of crop moisture condition. A mask of the range areas (native vegetation) was generated for each of thirteen Great Plains LANDSAT MSS sample segments. These masks were compared to the digitized ground truth and accuracies were computed. An analysis of the types of errors indicates a consistency in errors among the segments. The mask represents a simple quick-look technique for evaluating vegetative cover.

  7. Prevalent vegetation growth enhancement in urban environment.

    PubMed

    Zhao, Shuqing; Liu, Shuguang; Zhou, Decheng

    2016-05-31

    Urbanization, a dominant global demographic trend, leads to various changes in environments (e.g., atmospheric CO2 increase, urban heat island). Cities experience global change decades ahead of other systems so that they are natural laboratories for studying responses of other nonurban biological ecosystems to future global change. However, the impacts of urbanization on vegetation growth are not well understood. Here, we developed a general conceptual framework for quantifying the impacts of urbanization on vegetation growth and applied it in 32 Chinese cities. Results indicated that vegetation growth, as surrogated by satellite-observed vegetation index, decreased along urban intensity across all cities. At the same time, vegetation growth was enhanced at 85% of the places along the intensity gradient, and the relative enhancement increased with urban intensity. This growth enhancement offset about 40% of direct loss of vegetation productivity caused by replacing productive vegetated surfaces with nonproductive impervious surfaces. In light of current and previous field studies, we conclude that vegetation growth enhancement is prevalent in urban settings. Urban environments do provide ideal natural laboratories to observe biological responses to environmental changes that are difficult to mimic in manipulative experiments. However, one should be careful in extrapolating the finding to nonurban environments because urban vegetation is usually intensively managed, and attribution of the responses to diverse driving forces will be challenging but must be pursued. PMID:27185955

  8. Airphoto assessment of changes in aquatic vegetation

    NASA Technical Reports Server (NTRS)

    Markham, B. L.; Philipson, W. R.; Russel, A. E.

    1977-01-01

    Large scale, multiyear, color and color infrared aerial photographs were used to evaluate changes in aquatic vegetation that have accompanied a reduction in phosphorus inputs to a phosphorus-limited, eutrophic lake in New York State. The study showed that the distribution of emergent, floating and submersed vegetation could be determined with little or no concurrent ground data; that various emergent and floating types could be separated and, with limited field checks, identified; and that different submersed types are generally not separable. Major vegetative types are characterized by spectral and nonspectral features, and a classification is developed for compiling time-sequential vegetation maps.

  9. A Comparison of Potential Temperature Variance Budgets over Vegetated and Non-Vegetated Surface

    NASA Astrophysics Data System (ADS)

    Hang, C.; Nadeau, D.; Jensen, D. D.; Pardyjak, E.

    2015-12-01

    Over the past decades, researchers have achieved a fundamental understanding of the budgets of turbulent variables over simplified and (more recently) complex terrain. However, potential temperature variance budgets, parameterized in most meteorological models, are still poorly understood even under relatively idealized conditions. Although each term of the potential temperature variance budget has been studied over different stabilities and surfaces, a detailed understanding of turbulent heat transport over different types of surfaces is still missing. The objectives of this study are thus: 1) to quantify the significant terms in the potential temperature variance budget equation; 2) to show the variability of the budget terms as a function of height and stability; 3) to model the potential temperature variance decay in the late-afternoon and early-evening periods. To do this, we rely on near-surface turbulence observations collected within the Mountain Terrain Atmospheric Modeling and Observations (MATERHORN) program, which was designed to better understand the physics governing processes in mountainous terrain. As part of MATERHORN, large field campaigns were conducted in October 2012 and May 2013 in western Utah. Here, we contrast two field sites: a desert playa (dry lakebed), characterized by a flat surface devoid of vegetation, and a vegetated site, characterized by a low-elevation valley floor covered with greasewood vegetation. As expected, preliminary data analysis reveals that the production and molecular dissipation terms play important roles in the variance budget, however the turbulent transport term is also significant during certain time periods at lower levels (i.e., below 5 m). Our results also show that all three terms decrease with increasing height below 10 m and remain almost constant between 10 m to 25 m, which indicates an extremely shallow surface layer (i.e. 10 m). Further, at all heights and times an imbalance between production and

  10. The Laser Vegetation Imaging Sensor (LVIS): An Airborne Laser Altimeter for Mapping Vegetation and Topography

    NASA Technical Reports Server (NTRS)

    Bryan, J.; Rabine, David L.

    1998-01-01

    The Laser Vegetation Imaging Sensor (LVIS) is an airborne laser altimeter designed to quickly and extensively map surface topography as well as the relative heights of other reflecting surfaces within the laser footprint. Since 1997, this instrument has primarily been used as the airborne simulator for the Vegetation Canopy Lidar (VCL) mission, a spaceborne mission designed to measure tree height, vertical structure and ground topography (including sub-canopy topography). LVIS is capable of operating from 500 m to 10 km above ground level with footprint sizes from 1 to 60 m. Laser footprints can be randomly spaced within the 7 degree telescope field-of-view, constrained only by the operating frequency of the ND:YAG Q-switched laser (500 Hz). A significant innovation of the LVIS altimeter is that all ranging, waveform recording, and range gating are performed using a single digitizer, clock base, and detector. A portion of the outgoing laser pulse is fiber-optically fed into the detector used to collect the return signal and this entire time history of the outgoing and return pulses is digitized at 500 Msamp/sec. The ground return is then located using software digital signal processing, even in the presence of visibly opaque clouds. The surface height distribution of all reflecting surfaces within the laser footprint can be determined, for example, tree height and ground elevation. To date, the LVIS system has been used to monitor topographic change at Long Valley caldera, CA, as part of NASA's Topography and Surface Change program, and to map tree structure and sub-canopy topography at the La Selva Biological Research Station in Costa Rica, as part of the pre-launch calibration activities for the VCL mission. We present results that show the laser altimeter consistently and accurately maps surface topography, including sub-canopy topography, and vegetation height and structure. These results confirm the measurement concept of VCL and highlight the benefits of

  11. Precipitation controls on vegetation phenology in a temperate broadleaf forest estimated from MODIS vegetation index

    NASA Astrophysics Data System (ADS)

    Hwang, T.; Song, C.; Bolstad, P.; Band, L. E.

    2010-12-01

    Forest canopy phenology is an important control of annual water and carbon budgets, and has been shown to respond to regional interannual climate variation. In steep terrain, there are complex spatial variations in phenology in response to well expressed topographic influences on microclimate, community composition, and available soil moisture. We investigate interannual variation in topography-mediated controls on vegetation phenology in a humid temperate broadleaf forest. Moderate-resolution imaging spectro-radiometer (MODIS) vegetation indices are used to derive local patterns of topography-mediated vegetation phenology using a simple post-processing analysis and a non-linear model fitting. Extracted phenological signals show reasonable correlations in terms of both inter-annual variation and inter-site differences with two continuous FPAR measurements from walk-up towers. Combined effects of temperature and orographic precipitation show distinct quadratic responses of senescence timing along elevation gradient, also associated with forest community types. Interannual variation of these quadratic responses is quite related to the amount of precipitation and available soil water (precipitation - potential evapotranspiration) from late summer to fall, which clearly shows precipitation controls on senescence phenology even in a humid temperate broadleaf forest. Normalized plant water stress from continuous soil moisture measurements with TDR sensors also directly supports water stress related controls on senescence phenology. This study also suggests that temperature increases may have less uniform effect on senescence especially in low elevation regions where water availability is also a critical factor for senescence timing. Temperature increases instead may exacerbate plant water stress due to potential evapotranspiration increases, which may increase the degree of dependence of senescence phenology on water availability within the study site. The earlier

  12. [Ecological and food safety considerations about products of vegetable origin].

