An assessment of plant biointrusion at the Uranium Mill Tailings Remedial Action Project rock-covered disposal cells

International Nuclear Information System (INIS)

1990-10-01

This study is one of a number of special studies that have been conducted regarding various aspects of the Uranium Mill Tailings Remedial Action (UMTRA) Project. This special study was proposed following routine surveillance and maintenance surveys and observations reported in a special study of vegetative covers (DOE, 1988), in which plants were observed growing up through the rock erosion layer at recently completed disposal cells. Some of the plants observed were deep-rooted woody species, and questions concerning root intrusion into disposal cells and the need to control plant growth were raised. The special study discussed in this report was designed to address some of the ramifications of plant growth on disposal cells that have rock covers. The NRC has chosen rock covers over vegetative covers in the arid western United States because licenses cannot substantiate that the vegetative covers ''will be significantly greater than 30 percent and preferably 70 percent,'' which is the amount of ''vegetation required to reduce flow to a point of stability.'' The potential impacts of vegetation growing in rock covers are not addressed by the NRC (1990). The objectives, then, of this study were to determine the species of plants growing on two rock-covered disposal cells, study the rooting pattern of plants on these cells, and identify possible impacts of plant root penetration on these and other UMTRA Project rock-covered cells

Predicting the presence and cover of management relevant invasive plant species on protected areas.

Science.gov (United States)

Iacona, Gwenllian; Price, Franklin D; Armsworth, Paul R

2016-01-15

Invasive species are a management concern on protected areas worldwide. Conservation managers need to predict infestations of invasive plants they aim to treat if they want to plan for long term management. Many studies predict the presence of invasive species, but predictions of cover are more relevant for management. Here we examined how predictors of invasive plant presence and cover differ across species that vary in their management priority. To do so, we used data on management effort and cover of invasive plant species on central Florida protected areas. Using a zero-inflated multiple regression framework, we showed that protected area features can predict the presence and cover of the focal species but the same features rarely explain both. There were several predictors of either presence or cover that were important across multiple species. Protected areas with three days of frost per year or fewer were more likely to have occurrences of four of the six focal species. When invasive plants were present, their proportional cover was greater on small preserves for all species, and varied with surrounding household density for three species. None of the predictive features were clearly related to whether species were prioritized for management or not. Our results suggest that predictors of cover and presence can differ both within and across species but do not covary with management priority. We conclude that conservation managers need to select predictors of invasion with care as species identity can determine the relationship between predictors of presence and the more management relevant predictors of cover. Copyright © 2015 Elsevier Ltd. All rights reserved.

Screening of plant species as ground cover on uranium mill tailings

International Nuclear Information System (INIS)

Venu Babu, P.; Eapen, S.

2012-01-01

The concept of construction of dams or holding areas for uranium mill tailings is relatively new in India and to date there is only one such facility being maintained by Uranium Corporation of India Limited (UCIL) at Jaduguda in Jharkhand. Due to the residual nature of radionuclides, chiefly uranium and its daughter products, special emphasis is given to the engineering aspects of the mill tailings ponds so as to ensure safety to general public for at least 200 years. Once a mill tailings pond reaches to its full capacity, creation of barrier layers over the mill tailings to prevent seepage of rain water and also erosion of mill tailings due to wind and water are advocated and a number of procedures are followed worldwide. Taking the extraordinary period of public safety to be assured, providing soil covers along with contouring and appropriate slopes over which vegetation is grown is gaining popularity. The vegetation not only reduces the impact of rain water hitting the soil cover, thereby reducing the soil erosion, but also lowers the moisture in the soil cover by extensive evapotranspiration, ensuring long term hydrological separation of the mill tailings underneath. Based on set criteria, applicable to the field scenario of mill tailings, a screening experiment was conducted under pot culture conditions to evaluate the survival and growth of different plant species. The plants after germination and hardening were transplanted into beakers containing mill tailings and periodical measurements on appropriate morphological characteristics such as plant height, length of twiners, number of tillers and number of leaves were recorded and evaluated. Of the twenty species tested in mill tailings, significant differences were noticed in the vigour of growth and several plant species could indeed establish well completing their life cycle including flowering and seed setting. Further, several leguminous species could also produce root nodules. It appears that the

Effect of plant cover on presence of Black Francolin (Francolinus ...

African Journals Online (AJOL)

STORAGESEVER

2010-06-21

Jun 21, 2010 ... factors threatening the populations of these birds in Khouzestan Province, southwestern Iran. Using plot sampling ... Key words: Black francolin, Francolinus francolinus, plant cover, habitat, Iran. INTRODUCTION ... to get food.

40 CFR 63.1562 - What parts of my plant are covered by this subpart?

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 12 2010-07-01 2010-07-01 true What parts of my plant are covered by... What parts of my plant are covered by this subpart? (a) This subpart applies to each new, reconstructed...-regenerative, cyclic, or continuous processes) that are associated with regeneration of the catalyst used in...

Total Logistic Plant Solutions

Directory of Open Access Journals (Sweden)

Dusan Dorcak

2016-02-01

Full Text Available The Total Logistics Plant Solutions, plant logistics system - TLPS, based on the philosophy of advanced control processes enables complex coordination of business processes and flows and the management and scheduling of production in the appropriate production plans and planning periods. Main attributes of TLPS is to create a comprehensive, multi-level, enterprise logistics information system, with a certain degree of intelligence, which accepts the latest science and research results in the field of production technology and logistics. Logistic model of company understands as a system of mutually transforming flows of materials, energy, information, finance, which is realized by chain activities and operations

Mycotoxicogenic fungal inhibition by innovative cheese cover with aromatic plants.

Science.gov (United States)

Moro, Armando; Librán, Celia M; Berruga, M Isabel; Zalacain, Amaya; Carmona, Manuel

2013-03-30

The use of aromatic plants and their extracts with antimicrobial properties may be compromised in the case of cheese, as some type of fungal starter is needed during its production. Penicillium verrucosum is considered a common cheese spoiler. The aim of this study was to evaluate the innovative use of certain aromatic plants as natural cheese covers in order to prevent mycotoxicogenic fungal growth (P. verrucosum). A collection of 12 essential oils (EOs) was obtained from various aromatic plants by solvent-free microwave extraction technology, and volatile characterisation of the EOs was carried out by gas chromatography/mass spectrometry. The most effective EOs against P. verrucosum were obtained from Anethum graveolens, Hyssopus officinalis and Chamaemelum nobile, yielding 50% inhibition of fungal growth at concentration values lower than 0.02 µL mL⁻¹. All EOs showed high volatile heterogeneity, with α-phellandrene, pinocamphone, isopinocamphone, α-pinene, camphene, 1,8-cineole, carvacrol and trans-anethole being found to be statistically significant in the antifungal model. The use of these aromatic plants as natural covers on cheese can satisfactorily inhibit the growth of some mycotoxicogenic fungal spoilers. Among the volatile compounds present, α- and β-phellandrene were confirmed as the most relevant in the inhibition. © 2012 Society of Chemical Industry.

Total phenolics and total flavonoids in selected Indian medicinal plants.

Science.gov (United States)

Sulaiman, C T; Balachandran, Indira

2012-05-01

Plant phenolics and flavonoids have a powerful biological activity, which outlines the necessity of their determination. The phenolics and flavonoids content of 20 medicinal plants were determined in the present investigation. The phenolic content was determined by using Folin-Ciocalteu assay. The total flavonoids were measured spectrophotometrically by using the aluminium chloride colorimetric assay. The results showed that the family Mimosaceae is the richest source of phenolics, (Acacia nilotica: 80.63 mg gallic acid equivalents, Acacia catechu 78.12 mg gallic acid equivalents, Albizia lebbeck 66.23 mg gallic acid equivalents). The highest total flavonoid content was revealed in Senna tora which belongs to the family Caesalpiniaceae. The present study also shows the ratio of flavonoids to the phenolics in each sample for their specificity.

Impact of the construction of a hydroelectric power plant on the land cover and use: study of the basin Lajeado Bonito - RS

International Nuclear Information System (INIS)

Tramontina, Juliana; Breunig, Fabio Marcelo

2015-01-01

This work aims to analyze the impact of the construction of a hydroelectric power plant on land cover and use in Lajeado Bonito-RS watershed. The study evaluated the temporal evolution of land cover and use in the watershed for the period before and after to installation of hydroelectric plant Foz do Chapeco (2009 to 2010). For temporal analysis, two images were interpreted, one orbital image of High Resolution Camera (HRC) onboard of the CBERS-2B, acquired in December 29, 2009. And a high-resolution image obtained from Google Earth application, acquired at December 26, 2010. The land cover and use maps were generated by vector editing SPRING software. We found that the predominant land use related to agriculture and livestock, including bare soil. In 2009 this class accounted for 70.23% of the total area, while it come to represent 61.8% in 2010. At the same time, there was increase of areas with native forest cover, from 27.49% covered by forest in 2009, to 31% in 2010. The results showed that in both 2009 and 2010 years, approximately 49% of permanent preservation area were used inappropriately. (author)

Specific 137Cs and 90Sr accumulation in living soil cover plants of forest cenoses

International Nuclear Information System (INIS)

Ermakova, O.O.; Kuz'mich, O.T.; Kazej, A.P.

2000-01-01

Observations of the radionuclide content in 38 species of living soil cover plants were carried out in Pinetum myrtillosum, pleuroziosum; Quercetum pteridiosum; Betuletum myrtillosum; Glutinoso-Alnetum filipendulosum, Glutinoso-Alnetum. Radiological monitoring for the 137 Cs and 90 Sr content in living cover plants of forest cenosis in Belarus allows 137 Cs and 90 Sr accumulation to be predicted for the plants of lower circles of forest cenosis. a obtained one can notice that the radionuclide accumulation intensity depends on the contamination density of the accumulation soil layer, forest growing conditions, species and first of all on the weather conditions of the year of observation. Unfavourable conditions (drought) lead to an increase in 137 Cs accumulation by a factor of 3-5 depending on the plant species. The maximum values was obtained in ferns which grow under all the controlled forest growing conditions. The species specific character of 137 Cs and 90 Sr accumulation is due to their ecological-physiological peculiarities. The relationship was found between the caesium-137 accumulation and macro element quantity in overground organs of living soil cover plants. (authors)

Effect of repeated mowing to reduce graminoid plant cover on the moss carpet at a Sphagnum farm in North America

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M. Guêné-Nanchen

2017-09-01

Full Text Available Sphagnum farming is defined as the sustainable production of non-decomposed Sphagnum biomass on a cyclical and renewable basis. In this article, the influence and necessity of mowing graminoid plants to optimise Sphagnum growth in Sphagnum farming basins are examined. Repeated mowing was applied to reduce graminoid plant cover at two different stages of the production cycle (one-year-old and seven-year-old Sphagnum moss carpet at the beginning of the experiment at an experimental Sphagnum farm in eastern Canada. Sphagnum growth (cover, biomass, moss layer thickness was measured after three years of mowing. In addition, a greenhouse experiment was carried out to determine whether there is a threshold for graminoid plant cover beyond which mowing becomes necessary. Sphagnum cover and biomass were not affected by repeated mowing, even if mowing reduced the cover of graminoid plants. Thus, it appears that mowing is unnecessary if the dominant vascular species is a graminoid plant such as Eriophorum angustifolium, which accumulates minimal amounts of litter. Furthermore, high cover of Eriophorum angustifolium (up to 85 % did not affect Sphagnum cover in a density-controlled greenhouse experiment. When the specific goal is Sphagnum fibre production, decisions about control of graminoid plants should be made after considering the cover, life form and litter accumulation potentials of the dominant graminoid species involved.

Plant species potentially suitable for cover on low-level solid nuclear waste disposal sites: a literature review

Energy Technology Data Exchange (ETDEWEB)

Brenkert, A.L.; Parr, P.D.; Taylor, F.G.

1984-09-01

This report reviews available literature on soil conditions, hydrology, and climatological data and suggests plant species suitable for covering the low-level nuclear waste disposal areas in the White Oak Creek Watershed within the Oak Ridge Reservation. Literature on naturally invading species and secondary succession, on plant species used for reclamation of coal spoils and roadsides, and on horticultural species is reviewed. The potential of plant species to take up, or mine, the waste through deep rooting is assessed. The effects of vegetation cover on the water balance in a watershed are reviewed. Several conclusions are presented concerning the management of vegetation cover on low-level solid waste disposal areas. 163 references, 2 figures, 9 tables.

Plant species potentially suitable for cover on low-level solid nuclear waste disposal sites: a literature review

International Nuclear Information System (INIS)

Brenkert, A.L.; Parr, P.D.; Taylor, F.G.

1984-09-01

This report reviews available literature on soil conditions, hydrology, and climatological data and suggests plant species suitable for covering the low-level nuclear waste disposal areas in the White Oak Creek Watershed within the Oak Ridge Reservation. Literature on naturally invading species and secondary succession, on plant species used for reclamation of coal spoils and roadsides, and on horticultural species is reviewed. The potential of plant species to take up, or mine, the waste through deep rooting is assessed. The effects of vegetation cover on the water balance in a watershed are reviewed. Several conclusions are presented concerning the management of vegetation cover on low-level solid waste disposal areas. 163 references, 2 figures, 9 tables

No-till Organic Soybean Production Following a Fall-planted Rye Cover Crop

OpenAIRE

Porter, Paul; Feyereisen, Gary; De Bruin, Jason; Johnson, Gregg

2005-01-01

The conventional corn-soybean rotation in the United States (USA) is a leaky system with respect to nitrate-nitrogen (nitrate-N), in part because these crops grow only five months of the year. Ecosystem functioning can be improved with the use of an appropriate fall-planted cover crop, but this practice is not common. Organic soybean production in the USA typically relies on delayed planting, crop rotation, intensive harrowing and interrow cultivation for weed control. Research on timing of ...

Plant cover effect on Bolson tortoise (Gopherus flavomarginatus Legler 1959, Testudinidae burrow use

Directory of Open Access Journals (Sweden)

Jorge Luis Becerra-López

2017-03-01

Full Text Available The Bolson tortoise, Gopherus flavomarginatus, occurs within a restricted geographical area in the Mexican Chihuahuan Desert. We analyzed the variation in surface microhabitat with relation to the burrow occupancy for this tortoise at the Mapimí Biosphere Reserve, Mexico. In summer 2010, we monitored burrow activity (active, inactive, or abandoned and measured environmental factors that might influence the burrow’s occupancy by tortoises (air temperature, relative humidity and substrate temperature, both inside and outside the burrow, and the plant cover around it. Discriminant analysis was used to identify the importance of these variables influencing burrow occupancy. Correlation and linear regression analyses were performed to quantify the relation between environmental factors in the sampled burrows. Results. Sixty-one burrows were identified at the Tortugas locality. The first function’s auto-value analysis indicates that this function explains 97.9% of the variation in burrow activity status; high occupancy scores were associated with low substrate temperature inside the burrow. Plant cover was inversely proportional to substrate temperature inside the burrow. These results suggest the importance the density of plants surrounding the tortoise’s burrow as a key factor influencing the burrow microclimate and occupancy by the tortoises. Conclusions. Gopherus flavomarginatus inhabits burrows, in part, based on microhabitat structure, with plant cover being a main factor influencing burrow occupancy. Our findings indicate that human land use and vegetation management are important for conserving Bolson tortoises, and for understanding habitat conditions necessary for the successful establishment of populations elsewhere.

Predicting plant diversity patterns in Madagascar: understanding the effects of climate and land cover change in a biodiversity hotspot.

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Kerry A Brown

Full Text Available Climate and land cover change are driving a major reorganization of terrestrial biotic communities in tropical ecosystems. In an effort to understand how biodiversity patterns in the tropics will respond to individual and combined effects of these two drivers of environmental change, we use species distribution models (SDMs calibrated for recent climate and land cover variables and projected to future scenarios to predict changes in diversity patterns in Madagascar. We collected occurrence records for 828 plant genera and 2186 plant species. We developed three scenarios, (i.e., climate only, land cover only and combined climate-land cover based on recent and future climate and land cover variables. We used this modelling framework to investigate how the impacts of changes to climate and land cover influenced biodiversity across ecoregions and elevation bands. There were large-scale climate- and land cover-driven changes in plant biodiversity across Madagascar, including both losses and gains in diversity. The sharpest declines in biodiversity were projected for the eastern escarpment and high elevation ecosystems. Sharp declines in diversity were driven by the combined climate-land cover scenarios; however, there were subtle, region-specific differences in model outputs for each scenario, where certain regions experienced relatively higher species loss under climate or land cover only models. We strongly caution that predicted future gains in plant diversity will depend on the development and maintenance of dispersal pathways that connect current and future suitable habitats. The forecast for Madagascar's plant diversity in the face of future environmental change is worrying: regional diversity will continue to decrease in response to the combined effects of climate and land cover change, with habitats such as ericoid thickets and eastern lowland and sub-humid forests particularly vulnerable into the future.

Establishment of five cover crops and total soil nutrient extraction in a humid tropical soil in the Peruvian Amazon

Science.gov (United States)

In order to evaluate the establishment of five cover crops and their potential to increase soil fertility through nutrient extraction, an experiment was installed in the Research Station of Choclino, San Martin, Peru. Five cover crops were planted: Arachis pintoi Krapov. & W.C. Greg, Calopogonium m...

EFFECT OF COVER CROPS ON SOIL ATTRIBUTES, PLANT NUTRITION, AND IRRIGATED TROPICAL RICE YIELD

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ANDRE FROES DE BORJA REIS

2017-01-01

Full Text Available In flood plains, cover crops are able to alter soil properties and significantly affect rice nutrition and yield. The aims of this study were to determine soil properties, plant nutrition, and yield of tropical rice cultivated on flood plains after cover crop cultivation with conventional tillage (CT and no-tillage system (NTS at low and high nitrogen (N fertilization levels. The experimental design was a randomized block in a split-split-plot scheme with four replications. In the main plots were cover crops sunhemp (Crotalaria juncea and C. spectabilis, velvet bean (Mucuna aterrima, jackbean (Canavalia ensiformis, pigeon pea (Cajanus cajan, Japanese radish (Raphanus sativus, cowpea (Vigna unguiculata and a fallow field. In the subplots were the tillage systems (CT or NTS. The nitrogen fertilization levels in the sub-subplots were (10 kg N ha-1 and 45 kg N ha-1. All cover crops except Japanese radish significantly increased mineral soil nitrogen and nitrate concentrations. Sunhemp, velvet bean, and cowpea significantly increased soil ammonium content. The NTS provides higher mineral nitrogen and ammonium content than that by CT. Overall, cover crops provided higher levels of nutrients to rice plants in NTS than in CT. Cover crops provide greater yield than fallow treatments. Rice yield was higher in NTS than in CT, and greater at a higher rather than lower nitrogen fertilization level.

Impact of plant cover on fitness and behavioural traits of captive red-eyed tree frogs (Agalychnis callidryas.

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Christopher J Michaels

Full Text Available Despite the importance of ex situ conservation programmes as highlighted in the Amphibian Conservation Action Plan, there are few empirical studies that examine the influence of captive conditions on the fitness of amphibians, even for basic components of enclosure design such as cover provision. Maintaining the fitness of captive amphibian populations is essential to the success of ex situ conservation projects. Here we examined the impact of plant cover on measures of fitness and behaviour in captive red-eyed tree frogs (Agalychnis callidryas. We found significant effects of plant provision on body size, growth rates and cutaneous bacterial communities that together demonstrate a compelling fitness benefit from cover provision. We also demonstrate a strong behavioural preference for planted rather than non-planted areas. We also assessed the impact of plant provision on the abiotic environment in the enclosure as a potential driver of these behavioural and fitness effects. Together this data provides valuable information regarding enclosure design for a non-model amphibian species and has implications for amphibian populations maintained in captivity for conservation breeding programmes and research.

Effects of plant cover on soil N mineralization during the growing season in a sandy soil

Science.gov (United States)

Yao, Y.; Shao, M.; Wei, X.; Fu, X.

2017-12-01

Soil nitrogen (N) mineralization and its availability plays a vital role in regulating ecosystem productivity and C cycling, particularly in semiarid and desertified ecosystems. To determine the effect of plant cover on N turnover in a sandy soil ecosystem, we measured soil N mineralization and inorganic N pools in soil solution during growing season in a sandy soil covered with various plant species (Artemisia desertorum, Salix psammophila, and Caragana korshinskii). A bare sandy soil without any plant was selected as control. Inorganic N pools and N mineralization rates decreased overtime during the growing season, and were not affected by soil depth in bare land soils, but were significantly higher at the 0-10 cm layer than those at the 10-20 cm soil layer under any plant species. Soil inorganic N pool was dominated by ammonium, and N mineralization was dominated by nitrification regardless of soil depth and plant cover. Soils under C. korshinskii have significant higher inorganic N pools and N mineralization rate than soils under bare land and A. desertorum and S. psammophila, and the effects of plant cover were greater at the 0-10 cm soil layer than at the 10-20 cm layer. The effects of C. korshinskii on soil inorganic N pools and mineralization rate varied with the stage of growing season, with greater effects on N pools in the middle growing season, and greater effects on mineralization rate at the last half of the growing season. The results from this study indicate that introduction of C. korshinskii has the potential to increase soil N turnover and availability in sandy soils, and thus to decrease N limitation. Caragana korshinskii is therefore recommend for the remediation of the desertified land.

PERFORMANCE OF ‘NANICÃO JANGADA’ BANANA PLANTS INTERCROPPED WITH WINTER COVER CROPS

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RICARDO SFEIR DE AGUIAR

Full Text Available ABSTRACT The use of cover crops species may be an important strategy in the pursuit of sustainability of agroecosystems, considering benefits to soil, such as improvements of physical and chemical characteristics, and weed control. The objective of this study was to evaluate the effect of winter cover crops and other soil managements on chemical soil properties, on the cycle, on the production of the first cycle and on the fruit quality of banana cv. Nanicão Jangada in Andirá – PR, Brazil. The experiment was carried out in a commercial. Planting of banana suckers from the grower area occurred in the first half of March 2011, with a spacing of 2.40 m between rows and 1.90 m between plants. The experiment was designed in randomized blocks with four replications and six plants per plot. The six treatments were: black oat (Avenastrigosa Schreb, forage turnip (Raphanus sativus L. var. oleiferus, consortium of black oat and forage turnip, chicken litter, residues of banana plants, and bare ground. The evaluations were vegetative development and life cycle of banana plants, yield and quality of fruits, soil chemical characterstics, and fresh and dry mass of green manures. The results were submitted to ANOVA (F Test, and Tukey test at 5 % probability. Black oat and black oat with forage turnip consortium were superior in biomass production. Systems of soil management had no effect on the variables, except in the periods between planting and flowering and between planting and harvest, which were shorter in the treatment of soil management with crop residues, longer in the treatment with forage turnip, and intermediate in the other treatments.

Forms of phosphorus in an oxisol under different soil tillage systems and cover plants in rotation with maize

Directory of Open Access Journals (Sweden)

Arminda Moreira de Carvalho

2014-06-01

Full Text Available Phosphorus fractions play a key role in sustaining the productivity of acid-savanna Oxisols and are influenced by tillage practices. The aim of this study was to quantify different P forms in an Oxisol (Latossolo Vermelho-Amarelo from the central savanna region of Brazil under management systems with cover crops in maize rotation. Three cover crops (Canavalia brasiliensis, Cajanus cajan (L., and Raphanus sativus L. were investigated in maize rotation systems. These cover crops were compared to spontaneous vegetation. The inorganic forms NaHCO3-iP and NaOH-iP represented more than half of the total P in the samples collected at the depth of 5-10 cm during the rainy season when the maize was grown. The concentration of inorganic P of greater availability (NaHCO3-iP and NaOH-iP was higher in the soil under no-tillage at the depth of 5-10 cm during the rainy season. Concentrations of organic P were higher during the dry season, when the cover crops were grown. At the dry season, organic P constituted 70 % of the labile P in the soil planted to C. cajan under no-tillage. The cover crops were able to maintain larger fractions of P available to the maize, resulting in reduced P losses to the unavailable pools, mainly in no-tillage systems.

Implications of plant cover in the structure of a clayey oxisol under ...

African Journals Online (AJOL)

Knowledge of indicators of soil physical quality is of paramount importance for better understanding of soil-plant relationships. These indicators include the bulk density and soil resistance to penetration. The objective of this study was to evaluate the use of four cover crop species in the process of reducing the soil density ...

[Litter decomposition and soil faunal diversity of two understory plant debris in the alpine timberline ecotone of western Sichuan in a snow cover season].

Science.gov (United States)

He, Run-lian; Chen, Ya-mei; Deng, Chang-chun; Yan, Wan-qin; Zhang, Jian; Liu, Yang

2015-03-01

In order to understand the relationship between litter decomposition and soil fauna diversity during snow cover season, litterbags with plant debris of Actinothuidium hookeri, Cystopteris montana, two representative understory plants in the alpine timberline ecotone, and their mixed litter were incubated in the dark coniferous forest, timberline and alpine meadow, respectively. After a snow cover season, the mass loss and soil fauna in litterbags were investigated. After decomposition with a snow cover season, alpine meadow showed the highest mass loss of plant debris in comparison with coniferous forest and timberline, and the mass loss of A. hookeri was more significant. The mixture of two plants debris accelerated the mass loss, especially in the timberline. A total of 968 soil invertebrates, which belonged to 5 classes, 10 orders and 35 families, were captured in litterbags. Acarina and Collembola were the dominant groups in plant debris. The numbers of individuals and groups of soil faunal communities in litter of timberline were higher than those of alpine meadow and dark coniferous forest. Canonical correspondence analysis (CCA) indicated that the groups of soil animals were related closely with the average temperature, and endemic species such as Isoptera and Geophilomorpha were observed only in coniferous forest, while Hemiptera and Psocoptera only in.the alpine meadow. The diversity of soil faunal community was more affected by plant debris varieties in the timberline than in the coniferous forest and alpine meadow. Multiple regression analysis indicated that the average temperature and snow depth explained 30.8% of the variation of litter mass loss rate, soil animals explained 8.3%, and altogether explained 34.1%. Snow was one of the most critical factors impacting the decomposition of A. hookeri and C. montana debris in the alpine timberline ecotone.

Incidence of plant cover over the autotrophic nitrifying bacteria population in a fragment of Andean forest

International Nuclear Information System (INIS)

Gonzalez, Xiomara; Gonzalez, L; Varela, A; Ahumada, J A

1999-01-01

It was determined the incidence of plant cover (forest vs. pasture), on the autotrophy nitrifying bacteria, through the effect of biotic factors (radical exudate) and abiotic factors (temperature, ph and humidity), in a high mountain cloud forest fragment. The site of study was located near La Mesa (Cundinamarca) municipality. The temperature of soil was measured in situ, and soil samples were collected and carried to the laboratory for pH and humidity percentage measurements. Serial soil dilution method was used for plating samples on a selective culture medium with ammonium sulphate as nitrogen source, in order to estimate the autotrophic nitrifying bacteria population levels. Grown colonies were examined macro and microscopically. The quantity of nitrates produced by bacteria cultured in vitro was determined spectra-photometrical. In relation to the abiotic factors, there was no significant differences of pH between both plant covers, but there were significant for soil humidity and temperature (p<0.05). There were highly significant differences with respect to the bacteria population levels (p<0.0001) and with respect to nitrate production. This suggests a higher bacterial activity in the under forest cover. The radical exudate from both types of plant cover reduced the viability of bacteria in vitro, from 1:1 to 1:30 exudate bacteria proportions. In the soils physical and chemical analysis, it was found a higher P and Al concentrations, and a higher CIC and organic matter content under the forest cover. It is suggested the importance of this functional group in this ecosystem

Influence of Seeding Ratio, Planting Date, and Termination Date on Rye-Hairy Vetch Cover Crop Mixture Performance under Organic Management.

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Andrew Lawson

Full Text Available Cover crop benefits include nitrogen accumulation and retention, weed suppression, organic matter maintenance, and reduced erosion. Organic farmers need region-specific information on winter cover crop performance to effectively integrate cover crops into their crop rotations. Our research objective was to compare cover crop seeding mixtures, planting dates, and termination dates on performance of rye (Secale cereale L. and hairy vetch (Vicia villosa Roth monocultures and mixtures in the maritime Pacific Northwest USA. The study included four seed mixtures (100% hairy vetch, 25% rye-75% hairy vetch, 50% rye-50% hairy vetch, and 100% rye by seed weight, two planting dates, and two termination dates, using a split-split plot design with four replications over six years. Measurements included winter ground cover; stand composition; cover crop biomass, N concentration, and N uptake; and June soil NO3(--N. Rye planted in mid-September and terminated in late April averaged 5.1 Mg ha(-1 biomass, whereas mixtures averaged 4.1 Mg ha(-1 and hairy vetch 2.3 Mg ha(-1. Delaying planting by 2.5 weeks reduced average winter ground cover by 65%, biomass by 50%, and cover crop N accumulation by 40%. Similar reductions in biomass and N accumulation occurred for late March termination, compared with late April termination. Mixtures had less annual biomass variability than rye. Mixtures accumulated 103 kg ha(-1 N and had mean C:N ratio <17:1 when planted in mid-September and terminated in late April. June soil NO3(--N (0 to 30 cm depth averaged 62 kg ha(-1 for rye, 97 kg ha(-1 for the mixtures, and 119 kg ha(-1 for hairy vetch. Weeds comprised less of the mixtures biomass (20% weeds by weight at termination compared with the monocultures (29%. Cover crop mixtures provided a balance between biomass accumulation and N concentration, more consistent biomass over the six-year study, and were more effective at reducing winter weeds compared with monocultures.

Soybean growth and yield under cover crops

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Priscila de Oliveira

2013-04-01

Full Text Available The use of cover crops in no-tillage systems can provide better conditions for the development of soybean plants with positive effects on grain yield and growth analysis techniques allow researchers to characterize and understand the behavior of soybean plants under different straw covers. Thus, the aim of this study was to characterize, using growth analysis, yield components and agronomic performance of soybean under common bean, Brachiaria brizantha and pearl millet straws. The experiment was performed on a soil under cerrado in the municipality of Santo Antônio de Goiás, GO. The experiment was arranged in a randomized complete block design with three treatments (cover crops and five replications. Soybean grain yield was lower in the B. brizantha straw treatment (3,708 kg ha-1 than both in the pearl millet (4.772 kg ha-1 and common bean straw treatments (5,200 kg ha-1. The soybean growth analysis in B. brizantha, pearl millet and common bean allowed characterizing the variation in the production of dry matter of leaves, stems, pods and total and leaf area index that provided different grain yields. The cover crop directly affects the soybean grain yield.

Influence of Seeding Ratio, Planting Date, and Termination Date on Rye-Hairy Vetch Cover Crop Mixture Performance under Organic Management.

Science.gov (United States)

Lawson, Andrew; Cogger, Craig; Bary, Andy; Fortuna, Ann-Marie

2015-01-01

Cover crop benefits include nitrogen accumulation and retention, weed suppression, organic matter maintenance, and reduced erosion. Organic farmers need region-specific information on winter cover crop performance to effectively integrate cover crops into their crop rotations. Our research objective was to compare cover crop seeding mixtures, planting dates, and termination dates on performance of rye (Secale cereale L.) and hairy vetch (Vicia villosa Roth) monocultures and mixtures in the maritime Pacific Northwest USA. The study included four seed mixtures (100% hairy vetch, 25% rye-75% hairy vetch, 50% rye-50% hairy vetch, and 100% rye by seed weight), two planting dates, and two termination dates, using a split-split plot design with four replications over six years. Measurements included winter ground cover; stand composition; cover crop biomass, N concentration, and N uptake; and June soil NO3(-)-N. Rye planted in mid-September and terminated in late April averaged 5.1 Mg ha(-1) biomass, whereas mixtures averaged 4.1 Mg ha(-1) and hairy vetch 2.3 Mg ha(-1). Delaying planting by 2.5 weeks reduced average winter ground cover by 65%, biomass by 50%, and cover crop N accumulation by 40%. Similar reductions in biomass and N accumulation occurred for late March termination, compared with late April termination. Mixtures had less annual biomass variability than rye. Mixtures accumulated 103 kg ha(-1) N and had mean C:N ratio rye, 97 kg ha(-1) for the mixtures, and 119 kg ha(-1) for hairy vetch. Weeds comprised less of the mixtures biomass (20% weeds by weight at termination) compared with the monocultures (29%). Cover crop mixtures provided a balance between biomass accumulation and N concentration, more consistent biomass over the six-year study, and were more effective at reducing winter weeds compared with monocultures.

Epiphyte-cover on seagrass (Zostera marina L. leaves impedes plant performance and radial O2 loss from the below-ground tissue

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Kasper Elgetti Brodersen

2015-08-01

Full Text Available The O2 budget of seagrasses is a complex interaction between several sources and sinks, which is strongly regulated by light availability and mass transfer over the diffusive boundary layer (DBL surrounding the plant. Epiphyte growth on leaves may thus strongly affect the O2 availability of the seagrass plant and its capability to aerate its rhizosphere as a defence against plant toxins.We used electrochemical and fiber-optic microsensors to quantify the O2 flux, DBL and light microclimate around leaves with and without filamentous algal epiphytes. We also quantified the below-ground radial O2 loss from roots (~1 mm from the root-apex to elucidate how this below-ground oxic microzone was affected by the presence of epiphytes.Epiphyte-cover on seagrass leaves (~21% areal cover resulted in reduced light quality and quantity for photosynthesis, thus leading to reduced plant fitness. A ~4 times thicker diffusive boundary layer around leaves with epiphyte-cover impeded gas (and nutrient exchange with the surrounding water-column and thus the amount of O2 passively diffusing into the leaves in darkness. During light exposure of the leaves, radial oxygen loss from the below-ground tissue was ~2 times higher from plants without epiphyte-cover. In contrast, no O2 was detectable at the surface of the root-cap tissue of plants with epiphyte-cover during darkness, leaving the plants more susceptible to sulphide intrusion.Epiphyte growth on seagrass leaves thus negatively affects the light climate and O2 uptake in darkness, hampering the plants performance and thereby reducing the oxidation capability of its below-ground tissue.

The Growth of Agarwood Plants on the Different Canopy Covers Level and Fertilizer in Oil Palm Plantation

Science.gov (United States)

Rahayu Prastyaningsih, Sri; Azwin

2017-12-01

The development of agar wood plants in oil palm plantation requires the forestry techniques in order to obtain maximum production. In an oil palm stands, the age of plant will affect the height, diameter, population and stands density. The older age of an oil palm stands will affect the canopy cover on the forest floor. Agar wood plants are semi-tolerant growth and oil palm can be used as shade. Unilak has an oil palm plantation area of 10 hectares around the campus with 10 years old and 20 years old. The soil condition at the study is Podsolik Merah Kuning (PMK) which poor nutrient and needs fertilization to increase soil fertility. This study aims to find out the effect of age of oil palm stands and fertilization for optimal growth. The split plot design with 2 main plots of the age of palm tree ( 10 years old and 20 years old) and five kinds of fertilizing sub plot (without fertilizer, 40 gram/plant of NPK, 80 gram/plat of NPK, 120 gram/plant of NPK and 180 gram/plant of NPK were used. The results of this research showed that the age of palm tree (canopy cover) treatment gave non-significant influence on the growing of agar wood until it reaches 4 months of growth. The canopyy cover by 10 years old of oil palm tree produce the best response on height (15 cm) and diameter (0,4 cm) growth of agar woods..Fertilizing treatment di not give any significant influence on the heigh and diameter growth of agarwood plants until reach 3 months. The interaction by 10 years old of palm with fertilizing gave non significant results.

Plant assemblage composition and soil P concentration differentially affect communities of AM and total fungi in a semi-arid grassland.

Science.gov (United States)

Klabi, Rim; Bell, Terrence H; Hamel, Chantal; Iwaasa, Alan; Schellenberg, Mike; Raies, Aly; St-Arnaud, Marc

2015-01-01

Adding inorganic P- and N-fixing legumes to semi-arid grasslands can increase forage yield, but soil nutrient concentrations and plant cover may also interact to modify soil fungal populations, impacting short- and long-term forage production. We tested the effect of plant assemblage (seven native grasses, seven native grasses + the domesticated N-fixing legume Medicago sativa, seven native grasses + the native N-fixing legume Dalea purpurea or the introduced grass Bromus biebersteinii + M. sativa) and soil P concentration (addition of 0 or 200 P2O5 kg ha(-1) at sowing) on the diversity and community structure of arbuscular mycorrhizal (AM) fungi and total fungi over two consecutive years, using 454-pyrosequencing of 18S rDNA and ITS amplicons. Treatment effects were stronger in the wet year (2008) than the dry year (2009). The presence of an N-fixing legume with native grasses generally increased AM fungal diversity, while the interaction between soil P concentration and plant assemblage modified total fungal community structure in 2008. Excluding interannual variations, which are likely driven by moisture and plant productivity, AM fungal communities in semi-arid grasslands appear to be primarily affected by plant assemblage composition, while the composition of other fungi is more closely linked to soil P. © FEMS 2014. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Soybean growth and yield after single tillage and species mixture of cover plants

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Gislaine Piccolo de Lima

2012-10-01

Full Text Available The use of cover crops is important for the agricultural crop and soil management in order to improve the system and, consequently, to increase yield. Therefore, the present study analyzed the effect of crop residues of black oat (Avena strigosa Schreb. (BO and a cocktail (CO of BO, forage turnip (Raphanus sativus L. (FT and common vetch (Vicia sativa L. (V on the emergence speed index (ESI, seedling emergence speed (SES plant height and soybean yield in different intervals between cover crop desiccation with glyphosate 480 (3 L ha-1 and BRS 232 cultivar sowing. Plots of 5 x 2.5 m with 1 m of border received four treatments with BO cover crops and four with CO as well as a control for each cover crop, at random, with five replications. The plots were desiccated in intervals of 1, 10, 20 and 30 days before soybean seeding. The harvest was manual while yield was adjusted to 13% of moisture content. The experimental design was completely randomized with splitplots and means compared by the Scott and Knott test at 5% of significance. The results showed that CO of cover crops can be recommended for soybean to obtain a more vigorous seedling emergence, from 10 days after cover crop desiccation.

Calibration and Validation of Tundra Plant Functional Type Fractional Cover Mapping

Science.gov (United States)

Macander, M. J.; Nelson, P.; Frost, G. V., Jr.

2017-12-01

Fractional cover maps are being developed for selected tundra plant functional types (PFTs) across >500,000 sq. km of arctic Alaska and adjacent Canada at 30 m resolution. Training and validation data include a field-based training dataset based on point-intercept sampling method at hundreds of plots spanning bioclimatic and geomorphic gradients. We also compiled 50 blocks of 1-5 cm resolution RGB image mosaics in Alaska (White Mountains, North Slope, and Yukon-Kuskokwim Delta) and the Yukon Territory. The mosaics and associated surface and canopy height models were developed using a consumer drone and structure from motion processing. We summarized both the in situ measurements and drone imagery to determine cover of two PFTs: Low and Tall Deciduous Shrub, and Light Fruticose/Foliose Lichen. We applied these data to train 2 m (limited extent) and 30 m (wall to wall) maps of PFT fractional cover for shrubs and lichen. Predictors for 2 m models were commercial satellite imagery such as WorldView-2 and Worldview-3, analyzed on the ABoVE Science Cloud. Predictors for 30 m models were primarily reflectance composites and spectral metrics developed from Landsat imagery, using Google Earth Engine. We compared the performance of models developed from the in situ and drone-derived training data and identify best practices to improve the performance and efficiency of arctic PFT fractional cover mapping.

Comparison of dwarf bamboos (Indocalamus sp.) leaf parameters to determine relationship between spatial density of plants and total leaf area per plant.