    PubMed

    Tapia de Daza, M S; Díaz, R V

    1994-12-01

    Media have paid much attention in recent years to emerging microbiological problems in foods of plant origin. The potential for contamination of fruits and vegetables is high because of the wide variety of conditions to which produce is exposed during growth, harvest, processing and distribution. These considerations acquire great significance in the current scenario of the new processing techniques that offer attributes of convenience and fresh-likeness in response to changes in consumption patterns and increased demand of fresh and minimally processed fruits and vegetables. Thus, reliance on low temperature storage and on improved packaging materials/techniques have increased. Even if produce had not been considered a major vector for foodborne diseases, technologies that extend shelf-life by decreasing the rate of product deterioration might increase the risks associated with pathogenic microorganisms, especially of psychotropic nature, by allowing sufficient time for their growth when retarding the development of competitive spoilage organisms. Processing steps that modify the food microenvironment open new possibilities to support pathogens that, for ecological reason, would have never been naturally present in produce. Ecological and safety aspects related to fruits and vegetables as well as foodborne disease outbreaks traceable to produce and reportedly due to Salmonella and Shigella spp., Listeria monocytogenes, Clostridium botulinum, Aeromonas hydrophila, Campylobacter jejuni are reviewed. PMID:8984963

  13. Mapping coastal vegetation, land use and environmental impact from ERTS-1. [Delaware Bay area

    NASA Technical Reports Server (NTRS)

    Klemas, V. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. Vegetation map overlays at a scale of 1:24,000 compiled by multispectral analysis from NASA aircraft imagery for all of Delaware's wetlands are being used as ground truth for ERTS-1 mapping and by state agencies for wetlands management. Six major vegetation species were discriminated and mapped, including percentages of minor species. Analogue enhancements of wetlands vegetation and dredge-fill operations have been produced using General Electric's GEMS data processing and ERTS-1 false color composites. Digital, thematic land use, and vegetation mapping of entire Delaware Bay area is in progress using Bendix Corporation's Earth Resources Data System and ERTS-1 digital tapes. Statistical evaluation of target-group selection reliability has been completed. Three papers have been published on ERTS-1 coastal vegetation and land use. Local and state officials are participating in the ERTS-1 program as co-investigators.

  14. Analysis of the Relationship Between Intra-Urban Vegetation Change and Socio-Economic Data

    NASA Astrophysics Data System (ADS)

    Fonseca, L. M. G.; Boggione, G. A.; Monteiro, A. M. V.; Santos, R.

    2012-07-01

    Understanding the vegetation dynamics in urban areas in both quantitative and qualitative aspects is essential to population welfare and also to economic, social and environmental development. However, it is necessary appropriate tools for monitoring and analysis of the landscape dynamic in a systematic way. Therefore, this study proposes a methodology to analyze the relationship between intra-urban vegetation and the social-economic data using the integrated techniques of remote sensing and GIS as well as data mining. This research intends to answer questions such as: Is it possible to extract the intra-urban vegetation as well as identify the intra-urban vegetation changes from medium spatial resolution images and digital image processing techniques? Is it possible to establish a relationship between the intra-urban vegetation changes and social-economic information using data mining techniques?

  15. Employing lidar to detail vegetation canopy architecture for prediction of aeolian transport

    USGS Publications Warehouse

    Sankey, Joel B.; Law, Darin J.; Breshears, David D.; Munson, Seth M.; Webb, Robert H.

    2013-01-01

    The diverse and fundamental effects that aeolian processes have on the biosphere and geosphere are commonly generated by horizontal sediment transport at the land surface. However, predicting horizontal sediment transport depends on vegetation architecture, which is difficult to quantify in a rapid but accurate manner. We demonstrate an approach to measure vegetation canopy architecture at high resolution using lidar along a gradient of dryland sites ranging from 2% to 73% woody plant canopy cover. Lidar-derived canopy height, distance (gaps) between vegetation elements (e.g., trunks, limbs, leaves), and the distribution of gaps scaled by vegetation height were correlated with canopy cover and highlight potentially improved horizontal dust flux estimation than with cover alone. Employing lidar to estimate detailed vegetation canopy architecture offers promise for improved predictions of horizontal sediment transport across heterogeneous plant assemblages.

  16. Health-promoting components of fruits and vegetables in the diet.

    PubMed

    Liu, Rui Hai

    2013-05-01

    Regular consumption of fruits, vegetables, whole grains, and other plant foods has been negatively correlated with the risk of the development of chronic diseases. There is a huge gap between the average consumption of fruits and vegetables in Americans and the amount recommended by the 2010 Dietary Guidelines for Americans. The key is to encourage consumers to increase the total amount to 9 to 13 servings of fruits and vegetables in all forms available. Fresh, processed fruits and vegetables including frozen and canned, cooked, 100% fruit juices and 100% vegetable juices, as well as dry fruits are all considered as servings of fruits and vegetables per day. A wide variety of fruits, vegetables, whole grains, and other plant foods provide a range of nutrients and different bioactive compounds including phytochemicals, vitamins, minerals, and fibers. Potatoes serve as one of the low-fat foods with unique nutrients and phytochemical profiles, particularly rich in vitamin C, vitamin B-6, potassium, manganese, and dietary fibers. Potatoes provide 25% of vegetable phenolics in the American diet, the largest contributors among the 27 vegetables commonly consumed in the United States, including flavonoids (quercetin and kaempferol), phenolic acids (chlorogenic acid and caffeic acid), and carotenoids (lutein and zeaxanthin). More and more evidence suggests that the health benefits of fruits, vegetables, whole grains, and other plant foods are attributed to the synergy or interactions of bioactive compounds and other nutrients in whole foods. Therefore, consumers should obtain their nutrients, antioxidants, bioactive compounds, and phytochemicals from a balanced diet with a wide variety of fruits, vegetables, whole grains, and other plant foods for optimal nutrition, health, and well-being, not from dietary supplements. PMID:23674808

  17. Cumulative drought and land-use impacts on perennial vegetation across a North American dryland region

    USGS Publications Warehouse

    Munson, Seth M.; Long, A. Lexine; Wallace, Cynthia; Webb, Robert H.

    2016-01-01

    Question The decline and loss of perennial vegetation in dryland ecosystems due to global change pressures can alter ecosystem properties and initiate land degradation processes. We tracked changes of perennial vegetation using remote sensing to address the question of how prolonged drought and land-use intensification have affected perennial vegetation cover across a desert region in the early 21st century? Location Mojave Desert, southeastern California, southern Nevada, southwestern Utah and northwestern Arizona, USA. Methods We coupled the Moderate-Resolution Imaging Spectroradiometer Enhanced Vegetation Index (MODIS-EVI) with ground-based measurements of perennial vegetation cover taken in about 2000 and about 2010. Using the difference between these years, we determined perennial vegetation changes in the early 21st century and related these shifts to climate, soil and landscape properties, and patterns of land use. Results We found a good fit between MODIS-EVI and perennial vegetation cover (2000: R2 = 0.83 and 2010: R2 = 0.74). The southwestern, far southeastern and central Mojave Desert had large declines in perennial vegetation cover in the early 21st century, while the northeastern and southeastern portions of the desert had increases. These changes were explained by 10-yr precipitation anomalies, particularly in the cool season and during extreme dry or wet years. Areas heavily impacted by visitor use or wildfire lost perennial vegetation cover, and vegetation in protected areas increased to a greater degree than in unprotected areas. Conclusions We find that we can extrapolate previously documented declines of perennial plant cover to an entire desert, and demonstrate that prolonged water shortages coupled with land-use intensification create identifiable patterns of vegetation change in dryland regions.

  18. Health-Promoting Components of Fruits and Vegetables in the Diet12

    PubMed Central

    Liu, Rui Hai

    2013-01-01

    Regular consumption of fruits, vegetables, whole grains, and other plant foods has been negatively correlated with the risk of the development of chronic diseases. There is a huge gap between the average consumption of fruits and vegetables in Americans and the amount recommended by the 2010 Dietary Guidelines for Americans. The key is to encourage consumers to increase the total amount to 9 to 13 servings of fruits and vegetables in all forms available. Fresh, processed fruits and vegetables including frozen and canned, cooked, 100% fruit juices and 100% vegetable juices, as well as dry fruits are all considered as servings of fruits and vegetables per day. A wide variety of fruits, vegetables, whole grains, and other plant foods provide a range of nutrients and different bioactive compounds including phytochemicals, vitamins, minerals, and fibers. Potatoes serve as one of the low-fat foods with unique nutrients and phytochemical profiles, particularly rich in vitamin C, vitamin B-6, potassium, manganese, and dietary fibers. Potatoes provide 25% of vegetable phenolics in the American diet, the largest contributors among the 27 vegetables commonly consumed in the United States, including flavonoids (quercetin and kaempferol), phenolic acids (chlorogenic acid and caffeic acid), and carotenoids (lutein and zeaxanthin). More and more evidence suggests that the health benefits of fruits, vegetables, whole grains, and other plant foods are attributed to the synergy or interactions of bioactive compounds and other nutrients in whole foods. Therefore, consumers should obtain their nutrients, antioxidants, bioactive compounds, and phytochemicals from a balanced diet with a wide variety of fruits, vegetables, whole grains, and other plant foods for optimal nutrition, health, and well-being, not from dietary supplements. PMID:23674808

  19. Uncertainty of establishment scheme in the Community Land Model-Dynamic Global Vegetation Model

    NASA Astrophysics Data System (ADS)

    Song, X.; Zeng, X.

    2010-12-01

    Dynamic global vegetation models are very important tools to simulate and predict the relationship between terrestrial ecosystem processes and climate change. They usually consist of several main sub-models, such as establishment, growth, mortality due to stress, competition, reproductive and so forth. In this study, we focus on the establishment sub-model. Establishment sub-model describes the processes of germination of tree seeds and establishment of seedlings. However, due to the complexity of the ecological process and the lack of observation data, current DGVMs use different parameterization schemes of establishment, and the uncertainties of these establishment scheme as well as their impacts on vegetation distribution remain largely unknown. Our work is to introduce several new different establishment schemes, each based on different physical and ecological considerations, into a modified Community Land Model - Dynamic Global Vegetation Model (CLM-DGVM). The sensitivities of the vegetation distribution to different establishment schemes and some essential parameters in the schemes are investigated in different vegetation zones. Our research indicates that establishment scheme has remarkable effects not only on the percent of coverage and population density of different plant functional types (PFTs) but also the community structure such as coexistence of PFTs and even the dominant vegetation. Such changes will alter the ecosystem functioning, and hence have further impacts on climate through the vegetation-atmosphere feedback.

  20. Soil erosion-vegetation interactions in Mediterranean-dry reclaimed mining slopes

    NASA Astrophysics Data System (ADS)

    Moreno de las Heras, Mariano; Merino-Martín, Luis; Espigares, Tíscar; Nicolau, José M.

    2014-05-01

    Mining reclamation in Mediterranean-dry environments represents a complex task. Reclaimed mining slopes are particularly vulnerable to the effects of accelerated soil erosion processes, especially when these processes lead to the formation of rill networks. On the other hand, encouraging early vegetation establishment is perceived as indispensable to reduce the risk of degradation in these man-made ecosystems. This study shows a synthesis of soil erosion-vegetation research conducted in reclaimed mining slopes at El Moral field site (Teruel coalfield, central-east Spain). Our results highlight the role of rill erosion processes in the development of reclaimed ecosystems. Runoff routing is conditioned by the development of rill networks, maximizing the loss of water resources at the slope scale by surface runoff and altering the spatial distribution of soil moisture. As a result, the availability of water resources for plant growth is drastically reduced, affecting vegetation development. Conversely, vegetation exerts a strong effect on soil erosion: erosion rates rapidly decrease with vegetation cover and no significant rill erosion is usually observed after a particular cover threshold is reached. These interactive two-way vegetation-soil erosion relationships are further studied using a novel modeling approach that focuses on stability analysis of water-limited reclaimed slopes. Our framework reproduces two main groups of trends along the temporal evolution of reclaimed slopes: successful trends, characterized by widespread vegetation development and the effective control of rill erosion processes; and gullying trends, characterized by the progressive loss of vegetation and a sharp logistic increase in erosion rates. This stability-analysis also facilitates the determination of threshold values for both vegetation cover and rill erosion that drive the long-term reclamation results, assisting the identification of critical situations that require specific human

  1. Analyzing Groundwater-Vegetation Interactions using a Dynamic Agroecosystem Model

    NASA Astrophysics Data System (ADS)

    Soylu, M. E.; Kucharik, C. J.; Loheide, S. P.

    2012-12-01

    Groundwater is a crucial source of water for vegetation, especially in arid and semiarid environments in many regions around the world and its availability controls the distribution and the physiology of plant species. However, the impact of groundwater on vegetation is not completely understood mainly due to the limited ability of current models to simulate groundwater and vegetation interactions. Existing land surface models (LSM) simulate water and energy fluxes among soil-vegetation-atmosphere systems in a process-based way, but lack a detailed simulation of soil water movement in the unsaturated zone, particularly when groundwater is present. Furthermore, there are only a few available LSM and/or process based vegetation models that can simulate agroecosystems, which are as important to understand as natural ecosystems considering they occupy approximately 40% of the global land surface. On the other hand, current physically-based, variably-saturated soil water flux models are able to accurately simulate water movement in the unsaturated zone. However, they often lack a detailed plant physiology component making it difficult to understand plant responses to both variations in energy fluxes and upward capillary fluxes in shallow groundwater environments. To connect these two different model types, the objectives of this study are (1) to incorporate an advanced dynamic agroecosystem model (Agro-IBIS) and a variably saturated soil water flow model (Hydrus-1D) into a single framework that is capable of simulating groundwater and plant/crop system interactions in a fully, physically-based fashion, and (2) to apply this model using observed climate records to better understand the responses of managed and natural ecosystems to varied water table depths under inter-annual climate forcing conditions. The model results show that as the water table becomes shallower, (1) soil temperature decreases due to the moisture content driven effects on the thermal diffusivity of