Science.gov (United States)

Shi, Pei-Jian; Xu, Qiang; Sandhu, Hardev S; Gielis, Johan; Ding, Yu-Long; Li, Hua-Rong; Dong, Xiao-Bo

2015-10-01

The relationship between spatial density and size of plants is an important topic in plant ecology. The self-thinning rule suggests a -3/2 power between average biomass and density or a -1/2 power between stand yield and density. However, the self-thinning rule based on total leaf area per plant and density of plants has been neglected presumably because of the lack of a method that can accurately estimate the total leaf area per plant. We aimed to find the relationship between spatial density of plants and total leaf area per plant. We also attempted to provide a novel model for accurately describing the leaf shape of bamboos. We proposed a simplified Gielis equation with only two parameters to describe the leaf shape of bamboos one model parameter represented the overall ratio of leaf width to leaf length. Using this method, we compared some leaf parameters (leaf shape, number of leaves per plant, ratio of total leaf weight to aboveground weight per plant, and total leaf area per plant) of four bamboo species of genus Indocalamus Nakai (I. pedalis (Keng) P.C. Keng, I. pumilus Q.H. Dai and C.F. Keng, I. barbatus McClure, and I. victorialis P.C. Keng). We also explored the possible correlation between spatial density and total leaf area per plant using log-linear regression. We found that the simplified Gielis equation fit the leaf shape of four bamboo species very well. Although all these four species belonged to the same genus, there were still significant differences in leaf shape. Significant differences also existed in leaf area per plant, ratio of leaf weight to aboveground weight per plant, and leaf length. In addition, we found that the total leaf area per plant decreased with increased spatial density. Therefore, we directly demonstrated the self-thinning rule to improve light interception.

Integrity and life estimation of turbine runner cover in a hydro power plant

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A. Sedmak

2016-03-01

Full Text Available This paper presents integrity and life estimation of turbine runner cover in a vertical pipe turbines, Kaplan 200 MW nominal output power, produced in Russia, and built in six hydro-generation units of hydroelectric power plant „Đerdap 1” in Serbia. Fatigue and corrosion-fatigue interaction have been taken into account using experimentally obtained material properties, as well as analytical and numerical calculations of stress state, to estimate appropriate safety factors. Fatigue crack growth rate, da/dN, was also calculated, indicated that internal defects of circular or elliptical shape, found out by ultrasonic testing, do not affect reliable operation of runner cover.

Soil respiration and photosynthetic uptake of carbon dioxide by ground-cover plants in four ages of jack pine forest

Science.gov (United States)

Striegl, Robert G.; Wickland, K.P.

2001-01-01

Soil carbon dioxide (CO2) emission (soil respiration), net CO2 exchange after photosynthetic uptake by ground-cover plants, and soil CO2 concentration versus depth below land surface were measured at four ages of jack pine (Pinus banksiana Lamb.) forest in central Saskatchewan. Soil respiration was smallest at a clear-cut site, largest in an 8-year-old stand, and decreased with stand age in 20-year-old and mature (60-75 years old) stands during May-September 1994 (12.1, 34.6, 31.5, and 24.9 mol C??m-2, respectively). Simulations of soil respiration at each stand based on continuously recorded soil temperature were within one standard deviation of measured flux for 48 of 52 measurement periods, but were 10%-30% less than linear interpolations of measured flux for the season. This was probably due to decreased soil respiration at night modeled by the temperature-flux relationships, but not documented by daytime chamber measurements. CO2 uptake by ground-cover plants ranged from 0 at the clear-cut site to 29, 25, and 9% of total growing season soil respiration at the 8-year, 20-year, and mature stands. CO2 concentrations were as great as 7150 ppmv in the upper 1 m of unsaturated zone and were proportional to measured soil respiration.

Fluvial adjustments to soil erosion and plant cover changes in the Central Spanish Pyrenees

NARCIS (Netherlands)

Beguería, S.; López-Moreno, J.I.; Gómez-Villar, A.; Rubio, V.; Lana-Renault, N.; García-Ruiz, J.M.

2006-01-01

Until the middle of the 20th Century, Pyrenean rivers were characterized by braided channels, unstable sedimentary structures and an almost complete lack of plant cover in the alluvial plain, due to the high sediment yield in hillslopes and the occurrence of frequent and intense flooding. This

Evaluation of burial ground soil covers

International Nuclear Information System (INIS)

Fenimore, J.W.

1976-11-01

Solid radioactive waste burial at the Savannah River Plant between 1955 and 1972 filled a 76-acre site. Burial operations then were shifted to an adjacent site, and a program was begun to develop a land cover that would: (1) minimize soil erosion; and (2) protect the buried waste from deep-rooted plants, since radionuclides can be recycled by uptake through root systems. In anticipation of the need for a suitable soil cover, five grass species were planted on 20 plots (4 plots of each species) at the burial ground (Facility 643-G) in 1969. The grass plots were planted for evaluation of viability, root depth, and erosion protection existing under conditions of low fertility and minimum care. In addition, 16 different artificial soil covers were installed on 32 plots (each cover on two plots) to evaluate: (1) resistance of cover to deterioration from weathering; (2) resistance of cover to encroachment by deep-rooted plants; and (3) soil erosion protection provided by the cover. All test plots were observed and photographed in 1970 and in 1974. After both grass and artificial soil covers were tested five years, the following results were observed: Pensacola Bahia grass was the best of the five cover grasses tested; and fifteen of the sixteen artificial covers that were tested controlled vegetation growth and soil erosion. Photographs of the test plots will be retaken at five-year intervals for future documentation

Evaluating rapid ground sampling and scaling estimated plant cover using UAV imagery up to Landsat for mapping arctic vegetation

Science.gov (United States)

Nelson, P.; Paradis, D. P.

2017-12-01

The small stature and spectral diversity of arctic plant taxa presents challenges in mapping arctic vegetation. Mapping vegetation at the appropriate scale is needed to visualize effects of disturbance, directional vegetation change or mapping of specific plant groups for other applications (eg. habitat mapping). Fine spatial grain of remotely sensed data (ca. 10 cm pixels) is often necessary to resolve patches of many arctic plant groups, such as bryophytes and lichens. These groups are also spectrally different from mineral, litter and vascular plants. We sought to explore method to generate high-resolution spatial and spectral data to explore better mapping methods for arctic vegetation. We sampled ground vegetation at seven sites north or west of tree-line in Alaska, four north of Fairbanks and three northwest of Bethel, respectively. At each site, we estimated cover of plant functional types in 1m2 quadrats spaced approximately every 10 m along a 100 m long transect. Each quadrat was also scanned using a field spectroradiometer (PSR+ Spectral Evolution, 400-2500 nm range) and photographed from multiple perspectives. We then flew our small UAV with a RGB camera over the transect and at least 50 m on either side collecting on imagery of the plot, which were used to generate a image mosaic and digital surface model of the plot. We compare plant functional group cover ocular estimated in situ to post-hoc estimation, either automated or using a human observer, using the quadrat photos. We also compare interpolated lichen cover from UAV scenes to estimated lichen cover using a statistical models using Landsat data, with focus on lichens. Light and yellow lichens are discernable in the UAV imagery but certain lichens, especially dark colored lichens or those with spectral signatures similar to graminoid litter, present challenges. Future efforts will focus on integrating UAV-upscaled ground cover estimates to hyperspectral sensors (eg. AVIRIS ng) for better combined

Climate Impacts of Cover Crops

Science.gov (United States)

Lombardozzi, D.; Wieder, W. R.; Bonan, G. B.; Morris, C. K.; Grandy, S.

2016-12-01

Cover crops are planted in agricultural rotation with the intention of protecting soil rather than harvest. Cover crops have numerous environmental benefits that include preventing soil erosion, increasing soil fertility, and providing weed and pest control- among others. In addition to localized environmental benefits, cover crops can have important regional or global biogeochemical impacts by increasing soil organic carbon, changing emissions of greenhouse trace gases like nitrous oxide and methane, and reducing hydrologic nitrogen losses. Cover crops may additionally affect climate by changing biogeophysical processes, like albedo and latent heat flux, though these potential changes have not yet been evaluated. Here we use the coupled Community Atmosphere Model (CAM5) - Community Land Model (CLM4.5) to test how planting cover crops in the United States may change biogeophysical fluxes and climate. We present seasonal changes in albedo, heat fluxes, evaporative partitioning, radiation, and the resulting changes in temperature. Preliminary analyses show that during seasons when cover crops are planted, latent heat flux increases and albedo decreases, changing the evaporative fraction and surface temperatures. Understanding both the biogeophysical changes caused by planting cover crops in this study and the biogeochemical changes found in other studies will give a clearer picture of the overall impacts of cover crops on climate and atmospheric chemistry, informing how this land use strategy will impact climate in the future.

Ecological analysis of plant cover of the permanent grassland ecosystem located in the vicinity of Novi Kneževac, Serbia

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Knežević Aleksa

2012-01-01

Full Text Available A total of 205 taxa and stands of 12 plant communities were found to comprise the plant cover of the permanent grassland on the solonetz and solonchakic solonetz soils located in the vicinity of the town of Novi Kneževac (Vojvodina Province, Serbia. The registered taxa included 177 plant species, six subspecies, eight varieties, 13 forms and one lusus. The ecological analysis of the flora involved 191 taxa. That group consisted of 177 species, six subspecies, three varieties and five forms. The three varieties, Aster tripolium L. var. pannonicus ( Jacq. Beck, Chenopodium rubrum L. subsp. botryoides Sm. var. crassifolium (Hornem Kov. and Sonchus arvensis L. var. uliginosus (M.B. Grec. were used for analysis because their higher taxonomic categories were not recorded in the studied flora. The five forms, Aster sedifolius L. f. subsquamosus Soy, Bromus commutatus Schrad. f. violaceus Podp., Mentha aquatica L. f. erromera Top., Poa bulbosa L. f. vivipara Koel. and Scleranthus annus L. f. minimus Schur., were used for the same reason. The ecological analysis encompassed stands of all 12 recorded communities, i.e. ass. Scirpo-Phragmitetum W. Koch 1926, ass. Bolboschoenetum maritimi continentale Soy (1927 1957, ass. Acorelletum pannonici Soy (1939 1947, ass. Puccinelletum limosae (Rapcs. 1927 Soy 1930, ass. Pholiuro-Plantaginetum tenuiflorae (Rapcs. 1927 Wendel. 1943, ass. Hordeetum histricis (Soy 1933 Wendel. 1943, ass. Camphorosmetum annuae (Rapcs. 1916 Soy 1933 corr. Soy 1938, ass. Agrostio-Alopecuretum pratensis Soy (1933 1947, ass. Agrostio-Eleochariti-Alopecuretu geniculati (Magyar1928 Soy (1939 1947, ass. Artemisio-Festucetum pseudovinae (Magyar 1928 Soy 1945, ass. Achilleo-Festucetum pseudovinae (Magyar 1928 Soy 1945 and ass. Festuco-Andropogonetum ischaemi Vučk. 1985. The ecological analysis of the plant cover indicated that halophytes made 30.37% of the flora of the permanent grassland near the town of Novi Kneževac, and that the stands of

Soil Erosion and runoff response to plant-cover strips on semiarid slopes (SE Spain)

NARCIS (Netherlands)

Martinez-Raya, A.; Duran Zuazo, V.H.; Francia-Martinez, J.R.

2006-01-01

Over a four-year period (1997-2000), soil loss and surface-runoff patterns were monitored in hillside erosion plots with almond trees under different plant-cover strips (thyme, barley and lentils) on the south flank of the Sierra Nevada (Lanjaron) in south-eastern Spain. The erosion plots (580 m

Total phenolics and antioxidant activity of five medicinal plant

International Nuclear Information System (INIS)

Sousa, Cleyton Marcos de M.; Silva, Hilris Rocha e; Vieira-Junior, Gerardo Magela; Ayres, Mariane Cruz C.; Costa, Charllyton Luis S. da; Araajo, Delton Servulo; Cavalcante, Luis Carlos D.; Barros, Elcio Daniel S.; Araujo, Paulo Breitner de M.; Brandao, Marcela S.; Chaves, Mariana H.

2007-01-01

This paper describes total phenolics content and antioxidant activity in the ethanolic extract of leaves, bark and roots of five medicinal plants: Terminalia brasiliensis Camb., Terminalia fagifolia Mart. and Zucc., Copernicia cerifera (Miller) H.E. Moore, Cenostigma macrophyllum Tul. var. acuminata Teles Freire and Qualea grandiflora Mart. The total phenolics content of the plant extracts, determined by the Folin-Ciocalteu method, varied from 250.0 ±8,2 to 763,63 ±13.03 mg of gallic acid equivalent/g dry EtOH extract. The antioxidant activity of extracts was evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay system. Extract of bark from T. brasiliensis, the most active, with an EC 50 value of 27.59 ± 0.82 μg/mL, was comparable to rutin (EC 50 = 27.80 ± 1.38) and gallic acid (EC 50 = 24.27 ± 0.31), used as positive controls. The relationship between total phenolic content and antioxidant activity was positive and significant for T. brasiliensis, C. macrophyllum and C. cerifera. (author)

Effects of Planting Dates, Irrigation Management and Cover Crops on Growth and Yield of Saffron (Crocus sativus L.

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A Koocheki

2017-08-01

coming spring (May, 2010. Therefore, data were analyzed as split-plot in the first year and split-split-plot in the second year. Data analysis was done using SAS 9.1 and means were compared using Duncan multiple range test in 5% level of probability. Results and discussion Results showed that most growth and flowering indices of saffron were significantly affected by experimental factors. Quantitative indices of saffron were decreased considerably by delaying in planting date in both studied years. The highest flower yield was obtained in June planting date (28 and 98 kg.ha-1 in 2009 and 2010, respectively, while the lowest was shown in October planting date (18 and 34 kg.ha-1 in 2009 and 2010, respectively. Enhanced growth and yield of saffron in spring planting date is because of real dormancy stage of corms in this time. All studied indices were superior in no-irrigated treatments after planting in both studied years. The flower yield was 9 and 43 kg.ha-1 in 2009 and 2010 in irrigated treatments, respectively, while these values were 37 and 78 kg.ha-1in 2009 and 2010 in no-irrigation treatment, respectively. It has been reported that irrigation during the creation of the primary leaves in the corm buds is negative, while irrigation after this period and simultaneous with the beginning of primary reproductive organs creation is suitable for saffron flowering. The application of cover crops improved partially the quantitative indices of saffron, particularly in Bitter vetch treatment. In addition, the highest flowering rate and the lowest leaf appearance rate were observed in June planting date, no-irrigation and Bitter vetch cover crop treatment. The positive effects of short-growth cycle companion crops on saffron is related to improvement of soil physical, biological and chemical properties, soil temperature regulation, prevention from nutrient leaching, N-fixation by Fabaceae species and help to weeds control. Conclusion In total, saffron corm planting few days

Influence of Seeding Ratio, Planting Date, and Termination Date on Rye-Hairy Vetch Cover Crop Mixture Performance under Organic Management

OpenAIRE

Lawson, Andrew; Cogger, Craig; Bary, Andy; Fortuna, Ann-Marie

2015-01-01

Cover crop benefits include nitrogen accumulation and retention, weed suppression, organic matter maintenance, and reduced erosion. Organic farmers need region-specific information on winter cover crop performance to effectively integrate cover crops into their crop rotations. Our research objective was to compare cover crop seeding mixtures, planting dates, and termination dates on performance of rye (Secale cereale L.) and hairy vetch (Vicia villosa Roth) monocultures and mixtures in the ma...

Total generating costs: coal and nuclear plants

International Nuclear Information System (INIS)

1979-02-01

The study was confined to single and multi-unit coal- and nuclear-fueled electric-generating stations. The stations are composed of 1200-MWe PWRs; 1200-MWe BWRs; 800-and 1200-MWe High-Sulfur Coal units, and 800- and 1200-MWe Low-Sulfur Coal units. The total generating cost estimates were developed for commercial operation dates of 1985 and 1990; for 5 and 8% escalation rates, for 10 and 12% discount rates; and, for capacity factors of 50, 60, 70, and 80%. The report describes the methodology for obtaining annualized capital costs, levelized coal and nuclear fuel costs, levelized operation and maintenance costs, and the resulting total generating costs for each type of station. The costs are applicable to a hypothetical Middletwon site in the Northeastern United States. Plant descriptions with general design parameters are included. The report also reprints for convenience, summaries of capital cost by account type developed in the previous commercial electric-power cost studies. Appropriate references are given for additional detailed information. Sufficient detail is given to allow the reader to develop total generating costs for other cases or conditions

Effect of road side dust pollution on the growth and total chlorophyll ...

African Journals Online (AJOL)

The effect of dust in Vitis vinifera L. on its pigmentation and growth was studied in 2012. Measurements were taken for plants in the Campus University of Balochistan, Quetta. A significant reduction in plant length, cover, number of leaves and total chlorophyll contents for V. vinifera L. was observed. The maximum reduction ...

Effect of Cover Crops on Vertical Distribution of Leaf Area and Dry Matter of Soybean (Glycine max L. in Competition with Weeds

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seyyedeh samaneh hashemi

2017-08-01

foxtail (Setaria viridis L., foxtail grass (Alopecurus myosuroides Huds, and red root pigweed (Amaranthus retroflexus L. in the experimental field. The other weed was considered as the others. At the soybean canopy closure stage, a vertical card board frame marked in 20-cm increments was used in the field as a guide to cut standing plants including soybean, cover crops and weeds. In each vertical layer of canopy, leaves and stem samples were separated. The leaf area both crops and weeds were measured with a leaf area meter LICOR-3000A (LI-COR, Lincoln, NE, USA. Stem and leaf samples oven dried. Results and discussion The results showed that the maximum leaf area and dry matter of soybean was varied in different layers of canopy depending on the type of cover crop and cover crop planting time, while delaying in planting of cover crop causes lower leaf area and dry matter than the plants were planted at the same time with soybean. In most cases, the maximum leaf area index and dry matter accumulation of weeds were obtained in primary layer (0-20 cm. The maximum weed leaf area (290.4 cm2 was observed in simultaneous planting of soybean with fenugreek and maximum of total weed dry matter (12.4 g.plant-1 was observed in soybean without weeding, while the minimum of weed total leaf area and total weed dry matter (0 cm2 and 0 g.plant-1, respectively was achieved in planting of winter vetch after 21 days of soybean planting. Also delayed planting of winter vetch produced the maximum grain yield (3792.6 kg.ha-1 of soybean in weedy plots, where it had the greatest weed suppressive ability than other cover crops. Conclusion Winter vetch can suppress weed with competition and allelopathic mechanism, so we can conclude that winter vetch planting21 days after soybean planting is suitable replacement for weed suppression in sustainable agriculture.

A regional assessment of white-tailed deer effects on plant invasion

Science.gov (United States)

Mortensen, David A; Smithwick, Erica A H; Kalisz, Susan; McShea, William J; Bourg, Norman A; Parker, John D; Royo, Alejandro A; Abrams, Marc D; Apsley, David K; Blossey, Bernd; Boucher, Douglas H; Caraher, Kai L; DiTommaso, Antonio; Johnson, Sarah E; Masson, Robert; Nuzzo, Victoria A

2018-01-01

Abstract Herbivores can profoundly influence plant species assembly, including plant invasion, and resulting community composition. Population increases of native herbivores, e.g. white-tailed deer (Odocoileus virginianus), combined with burgeoning plant invasions raise concerns for native plant diversity and forest regeneration. While individual researchers typically test for the impact of deer on plant invasion at a few sites, the overarching influence of deer on plant invasion across regional scales is unclear. We tested the effects of deer on the abundance and diversity of introduced and native herbaceous and woody plants across 23 white-tailed deer research sites distributed across the east-central and north-eastern USA and representing a wide range of deer densities and invasive plant abundance and identity. Deer access/exclusion or deer population density did not affect introduced plant richness or community-level abundance. Native and total plant species richness, abundance (cover and stem density) and Shannon diversity were lower in deer-access vs. deer-exclusion plots. Among deer-access plots, native species richness, native and total cover, and Shannon diversity (cover) declined as deer density increased. Deer access increased the proportion of introduced species cover (but not of species richness or stem density). As deer density increased, the proportion of introduced species richness, cover and stem density all increased. Because absolute abundance of introduced plants was unaffected by deer, the increase in proportion of introduced plant abundance is likely an indirect effect of deer reducing native cover. Indicator species analysis revealed that deer access favoured three introduced plant species, including Alliaria petiolata and Microstegium vimineum, as well as four native plant species. In contrast, deer exclusion favoured three introduced plant species, including Lonicera japonica and Rosa multiflora, and 15 native plant species. Overall, native

A regional assessment of white-tailed deer effects on plant invasion

Energy Technology Data Exchange (ETDEWEB)

Averill, Kristine M. [Ecology Intercollege Graduate Degree Program, The Pennsylvania State University, University Park, PA, USA; Department of Plant Sciences, The Pennsylvania State University, University Park, PA, USA; Mortensen, David A. [Ecology Intercollege Graduate Degree Program, The Pennsylvania State University, University Park, PA, USA; Department of Plant Sciences, The Pennsylvania State University, University Park, PA, USA; Smithwick, Erica A. H. [Ecology Intercollege Graduate Degree Program, The Pennsylvania State University, University Park, PA, USA; Department of Geography, The Pennsylvania State University, University Park, PA, USA; Kalisz, Susan [Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN, USA; McShea, William J. [Smithsonian Conservation Biology Institute, Front Royal, VA, USA; Bourg, Norman A. [Smithsonian Conservation Biology Institute, Front Royal, VA, USA; Parker, John D. [Smithsonian Environmental Research Center, Edgewater, MD, USA; Royo, Alejandro A. [United States Department of Agriculture Forest Service, Northern Research Station, Irvine, PA, USA; Abrams, Marc D. [Ecology Intercollege Graduate Degree Program, The Pennsylvania State University, University Park, PA, USA; Department of Ecosystem Science and Management, The Pennsylvania State University, University Park, PA, USA; Apsley, David K. [Department of Extension, The Ohio State University, Jackson, OH, USA; Blossey, Bernd [Department of Natural Resources, Cornell University, Ithaca, NY, USA; Boucher, Douglas H. [Department of Biology, Hood College, Frederick, MD, USA; Caraher, Kai L. [Department of Biology, Hood College, Frederick, MD, USA; DiTommaso, Antonio [Soil and Crop Sciences Section, Cornell University, Ithaca, NY, USA; Johnson, Sarah E. [Ecology Intercollege Graduate Degree Program, The Pennsylvania State University, University Park, PA, USA; Department of Ecosystem Science and Management, The Pennsylvania State University, University Park, PA, USA; Masson, Robert [National Park Service, Morristown National Historical Park, Morristown, NJ, USA; Nuzzo, Victoria A. [Natural Area Consultants, Richford, NY, USA

2017-12-07

Herbivores can profoundly influence plant species assembly, including plant invasion, and resulting community composition. Population increases of native herbivores, e.g., white-tailed deer (Odocoileus virginianus), combined with burgeoning plant invasions raise concerns for native plant diversity and forest regeneration. While individual researchers typically test for the impact of deer on plant invasion at a few sites, the overarching influence of deer on plant invasion across regional scales is unclear. We tested the effects of deer on the abundance and diversity of introduced and native herbaceous and woody plants across 23 white-tailed deer research sites distributed across the east central and northeastern United States and representing a wide range of deer densities and invasive plant abundance and identity. Deer access/exclusion or deer population density did not affect introduced plant richness or community-level abundance. Native and total plant species richness, abundance (cover and stem density), and Shannon diversity were lower in deer-access vs. deer-exclusion plots. Among deer access plots, native species richness, native and total cover, and Shannon diversity (cover) declined as deer density increased. Deer access increased the proportion of introduced species cover (but not of species richness or stem density). As deer density increased, the proportion of introduced species richness, cover, and stem density all increased. Because absolute abundance of introduced plants was unaffected by deer, the increase in proportion of introduced plant abundance is likely an indirect effect of deer reducing native cover. Indicator species analysis revealed that deer access favored three introduced plant species, including Alliaria petiolata and Microstegium vimineum, as well as four native plant species. In contrast, deer exclusion favored three introduced plant species, including Lonicera japonica and Rosa multiflora, and fifteen native plant species. Overall

Degradation of Total Petroleum Hydrocarbon in Phytoremediation Using Terrestrial Plants

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Mushrifah Idris

2014-06-01

Full Text Available This study focused on the total petroleum hydrocarbon (TPH degradation in phytoremediation of spiked diesel in sand. The diesel was added to the sand that was planted with terrestrial plants. Four selected terrestrial plants used were Paspalum vaginatum Sw, Paspalums crobiculatum L. varbispicatum Hack, Eragrotis atrovirens (Desf. Trin. ex Steud and Cayratia trifolia (L. Domin since all the plants could survive at a hydrocarbon petroleum contaminated site in Malaysia. The samplings were carried out on Day 0, 7, 14, 28, 42 and 72. The analysis of the TPH was conducted by extracting the spiked sand using ultrasonic extraction. The determination of the TPH concentration in the sand was performed using GC-FID. The degradation of TPH depends on the plant species and time of exposure. The highest percentage degradation by P. vaginatum, P. scrobiculatum, E. atrovirens and C. trifolia were 91.9, 74.0, 68.9 and 62.9%, respectively. In conclusion, the ability to degrade TPH by plants were P. vaginatum > P. scrobiculatum > E. atrovirens> C. trifolia.

Power plant project success through total productive generation

Energy Technology Data Exchange (ETDEWEB)

Kaivola, R.; Tamminen, L.

1996-11-01

The Total Productive Generation concept (TPG) defines the lines of action adopted by IVO Generation Services Ltd (IGS) for the operation and maintenance of power plants. The TPG concept is based on procedures tested in practice. The main idea of TPG is continuous development of quality, which is a joint effort of the entire staff. Its objective is to benefit IGS`s own staff and, in particular, the company`s customers. (orig.)

Total pleural covering technique for intractable pneumothorax in patient with Ehlers-Danlos syndrome.

Science.gov (United States)

Kadota, Yoshihisa; Fukui, Eriko; Kitahara, Naoto; Okura, Eiji; Ohta, Mitsunori

2016-07-01

We report a patient with vascular-type Ehlers-Danlos syndrome (vEDS) who developed pneumothorax and was treated with a total pleural covering technique (TPC). A 24-year-old man developed repeat pneumothorax with intermittent hemo-sputum. Based on unusual radiological manifestations of lung lesions and physical findings, EDS was suspected as an underlying cause of the pneumothorax. Surgical treatment was performed using a mediastinal fat pad and TPC, and no relapse was seen up to 2 years after surgery. TPC is a less invasive surgical approach for selected patients with vEDS. Accurate underlying diagnosis of vEDS and systemic evaluation of vascular complications are necessary before planning surgery.

Mineralization of organic phosphorus in soil size fractions under different vegetation covers in the north of Rio de Janeiro

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Joice Cleide de Oliveira Rita

2013-10-01

Full Text Available In unfertilized, highly weathered tropical soils, phosphorus (P availability to plants is dependent on the mineralization of organic P (Po compounds. The objective of this study was to estimate the mineralization of total and labile Po in soil size fractions of > 2.0, 2.0-0.25 and 2.0 and 2.0-0.25 mm fractions, respectively. In contrast, there was an average increase of 90 % of total Po in microaggregates of 2.0 (-50 % and < 0.25 mm (-76 % fractions, but labile Po increased by 35 % in the 2.0-0.25 mm fraction. The Po fraction relative to total extracted P and total labile P within the soil size fractions varied with the vegetation cover and incubation time. Therefore, the distribution of P fractions (Pi and Po in the soil size fraction revealed the distinctive ability of the cover species to recycle soil P. Consequently, the potential of Po mineralization varied with the size fraction and vegetation cover. Because Po accounted for most of the total labile P, the P availability to plants was closely related to the mineralization of this P fraction.

Intensity of Ground Cover Crop Arachis pintoi, Rhizobium Inoculation and Phosphorus Application and Their Effects on Field Growth and Nutrient Status of Cocoa Plants

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John Bako Baon

2006-08-01

Full Text Available Arachis pintoiis potentially as a cover crop for cocoa (Theobroma cacaoL. farm, however information regarding its effect on the growth of cocoa plants in the field is very limited. The objective of this experiment is to investigate the combined influence of ground cover crop A. pintoi, rhizobial bacterial inoculation and phosphorus (P fertilizer on the growth of cocoa in the field and nutrient status. This experiment laid out in split-split plot design consisted of three levels of cover crop (without, A. pintoiand Calopogonium caeruleum, two levels of rhizobium inoculation (not inoculated and inoculated and two levels of phosphorus application (no P added and P added. The results showed that in field condition the presence of A. pintoias cover crop did not affect the growth of cocoa. On the other hand, C. caeruleumas cover crop tended to restrict cocoa growth compared to A. pintoi. Application of P increased leaf number of cocoa plant. Biomass production of A. pintoiwas 40% higher than C. caeruleum. Soil organic carbon and nitrogen contents were not affected by ground cover crops, though higher value (0.235% N and 1.63% organic C was obtained from combined treatments of inoculation and P addition or neither inoculation nor P addition. In the case of no rhizobium inoculation, soil N content in cocoa farm with A. pintoicover crop was lower than that of without cover crop or with C. caeruleum. Cover crop increased plant N content when there was no inoculation, on the other hand rhizobium inoculation decreased N content of cocoa tissue. Tissue P content of cocoa plant was not influenced by A. Pintoicover crop or by rhizobium inoculation, except that the P tissue content of cocoa was 28% higher when the cover crop was C. caeruleumand inoculated. Key words : Arachis pintoi, Theobroma cacao, Calopogonium caeruleum, rhizobium, nitrogen, phosphorus.

Cover technology demonstration for low-level radioactive sites

International Nuclear Information System (INIS)

Barnes, F.J.; Warren, J.L.

1988-01-01

The performance of a shallow land burial site in isolating low-level radioactive and mixed waste is strongly influenced by the behavior of the precipitation falling on the site. Predicting the long-term integrity of a cover design requires a knowledge of the water balance dynamics, and the use of predictive models. The multiplicity of factors operating on a site in the years post-closure (precipitation intensity and duration, soil conditions, vegetation seasonality and variability) have made it extremely difficult to predict the effects of natural precipitation with accuracy. Preliminary results are presented on a three-year field demonstration at Los Alamos National Laboratory to evaluate the influence of different waste trench cap designs on water balance under natural precipitation. Erosion plots having two different vegetative covers (shrubs and grasses) and with either gravel-mulched or unmulched soil surface treatments have been established on three different soil profiles on an inactive waste site. Total runoff and soil loss from each plot are measured biweekly while plant canopy cover is measured seasonally. Preliminary results from the first year show that the application of a gravel mulch reduced runoff by 73 to 90%. Total soil loss was reduced by 83 to 93% by the mulch treatment. On unmulched plots, grass cover reduced both runoff and soil loss by about 50% compared to the shrub plots. Soil moisture reduction during the growing season was more pronounced on the shrub plots. This indicates that a more complex vegetative cover provides greater soil moisture storage capacity for winter precipitation than the usual grass cover

Entisol land characteristics with and without cover crop (Mucuna bracteata) on rubber plantation

Science.gov (United States)

Sakiah; Sembiring, M.; Hasibuan, J.

2018-02-01

Optimal nutrient delivery is one way to improve the quality and quantity of crop production. This is because the crops needs for nutrient is quite high, while the soil capacity in providing nutrients is limited. In addition to fertilization, nutrients can be given in the form of added organic material or planted as cover crop. The research took place from April to August 2016 in Bandar Pinang, Bandar Sumatera Indonesia Ltd. (SIPEF Group) plantation, with survey method. Soil samples were taken based on: Topography (flat and slope 15-30%), cover crop (with or without Mucuna bracteata) and plant age (seedling periods 1, 2 and 3). The soil sample is taken composite by zig zag method. The observed parameters were organic matter, N total, soil texture, bulk density and infiltration rate. Mucuna bracteata planting increased the contain of soil organic matter by 30.43% in flat area and 53.33% in hilly area, amount of N total soil by 27.27% in flat area and 7.69% at hilly area, bulk density 3.73 % In flat area and 0.41% in hilly area, soil infiltration by 48.88% with sandy clay dominant soil texture.

The Influence of Garden Size and Floral Cover on Pollen Deposition in Urban Community Gardens

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Kevin C. Matteson

2009-01-01

Full Text Available Many cucurbits, such as cucumbers, squashes and pumpkins, depend on pollinating bees in order to set fruit. However, fruit yield and progeny vigor in these plants generally decreases as heterospecific pollen deposition increases. We studied how the spatial area dedicated to cucumbers (Cucumis sativis, versus other flowering plants, influenced the deposition of conspecific and heterospecific pollen on cucumber plants in New York City community gardens. We also examined the effect of garden size on conspecific and heterospecific pollen deposition on cucumber plants. Female flowers were collected from potted cucumber plants that had been experimentally placed into the gardens, specifically for this study, or that were established in raised beds by members of the community garden. In the laboratory, pollen grains were isolated from the flower by acetolysis, and the number of heterospecific and conspecific cucumber pollen grains were quantified. Conspecific pollen deposition was positively and significantly associated with the size of a community garden, as well as with the area of each garden dedicated to non-cucumber, flowering plants (i.e. floral cover and the area of each garden dedicated to cucumber plants (i.e. cucumber cover. Although floral cover explained a greater proportion of the variance, cucumber cover had the strongest effect on conspecific pollen deposition. Heterospecific pollen deposition was positively and significantly related to garden area. However, no significant relationship was found between heterospecific pollen deposition and floral cover, or cucumber cover. Based upon these results, we hypothesize that floral cover positively impacts conspecific pollen deposition by attracting a greater number of pollinators into an urban garden, and that total cucumber area positively impacts conspecific pollen deposition when pollinators are locally foraging within a garden. We suggest that the arrangement of plants within a garden can

A resistance representation of schemes for evaporation from bare and partly plant-covered surfaces for use in atmospheric models

Energy Technology Data Exchange (ETDEWEB)

Mihailovic, D.T.; Pielke, R.A.; Rajkovic, B.; Lee, T.J.; Jeftic, M. (Novi Sad Univ. (Yugoslavia) Colorado State Univ., Fort Collins (United States) Belgrade Univ. (Yugoslavia))

1993-06-01

In the parameterization of land surface processes, attention must be devoted to surface evaporation, one of the main processes in the air-land energy exchange. One of the most used approaches is the resistance representation which requires the calculation of aerodynamic resistances. These resistances are calculated using K theory for different morphologies of plant communities; then, the performance of the evaporation schemes within the alpha, beta, and their combination approaches that parameterize evaporation from bare and partly plant-covered soil surfaces are discussed. Additionally, a new alpha scheme is proposed based on an assumed power dependence alpha on volumetric soil moisture content and its saturated value. Finally, the performance of the considered and the proposed schemes is tested based on time integrations using real data. The first set was for 4 June 1982, and the second for 3 June 1981 at the experimental site in Rimski Sancevi, Yugoslavia, on chernozem soil, as representative for a bare, and partly plant-covered surface, respectively. 63 refs.

The Effect of Biofertilizers and Winter Cover Crops on Essential Oil Production and Some Agroecological Characteristics of Basil (Ocimum basilicum L.

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M Jahan

2013-04-01

Full Text Available In searching for new strategies of medicinal plant production with high yield but without undesirable compounds or effects, it is important to investigate unconventional alternatives such as application of PGPR and cover crops cultivation. This experiment was conducted in a split plots arrangement with two factors based on randomized complete block design with three replications during years 2009-10, at Research Farm of Ferdowsi University of Mashhad. Cultivation and no cultivation of cover crops in autumn assigned to the main plots. The sub factor was biofertilizer application with four levels, included 1-Nitroxin (containing Azotobacter spp. and Azospirillum spp., 2-Biophosphorous (Bacillus sp. and Pseudomonas sp., 3-Nitroxin + Biophosphorous and 4-Control. During growing season plants were harvested by three cuts. Results showed that total shoots dry weight, leaves yield and LAI in plants under no cover crop cultivation had a significant advantage. Biofertilizers increased most characteristics e.g. fresh and dry total shoot yield, dry leaves and LAI. The interaction between fertilizer and cover crop was significant, as the highest yield of fresh shoots was observed in mix of nitroxin and biophosphorous with no cover crop, the highest and the lowest of leaf and green area index were obtained in plants treated by nitroxin without cover crop and biophosphorous with cover crop, respectively. Plants harvested in cut 3 had the lowest LAI and other two cuts had no significant difference concerning this trait. The highest and the lowest fresh and dry shoot yield were observed in cut 2 and 1, respectively. The most essential oil yield was in cut 2 and 3 (without significant difference and cut 1 was the lowest. The results showed that the interaction between biofertilizers and no cover crop cultivation was significant, as use of the biofertilizers especially nitroxin and biophosphorous in no cover crop condition enhanced the most characteristics of

Soil-covered strategy for ecological restoration alters the bacterial community structure and predictive energy metabolic functions in mine tailings profiles.

Science.gov (United States)

Li, Yang; Sun, Qingye; Zhan, Jing; Yang, Yang; Wang, Dan

2017-03-01

Native soil amendment has been widely used to stabilize mine tailings and speed up the development of soil biogeochemical functions before revegetation; however, it remains poorly understood about the response of microbial communities to ecological restoration of mine tailings with soil-covered strategy. In this study, microbial communities along a 60-cm profile were investigated in mine tailings during ecological restoration of two revegetation strategies (directly revegetation and native soil covered) with different plant species. The mine tailings were covered by native soils as thick as 40 cm for more than 10 years, and the total nitrogen, total organic carbon, water content, and heavy metal (Fe, Cu, and Zn) contents in the 0-40 cm intervals of profiles were changed. In addition, increased microbial diversity and changed microbial community structure were also found in the 10-40 cm intervals of profiles in soil-covered area. Soil-covered strategy rather than plant species and soil depth was the main factor influencing the bacterial community, which explained the largest portion (29.96%) of the observed variation. Compared directly to revegetation, soil-covered strategy exhibited the higher relative abundance of Acidobacteria and Deltaproteobacteria and the lower relative abundance of Bacteroidetes, Gemmatimonadetes, Betaproteobacteria, and Gammaproteobacteria. PICRUSt analysis further demonstrated that soil-covered caused energy metabolic functional changes in carbon, nitrogen, and sulfur metabolism. Given all these, the soil-covered strategy may be used to fast-track the establishment of native microbial communities and is conducive to the rehabilitation of biogeochemical processes for establishing native plant species.

Total quality drives nuclear plant improvements

International Nuclear Information System (INIS)

Richey, R.B.

1991-01-01

Total quality (TQ) at Carolina Power and Light (CP and L) is fulfilling a 1985 vision of Sherwood H. Smith, Jr., CP and L's chairman, president, and chief executive officer. The TQ concept has provided a way for employees to align their creative energies toward meeting the business needs of the company. Throughout CP and L, TQ has been recognized as the vehicle for reducing operating costs and improving customer satisfaction. Within the nuclear organization, application of the TQ process has helped to improve communications, resolve challenges, and provide more consistent work practices among CP and L's three nuclear plants. Total quality was introduced from the top down, with initial benefits coming from team interactions. Senior management at CP and L defined the corporate expectations and outlined the training requirements for implementing TQ. Management staffs at each organizational level became steering committees for TQ team activities within their departments. Teams of employees most knowledgeable about a given work area were empowered to solve problems or overcome obstacles related to that work area. Employees learned to become better team players and to appreciate the quality of decisions reached through group consensus. Now, formalized methods that started TQ are becoming part of the day-to-day work ethic

Heavy metal leaching from mine tailings as affected by plants

Energy Technology Data Exchange (ETDEWEB)

Zhu, D.; Schwab, A.P.; Banks, M.K.

1999-12-01

A column experiment was conducted to determine the impact of soil cover and plants on heavy metal leaching from mine tailings and heavy metal contaminated soil. Columns made of PVC were constructed with 30 cm subsoil covered by 30 cm of mine tailings followed by 0, 30, or 60 cm subsoil covered by 30 cm of mine tailings followed by 0, 30, or 60 cm of clean topsoil. Two grasses, tall fescue (Festuca arundinacea Schreb.) and big bluestem (Andropogon gerardii), were grown in the columns. The columns were leached at a slow rate for 1 yr with a 0.001 M CaCl{sub 2} solution under unsaturated conditions. The presence of both tall fescue and big bluestem increased Zn and Cd concentrations in the leachate. Lead concentrations in leachates were not affected by the presence of plants. Although plants generally reduced the total amount of water leached, total mass of Zn and Cd leached generally was not impacted by plants. Total mass of Pb leached was positively correlated with total leachate collected from each column. Covering the mine tailings with 60 cm of topsoil increased the mass of Zn and Cd leached relative to no topsoil. When the subsoil was absent, Zn and Cd leaching increased by as much as 20-fold, verifying the ability of soil to act as a sink for metals. Mine tailing remediation by establishing vegetation can reduce Pb movement but may enhance short-term Cd and Zn leaching. However, the changes were relatively small and do not outweigh the benefits of using vegetation in mine tailings reclamation.