  2. Irradiation applications in vegetables and fruits: a review.

    PubMed

    Arvanitoyannis, Ioannis S; Stratakos, Alexandros Ch; Tsarouhas, Panagiotis

    2009-05-01

    There is an increasing trend both in advanced countries and many developing countries to centrally process fresh fruits and vegetables, properly packaged, for distribution and marketing. Irradiation technology proved to be effective in reducing post-harvest losses, and controlling the stored product insects and the microorganisms. Gamma irradiation was employed to restrain potato sprouting and kill pests in grain. Irradiation proved to be extremely beneficial in terms of prolonging the fruit and vegetable shelf life by 3-5 times. In order not to expose fruits and vegetables to high irradiation doses another approach is to use the "hurdle technology," that is to apply more than one technology toward better quality and longer shelf life. This review summarizes a) all the obtained results in this field (either irradiation on its own or in conjunction with other technologies) on fruits and vegetables in 11 figures and eight (8) very comprehensive tables, and b) provides an insight in the various methods (EPR, TL, Comet assay among others) for detection of irradiated foods. PMID:19399670

  3. Application of Machine Learning to the Prediction of Vegetation Health

    NASA Astrophysics Data System (ADS)

    Burchfield, Emily; Nay, John J.; Gilligan, Jonathan

    2016-06-01

    This project applies machine learning techniques to remotely sensed imagery to train and validate predictive models of vegetation health in Bangladesh and Sri Lanka. For both locations, we downloaded and processed eleven years of imagery from multiple MODIS datasets which were combined and transformed into two-dimensional matrices. We applied a gradient boosted machines model to the lagged dataset values to forecast future values of the Enhanced Vegetation Index (EVI). The predictive power of raw spectral data MODIS products were compared across time periods and land use categories. Our models have significantly more predictive power on held-out datasets than a baseline. Though the tool was built to increase capacity to monitor vegetation health in data scarce regions like South Asia, users may include ancillary spatiotemporal datasets relevant to their region of interest to increase predictive power and to facilitate interpretation of model results. The tool can automatically update predictions as new MODIS data is made available by NASA. The tool is particularly well-suited for decision makers interested in understanding and predicting vegetation health dynamics in countries in which environmental data is scarce and cloud cover is a significant concern.

  4. Suspended particle capture by synthetic vegetation in a laboratory flume

    NASA Astrophysics Data System (ADS)

    Fauria, Kristen E.; Kerwin, Rachel E.; Nover, Daniel; Schladow, S. Geoffrey

    2015-11-01

    Vegetated floodplains and wetlands trap particles, a process that is important for water quality and wetland function and morphology. The rates of particle removal by vegetation remain poorly characterized, especially for small particles and vegetation coated with biofilm. In this study, we measured capture rates of road dust by arrays of grass-like synthetic vegetation in a laboratory flume. We performed 40 experiments in which stem density, flow velocity, the presence of biofilm, and initial particle concentration varied, and used an in situ particle size analyzer to measure the concentration of a continuous particle size distribution (1.25-250 µm diameter). We fit first-order decay models to the particle concentration measurements to determine particle capture rates and found that capture rates increased with particle size, stem density, and the presence of biofilm. Capture rates decreased with increasing flow velocity, which suggests that fast flows may resuspend particles from stems. We also calculated percent particle capture efficiencies and fit a new empirical model for capture efficiency to our results. We found that particle capture efficiency was highest for low stem density treatments and propose that stem density affects capture by altering turbulent kinetic energy.

  5. Vegetation and wildfire controls on sediment yield in bedrock landscapes

    NASA Astrophysics Data System (ADS)

    Dibiase, Roman A.; Lamb, Michael P.

    2013-03-01

    rocky landscapes commonly exhibit high sediment yields and are especially sensitive to climate, tectonics, and wildfire. Predicting landscape response to these perturbations demands a quantitative understanding of erosion processes. However, existing models for hillslope sediment production and transport do not apply to landscapes with patchy soil and slopes that exceed the angle for sediment stability. Here we present field measurements in southern California, USA, which indicate that sediment storage on steep slopes is enabled by vegetation that traps sediment upslope. We find that the storage capacity of unburned vegetation dams follows a geometric scaling model with a cubic dependence on effective plant width and an inverse dependence on local slope. Measured sediment volumes behind burned vegetation dams indicate a loss of at least 75% relative to unburned dams, and when expanded to the catchment scale, our measurements match records of postfire sediment yield from nearby retention basins. Contrary to existing models, our observations indicate that wildfire-induced sediment yield is driven by transient storage and release of sediment by vegetation dams, rather than increased bedrock-to-soil conversion rates. Without a feedback between soil production and wildfire, fire may play little role in long-term landscape evolution, and increasing fire frequency in response to climate change may not result in heightened sedimentation hazards due to supply limitations.

  6. RAPID SEPARATION OF ACTINIDES AND RADIOSTRONTIUM IN VEGETATION SAMPLES

    SciTech Connect

    Maxwell, S.

    2010-06-01

    A new rapid method for the determination of actinides and radiostrontium in vegetation samples has been developed at the Savannah River Site Environmental Lab (Aiken, SC, USA) that can be used in emergency response situations or for routine analysis. The actinides in vegetation method utilizes a rapid sodium hydroxide fusion method, a lanthanum fluoride matrix removal step, and a streamlined column separation process with stacked TEVA, TRU and DGA Resin cartridges. Lanthanum was separated rapidly and effectively from Am and Cm on DGA Resin. Alpha emitters are prepared using rare earth microprecipitation for counting by alpha spectrometry. The purified {sup 90}Sr fractions are mounted directly on planchets and counted by gas flow proportional counting. The method showed high chemical recoveries and effective removal of interferences. The actinide and {sup 90}Sr in vegetation sample analysis can be performed in less than 8 h with excellent quality for emergency samples. The rapid fusion technique is a rugged sample digestion method that ensures that any refractory actinide particles or vegetation residue after furnace heating is effectively digested.

  7. General classification handbook for floodplain vegetation in large river systems

    USGS Publications Warehouse

    Dieck, Jennifer J.; Ruhser, Janis; Hoy, Erin E.; Robinson, Larry R.

    2015-01-01

    This handbook describes the General Wetland Vegetation Classification System developed as part of the U.S. Army Corps of Engineers’ Upper Mississippi River Restoration (UMRR) Program, Long Term Resource Monitoring (LTRM) element. The UMRR is a cooperative effort between the U.S. Army Corps of Engineers, U.S. Geological Survey, U.S. Fish and Wildlife Service, and the states of Illinois, Iowa, Minnesota, Missouri, and Wisconsin. The classification system consists of 31 general map classes and has been used to create systemic vegetation data layers throughout the diverse Upper Mississippi River System (UMRS), which includes the commercially navigable reaches of the Mississippi River from Minneapolis, Minnesota, in the north to Cairo, Illinois, in the south, the Illinois River, and navigable portions of the Kaskaskia, Black, St. Croix, and Minnesota Rivers. In addition, this handbook describes the evolution of the General Wetland Vegetation Classification System, discusses the process of creating a vegetation data layer, and describes each of the 31 map classes in detail. The handbook also acts as a pictorial guide to each of the map classes as they may appear in the field, as well as on color-infrared imagery. This version is an update to the original handbook published in 2004.