A Total Pleural Covering for Lymphangioleiomyomatosis Prevents Pneumothorax Recurrence

Science.gov (United States)

Kurihara, Masatoshi; Mizobuchi, Teruaki; Kataoka, Hideyuki; Sato, Teruhiko; Kumasaka, Toshio; Ebana, Hiroki; Yamanaka, Sumitaka; Endo, Reina; Miyahashira, Sumika; Shinya, Noriko; Seyama, Kuniaki

2016-01-01

Background Spontaneous pneumothorax is a major and frequently recurrent complication of lymphangioleiomyomatosis (LAM). Despite the customary use of pleurodesis to manage pnenumothorax, the recurrence rate remains high, and accompanying pleural adhesions cause serious bleeding during subsequent lung transplantation. Therefore, we have developed a technique of total pleural covering (TPC) for LAM to wrap the entire visceral pleura with sheets of oxidized regenerated cellulose (ORC) mesh, thereby reinforcing the affected visceral pleura and preventing recurrence. Methods Since January 2003, TPC has been applied during video-assisted thoracoscopic surgery for the treatment of LAM. The medical records of LAM patients who had TPC since that time and until August 2014 are reviewed. Results TPC was performed in 43 LAM patients (54 hemithoraces), 11 of whom required TPC bilaterally. Pneumothorax recurred in 14 hemithoraces (25.9%) from 11 patients (25.6%) after TPC. Kaplan-Meier estimates of recurrence-free hemithorax were 80.8% at 2.5 years, 71.7% at 5 years, 71.7% at 7.5 years, and 61.4% at 9 years. The recurrence-free probability was significantly better when 10 or more sheets of ORC mesh were utilized for TPC (P = 0.0018). TPC significantly reduced the frequency of pneumothorax: 0.544 ± 0.606 episode/month (mean ± SD) before TPC vs. 0.008 ± 0.019 after TPC (Ppneumothorax in LAM, was minimally invasive and rarely caused restrictive ventilatory impairment. PMID:27658250

AgRISTARS: Early warning and crop condition assessment. Plant cover, soil temperature, freeze, water stress, and evapotranspiration conditions

Science.gov (United States)

Wiegand, C. L. (Principal Investigator); Nixon, P. R.; Gausman, H. W.; Namken, L. N.; Leamer, R. W.; Richardson, A. J.

1981-01-01

Emissive (10.5 to 12.5 microns) and reflective (0.55 to 1.1 microns) data for ten day scenes and infrared data for six night scenes of southern Texas were analyzed for plant cover, soil temperature, freeze, water stress, and evapotranspiration. Heat capacity mapping mission radiometric temperatures were: within 2 C of dewpoint temperatures, significantly correlated with variables important in evapotranspiration, and related to freeze severity and planting depth soil temperatures.

Regularities of restoration of plant cover on the dumps of the Kuznetsk Basin

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A. N. Kupriyanov

2016-04-01

Full Text Available The article considers the issues of the restoration vegetation on the dumps of the coal enterprises of the Kuznetsk Basin. Studies have shown that the dumps have a wide range of environmental conditions and are potentially suitable for establishment of plants. To negative environmental factors at the mine dumps include the lack of productive moisture, failed penetration, contrasting temperature regime on the different elements of the relief, and low potential fertility of the embryonic soils. Positive – high humidity in the depressions, the high content of fine-grained deposits in the lower part of the elephant dumps, excessive accumulation of snow in the winter on separate dumping sites. On disturbed lands identified eight technogenic ecotopes, characterized by various microrelief, moisture level, amount of fine fractions of technogenic eluvium determining favorable, moderately favorable and unfavorable conditions for vegetation of disturbed land. Selected three stages of syngenesis: pioneer stage, simple plant communities and complex plant communities. The stage of zonal phytocenosis on the dumps was not detected. The basis of diagnostic signs consists of the projective cover, the nature of the host plants, the number of species part of the zonal species. The selected criteria are universal and can be applicable to most dumps. Speed of syngenetic succession does not depend on calendar age of the dumps, and environmental conditions, which are formed on separate sites.

Limited Impact of a Fall-Seeded, Spring-Terminated Rye Cover Crop on Beneficial Arthropods.

Science.gov (United States)

Dunbar, Mike W; Gassmann, Aaron J; O'Neal, Matthew E

2017-04-01

Cover crops are beneficial to agroecosystems because they decrease soil erosion and nutrient loss while increasing within-field plant diversity. Greater plant diversity within cropping systems can positively affect beneficial arthropod communities. We hypothesized that increasing plant diversity within annually rotated corn and soybean with the addition of a rye cover crop would positively affect the beneficial ground and canopy-dwelling communities compared with rotated corn and soybean grown without a cover crop. From 2011 through 2013, arthropod communities were measured at two locations in Iowa four times throughout each growing season. Pitfall traps were used to sample ground-dwelling arthropods within the corn and soybean plots and sweep nets were used to measure the beneficial arthropods in soybean canopies. Beneficial arthropods captured were identified to either class, order, or family. In both corn and soybean, community composition and total community activity density and abundance did not differ between plots that included the rye cover crop and plots without the rye cover crop. Most taxa did not significantly respond to the presence of the rye cover crop when analyzed individually, with the exceptions of Carabidae and Gryllidae sampled from soybean pitfall traps. Activity density of Carabidae was significantly greater in soybean plots that included a rye cover crop, while activity density of Gryllidae was significantly reduced in plots with the rye cover crop. Although a rye cover crop may be agronomically beneficial, there may be only limited effects on beneficial arthropods when added within an annual rotation of corn and soybean. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Transplanting native dominant plants to facilitate community development in restored coastal plain wetlands.

Energy Technology Data Exchange (ETDEWEB)

De Steven, Diane; Sharitz, Rebecca R.

2007-12-01

Abstract: Drained depressional wetlands are typically restored by plugging ditches or breaking drainage tiles to allow recovery of natural ponding regimes, while relying on passive recolonization from seed banks and dispersal to establish emergent vegetation. However, in restored depressions of the southeastern United States Coastal Plain, certain characteristic rhizomatous graminoid species may not recolonize because they are dispersal-limited and uncommon or absent in the seed banks of disturbed sites. We tested whether selectively planting such wetland dominants could facilitate restoration by accelerating vegetative cover development and suppressing non-wetland species. In an operational-scale project in a South Carolina forested landscape, drained depressional wetlands were restored in early 2001 by completely removing woody vegetation and plugging surface ditches. After forest removal, tillers of two rhizomatous wetland grasses (Panicum hemitomon, Leersia hexandra) were transplanted into singlespecies blocks in 12 restored depressions that otherwise were revegetating passively. Presence and cover of all plant species appearing in planted plots and unplanted control plots were recorded annually. We analyzed vegetation composition after two and four years, during a severe drought (2002) and after hydrologic recovery (2004). Most grass plantings established successfully, attaining 15%–85% cover in two years. Planted plots had fewer total species and fewer wetland species compared to control plots, but differences were small. Planted plots achieved greater total vegetative cover during the drought and greater combined cover of wetland species in both years. By 2004, planted grasses appeared to reduce cover of non-wetland species in some cases, but wetter hydrologic conditions contributed more strongly to suppression of non-wetland species. Because these two grasses typically form a dominant cover matrix in herbaceous depressions, our results indicated that

The Antioxidant Capacities and Total Phenolic Contents of Some Medicinal Plants in Iran

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Ali Mirzaei

2011-12-01

Full Text Available Background & Objectives: Free radicals are highly reactive molecules may cause great damage to cell membranes and DNA and Result in inducing oxidation DNA mutations leading to cancer, degenerative, and other diseases. Plant antioxidant derived may be preventive of free radical damages. Methods & Materials: The Stems and flower sample of plants air-dried, finely ground and were extracted by ethanol: water (70:30 for 48 h. Extracts were filtered and dried under vacuum. The antioxidant activity of five ethanolic extract of medicinal plants (Descurainia Sophia, Plantago major, Trachyspermum copticum L, Coriandrum sativum and Trigonella foenum-graecum from Iran were analysed by five different methods [1,1-diphenyl-2-picrylhydrazyl (DPPH radical, 2,2,azinobis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS radical cation, Ferric-reducing antioxidant power assay (FRAP, phosphomolybdenum (PMB and reducing power (RP]. In addition, for determination of antioxidant components total phenolic content was also analyzed. Results: The total phenolic content of medicinal plant ranges from 74 to 154.3 mg Gallic acid/g extract as measured by the Folin–Ciocalteau method. Values of DPPH varied from 15.5 to 19.6 µmol trolex/g. FRAP ranged from 124.2 to 753 µmol of Fe(II/g extract. Antioxidant activity of the Plantago major was always higher compared to the other plants extracts values of total phenols content and antioxidant capacity by DPPH, ABTS, FRAP, (154.33 mg GAE/g, 1856 µmol trolox, 750 µmol trolox and 1169 µmol of Fe(II/g, extract respectively. The range of total antioxidant activity by phosphomolybdenum method was 513.3 to 870 µmol trolox/g. The reducing ability of the tested extracts was between 0.31-1.26. Plantago majorwas also highest activity in both tests. Conclusion: This study clearly demonstrated that Plantago major crude extract exhibit significant antioxidant activity.

Efeito de hormônios vegetais sôbre o enraizamento de estacas de amoreira, plantadas em estufins, em posição normal e invertida Cuttings of Morus alba treated with plant hormones and planted in propagator covers with plastic covers, in reverse and normal systems

Directory of Open Access Journals (Sweden)

Antônio Castilho Rúbia

1965-01-01

Full Text Available No presente trabalho são relatados os resultados obtidos com o emprêgo de hormônios vegetais em estacas de amoreira, variedade Catânia 1, plantadas em estufins com cobertura de matéria plástica, em dois sistemas de plantio, invertido e normal. O sistema invertido apresentou melhor resultado no enraizamento das estacas. Com relação aos hormônios vegetais empregados, o ácido-beta-indolacético, na concentração de 100 mg/1 de água destilada, concorreu para aumentar a porcentagem de estacas enraizadas.In the present paper the results are reported that were obtained by the utilization of plant hormones on cuttings of Morus alba of the variety Catania 1, which were planted in propagator covers with plastic covers, obeying two planting systems, the reverse and the normal one. The reverse planting system showed better results in the rooting of the cuttings. As to the plant hormones used, the beta indolacetic acid, at a concentration of 100 mg to the litre of distilled water, contributed to increase the percentage of fixing the roots of the cuttings.

A Total Pleural Covering for Lymphangioleiomyomatosis Prevents Pneumothorax Recurrence.

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Masatoshi Kurihara

Full Text Available Spontaneous pneumothorax is a major and frequently recurrent complication of lymphangioleiomyomatosis (LAM. Despite the customary use of pleurodesis to manage pnenumothorax, the recurrence rate remains high, and accompanying pleural adhesions cause serious bleeding during subsequent lung transplantation. Therefore, we have developed a technique of total pleural covering (TPC for LAM to wrap the entire visceral pleura with sheets of oxidized regenerated cellulose (ORC mesh, thereby reinforcing the affected visceral pleura and preventing recurrence.Since January 2003, TPC has been applied during video-assisted thoracoscopic surgery for the treatment of LAM. The medical records of LAM patients who had TPC since that time and until August 2014 are reviewed.TPC was performed in 43 LAM patients (54 hemithoraces, 11 of whom required TPC bilaterally. Pneumothorax recurred in 14 hemithoraces (25.9% from 11 patients (25.6% after TPC. Kaplan-Meier estimates of recurrence-free hemithorax were 80.8% at 2.5 years, 71.7% at 5 years, 71.7% at 7.5 years, and 61.4% at 9 years. The recurrence-free probability was significantly better when 10 or more sheets of ORC mesh were utilized for TPC (P = 0.0018. TPC significantly reduced the frequency of pneumothorax: 0.544 ± 0.606 episode/month (mean ± SD before TPC vs. 0.008 ± 0.019 after TPC (P<0.0001. Grade IIIa postoperative complications were found in 13 TPC surgeries (24.1%.TPC successfully prevented the recurrence of pneumothorax in LAM, was minimally invasive and rarely caused restrictive ventilatory impairment.

Exclusion of brown lemmings reduces vascular plant cover and biomass in Arctic coastal tundra: resampling of a 50 + year herbivore exclosure experiment near Barrow, Alaska

International Nuclear Information System (INIS)

Johnson, D R; Lara, M J; Tweedie, C E; Shaver, G R; Batzli, G O; Shaw, J D

2011-01-01

To determine the role lemmings play in structuring plant communities and their contribution to the 'greening of the Arctic', we measured plant cover and biomass in 50 + year old lemming exclosures and control plots in the coastal tundra near Barrow, Alaska. The response of plant functional types to herbivore exclusion varied among land cover types. In general, the abundance of lichens and bryophytes increased with the exclusion of lemmings, whereas graminoids decreased, although the magnitude of these responses varied among land cover types. These results suggest that sustained lemming activity promotes a higher biomass of vascular plant functional types than would be expected without their presence and highlights the importance of considering herbivory when interpreting patterns of greening in the Arctic. In light of the rapid environmental change ongoing in the Arctic and the potential regional to global implications of this change, further exploration regarding the long-term influence of arvicoline rodents on ecosystem function (e.g. carbon and energy balance) should be considered a research priority.

Towards spatial assessment of carbon sequestration in peatlands: spectroscopy based estimation of fractional cover of three plant functional types

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G. Schaepman-Strub

2009-02-01

Full Text Available Peatlands accumulated large carbon (C stocks as peat in historical times. Currently however, many peatlands are on the verge of becoming sources with their C sequestration function becoming sensitive to environmental changes such as increases in temperature, decreasing water table and enhanced nitrogen deposition. Long term changes in vegetation composition are both, a consequence and indicator of future changes in C sequestration. Spatial continuous accurate assessment of the vegetation composition is a current challenge in keeping a close watch on peatland vegetation changes. In this study we quantified the fractional cover of three major plant functional types (PFTs; Sphagnum mosses, graminoids, and ericoid shrubs in peatlands, using field spectroscopy reflectance measurements (400–2400 nm on 25 plots differing in PFT cover. The data was validated using point intercept methodology on the same plots. Our results showed that the detection of open Sphagnum versus Sphagnumcovered by vascular plants (shrubs and graminoids is feasible with an R² of 0.81. On the other hand, the partitioning of the vascular plant fraction into shrubs and graminoids revealed lower correlations of R² of 0.54 and 0.57, respectively. This study was based on a dataset where the reflectance of all main PFTs and their pure components within the peatland was measured at local spatial scales. Spectrally measured species or plant community abundances can further be used to bridge scaling gaps up to canopy scale, ultimately allowing upscaling of the C balance of peatlands to the ecosystem level.

Effects of fire and three fire-fighting chemicals on main soil properties, plant nutrient content and vegetation growth and cover after 10 years.

Science.gov (United States)

Fernández-Fernández, M; Gómez-Rey, M X; González-Prieto, S J

2015-05-15

The study addresses a knowledge-gap in the long-term ecological consequences of fire and fire-fighting chemicals. Ten years after a prescribed fire and the application of three fire-fighting chemicals, their effects on the soil-plant system were evaluated. Five treatments were established: unburnt soils (US) and burnt soils treated with water alone (BS), foaming agent (BS+Fo), Firesorb (BS+Fi) and ammonium polyphosphate (BS+Ap). Soils (0-2 cm depth) and foliar material of shrubs (Erica umbellata, Pterospartum tridentatum and Ulex micranthus) and trees (Pinus pinaster) were analysed for total N, δ(15)N, and soil-available and plant total macronutrients and trace elements. Soil pH, NH₄(+)-N and NO₃(-)-N; pine basal diameter and height; and shrub cover and height were also measured. Compared with US plots, burnt soils had less nitrates and more Mo. Although differences were not always significant, BS+Ap had the highest levels of soil available P, Na and Al. Plants from BS+Ap plots had higher values of δ(15)N (P. pinaster and E. umbellata), P (all species), Na (P. tridentatum and U. micranthus) and Mg (E. umbellata and P. tridentatum) than other treatments; while K in plants from BS+Ap plots was the highest among treatments for P. pinaster and the lowest for the shrubs. Pines in US plots were higher and wider than in burnt treatments, except for BS+Ap, where the tallest and widest trees were found, although half of them were either dead (the second highest mortality after BS+Fi) or had a distorted trunk. BS+Ap was the treatment with strongest effects on plants, showing E. umbellata the lowest coverage and height, P. tridentatum the highest coverage, U. micranthus one of the lowest coverages and being the only treatment where Genista triacanthos was absent. Consequently, it is concluded that both fire and ammonium polyphosphate application had significant effects on the soil-plant system after 10 years. Copyright © 2015 Elsevier B.V. All rights reserved.

Nuclear Liability and Insurance Cover for Risk of Nuclear Power Plants - Situation for Nuclear Installations in Germany

International Nuclear Information System (INIS)

Boediker, T.

1998-01-01

A dispute about nuclear liability and insurance cover for risks of nuclear power plants from an insurer's point of view has to determine and to judge the essential risk relevant factors. These are beside plant and site specific factors considerations of insurance restrictions in the extent of cover compared with the legal scope of liability for (re-)insurability's sake. Among such consideration are: financial limitation and obligation for its reinstatement, exclusions for gradual emissions of approved activities, armed conflicts, hostilities, civil war, insurrections or grave natural disaster and restrictions in the limitation and preclusion periods. In comparison with conventional liability risks there are some specialties to be considered some of which prove to be a risk relief other as a risk burden for insurance: Salvage expenses or interests and court costs to be paid by unsuccessful party in a lost litigation do not fall under legal liability and hence are excluded from the financial security cover so that are compensation is subject to agreed separate limits. A serious burden for the insurers can result out of the loss regulation costs in case of a severe nuclear accident. These expenses, which can exceed hundred million DM by far, are to be carried by the insurers in the frame of their obligation to investigate raised claims. Therefore the insurers should aim a fixed limitation in order to restrict their limit. (author)

Diversity of bacteria nesting the plant cover of north Sinai deserts, Egypt

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Amira L. Hanna

2013-01-01

Full Text Available North Sinai deserts were surveyed for the predominant plant cover and for the culturable bacteria nesting their roots and shoots. Among 43 plant species reported, 13 are perennial (e.g. Fagonia spp., Pancratium spp. and 30 annuals (e.g. Bromus spp., Erodium spp.. Eleven species possessed rhizo-sheath, e.g. Cyperus capitatus, Panicum turgidum and Trisetaria koelerioides. Microbiological analyses demonstrated: the great diversity and richness of associated culturable bacteria, in particular nitrogen-fixing bacteria (diazotrophs; the majority of bacterial residents were of true and/or putative diazotrophic nature; the bacterial populations followed an increasing density gradient towards the root surfaces; sizeable populations were able to reside inside the root (endorhizosphere and shoot (endophyllosphere tissues. Three hundred bacterial isolates were secured from studied spheres. The majority of nitrogen-fixing bacilli isolates belonged to Bacillus megaterium, Bacillus pumilus, Bacillus polymexa, Bacillus macerans, Bacillus circulans and Bacillus licheniformis. The family Enterobacteriaceae represented by Enterobacter agglomerans, Enterobacter sackazakii, Enterobacter cloacae, Serratia adorifera, Serratia liquefaciens and Klebsiella oxytoca. The non-Enterobacteriaceae population was rich in Pantoae spp., Agrobacterium rdiobacter, Pseudomonas vesicularis, Pseudomonas putida, Stenotrophomonas maltophilia, Ochrobactrum anthropi, Sphingomonas paucimobilis and Chrysemonas luteola. Gluconacetobacter diazotrophicus were reported inside root and shoot tissues of a number of tested plants. The dense bacterial populations reported speak well to the very possible significant role played by the endophytic bacterial populations in the survival, in respect of nutrition and health, of existing plants. Such groups of diazotrophs are good candidates, as bio-preparates, to support the growth of future field crops grown in deserts of north Sinai and irrigated by the

Block survey of wall covered with plant in the city of Tokyo [Japan] and evaluation of thermal environment of wall greening system

International Nuclear Information System (INIS)

Shibuya, K.; Soh, Y.; Satoh, S.

2007-01-01

There were 384 (8877 square m) walls which covered with plant on 10 square km in the city of Tokyo, and the green wall rate in the city of Tokyo was 0.88%. Vines, for example Parthenocissus tricuspidata and Hedera helix, were widely used. The factor of thinking better of the landscape in urban area was one of the easily management of plants. The three wall greening systems, a wall covered with hanging climbers and two types of self-contained living wall, mitigated the thermal environment. However its degree can be depended on the greening method and the greenery occupancy rate of wall

Plant-cover influence on the spatial distribution of radiocaesium deposits in forest ecosystems

International Nuclear Information System (INIS)

Guillitte, Olivier; Andolina, Jean; Koziol, Michel; Debauche, Antoine

1990-01-01

Since the Chernobyl nuclear accident, a major campaign of radioactive deposit measurements has been carried out on forest soils in Belgium and the Grand Duchy of Luxemburg. Three types of forest ecosystems have systematically been taken into account in each region: coniferous forests (mainly spruce stands), deciduous forests (mainly beech stands) and in clearings. Sampling and field measurements have been carried out in different places with regard to the plant cover: near the trunks, under the foliage, in a small gap, on soil with or without herbaceous or moss stratum. The samples have been collected and measured according to the different recognizable soil layers in order to evaluate the vertical deposit distribution. From overall measurements, one may observe a high spatial soil deposit variation which is mainly explained by the nature, structure and age of the forest stands and by the thickness and the nature of holorganic horizons. A particular interest of this study is the identification of the influence of stem flow and impluvium on forest-cover gaps and edges. (author)

Total quality management to improve gas plant profits

International Nuclear Information System (INIS)

Kovacs, K.; Wood, G.; Thompson, L.

1992-01-01

This paper describes the application of total quality management (TQM) techniques to the gas processing industry. It also assesses the profit potential for applying TQM in a typical plant situation. Companies utilizing TQM techniques will enjoy a competitive advantage. It represents a new way of doing business for the gas processing industry and incorporates many of Dr. W. Edwards Deming's methods which are often cited as one of the competitive advantages used by the Japanese. TQM can be described as a collection of systems or techniques that work toward two major objectives: To continuously improve the process or operation; and To view meeting the customer's needs as an important criterion for success. As applied to a typical U.S. gas processing operation, it involves several different techniques which are outlined in the paper. The benefits of TQM are detailed in this paper. All of these benefits go directly to a plant's bottom line profitability. The paper also describes ho to establish a program and identifies the factors necessary for successful implementation

Integration into plant biology and soil science has provided insights into the total environment.

Science.gov (United States)

Shao, Hongbo; Lu, Haiying; Xu, Gang; Marian, Brestic

2017-02-01

The total environment includes 5 closely-linking circles, in which biosphere and lithosphere are the active core. As global population increases and urbanization process accelerates, arable land is gradually decreasing under global climate change and the pressure of various types of environmental pollution. This case is especially for China. Land is the most important resources for human beings' survival. How to increase and manage arable land is the key for sustainable agriculture development. China has extensive marshy land that can be reclamated for the better potential land resources under the pre- condition of protecting the environment, which will be a good way for enlarging globally and managing arable land. Related studies have been conducted in China for the past 30years and now many results with obvious practical efficiency have been obtained. For summarizing these results, salt-soil will be the main target and related contents such as nutrient transport, use types, biodiversity and interactions with plants from molecular biology to ecology will be covered, in which the interactions among biosphere, lithosphere, atmosphere and anthroposphere will be focused on. Copyright © 2016 Elsevier B.V. All rights reserved.

Impact of the construction of a hydroelectric power plant on the land cover and use: study of the basin Lajeado Bonito - RS; Impacto da construcao de uma usina hidreletrica no uso e cobertura da terra: estudo da bacia Lajeado Bonito-RS

Energy Technology Data Exchange (ETDEWEB)

Tramontina, Juliana; Breunig, Fabio Marcelo [Universidade Federal de Santa Maria (UFSM), RS (Brazil)

2015-07-01

This work aims to analyze the impact of the construction of a hydroelectric power plant on land cover and use in Lajeado Bonito-RS watershed. The study evaluated the temporal evolution of land cover and use in the watershed for the period before and after to installation of hydroelectric plant Foz do Chapeco (2009 to 2010). For temporal analysis, two images were interpreted, one orbital image of High Resolution Camera (HRC) onboard of the CBERS-2B, acquired in December 29, 2009. And a high-resolution image obtained from Google Earth application, acquired at December 26, 2010. The land cover and use maps were generated by vector editing SPRING software. We found that the predominant land use related to agriculture and livestock, including bare soil. In 2009 this class accounted for 70.23% of the total area, while it come to represent 61.8% in 2010. At the same time, there was increase of areas with native forest cover, from 27.49% covered by forest in 2009, to 31% in 2010. The results showed that in both 2009 and 2010 years, approximately 49% of permanent preservation area were used inappropriately. (author)

Summer cover crops and soil amendments to improve growth and nutrient uptake of okra

Energy Technology Data Exchange (ETDEWEB)

Wang, Q.R.; Li, Y.C.; Klassen, W. [University of Florida, Homestead, FL (United States). Center for Tropical Research & Education

2006-04-15

A pot experiment with summer cover crops and soil amendments was conducted in two consecutive years to elucidate the effects of these cover crops and soil amendments on 'Clemson Spineless 80' okra (Abelmoschus esculentus) yields and biomass production, and the uptake and distribution of soil nutrients and trace elements. The cover crops were sunn hemp (Crotalaria juncea), cowpea (Vigna unguiculata), velvetbean (Mucuna deeringiana), and sorghum sudan-grass (Sorghum bicolor x S. bicolor var. sudanense) with fallow as the control. The organic soil amendments were biosolids (sediment from wastewater plants), N-Viro Soil (a mixture of biosolids and coal ash), coal ash (a combustion by-product from power plants), co-compost (a mixture of 3 biosolids: 7 yard waste), and yard waste compost (mainly from leaves and branches of trees and shrubs, and grass clippings) with a soil-incorporated cover crop as the control. As a subsequent vegetable crop, okra was grown after the cover crops, alone or together with the organic soil amendments, had been incorporated. All of the cover crops, except sorghum sudangrass in 2002-03, significantly improved okra fruit yields and the total biomass production. Both cover crops and soil amendments can substantially improve nutrient uptake and distribution. The results suggest that cover crops and appropriate amounts of soil amendments can be used to improve soil fertility and okra yield without adverse environmental effects or risk of contamination of the fruit. Further field studies will be required to confirm these findings.

Plant uptake of radiocaesium from artificially contaminated soil monoliths covering major European soil types

International Nuclear Information System (INIS)

Waegeneers, Nadia; Sauras-Yera, Teresa; Thiry, Yves; Vallejo, V. Ramon; Smolders, Erik; Madoz-Escande, Chantal; Brechignac, Francois

2009-01-01

Uptake of 137 Cs was measured in different agricultural plant species (beans, lettuce, barley and ryegrass) grown in 5 undisturbed soil monoliths covering major European soil types. The first cultivation was made three years after soil contamination and plants were grown during 3 successive years. The plant-soil 137 Cs transfer factors varied maximally 12-fold among soils and 35-fold among species when grown on the same soil. Single correlations between transfer factors and soil properties were found, but they varied widely with plant type and can hardly be used as a predictive tool because of the few soils used. The variation of 137 Cs concentrations in plants among soils was related to differences in soil solution 137 Cs and K concentrations, consistent with previous observations in hydroponics and pot trials. Absolute values of transfer factors could not be predicted based on a model validated for pot trials. The 137 Cs activity concentration in soil solution decreased significantly (11- to 250-fold) for most soils in the 1997-1999 period and is partly explained by decreasing K in soil solution. Transfer factors of lettuce showed both increasing and decreasing trends between 2 consecutive years depending on soil type. The trends could be explained by the variation in 137 Cs and K concentrations in soil solution. It is concluded that differences in 137 Cs transfer factors among soils and trends in transfer factors as a function of time can be explained from soil solution composition, as shown previously for pot trials, although absolute values of transfer factors could not be predicted.

Health status of cows fed maize silage covered with oxo-biodegradable foil

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Piotr SZTERK

2017-11-01

Full Text Available In agricultural practice, silage production uses pure, low density polyethylene foil. This foil, after use, becomes farm waste, having a negative impact on the environment. Instead of conventional foil, an environmentally safe biodegradable foil can be used, made from naturally occurring polymers or from synthetic multiparticulates, easily degradable by microorganisms. Silage covered with this type of foil should be safe for animal health. The purpose of the study was to determine whether oxo-biodegradable film could be used instead of conventional film in agricultural practice, to produce silage that is safe for the cows' health. Dairy cows were fed a partly mixed ratio (PMR, the component of which was silage made of whole maize plants, covered with oxo-biodegradable foil. The cow blood serum was marked for content of: glucose, total protein, cholesterol, triacylglycerols and enzyme activity: aspartic and alanine aminotransferase, γ-glutamyl transferase, alkaline phosphatase and amylase. The total protein concentration in the serum of cows analyzed at the end of the experiment was higher than the commonly accepted normal values. The content of glucose, cholesterol, triacylglycerols and the activity of aspartate and alanine aminotransferase, γ-glutamyl transferase, alkaline phosphatase and amylase was within reference limits. Feeding of silage from whole maize plants covered withoxo-biodegradable foil did not negatively affect the biochemical indicators of the cows' blood serum. The silage proved to be safe for the cows' health.

Release of Phosphorus Forms from Cover Crop Residues in Agroecological No-Till Onion Production

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Rodolfo Assis de Oliveira

Full Text Available ABSTRACT Cover crops grown alone or in association can take up different amounts of phosphorus (P from the soil and accumulate it in different P-forms in plant tissue. Cover crop residues with a higher content of readily decomposed forms may release P more quickly for the next onion crop. The aim of this study was to evaluate the release of P forms from residues of single and mixed cover crops in agroecological no-till onion (Allium cepa L. production. The experiment was conducted in Ituporanga, Santa Catarina (SC, Brazil, in an Inceptisol, with the following treatments: weeds, black oat (Avena sativa L., rye (Secale cereale L., oilseed radish (Raphanus sativus L., oilseed radish + black oat, and oilseed radish + rye. Cover crops were sown in April 2013. In July 2013, plant shoots were cut close to the soil surface and part of the material was placed in litterbags. The bags were placed on the soil surface and residues were collected at 0, 15, and 45 days after deposition (DAD. Residues were dried and ground and P in the plant tissue was determined through chemical fractionation. The release of P contained in the tissue of cover crops depends not only on total P content in the tissue, but also on the accumulation of P forms and the quality of the residue in decomposition. The highest accumulation of P in cover crops occurred in the soluble inorganic P fraction, which is the fraction of fastest release in plants. Black oat had the highest initial release rate of soluble inorganic P, which became equal to the release rate of other cover crop residues at 45 DAD. Weeds released only half the amount of soluble inorganic P in the same period, despite accumulating a considerable amount of P in their biomass. The mixtures of oilseed radish + rye and oilseed radish + black oat showed higher release of P associated with RNA at 45 DAD in comparison to the single treatments.

Antioxidant, Cytotoxic Activities and Total Phenolic Content of Four Indonesian Medicinal Plants

Directory of Open Access Journals (Sweden)

Waras Nurcholis

2017-03-01

Full Text Available The crude ethanol extracts of four Indonesian medicinal plants namely Curcuma xanthorrhiza Roxb.,Phyllanthus niruri Linn., Andrographis paniculata Ness., and Curcuma aeruginosa Roxb. wereexamined for their antioxidant (radical scavenging activity using 2, 2-diphenyl-2-picrylhydrazyl(DPPH free radical and cytotoxicity using brine shrimp lethality test (BSLT. The total phenoliccontent was used the Folin-Ciocalteu method. IC50 values for DPPH radical scavenging activityranged from 14.5 to 178.5 μg/ml, with P. niruri having the lowest value and therefore the mostpotent, and C. aeruginosa having the highest value. LC50 values for BSLT ranged from 210.3 to593.2 μg/ml, with C. xanthorrhiza and A. paniculata having the lowest and highest values,respectively. The total phenolic content of the Indonesian plants ranged from 133.0 ±3.7 to863.3±54.7 mg tannic acid equivalent per 1 g extract, with C. aeruginosa and P. niruri having thelowest and highest values, respectively. A positive correlation between free radical scavengingactivity and the content of phenolic compounds was found in the four of Indonesian medicinal plants.

Production costs: U.S. hydroelectric power plants, 4th Edition

International Nuclear Information System (INIS)

Anon.

1993-01-01

The book provides 1991 operation and maintenance expenses for over 800 conventional and pumped-storage hydroelectric power plants. Report shows operator and plant name, plant year-in-service, installed capacity, 1991 net generation, O ampersand M expenses, total production costs and current plant capitalization. Fifty eight percent of the utility-owned hydroelectric plants in the US are covered by this report. Data diskette provides additional capital and production cost accounts and number of employees for each plant

Removal of two polycyclic musks in sewage treatment plants: Freely dissolved and total concentrations

NARCIS (Netherlands)

Artola-Garicano, E.; Borkent, I.; Hermens, J.L.M.; Vaes, W.H.J.

2003-01-01

In the current study, the removal of slowly degradable hydrophobic chemicals in sewage treatment plants (STPs) has been evaluated with emphasis on the combination of free and total concentration data. Free and total concentrations of two polycyclic musks were determined in each compartment of four

EHV transmission maintenance. A total asset strategy

International Nuclear Information System (INIS)

Bronsdon, J.A.N.

1996-01-01

For countries whose economies are rapidly expanding, the demand for power, and in particular electricity, is resulting in rapid expansions of the generation, transmission and distribution of electricity. This means that a new plant is being installed which, apart from some minor post commissioning problems, will be free from major maintenance for several years to come. Consequently, in such cases, maintenance is confined to basic annual shutdown checks and routine online monitoring. As equipment and plant age it is important to commence planning for additional maintenance over and above these basic annual checks; to monitor performance; to monitor faults and defects and to use that information to engineer out design faults, to influence current maintenance techniques and to influence future procurement specifications. Also, provided that sufficient information is available, informed decisions can be taken as to when a power plant should be decommissioned or refurbished. This process can be described as a total asset management strategy covering all decisions from procurement through to commissioning, ongoing maintenance, refurbishment, decommissioning and reappraisal of specifications for future procurement. Based upon the author's experience within the United Kingdom Electricity Supply industry, a total asset strategy will be proposed for EHV transmission plant that will optimise current and future expenditure while maximizing reliability and minimising downtime. 1 ref., 5 figs

Vegetation growth patterns on six rock-covered UMTRA Project disposal cells

International Nuclear Information System (INIS)

1992-02-01

This study assessed vegetation growth patterns, the potential impacts of vegetation growth on disposal cell cover integrity, and possible measures that could be taken to monitor and/or control plant growth, where necessary, on six Uranium Mill Tailings Remedial Action (UMTRA) Project rock-covered disposal cells. A large-scale invasion of volunteer plants was observed on the Shiprock and Burrell disposal cells. Plant growth at the South Clive, Green River, and Tuba City disposal cells was sparse except for the south rock apron and south slope of the Tuba City disposal cell, where windblown sand had filled up part of the rock cover and plant growth was observed. The rock-covered topslope of the Collins Ranch disposal cell was intentionally covered with topsoil and vegetated. Plant roots growing on the disposal cells are changing the characteristics of the cover by drying out the radon barrier, encouraging the establishment of soil-building processes in the bedding and radon barrier layers, creating channels in the radon barrier, and facilitating ecological succession, which could lead to the establishment of additional deep-rooted plants on the disposal cells. If left unchecked, plant roots would reach the tailings at the Burrell and Collins Ranch disposal cells within a few years, likely resulting in the transport of contaminants out of the cells

Distribution and variability of total mercury in snow cover-a case study from a semi-urban site in Poznań, Poland.

Science.gov (United States)

Siudek, Patrycja

2016-12-01

In the present paper, the inter-seasonal Hg variability in snow cover was examined based on multivariate statistical analysis of chemical and meteorological data. Samples of freshly fallen snow cover were collected at the semi-urban site in Poznań (central Poland), during 3-month field measurements in winter 2013. It was showed that concentrations of atmospherically deposited Hg were highly variable in snow cover, from 0.43 to 12.5 ng L -1 , with a mean value of 4.62 ng L -1 . The highest Hg concentration in snow cover coincided with local intensification of fossil fuel burning, indicating large contribution from various anthropogenic sources such as commercial and domestic heating, power generation plants, and traffic-related pollution. Moreover, the variability of Hg in collected snow samples was associated with long-range transport of pollutants, nocturnal inversion layer, low boundary layer height, and relatively low air temperature. For three snow episodes, Hg concentration in snow cover was attributed to southerly advection, suggesting significant contribution from the highly polluted region of Poland (Upper Silesia) and major European industrial hotspots. However, the peak Hg concentration was measured in samples collected during predominant N to NE advection of polluted air masses and after a relatively longer period without precipitation. Such significant contribution to the higher Hg accumulation in snow cover was associated with intensive emission from anthropogenic sources (coal combustion) and atmospheric conditions in this area. These results suggest that further measurements are needed to determine how the Hg transformation paths in snow cover change in response to longer/shorter duration of snow cover occurrence and to determine the interactions between mercury and absorbing carbonaceous aerosols in the light of climate change.

Effects of fire and three fire-fighting chemicals on main soil properties, plant nutrient content and vegetation growth and cover after 10 years

International Nuclear Information System (INIS)

Fernández-Fernández, M.; Gómez-Rey, M.X.; González-Prieto, S.J.

2015-01-01

The study addresses a knowledge-gap in the long-term ecological consequences of fire and fire-fighting chemicals. Ten years after a prescribed fire and the application of three fire-fighting chemicals, their effects on the soil–plant system were evaluated. Five treatments were established: unburnt soils (US) and burnt soils treated with water alone (BS), foaming agent (BS + Fo), Firesorb (BS + Fi) and ammonium polyphosphate (BS + Ap). Soils (0–2 cm depth) and foliar material of shrubs (Erica umbellata, Pterospartum tridentatum and Ulex micranthus) and trees (Pinus pinaster) were analysed for total N, δ 15 N, and soil-available and plant total macronutrients and trace elements. Soil pH, NH 4 + –N and NO 3 − –N; pine basal diameter and height; and shrub cover and height were also measured. Compared with US plots, burnt soils had less nitrates and more Mo. Although differences were not always significant, BS + Ap had the highest levels of soil available P, Na and Al. Plants from BS + Ap plots had higher values of δ 15 N (P. pinaster and E. umbellata), P (all species), Na (P. tridentatum and U. micranthus) and Mg (E. umbellata and P. tridentatum) than other treatments; while K in plants from BS + Ap plots was the highest among treatments for P. pinaster and the lowest for the shrubs. Pines in US plots were higher and wider than in burnt treatments, except for BS + Ap, where the tallest and widest trees were found, although half of them were either dead (the second highest mortality after BS + Fi) or had a distorted trunk. BS + Ap was the treatment with strongest effects on plants, showing E. umbellata the lowest coverage and height, P. tridentatum the highest coverage, U. micranthus one of the lowest coverages and being the only treatment where Genista triacanthos was absent. Consequently, it is concluded that both fire and ammonium polyphosphate application had significant effects on the soil–plant system after 10 years. - Highlights: • We hypothesized

Effect of winter cover crops on nematode population levels in north Florida.