  8. Isolation and cultivation of the vegetative cells of Porphyra haitanensis

    NASA Astrophysics Data System (ADS)

    Wang, Sujuan; Wang, Guangyuan; Sun, Yunlong; Lu, Anming

    1987-12-01

    This research deals mainly with the use of the vegetative cells of a marine red alga Porphyra haitanensis (laver) as seeds and their culture into young thalli for further cultivation in the sea. The experimental process was as follows. Enzymatically isolated vegetative cells were attached to rope substrates and cultured in the laboratory for a month until they became about 0.2 0.5 cm long sporelings and were then attached (7 15 sporelings per cm of rope) to nets for removal to the open sea for cultivation. A month after culturing, the thalli reached a maximum length of 50 cm (average of 20 30 cm). The thalli grew faster as the water temperature dropped from 21°C to 17°C. It was proved that the vegetative cells isolated from a small thallus about 5 cm long could grow up into normal thalli after being kept frozen for a year. The results of this study show that vegetative cells can be used as new seeds to simplify the production of laver sporelings. This technique is a significant advance in the field of Porphyra culture.

  9. Effect of realistic vegetation variability on seasonal forecasts

    NASA Astrophysics Data System (ADS)

    Catalano, Franco; Alessandri, Andrea; De Felice, Matteo; Doblas-Reyes, Francisco J.

    2014-05-01

    A real predictability hindcast experiment with prescribed Leaf Area Index (LAI) has been performed using the state-of-the-art Earth System Model EC-Earth. LAI input to the climate model has been prescribed using a novel observational dataset based on the third generation GIMMS and MODIS satellite data. The LAI dataset has been pre-processed (monthly averaged, interpolated, gap-filled) to use it in the land surface scheme of EC-Earth (HTESSEL). The vegetation density is modeled by an exponential dependence on LAI, based on the Lambert-Beer formulation. Retrospective hindcasts have been performed with the following model setup: 7 months forecast length, 2 start dates (1st May and 1st November), 10 members, 28 years (1982-2009). Initial conditions were produced at IC3, based on ERA-40/ERA-Interim (atmosphere and land-surface) and NEMOVAR-ORAS4 (ocean and sea-ice) data. Model resolution is T159L62 for the atmosphere and the ORCA1 grid for the ocean. The effect of the realistic LAI prescribed from observation is evaluated with respect to a control experiment where LAI does not vary. Results of the retrospective hindcast experiment demonstrate that a realistic representation of vegetation has a significant effect on evaporation, temperature and precipitation. An improvement of model sensitivity to vegetation variability on the seasonal scale is also evidenced, especially during boreal winter. This may be attributed in particular to the effect of the high vegetation component on the snow cover.

  10. Atmospherically resistant vegetation index (ARVI) for EOS-MODIS

    SciTech Connect

    Kaufman, Y.J.; Tanre, D. )

    1992-03-01

    In this paper atmospherically resistant vegetation index (ARVI) is proposed and developed to be used for remote sensing of vegetation from the earth Observing System (EOS) MODIS sensor. The same index can be used for remote sensing from Landsat TM, and the EOS-HIRIS sensor. The index takes advantage of the presence of the blue channel in the MODIS sensor, in addition to the red and the near IR channels that compose the present normalized difference vegetation index (NDVI). The resistance of the ARVI to atmospheric effects (in comparison to the NDVI) is accomplished by a self-correction process for the atmospheric effect on the red channel, using the difference in the radiance between the blue and the red channels to correct the radiance in the red channel. Simulations using radiative transfer computations on arithmetic and natural surface spectra, for various atmospheric conditions, show that ARVI has a similar dynamic range to the NDVI, but is, on average, four times less sensitive to atmospheric effects that the NDVI. The improvement is much better for vegetated surfaces than for soils. It is much better for moderate to small size aerosol particles (e.g., continental, urban, or smoke aerosol) than for large particle size (e.g., maritime aerosol or dust).

  11. Analysis of vegetable oil production in central Iowa

    SciTech Connect

    Claar, P.W. II.; Colvin, T.S.; Marley, S.J.

    1982-01-01

    Vegetable oil can be used as an emergency substitute for diesel fuel for farming applications. This paper is an economic and energy analysis for vegetable oil production on a 180-ha (450-acre) central Iowa farm. The following data are presented as the basis for the economic analysis: (1) the yields of four varieties of sunflowers at three planting dates; (2) the measured sunflower harvesting losses-preharvest, header, threshing, and separating and cleaning for each variety and date of planting; and (3) the quantities of sunflower oil yielded from the pressing operation. Based on the data presented, it was concluded that even though a farmer could satisfatorily produce sunflowers, the on-farm processed sunflower oil does not compete with current diesel fuel prices. On-farm processed soybean oil has more potential as a substitute fuel from an economic standpoint in central Iowa. 8 tables.

  12. To what extent did changes in July temperature influence Lateglacial vegetation patterns in NW Europe?

    NASA Astrophysics Data System (ADS)

    Birks, Hilary H.; Birks, H. John B.

    2014-12-01

    What was the impact of July temperature changes on vegetation patterns during the Lateglacial period in north-west Europe? Chironomid-inferred mean July air temperature estimates (C-Tjul) are proxy temperature records independent of terrestrial vegetation. The relationships between Lateglacial vegetation inferred from pollen percentages and these temperature estimates are explored using data synthesised geographically from 15 sites where both pollen percentages and C-Tjul are published to assess the influence of temperature and of temperature changes on regional vegetation. Direct impacts of temperature on a species involve passing the range limits or realised niche of that species. The Bølling warming allowed vegetation to develop. The Younger Dryas cooling had direct impacts on species and vegetation types that were at a critical ecotone and thus sensitive to change. Precipitation is extremely important and its interaction with temperature controlled most of the vegetation patterns inferred from these NW European pollen data. High precipitation was important in W Norway, whereas aridity in the YD was a controlling factor in N Norway, the Netherlands, and NE Germany. Under constant climate, ecological processes occurred such as immigration, succession, and soil development that resulted in vegetation changes. Biotic interactions were also important, such as the impact of grazing by mega-herbivores during Allerød time in Ireland that may have restricted the development of birch woodland. At the coarse scale of this synthesis, July temperature alone is seen not to be a good predictor of the patterns of pollen percentages and hence of vegetation through the Lateglacial. Rather, it is the interactions of temperature and precipitation, combined with ecological processes that appear to be the major factors influencing Lateglacial palynological and vegetation patterns in NW Europe.

  13. Role of climate and vegetation density in modulating denudation rates in the Himalaya

    NASA Astrophysics Data System (ADS)

    Olen, Stephanie M.; Bookhagen, Bodo; Strecker, Manfred R.