Science.gov (United States)

Wang, K-H; McSorley, R; Gallaher, R N

2004-12-01

Two experiments were conducted in north-central Florida to examine the effects of various winter cover crops on plant-parasitic nematode populations through time. In the first experiment, six winter cover crops were rotated with summer corn (Zea mays), arranged in a randomized complete block design. The cover crops evaluated were wheat (Triticum aestivum), rye (Secale cereale), oat (Avena sativa), lupine (Lupinus angustifolius), hairy vetch (Vicia villosa), and crimson clover (Trifolium incarnatum). At the end of the corn crop in year 1, population densities of Meloidogyne incognita were lowest on corn following rye or oat (P rye or lupine was planted into field plots with histories of five tropical cover crops: soybean (Glycine max), cowpea (Vigna unguiculata), sorghum-sudangrass (Sorghum bicolor x S. sudanense), sunn hemp (Crotalaria juncea), and corn. Population densities of M. incognita and Helicotylenchus dihystera were affected by previous tropical cover crops (P cover crops present at the time of sampling. Plots planted to sunn hemp in the fall maintained the lowest M. incognita and H. dihystera numbers. Results suggest that winter cover crops tested did not suppress plant-parasitic nematodes effectively. Planting tropical cover crops such as sunn hemp after corn in a triple-cropping system with winter cover crops may provide more versatile nematode management strategies in northern Florida.

Using LIDAR and Quickbird Data to Model Plant Production and Quantify Uncertainties Associated with Wetland Detection and Land Cover Generalizations

Science.gov (United States)

Cook, Bruce D.; Bolstad, Paul V.; Naesset, Erik; Anderson, Ryan S.; Garrigues, Sebastian; Morisette, Jeffrey T.; Nickeson, Jaime; Davis, Kenneth J.

2009-01-01

Spatiotemporal data from satellite remote sensing and surface meteorology networks have made it possible to continuously monitor global plant production, and to identify global trends associated with land cover/use and climate change. Gross primary production (GPP) and net primary production (NPP) are routinely derived from the MOderate Resolution Imaging Spectroradiometer (MODIS) onboard satellites Terra and Aqua, and estimates generally agree with independent measurements at validation sites across the globe. However, the accuracy of GPP and NPP estimates in some regions may be limited by the quality of model input variables and heterogeneity at fine spatial scales. We developed new methods for deriving model inputs (i.e., land cover, leaf area, and photosynthetically active radiation absorbed by plant canopies) from airborne laser altimetry (LiDAR) and Quickbird multispectral data at resolutions ranging from about 30 m to 1 km. In addition, LiDAR-derived biomass was used as a means for computing carbon-use efficiency. Spatial variables were used with temporal data from ground-based monitoring stations to compute a six-year GPP and NPP time series for a 3600 ha study site in the Great Lakes region of North America. Model results compared favorably with independent observations from a 400 m flux tower and a process-based ecosystem model (BIOME-BGC), but only after removing vapor pressure deficit as a constraint on photosynthesis from the MODIS global algorithm. Fine resolution inputs captured more of the spatial variability, but estimates were similar to coarse-resolution data when integrated across the entire vegetation structure, composition, and conversion efficiencies were similar to upland plant communities. Plant productivity estimates were noticeably improved using LiDAR-derived variables, while uncertainties associated with land cover generalizations and wetlands in this largely forested landscape were considered less important.

Total Data Management System for the La Hague spent fuel reprocessing plants

International Nuclear Information System (INIS)

Chabert, J.; Coignaud, G.; Perot, J.P.; Fournier, W.; Silvain, B.

1991-01-01

Operation of the UP2 and UP3 reprocessing plants at La Hague, France, generates considerable data processing requirements. To meet these requirements, a Total Data Management System (TDMS) has been designed and installed to operate the biggest Ethernet industrial network in Europe. This network, called Haguenet, interconnects a large number of computers and user terminals. The TDMS' main operational functions are plant operation and production data management, maintenance data management, technical documents management and computer-aided design (CAD). Extensive experience was gained through the design and operation of the TDMS at La Hague. (author)

Planting Date and Seeding Rate Effects on Sunn Hemp Biomass and Nitrogen Production for a Winter Cover Crop

Directory of Open Access Journals (Sweden)

Kipling S. Balkcom

2011-01-01

Full Text Available Sunn hemp (Crotalaria juncea L. is a tropical legume that produces plant biomass and nitrogen (N quickly. Our objectives were to assess the growth of a new sunn hemp cultivar breed to produce seed in a temperate climate and determine the residual N effect on a rye (Secale cereale L. cover crop in east-central Alabama from 2007 to 2009. Plant populations, plant height, stem diameter, biomass production, and N content were determined for two sunn hemp planting dates, following corn (Zea mays L. and wheat (Triticum aestivum L. harvest, across different seeding rates (17, 34, 50, and 67 kg/ha. Rye biomass was measured the following spring. Sunn hemp biomass production was inconsistent across planting dates, but did relate to growing degree accumulation. Nitrogen concentrations were inversely related to biomass production, and subsequent N contents corresponded to biomass levels. Neither planting date nor seeding rate affected rye biomass production, but rye biomass averaged over both planting dates following wheat/sunn hemp averaged 43% and 33% greater than rye following fallow. Rye biomass following corn/sunn hemp was equivalent to fallow plots. Early planting dates are recommended for sunn hemp with seeding rates between 17 and 34 kg/ha to maximize biomass and N production.

Plant uptake of radiocaesium from artificially contaminated soil monoliths covering major European soil types

Energy Technology Data Exchange (ETDEWEB)

Waegeneers, Nadia [Laboratory for Soil and Water Management, Katholieke Universiteit Leuven, Kasteelpark Arenberg 20, B-3001 Heverlee (Belgium)], E-mail: nadia.waegeneers@agr.kuleuven.ac.be; Sauras-Yera, Teresa [Departament de Biologia Vegetal, Universitat de Barcelona, Av. Diagonal 645, 08028 Barcelona (Spain); Thiry, Yves [SCK.CEN, Radioecology Laboratory, Boeretang 200, B-2400 Mol (Belgium); Vallejo, V. Ramon [Departament de Biologia Vegetal, Universitat de Barcelona, Av. Diagonal 645, 08028 Barcelona (Spain); CEAM, Parque Tecnologico, Charles Darwin 14, 46980 Parterna (Spain); Smolders, Erik [Laboratory for Soil and Water Management, Katholieke Universiteit Leuven, Kasteelpark Arenberg 20, B-3001 Heverlee (Belgium); Madoz-Escande, Chantal; Brechignac, Francois [SERLAB, ISPN, Department for Environmental Protection, CE-Cadarache Batiment 159, Saint-Paul-lez-Durance Cedex 13108 (France)

2009-06-15

Uptake of {sup 137}Cs was measured in different agricultural plant species (beans, lettuce, barley and ryegrass) grown in 5 undisturbed soil monoliths covering major European soil types. The first cultivation was made three years after soil contamination and plants were grown during 3 successive years. The plant-soil {sup 137}Cs transfer factors varied maximally 12-fold among soils and 35-fold among species when grown on the same soil. Single correlations between transfer factors and soil properties were found, but they varied widely with plant type and can hardly be used as a predictive tool because of the few soils used. The variation of {sup 137}Cs concentrations in plants among soils was related to differences in soil solution {sup 137}Cs and K concentrations, consistent with previous observations in hydroponics and pot trials. Absolute values of transfer factors could not be predicted based on a model validated for pot trials. The {sup 137}Cs activity concentration in soil solution decreased significantly (11- to 250-fold) for most soils in the 1997-1999 period and is partly explained by decreasing K in soil solution. Transfer factors of lettuce showed both increasing and decreasing trends between 2 consecutive years depending on soil type. The trends could be explained by the variation in {sup 137}Cs and K concentrations in soil solution. It is concluded that differences in {sup 137}Cs transfer factors among soils and trends in transfer factors as a function of time can be explained from soil solution composition, as shown previously for pot trials, although absolute values of transfer factors could not be predicted.

Cover Crop (Rye) and No-Till System in Wisconsin

OpenAIRE

Alföldi, Thomas

2014-01-01

Erin Silva, University of Wisconsin, describes an organic no-till production technique using rye as cover crop to suppress weeds in the following production season. Using a roller-crimper, the overwintering rye is terminated at the time of cash crop planting, leaving a thick mat of plant residue on the soil surface. Soybeans are sown directly into the cover crop residue, allowing the cash crop to emerge through the terminated cover crop while suppressing weeds throughout the season. W...

Plant community variability on a small area in southeastern Montana

Science.gov (United States)

James G. MacCracken; Daniel W. Uresk; Richard M. Hansen

1984-01-01

Plant communities are inherently variable due to a number of environmental and biological forces. Canopy cover and aboveground biomass were determined for understory vegetation in plant communities of a prairie grassland-forest ecotone in southeastern Montana. Vegetation units were described using polar ordination and stepwise discriminant analysis. Nine of a total of...

Recent land cover history and nutrient retention in riparian wetlands

Science.gov (United States)

Hogan, D.M.; Walbridge, M.R.

2009-01-01

Wetland ecosystems are profoundly affected by altered nutrient and sediment loads received from anthropogenic activity in their surrounding watersheds. Our objective was to compare a gradient of agricultural and urban land cover history during the period from 1949 to 1997, with plant and soil nutrient concentrations in, and sediment deposition to, riparian wetlands in a rapidly urbanizing landscape. We observed that recent agricultural land cover was associated with increases in Nitrogen (N) and Phosphorus (P) concentrations in a native wetland plant species. Conversely, recent urban land cover appeared to alter receiving wetland environmental conditions by increasing the relative availability of P versus N, as reflected in an invasive, but not a native, plant species. In addition, increases in surface soil Fe content suggests recent inputs of terrestrial sediments associated specifically with increasing urban land cover. The observed correlation between urban land cover and riparian wetland plant tissue and surface soil nutrient concentrations and sediment deposition, suggest that urbanization specifically enhances the suitability of riparian wetland habitats for the invasive species Japanese stiltgrass [Microstegium vimenium (Trinius) A. Camus]. ?? 2009 Springer Science+Business Media, LLC.

Accumulation of total mercury and methylmercury in rice plants collected from different mining areas in China

International Nuclear Information System (INIS)

Meng, Mei; Li, Bing; Shao, Jun-juan; Wang, Thanh; He, Bin; Shi, Jian-bo; Ye, Zhi-hong; Jiang, Gui-bin

2014-01-01

A total of 155 rice plants were collected from ten mining areas in three provinces of China (Hunan, Guizhou and Guangdong), where most of mercury (Hg) mining takes place in China. During the harvest season, whole rice plants were sampled and divided into root, stalk and leaf, husk and seed (brown rice), together with soil from root zone. Although the degree of Hg contamination varied significantly among different mining areas, rice seed showed the highest ability for methylmercury (MeHg) accumulation. Both concentrations of total mercury (THg) and MeHg in rice plants were significantly correlated with Hg levels in soil, indicating soil is still an important source for both inorganic mercury (IHg) and MeHg in rice plants. The obvious discrepancy between the distribution patterns of THg and MeHg reflected different pathways of IHg and MeHg accumulation. Water soluble Hg may play more important role in MeHg accumulation in rice plants. -- Highlights: • Distribution patterns indicated different pathways of IHg and MeHg accumulation. • Soil is an important source for both THg and MeHg to rice plants. • Water soluble Hg may play more important role in MeHg accumulation in rice plants. -- The distribution patterns indicate different pathways of IHg and MeHg accumulation in rice plants

UMTRA project disposal cell cover biointrusion sensitivity assessment, Revision 1

International Nuclear Information System (INIS)

1995-10-01

This study provides an analysis of potential changes that may take place in a Uranium Mill Tailings Remedial Action (UMTRA) Project disposal cell cover system as a result of plant biointrusion. Potential changes are evaluated by performing a sensitivity analysis of the relative impact of root penetrations on radon flux out of the cell cover and/or water infiltration into the cell cover. Data used in this analysis consist of existing information on vegetation growth on selected cell cover systems and information available from published studies and/or other available project research. Consistent with the scope of this paper, no new site-specific data were collected from UMTRA Project sites. Further, this paper does not focus on the issue of plant transport of radon gas or other contaminants out of the disposal cell cover though it is acknowledged that such transport has the potential to be a significant pathway for contaminants to reach the environment during portions of the design life of a disposal cell where plant growth occurs. Rather, this study was performed to evaluate the effects of physical penetration and soil drying caused by plant roots that have and are expected to continue to grow in UMTRA Project disposal cell covers. An understanding of the biological and related physical processes that take place within the cover systems of the UMTRA Project disposal cells helps the U.S. Department of Energy (DOE) determine if the presence of a plant community on these cells is detrimental, beneficial, or of mixed value in terms of the cover system's designed function. Results of this investigation provide information relevant to the formulation of a vegetation control policy

Experimental tree removal in tallgrass prairie: variable responses of flora and fauna along a woody cover gradient.

Science.gov (United States)

Alford, Aaron L; Hellgren, Eric C; Limb, Ryan; Engle, David M

2012-04-01

Woody plant encroachment is a worldwide phenomenon in grassland and savanna systems whose consequence is often the development of an alternate woodland state. Theoretically, an alternate state may be associated with changes in system state variables (e.g., species composition) or abiotic parameter shifts (e.g., nutrient availability). When state-variable changes are cumulative, such as in woody plant encroachment, the probability of parameter shifts increases as system feedbacks intensify over time. Using a Before-After Control-Impact (BACI) design, we studied eight pairs of grassland sites undergoing various levels of eastern redcedar (Juniperus virginiana) encroachment to determine whether responses of flora and fauna to experimental redcedar removal differed according to the level of pretreatment redcedar cover. In the first year after removal, herbaceous plant species diversity and evenness, woody plant evenness, and invertebrate family richness increased linearly with pretreatment redcedar cover, whereas increases in small-mammal diversity and evenness were described by logarithmic trends. In contrast, increases in woody plant diversity and total biomass of terrestrial invertebrates were accentuated at levels of higher pretreatment cover. Tree removal also shifted small-mammal species composition toward a more grassland-associated assemblage. During the second year postremoval, increases in herbaceous plant diversity followed a polynomial trend, but increases in most other metrics did not vary along the pretreatment cover gradient. These changes were accompanied by extremely high growing-season precipitation, which may have homogenized floral and faunal responses to removal. Our results demonstrate that tree removal increases important community metrics among grassland flora and fauna within two years, with some responses to removal being strongly influenced by the stage of initial encroachment and modulated by climatic variability. Our results underscore the

Do cover crop mixtures have the same ability to suppress weeds as competitive monoculture cover crops?

Directory of Open Access Journals (Sweden)

Brust, Jochen

2014-02-01

Full Text Available An increasing number of farmers use cover crop mixtures instead of monoculture cover crops to improve soil and crop quality. However, only little information is available about the weed suppression ability of cover crop mixtures. Therefore, two field experiments were conducted in Baden-Württemberg between 2010 and 2012, to compare growth and weed suppression of monoculture cover crops and cover crop mixtures. In the first experiment, heterogeneous results between yellow mustard and the cover crop mixture occurred. For further research, a field experiment was conducted in 2012 to compare monocultures of yellow mustard and hemp with three cover crop mixtures. The evaluated mixtures were: “MELO”: for soil melioration; “BETA”: includes only plant species with no close relation to main cash crops in Central Europe and “GPS”: for usage as energy substrate in spring. Yellow mustard, MELO, BETA and GPS covered 90% of the soil in less than 42 days and were able to reduce photosynthetically active radiation (PAR on soil surface by more than 96% after 52 days. Hemp covered 90% of the soil after 47 days and reduced PAR by 91% after 52 days. Eight weeks after planting, only BETA showed similar growth to yellow mustard which produced the highest dry matter. The GPS mixture had comparatively poor growth, while MELO produced similar dry matter to hemp. Yellow mustard, MELO and BETA reduced weed growth by 96% compared with a no cover crop control, while hemp and GPS reduced weeds by 85% and 79%. In spring, weed dry matter was reduced by more than 94% in plots with yellow mustard and all mixtures, while in hemp plots weeds were only reduced by 71%. The results suggest that the tested cover crop mixtures offer similar weed suppression ability until spring as the monoculture of the competitive yellow mustard.

Crecimiento de Plantas de Remolacha (Beta vulgaris L. var. Crosby Egipcia Bajo Coberturas de Color Growth of Beet (Beta vulgaris L. var. Crosby Egipcia under Colored Covers

Directory of Open Access Journals (Sweden)

Fánor Casierra-Posada

2011-12-01

Full Text Available La respuesta de las plantas a diferente color en la iluminación, se atribuye a fotorreceptores que conducen a diversas expresiones fenotípicas en diferentes niveles y etapas del desarrollo vegetal. Para determinar si el color de iluminación en que se cultivan las plantas de remolacha (Beta vulgaris L. var. Crosby Egipcia, afecta su crecimiento, rendimiento y calidad, se realizó en Duitama -; Colombia, un estudio bajo coberturas de color azul, rojo o transparente. Para conseguir los colores se colocaron películas de polietileno, 65 cm por encima del cultivo, dejando un control a plena exposición. Las plantas cubiertas con la película roja presentaron mejor calidad de raíz basada en el diámetro, sólidos solubles totales y peso fresco y seco en comparación con las que crecieron bajo cobertura azul, transparente o los controles. Las plantas bajo la cobertura roja mostraron valores mayores de área foliar y peso seco total. Los valores más bajos se presentaron en plantas bajo la cubierta azul. La radiación monocromática inducida por las coberturas alteró también la distribución de materia seca en los órganos de la planta. La calidad de la luz alteró el crecimiento y la calidad del producto a cosechar en remolacha, por los efectos sobre los fotorreceptores que alteran los patrones de crecimiento.Plant responses to different colors of illumination are attributed to different photoreceptors which operate as light-induced initiators of signalling pathways leading to varying phenotypic expressions at various levels and stages of plant development. To determine whether the color of illumination under which plants are grown, affects the growth, yield and the quality of harvested product, beet plants (Beta vulgaris L. var. Crosby Egipcia were grown under either blue-enriched, red-enriched, or transparent covers in Duitama -Colombia. To get colors, red, blue and transparent polyethylene films were expanded 65 cm above crop, leaving an

Total loss of the covering of a metallic stent during esophageal leak treatment

Directory of Open Access Journals (Sweden)

J.J. Villarreal-Galvan

2013-01-01

Full Text Available A 41-year-old man underwent a Heller myotomy due to achalasia. An unexpected puncture in the esophageal wall was identified during the procedure. A partially covered 15 cm stent (PSEMS (UltraFlex was placed at the mucosal defect. It was removed 26 days later and the endoscopic image showed esophageal tissue embedded in the covered portion of the stent. PSEMS covering loss is a rare complication that can have serious consequences.

Phytoremediation of hydrocarbon-contaminated soil using plants adapted to western Canadian climate

International Nuclear Information System (INIS)

Robson, D.B.

2003-01-01

Phytoremediation relies on the use of plants for in-situ treatment of hydrocarbon contaminated soils. It is based on relationships between plants, microorganisms and the environment. The advantages of the process are its low cost and minimal soil disturbance. Phytoremediation has not been widely implemented in Canada because only a few native or non-native plant species have been tested for hydrocarbon tolerance or degradation ability. More studies are needed to fully understand why some plants are more tolerant of hydrocarbons than others, and whether tolerant species increase hydrocarbon degradation. In this study, several field and growth chamber experiments were conducted to examine hydrocarbon tolerance in plants. Hydrocarbon contaminated field plots had higher soil pH, carbon to nitrogen ratio and bare ground, lower total nitrogen, available phosphorous and litter cover. The mean diversity at the uncontaminated sites was 0.52. It was 0.45 at the contaminated sites. Mean species similarity between contaminated and uncontaminated sites was 31.1 per cent and cover similarity was 22.2 per cent. The common plants in the contaminated field included kochia, wild barley, salt grass, bluegrass, and wheatgrass. The plants that formed most plant cover on contaminated plots were non-mycorrhizal, self-pollinating, and large seeded. The species with the highest survival after 5 weeks in hydrocarbon contaminated soils included one native and 4 non-native grasses, 2 native and 3 non-native legumes and 2 native forbs. All plants (with the exception of Indian breadroot) grown in hydrocarbon contaminated potting soil had lower total biomass and lower growth rates compared to the control

Phytoremediation of hydrocarbon-contaminated soil using plants adapted to western Canadian climate

Energy Technology Data Exchange (ETDEWEB)

Robson, D.B.

2003-07-01

Phytoremediation relies on the use of plants for in-situ treatment of hydrocarbon contaminated soils. It is based on relationships between plants, microorganisms and the environment. The advantages of the process are its low cost and minimal soil disturbance. Phytoremediation has not been widely implemented in Canada because only a few native or non-native plant species have been tested for hydrocarbon tolerance or degradation ability. More studies are needed to fully understand why some plants are more tolerant of hydrocarbons than others, and whether tolerant species increase hydrocarbon degradation. In this study, several field and growth chamber experiments were conducted to examine hydrocarbon tolerance in plants. Hydrocarbon contaminated field plots had higher soil pH, carbon to nitrogen ratio and bare ground, lower total nitrogen, available phosphorous and litter cover. The mean diversity at the uncontaminated sites was 0.52. It was 0.45 at the contaminated sites. Mean species similarity between contaminated and uncontaminated sites was 31.1 per cent and cover similarity was 22.2 per cent. The common plants in the contaminated field included kochia, wild barley, salt grass, bluegrass, and wheatgrass. The plants that formed most plant cover on contaminated plots were non-mycorrhizal, self-pollinating, and large seeded. The species with the highest survival after 5 weeks in hydrocarbon contaminated soils included one native and 4 non-native grasses, 2 native and 3 non-native legumes and 2 native forbs. All plants (with the exception of Indian breadroot) grown in hydrocarbon contaminated potting soil had lower total biomass and lower growth rates compared to the control.

Vegetative, productive and qualitative performance of grapevine "Cabernet Sauvignon" according to the use of winter cover crops

Directory of Open Access Journals (Sweden)

Jean Carlos Bettoni

Full Text Available ABSTRACT To study the effect of winter cover crops on the vegetative, productive and qualitative behavior of "Cabernet Sauvignon" grapevines, an experiment was conducted in two wine harvests by sowing different species of winter cover crops and additional treatments with manual weeding and mechanical mowing in an experimental vineyard located at the Experimental Station of Epagri in Videira, state of Santa Catarina, Brazil. Plant attributes of the grapevine, such as number of rods and weight of pruned material and number of branches per plant. At the time of skin color change, petioles of recently matured leaves were collected for analysis of the levels of N, P, K, Ca, Mg, Fe, Mn, Zn and B. Moments before harvest, 100 grape berries were collected randomly to determine the total soluble solids, titratable acidity and pH. At harvest, the number of bunches per branch, the number and mass of clusters per plant and the average mass of clusters per plot were determined. Fresh and dry matter yields of the cover crop and weed plants were also determined when coverage reached full bloom. The winter cover crops did not alter the yield and quality of "Cabernet Sauvignon" grapes and showed no differences from each other for the management of spontaneous vegetation by hand weeding or mechanical mowing. Rye and ryegrass are effective alternatives for weed control alternatives. The species of white and red clover present difficulty in initial establishment, producing a small amount of biomass.

A new NDVI measure that overcomes data sparsity in cloud-covered regions predicts annual variation in ground-based estimates of high arctic plant productivity

Science.gov (United States)

Rune Karlsen, Stein; Anderson, Helen B.; van der Wal, René; Bremset Hansen, Brage

2018-02-01

Efforts to estimate plant productivity using satellite data can be frustrated by the presence of cloud cover. We developed a new method to overcome this problem, focussing on the high-arctic archipelago of Svalbard where extensive cloud cover during the growing season can prevent plant productivity from being estimated over large areas. We used a field-based time-series (2000-2009) of live aboveground vascular plant biomass data and a recently processed cloud-free MODIS-Normalised Difference Vegetation Index (NDVI) data set (2000-2014) to estimate, on a pixel-by-pixel basis, the onset of plant growth. We then summed NDVI values from onset of spring to the average time of peak NDVI to give an estimate of annual plant productivity. This remotely sensed productivity measure was then compared, at two different spatial scales, with the peak plant biomass field data. At both the local scale, surrounding the field data site, and the larger regional scale, our NDVI measure was found to predict plant biomass (adjusted R 2 = 0.51 and 0.44, respectively). The commonly used ‘maximum NDVI’ plant productivity index showed no relationship with plant biomass, likely due to some years having very few cloud-free images available during the peak plant growing season. Thus, we propose this new summed NDVI from onset of spring to time of peak NDVI as a proxy of large-scale plant productivity for regions such as the Arctic where climatic conditions restrict the availability of cloud-free images.

Does a decade of elevated [CO2] affect a desert perennial plant community?

Science.gov (United States)

Newingham, Beth A; Vanier, Cheryl H; Kelly, Lauren J; Charlet, Therese N; Smith, Stanley D

2014-01-01

Understanding the effects of elevated [CO2 ] on plant community structure is crucial to predicting ecosystem responses to global change. Early predictions suggested that productivity in deserts would increase via enhanced water-use efficiency under elevated [CO2], but the response of intact arid plant communities to elevated [CO2 ] is largely unknown. We measured changes in perennial plant community characteristics (cover, species richness and diversity) after 10 yr of elevated [CO2] exposure in an intact Mojave Desert community at the Nevada Desert Free-Air CO2 Enrichment (FACE) Facility. Contrary to expectations, total cover, species richness, and diversity were not affected by elevated [CO2]. Over the course of the experiment, elevated [CO2] had no effect on changes in cover of the evergreen C3 shrub, Larrea tridentata; alleviated decreases in cover of the C4 bunchgrass, Pleuraphis rigida; and slightly reduced the cover of C3 drought-deciduous shrubs. Thus, we generally found no effect of elevated [CO2] on plant communities in this arid ecosystem. Extended drought, slow plant growth rates, and highly episodic germination and recruitment of new individuals explain the lack of strong perennial plant community shifts after a decade of elevated [CO2]. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

Fuel element transport container with a removable cover

International Nuclear Information System (INIS)

Dannehl, G.; Fink, W.; Haenle, G.

1980-01-01

The cover of the fuel element transport container is removably fixed with screws on a flange as mechanical loads have to be expected during the transfer to the disposal plant. A ring-shaped or star-shaped clamping device grips over the cover. It has a clamp claw to lock the cover and permits unscrewing without unlocking the cover. (DG) [de

Assessing winter cover crop nutrient uptake efficiency using a water quality simulation model

Science.gov (United States)

Yeo, In-Young; Lee, Sangchui; Sadeghi, Ali M.; Beeson, Peter C.; Hively, W. Dean; McCarty, Greg W.; Lang, Megan W.

2013-01-01

Winter cover crops are an effective conservation management practice with potential to improve water quality. Throughout the Chesapeake Bay Watershed (CBW), which is located in the Mid-Atlantic US, winter cover crop use has been emphasized and federal and state cost-share programs are available to farmers to subsidize the cost of winter cover crop establishment. The objective of this study was to assess the long-term effect of planting winter cover crops at the watershed scale and to identify critical source areas of high nitrate export. A physically-based watershed simulation model, Soil and Water Assessment Tool (SWAT), was calibrated and validated using water quality monitoring data and satellite-based estimates of winter cover crop species performance to simulate hydrological processes and nutrient cycling over the period of 1991–2000. Multiple scenarios were developed to obtain baseline information on nitrate loading without winter cover crops planted and to investigate how nitrate loading could change with different winter cover crop planting scenarios, including different species, planting times, and implementation areas. The results indicate that winter cover crops had a negligible impact on water budget, but significantly reduced nitrate leaching to groundwater and delivery to the waterways. Without winter cover crops, annual nitrate loading was approximately 14 kg ha−1, but it decreased to 4.6–10.1 kg ha−1 with winter cover crops resulting in a reduction rate of 27–67% at the watershed scale. Rye was most effective, with a potential to reduce nitrate leaching by up to 93% with early planting at the field scale. Early planting of winter cover crops (~30 days of additional growing days) was crucial, as it lowered nitrate export by an additional ~2 kg ha−1 when compared to late planting scenarios. The effectiveness of cover cropping increased with increasing extent of winter cover crop implementation. Agricultural fields with well-drained soils

Effects of fire and three fire-fighting chemicals on main soil properties, plant nutrient content and vegetation growth and cover after 10 years

Energy Technology Data Exchange (ETDEWEB)

Fernández-Fernández, M., E-mail: mariafernandez@iiag.csic.es; Gómez-Rey, M.X., E-mail: mxgomez@iiag.csic.es; González-Prieto, S.J., E-mail: serafin@iiag.csic.es

2015-05-15

The study addresses a knowledge-gap in the long-term ecological consequences of fire and fire-fighting chemicals. Ten years after a prescribed fire and the application of three fire-fighting chemicals, their effects on the soil–plant system were evaluated. Five treatments were established: unburnt soils (US) and burnt soils treated with water alone (BS), foaming agent (BS + Fo), Firesorb (BS + Fi) and ammonium polyphosphate (BS + Ap). Soils (0–2 cm depth) and foliar material of shrubs (Erica umbellata, Pterospartum tridentatum and Ulex micranthus) and trees (Pinus pinaster) were analysed for total N, δ{sup 15}N, and soil-available and plant total macronutrients and trace elements. Soil pH, NH{sub 4}{sup +}–N and NO{sub 3}{sup −}–N; pine basal diameter and height; and shrub cover and height were also measured. Compared with US plots, burnt soils had less nitrates and more Mo. Although differences were not always significant, BS + Ap had the highest levels of soil available P, Na and Al. Plants from BS + Ap plots had higher values of δ{sup 15}N (P. pinaster and E. umbellata), P (all species), Na (P. tridentatum and U. micranthus) and Mg (E. umbellata and P. tridentatum) than other treatments; while K in plants from BS + Ap plots was the highest among treatments for P. pinaster and the lowest for the shrubs. Pines in US plots were higher and wider than in burnt treatments, except for BS + Ap, where the tallest and widest trees were found, although half of them were either dead (the second highest mortality after BS + Fi) or had a distorted trunk. BS + Ap was the treatment with strongest effects on plants, showing E. umbellata the lowest coverage and height, P. tridentatum the highest coverage, U. micranthus one of the lowest coverages and being the only treatment where Genista triacanthos was absent. Consequently, it is concluded that both fire and ammonium polyphosphate application had significant effects on the soil–plant system after 10 years

Diverse urban plantings managed with sufficient resource availability can increase plant productivity and arthropod diversity

Directory of Open Access Journals (Sweden)

Jonathon eMuller

2014-10-01

Full Text Available Buildings structures and surfaces are explicitly being used to grow plants, and these ‘urban plantings’ are typically designed for aesthetic value. Urban plantings also have the potential to contribute significant ‘ecological values’ by increasing urban habitat for animals such as arthropods and by increasing plant productivity. In this study, we evaluated how the provision of these additional ecological values is affected by plant species richness; the availability of essential resources for plants, such as water, light, space; and soil characteristics. We sampled 33 plantings located on the exterior of three buildings in the urban centre of Brisbane, Australia (subtropical climatic region over two, six week sampling periods characterised by different temperature and rainfall conditions. Plant cover was estimated as a surrogate for productivity as destructive sampling of biomass was not possible. We measured weekly light levels (photosynthetically active radiation, plant CO2 assimilation, soil CO2 efflux, and arthropod diversity.Differences in plant cover were best explained by a three-way interaction of plant species richness, management water regime and sampling period. As the richness of plant species increased in a planter, productivity and total arthropod richness also increased significantly - likely due to greater habitat heterogeneity and quality. Overall we found urban plantings can provide additional ecological values if essential resources are maintained within a planter such as water, light and soil temperature. Diverse urban plantings that are managed with these principles in mind can contribute to the attraction of diverse arthropod communities, and lead to increased plant productivity within a dense urban context.

Effects Total Solar Eclipse to Nasty Behaviour of the Several Legume Plants as a Result Student Research

Science.gov (United States)

Anggraeni, S.; Diana, S.; Supriatno, B.

2017-09-01

Some group students of plant Physiology course have given task to do free inquiry. They investigated of the nasty behaviour of several legume plants in response to changes in light during the partial solar eclipse that occurred at March 9, 2016. The investigation carried out in UPI Bandung, West Java, Indonesia, which is in the penumbra region of a total solar eclipse with the location coordinates of latitude: -6.86105, longitude: 07.59071, S 6057’ 37.53553 “and E 107035’ 24.29141”. They were measuring the movement of opening leaves every ten minutes at the beginning of the start until the end of the eclipse compared with the behaviour without eclipsing. Influence is expressed by comparing the leaf opening movement (measured in the form of leaf angular) at the time of the eclipse with a normal day. Each group was observed for one plant of the legume, there are: Mimosa pudica, Bauhinia purpurea, Caesalpinia pulcherrima, and Arachis pintoi. The results showed that the changes in leaf angular in plants Mimosa pudica, Caesalpinia pulcherrima, and Arachis pintoi differently significant, except for Bauhinia purpurea. In conclusion, the total solar eclipse in the penumbra area affects the movement of some nasty legume plants. It is recommended to conduct a study of the nasty behaviour of legume plants in the area umbra in the path of a total solar eclipse.

Assessing winter cover crop nutrient uptake efficiency using a water quality simulation model

Science.gov (United States)

Yeo, I.-Y.; Lee, S.; Sadeghi, A. M.; Beeson, P. C.; Hively, W. D.; McCarty, G. W.; Lang, M. W.

2014-12-01

Winter cover crops are an effective conservation management practice with potential to improve water quality. Throughout the Chesapeake Bay watershed (CBW), which is located in the mid-Atlantic US, winter cover crop use has been emphasized, and federal and state cost-share programs are available to farmers to subsidize the cost of cover crop establishment. The objective of this study was to assess the long-term effect of planting winter cover crops to improve water quality at the watershed scale (~ 50 km2) and to identify critical source areas of high nitrate export. A physically based watershed simulation model, Soil and Water Assessment Tool (SWAT), was calibrated and validated using water quality monitoring data to simulate hydrological processes and agricultural nutrient cycling over the period of 1990-2000. To accurately simulate winter cover crop biomass in relation to growing conditions, a new approach was developed to further calibrate plant growth parameters that control the leaf area development curve using multitemporal satellite-based measurements of species-specific winter cover crop performance. Multiple SWAT scenarios were developed to obtain baseline information on nitrate loading without winter cover crops and to investigate how nitrate loading could change under different winter cover crop planting scenarios, including different species, planting dates, and implementation areas. The simulation results indicate that winter cover crops have a negligible impact on the water budget but significantly reduce nitrate leaching to groundwater and delivery to the waterways. Without winter cover crops, annual nitrate loading from agricultural lands was approximately 14 kg ha-1, but decreased to 4.6-10.1 kg ha-1 with cover crops resulting in a reduction rate of 27-67% at the watershed scale. Rye was the most effective species, with a potential to reduce nitrate leaching by up to 93% with early planting at the field scale. Early planting of cover crops (~ 30

Gross and net land cover changes in the main plant functional types derived from the annual ESA CCI land cover maps (1992-2015)

Science.gov (United States)

Li, Wei; MacBean, Natasha; Ciais, Philippe; Defourny, Pierre; Lamarche, Céline; Bontemps, Sophie; Houghton, Richard A.; Peng, Shushi

2018-01-01

Land-use and land-cover change (LULCC) impacts local energy and water balance and contributes on global scale to a net carbon emission to the atmosphere. The newly released annual ESA CCI (climate change initiative) land cover maps provide continuous land cover changes at 300 m resolution from 1992 to 2015, and can be used in land surface models (LSMs) to simulate LULCC effects on carbon stocks and on surface energy budgets. Here we investigate the absolute areas and gross and net changes in different plant functional types (PFTs) derived from ESA CCI products. The results are compared with other datasets. Global areas of forest, cropland and grassland PFTs from ESA are 30.4, 19.3 and 35.7 million km2 in the year 2000. The global forest area is lower than that from LUH2v2h (Hurtt et al., 2011), Hansen et al. (2013) or Houghton and Nassikas (2017) while cropland area is higher than LUH2v2h (Hurtt et al., 2011), in which cropland area is from HYDE 3.2 (Klein Goldewijk et al., 2016). Gross forest loss and gain during 1992-2015 are 1.5 and 0.9 million km2 respectively, resulting in a net forest loss of 0.6 million km2, mainly occurring in South and Central America. The magnitudes of gross changes in forest, cropland and grassland PFTs in the ESA CCI are smaller than those in other datasets. The magnitude of global net cropland gain for the whole period is consistent with HYDE 3.2 (Klein Goldewijk et al., 2016), but most of the increases happened before 2004 in ESA and after 2007 in HYDE 3.2. Brazil, Bolivia and Indonesia are the countries with the largest net forest loss from 1992 to 2015, and the decreased areas are generally consistent with those from Hansen et al. (2013) based on Landsat 30 m resolution images. Despite discrepancies compared to other datasets, and uncertainties in converting into PFTs, the new ESA CCI products provide the first detailed long-term time series of land-cover change and can be implemented in LSMs to characterize recent carbon dynamics

Determination of total As in onion plants growing in contaminated substrates by total reflection X-ray fluorescence

International Nuclear Information System (INIS)

Lue-Meru Marco Parra

2011-01-01

The onion (Allium cepa L.) is one of the most important cultivars in the world and its production level occupies the second place in Venezuela. It becomes important to develop analytical procedures for arsenic determination and to study the effect of this element on the cultures, as well the absorption, transport and translocation processes. A TXRF method for As determination in onions was developed. Two treatments were applied to the onion plants, As contaminated and control. The contaminant was added to the plants to an amount of 100 μg, in a single time 3 weeks after the transplant of plantlets. The green leaves bulbs, and roots together with the stems were separated 45 days after transplant and analyzed by TXRF and HG-AAS for total Arsenic determination. A good agreement was found between these two techniques, demonstrating the accuracy of the TXRF procedure. It was found that the highest concentration corresponded to the root and stems (37 ± 31 μg g -1 ), followed by the bulbs (11 ± 7 μg g -1 ), being the smallest level found in the green leaves (4 ± 3 μg g -1 ). At low As contamination levels of 0.25 μg g -1 , a risk for translocation of the toxic element to the edible parts of the onion plants exists. At this level the normal development of the plant is not affected, being the only exception the root length, which is significantly higher in the contaminated treatment. (author)

Plant life form based habitat monitoring in a European landscape framework for early warning of changes in land cover and biodiversity

DEFF Research Database (Denmark)

Brandt, Jesper; Olsen, Martin; Bloch-Petersen, Margit

and habitat composition and quality. The focus on essential features of the habitat that can be expressed easily and quantitatively for identification and mapping of small but significant changes at a landscape level has resulted in the reintroduction of Raunkiaers plant life form concept from 1907...... of agricultural land use, general land cover and tree and shrub cover of small biotopes), it has not been difficult to integrate the BioHab framework in the SBMP-monitoring system, thus permitting the monitoring system to deliver an additional important European perspective with only very limited extra resources...

Herbivory and dominance shifts among exotic and congeneric native plant species during plant community establishment

DEFF Research Database (Denmark)

Engelkes, Tim; Meisner, Annelein; Morriën, Elly

2016-01-01

in a riparian ecosystem during early establishment of invaded communities. We planted ten plant communities each consisting of three individuals of each of six exotic plant species as well as six phylogenetically related natives. Exotic plant species were selected based on a rapid recent increase in regional...... abundance, the presence of a congeneric native species, and their co-occurrence in the riparian ecosystem. All plant communities were covered by tents with insect mesh. Five tents were open on the leeward side to allow herbivory. The other five tents were completely closed in order to exclude insects...... and vertebrates. Herbivory reduced aboveground biomass by half and influenced which of the plant species dominated the establishing communities. Exposure to herbivory did not reduce the total biomass of natives more than that of exotics, so aboveground herbivory did not selectively enhance exotics during...

Effect of length of interval between cereal rye cover crop termination and corn planting on seedling root disease and corn growth

Science.gov (United States)

Cereal rye cover crops terminated immediately before corn planting can sometimes reduce corn population, early growth, and yield. We hypothesized that cereal rye may act as a green bridge for corn pathogens and may increase corn seedling root disease. A field experiment was conducted over two years ...

Estimation of Evapotranspiration from Fields with and without Cover Crops Using Remote Sensing and in situ Methods

Directory of Open Access Journals (Sweden)

Christopher Hay

2012-11-01

Full Text Available Estimation of actual evapotranspiration (ETa based on remotely sensed imagery is very valuable in agricultural regions where ETa rates can vary greatly from field to field. This research utilizes the image processing model METRIC (Mapping Evapotranspiration at high Resolution with Internalized Calibration to estimate late season, post-harvest ETa rates from fields with a cover crop planted after a cash crop (in this case, a rye/radish/pea mixture planted after spring wheat. Remotely sensed EToF (unit-less fraction of grass-based reference ET, ETo maps were generated using Erdas Imagine software for a 260 km2 area in northeastern South Dakota, USA. Meteorological information was obtained from a Bowen-Ratio Energy Balance System (BREBS located within the image. Nine image dates were used for the growing season, from May through October. Five of those nine were captured during the cover crop season. METRIC was found to successfully differentiate between fields with and without cover crops. In a blind comparison, METRIC compared favorably with the estimated ETa rates found using the BREBS (ETλE, with a difference in total estimated ETa for the cover crop season of 7%.

Secondary succession of nematodes in power plant ash dumps reclaimed by covering with turf

Energy Technology Data Exchange (ETDEWEB)

Dmowska, E.; Ilieva-Makulec, K. [Polish Academy of Science, Lomianki (Poland)

2006-11-15

An analysis of successive changes in nematode assemblages in reclaimed waste area offers information about the sensitivity of species or groups of nematodes to specific conditions and ability to colonise new habitats. The study was carried in ash dumps being a by-product of the combustion of hard coal and reclaimed by covering with mineral turf (light loam warp soil) or organic turf (alder peat). In the first 3 years of reclamation diversity of nematodes was low, especially in, the dump covered with mineral turf - Shannon diversity index below 3. Later on the value of Shannon index increased and did not differ from those recorded for meadows in Poland. In the ash dump, reclaimed for a longer time period (8-11 years), the contribution of K strategist species was higher than in the dumps reclaimed for a shorter time period (2-5 years). At the earlier stages of succession bacterivores Acrobeloides, and two fungivores Aphelenchoides and Aphelenchus, predominated. In the ash dump reclaimed longer the dominance of these three genera decreased and some plant feeders achieved high contribution ({gt} 30%). The composition of nematode communities depended. significantly on the period of reclamation, but did not depend either on the soil moisture and pH or on season.

Winter rye cover crop effect on corn seedling pathogens

Science.gov (United States)

Cover crops have been grown successfully in Iowa, but sometimes a cereal rye cover crop preceding corn can reduce corn yields. Our research examines the effect of a rye cover crop on infections of the succeeding corn crop by soil fungal pathogens. Plant measurements included: growth stage, height, r...

Landfill cover revegetation using organic amendments and cobble mulch in the arid southwest

Energy Technology Data Exchange (ETDEWEB)

AGUILAR,RICHARD; DWYER,STEPHEN F.; REAVIS,BRUCE A.; NEWMAN,GRETCHEN CARR; LOFTIN,SAMUEL R.

2000-02-01

biomass production in the irrigated control plots over that produced in the non-irrigated control plots. This surprising result was probably due to the cumulative effects of other factors that influenced the initial establishment and production of plants in the plots (e.g., plant species competition, seed germination delay times, differences in nutrient release and availability). Variation within individual plots, and among the three replicate plots associated with each treatment, rendered many of the recorded differences in vegetation establishment and production statistically insignificant. However, after two complete growing seasons the highest total plant foliar cover and the greatest biomass production and plant species diversity occurred in the cobble-mulched plots. These results suggest that cobble-mulch may be the desired amendment in re-vegetated arid landfill covers if the principal objectives are to quickly establish vegetation cover, stabilize the site from erosion, and increase water usage by plants, thereby reducing the potential for leaching and contaminant movement from the landfill's waste-bearing zone.

Assessment of the effect of land use /land cover changes on total runoff from Ofu River catchment in Nigeria

Directory of Open Access Journals (Sweden)

Meshach Ileanwa Alfa

2018-04-01

Full Text Available The total runoff from a catchment is dependednt on both the soil characteristics and the land use/land cover (LULC type. This study was conducted to examine the effect of changes in land cover on the total runoff from Ofu River Catchment in Nigeria. Classified Landsat imageries of 1987, 2001 and 2016 in combination with the soil map extracted from the Digital Soil Map of the World was used to estimate the runoff curve number for 1987, 2001 and 2016. The runoff depth for 35 years daily rainfall data was estimated using Natura Resource Conservation Services Curve Number (NRCS-CN method. The runoff depths obtained for the respective years were subjected to a one-way analysis of variance at 95% level of significance. P-value < 0.05 was taken as statistically significant. Runoff curve numbers obtained for 1987, 2001 and 2016 were 61.83, 63.26 and 62.79 respectively. The effects of the changes in LULC for 1987-2001, 2001-2016 and 1987-2016 were statistically significant (P<0.001 at 95% confident interval.  The average change in runoff depths were 79.81%, -11.10% and 48.09% respectively for 1987-2001, 2001-2016 and 1987-2016. The study concluded that the changes in LULC of the catchment had significant effect on the runoff from the catchment.

Screening of immunomodulatory activity of total and protein extracts of some Moroccan medicinal plants.

Science.gov (United States)

Daoudi, Abdeljlil; Aarab, Lotfi; Abdel-Sattar, Essam

2013-04-01

Herbal and traditional medicines are being widely used in practice in many countries for their benefits of treating different ailments. A large number of plants in Morocco were used in folk medicine to treat immune-related disorders. The objective of this study is to evaluate the immunomodulatory activity of protein extracts (PEs) of 14 Moroccan medicinal plants. This activity was tested on the proliferation of immune cells. The prepared total and PEs of the plant samples were tested using MTT (3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide) assay on the splenocytes with or without stimulation by concanavalin-A (Con-A), a mitogenic agent used as positive control. The results of this study indicated different activity spectra. Three groups of activities were observed. The first group represented by Citrullus colocynthis, Urtica dioica, Elettaria cardamomum, Capparis spinosa and Piper cubeba showed a significant immunosuppressive activity. The second group that showed a significant immunostimulatory activity was represented by Aristolochia longa, Datura stramonium, Marrubium vulgare, Sinapis nigra, Delphynium staphysagria, Lepidium sativum, Ammi visnaga and Tetraclinis articulata. The rest of the plant extracts did not alter the proliferation induced by Con-A. This result was more important for the PE than for the total extract. In conclusion, this study revealed an interesting immunomodulating action of certain PEs, which could explain their traditional use. The results of this study may also have implications in therapeutic treatment of infections, such as prophylactic and adjuvant with cancer chemotherapy.

Cover Crops Effects on Soil Chemical Properties and Onion Yield

Directory of Open Access Journals (Sweden)

Rodolfo Assis de Oliveira

2016-01-01

Full Text Available ABSTRACT Cover crops contribute to nutrient cycling and may improve soil chemical properties and, consequently, increase crop yield. The aim of this study was to evaluate cover crop residue decomposition and nutrient release, and the effects of these plants on soil chemical properties and on onion (Allium cepa L. yield in a no-tillage system. The experiment was carried out in an Inceptisol in southern Brazil, where cover crops were sown in April 2012 and 2013. In July 2013, shoots of weeds (WD, black oats (BO, rye (RY, oilseed radish (RD, oilseed radish + black oats (RD + BO, and oilseed radish + rye (RD + RY were cut at ground level and part of these material from each treatment was placed in litter bags. The litter bags were distributed on the soil surface and were collected at 0, 30, 45, 60, 75, and 90 days after distribution (DAD. The residues in the litter bags were dried, weighed, and ground, and then analyzed to quantify lignin, cellulose, non-structural biomass, total organic carbon (TOC, N, P, K, Ca, and Mg. In November 2012 and 2013, onion crops were harvested to quantify yield, and bulbs were classified according to diameter, and the number of rotted and flowering bulbs was determined. Soil in the 0.00-0.10 m layer was collected for chemical analysis before transplanting and after harvesting onion in December 2012 and 2013. The rye plant residues presented the highest half-life and they released less nutrients until 90 DAD. The great permanence of rye residue was considered a protection to soil surface, the opposite was observed with spontaneous vegetation. The cultivation and addition of dry residue of cover crops increased the onion yield at 2.5 Mg ha-1.

A set cover approach to fast beam orientation optimization in intensity modulated radiation therapy for total marrow irradiation

International Nuclear Information System (INIS)

Lee, Chieh-Hsiu Jason; Aleman, Dionne M; Sharpe, Michael B

2011-01-01

The beam orientation optimization (BOO) problem in intensity modulated radiation therapy (IMRT) treatment planning is a nonlinear problem, and existing methods to obtain solutions to the BOO problem are time consuming due to the complex nature of the objective function and size of the solution space. These issues become even more difficult in total marrow irradiation (TMI), where many more beams must be used to cover a vastly larger treatment area than typical site-specific treatments (e.g., head-and-neck, prostate, etc). These complications result in excessively long computation times to develop IMRT treatment plans for TMI, so we attempt to develop methods that drastically reduce treatment planning time. We transform the BOO problem into the classical set cover problem (SCP) and use existing methods to solve SCP to obtain beam solutions. Although SCP is NP-Hard, our methods obtain beam solutions that result in quality treatments in minutes. We compare our approach to an integer programming solver for the SCP to illustrate the speed advantage of our approach.

A set cover approach to fast beam orientation optimization in intensity modulated radiation therapy for total marrow irradiation

Energy Technology Data Exchange (ETDEWEB)

Lee, Chieh-Hsiu Jason; Aleman, Dionne M [Department of Mechanical and Industrial Engineering, University of Toronto, 5 King' s College Road, Toronto, ON M5S 3G8 (Canada); Sharpe, Michael B, E-mail: chjlee@mie.utoronto.ca, E-mail: aleman@mie.utoronto.ca, E-mail: michael.sharpe@rmp.uhn.on.ca [Princess Margaret Hospital, Department of Radiation Oncology, University of Toronto, 610 University Avenue, Toronto, ON M5G 2M9 (Canada)

2011-09-07

The beam orientation optimization (BOO) problem in intensity modulated radiation therapy (IMRT) treatment planning is a nonlinear problem, and existing methods to obtain solutions to the BOO problem are time consuming due to the complex nature of the objective function and size of the solution space. These issues become even more difficult in total marrow irradiation (TMI), where many more beams must be used to cover a vastly larger treatment area than typical site-specific treatments (e.g., head-and-neck, prostate, etc). These complications result in excessively long computation times to develop IMRT treatment plans for TMI, so we attempt to develop methods that drastically reduce treatment planning time. We transform the BOO problem into the classical set cover problem (SCP) and use existing methods to solve SCP to obtain beam solutions. Although SCP is NP-Hard, our methods obtain beam solutions that result in quality treatments in minutes. We compare our approach to an integer programming solver for the SCP to illustrate the speed advantage of our approach.

The total antioxidant capacity and fluorescence imaging of selected plant leaves commonly consumed in Brunei Darussalam

Science.gov (United States)

Watu, Aswani; Metussin, Nurzaidah; Yasin, Hartini M.; Usman, Anwar

2018-02-01

We investigated the total antioxidant capacity and fluorescence imaging of several selected plants, namely Centella asiatica, Aidia borneensis and Anacardium occidentale, which are grown and traditionally consumed in Brunei Darussalam. The total antioxidant capacities of aqueous-methanolic infusions of their leaves were measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity, and microscopic fluorescence images were measured to identify the fluorescent substances bound in the leaves. We found that the total antioxidant capacity of their infusions is estimated to be 150, 25, 15 folds, respectively, lower compared with that of the standard gallic acid. Accordingly, we demonstrated that the relative antioxidant activity of young and matured leaves agrees with the intensity of red light emission of their fresh leaves upon UV excitation. Thus, this non-invasive spectroscopic method can be potentially utilized to indicate the antioxidants in plant leaves qualitatively.

Ground cover and tree growth on calcareous minesoils: Greater influence of soil surface than nitrogen rate or seed mix

International Nuclear Information System (INIS)

Kost, D.A.; Vimmerstedt, J.P.

1994-01-01

Growth of ground cover and trees was evaluated for five growing seasons on calcareous coal minesoil surfaces (standard graded topsoil, graded and ripped topsoil, graded gray cast overburden) in southeastern Ohio. Soil surface plots were seeded in September 1987 with either a standard herbaceous seed mix [orchardgrass (Dactylis glomerata L.), timothy (Phleum pratense L.), perennial ryegrass (Lolium perenne L.), Kentucky bluegrass (Poa pratensis L.), Ranger alfalfa (Medicago sativa L.), Mammoth red clover (Trifolium pratense L.), Empire birdsfoot trefoil (Lotus corniculatus L.), and wheat (Triticum aestivum L.)], or a modified mix using no alfalfa and half the rate of orchardgrass. Nitrogen (45, 90, or 135 kg ha/N) was applied as ammonium nitrate in September 1987 and April 1989. White ash (Fraxinus americana L.), silver maple (Acer saccharinum L.), northern red oak (Quercus rubra L.), and eastern white pine (Pinus strobus L.) were planted in spring 1989 into 0.8 m-wide strips sprayed with glyphosate herbicide at 2.24 kg/ha in October 1988. Total cover and total biomass were highest in July 1989, following the last application of nitrogen fertilizer in April 1989. Total cover ranged from 44% to 56%, and total biomass ranged from 102 to 162 g/0.5 m 2 from 1990 to 1993. Total cover and total biomass were lower at the lowest nitrogen rate in 1989 only. Type of herbaceous seed mix did not affect growth of ground cover or trees. Overall tree survival was 82.0% the first year but declined to 40.6% after 5 yr. Survival varied significantly among all tree species (3.5% for pine, 22.2% for oak, 38.5% for maple, 98.1% for ash)

Total quality control: the deming management philosophy applied to nuclear power plants

International Nuclear Information System (INIS)

Heising, C.D.; Wetherell, D.L.; Melhem, S.A.; Sato, M.

1987-01-01

In recent years, a call has come for the development of inherently safe nuclear reactor systems that cannot have large-scale accidents. In the search for the perfect inherently safe reactor system, some are calling for the institution of computerized automated control of reactors eliminating most human operators from the control room. A different approach to the problem of the control of inherently safe reactors is that both future and present nuclear power plants need to institute total quality control (TQC) to plant operations and management. The Deming management philosophy of TQC has been implemented in a wide range of industries - particularly in Japan and the US. Specific attention is given, however, to TQC implementation in the electric power industry as applied to nuclear plants. The Kansai Electric Power Company and Florida Power and Light Company have recently implemented TQC. Statistical quality control methods have been applied to monitor and control reactor variables (for example, to the steam generator water level important to start-up operations of pressurized water reactors)

Colored polyethylene soil covers and grafting effects on cucumber flowering and yield

Directory of Open Access Journals (Sweden)

Fonseca Inês Cristina de Batista

2003-01-01

Full Text Available Cucumber (Cucumis sativus L. is one of the most cultivated vegetable crops in plastic greenhouses in Brazil because of the short cycle and its high economic value in off-season harvests. To better understand this management technique the effect of different colored polyethylene soil covers was evaluated in relation to flowering and yield of the hybrid cucumber 'Yoshinari' grafted or not on the hybrid squash 'Ikky'. The polyethylene cover colors were black, white on black and green plus a control without cover. Covered but not grafted crops had a more uniform flowering distribution. The number of flowers was greater for the white/black grafted treatment. All the polyethylene covers favored flowering for the non grafted plants. Grafting reduced flowering for the black or green polyethylene covers treatments. The fruit set increased with the use of polyethylene cover but was not influenced by grafting. The uniform distribution of flowering remained during fruiting only for grafted plants and soil covered with black or green polyethylene. Both polyethylene cover and grafting favored early harvesting. The 'Yoshinari'/'Ikky' graft caused taller plants but fruit were thicker and smaller and did not meet the commercial standard. The best quality fruit and highest yields were obtained in the black and white/black treatments, without grafting.

Enhanced Cover Assessment Project:Soil Manipulation and Revegetation Tests

Energy Technology Data Exchange (ETDEWEB)

Waugh, W. Joseph [Navarro Research and Engineering, Inc.; Albright, Dr. Bill [Desert Research Inst. (DRI), Reno, NV (United States); Benson, Dr. Craig [University of Wisconsin-Madison

2014-02-01

The U.S. Department of Energy Office of Legacy Management is evaluating methods to enhance natural changes that are essentially converting conventional disposal cell covers for uranium mill tailings into water balance covers. Conventional covers rely on a layer of compacted clayey soil to limit exhalation of radon gas and percolation of rainwater. Water balance covers rely on a less compacted soil “sponge” to store rainwater, and on soil evaporation and plant transpiration (evapotranspiration) to remove stored water and thereby limit percolation. Over time, natural soil-forming and ecological processes are changing conventional covers by increasing hydraulic conductivity, loosening compaction, and increasing evapotranspiration. The rock armor on conventional covers creates a favorable habitat for vegetation by slowing soil evaporation, increasing soil water storage, and trapping dust and organic matter, thereby providing the water and nutrients needed for plant germination, survival, and sustainable transpiration. Goals and Objectives Our overall goal is to determine if allowing or enhancing these natural changes could improve cover performance and reduce maintenance costs over the long term. This test pad study focuses on cover soil hydrology and ecology. Companion studies are evaluating effects of natural and enhanced changes in covers on radon attenuation, erosion, and biointrusion. We constructed a test cover at the Grand Junction disposal site to evaluate soil manipulation and revegetation methods. The engineering design, construction, and properties of the test cover match the upper three layers of the nearby disposal cell cover: a 1-foot armoring of rock riprap, a 6-inch bedding layer of coarse sand and gravel, and a 2-foot protection layer of compacted fine soil. The test cover does not have a radon barrier—cover enhancement tests leave the radon barrier intact. We tested furrowing and ripping as means for creating depressions parallel to the slope

Feasibility of winter cover crop production under rainfed conditions

African Journals Online (AJOL)

ACSS

CONDITIONS IN THE EASTERN CAPE PROVINCE OF SOUTH AFRICA. L. MUZANGWA, C. ... planting, resulting in higher weed dry weights at 3 and 6 weeks after planting (WAP). April planted cover crops ...... of micro-arthropods in a sub-tropical forest ecosystem ... American Association of Cereal Chemists, Inc. St. Paul ...

Sustainable covers for uranium mill tailings, USA: alternative design, performance, and renovation - 16369

International Nuclear Information System (INIS)

Waugh, William J.; Benson, Craig H.; Albright, William H.

2009-01-01

The U.S. Department of Energy Office of Legacy Management is investigating alternatives to conventional cover designs for uranium mill tailings. A cover constructed in 2000 near Monticello, Utah, USA, was a redundant design with a conventional low-conductivity composite cover overlain with an alternative cover designed to mimic the natural soil water balance as measured in nearby undisturbed native soils and vegetation. To limit percolation, the alternative cover design relies on a 160-cm layer of sandy clay loam soil overlying a 40- cm sand capillary barrier for water storage, and a planting of native sagebrush steppe vegetation to seasonally release soil water through evapotranspiration (ET). Water balance monitoring within a 3.0-ha drainage lysimeter, embedded in the cover during construction, provided convincing evidence that the cover has performed well over a 9-year period (2000- 2009). The total cumulative percolation, 4.8 mm (approximately 0.5 mm yr -1 ), satisfied a regulatory goal of -1 . Most percolation can be attributed to the very wet winter and spring of 2004-2005, when soil water content exceeded the storage capacity of the cover. Diversity, percent cover, and leaf area of vegetation increased over the monitoring period. Field and laboratory evaluations several years after construction show that soil structural development, changes in soil hydraulic properties, and development of vegetation patterns have not adversely impacted cover performance. A new test facility was constructed in 2008 near Grand Junction, Colorado, USA, to evaluate low-cost methods for renovating or transforming conventional covers into more sustainable ET covers. (authors)

Total mercury, methyl mercury, and carbon in fresh and burned plants and soil in Northwestern Ontario

Energy Technology Data Exchange (ETDEWEB)

Mailman, M. [Department of Zoology, University of Manitoba, Winnipeg, Man. R3T 2N2 (Canada); Freshwater Institute, 501 University Crescent, Winnipeg, Man. R3T 2N6 (Canada)]. E-mail: mailmanma@dfo-mpo.gc.ca; Bodaly, R.A. [Department of Zoology, University of Manitoba, Winnipeg, Man. R3T 2N2 (Canada); Freshwater Institute, 501 University Crescent, Winnipeg, Man. R3T 2N6 (Canada)

2005-11-15

Terrestrial plants and soil contain substantial amounts of organic carbon (C) and mercury. Flooding terrestrial areas stimulates microbial methyl mercury (MeHg) production and fish obtain elevated MeHg concentrations. Our purpose was to determine the loss of C, total mercury (THg), and MeHg from boreal plants and soil after burning to assess the potential of burning before flooding to lower MeHg. Fresh plants contained 4 to 52 ng g{sup -1} dry weight (dw) of THg and 0.1 to 1.3 ng g{sup -1} dw of MeHg. Upland soils contained 162{+-}132 ng g{sup -1} dw of THg and 0.6{+-}0.6 ng g{sup -1} dw of MeHg. Complete burning caused plants to lose 96, 98, 97, and 94% of the mass, C, THg, and MeHg, respectively. Upland soil lost 27, 95, 79, and 82% of the mass, C, THg, and MeHg, respectively. Our results demonstrated that a substantial loss of C, THg, and MeHg was caused by burning. - Burning terrestrial vegetation and soil causes substantial losses of organic carbon, total mercury, and methyl mercury.

Total mercury, methyl mercury, and carbon in fresh and burned plants and soil in Northwestern Ontario

International Nuclear Information System (INIS)

Mailman, M.; Bodaly, R.A.

2005-01-01

Terrestrial plants and soil contain substantial amounts of organic carbon (C) and mercury. Flooding terrestrial areas stimulates microbial methyl mercury (MeHg) production and fish obtain elevated MeHg concentrations. Our purpose was to determine the loss of C, total mercury (THg), and MeHg from boreal plants and soil after burning to assess the potential of burning before flooding to lower MeHg. Fresh plants contained 4 to 52 ng g -1 dry weight (dw) of THg and 0.1 to 1.3 ng g -1 dw of MeHg. Upland soils contained 162±132 ng g -1 dw of THg and 0.6±0.6 ng g -1 dw of MeHg. Complete burning caused plants to lose 96, 98, 97, and 94% of the mass, C, THg, and MeHg, respectively. Upland soil lost 27, 95, 79, and 82% of the mass, C, THg, and MeHg, respectively. Our results demonstrated that a substantial loss of C, THg, and MeHg was caused by burning. - Burning terrestrial vegetation and soil causes substantial losses of organic carbon, total mercury, and methyl mercury

Number of endemic and native plant species in the Galapagos Archipelago in relation to geographical parameters

DEFF Research Database (Denmark)

Willerslev, Eske; Hansen, Anders J.; Nielsen, Kirstine Klitgaard

2002-01-01

By simple and multiple regression analyses we investigate updated species numbers of endemic and native vascular plants and seed plants in the Galapagos Archipelago in relation to geographical parameters. We find that the best models to describe species numbers are regression models with log......-transformed species numbers as dependent and log-transformed modified area (i.e. area not covered with barren lava) as an independent variable. This holds both for total species number, for native species number, for endemic species number and for total number of seed plants as well as number of endemic seed plants...

Coupled Environmental Processes in the Mojave Desert and Implications for ET Covers as Stable Landforms

International Nuclear Information System (INIS)

Shafer, D.; Young, M.; Zitzer, S.; McDonald, E.; Caldwell, T.

2006-01-01

Monolayer evapotranspiration (ET) covers are the baseline method for closure of disposal sites for low-level radioactive waste (LLW), mixed LLW, and transuranic (TRU) waste at the Nevada Test Site (NTS). The regulatory timeline is typically 1,000 years for LLW and 10,000 years for TRU waste. Covers for such waste have different technical considerations than those with shorter timelines because they are subject to environmental change for longer periods of time, and because the environmental processes are often coupled. To evaluate these changes, four analog sites (approximately 30, 1,000 to 2,000, 7,000 to 12,500, and 125,000 years in age) on the NTS were analyzed to address the early post-institutional control period (the youngest site), the 1,000-year compliance period for disposal of LLW, and the 10,000-year period for TRU waste. Tests included soil texture, structure, and morphology; surface soil infiltration and hydraulic conductivity; vegetation and faunal surveys; and literature reviews. Separate measurements were made in plant undercanopy and intercanopy areas. The results showed a progressive increase in silt and clay content of surface soils with age. Changes in soil texture and structure led to a fivefold decline in saturated hydraulic conductivity in intercanopy areas, but no change in undercanopies, which were subject to bioturbation. These changes may have been responsible for the reduction in total plant cover, most dramatically in intercanopy areas, primarily because more precipitation either runs off the site or is held nearer to the surface where plant roots are less common. The results suggest that covers may evolve over longer timeframes to stable landforms that minimize the need for active maintenance

Acetone enhances the direct analysis of total condensed tannins in plant tissues by the butanol-HCl-iron assay

Science.gov (United States)

The butanol-HCl spectrophotometric assay is widely used to quantify extractable and insoluble forms of condensed tannin (CT, syn. proanthocyanidin) in foods, feeds, and foliage of herbaceous and woody plants. However, this method underestimates total CT content when applied directly to plant materia...

Environmental monitoring report for Plantex Plant covering 1979

International Nuclear Information System (INIS)

Alexander, R.E.; Cornelius, V.A.

1980-05-01

The environmental monitoring program at Pantex Plant for 1979 is summarized. Monitoring data for both radioactive and non-radioactive species in the local environment are presented. Although plant activities involve the handling of significant quantities of uranium, plutonium, and tritium, only small releases of uranium (depleted in the isotope 235 U) and tritium occurred which could have affected the local environment. Monitoring data indicate that concentrations of these nuclides in the environment are below established criteria for air and water and therefore do not present a health hazard either to employees or to the public

Environmental monitoring report for Pantex Plant covering 1974

International Nuclear Information System (INIS)

Alexander, R.E.

1975-01-01

During 1974 Pantex Plant conducted a monitoring program to determine the concentration of specific radioactive and non-radioactive species in the local environment. Although the plant activities involved the handling of significant quantities of uranium, plutonium, and tritium, only small releases of uranium (depleted in the isotope 235 U) and tritium have occurred which could affect the local environment. Monitoring data indicate that concentrations of these nuclides in the environment are below established criteria for air and water and therefore do not present a health hazard either to employees or to the public. (U.S.)

Species composition, plant cover and diversity of recently reforested ...

African Journals Online (AJOL)

SERVER

2007-12-17

Dec 17, 2007 ... Deforestation, over-cultivation and rural growth have severely ... over-cultivation, plant populations changed, and biolo- ... Restoring community structure (e.g. species composi-tion ... plant diversity at all spatial scales are the criteria that should ..... taxonomic groups in recovering and restored forests.

Cover gas purification in the German LMFBR-programme

International Nuclear Information System (INIS)

Schillings, K.-L.; Wagner, J.; Stade, K. Ch.

1987-01-01

A specific problem of sodium-cooled reactor plants is the purity of the noble gas argon which is used to protect the liquid alkali metal sodium in its systems in order to avoid or reduce disagreeable reactions between sodium and gaseous compounds like moisture or air and organic products like oil and grease. But as this contact cannot completely be excluded, we have to recycle such soiled cover gas. Simultaneously this procedure has to correct the release of radioactivity. Therefore the cover gas purification of primary systems of reactor plants contains the removal of the inorganic chemical disposal and of the nuclear waste. (author)

Polysaccharides, total flavonoids content and antioxidant activities in different parts of Silybum marianum L. plants

Science.gov (United States)

Sun, Jing; Li, Xinhua; Yu, Xiaolei

2017-01-01

Silybum marianum L. is used for the production of silymarin, a flavonoid utilized for regenerating damaged hepatic tissues. Herein, the total flavonoid content (TFC) and polysaccharides content (PC) in the roots, main stems, leaves, fruit receptacles, and pappi of Silybum marianum were determined. The antioxidant activities of plant ethanol extracts were assessed to validate the medicinal potential of the various plant parts. The pappi exhibited the highest TFC (17.10 mg rutin/g of dry plant material), followed by the fruit receptacles (15.34 mg/g). The PC varied from 3.57±0.23 to 11.02±0.35 mg glucose /g dry plant material; the highest PC was obtained from the roots. At 50 ug/mL, the pappi ethanol extract showed the highest 1, 1-Diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging activity (69.68%), followed by the roots (66.02%).

Changes of plant cover of the raised peat-bog Baligówka under the influence of human activity

Directory of Open Access Journals (Sweden)

Malec Magdalena

2016-12-01

Full Text Available The main purpose of the work was to determine the scope and degree of the influence of exploitation on changes of plant cover of the raised peat-bog Baligówka, located in the Orawsko- Nowotarska Valley. The analysis was carried out based on 47 phytosociological surveys using the Braun-Blanquet method. Results of investigations allow to state that excessive drying and fires that took place on the examined object caused wastage of many precious species of plants, especially from the Oxycocco- Sphagnetea class. Their place occupied species belonging to other classes, such as Nardo-Callunetea and Molinio-Arrhenatheretea. The basic cause of drying of the peat-bog and, in consequence, dying of peat formation species is intensified exploitation and connected with this drainage, carried out in the half of the 20th century. Unfortunately, local people up to now illegally have harvested the peat on the investigated object. Decrease in groundwater level leads to accelerated decay of peat, changes in physical and chemical properties of a substratum and, in consequence, changes in trophic values of habitat, what causes great changes in species composition of plant communities.

Summary of decontamination cover manufacturing experience

International Nuclear Information System (INIS)

Ulrich, G.B.; Berry, H.W.

1995-02-01

Decontamination cover forming cracks and vent cup assembly leaks through the decontamination covers were early manufacturing problems. The decontamination cover total manufacturing process yield was as low as 55%. Applicable tooling and procedures were examined. All manufacturing steps from foil fabrication to final assembly leak testing were considered as possible causes or contributing factors to these problems. The following principal changes were made to correct these problems: (1) the foil annealing temperature was reduced from 1375 degrees to 1250 degrees C, (2) the decontamination cover fabrication procedure (including visual inspection for surface imperfections and elimination of superfluous operations) was improved, (3) the postforming dye penetrant inspection procedure was revised for increased sensitivity, (4) a postforming (prewelding) 1250 degrees C/1 h vacuum stress-relief operation was added, (5) a poststress relief (prewelding) decontamination cover piece-part leak test was implemented, (6) the hold-down fixture used during the decontamination cover-to-cup weld was modified, and concomitantly, and (7) the foil fabrication process was changed from the extruding and rolling of 63-mm-diam vacuum arc-remelted ingots (extrusion process) to the rolling of 19-mm-square arc-melted drop castings (drop cast process). Since these changes were incorporated, the decontamination cover total manufacturing process yield has been 91 %. Most importantly, more than 99% of the decontamination covers welded onto vent cup assemblies were acceptable. The drastic yield improvement is attributed primarily to the change in the foil annealing temperature from 1375 degrees to 1250 degrees C and secondarily to the improvements in the decontamination cover fabrication procedure

Sediment balance in four small catechumen's with different land cover in the Central Pyrenes (Spain)

International Nuclear Information System (INIS)

Nadal Romero, E.; Lana-Renault, N.; Serrano-Muela, P.; Reguez, D.; Alvera, B.; Latron, J.; Marti-Bono, C.; Garcia-Ruiz, J. M.

2009-01-01

Four experimental catchment s in the Central Pyrenes were monitored by the Department of Geo-environmental Processes and global Change (Pyrenean Institute of Ecology, CSIC) to assess the hydrological and geomprophological consequences of various land uses and vegetation cover. The catchments were selected along an attitudinal and land-use gradient and included: (i) a sub-Mediterranean environment affected by intense weathering and erosion processes on marls, (ii) an old abandoned cultivated area undergoing vegetation regrowth, (iii) a barely-disturbed forest area, and (iv) a sub-alpine grassland in the high mountains, affected by snow accumulation and melting processes. The results demonstrate that plant cover is a key factor influencing the suspended sediment concentration, total sediment yield and proportion of different types of sediment. (Author) 7 refs.

Establishment and function of cover crops interseeded into corn

Science.gov (United States)

Cover crops can provide ecological services and improve the resiliency of annual cropping systems; however, cover crop use is low in corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] rotations in the upper Midwest due to challenges with establishment. Our objective was to compare three planting me...

Environmental monitoring report for Pantex Plant covering 1980

International Nuclear Information System (INIS)

Alexander, R.E.; Laseter, W.A.

1981-03-01

This report summarizes the environmental monitoring program at Pantex Plant for 1980. Monitoring data for both radioactive and non-radioactive species in the local environment is presented. Although plant activities involve the handling of significant quantities of uranium, plutonium, and tritium, only small releases of uranium (depleted in the isotope 235 U) and tritium occurred which could have affected the local environment. Monitoring data indicate that concentrations of these nuclides in the environment are below established criteria for air and water and therefore do not present a health hazard either to employees or to the public

Environmental monitoring report for Pantex Plant covering 1982

International Nuclear Information System (INIS)

Laseter, W.A.

1983-03-01

This report summarizes the environmental monitoring program at Pantex Plant for 1982. Monitoring data for both radioactive and non-radioactive species in the local environment is presented. Plant activities involve the handling of significant quantities of uranium, plutonium, and tritium. However, only small releases of uranium (depleted in the isotope 235 U) and tritium occurred which could have affected the local environment. Monitoring data indicate that concentrations of these nuclides in the environment are below established criteria for air and water and therefore should not present a health hazard either to employees or to the public

Total Phenolic, Flavonoid, Tomatine, and Tomatidine Contents and Antioxidant and Antimicrobial Activities of Extracts of Tomato Plant

Science.gov (United States)

Silva-Beltrán, Norma Patricia; Ruiz-Cruz, Saul; Cira-Chávez, Luis Alberto; Estrada-Alvarado, María Isabel; Ornelas-Paz, José de Jesús; López-Mata, Marco Antonio; Del-Toro-Sánchez, Carmen Lizette; Ayala-Zavala, J. Fernando; Márquez-Ríos, Enrique

2015-01-01

The purpose of this study was to evaluate the antioxidant and antimicrobial properties of extracts of different fractions of two tomato plant cultivars. The stems, roots, leaves, and whole-plant fractions were evaluated. Tomatine and tomatidine were identified by HPLC-DAD. The leaf extracts from the two varieties showed the highest flavonoids, chlorophyll, carotenoids, and total phenolics contents and the highest antioxidant activity determined by DPPH, ABTS, and ORAC. A positive correlation was observed between the antioxidant capacities of the extracts and the total phenolic, flavonoid, and chlorophyll contents. The Pitenza variety extracts inhibited the growth of pathogens such as E. coli O157:H7, Salmonella Typhimurium, Staphylococcus aureus, and Listeria ivanovii, yielding inhibition halos of 8.0 to 12.9 mm in diameter and MIC values of 12.5 to 3.125 mg/mL. These results suggest that tomato plant shows well potential as sources of various bioactive compounds, antioxidants, and antimicrobials. PMID:26609308

Total data management in the La Hague reprocessing plant

International Nuclear Information System (INIS)

Berthion, Y.; Perot, J.P.; Silie, P.

1993-01-01

Due to the complexity of a spent fuel reprocessing plant and its nuclear characteristics, the operators must have real-time access to updated information on many subjects. To meet these requirements effectively, Cogema has installed a number of diversified data processing systems linked by a communications network called Haguenet. The whole system forms the La Hague Total Data Management System (TDMS) which performs a full range of functions, namely production data management, maintenance data management, technical documentation and miscellaneous. Some examples of the main process data management applications implemented within the La Hague TDMS are briefly described (nuclear materials and waste follow-up, analytical data management, operating procedures management and site inspection management). Also presented are some examples of the maintenance-related systems implemented within the La Hague TDMS (diagnostic assistance system, software maintenance center, maintenance interventions demand and spare parts data management). (Z.S.)

Comparative research of international exchange of plant products

Directory of Open Access Journals (Sweden)

Đorović Milutin T.

2003-01-01

Full Text Available The well known events which had taken place in our country over the period 1989-2001 provoked adverse effects on foreign trade exchange of the total economy, agriculture and commodities of plant origin. These effects and changes were analyzed using corresponding indices for the sub periods 1989-1992 and 1998-2001. The foreign trade exchange balance was substantially negative in both sub periods over the analyzed period showing an aggravating trend. Export covering import declined from 78.09% to only 47.71%. The positive balance of exchange of agricultural, especially commodities of plant origin in the first four years was turned into a negative balance of exchange in the second four years. Export covering import at the agricultural level declined from 164.79% to 78.58% and at the level of commodities of plant origin from 201,76% to 87.35%. There was a significant disturbance of commodity and regional structure exchange. The share of agriculture in the total export of the country was raised from 13.82% to 18.16%. The share of plant originating commodities in the total export of agriculture was raised from 71,96% to 86,34%. Basic agricultural products predominated in the export. In addition, in the domestic export the share of developed countries decreased which contributed to poor export results and increased the import dependence of the country. Considering the above said, the need arises to increase substantially agricultural production, i.e. commodities of plant origin. The structure and output of these productions should meet the needs of both domestic and foreign markets. International standards need to be applied in order to take hold of new foreign markets, exporting high technology processed products, using intensive and efficient promotive activities. Subsequently, greater investments and a planned production are needed, liberalization and especially the system of import control in foreign trade exchange of agricultural products, i

Nuclear power plants 1995 - a world survey

International Nuclear Information System (INIS)

Anon.

1996-01-01

The atw Statistics Report compiled by atw lists 428 nuclear power plants with 363 397 gross MWe in operation in 30 countries in late 1995. Another 62 units with 55 180 gross MWe were under construction in 18 countries. This adds up to a total of 490 units with an aggregate 418 577 MWe. In the course of 1995 four units in four countries started commercial operation. In the survey of electricity generation in 1995 for which no information was made available from China and Kasachstan, a total of 417 nuclear power plants were covered. In the year under review they generated an aggregate 2 282 614 GWH, which is 3.4% more than in the previous year. The highest nuclear generation again was recorded in the USA with 705 771 GWh, followed by France with 377 021 GWh. The Grohnde power station in Germany attained the maximum annual production figure of 11 359 GWh. The survey includes nine tables indicating the generating performance of each nuclear power plant, the development of electricity generation in nuclear plants, and status of nuclear power plants at the end of 1995 arranged by countries, types of reactors, and reactor manufacturers. (orig.) [de

C and N accumulations in soil aggregates determine nitrous oxide emissions from cover crop treated rice paddy soils during fallow season

International Nuclear Information System (INIS)

Pramanik, Prabhat; Haque, Md. Mozammel; Kim, Sang Yoon; Kim, Pil Joo

2014-01-01

Combination of leguminous and non-leguminous plant residues are preferably applied in rice paddy soils to increase the rate of organic matter mineralization and to improve plant growth. However, organic matter addition facilitates methane (CH 4 ) emission from rice paddy soil. Mineralization of organic nitrogen (N) increases NO 3 –N concentrations in soil, which are precursors for the formation of nitrous oxide (N 2 O). However, N 2 O is a minor greenhouse gas emitted from submerged rice field and hence is not often considered during calculation of total global warming potential (GWP) during rice cultivation. The hypothesis of this study was that fluxes of N 2 O emissions might be changed after removal of flooded water from rice field and the effect of cover crops on N 2 O emissions in the fallow season might be interesting. However, the effects of N-rich plant residues on N 2 O emission rates in the fallow season and its effect on annual GWP were not studied before. In this experiment, combination of barley (non-leguminous) and hairy vetch (leguminous) biomasses were applied at 9 Mg ha −1 and 27 Mg ha −1 rates in rice paddy soil. Cover crop application significantly increased CH 4 emission flux while decreased N 2 O emissions during rice cultivation. The lowest N 2 O emission was observed in 27 Mg ha −1 cover crop treated plots. Cover crop applications increased N contents in soil aggregates especially in smaller aggregates (< 250 μm), and that proportionately increased the N 2 O emission potentials of these soil aggregates. Fluxes of N 2 O emissions in the fallow season were influenced by the N 2 O emission potentials of soil aggregates and followed opposite trends as those observed during rice cultivation. Therefore, it could be concluded that the doses of cover crop applications for rice cultivation should not be optimized considering only CH 4 , but N 2 O should also be considered especially for fallow season to calculate total GWP. - Highlights: �

Chemical behaviour of zinc in cover gas environments

International Nuclear Information System (INIS)

Thorley, A.W; Blundell, A.; Lloyd, R.