    2016-07-01

    Vegetation has long been hypothesized to influence the nature and rates of surface processes. We test the possible impact of vegetation and climate on denudation rates at orogen scale by taking advantage of a pronounced along-strike gradient in rainfall and vegetation density in the Himalaya. We combine 12 new 10Be denudation rates from the Sutlej Valley and 123 published denudation rates from fluvially-dominated catchments in the Himalaya with remotely-sensed measures of vegetation density and rainfall metrics, and with tectonic and lithologic constraints. In addition, we perform topographic analyses to assess the contribution of vegetation and climate in modulating denudation rates along strike. We observe variations in denudation rates and the relationship between denudation and topography along strike that are most strongly controlled by local rainfall amount and vegetation density, and cannot be explained by along-strike differences in tectonics or lithology. A W-E along-strike decrease in denudation rate variability positively correlates with the seasonality of vegetation density (R = 0.95, p < 0.05), and negatively correlates with mean vegetation density (R = - 0.84, p < 0.05). Vegetation density modulates the topographic response to changing denudation rates, such that the functional relationship between denudation rate and topographic steepness becomes increasingly linear as vegetation density increases. We suggest that while tectonic processes locally control the pattern of denudation rates across strike of the Himalaya (i.e., S-N), along strike of the orogen (i.e., E-W) climate exerts a measurable influence on how denudation rates scatter around long-term, tectonically-controlled erosion, and on the functional relationship between topography and denudation.

  14. New metrics of affordable nutrition: which vegetables provide most nutrients for least cost?

    PubMed

    Drewnowski, Adam

    2013-09-01

    Measuring food prices per gram, rather than per calorie, is one way to make healthful vegetables appear less expensive. However, a better measure of affordability would take the nutrient content of vegetables into account. This study, based on analyses of US Department of Agriculture datasets, aimed to identify which vegetables, including juices and soups, provided the most nutrients per unit cost. Nutrient density was measured using the Nutrient Rich Foods (NRF) index, based on nine nutrients to encourage: protein; fiber; vitamins A, C, and E; calcium; iron; magnesium; and potassium; and on three nutrients to limit: saturated fat, added sugar, and sodium. Food cost in dollars was calculated per 100 g, per 100 kcal, per serving, and per nutrient content. One-way analyses of variance with post hoc tests were used to determine statistical significance. Results showed that tomato juices and tomato soups, dark green leafy and nonleafy vegetables, and deep yellow vegetables, including sweet potatoes, had the highest NRF scores overall. Highest NRF scores per dollar were obtained for sweet potatoes, white potatoes, tomato juices and tomato soups, carrots, and broccoli. Tomato sauces, raw tomatoes, and potato chips were eaten more frequently than were many other vegetables that were both more affordable and more nutrient-rich. These new measures of affordable nutrition can help foodservice and health professionals identify those vegetables that provide the highest nutrient density per unit cost. Processed vegetables, including soups and juices, can contribute to the quality and the affordability of the diet. PMID:23714199

  15. Factors influencing fruit and vegetable intake among urban Fijians: A qualitative study.

    PubMed

    Morgan, E H; Vatucawaqa, P; Snowdon, W; Worsley, A; Dangour, A D; Lock, K

    2016-06-01

    Low fruit and vegetable intake is an important risk factor for micronutrient deficiencies and non-communicable diseases, but many people worldwide, including most Fijians, eat less than the World Health Organization recommended amount. The present qualitative study explores factors that influence fruit and vegetable intake among 57 urban Fijians (50 women, 7 men) of indigenous Fijian (iTaukei) and South Asian (Indian) descent. Eight focus group discussions were held in and around Suva, Fiji's capital and largest urban area, which explored motivation for eating fruit and vegetables, understandings of links to health and disease, availability and sources, determinants of product choice, and preferred ways of preparing and eating fruit and vegetables. Data were analysed using thematic content analysis. Regardless of ethnicity, participants indicated that they enjoyed and valued eating fruit and vegetables, were aware of the health benefits, and had confidence in their cooking skills. In both cultures, fruit and vegetables were essential components of traditional diets. However, increasing preferences for processed and imported foods, and inconsistent availability and affordability of high-quality, low-priced, fresh produce, were identified as important barriers. The findings indicate that efforts to improve fruit and vegetable intake in urban Fijians should target the stability of the domestic fruit and vegetable supply and access. PMID:26952559

  16. The occurrence of enteric pathogens and Aeromonas species in organic vegetables.

    PubMed

    McMahon, M A; Wilson, I G

    2001-10-22

    A range of commercially available organic vegetables (n = 86) was examined for the presence of Salmonella, Campylobacter, Escherichia coli, E. coli O 157. Listeria and Aeromonas spp., to provide information on the occurrence of such organisms in organic vegetables in Northern Ireland. The study was not designed to quantify such organisms or to compare occurrence with conventionally farmed vegetables. Standard enrichment techniques were used to isolate and identify enteric pathogens and Aeromonas species. No Salmonella, Campylobacter, E. coli. E. coli O 157, Listeria were found in any of the samples examined. Aeromonas species were isolated from 34% of the total number of organic vegetables examined. Many (64%) of the organic vegetables examined were "ready-to-eat" after minimal processing, i.e., washing. Aeromonas spp. was isolated from 41% of these vegetables. Aeromonas spp. was not recovered from certain vegetable types. The most commonly isolated species of Aeromonas was Aeromonas schubertii with 21.0% of all samples contaminated with this species; 5.8% of samples contained A. hydrophila, 5.8% A. trota, 3.5% A. caviae and 2.3% contained A. veronii biovar veronii. Although Aeromonas species are frequently detected in organic vegetables, the absence of accepted enteric pathogens was encouraging, and does not support the allegation of organic foods being of high risk due to the farming methods used. PMID:11759753

  17. Modeling the effect of wave-vegetation interaction on wave setup

    NASA Astrophysics Data System (ADS)

    van Rooijen, A. A.; McCall, R. T.; van Thiel de Vries, J. S. M.; van Dongeren, A. R.; Reniers, A. J. H. M.; Roelvink, J. A.

    2016-06-01

    Aquatic vegetation in the coastal zone attenuates wave energy and reduces the risk of coastal hazards, e.g., flooding. Besides the attenuation of sea-swell waves, vegetation may also affect infragravity-band (IG) waves and wave setup. To date, knowledge on the effect of vegetation on IG waves and wave setup is lacking, while they are potentially important parameters for coastal risk assessment. In this study, the storm impact model XBeach is extended with formulations for attenuation of sea-swell and IG waves, and wave setup effects in two modes: the sea-swell wave phase-resolving (nonhydrostatic) and the phase-averaged (surfbeat) mode. In surfbeat mode, a wave shape model is implemented to capture the effect of nonlinear wave-vegetation interaction processes on wave setup. Both modeling modes are verified using data from two flume experiments with mimic vegetation and show good skill in computing the sea-swell and IG wave transformation, and wave setup. In surfbeat mode, the wave setup prediction greatly improves when using the wave shape model, while in nonhydrostatic mode (nonlinear) intrawave effects are directly accounted for. Subsequently, the model is used for a range of coastal geomorphological configurations by varying bed slope and vegetation extent. The results indicate that the effect of wave-vegetation interaction on wave setup may be relevant for a range of typical coastal geomorphological configurations (e.g., relatively steep to gentle slope coasts fronted by vegetation).

  18. Case Study for EOSDIS Support to MEaSUREs: the Vegetation Index and Vegetation Phenology ESDRs

    NASA Astrophysics Data System (ADS)

    Jenkerson, C.; Meyer, D.; Didan, K.