1987-01-01

The possibility that enhancement of 65-Zn in the cover gas regions of reactor plant may increase levels of radioactivity and provide potential embrittlement situations has lead to a limited metallurgical and chemical investigation into how this element behaves in cover gas environments. This paper reports the chemical findings from those investigations and compare results obtained with those anticipated from thermodynamic predictions

Burn Severity Dominates Understory Plant Community Response to Fire in Xeric Jack Pine Forests

Directory of Open Access Journals (Sweden)

Bradley D. Pinno

2016-04-01

Full Text Available Fire is the most common disturbance in northern boreal forests, and large fires are often associated with highly variable burn severities across the burnt area. We studied the understory plant community response to a range of burn severities and pre-fire stand age four growing seasons after the 2011 Richardson Fire in xeric jack pine forests of northern Alberta, Canada. Burn severity had the greatest impact on post-fire plant communities, while pre-fire stand age did not have a significant impact. Total plant species richness and cover decreased with disturbance severity, such that the greatest richness was in low severity burns (average 28 species per 1-m2 quadrat and plant cover was lowest in the high severity burns (average 16%. However, the response of individual plant groups differed. Lichens and bryophytes were most common in low severity burns and were effectively eliminated from the regenerating plant community at higher burn severities. In contrast, graminoid cover and richness were positively related to burn severity, while forbs did not respond significantly to burn severity, but were impacted by changes in soil chemistry with increased cover at pH >4.9. Our results indicate the importance of non-vascular plants to the overall plant community in this harsh environment and that the plant community is environmentally limited rather than recruitment or competition limited, as is often the case in more mesic forest types. If fire frequency and severity increase as predicted, we may see a shift in plant communities from stress-tolerant species, such as lichens and ericaceous shrubs, to more colonizing species, such as certain graminoids.

SOIL CHEMICAL ATTRIBUTES AND LEAF NUTRIENTS OF ‘PACOVAN’ BANANA UNDER TWO COVER CROPS

Directory of Open Access Journals (Sweden)

JOSÉ EGÍDIO FLORI

2016-01-01

Full Text Available Banana is one of the most consumed fruits in the world, which is grown in most tropical countries. The objective of this work was to evaluate the main attributes of soil fertility in a banana crop under two cover crops and two root development locations. The work was conducted in Curaçá, BA, Brazil, between October 2011 and May 2013, using a randomized block design in split plot with five repetitions. Two cover crops were assessed in the plots, the cover 1 consisting of Pueraria phaseoloides, and the cover 2 consisting of a crop mix with Sorghum bicolor, Ricinus communis L., Canavalia ensiformis, Mucuna aterrima and Zea mays, and two soil sampling locations in the subplots, between plants in the banana rows (location 1 and between the banana rows (location 2. There were significant and independent effects for the cover crop and sampling location factors for the variables organic matter, Ca and P, and significant effects for the interaction between cover crops and sampling locations for the variables potassium, magnesium and total exchangeable bases. The cover crop mix and the between-row location presented the highest organic matter content. Potassium was the nutrient with the highest negative variation from the initial content and its leaf content was below the reference value, however not reducing the crop yield. The banana crop associated with crop cover using the crop mix provided greater availability of nutrients in the soil compared to the coverage with tropical kudzu.

Benefits from cover crops based on plant-microbial interaction

OpenAIRE

Manici , L.M.; Kelderer, M.; Caputo, F.; De Luca Picione , F.; Topp, A.

2014-01-01

This study was performed on the impact of two different cover crops (cereal and legume) on composition of root fungal endophytes and rhizospheric bacterial communities as a function of crop health in replanted apple orchards.

Winter cover crops as a best management practice for reducing nitrogen leaching

Science.gov (United States)

Ritter, W. F.; Scarborough, R. W.; Chirnside, A. E. M.

1998-10-01

The role of rye as a winter cover crop to reduce nitrate leaching was investigated over a three-year period on a loamy sand soil. A cover crop was planted after corn in the early fall and killed in late March or early April the following spring. No-tillage and conventional tillage systems were compared on large plots with irrigated corn. A replicated randomized block design experiment was conducted on small plots to evaluate a rye cover crop under no-tillage and conventional tillage and with commercial fertilizer, poultry manure and composted poultry manure as nitrogen fertilizer sources. Nitrogen uptake by the cover crop along with nitrate concentrations in groundwater and the soil profile (0-150 cm) were measured on the large plots. Soil nitrate concentrations and nitrogen uptake by the cover crop were measured on the small plots. There was no significant difference in nitrate concentrations in the groundwater or soil profile with and without a cover crop in either no-tillage or conventional tillage. Annual amounts of nitrate-N leached to the water-table varied from 136.0 to 190.1 kg/ha in 1989 and from 82.4 to 116.2 kg/ha in 1991. Nitrate leaching rates were somewhat lower with a cover crop in 1989, but not in 1990. There was no statistically significant difference in corn grain yields between the cover crop and non-cover crop treatments. The planting date and adequate rainfall are very important in maximizing nitrogen uptake in the fall with a rye cover crop. On the Delmarva Peninsula, the cover crop should probably be planted by October 1 to maximize nitrogen uptake rates in the fall. On loamy sand soils, rye winter cover crops cannot be counted on as a best management practice for reducing nitrate leaching in the Mid-Atlantic states.

Allelopathic effects of two cover crops Commelina diffusa Burm. F. and Tradescantia zebrina Shunltz on Coffea arabica L.

Directory of Open Access Journals (Sweden)

Georgina Berroa Navarro

2016-03-01

Full Text Available Allelopathic effect of the cover crops Tradescantia zebrina Shunltz (cucaracha and Commelina diffusa Burm. F. (canutillo were evaluated on Coffea arabica Lin. seeds Caturra Rojo variety. Germination tests were carried out “in vitro” and it was evaluated the root longitude, percentage of total germination and period of germination, as well as the height of the plant and the emergency percentage for the incorporation tests to the soil. It was also carried out, to both over crops, the preliminary chemical qualitative characterization. The results showed that the extracts of T. zebrina and of C. diffusa stimulated the “in vitro” germination and growth of C. arabica at different concentration levels. The incorporation to the soil of the extracts of C. diffusa stimulated the development of the plants of C. arabica, in a significant way, that supposes a considerable advantage in that concerns to the employment of these cover crops, when not implying noxious effects beside all the benefits implied when using cover crops. These last ones go from the protection and improvement of the properties of the soil, to the control of the spontaneous flora in the coffee agroecosystems.

Los Angeles 1-Million tree canopy cover assessment

Science.gov (United States)

Gregory E. McPherson; James R. Simpson; Qingfu Xiao; Wu Chunxia

2008-01-01

The Million Trees LA initiative intends to chart a course for sustainable growth through planting and stewardship of trees. The purpose of this study was to measure Los Angeles's existing tree canopy cover (TCC), determine if space exists for 1 million additional trees, and estimate future benefits from the planting. High resolution QuickBird remote sensing data,...

Total phenol content and antioxidant activity of water solutions of plant extracts

Directory of Open Access Journals (Sweden)

Mirela Kopjar

2009-01-01

Full Text Available Water solutions of extracts were investigated for total phenol content, flavonoid content and antioxidant activity. Susceptibility to degradation of water solutions of plant extracts, under light and in the dark, during storage at room temperature was investigated in order to determine their stability prior to their application for fortification of food products. Large dispersion of total phenol (TP content in the investigated model solutions of selected extracts (olive leaves, green tea, red grape, red wine, pine bark PE 5:1, pine bark PE 95 %, resveratrol, ranging from 11.10 mg GAE/100 mL to 92.19 mg GAE/100 mL was observed. Consequently, large dispersion of total flavonoids (TF content (8.89 mg to 61.75 mg CTE/100 mL was also observed. Since phenols have been mostly responsible for antioxidant activity of extracts, in most cases, antioxidant activity followed the TP content. That was proven by estimation of correlation coefficient between the total phenol content and antioxidant activity. Correlation coefficients between investigated parameters ranged from 0.5749 to 0.9604. During storage of 5 weeks at room temperature loss of phenols and flavonoids occurred. Antioxidant activity decreased with the decrease of TP and TF content. Degradations of phenols and flavonoids were more pronounced in samples stored at light.

Site quality influence over understory plant diversity in old-growth and harvested Nothofagus pumilio forests

Directory of Open Access Journals (Sweden)

E. A. Gallo

2013-04-01

Full Text Available Aim of study: The effects and interactions of shelterwood forest harvesting and site qualities over understory plant species diversity and composition were compared among primary and harvested Nothofagus pumilio forests.Area of study: Tierra del Fuego (Argentina, on three pure conditions (one and six year-old harvested, and primary without previous harvesting forests and three site qualities (high, medium and low.Material and Methods: Understory richness and cover (% were registered in five replicates of 1 hectare each per treatment. Taxonomic species were classified in categories (groups, origin and life forms. Two-way ANOVAs and multivariate analyses were conducted.Main results: Shelterwood harvesting and site quality significantly influenced understory cover and richness, which allow the introduction of native and exotic species and increasing of dicot and monocot covers. In dicots, monocots, exotics and total groups, higher richness and covers were related to time. Meanwhile, cover reached similar high values in all site qualities on dicot, native and total groups. On the other hand, monocot and exotic richness and cover remain similar in primary and recently harvested forests, and greatly increased in old harvested forests. Mosses and ferns were among the most sensitive groups.Research highlights: Impacts of shelterwood cut depend on site quality of the stands and time since harvesting occurs. For this, different site quality stands should received differential attention in the development of conservation strategies, as well as variations in the shelterwood implementation (as irregularity and patchiness should be considered to better promote understory plant species conservation inside managed areas.Key words: plant species conservation; years after harvesting; forest management; Tierra del Fuego.

Cover gas purification experience at KNK

Energy Technology Data Exchange (ETDEWEB)

Richard, H; Stade, K Ch [Kernkraftwerk-Betriebsgesellschaft m.b.H., Eggenstein-Leopoldshafen (Germany); Stamm, H H [Institute of Radiochemistry, Nuclear Research Center, Karsruhe (Germany)

1987-07-01

KNK II is an experimental, sodium cooled fast breeder reactor. The reactor was operated until 1974 with a thermal core (KNK I). The plant was converted into a fast breeder reactor (KNK II) from 1974 to 1977. The commissioning of KNK II was started in October 1977 with the first fast core KNK 11/1. After 400 effective full power days (EFPD) the reactor was shut down in August 1982. After replacing the complete core by the second fast core KNK 11/2, the plant went into operation again in August 1983. In August 1986 nearly 400 EFPD were achieved with the second fast core. Argon is used as cover gas in the primary and secondary sodium systems of KNK. In former times fresh argon was supplied by a bundle of gas cylinders. Later on a liquid argon supply was installed. Purification of cover gas is done by flushing only. During KNK I operation no fuel failures occurred. The primary cover gas activity was characterized by the formation of Ar-41, only small quantities of fission gas were measured, released from 'tramp uranium'. Therefore, no problems existed during KNK I operation with regard to radioactive gas disposal. However, after start-up of KNK II, several fuel elements failed. Until August 1986, five fuel failures were observed, two in KNK 11/1, and three in KNK 11/2. Sometimes, operation with defective fuel pins caused problems when fission gases leaked into the containment atmosphere, and the access had to be restricted. The purging rate of the primary cover gas was limited by the capacity of the charcoal filters in the delay line. Of all non-radioactive impurities, hydrogen (H{sub z}) and nitrogen (N{sub 2}) were of most importance in the primary cover gas. Main source of both impurities was the ingress of air and atmospheric moisture during handling operations in shutdown periods. An other possible source for hydrogen might be a release from the steel-clad zirconium hydride, used as moderator in the moderated driver fuel elements. Additional nitrogen may diffuse

Cherry tomato yield in greenhouses with different plastic covers

Directory of Open Access Journals (Sweden)

Ester Holcman

2017-08-01

Full Text Available ABSTRACT: The objective of the present study was to evaluate the influence of different plastic covers on microclimate and cherry tomato yield in greenhouses. The experiments were carried out in Piracicaba, state of São Paulo (Brazil, during three growing periods (2008/2009/2010. A greenhouse was divided in: Environment I (EI - covered with plastic film anti-UV and thermo-reflective shading screen, and Environment II (EII - covered with diffusive plastic film; monitored with automatic weather sensors; and cultivated with cherry tomato (‘Sweet Grape’ and ‘Sweet Million’. Use of diffusive plastic in greenhouses provides a better inside distribution of solar energy without causing major changes in air temperature and relative humidity, resulting in higher yield (kg plant-1, fruits quantity (number plant-1 and fruits average weight than those obtained under thermo-reflective shading screen.

Agro-environmental scheme for segetal plant conservation in Wallonia (Belgium: an assessment in conventional and organic fields

Directory of Open Access Journals (Sweden)

Lemoine, C.

2018-01-01

Full Text Available Description of the subject. Segetal plant species are highly threatened in arable land. They are an integral part of agricultural history and biodiversity in Western Europe. In Wallonia (southern Belgium, an agro-environmental scheme (AES has been adopted for their conservation. It consists of strips on a field margin, with at least 60% cereals in crop rotation, and proscribes spraying and fertilisation. Objectives. This paper assessed the impact of an AES on segetal species conservation. Method. In eight organic fields and six conventional fields, a vegetation survey was performed on an AES strip and on a control margin of each field. Evenness, richness, cover and species composition for both total and segetal species were compared between AES strips and their corresponding control margins. Also, a cover of pernicious weeds was considered to be a factor in the rejection of AES by farmers. Results. In conventional agriculture, species richness (total and segetal and cover (total and segetal were higher in the AES than in the respective control; however, pernicious weed cover was also enhanced. In organic fields, total species richness was higher and pernicious weed cover was lower in the AES than in the respective control. Total evenness was higher in organic than in conventional fields, due to the co-dominance of several species. Under the AES, species composition and abundance remained different between conventional and organic fields. In all cases, rare species were hardly found in our survey. Conclusions. AES promote plant diversity in both organic and conventional fields. Sowing AES strips with uncleaned seeds from well-preserved fields, or species introduction, are recommended to enhance rare species recovery.

Environmental monitoring report for Pantex Plant covering 1984

International Nuclear Information System (INIS)

Laseter, W.A.

1985-01-01

This report summarizes the environmental monitoring program at Pantex Plant for 1984. It has been prepared in accordance with the United States Department of Energy Order 5484.1. This report presents monitoring data for both radioactive and non-radioactive species in the local environment. Plant activities involve the handling of significant quantities of uranium, plutonium, and tritium. However, only a small release of tritium occurred which could have affected the local environment. Monitoring data indicate that concentrations of this nuclide in the environment are below established criteria for air and water and therefore should not present a health hazard either to employees or to the public. 22 refs., 7 figs., 23 tabs

Environmental monitoring report for Pantex Plant covering 1978

International Nuclear Information System (INIS)

Alexander, R.E.; Cornelius, V.A.

1979-05-01

This report summarizes the environmental monitoring program at Pantex Plant for 1978. It has been prepared in accordance with the United States Department of Energy Manual Chapter 0513. This report presents monitoring data for both radioactive and non-radioactive species in the local environment. Although plant activities involve the handling of significant quantities of uranium, plutonium, and tritium, only small releases of uranium (depleted in the isotope 235 U) and tritium occurred which could have affected the local environment. Monitoring data indicate that concentrations of these nuclides in the environment are below established criteria for air and water and therefore should not present a health hazard either to employees or to the public

FP 6 EU - COVERS. Coordination action - VVER safety research

International Nuclear Information System (INIS)

Vasa, I.

2008-01-01

In this work research program of the European Union FP 6 - COVERS coordinated by the NRI Rez is presented. COVERS is designed to improve professional and communication environment in the specific area covering all aspects of safe and reliable operation of nuclear power plants with VVER-440 and VVER-1000 reactors. Project Consortium is composed of 26 research and development, engineering and technical support organisations of European VVER-operating and other EU and non-EU countries.

Topics to be covered in safety analysis reports for nuclear power plants with pressurized water reactors or boiling water reactors in the F.R.G

International Nuclear Information System (INIS)

Kohler, H.A.G.

1977-01-01

This manual aims at defining the standards to be used in Safety Analysis Reports for Nuclear Power Plants with Pressurized Water Reactors or Boiling Water Reactors in the Federal Republic of Germany. The topics to be covered are: Information about the site (geographic situation, settlement, industrial and military facilities, transport and communications, meteorological conditions, geological, hydrological and seismic conditions, radiological background), description of the power plant (building structures, safety vessel, reactor core, cooling system, ventilation systems, steam power plant, electrical facilities, systems for measurement and control), indication of operation (commissioning, operation, safety measures, radiation monitoring, organization), incident analysis (reactivity incidents, loss-of-coolant incidents, external impacts). (HP) [de

Litter Accumulation and Nutrient Content of Roadside Plant Communities in Sichuan Basin, China.

Science.gov (United States)

He, Huiqin; Monaco, Thomas

2017-08-30

It is widely recognized that feedbacks exist between plant litter and plant community species composition, but this relationship is difficult to interpret over heterogeneous conditions typical of modified environments such as roadways. Given the need to expedite natural recovery of disturbed areas through restoration interventions, we characterized litter accumulation and nutrient content (i.e., organic carbon, total N, and P) and quantified their association with key plant species. Plant species cover and litter characteristics were sampled at 18 successional forest plant communities along major roadways in Sichuan Basin, western China. Variation in litter across communities was assessed with principal component analysis (PCA) and species with the highest correlation to PCA axes were determined with Pearson's r coefficients. Plant communities with the longest time since road construction (i.e., 70 years) were distinctly different in litter total N and organic carbon compared to plant communities with a shorter disturbance history. We encountered 59 plant species across sampling plots, but only four rare species (i.e., frequency plant litter across heavily disturbed landscapes and how litter characteristics and rare plant species are correlated.

Remote sensing to monitor cover crop adoption in southeastern Pennsylvania

Science.gov (United States)

In the Chesapeake Bay watershed, winter cereal cover crops are often planted in rotation with summer crops to reduce the loss of nutrients and sediment from agricultural systems. Cover crops can also improve soil health, control weeds and pests, supplement forage needs, and support resilient croppin...

Short-Term Power Plant GHG Emissions Forecasting Model

International Nuclear Information System (INIS)

Vidovic, D.

2016-01-01

In 2010, the share of greenhouse gas (GHG) emissions from power generation in the total emissions at the global level was about 25 percent. From January 1st, 2013 Croatian facilities have been involved in the European Union Emissions Trading System (EU ETS). The share of the ETS sector in total GHG emissions in Croatia in 2012 was about 30 percent, where power plants and heat generation facilities contributed to almost 50 percent. Since 2013 power plants are obliged to purchase all emission allowances. The paper describes the short-term climate forecasting model of greenhouse gas emissions from power plants while covering the daily load diagram of the system. Forecasting is done on an hourly domain typically for one day, it is possible and more days ahead. Forecasting GHG emissions in this way would enable power plant operators to purchase additional or sell surplus allowances on the market at the time. Example that describes the operation of the above mentioned forecasting model is given at the end of the paper.(author).

Design and Installation of a Disposal Cell Cover Field Test

Energy Technology Data Exchange (ETDEWEB)

Benson, C.H. [University of Wisconsin–Madison, Madison, Wisconsin; Waugh, W.J. [S.M. Stoller Corporation, Grand Junction, Colorado; Albright, W.H. [Desert Research Institute, Reno, Nevada; Smith, G.M. [Geo-Smith Engineering, Grand Junction, Colorado; Bush, R.P. [U.S. Department of Energy, Grand Junction, Colorado

2011-02-27

The U.S. Department of Energy’s Office of Legacy Management (LM) initiated a cover assessment project in September 2007 to evaluate an inexpensive approach to enhancing the hydrological performance of final covers for disposal cells. The objective is to accelerate and enhance natural processes that are transforming existing conventional covers, which rely on low-conductivity earthen barriers, into water balance covers, that store water in soil and release it as soil evaporation and plant transpiration. A low conductivity cover could be modified by deliberately blending the upper layers of the cover profile and planting native shrubs. A test facility was constructed at the Grand Junction, Colorado, Disposal Site to evaluate the proposed methodology. The test cover was constructed in two identical sections, each including a large drainage lysimeter. The test cover was constructed with the same design and using the same materials as the existing disposal cell in order to allow for a direct comparison of performance. One test section will be renovated using the proposed method; the other is a control. LM is using the lysimeters to evaluate the effectiveness of the renovation treatment by monitoring hydrologic conditions within the cover profile as well as all water entering and leaving the system. This paper describes the historical experience of final covers employing earthen barrier layers, the design and operation of the lysimeter test facility, testing conducted to characterize the as-built engineering and edaphic properties of the lysimeter soils, the calibration of instruments installed at the test facility, and monitoring data collected since the lysimeters were constructed.

New CHP plant for a rubber products manufacturer

International Nuclear Information System (INIS)

Vila, R.; Martí, C.

2016-01-01

At the end of 2014 the company Industrias de Hule Galgo decided to undertake the installation project of an efficient CHP plant for its production plant, with the aim of bringing down energy costs and improving the company’s competitive position in the market. The new plant has already started its first operational phase. The project has comprised the installation of a single cycle with gas-powered gensets providing a total electrical capacity of 6.6 MW. This provides the necessary thermal oil for the production plant; covers 100% of the electrical power consumed by the industrial complex; and also generates cooling water, giving improved production capacity by supercooling the extrusion system. To execute these works, Industrias de Hule Galgo contracted the services of engineering company AESA to provide the engineering, procurement and construction of the CHP plant. (Author)

Guidelines for selection of radiological protective head covering

International Nuclear Information System (INIS)

Galloway, G.R. Jr.

1995-08-01

The hood is recognized throughout the nuclear industry as the standard radiological protective head covering for use in radioactively contaminated work environments. As of June 15, 1995, hoods were required for all activities performed in contaminated areas at the Y-12 Plant. The use of hoods had historically been limited to those radiological activities with a high potential for personnel contamination. Due to the large size of many posted contaminated areas at the Y-12 Plant, and compounding safety factors, requirements for the use of hoods are being reevaluated. The purpose of the evaluation is to develop technically sound guidelines for the selection of hoods when prescribing radiological protective head covering. This report presents the guidelines for selection of radiological protective hoods

Monitoring the performance of an alternative cover using caisson lysimeters

Energy Technology Data Exchange (ETDEWEB)

Waugh, W.J.; Smith, G.M.; Mushovic, P.S.

2004-02-29

The U.S. Department of Energy (DOE) office in Grand Junction, Colorado, and the U.S. Environmental Protection Agency (EPA), Region 8, collaborated on a series of field lysimeter studies to design and monitor the performance of an alternative cover for a uranium mill tailings disposal cell at the Monticello, Utah, Superfund Site. Because groundwater recharge is naturally limited at Monticello in areas with thick loess soils, DOE and EPA chose to design a cover for Monticello using local soils and a native plant community to mimic this natural soilwater balance. Two large drainage lysimeters fabricated of corrugated steel culvert lined with high-density polyethylene were installed to evaluate the hydrological and ecological performance of an alternative cover design constructed in 2000 on the disposal cell. Unlike conventional, lowpermeability designs, this cover relies on (1) the water storage capacity of a 163-cm soil “sponge” layer overlying a sand-and-gravel capillary barrier to retain precipitation while plants are dormant and (2) native vegetation to remove precipitation during the growing season. The sponge layer consists of a clay loam subsoil compacted to 1.65 g/cm2 in one lysimeter and a loam topsoil compacted to 1.45 g/cm2 in the other lysimeter, representing the range of as-built conditions constructed in the nearby disposal cell cover. About 0.1 mm of drainage occurred in both lysimeters during an average precipitation year and before they were planted, an amount well below the EPA target of <3.0 mm/yr. However, the cover with less compacted loam topsoil sponge had a 40% greater water storage capacity than the cover with overly compacted clay loam subsoil sponge. The difference is attributable in part to higher green leaf area and water extraction by plants in the loam topsoil. The lesson learned is that seemingly subtle differences in soil types, sources, and compaction can result in salient differences in performance. Diverse, seeded communities of

Changes in the Vegetation Cover in a Constructed Wetland at Argonne National Laboratory, Illinois

Energy Technology Data Exchange (ETDEWEB)

Bergman, C.L.; LaGory, K.

2004-01-01

Wetlands are valuable resources that are disappearing at an alarming rate. Land development has resulted in the destruction of wetlands for approximately 200 years. To combat this destruction, the federal government passed legislation that requires no net loss of wetlands. The United States Army Corps of Engineers (USACE) is responsible for regulating wetland disturbances. In 1991, the USACE determined that the construction of the Advanced Photon Source at Argonne National Laboratory would damage three wetlands that had a total area of one acre. Argonne was required to create a wetland of equal acreage to replace the damaged wetlands. For the first five years after this wetland was created (1992-1996), the frequency of plant species, relative cover, and water depth was closely monitored. The wetland was not monitored again until 2002. In 2003, the vegetation cover data were again collected with a similar methodology to previous years. The plant species were sampled using quadrats at randomly selected locations along transects throughout the wetland. The fifty sampling locations were monitored once in June and percent cover of each of the plant species was determined for each plot. Furthermore, the extent of standing water in the wetland was measured. In 2003, 21 species of plants were found and identified. Eleven species dominated the wetland, among which were reed canary grass (Phalaris arundinacea), crown vetch (Coronilla varia), and Canada thistle (Cirsium arvense). These species are all non-native, invasive species. In the previous year, 30 species were found in the same wetland. The common species varied from the 2002 study but still had these non-native species in common. Reed canary grass and Canada thistle both increased by more than 100% from 2002. Unfortunately, the non-native species may be contributing to the loss of biodiversity in the wetland. In the future, control measures should be taken to ensure the establishment of more desired native species.

Effect of Cover Crop Residues on Some Physicochemical Properties of Soil and Emergence Rate of Potato

Directory of Open Access Journals (Sweden)

M. Ghaffari

2012-07-01

Full Text Available The aim of this study, was to evaluate the effect of winter cover crop residues on speed of seed  potato emergence and percentage of organic carbon, soil specific weight and soil temperature. An experiment was carried out at the Research Farm of Agriculture Faculty, Bu-AliSinaUniversity, in 2008-2009. The experiment was a randomized complete block design with three replications. Winter cover crops consisted of rye, barley and oilseed rape, each one with common plant density (rye and barley at 190 kg.ha-1 and oilseed rape at 9 kg.ha-1 and triple plant densities(rye and barley 570 kg.ha-1 and oilseed rape, 27 kg.ha-1 and control (without cover crop. The results showed that rye and barley with triple plant densities produced higher biomass (1503.5 and 1392.2 g/m2, respectively than other treatments.Soil physicochemical properties were affected significantly by using cover crops. Rye, barley, and oilseed rape with triple rate and rye with common rape of plant densities produced, the highest organic carbon. Green manure of rye and barley with triple and rye with common rate plant densities, reduced soil specific weights by 17.3, 18 and 18 percent as compared with the control treatment (without cover crop planting. Rye and barley with triple plant densities increased average soil temperature by 12 and 11 percent respectively in comparison with control treatment. These treatments increased speed of seed potato emergence by 20 and 12 percent respectively as compared with that of control treatment, respectively. Other treatments showed no significant difference as compared to control. Cover crop residues increased plants speed of seed potato emergence through improving soil conditions.

Effects of Cover Crops on the Movement and Fate of Soil-Applied 14C-Fonofos in a Soil-Plant-Water Microcosm

International Nuclear Information System (INIS)

Liang, T.T.; Lichtenstein, E.P.

1981-01-01

Full text: The effects of corn plants or a ''lawn'' of ryegrass on the movement and metabolism of soil-applied 14 C-(ring)-fonofos were studied in a microcosm which consisted of terrestrial and aquatic components. Artificial rain, applied to the fallow or plant covered soils, resulted in runoff that accumulated in aquaria containing lake bottom mud and aquatic organisms. The presence and the type of a cover crop had a considerable effect on the mobility and metabolism of soil—applied 14 C—fonofos. The insecticide plus its metabolites were least persistent in systems with fallow soils and most persistent in those with ryegrass. Within the terrestrial soil 14 C-compounds moved downwards and were also translocated via the root systems into the leaves of corn and ryegrass. Within the plant tops 86% of the recovered benzene—soluble 14 C-compounds were in the form of the detoxified methyl phenyl sulfone and 2% or less as fonofos. Rain caused a considerable runoff of fallow soil but much less of cropped soil into the aquaria. 14 C-compounds transported were primarily associated with the runoff soil and most of these were later found in the soil—lake mud sediments. 14 C—fonofos was the major constituent in soils and aquatic sediments while the major metabolite recovered from both the terrestrial and aquatic portion of the microcosm was methyl phenyl sulfone, its amounts ranging from 13% to 92% of all benzene—soluble radiocarbon. Relatively small amounts of the insecticidal oxygen analog of fonofos were recovered, the exception being in roots of corn and of ryegrass. (author)

MULCHES AND OTHER COVER MATERIALS TO REDUCE WEED GROWTH IN CONTAINER-GROWN NURSERY STOCK.

Science.gov (United States)

Rys, F; Van Wesemael, D; Van Haecke, D; Mechant, E; Gobin, B

2014-01-01

Due to the recent EU-wide implementation of Integrated Pest Management (IPM), alternative methods to reduce weed growth in container-grown nursery stock are needed to cut back the use of herbicides. Covering the upper layer of the substrate is known as a potential method to prevent or reduce weed growth in plant containers. As a high variety of mulches and other cover materials are on the market, however, it is no longer clear for growers which cover material is most efficient for use in containers. Therefore, we examined the effect on weed growth of different mulches and other cover materials, including Pinus maritima, P. sylvestris, Bio-Top Basic, Bio-Top Excellent, coco chips fine, hemp fibres, straw pellets, coco disk 180LD and jute disk. Cover materials were applied immediately after repotting of Ligustrum ovalifolium or planting of Fagus sylvatica. At regular times, both weed growth and side effects (e.g., plant growth, water status of the substrate, occurrence of mushrooms, foraging of birds, complete cover of the substrate and fixation) were assessed. All examined mulches or other cover materials were able to reduce weed growth on the containers during the whole growing season. Weed suppression was even better than that of a chemical treated control. Although all materials showed some side effects, the impact on plant growth is most important to the grower and depends not only on material characteristics (e.g., biodegradation, nutrient leaching and N-immobilisation) but also on container size and climatic conditions. In conclusion, mulches and other cover materials can be a valuable tool within IPM to lower herbicide use. To enable a deliberate choice of which cover material is best used in a specific situation more research is needed on lifespan and stability as well as on economic characteristics of the materials.

Effects of vegetation and soil-surface cover treatments on the hydrologic behavior of low-level waste trench caps

International Nuclear Information System (INIS)

Lopez, E.A.; Barnes, F.J.; Antonio, E.J.

1988-01-01

Preliminary results are presented on a three-year field study at Los Alamos National Laboratory to evaluate the influence of different low-level radioactive waste trench cap designs on water balance under natural precipitation. Erosion plots having two different vegetative covers (shrubs and grasses) and with either gravel-mulched or unmulched soil surface treatments have been established on three different soil profiles on a decommissioned waste site. Total runoff and soil loss from each plot is measured after each precipitation event. Soil moisture is measured biweekly while plant canopy cover is measured seasonally. Preliminary results from the first year show that the application of a gravel mulch reduced runoff by 73 to 90%. Total soil loss was reduced by 83 to 93% by the mulch treatment. On unmulched plots, grass cover reduced both runoff and soil loss by about 50% compared to the shrub plots. Continued monitoring of the study site will provide data that will be used to analyze complex interactions between independent variables such rainfall amount and intensity, antecedent soil moisture, and soil and vegetation factors, as they influence water balance, and soil erosion. 18 refs., 2 figs., 3 tabs

Sediment balance in four small catechumen's with different land cover in the Central Pyrenes (Spain)

Energy Technology Data Exchange (ETDEWEB)

Nadal Romero, E.; Lana-Renault, N.; Serrano-Muela, P.; Reguez, D.; Alvera, B.; Latron, J.; Marti-Bono, C.; Garcia-Ruiz, J. M.

2009-07-01

Four experimental catchment s in the Central Pyrenes were monitored by the Department of Geo-environmental Processes and global Change (Pyrenean Institute of Ecology, CSIC) to assess the hydrological and geomprophological consequences of various land uses and vegetation cover. The catchments were selected along an attitudinal and land-use gradient and included: (i) a sub-Mediterranean environment affected by intense weathering and erosion processes on marls, (ii) an old abandoned cultivated area undergoing vegetation regrowth, (iii) a barely-disturbed forest area, and (iv) a sub-alpine grassland in the high mountains, affected by snow accumulation and melting processes. The results demonstrate that plant cover is a key factor influencing the suspended sediment concentration, total sediment yield and proportion of different types of sediment. (Author) 7 refs.

Thrips (Thysanoptera: Thripidae) mitigation in seedling cotton using strip tillage and winter cover crops.

Science.gov (United States)

Toews, Michael D; Tubbs, R Scott; Wann, Dylan Q; Sullivan, Dana

2010-10-01

Thrips are the most consistent insect pests of seedling cotton in the southeastern United States, where symptoms can range from leaf curling to stand loss. In a 2 year study, thrips adults and immatures were sampled at 14, 21 and 28 days after planting on cotton planted with a thiamethoxam seed treatment in concert with crimson clover, wheat or rye winter cover crops and conventional or strip tillage to investigate potential differences in thrips infestations. Densities of adult thrips, primarily Frankliniella fusca (Hinds), peaked on the first sampling date, whereas immature densities peaked on the second sampling date. Regardless of winter cover crop, plots that received strip tillage experienced significantly fewer thrips at each sampling interval. In addition, assessment of percentage ground cover 42 days after planting showed that there was more than twice as much ground cover in the strip-tilled plots compared with conventionally tilled plots. Correlation analyses showed that increased ground cover was inversely related to thrips densities that occurred on all three sampling dates in 2008 and the final sampling date in 2009. Growers who utilize strip tillage and a winter cover crop can utilize seed treatments for mitigation of early-season thrips infestation.

Plant sterol ester diet supplementation increases serum plant sterols and markers of cholesterol synthesis, but has no effect on total cholesterol levels.

Science.gov (United States)

Weingärtner, Oliver; Bogeski, Ivan; Kummerow, Carsten; Schirmer, Stephan H; Husche, Constanze; Vanmierlo, Tim; Wagenpfeil, Gudrun; Hoth, Markus; Böhm, Michael; Lütjohann, Dieter; Laufs, Ulrich

2017-05-01

This double-blind, randomized, placebo-controlled, cross-over intervention-study was conducted in healthy volunteers to evaluate the effects of plant sterol ester supplemented margarine on cholesterol, non-cholesterol sterols and oxidative stress in serum and monocytes. Sixteen volunteers, average age 34 years, with no or mild hypercholesterolemia were subjected to a 4 week period of daily intake of 3g plant sterols per day supplied via a supplemented margarine on top of regular eating habits. After a wash-out period of one week, volunteers switched groups. Compared to placebo, a diet supplementation with plant sterols increased serum levels of plant sterols such as campesterol (+0.16±0.19mg/dL, p=0.005) and sitosterol (+0.27±0.18mg/dL, psynthesis such as desmosterol (+0.05±0.07mg/dL, p=0.006) as well as lathosterol (+0.11±0.16mg/dL, p=0.012). Cholesterol serum levels, however, were not changed significantly (+18.68±32.6mg/dL, p=0.052). These findings could not be verified in isolated circulating monocytes. Moreover, there was no effect on monocyte activation and no differences with regard to redox state after plant sterol supplemented diet. Therefore, in a population of healthy volunteers with no or mild hypercholesterolemia, consumption of plant sterol ester supplemented margarine results in increased concentrations of plant sterols and cholesterol synthesis markers without affecting total cholesterol in the serum, activation of circulating monocytes or redox state. Copyright © 2016 Elsevier Ltd. All rights reserved.

Special study on vegetative covers

International Nuclear Information System (INIS)

1988-11-01

This report describes the findings of a special study on the use of vegetative covers to stabilize tailings piles for the Uranium Mill Tailings Remedial Action (UMTRA) Project. The principal rationale for using plants would be to establish a dynamic system for controlling water balance. Specifically, vegetation would be used to intercept and transpire precipitation to the atmosphere, rather than allowing water to drain into the tailings and mobilize contaminants. This would facilitate compliance with groundwater standards proposed for the UMTRA Project by the Environmental Protection Agency. The goals of the study were to evaluate the feasibility of using vegetative covers on UMTRA Project piles, define the advantages and disadvantages of vegetative covers, and develop general guidelines for their use when such use seems reasonable. The principal method for the study was to analyze and apply to the UMTRA Project the results of research programs on vegetative covers at other US Department of Energy (DOE) waste management facilities. The study also relied upon observations made of existing stabilized piles at UMTRA Project sites where natural vegetation is growing on the rock-covered surfaces. Water balance and erosion models were also used to quantify the long-term performance of vegetative covers planned for the topslopes of stabilized piles at Grand Junction and Durango, Colorado, two UMTRA Project sites where the decision was made during the course of this special study to use vegetative covers. Elements in the design and construction of the vegetative covers at these two sites are discussed in the report, with explanations of the differing features that reflect differing environmental conditions. 28 refs., 18 figs., 9 tabs

Environmental monitoring report for Pantex Plant covering 1986

International Nuclear Information System (INIS)

Laseter, W.A.

1987-04-01

This report summarizes the environmental monitoring program at Pantex Plant for 1986. It has been prepared in accordance with the US Department of Energy Order 5484.1. This report presents monitoring data for both radioactive and nonradioactive species in the local environment. Plant activities involve the handling of significant quantities of uranium, plutonium and tritium in the form of completed parts received from other DOE facilities, resulting in a very low potential for release of these radionuclides to the atmosphere. In 1986 only small releases of depleted uranium (depleted in the isotope U-235) and tritium occurred which could have affected the local environment. Monitoring data indicate that concentrations of these nuclides in the environment are below established criteria for air and water and therefore should not present a health hazard either to employees or to the public

C and N accumulations in soil aggregates determine nitrous oxide emissions from cover crop treated rice paddy soils during fallow season

Energy Technology Data Exchange (ETDEWEB)

Pramanik, Prabhat, E-mail: prabhat2003@gmail.com; Haque, Md. Mozammel; Kim, Sang Yoon; Kim, Pil Joo, E-mail: pjkim@gnu.ac.kr

2014-08-15

Combination of leguminous and non-leguminous plant residues are preferably applied in rice paddy soils to increase the rate of organic matter mineralization and to improve plant growth. However, organic matter addition facilitates methane (CH{sub 4}) emission from rice paddy soil. Mineralization of organic nitrogen (N) increases NO{sub 3}–N concentrations in soil, which are precursors for the formation of nitrous oxide (N{sub 2}O). However, N{sub 2}O is a minor greenhouse gas emitted from submerged rice field and hence is not often considered during calculation of total global warming potential (GWP) during rice cultivation. The hypothesis of this study was that fluxes of N{sub 2}O emissions might be changed after removal of flooded water from rice field and the effect of cover crops on N{sub 2}O emissions in the fallow season might be interesting. However, the effects of N-rich plant residues on N{sub 2}O emission rates in the fallow season and its effect on annual GWP were not studied before. In this experiment, combination of barley (non-leguminous) and hairy vetch (leguminous) biomasses were applied at 9 Mg ha{sup −1} and 27 Mg ha{sup −1} rates in rice paddy soil. Cover crop application significantly increased CH{sub 4} emission flux while decreased N{sub 2}O emissions during rice cultivation. The lowest N{sub 2}O emission was observed in 27 Mg ha{sup −1} cover crop treated plots. Cover crop applications increased N contents in soil aggregates especially in smaller aggregates (< 250 μm), and that proportionately increased the N{sub 2}O emission potentials of these soil aggregates. Fluxes of N{sub 2}O emissions in the fallow season were influenced by the N{sub 2}O emission potentials of soil aggregates and followed opposite trends as those observed during rice cultivation. Therefore, it could be concluded that the doses of cover crop applications for rice cultivation should not be optimized considering only CH{sub 4}, but N{sub 2}O should also be

Weed Control with Cover Crops in Irrigated Potatoes

Directory of Open Access Journals (Sweden)

G.H. Mehring

2016-01-01

Full Text Available Field experiments at Oakes, ND, USA in 2010 and Carrington, ND, USA in 2011 were conducted to evaluate the potential for cover crops grown in the Northern Great Plains, USA in order to reduce weed emergence and density in irrigated potatoes. Treatments included five cover crop treatments and three cover crop termination treatments. Termination of cover crops was done with glyphosate, disk-till, and roto-till. Cover crop biomass accumulation was greatest for rye/canola and triticale at Oakes, and hairy vetch and hairy vetch/rye at Carrington. Cover crop and termination affected weed control 14, 29, and 51 days after planting (DAP at Oakes. Weed control at Carrington was at least 90% for all cover crop and termination treatments at all three evaluation timings. Marketable yield at Oakes was greater when roto-till was used to terminate the cover crops compared with disk-till or herbicide, which is beneficial for organic systems where herbicides are not used. Marketable yield at Carrington was not affected by cover crop or termination treatments. Results suggest that cover crops can successfully be integrated into irrigated potato production for weed control with yields equal to no cover crop, and with attention to potential mechanical difficulties.

Examination of the semi-automatic calculation technique of vegetation cover rate by digital camera images.

Science.gov (United States)

Takemine, S.; Rikimaru, A.; Takahashi, K.

The rice is one of the staple foods in the world High quality rice production requires periodically collecting rice growth data to control the growth of rice The height of plant the number of stem the color of leaf is well known parameters to indicate rice growth Rice growth diagnosis method based on these parameters is used operationally in Japan although collecting these parameters by field survey needs a lot of labor and time Recently a laborsaving method for rice growth diagnosis is proposed which is based on vegetation cover rate of rice Vegetation cover rate of rice is calculated based on discriminating rice plant areas in a digital camera image which is photographed in nadir direction Discrimination of rice plant areas in the image was done by the automatic binarization processing However in the case of vegetation cover rate calculation method depending on the automatic binarization process there is a possibility to decrease vegetation cover rate against growth of rice In this paper a calculation method of vegetation cover rate was proposed which based on the automatic binarization process and referred to the growth hysteresis information For several images obtained by field survey during rice growing season vegetation cover rate was calculated by the conventional automatic binarization processing and the proposed method respectively And vegetation cover rate of both methods was compared with reference value obtained by visual interpretation As a result of comparison the accuracy of discriminating rice plant areas was increased by the proposed

Toxicity of arsenic (III) and (V) on plant growth, element uptake, and total amylolytic activity of mesquite (Prosopis juliflora x P. velutina).

Science.gov (United States)

Mokgalaka-Matlala, Ntebogeng S; Flores-Tavizón, Edith; Castillo-Michel, Hiram; Peralta-Videa, Jose R; Gardea-Torresdey, Jorge L

2008-01-01

The effects of arsenite [As(III)] and arsenate [As(V)] on the growth of roots, stems, and leaves and the uptake of arsenic (As), micro- and macronutrients, and total amylolytic activity were investigated to elucidate the phytotoxicity of As to the mesquite plant (Prosopis juliflora x P. velutina). The plant growth was evaluated by measuring the root and shoot length, and the element uptake was determined using inductively coupled plasma optical emission spectroscopy. The root and leaf elongation decreased significantly with increasing As(III) and As(V) concentrations; whereas, stem elongation remained unchanged. The As uptake increased with increasing As(III) or As(V) concentrations in the medium. Plants treated with 50 mg/L As(III) accumulated up to 920 mg/kg dry weight (d wt) in roots and 522 mg/kg d wt in leaves, while plants exposed to 50 mg/L As(V) accumulated 1980 and 210 mg/kg d wt in roots and leaves, respectively. Increasing the As(V) concentration up to 20 mg/L resulted in a decrease in the total amylolytic activity. On the contrary, total amylolytic activity in As(III)-treated plants increased with increasing As concentration up to 20 mg/L. The macro- and micronutrient concentrations changed in As-treated plants. In shoots, Mo and K were reduced but Ca was increased, while in roots Fe and Ca were increased but K was reduced. These changes reduced the size of the plants, mainly in the As(III)-treated plants; however, there were no visible sign of As toxicity.

Measuring competition in plant communities where it is difficult to distinguish individual plants

DEFF Research Database (Denmark)

Damgaard, Christian

2011-01-01

A novel method for measuring plant-plant interactions in undisturbed semi-natural and natural plant communities where it is difficult to distinguish individual plants is discussed. It is assumed that the ecological success of the different plant species in the plant community may be adequately...... measured by plant cover and vertical density (a measure that is correlated to the 3-dimensional space occupancy and biomass). Both plant cover and vertical density are measured in a standard pin-point analysis in the beginning and at the end of the growing season. In the outlined competition model....... The method allows direct measurements of the competitive effects of neighbouringzplants on plant performance and the estimation of parameters that describe the ecological processes of plantplant interactions during the growing season as well as the process of survival and recruitment between growing seasons...

Cover Crops for Managing Stream Water Quantity and Improving Stream Water Quality of Non-Tile Drained Paired Watersheds

Directory of Open Access Journals (Sweden)

Gurbir Singh

2018-04-01

Full Text Available In the Midwestern United States, cover crops are being promoted as a best management practice for managing nutrient and sediment losses from agricultural fields through surface and subsurface water movement. To date, the water quality benefits of cover crops have been inferred primarily from plot scale studies. This project is one of the first to analyze the impacts of cover crops on stream water quality at the watershed scale. The objective of this research was to evaluate nitrogen, phosphorus, and sediment loss in stream water from a no-till corn-soybean rotation planted with winter cover crops cereal rye (Secale cereale and hairy vetch (Vicia villosa in non-tile drained paired watersheds in Illinois, USA. The paired watersheds are under mixed land use (agriculture, forest, and pasture. The control watershed had 27 ha of row-crop agriculture, and the treatment watershed had 42 ha of row crop agriculture with cover crop treatment (CC-treatment. During a 4-year calibration period, 42 storm events were collected and Event Mean Concentrations (EMCs for each storm event were calculated for total suspended solids (TSS, nitrate-N (NO3-N, ammonia-N (NH4-N, dissolved reactive phosphorus (DRP, and total discharge. Predictive regression equations developed from the calibration period were used for calculating TSS, NO3-N, NH4-N, and DRP losses of surface runoff for the CC-treatment watershed. The treatment period consisted of total 18 storm events, seven of which were collected during the cereal rye, eight in the hairy vetch cover crop season and three during cash crop season. Cover crops reduced TSS and discharge by 33% and 34%, respectively in the CC-treatment watershed during the treatment period. However, surprisingly, EMCs for NO3-N, NH4-N, and DRP did not decrease. Stream discharge from the paired-watersheds will continue to be monitored to determine if the current water quality results hold or new patterns emerge.

Design and testing of botanical thermotropic actuator mechanisms in thermally adaptive building coverings

Science.gov (United States)

Barrett, Ronald M.; Barrett, Ronald P.; Barrett, Cassandra M.

2017-09-01

This paper lays out the inspiration, operational principles, analytical modeling and coupon testing of a new class of thermally adaptive building coverings. The fundamental driving concepts for these coverings are derived from various families of thermotropic plant structures. Certain plant cellular structures like those in Mimosa pudica (Sensitive Plant), Rhododendron leaves or Albizia julibrissin (Mimosa Tree), exhibit actuation physiology which depends on changes in cellular turgor pressures to generate motion. This form of cellular action via turgor pressure manipulation is an inspiration for a new field of thermally adaptive building coverings which use various forms of cellular foam to aid or enable actuation much like plant cells are used to move leaves. When exposed to high solar loading, the structures use the inherent actuation capability of pockets of air trapped in closed cell foam as actuators to curve plates upwards and outwards. When cold, these same structures curve back towards the building forming large convex pockets of dead air to insulate the building. This paper describes basic classical laminated plate theory models comparing theory and experiment of such coupons containing closed-cell foam actuators. The study concludes with a global description of the effectiveness of this class of thermally adaptive building coverings.

Swine manure injection with low-disturbance applicator and cover crops reduce phosphorus losses.

Science.gov (United States)

Kovar, J L; Moorman, T B; Singer, J W; Cambardella, C A; Tomer, M D

2011-01-01

Injection of liquid swine manure disturbs surface soil so that runoff from treated lands can transport sediment and nutrients to surface waters. We determined the effect of two manure application methods on P fate in a corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] production system, with and without a winter rye (Secale cereale L.)-oat (Avena sativa L.) cover crop. Treatments included: (i) no manure; (ii) knife injection; and (iii) low-disturbance injection, each with and without the cover crop. Simulated rainfall runoff was analyzed for dissolved reactive P (DRP) and total P (TP). Rainfall was applied 8 d after manure application (early November) and again in May after emergence of the corn crop. Manure application increased soil bioavailable P in the 20- to 30-cm layer following knife injection and in the 5- to 20-cm layer following low-disturbance injection. The low-disturbance system caused less damage to the cover crop, so that P uptake was more than threefold greater. Losses of DRP were greater in both fall and spring following low-disturbance injection; however, application method had no effect on TP loads in runoff in either season. The cover crop reduced fall TP losses from plots with manure applied by either method. In spring, DRP losses were significantly higher from plots with the recently killed cover crop, but TP losses were not affected. Low-disturbance injection of swine manure into a standing cover crop can minimize plant damage and P losses in surface runoff while providing optimum P availability to a subsequent agronomic crop.

488-D Ash Basin Vegetative Cover Treatibility Study

Energy Technology Data Exchange (ETDEWEB)

Barton, Christopher; Marx, Don; Blake, John; Adriano, Domy; Koo, Bon-Jun; Czapka, Stephen

2003-01-01

The 488-D Ash Basin is an unlined containment basin that received ash and coal reject material from the operation of a powerhouse at the USDOE's Savannah River Site, SC. They pyretic nature of the coal rejects has resulted in the formation of acidic drainage (AD), which has contributed to groundwater deterioration and threatens biota in down gradient wetlands. Establishment of a vegetative cover was examined as a remedial alternative for reducing AD generation within this system by enhanced utilization of rainwater and subsequent non-point source water pollution control. The low nutrient content, high acidity, and high salinity of the basin material, however, was deleterious to plant survivability. As such, studies to identify suitable plant species and potential adaptations, and pretreatment techniques in the form of amendments, tilling, and/or chemical stabilization were needed. A randomized block design consisting of three subsurface treatments (blocks) and five duplicated surface amendments (treatments) was developed. One hundred inoculated pine trees were planted on each plot. Herbaceous species were also planted on half of the plots in duplicated 1-m2 beds. After two growing seasons, deep ripping, subsurface amendments and surface covers were shown to be essential for the successful establishment of vegetation on the basin. This is the final report of the study.

Urban Rights-of-Way as Reservoirs for Tall-Grass Prairie Plants and Butterflies

Science.gov (United States)

Leston, Lionel; Koper, Nicola

2016-03-01

Urban rights-of-way may be potential reservoirs of tall-grass prairie plants and butterflies. To determine if this is true, in 2007-2008, we conducted vegetation surveys of species richness and cover, and butterfly surveys of species richness and abundance, along 52 transmission lines and four remnant prairies in Winnipeg, Manitoba. We detected many prairie plants and butterflies within transmission lines. Some unmowed and infrequently managed transmission lines had native plant species richness and total percent cover of native plants comparable to that of similar-sized remnant tall-grass prairies in the region. Although we did not find significant differences in overall native butterfly numbers or species richness between rights-of-way and remnant prairies, we found lower numbers of some prairie butterflies along frequently mowed rights-of-way than within remnant tall-grass prairies. We also observed higher butterfly species richness along sites with more native plant species. By reducing mowing and spraying and reintroducing tall-grass prairie plants, urban rights-of-way could serve as extensive reservoirs for tall-grass prairie plants and butterflies in urban landscapes. Eventually, managing urban rights-of-way as reservoirs for tall-grass prairie plants and animals could contribute to the restoration of tall-grass prairie in the North American Midwest.

Urban Rights-of-Way as Reservoirs for Tall-Grass Prairie Plants and Butterflies.

Science.gov (United States)

Leston, Lionel; Koper, Nicola

2016-03-01

Urban rights-of-way may be potential reservoirs of tall-grass prairie plants and butterflies. To determine if this is true, in 2007-2008, we conducted vegetation surveys of species richness and cover, and butterfly surveys of species richness and abundance, along 52 transmission lines and four remnant prairies in Winnipeg, Manitoba. We detected many prairie plants and butterflies within transmission lines. Some unmowed and infrequently managed transmission lines had native plant species richness and total percent cover of native plants comparable to that of similar-sized remnant tall-grass prairies in the region. Although we did not find significant differences in overall native butterfly numbers or species richness between rights-of-way and remnant prairies, we found lower numbers of some prairie butterflies along frequently mowed rights-of-way than within remnant tall-grass prairies. We also observed higher butterfly species richness along sites with more native plant species. By reducing mowing and spraying and reintroducing tall-grass prairie plants, urban rights-of-way could serve as extensive reservoirs for tall-grass prairie plants and butterflies in urban landscapes. Eventually, managing urban rights-of-way as reservoirs for tall-grass prairie plants and animals could contribute to the restoration of tall-grass prairie in the North American Midwest.

Coastal regime shifts: rapid responses of coastal wetlands to changes in mangrove cover.

Science.gov (United States)

Guo, Hongyu; Weaver, Carolyn; Charles, Sean P; Whitt, Ashley; Dastidar, Sayantani; D'Odorico, Paolo; Fuentes, Jose D; Kominoski, John S; Armitage, Anna R; Pennings, Steven C

2017-03-01

Global changes are causing broad-scale shifts in vegetation communities worldwide, including coastal habitats where the borders between mangroves and salt marsh are in flux. Coastal habitats provide numerous ecosystem services of high economic value, but the consequences of variation in mangrove cover are poorly known. We experimentally manipulated mangrove cover in large plots to test a set of linked hypotheses regarding the effects of changes in mangrove cover. We found that changes in mangrove cover had strong effects on microclimate, plant community, sediment accretion, soil organic content, and bird abundance within 2 yr. At higher mangrove cover, wind speed declined and light interception by vegetation increased. Air and soil temperatures had hump-shaped relationships with mangrove cover. The cover of salt marsh plants decreased at higher mangrove cover. Wrack cover, the distance that wrack was distributed from the water's edge, and sediment accretion decreased at higher mangrove cover. Soil organic content increased with mangrove cover. Wading bird abundance decreased at higher mangrove cover. Many of these relationships were non-linear, with the greatest effects when mangrove cover varied from zero to intermediate values, and lesser effects when mangrove cover varied from intermediate to high values. Temporal and spatial variation in measured variables often peaked at intermediate mangrove cover, with ecological consequences that are largely unexplored. Because different processes varied in different ways with mangrove cover, the "optimum" cover of mangroves from a societal point of view will depend on which ecosystem services are most desired. © 2016 by the Ecological Society of America.

Plant air systems safety study: Portsmouth Gaseous Diffusion Plant

International Nuclear Information System (INIS)

1982-05-01

The Portsmouth Gaseous Diffusion Plant Air System facilities and operations are reviewed for potential safety problems not covered by standard industrial safety procedures. Information is presented under the following section headings: facility and process description (general); air plant equipment; air distribution system; safety systems; accident analysis; plant air system safety overview; and conclusion

Database for estimating tree responses of walnut and other hardwoods to ground cover management practices

Science.gov (United States)

J.W. Van Sambeek

2010-01-01

The ground cover in plantings of walnut and other hardwoods can substantially affect tree growth and seed production. The number of alternative ground covers that have been suggested for establishment in tree plantings far exceeds the number that have already been tested with walnut and other temperate hardwoods. Knowing how other hardwood species respond to ground...

Main Characteristics of Nuclear Power Plants in the European Union and Candidate Countries

International Nuclear Information System (INIS)

Lillington, J.N.; Turland, B.D.; Haste, T.J.; Seiler, J.M.; Tapia, J.; Carretero, A.; Perez, T.; Geutges, A.; Sehgal, B.R.; Mattila, L.; Holmstrom, H.; Karwat, H.; Maroti, L.; Husarcek, J.

2001-10-01

The main objective was to advise the EC on future challenges and opportunities in terms of enhanced co-operation in the area of nuclear safety and harmonization of safety requirements and practices in an enlarged European Union Part of this activity was to provide a summary of the plant characteristics of the operating civil nuclear power plants in the EU Member and Candidate Countries. The present report provides these data in three formats: A reference table which lists the main characteristics of nuclear power-producing reactors operating in the European Union (EU) and Candidate Countries, as at 31 December 1999. Also included, for the sake of completeness, are data for reactors in the former Soviet Union, such as Russia and the Ukraine. The format adopted follows that in the annual International Atomic Energy Agency (IAEA) reference data report ''Nuclear Power Reactors of the World'', from which much of the information was taken; A summary table indicating totals by reactor type covering Western and Eastern Europe separately, again from IAEA sources, giving number of plant, total generating capacity and total years in operation. A list of the abbreviations for different reactor types is also provided; A set of detailed data sheets giving main plant characteristics for different reactor types ordered by country. These data sheets cover reactors in EU Member and Candidate Countries only. Details are provided on the origin of the data where these are available, so that further information may be obtained if desired and where permitted by commercial and/or proprietary considerations. (author)

Evaluating Methods for Isolating Total RNA and Predicting the Success of Sequencing Phylogenetically Diverse Plant Transcriptomes

Science.gov (United States)

Bruskiewich, Richard; Burris, Jason N.; Carrigan, Charlotte T.; Chase, Mark W.; Clarke, Neil D.; Covshoff, Sarah; dePamphilis, Claude W.; Edger, Patrick P.; Goh, Falicia; Graham, Sean; Greiner, Stephan; Hibberd, Julian M.; Jordon-Thaden, Ingrid; Kutchan, Toni M.; Leebens-Mack, James; Melkonian, Michael; Miles, Nicholas; Myburg, Henrietta; Patterson, Jordan; Pires, J. Chris; Ralph, Paula; Rolf, Megan; Sage, Rowan F.; Soltis, Douglas; Soltis, Pamela; Stevenson, Dennis; Stewart, C. Neal; Surek, Barbara; Thomsen, Christina J. M.; Villarreal, Juan Carlos; Wu, Xiaolei; Zhang, Yong; Deyholos, Michael K.; Wong, Gane Ka-Shu

2012-01-01

Next-generation sequencing plays a central role in the characterization and quantification of transcriptomes. Although numerous metrics are purported to quantify the quality of RNA, there have been no large-scale empirical evaluations of the major determinants of sequencing success. We used a combination of existing and newly developed methods to isolate total RNA from 1115 samples from 695 plant species in 324 families, which represents >900 million years of phylogenetic diversity from green algae through flowering plants, including many plants of economic importance. We then sequenced 629 of these samples on Illumina GAIIx and HiSeq platforms and performed a large comparative analysis to identify predictors of RNA quality and the diversity of putative genes (scaffolds) expressed within samples. Tissue types (e.g., leaf vs. flower) varied in RNA quality, sequencing depth and the number of scaffolds. Tissue age also influenced RNA quality but not the number of scaffolds ≥1000 bp. Overall, 36% of the variation in the number of scaffolds was explained by metrics of RNA integrity (RIN score), RNA purity (OD 260/230), sequencing platform (GAIIx vs HiSeq) and the amount of total RNA used for sequencing. However, our results show that the most commonly used measures of RNA quality (e.g., RIN) are weak predictors of the number of scaffolds because Illumina sequencing is robust to variation in RNA quality. These results provide novel insight into the methods that are most important in isolating high quality RNA for sequencing and assembling plant transcriptomes. The methods and recommendations provided here could increase the efficiency and decrease the cost of RNA sequencing for individual labs and genome centers. PMID:23185583

Availability of thermal power plants 1977-1986

International Nuclear Information System (INIS)

Nitsch, D.; Schmitz, H.

1987-01-01

To get a picture of power plant availability and its influencing factors, availability data have been acquired and evaluated by VGB according to different design and operation parameters since 1970. The present volume is the 16th annual statistics since 1970. It covers the decade of 1977 to 1986 and contains availability data of 384 power plants in Germany and abroad, with a total of 94.896 MW and 3.768 plant years. Data are presented on fossil-fuelled units, units with a combined gas/steam cycle, nuclear power plants and gas turbine systems, with further sub-categories according to unit size, fuel, type, years of operation, and operating regime. German plants are reviewed separately. All power data are gross data measured at the generator terminals. For a comparative evaluation, the data of 1986 are supplemented by yearly averages since 1977 and averages for the decade from 1977 to 1986. Since 1978, nonavailability data are categorized as 'unscheduled' and 'scheduled' nonavailabilities. For availability data of 1970 to 1976, see the VGB publication 'Availability of thermal power plants, 1970 to 1981'. (orig./UA) [de

The effect of plant growth promoting rhizobacteria (PGPR on quantitative and qualitative characteristics of Sesamum indicum L. with application of cover crops of Lathyrus sp. and Persian clover (Trifolium resopinatum L.

Directory of Open Access Journals (Sweden)

M. Jahan

2016-05-01

Full Text Available Cover crops cultivation and application of plant growth rhizobacteria are the key factors to enhance agroecosystem health. A field experiment was conducted at the Research Farm of Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, during growing season of 2009-2010. A split plot arrangement based on a complete randomized block design with three replications was used. Cultivation and no cultivation of Lathyrus sp. and Persian clover (Trifolium resopinatum in autumn assigned to the main plots. The sub plot factor consisted of three different types of biofertilizers plus control, including 1-nitroxin (containing of Azotobacter sp. and Azospirillum sp., 2- phosphate solubilizing bacteria (PSB (containing of Bacillus sp. and Pseudomonas sp., 3- biosulfur (containing of Thiobacillus ssp. and 4- control (no fertilizer. The results showed the effect of cover crops on seed number and seed weight per plant, biological and seed yield was significant, as the seed yield increased of 9 %. In general, biofertilizers showed superiority due to the most studied traits compared to control. Nitroxin, PSB and biosulfur increased biological yield of 44, 28 and 26 % compared to control, respectively. Cover crops and biofertilizers interactions, showed significant effect on all studied traits, as the highest and the lowest harvest index resulted in cover crop combined with biofertilizers (22.1% and cultivation and no cultivation of cover crops combined with control (15.3%, respectively. The highest seed oil and protein content resulted from cover crops plus biofertilizers (42.4% and cover crops plus PSB (22.5%, respectively. In general, the results showed cover crops cultivation in combination with biofertilizers application could be an ecological alternative for chemical fertilizers, in addition of achieving advantages of cover crops. According to the results, it should be possible to design an ecological cropping system and produce appropriate and healthy

Impacts of Cover Crops on Water and Nutrient Dynamics in Agroecosystems

Science.gov (United States)

Williard, K.; Swanberg, S.; Schoonover, J.

2013-05-01

Intensive cropping systems of corn (Zea Mays L.) and soybeans (Glycine max) are commonly leaky systems with respect to nitrogen (N). Reactive N outputs from agroecosystems can contribute to eutrophication and hypoxic zones in downstream water bodies and greenhouse gas (N2O) emissions. Incorporating cover crops into temperate agroecosystem rotations has been promoted as a tool to increase nitrogen use efficiency and thus limit reactive N outputs to the environment. Our objective was determine how cereal rye (Secale cereal L.) and annual ryegrass (Lolium multiflorum) cover crops impact nutrient and soil water dynamics in an intensive corn and soybean cropping rotation in central Illinois. Cover crops were planted in mid to late October and terminated in early April prior to corn or soybean planting. In the spring just prior to cover crop termination, soil moisture levels were lower in the cover crop plots compared to no cover plots. This can be a concern for the subsequent crop in relatively dry years, which the Midwestern United States experienced in 2012. No cover plots had greater nutrient leaching below the rooting zone compared to cover crop areas, as expected. The cover crops were likely scavenging nutrients during the fall and early spring and should provide nutrients to the subsequent crop via decomposition and mineralization of the cover crop residue. Over the long term, cover crop systems should produce greater inputs and cycling of carbon and N, increasing the productivity of crops due to the long-term accumulation of soil organic matter. This study demonstrates that there may be short term trade-offs in reduced soil moisture levels that should be considered alongside the long term nutrient scavenging and recycling benefits of cover crops.

Kenaf and cowpea as sugarcane cover crops

Science.gov (United States)

The use of cover crops during the fallow period prior to planting sugarcane has the potential to influence not only the following sugarcane crop, but the economics of the production system as a whole. Typically, a Louisiana sugarcane field is replanted every four years due to declining yields, and,...

Million trees Los Angeles canopy cover and benefit assessment

Science.gov (United States)

E.G. McPherson; J.R. Simpson; Q. Xiao; C. Wu

2011-01-01

The Million Trees LA initiative intends to improve Los Angeles’s environment through planting and stewardship of 1 million trees. The purpose of this study was to measure Los Angeles’s existing tree canopy cover (TCC), determine if space exists for 1 million additional trees, and estimate future benefits from the planting. High-resolution QuickBird remote sensing data...

Total phenolics and antioxidant activity of five medicinal plant; Fenois totais e atividade antioxidante de cinco plantas medicinais

Energy Technology Data Exchange (ETDEWEB)

Sousa, Cleyton Marcos de M.; Silva, Hilris Rocha e; Vieira-Junior, Gerardo Magela; Ayres, Mariane Cruz C.; Costa, Charllyton Luis S. da; Araajo, Delton Servulo; Cavalcante, Luis Carlos D.; Barros, Elcio Daniel S.; Araujo, Paulo Breitner de M.; Brandao, Marcela S.; Chaves, Mariana H. [Universidade Federal do Piaui, Teresina, PI (Brazil). Dept. de Quimica]. E-mail: mariana@ufpi.br

2007-03-15

This paper describes total phenolics content and antioxidant activity in the ethanolic extract of leaves, bark and roots of five medicinal plants: Terminalia brasiliensis Camb., Terminalia fagifolia Mart. and Zucc., Copernicia cerifera (Miller) H.E. Moore, Cenostigma macrophyllum Tul. var. acuminata Teles Freire and Qualea grandiflora Mart. The total phenolics content of the plant extracts, determined by the Folin-Ciocalteu method, varied from 250.0 {+-}8,2 to 763,63 {+-}13.03 mg of gallic acid equivalent/g dry EtOH extract. The antioxidant activity of extracts was evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay system. Extract of bark from T. brasiliensis, the most active, with an EC{sub 50} value of 27.59 {+-} 0.82 {mu}g/mL, was comparable to rutin (EC{sub 50} = 27.80 {+-} 1.38) and gallic acid (EC{sub 50} = 24.27 {+-} 0.31), used as positive controls. The relationship between total phenolic content and antioxidant activity was positive and significant for T. brasiliensis, C. macrophyllum and C. cerifera. (author)

Total and bioavailable arsenic concentration in arid soils and its uptake by native plants from the pre-Andean zones in Chile.

Science.gov (United States)

Díaz, O; Tapia, Y; Pastene, R; Montes, S; Núñez, N; Vélez, D; Montoro, R

2011-06-01

Arsenic is the most important contaminant of the environment in northern Chile. Soil samples and plant organs from three native plant species, Pluchea absinthioides, Atriplex atacamensis and Lupinus microcarpus, were collected from arid zones in order to determine the total and bioavailable arsenic concentrations in soils and to assess the bioconcentration factor (BCF) and transport index (Ti) of arsenic in the plants. Total arsenic concentrations in soils (pH 8.3-8.5) where A. atacamensis and P. absinthioides were collected, reached levels considered to be contaminated (54.3 ± 15.4 and 52.9 ± 9.9 mg kg⁻¹, respectively), and these values were approximately ten times higher than in soils (pH 7.6) where L. microcarpus was collected. Bioavailable arsenic ranged from 0.18 to 0.42% of total arsenic concentration. In the three plant species, arsenic concentration in leaves were significantly (p ≤ 0.05) higher than in roots. L. microcarpus showed the highest arsenic concentration in its leaves (9.7 ± 1.6 mg kg⁻¹) and higher values of BCF (1.8) and Ti (6.1), indicating that this species has a greater capacity to accumulate and translocate the metalloid to the leaf than do the other species.

Glass microspheres covering film: first field evaluations

International Nuclear Information System (INIS)

Magnani, G.; Filippi, F.

2006-01-01

A trial was carried out to evaluate, in the North-Centre of Italy, the behaviour in field of a new plastic covering film, prepared with the inclusion of empty glass microspheres (Solex). The trial was conducted on tomato (Lycopersicon esculentum L.) and eggplant (Solanum melongena L.). The new film was compared to a covering film with the same optical (diffuse light) and constitutional (co-extruded three layers EVA-WPE) characteristics. Since the first results, the innovative film showed a better behaviour than the control one. It presented light and thermal conditions (lower temperature during the day and slightly higher temperature in the night, compared to the control film) that allowed a better growth and yield than the control film. The growth analysis of tomato showed that plants grown under glass microsphere film had an higher growth rate (dry weight/days) and thickness of leaves compared to the control one. The yield of tomato and eggplant presented an increase in plants cultivated under the innovative film, especially for number and weight of fruits. The commercial quality did not show any differences between the films, except for the flesh hardness of tomato: this could be explained with the fact that the glass microspheres film provides environmental conditions avoiding plant stress during some stages of its cycle [it

Ethnomedicinal and ecological status of plants in Garhwal Himalaya, India

Science.gov (United States)

2011-01-01

Background The northern part of India harbours a great diversity of medicinal plants due to its distinct geography and ecological marginal conditions. The traditional medical systems of northern India are part of a time tested culture and honored still by people today. These traditional systems have been curing complex disease for more than 3,000 years. With rapidly growing demand for these medicinal plants, most of the plant populations have been depleted, indicating a lack of ecological knowledge among communities using the plants. Thus, an attempt was made in this study to focus on the ecological status of ethnomedicinal plants, to determine their availability in the growing sites, and to inform the communities about the sustainable exploitation of medicinal plants in the wild. Methods The ecological information regarding ethnomedicinal plants was collected in three different climatic regions (tropical, sub-tropical and temperate) for species composition in different forest layers. The ecological information was assessed using the quadrate sampling method. A total of 25 quadrats, 10 × 10 m were laid out at random in order to sample trees and shrubs, and 40 quadrats of 1 × 1 m for herbaceous plants. In each climatic region, three vegetation sites were selected for ecological information; the mean values of density, basal cover, and the importance value index from all sites of each region were used to interpret the final data. Ethnomedicinal uses were collected from informants of adjacent villages. About 10% of inhabitants (older, experienced men and women) were interviewed about their use of medicinal plants. A consensus analysis of medicinal plant use between the different populations was conducted. Results Across the different climatic regions a total of 57 species of plants were reported: 14 tree species, 10 shrub species, and 33 herb species. In the tropical and sub-tropical regions, Acacia catechu was the dominant tree while Ougeinia oojeinensis in the

Ethnomedicinal and ecological status of plants in Garhwal Himalaya, India

Directory of Open Access Journals (Sweden)

Sheikh Mehraj A

2011-10-01

Full Text Available Abstract Background The northern part of India harbours a great diversity of medicinal plants due to its distinct geography and ecological marginal conditions. The traditional medical systems of northern India are part of a time tested culture and honored still by people today. These traditional systems have been curing complex disease for more than 3,000 years. With rapidly growing demand for these medicinal plants, most of the plant populations have been depleted, indicating a lack of ecological knowledge among communities using the plants. Thus, an attempt was made in this study to focus on the ecological status of ethnomedicinal plants, to determine their availability in the growing sites, and to inform the communities about the sustainable exploitation of medicinal plants in the wild. Methods The ecological information regarding ethnomedicinal plants was collected in three different climatic regions (tropical, sub-tropical and temperate for species composition in different forest layers. The ecological information was assessed using the quadrate sampling method. A total of 25 quadrats, 10 × 10 m were laid out at random in order to sample trees and shrubs, and 40 quadrats of 1 × 1 m for herbaceous plants. In each climatic region, three vegetation sites were selected for ecological information; the mean values of density, basal cover, and the importance value index from all sites of each region were used to interpret the final data. Ethnomedicinal uses were collected from informants of adjacent villages. About 10% of inhabitants (older, experienced men and women were interviewed about their use of medicinal plants. A consensus analysis of medicinal plant use between the different populations was conducted. Results Across the different climatic regions a total of 57 species of plants were reported: 14 tree species, 10 shrub species, and 33 herb species. In the tropical and sub-tropical regions, Acacia catechu was the dominant tree while

Seepage through a hazardous-waste trench cover

Science.gov (United States)

Healy, R.W.

1989-01-01

Water movement through a waste-trench cover under natural conditions at a low-level radioactive waste disposal site in northwestern Illinois was studied from July 1982 to June 1984, using tensiometers, a moisture probe, and meteorological instruments. Four methods were used to estimate seepage: the Darcy, zero-flux plane, surface-based water-budget, and groundwater-based water-budget methods. Annual seepage estimates ranged from 48 to 216 mm (5-23% of total precipitation), with most seepage occurring in spring. The Darcy method, although limited in accuracy by uncertainty in hydraulic conductivity, was capable of discretizing seepage in space and time and indicated that seepage varied by almost an order of magnitude across the width of the trench. Lowest seepage rates occurred near the center of the cover, where seepage was gradual. Highest rates occurred along the edge of the cover, where seepage was highly episodic, with 84% of the total there being traced to wetting fronts from 28 individual storms. Limitations of the zero-flux-plane method were severe enough for the method to be judged inappropriate for use in this study.Water movement through a waste-trench cover under natural conditions at a low-level radioactive waste disposal site in northwestern Illinois was studied from July 1982 to June 1984, using tensiometers, a moisture probe, and meteorological instruments. Four methods were used to estimate seepage: the Darcy, zero-flux plane, surface-based water-budget, and groundwater-based water-budget methods. Annual seepage estimates ranged from 48 to 216mm (5-23% of total precipitation), with most seepage occurring in spring. The Darcy method, although limited in accuracy by uncertainty in hydraulic conductivity, was capable of discretizing seepage in space and time and indicated that seepage varied by almost an order of magnitude across the width of the trench. Lowest seepage rates occurred near the center of the cover, where seepage was gradual. Highest

Migration and Enrichment of Arsenic in the Rock-Soil-Crop Plant System in Areas Covered with Black Shale, Korea

Directory of Open Access Journals (Sweden)

Ji-Min Yi

2003-01-01

Full Text Available The Okchon black shale, which is part of the Guryongsan Formation or the Changri Formation of Cambro-Ordovician age in Korea provides a typical example of natural geological materials enriched with potentially toxic elements such as U, V, Mo, As, Se, Cd, and Zn. In this study, the Dukpyung and the Chubu areas were selected to investigate the migration and enrichment of As and other toxic elements in soils and crop plants in areas covered with black shale. Rock and soil samples digested in 4-acid solution (HCl+HNO3+HF+HClO4 were analyzed for As and other heavy metals by ICP-AES and ICP-MS, and plant samples by INAA. Mean concentration of As in Okchon black shale is higher than those of both world average values of shale and black shale. Especially high concentration of 23.2 mg As kg-1 is found in black shale from the Dukpyung area. Mean concentration of As is highly elevated in agricultural soils from the Dukpyung (28.2 mg kg-1 and the Chubu areas (32.6 mg kg-1. As is highly elevated in rice leaves from the Dukpyung (1.14 mg kg-1 and the Chubu areas (1.35 mg kg-1. The biological absorption coefficient (BAC of As in plant species decreases in the order of rice leaves > corn leaves > red pepper = soybean leaves = sesame leaves > corn stalks > corn grains. This indicates that leafy plants tend to accumulate As from soil to a greater degree than cereal products such as grains.

The importance of parameterization when simulating the hydrologic response of vegetative land-cover change

Science.gov (United States)

White, Jeremy; Stengel, Victoria; Rendon, Samuel; Banta, John

2017-08-01

Computer models of hydrologic systems are frequently used to investigate the hydrologic response of land-cover change. If the modeling results are used to inform resource-management decisions, then providing robust estimates of uncertainty in the simulated response is an important consideration. Here we examine the importance of parameterization, a necessarily subjective process, on uncertainty estimates of the simulated hydrologic response of land-cover change. Specifically, we applied the soil water assessment tool (SWAT) model to a 1.4 km2 watershed in southern Texas to investigate the simulated hydrologic response of brush management (the mechanical removal of woody plants), a discrete land-cover change. The watershed was instrumented before and after brush-management activities were undertaken, and estimates of precipitation, streamflow, and evapotranspiration (ET) are available; these data were used to condition and verify the model. The role of parameterization in brush-management simulation was evaluated by constructing two models, one with 12 adjustable parameters (reduced parameterization) and one with 1305 adjustable parameters (full parameterization). Both models were subjected to global sensitivity analysis as well as Monte Carlo and generalized likelihood uncertainty estimation (GLUE) conditioning to identify important model inputs and to estimate uncertainty in several quantities of interest related to brush management. Many realizations from both parameterizations were identified as behavioral in that they reproduce daily mean streamflow acceptably well according to Nash-Sutcliffe model efficiency coefficient, percent bias, and coefficient of determination. However, the total volumetric ET difference resulting from simulated brush management remains highly uncertain after conditioning to daily mean streamflow, indicating that streamflow data alone are not sufficient to inform the model inputs that influence the simulated outcomes of brush management

Dust pollution of snow cover in the industrial areas of Tomsk city (Western Siberia, Russia)

Science.gov (United States)

Talovskaya, A. V.; Filimonenko, E. A.; Osipova, N. A.; Yazikov, E. G.; Nadeina, L. V.

2016-03-01

This article describes the results of long-term monitoring (2007-2014) of snow cover pollution in the territory of Tomsk city. Snow samples were collected in the territory of Tomsk. Determination of dust load level was carried out by comparing with the background and reference values. It has been determined that the north-east and central parts of Tomsk are the most contaminated areas, where brickworks, coal and gas-fired thermal power plant are located. The analysis of long-term dynamics showed a dust load decrease in the vicinity of coal and gas-fired thermal power plant due to upgrading of the existing dust collecting systems. During the monitoring period the high dust load in the vicinity of brickworks did not change. The lowest value of the dust load on snow cover was detected in the vicinity of the petrochemical plant and concrete product plants. The near and far zones of dust load on snow cover were determined with the reference to the location of the studied plants.

29 CFR 776.27 - Construction which is related to covered production.

Science.gov (United States)

2010-07-01

... Construction Industry Individual Employee Coverage in the Construction Industry § 776.27 Construction which is... Construction work performed upon the plant and facilities of such a utility is covered as in the case of any... 29 Labor 3 2010-07-01 2010-07-01 false Construction which is related to covered production. 776.27...

Areal variability of the mineral soil cover in a reclaimed soda waste dumping site

Directory of Open Access Journals (Sweden)

Klatka Sławomir

2017-03-01

Full Text Available Areal variability of the mineral soil cover in a reclaimed soda waste dumping site. This paper provides an analysis of the areal variability of the thickness and selected physical and chemical properties of the mineral cover formed in the process of settling ponds reclamation at the former Krakow Soda Plant “Solvay”. The topsoil is intended to provide a substrate for plants, therefore, its quality is the main determinant of the development for herbaceous and woody vegetation. Areal variability of the topsoil parameters was determined by kriging. In the context of the envisaged direction of management of the settling ponds, the analysis showed that electrical conductivity, thickness of the soil cover and the sand fraction content have potentially the highest impact on the diversification of vegetation. Understanding the spatial variability of the soil cover parameters, that are essential for vegetation, may contribute to increasing the efficiency of biological reclamation and also to cost reduction. Precise selection of the areas unsuitable for plant growth makes it possible to improve soil parameters on limited areas similarly as in the precision agriculture.

Increasing diveristy of arbuscular mycorrhizal fungi in agroecosystems using specific cover crops

Science.gov (United States)

Fall-planted cover crops provide a plant host for obligate symbiotic arbuscular mycorrhizal fungi (AMF) during otherwise fallow periods and thus may increase AMF numbers in agroecosystems. Increased AMF numbers should increase mycorrhizal colonization of the subsequent cash crops, which has been li...