    2009-12-01

    The United States Geological Survey (USGS) Earth Observation System (EOS) Project (USGS-EOS) managed at the USGS Earth Resources Observation and Science (EROS) Center is a Co-Investigator on the National Aeronautics and Space Administration (NASA) Making Earth System Data Records for Use in Research Environments (MEaSUREs) Cooperative Agreement (CA) #NNX08AT05A. The MEaSUREs CA entitled “Vegetation Phenology and Vegetation Index Products from Multiple Long Term Satellite Data Records” is led by Principal Investigator (PI) Dr. Kamel Didan at the University of Arizona. The goal of the MEaSUREs solicitation is to develop Earth System Data Records (ESDR) which, following evaluation by a NASA Earth Science Data System Working Group (ESDSWG), may be approved as standard NASA Distributed Active Archive Center (DAAC) holdings. USGS-EOS is providing services in the five-year interim to prepare the Vegetation Index and Vegetation Phenology (VIP) ESDRs for transition into the Land Processes DAAC if approved at the end of the term. Pursuing pre-approval support of ESDRs encourages their proper support, usage, and promotes community consensus for these products. USGS-EOS service to the VIP ESDRs includes distribution, user services, outreach support, and metrics reporting. During initial VIP development, USGS-EOS has prototyped a distribution system, the MEaSUREs VIP Client, based on web service functions executing on-demand reformatting, reprojection, and subsetting of native data for delivery as applications-ready products. The client is available as a beta operational access tool for the remainder of the five-year project term. A User Support Model is in place to define the levels of service available through the USGS-EOS to the MEaSUREs VIP community, for the purpose of building product knowledge, client expertise, and familiarity with the user base. USGS-EOS participates in PI-led user workshops by contributing presentation materials that facilitate the promotion

  19. Discoloration of indigo carmine using aqueous extracts from vegetables and vegetable residues as enzyme sources.

    PubMed

    Solís, A; Perea, F; Solís, M; Manjarrez, N; Pérez, H I; Cassani, J

    2013-01-01

    Several vegetables and vegetable residues were used as sources of enzymes capable to discolor indigo carmine (IC), completely or partially. Complete discoloration was achieved with aqueous extracts of green pea seeds and peels of green pea, cucumber, and kohlrabi, as well as spring onion leaves. The source of polyphenol oxidase (PPO), pH, time, and aeration is fundamental for the discoloration process catalyzed by PPO. The PPO present in the aqueous extract of green pea seeds was able to degrade 3,000 ppm of IC at a pH of 7.6 and magnetic stirring at 1,800 rpm in about 36 h. In addition, at 1,800 rpm and a pH of 7.6, this extract discolored 300 ppm of IC in 1:40 h; in the presence of 10% NaCl, the discoloration was complete in 5:50 h, whereas it was completed in 4:30 h with 5% NaCl and 2% laundry soap. PMID:24151588

  20. Discoloration of Indigo Carmine Using Aqueous Extracts from Vegetables and Vegetable Residues as Enzyme Sources

    PubMed Central

    Solís, A.; Perea, F.; Solís, M.; Manjarrez, N.; Pérez, H. I.; Cassani, J.

    2013-01-01

    Several vegetables and vegetable residues were used as sources of enzymes capable to discolor indigo carmine (IC), completely or partially. Complete discoloration was achieved with aqueous extracts of green pea seeds and peels of green pea, cucumber, and kohlrabi, as well as spring onion leaves. The source of polyphenol oxidase (PPO), pH, time, and aeration is fundamental for the discoloration process catalyzed by PPO. The PPO present in the aqueous extract of green pea seeds was able to degrade 3,000 ppm of IC at a pH of 7.6 and magnetic stirring at 1,800 rpm in about 36 h. In addition, at 1,800 rpm and a pH of 7.6, this extract discolored 300 ppm of IC in 1:40 h; in the presence of 10% NaCl, the discoloration was complete in 5:50 h, whereas it was completed in 4:30 h with 5% NaCl and 2% laundry soap. PMID:24151588

  1. Role of extreme events in vegetation dynamics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Extreme climatic events challenge the capacity of vegetation models, including Dynamic Global Vegetation Models, to predict changes in plant species dynamics at local and regional spatial scales and over time periods relevant to ecologists and managers. Extreme climatic events are defined as large,...

  2. 21 CFR 73.260 - Vegetable juice.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Vegetable juice. 73.260 Section 73.260 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.260 Vegetable juice. (a) Identity. (1) The color...

  3. CLIMATE CHANGE AND ISOPRENE EMISSIONS FROM VEGETATION

    EPA Science Inventory

    A global model was developed for estimating spatial and temporal patterns in the emission of isoprene from vegetation under the current climate and used to estimate emissions under doubled-CO2 climate scenarios. urrent emissions were estimated on the basis of vegetation type, fol...

  4. Exploring determinants of vegetable parenting practices

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of this study was to find out if food parenting practices show promise for positively influencing child dietary intake. However, it is unclear what factors motivate parents to engage in vegetable parenting practices. We developed a Model of Goal Directed Vegetable Parenting Practices (MG...

  5. 21 CFR 73.260 - Vegetable juice.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Vegetable juice. 73.260 Section 73.260 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR... coloring foods. (b) Uses and restrictions. Vegetable juice may be safely used for the coloring of...

  6. 21 CFR 73.260 - Vegetable juice.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Vegetable juice. 73.260 Section 73.260 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR... coloring foods. (b) Uses and restrictions. Vegetable juice may be safely used for the coloring of...

  7. 21 CFR 73.260 - Vegetable juice.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Vegetable juice. 73.260 Section 73.260 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR... coloring foods. (b) Uses and restrictions. Vegetable juice may be safely used for the coloring of...

  8. COASTAL SUBMERGED VEGETATION: AQUATIC HABITAT RESEARCH

    EPA Science Inventory

    Aquatic vegetation is one of the most widespread and important types of aquatic habitat, in part because of the exceptional productivity of the plants. Aquatic vegetation also strongly influences local physical and chemical habitat conditions of significance to fish and shellfis...

  9. Microbiological spoilage of fruits and vegetables

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Consumption of fruit and vegetable products has dramatically increased in the U.S. by more than 30% during the past few decades. It is also estimated that about 20% of all fruit and vegetables produced is lost each year due to spoilage. The focus of this chapter is to provide a general background on...

  10. Fuel properties of eleven vegetable oils

    SciTech Connect

    Goering, C.E.; Schwab, A.W.; Daugherty, M.J.; Pryde, E.H.; Keakin, A.J.

    1981-01-01

    Eleven vegetable oils that can be grown as domestic field crops were identified for inclusion in a comparative study. Sample lots of each oil were subjected to ASTM tests appropriate for diesel fuels. The tests identified some problem areas with vegetable oil fuels. The oil samples were also characterized chemically and certain fuel properties were correlated to chemical composition. 10 refs.

  11. Weed Identification and Control in Vegetable Crops.

    ERIC Educational Resources Information Center

    Ferretti, Peter A., Comp.

    This agriculture extension service publication from Pennsylvania State University examines weed control and identification in vegetable crops. Contents include: (1) Types of weeds; (2) Reducing losses caused by weeds, general control methods and home garden weed control; (3) How herbicides are used; (4) Specific weeds in vegetable plantings; and…

  12. Cover crops in vegetable production systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current vegetable production systems require an intensive amount Current vegetable production systems require an intensive amount of work and inputs, and if not properly managed could have detrimental effects on soil and the environment. Practices such as intensive tillage, increased herbicide use, ...

  13. VEGETATION AND POLLEN RELATIONSHIP IN EASTERN CANADA

    EPA Science Inventory

    The relationship between the vegetation and modern pollen assemblages in eastern Canada is summarized and analyzed using isopoll maps, ordination, and cluster analysis. he major vegetation zones recognized in the region are the shrub tundra, forest tundra (divided into shrub and ...

  14. 30 CFR 779.19 - Vegetation information.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... important habitat for fish and wildlife for those species of fish and wildlife identified under 30 CFR 780..., contain a map that delineates existing vegetative types and a description of the plant communities within... information adequate to predict the potential for reestablishing vegetation. (b) When a map or...

  15. Estimating wheat growth with radar vegetation indices

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study, we computed the Radar Vegetation Index (RVI) using observations made with a ground based multi-frequency polarimetric scatterometer system over an entire wheat growth period. The temporal variations of the backscattering coefficients for L-, C-, and X-band, RVI, vegetation water conte...

  16. MODELING STREAM CHANNEL ADJUSTMENT TO WOODY VEGETATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    River restoration and bank stabilization programs often use vegetation for improving stream corridor habitat, aesthetic, and function. Yet no study has examined the use of managed vegetation plantings to transform a straight, degraded stream corridor into a more functional, aesthetically-pleasing m...

  17. The role of vegetation patch spatial configuration in landscape-scale flow-vegetation-sediment feedbacks

    NASA Astrophysics Data System (ADS)

    Larsen, L.; Ma, J.; Kaplan, D. A.

    2015-12-01

    It is becoming increasingly recognized that processes affecting the planform configuration of marshes may be just as important as, if not more important than, vertical accretion and degradation processes. Sea-level rise may erode marshes laterally through wave action or expansion of the tidal channel network just as it may cause vertical inundation. Understanding the feedbacks contingent on the spatial configuration of vegetation patches and microtopography and their interactions with flow is critical to understanding the processes driving marsh persistence and predicting how marshes will respond to changes in environmental drivers. Based on case studies in the Florida Everglades and on generic modeled landscapes, we demonstrate approaches for quantifying spatial configuration and show how they may be used to distinguish between landscapes subject to different driving factors. These approaches include quantifying the connectivity of waterways using the directional connectivity index, quantifying characteristic patch length scales using autocorrelation functions, and state-space reconstruction based on cumulative width of vegetation patches in subsequent downstream cross-sections. Directional connectivity is particularly useful as an indicator of driving mechanisms governing the evolution of marsh landscapes, because connectivity engages directly in feedbacks with landscape-scale flow. We quantified the sensitivity of discharge through a modeled landscape subject to constant-head boundary conditions to different aspects of patch configuration, finding that directional connectivity and landscape fractal dimension were secondary only to patch area. Hence, changes in waterway connectivity caused by inundation (e.g., tidal marshes) or infilling (inland marshes) promote a positive feedback that amplifies the initial change and may contribute substantially to marsh degradation.

  18. Radar response of vegetation: An overview

    NASA Technical Reports Server (NTRS)

    Ulaby, Fawwaz T.; Dobson, M. Craig

    1993-01-01

    This document contains a number of viewgraphs on surface and vegetation backscattering. A classification of vegetation based on general scattering properties is presented. Radar scattering mechanisms are discussed, and backscattering and reflection coefficients for soil back scattering models are given. Radar response to vegetation is presented, with the objectives to discriminate and classify vegetation; to estimate biomass, leaf area index (LAI), and soil moisture; and to monitor changes, including deforestation and growth. Both theory and observation (laboratory, field, air SAR, and European Remote Sensing Satellite (ERS-1) observations) are used to present backscatter coefficients and other data for various vegetation types. ERS-1 results include class statistics, comparison with theory, and biomass response and seasonal variation (LAI) for deciduous and coniferous forests.

  19. Physical modelling of the combined effect of vegetation and wood on river morphology

    NASA Astrophysics Data System (ADS)

    Bertoldi, W.; Welber, M.; Gurnell, A. M.; Mao, L.; Comiti, F.; Tal, M.

    2015-10-01

    The research reported in this paper employs flume experiments to investigate the potential effects of living vegetation and large wood on river morphology, specifically aiming to explore how different wood input and vegetation scenarios impact channel patterns and dynamics. We used a mobile bed laboratory flume, divided into three parallel channels (1.7 m wide, 10 m long) and filled with uniform sand to reproduce braided networks subject to a series of cycles of flooding, wood input, and vegetation growth. Temporal evolution of river configuration (in terms of the braiding index), vegetation establishment and erosion, and wood deposition amount and pattern was recorded in a series of vertical images. The experiments reproduced many forms and processes that have been observed in the field, from scattered logs in unvegetated, dynamic braided channels to large wood jams associated with river bars and bends in vegetated, stable, single-thread rivers. Results showed that the inclusion of vegetation in the experiments changes wood dynamics, in terms of the quantity that is stored and the depositional patterns that develop. Vegetated banks increased channel stability, reducing lateral erosion and the number of active channels. This promoted the formation of stable wood jams, where logs accumulated continuously at the same locations during subsequent floods, reinforcing their effect on river morphology. The feasibility of studying these processes in a controlled environment opens new possibilities for disentangling the complex linkages in the biogeomorphological evolution of the fluvial system and thus for promoting improved scientific understanding.

  20. Predicting Ecologically Important Vegetation Variables from Remotely Sensed Optical/Radar Data Using Neural Networks

    NASA Technical Reports Server (NTRS)

    Kimes, Daniel S.; Nelson, Ross F.

    1998-01-01

    A number of satellite sensor systems will collect large data sets of the Earth's surface during NASA's Earth Observing System (EOS) era. Efforts are being made to develop efficient algorithms that can incorporate a wide variety of spectral data and ancillary data in order to extract vegetation variables required for global and regional studies of ecosystem processes, biosphere-atmosphere interactions, and carbon dynamics. These variables are, for the most part, continuous (e.g. biomass, leaf area index, fraction of vegetation cover, vegetation height, vegetation age, spectral albedo, absorbed photosynthetic active radiation, photosynthetic efficiency, etc.) and estimates may be made using remotely sensed data (e.g. nadir and directional optical wavelengths, multifrequency radar backscatter) and any other readily available ancillary data (e.g., topography, sun angle, ground data, etc.). Using these types of data, neural networks can: 1) provide accurate initial models for extracting vegetation variables when an adequate amount of data is available; 2) provide a performance standard for evaluating existing physically-based models; 3) invert multivariate, physically based models; 4) in a variable selection process, identify those independent variables which best infer the vegetation variable(s) of interest; and 5) incorporate new data sources that would be difficult or impossible to use with conventional techniques. In addition, neural networks employ a more powerful and adaptive nonlinear equation form as compared to traditional linear, index transformations, and simple nonlinear analyses. These neural networks attributes are discussed in the context of the authors' investigations of extracting vegetation variables of ecological interest.