Phytochemical screening, total phenolic, total flavonoids contents and antioxidant activity of cinchona ledgeriana leaves ethanol extract

Science.gov (United States)

Sundowo, Andini; Artanti, Nina; Hanafi, M.; Minarti, Primahana, Gian

2017-11-01

C ledgeriana is a medicinal plant that contains alkaloids, especially on the barks for commercial production of quinine as antimalarial. The main alkaloids in this plant are cinchonine, cinchonidine, quinine and quinidine. Besides for antiamalarial this plant is also commonly used to treat whooping cough, influenza and dysentery. Compare to other medicinal plants, nowadays only very few studies were conducted in Cinchona species. Our current study aims to determine the content of phytochemical, total phenol and total flavonoids from C. ledgeriana leaves 70% ethanol extract. The extraction was performed by maceration method using 70% ethanol solvent and then fractionated into hexane, ethylacetate and butanol. Phytochemical screening was performed to determine the content of alkaloids, flavonoids, terpenoids, tannins and saponins. Total phenol and flavonoid contents of the extract were determined by Folin-Ciocalteu and alumunium chloride colorimetric methods using gallic acid and quercetin as standards. The antioxidant activity was determined by using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. The results of phytochemical screening showed that the 70% ethanol extract of C. ledgeriana leaves contained alkaloids, flavonoids, terpenoids, tannins and saponins. The total phenol and total flavonoids analysis showed that ethyl acetate fraction had the highest total phenol (40.23%) and total flavonoids (65.34%).

Meeting summary of the second CSNI specialist meeting on simulators and plant analyzers - Current Issues in Nuclear Power Plant Simulation

International Nuclear Information System (INIS)

1998-01-01

The Second CSNI Specialist Meeting on Simulators and Plant Analyzers: Current Issues in Nuclear Power Plant Simulation was held in Espoo, Finland, from September 29 through October 2, 1997. It was organised by CSNI Principal Working Group on Coolant System Behaviour (PWG2), Task Group on Thermal Hydraulic Applications (TG-THA), in co-operation with Technical Research Centre of Finland. The meeting in Espoo attracted some 90 participants from 17 countries. A total of 49 invited papers were presented in the meeting in addition to 7 simulator system demonstrations. Ample time was reserved for the presentations and informal discussions during the four meeting days. The previous meeting held in Lappeenranta, Finland, in 1992 collected some 85 participants from 12 countries, presenting a total of 40 papers. The meeting was structured into 6 sessions covering the important aspects of development and use of simulators and plant analyzers: Session I: New objectives, Requirements and Concepts. This session covered the progress experienced since the 1. simulator meeting and tried to address the changing role of simulators based on the changes in users' needs and developing possibilities. Session II: Trends in Simulation Technology. This session was reserved for studying the current trends in the simulation technology: software environments, visualisation, simulator configuration tools, programming languages and computer systems. Session III: Training and human factor studies using simulators. This session was created for studying the status of different uses of simulators such as educational simulators, human factor studies and integrated safety assessment in addition to traditional training. Regarding to the severe accidents, a question was raised whether the simulator use should be for training or education. Session IV: Modelling techniques. The session on modelling techniques was included to cover recent developments in the modelling techniques applicable to training

Determination Total Phosphour of Maize Plant Samples by Continuous Flow Analyzer in Comparison with Vanadium Molybdate Yellow Colorimetric Method

Directory of Open Access Journals (Sweden)

LIU Yun-xia

2015-12-01

Full Text Available The vanadium molybdate yellow colorimetric method(VMYC method is regarded as one of conventional methods for determining total phosphorus(P in plants, but it is time consuming procedure. Continuous flow analyzer(CFA is a fluid stream segmentation technique with air segments. It is used to measure P concentration based on the molybdate-antimony-ascorbic acid method of Murphy and Riley. Sixty nine of maize plant samples were selected and digested with H2SO4-H2O2. P concentrations in the digests were determined by CFA and VMYC method, respectively. The t test found that there was no any significant difference of the plant P contents measured by the CFA and the VMYC method. A linear equation could best describe their relationship: Y(CFA-P=0.927X(VMYC-P-0.002. The Pearson's correlation coefficient was 0.985 with a significance level(n=69, P<0.01. The CFA method for plant P measurement had a high precision with relative standard deviation(RSD less than 1.5%. It is suggested that the CFA based on Murphy and Riley colorimetric detection can be used to determinate total plant P in the digests solutions with H2SO4-H2O2. The CFA method is labor saving and can handle large numbers of samples. The human error in mixing with other operations is reduced to a great extent.

Land-cover effects on soil organic carbon stocks in a European city.

Science.gov (United States)

Edmondson, Jill L; Davies, Zoe G; McCormack, Sarah A; Gaston, Kevin J; Leake, Jonathan R

2014-02-15

Soil is the vital foundation of terrestrial ecosystems storing water, nutrients, and almost three-quarters of the organic carbon stocks of the Earth's biomes. Soil organic carbon (SOC) stocks vary with land-cover and land-use change, with significant losses occurring through disturbance and cultivation. Although urbanisation is a growing contributor to land-use change globally, the effects of urban land-cover types on SOC stocks have not been studied for densely built cities. Additionally, there is a need to resolve the direction and extent to which greenspace management such as tree planting impacts on SOC concentrations. Here, we analyse the effect of land-cover (herbaceous, shrub or tree cover), on SOC stocks in domestic gardens and non-domestic greenspaces across a typical mid-sized U.K. city (Leicester, 73 km(2), 56% greenspace), and map citywide distribution of this ecosystem service. SOC was measured in topsoil and compared to surrounding extra-urban agricultural land. Average SOC storage in the city's greenspace was 9.9 kg m(-2), to 21 cm depth. SOC concentrations under trees and shrubs in domestic gardens were greater than all other land-covers, with total median storage of 13.5 kg m(-2) to 21 cm depth, more than 3 kg m(-2) greater than any other land-cover class in domestic and non-domestic greenspace and 5 kg m(-2) greater than in arable land. Land-cover did not significantly affect SOC concentrations in non-domestic greenspace, but values beneath trees were higher than under both pasture and arable land, whereas concentrations under shrub and herbaceous land-covers were only higher than arable fields. We conclude that although differences in greenspace management affect SOC stocks, trees only marginally increase these stocks in non-domestic greenspaces, but may enhance them in domestic gardens, and greenspace topsoils hold substantial SOC stores that require protection from further expansion of artificial surfaces e.g. patios and driveways. Copyright �

Are post-fire silvicultural treatments a useful tool to fight the climate change threat in terms of plant diversity?

Science.gov (United States)

Hedo de Santiago, Javier; Esteban Lucasr Borja, Manuel; de las Heras, Jorge

2016-04-01

Adaptative forest management demands a huge scientific knowledge about post-fire vegetation dynamics, taking into account the current context of global change. We hypothesized that management practices should be carry out taking into account the climate change effect, to obtain better results in the biodiversity maintenance across time. All of this with respect to diversity and species composition of the post-fire naturally regenerated Aleppo pine forests understory. The study was carried out in two post-fire naturally regenerated Aleppo pine forests in the Southeastern of the Iberian Peninsula, under contrasting climatic conditions: Yeste (Albacete) shows a dry climate and Calasparra (Murcia) shows a semiarid climate. Thinning as post-fire silvicultural treatment was carried out five years after the wildfire event, in the year 1999. An experiment of artificial drought was designed to evacuate 15% of the natural rainfall in both sites, Yeste and Calasparra, to simulate climate change. Taking into account all the variables (site, silvicultural treatment and artificial drought), alpha diversity indices including species richness, Shannon and Simpson diversity indices, and plant cover, were analyzed as a measure of vegetation abundance. The results showed that plant species were affected by thinning, whereas induced drought affected total cover and species, with lower values at Yeste. Significant site variation was also observed in soil properties, species richness and total plant cover, conversely to the plant species diversity indices. We conclude that the plant community shows different responses to a simulated environment of climate change depending on the experimental site.

Foliar uptake of nitrogen from ant fecal droplets: an overlooked service to ant plants

DEFF Research Database (Denmark)

Pinkalski, Christian Alexander Stidsen; Jensen, Karl-Martin Vagn; Damgaard, Christian Frølund

2018-01-01

and subsequently deposited fecal droplets on the seedlings, coffee leaves showed increased levels of 15N and total N compared to control plants without ants. This was evident for both exposed leaves and leaves covered in plastic bags (i.e. not directly exposed to ants). Thus, N from ant excretions was absorbed...

Production of marine plant biomass: Management, cultivation, and genetic modification of macrophytic algae

Science.gov (United States)

Vandermeer, J. P.

1982-12-01

Every second of every day, the Sun's fusion reactions convert thousands of tons of hydrogen into helium with the release of almost unimaginable amounts of energy. Through the photosynthetic activity of plants, both aquatic and terrestrial, a small fraction of this energy is trapped and stored as plant biomass. The oceans cover a greater fraction of the globe than do the land masses, making it appropriate to consider their contribution to the total biomass production, and their potential as a source of raw materials for the extraction of chemicals and fuels. A rather broad synthesis, convering the total seaweed resource and some of the constraints placed on harvesting these plants, attempts to farm the oceans to increase the supply of desirable species, attempts to cultivate seaweeds in enclosures where environmental parameters are controlled, and finally, the limited amount of genetic manipulation that was applied to these plants was presented. Only the larger red and brown seaweeds were considered because they represent the bulk of the biomass.

DESIGN, PERFORMANCE, AND SUSTAINABILITY OF ENGINEERED COVERS FOR URANIUM MILL TAILINGS

Energy Technology Data Exchange (ETDEWEB)

Waugh, W. Jody

2004-04-21

Final remedies at most uranium mill tailings sites include engineered covers designed to contain metals and radionuclides in the subsurface for hundreds of years. Early cover designs rely on compacted soil layers to limit water infiltration and release of radon, but some of these covers inadvertently created habitats for deep-rooted plants. Root intrusion and soil development increased the saturated hydraulic conductivity several orders of magnitude above design targets. These covers may require high levels of maintenance to sustain long-term performance. Relatively low precipitation, high potential evapotranspiration, and thick unsaturated soils favor long-term hydrologic isolation of buried waste at arid and semiarid sites. Later covers were designed to mimic this natural soil-water balance with the goal of sustaining performance with little or no maintenance. For example, the cover for the Monticello, Utah, Superfund site relies on a thick soil-sponge layer overlying a sand-and-gravel capillary barrier to store precipitation while plants are dormant and on native vegetation to dry the soil sponge during the growing season. Measurements of both off-site caisson lysimeters and a large 3-ha lysimeter built into the final cover show that drainage has been well below a U.S. Environmental Protection Agency target of less than 3.0 mm/yr. Our stewardship strategy combines monitoring precursors to failure, probabilistic riskbased modeling, and characterization of natural analogs to project performance of covers for a range of possible future environmental scenarios. Natural analogs are needed to understand how ecological processes will influence cover performance, processes that cannot be predicted with short-term monitoring and existing numerical models.

Natural analogs of the long-term performance of engineered covers

International Nuclear Information System (INIS)

Waugh, W.J.; Petersen, K.L.; Link, S.O.; Bjornstad, B.N.; Gee, G.W.

1994-01-01

The unprecedented legislative demand that in-situ waste-disposal facilities effectively persist indefinitely requires a performance assessment approach that exceeds standard engineering practices and incorporates possible long-term changes in site hydrology, geology, and ecology. Even in relatively arid regions, over time, buried waste will be vulnerable to transport via rainwater percolation, gas diffusion, erosion, and intrusion by plant roots, burrowing animals, and humans. Standard models and field tests of engineered covers designed to impede these pathways implicitly and erroneously assume that initial conditions of many key determinants will persist indefinitely. Evidence from natural, archaeological, and engineered analogs is needed (1) to identify and understand emergent system attributes that cannot be captured with computer models or short-term experiments, and (2) to develop modeling and field tests that reasonably bound possible future changes in waste-site environments. Analogs of local responses to future global climate change exist as proxy ecological and archaeological records of similar paleoclimates. Future pedogenic influences can be inferred form measurements of key soil properties in natural and archaeological soil profiles analogous to engineered covers. Many cover designs depend on water extraction by plants. Influences of vegetation change can be inferred by measuring water extraction parameters in plant communities representing successional chronosequences. Habitats similar to those created on waste sites provide evidence of the potential for biological intrusion. Recent and ancient man-made structures provide evidence of the future stability of waste-site covers and of features that may discourage human intrusion. 108 refs., 4 figs

Fiscal year 1993 well plugging and abandonment program, Y-12 Plant, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

1993-09-01

This report is a synopsis of the progress of the well plugging and abandonment program at the Y-12 Plant, Oak Ridge, Tennessee, from December 1992 through August 20, 1993. A total of 70 wells and borings were plugged and abandoned during the period of time covered in this report. All wells and borings were plugged and abandoned in accordance with the Monitoring Well Plugging and Abandonment Plan for the US Department of Energy, Y-12 Plant, Oak Ridge, Tennessee (HSW, Inc. 1991).

Solar thermal power plants

International Nuclear Information System (INIS)

Schnatbaum, L.

2009-01-01

The solar thermal power plant technology, the opportunities it presents and the developments in the market are outlined. The focus is on the technology of parabolic trough power plants, a proven technology for solar power generation on a large scale. In a parabolic trough power plant, trough-shaped mirrors concentrate the solar irradiation onto a pipe in the focal line of the collector. The thermal energy thus generated is used for electricity generation in a steam turbine. Parabolic trough plants can be combined with thermal storage and fossil or biomass fired heat exchangers to generate electricity even when the sun is not shining. Solar Millennium AG in Erlangen has developed the first power plant of this kind in Europe. After two years of construction the plant started operation in Southern Spain in 2008. This one and its sister projects are important steps leading the way for the whole market. The paper also covers the technological challenges, the key components used and the research and development activities concerning this technology. Solar thermal power plants are ideal for covering peak and medium loads in power grids. In hybrid operation they can also cover base-load. The Solar Chimney power plant, another striking technology for the conversion of solar into electric energy, is described briefly. The paper concludes with a look at the future - the import of solar energy from the deserts of North Africa to central Europe. (author)

Assessing winter cover crop nutrient uptake efficiency using a water quality simulation model

OpenAIRE

Yeo, I.-Y.; Lee, S.; Sadeghi, A. M.; Beeson, P. C.; Hively, W. D.; McCarty, G. W.; Lang, M. W.

2014-01-01

Winter cover crops are an effective conservation management practice with potential to improve water quality. Throughout the Chesapeake Bay watershed (CBW), which is located in the mid-Atlantic US, winter cover crop use has been emphasized, and federal and state cost-share programs are available to farmers to subsidize the cost of cover crop establishment. The objective of this study was to assess the long-term effect of planting winter cover crops to improve water quality a...

12种林下地被植物水土保持功能研究%Soil and Water Conservation of Twelve Under-forest Cover Plants

Institute of Scientific and Technical Information of China (English)

赵雪乔; 袁小环

2017-01-01

To study the soil and water conservation function of cover plants on the forest floor,the water absorption of stem and leaves,the soil anti-erodibility and the soil permeability were measured with 12 cover plants using the indoor leaf immersion method,the hydrostatic collapse method,and the bicyclic knife method,respectively.The results showed that Calamagrostis brachytricha and Phalaris arundinacea var.picta had the highest water absorption over 40％ of the stem and leaves weight;Phalaris arundinacea var.Picta,Carex lanceolata and Carex leucochlora best increased the soil anti-erodibility;the cover plants decreased the soil bulk density and generally increased the soil permeability,and the permeability of soils planted with Phalaris arundinacea var.picta,Pennisetum alopecuroides,C.brachytricha,C.leucochlora,C.lanceolata and Cosmos sulphureus extremely significantly differed from the control.Therefore,C.leucochlora,C.Lanceolata,P.arundinacea var.picta and C.brachytricha have the higher integrated soil and water conservation function and fit to be planted under the forest.%为了研究林下地被植物的水土保持功能,分别运用室内茎叶浸泡法、静水崩析法、双环刀法对12种地被植物的茎叶截留雨水能力、土壤抗蚀性和渗透性进行了测定.结果表明:茎叶截留雨水最强的为拂子茅(Calamagrostis brach ytricha)和玉带草(Phalaris arundinacea var.picta),超过自身质量的40％;玉带草、披针叶苔草(Carex lanceolata)和青绿苔草(Carex leucochlora)最大地提高了土壤抗蚀性;种植地被植物普遍地降低了土壤容重,提高了土壤的渗透系数,其中玉带草、狼尾草(Pennisetum alopecuroides)、拂子茅、青绿苔草、披针叶苔草、硫华菊效果极显著.青绿苔草、披针叶苔草、玉带草、拂子茅的综合水土保持功能较强,适合林下栽植.

Investigation of ratio 'strontium-calcium' in the plants and in the corresponding soil solution for 90Sr and for natural total strontium

International Nuclear Information System (INIS)

Prorok, V.V.; Makarenko, T.Yi.; Mel'nichenko, L.Yu.; Mason, K.F.V.; Ganushevich, A.P.; Ostashko, V.V.

2005-01-01

Ratios Sr/Ca for natural total strontium and 90 Sr/Ca in the plants and in the corresponding soil solutions for three experimental lands with 'fuel' type of pollution for several plants at natural conditions are determined. The lands with tree different types of soil are at the Exclusive Zone of the Chernobyl Power Station. The obtained experimental results shown that ratio Sr/Ca in plant is equal to this ratio in the corresponding soil solution for all investigated lands and plants. Ratio 90 Sr/Ca in plant exceeds this ratio at the corresponding soil solution

Assessing plant community composition fails to capture impacts of white-tailed deer on native and invasive plant species.

Science.gov (United States)

Nuzzo, Victoria; Dávalos, Andrea; Blossey, Bernd

2017-07-01

Excessive herbivory can have transformative effects on forest understory vegetation, converting diverse communities into depauperate ones, often with increased abundance of non-native plants. White-tailed deer are a problematic herbivore throughout much of eastern North America and alter forest understory community structure. Reducing (by culling) or eliminating (by fencing) deer herbivory is expected to return understory vegetation to a previously diverse condition. We examined this assumption from 1992 to 2006 at Fermilab (Batavia, IL) where a cull reduced white-tailed deer ( Odocoileus virginianus ) abundance in 1998/1999 by 90 % from 24.6 to 2.5/km 2 , and at West Point, NY, where we assessed interactive effects of deer, earthworms, and invasive plants using 30 × 30 m paired fenced and open plots in 12 different forests from 2009 to 2012. We recorded not only plant community responses (species presence and cover) within 1 m 2 quadrats, but also responses of select individual species (growth, reproduction). At Fermilab, introduced Alliaria petiolata abundance initially increased as deer density increased, but then declined after deer reduction. The understory community responded to the deer cull by increased cover, species richness and height, and community composition changed but was dominated by early successional native forbs. At West Point plant community composition was affected by introduced earthworm density but not deer exclusion. Native plant cover increased and non-native plant cover decreased in fenced plots, thus keeping overall plant cover similar. At both sites native forb cover increased in response to deer reduction, but the anticipated response of understory vegetation failed to materialize at the community level. Deer-favoured forbs ( Eurybia divaricata , Maianthemum racemosum , Polygonatum pubescens and Trillium recurvatum ) grew taller and flowering probability increased in the absence of deer. Plant community monitoring fails to capture

Medicinal Plants in the Flora of Luhansk Region

Directory of Open Access Journals (Sweden)

S.Yu. Naumov

2016-11-01

Full Text Available To establish a resource base of medicinal plants of Donbass, and to develop methods for their balanced use, it is necessary to conduct an inventory and analysis of the spread of wild species, that recently was not carried out in Luhansk and Donetsk region. These circumstances have served as an incentive to carry out special investigations. Test species belong to 403 genus and 108 families. List of vascular plants of Luhansk region has more than 1,200 species. We have established that in the study area, there are 718 species of medicinal plants, representing 60 % of the total flora of the region, covering so much of the taxonomic diversity of Donbass flora. The family of the Asteraceae (105 species, 50 genuses is different in terms of the greatest number of species of medicinal plants and genus family. The families of Brassicaceae, Fabaceae, Apiaceae, Lamiaceae and Poaceae contain more than 40 species, the families of Apiaceae и Rosaceae — over 30 species, Caryophylaceae и Polygonaceae — more than 20 species, a total of 301 species. The remaining 99 families presented a small number of basic taxonomic units. The species Viscum album, Ajuga chia, Salvia nemorosa were found during expeditions. These species have not been previously described for the region.

FY 1983 annual report on the research and development of automatic sewing systems. Total systems; 1983 nendo jido hosei system no kenkyu kaihatsu seika hokokusho. Total system

Energy Technology Data Exchange (ETDEWEB)

NONE

1984-03-01

The automatic sewing system technique research association has been commissioned by the Agency of Industrial Science and Technology for (research and development of automatic sewing systems). This program covers R and D of the elementary techniques for total systems and sewing preparation/processing, sewing/assembling, cloth handling, and system management/control. This report describes the results of the R and D efforts for the total systems. The basic data are collected for a total of 5 representative types of apparels. The technical problems involved in the current and automatic sewing systems are clarified for each apparel type, to collect the data for studying the test plant plans. The automatic sewing system for each apparel type is illustrated by images, for expressing the system concepts. The concept for the basic designs of the total system is drawn for FMS. For achieving the objective of reducing time for producing unit quantity of diversified types of clothes in small quantities at least by 50% from the current level, the study is focused on how the works are (flown) in the system, for which configuration of each device is studied. The basic specifications are drawn, viewed from development of the total system. (NEDO)

Effect of Different Tillage Methods and Cover Crop Types on Yield and Yield Components of Wheat

Directory of Open Access Journals (Sweden)

Z Sharefee

2018-05-01

treatments were applied, seedbed preparation was carried out and wheat Anfarm- 4 (Bam was planted. At the end of the growing season, yield and yield components of wheat were measured. Results and Discussion The results indicated that the maximum grain yield, biological yield, and spike.m-2 of wheat were observed with the no-till and reduced tillage treatments. The wheat spike weight significantly increased in the treatment of no-tillage compared with conventional tillage treatment. It seems that increased crop yield under no-till and reduced till systems might be owing to the enhancement of the soil nutrient status, reduced weed populations, improved physical health of the soil improved soil water status and increased efficiency of nutrient usage in these systems comparing with the conventional tillage systems. The main effect of cover crop type showed that incorporating chickling pea and rocket salad resulted in the greatest grain yield, thousand-kernal weight, spike weight, and biological yield of wheat compared to the control (no cover crop and also chickling pea, rocket salad and barley caused the greatest grain. Spike-1 of wheat compared to the control (no cover crop. Although the use of total cover crops improved yield and yield components in wheat. Chickling pea superiority in many traits was evident in comparison with other cover crops. This superiority could be due to the fact that this plant belongs to the legume family and legumes release higher amounts of nitrogen during decomposition compared to grass species. Grasses produce large amounts of carbon and are slowly decomposed. Although rocket salad does not belong to the legume family, due to having deep roots, it is able to absorb nutrients from the deep soil layers and provide the main plant with these nutrients after its decay. Conclusions The results of this study revealed that employment of conservation tillage systems remarkably affected the yield and yield components of wheat, and the greatest positive

Nutrient addition shifts plant community composition towards earlier flowering species in some prairie ecoregions in the U.S. Central Plains.

Directory of Open Access Journals (Sweden)

Lori Biederman

Full Text Available The distribution of flowering across the growing season is governed by each species' evolutionary history and climatic variability. However, global change factors, such as eutrophication and invasion, can alter plant community composition and thus change the distribution of flowering across the growing season. We examined three ecoregions (tall-, mixed, and short-grass prairie across the U.S. Central Plains to determine how nutrient (nitrogen (N, phosphorus, and potassium (+micronutrient addition alters the temporal patterns of plant flowering traits. We calculated total community flowering potential (FP by distributing peak-season plant cover values across the growing season, allocating each species' cover to only those months in which it typically flowers. We also generated separate FP profiles for exotic and native species and functional group. We compared the ability of the added nutrients to shift the distribution of these FP profiles (total and sub-groups across the growing season. In all ecoregions, N increased the relative cover of both exotic species and C3 graminoids that flower in May through August. The cover of C4 graminoids decreased with added N, but the response varied by ecoregion and month. However, these functional changes only aggregated to shift the entire community's FP profile in the tall-grass prairie, where the relative cover of plants expected to flower in May and June increased and those that flower in September and October decreased with added N. The relatively low native cover in May and June may leave this ecoregion vulnerable to disturbance-induced invasion by exotic species that occupy this temporal niche. There was no change in the FP profile of the mixed and short-grass prairies with N addition as increased abundance of exotic species and C3 graminoids replaced other species that flower at the same time. In these communities a disturbance other than nutrient addition may be required to disrupt phenological

Sediment yield control in vineyards covered with cereal. Effect of tillage

International Nuclear Information System (INIS)

Ruiz-Colmenero, M.; Bienes, R.; Marques, M. J.

2009-01-01

A study has been carried out about the use of plant cover treatment to avoid land degradation in a hillside rainfed vineyard in Madrid under Mediterranean semiarid climate. Three treatments were tested: traditional tillage (lab) soil covered by Brachypodium distrachyon (bra) with self-sowing, soil covered by Scale cereale (sec) mown in Spring. Three erosion plots per treatment were placed in the middle of the strips and 2 simulated rainfalls were carried out at each plot in autumn, before and after the tillage. (Author) 7 refs.

Evaluation of construction cost of pyro-partitioning plant

International Nuclear Information System (INIS)

Kinoshita, Kensuke; Kurata, Masateru; Inoue, Tadashi

1999-01-01

This study was conducted to evaluate the construction cost of a pyro-partitioning plant. The plant capacity was chosen to accommodate processing of the HLLW generated by PUREX reprocessing of 800 ton of spent LWR fuel. The block flow diagram and mass balance obtained from our previous experimental data were used to produce a detailed process-flow diagram and to design the plant. In this evaluation, the plant was estimated to cover an area of about 90 m x 70 m, and to cost $576 million for construction. This study shows that the cost of process equipments, such as reaction vessels, accountability tanks and so on, is just about 13% of total construction cost. On the other hand, the cost of process robots and the equipments for key measurement point (KMP) is major part in the cost of in-cell equipment. So it is clear that the construction cost can be reduced by reducing the number of material balance area (MBA) and KMP. (author)

HVAC systems and nuclear plant safety. Final report, May 1992

International Nuclear Information System (INIS)

1992-05-01

The primary objective of this study was to provide perspective on the overall risk impact of heating, ventilating, and air conditioning (HVAC) system problems. Industry experience with HVAC system problems is documented and analyzed. In addition, the results of 10 plant-specific probabilistic risk assessments (PRA) were reviewed to determine the contribution of HVAC systems to the risk of core damage. The PRAs included in this review cover a broad range of plant types and operating conditions. The review found that the impact of HVAC systems on risk is plant specific. These results exhibit a broad range of frequencies for HVAC contribution to risk, and the percentage of total core damage due to HVAC problems also had a wide variability. Plant-specific differences in design, environment, operation, and maintenance are the primary factors in determining the risk contribution of HVAC systems. (author)

Influence of cover crop treatments on the performance of a vineyard in a humid region

Energy Technology Data Exchange (ETDEWEB)

Trigo-Córdoba, E.; Bouzas-Cid, Y.; Orriols-Fernández, I.; Díaz-Losada, E.; Mirás-Avalos, J.M.

2015-07-01

Vineyards are usually managed by tilling the inter-rows to avoid competition from other plants for soil water and nutrients. However, in humid and sub-humid climates, such as that of NW Spain, cover crops may be an advantage for controlling vine vegetative growth and improving berry composition, while reducing management costs. The current study was conducted over three consecutive growing seasons (2012-2014) to assess the effects of establishing three permanent cover crop treatments on water relations, vine physiology, yield and berry composition of a vineyard of the red cultivar ‘Mencía’ (Vitis vinifera L.) located in Leiro, Ourense. Treatments consisted of four different soil management systems: ST, soil tillage; NV, native vegetation; ER, English ryegrass (Lolium perenne L.); and SC, subterranean clover (Trifolium subterraneum L.). Midday stem water potential was more negative in the native vegetation treatment, causing significant reductions in leaf stomatal conductance on certain dates. Total vine leaf area and pruning weight was reduced in the cover crop treatments in the last year of the experiment. Yield was unaffected by the presence of a cover crop. No significant differences among treatments were observed for berry composition; however, wines were positively affected by the SC treatment (higher tannin content and colour intensity and lower malic acid concentration when compared with ST). Wines from the cover crop treatments were preferred by taste panelists. These results indicate that in humid climates cover crop treatments can be useful for reducing vine vegetative growth without compromising yield and berry quality. (Author)

Nitrous Oxide Production at a Fully Covered Wastewater Treatment Plant: Results of a Long-Term Online Monitoring Campaign.

Science.gov (United States)

Kosonen, Heta; Heinonen, Mari; Mikola, Anna; Haimi, Henri; Mulas, Michela; Corona, Francesco; Vahala, Riku

2016-06-07

The nitrous oxide emissions of the Viikinmäki wastewater treatment plant were measured in a 12 month online monitoring campaign. The measurements, which were conducted with a continuous gas analyzer, covered all of the unit operations of the advanced wastewater-treatment process. The relation between the nitrous oxide emissions and certain process parameters, such as the wastewater temperature, influent biological oxygen demand, and ammonium nitrogen load, was investigated by applying online data obtained from the process-control system at 1 min intervals. Although seasonal variations in the measured nitrous oxide emissions were remarkable, the measurement data indicated no clear relationship between these emissions and seasonal changes in the wastewater temperature. The diurnal variations of the nitrous oxide emissions did, however, strongly correlate with the alternation of the influent biological oxygen demand and ammonium nitrogen load to the aerated zones of the activated sludge process. Overall, the annual nitrous oxide emissions of 168 g/PE/year and the emission factor of 1.9% of the influent nitrogen load are in the high range of values reported in the literature but in very good agreement with the results of other long-term online monitoring campaigns implemented at full-scale wastewater-treatment plants.

Chromium in soil layers and plants on closed landfill site after landfill leachate application.

Science.gov (United States)

Zupancic, Marija; Justin, Maja Zupancic; Bukovec, Peter; Selih, Vid Simon

2009-06-01

Landfill leachate (LL) usually contains low concentrations of heavy metals due to the anaerobic conditions in the methanogenic landfill body after degradation of easily degradable organic matter and the neutral pH of LL, which prevents mobilization and leaching of metals. Low average concentrations of metals were also confirmed in our extensive study on the rehabilitation of an old landfill site with vegetative landfill cover and LL recirculation after its treatment in constructed wetland. The only exception was chromium (Cr). Its concentrations in LL ranged between 0.10 and 2.75 mg/L, and were higher than the concentrations usually found in the literature. The objectives of the study were: (1) to understand why Cr is high in LL and (2) to understand the fate and transport of Cr in soil and vegetation of landfill cover due to known Cr toxicity to plants. The total concentration of Cr in LL, total and exchangeable concentrations of Cr in landfill soil cover and Cr content in the plant material were extensively monitored from May 2004 to September 2006. By obtained data on Cr concentration in different landfill constituents, supported with the data on the amount of loaded leachate, amount of precipitation and potential evapotranspiration (ETP) during the performance of the research, a detailed picture of time distribution and co-dependency of Cr is provided in this research. A highly positive correlation was found between concentrations of Cr and dissolved organic carbon (r=0.875) in LL, which indicates the co-transport of Cr and dissolved organic carbon through the system. Monitoring results showed that the substrate used in the experiment did not contribute to Cr accumulation in the landfill soil cover, resulting in percolation of a high proportion of Cr back into the waste layers and its circulation in the system. No negative effects on plant growth appeared during the monitoring period. Due to low uptake of Cr by plants (0.10-0.15 mg/kg in leaves and 0.05-0.07 mg

Quantifying Structural and Compositional Changes in Forest Cover in NW Yunnan, China

Science.gov (United States)

Hakkenberg, C.

2012-12-01

NW Yunnan, China is a region renowned for high levels of biodiversity, endemism and genetically distinct refugial plant populations. It is also a focal area for China's national reforestation efforts like the Natural Forest Protection Program (NFPP), intended to control erosion in the Upper Yangtze watershed. As part of a larger project to investigate the role of reforestation programs in facilitating the emergence of increasingly species-rich forest communities on a previously degraded and depauperate land mosaic in montane SW China, this study uses a series of Landsat TM images to quantify the spatial pattern and rate of structural and compositional change in forests recovering from medium to large-scale disturbances in the area over the past 25 years. Beyond the fundamental need to assess the outcomes of one of the world's largest reforestation programs, this research offers approaches to confronting two critical methodological issues: (1) techniques for characterizing subtle changes in the nature of vegetation cover, and (2) reducing change detection uncertainty due to persistent cloud cover and shadow. To address difficulties in accurately assessing the structure and composition of vegetative regrowth, a biophysical model was parameterized with over 300 ground-truthed canopy cover assessment points to determine pattern and rate of long-term vegetation changes. To combat pervasive shadow and cloud cover, an interactive generalized additive model (GAM) model based on topographic and spatial predictors was used to overcome some of the constraints of satellite image analysis in Himalayan regions characterized by extreme topography and extensive cloud cover during the summer monsoon. The change detection is assessed for accuracy using ground-truthed observations in a variety of forest cover types and topographic positions. Results indicate effectiveness in reducing the areal extent of unclassified regions and increasing total change detection accuracy. In addition

Fiscal year 1996 well plugging and abandonment program Y-12 Plant, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-04-01

This report is a synopsis of the progress of the well plugging and abandonment program at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee, from August 1995 through August 1996. A total of 27 wells, piezometers, and borings were plugged and abandoned during the period of time covered in this report. All wells and borings were plugged and abandoned in accordance with the Monitoring Well Plugging and Abandonment Plan for the U.S. Department of Energy, Y-12 Plant, Oak Ridge, Tennessee (HSW, Inc. 1991).

Rubber and Land-Cover Land-Use Change in Mainland Southeast Asia

Science.gov (United States)

Fox, J. M.; Hurni, K.

2017-12-01

Over the past half century, the five countries of Mainland Southeast Asia (MSEA) - Cambodia, Laos, Myanmar, Thailand, and Vietnam - have witnessed major shifts from predominantly subsistence agrarian economies to increasingly commercialized agriculture. Major drivers of change include policy initiatives that fostered regional economic integration and promoted among other changes rapid expansion of boom-crop plantations. Among the many types of commercial boom crops promoted and grown in MSEA are numerous tree-based products such as rubber, coffee, tree species for pulp and paper (particularly eucalyptus and acacia), cashews, and fruits such as oranges, lychees, and longans. The project proposal hypothesized that most (but not all) tree crops replaced swidden cultivation fields and hence are not necessarily accompanied by deforestation. We used MODIS EVI and SWIR time-series from 2001-2014 to classify changes in tree cover across MSEA; a total of 6849 sample points were used to train the classifier (75%) and verification (25%). The classification consists of 24 classes and 17 classes represent tree crops. Project results suggest that 4.4 m ha of rubber have been planted since 2003; 50% of rubber is planted on former evergreen forest land, 18% on deciduous forest land, and 32% on low vegetation area (former crop lands, bushes, scrub). Tree crops occupy about 8% of the landscape (half of that is rubber). Due to the differences in their political and economic histories these countries display different LCLUCs. In northern Laos, smallholder rubber plantations dominate and shifting cultivation is common in the upland. In southern Laos, large-scale plantations of rubber, coffee, eucalyptus, and sugarcane are widespread. In Thailand, vast areas are covered by annual agriculture; fruit trees and rubber are the prevailing tree crops and are mostly planted by smallholders. In Cambodia, large-scale rubber plantations have expanded in recent years on forest lands; smallholder

Direct effects of warming increase woody plant abundance in a subarctic wetland.

Science.gov (United States)

Carlson, Lindsay G; Beard, Karen H; Adler, Peter B

2018-03-01

Both the direct effects of warming on a species' vital rates and indirect effects of warming caused by interactions with neighboring species can influence plant populations. Furthermore, herbivory mediates the effects of warming on plant community composition in many systems. Thus, determining the importance of direct and indirect effects of warming, while considering the role of herbivory, can help predict long-term plant community dynamics. We conducted a field experiment in the coastal wetlands of western Alaska to investigate how warming and herbivory influence the interactions and abundances of two common plant species, a sedge, Carex ramenskii , and a dwarf shrub, Salix ovalifolia . We used results from the experiment to model the equilibrium abundances of the species under different warming and grazing scenarios and to determine the contribution of direct and indirect effects to predict population changes. Consistent with the current composition of the landscape, model predictions suggest that Carex is more abundant than Salix under ambient temperatures with grazing (53% and 27% cover, respectively). However, with warming and grazing, Salix becomes more abundant than Carex (57% and 41% cover, respectively), reflecting both a negative response of Carex and a positive response of Salix to warming. While grazing reduced the cover of both species, herbivory did not prevent a shift in dominance from sedges to the dwarf shrub. Direct effects of climate change explained about 97% of the total predicted change in species cover, whereas indirect effects explained only 3% of the predicted change. Thus, indirect effects, mediated by interactions between Carex and Salix, were negligible, likely due to use of different niches and weak interspecific interactions. Results suggest that a 2°C increase could cause a shift in dominance from sedges to woody plants on the coast of western Alaska over decadal timescales, and this shift was largely a result of the direct effects

Use of different surface covering materials to enhance removal of radiocaesium in plants and upper soil from orchards in Fukushima prefecture.

Science.gov (United States)

Sato, Mamoru; Akai, Hiroko; Saito, Yuichi; Takase, Tsugiko; Kikunaga, Hidetoshi; Sekiya, Nobuhito; Ohtsuki, Tsutomu; Yamaguchi, Katsuhiko

2017-04-04

The effectiveness of a decontamination methodology whereby herbaceous plants were grown through different materials covering the soil surface followed by subsequent removal of the material, associated plant tissues and attached soil on 137 Cs removal from soil was evaluated. Revegetation netting sown with Kentucky bluegrass and white clover had a high effectiveness in 137 Cs removal when rolling up the plants, roots, and rhizosphere soil approximately 6 months after sowing. The removal rate was lower when there was higher 137 Cs vertical migration down the soil profile. The maximum removal effectiveness of 93.1% was observed by rolling up fertilized Kentucky bluegrass with a well-developed root mat without netting, indicating that applying nutrients to encourage the development of roots or root mats in the 3 cm topsoil rhizosphere is an efficient technology to increase the decontamination effect of plant removal in orchards. Netting and weeding were able to remove up to 80% of 137 Cs in the soil without the use of heavy machinery. There was a significant relationship between the removal ratio and the removed soil weight per area. Using the relationship on the site below the canopy, removal of 14.3 kg m -2 DW soil would achieve a removal ratio of 80%. The effectiveness of the technique will decrease with time as radiocaesium migrates down the soil profile but this would be expected to occur slowly in many soils. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparison of regional and global land cover products and the implications for biogenic emission modeling.

Science.gov (United States)

Huang, Ling; McDonald-Buller, Elena; McGaughey, Gary; Kimura, Yosuke; Allen, David T

2015-10-01

Accurate estimates of biogenic emissions are required for air quality models that support the development of air quality management plans and attainment demonstrations. Land cover characterization is an essential driving input for most biogenic emissions models. This work contrasted the global Moderate Resolution Imaging Spectroradiometer (MODIS) land cover product against a regional land cover product developed for the Texas Commissions on Environmental Quality (TCEQ) over four climate regions in eastern Texas, where biogenic emissions comprise a large fraction of the total inventory of volatile organic compounds (VOCs) and land cover is highly diverse. The Model of Emissions of Gases and Aerosols from Nature (MEGAN) was utilized to investigate the influences of land cover characterization on modeled isoprene and monoterpene emissions through changes in the standard emission potential and emission activity factor, both separately and simultaneously. In Central Texas, forest coverage was significantly lower in the MODIS land cover product relative to the TCEQ data, which resulted in substantially lower estimates of isoprene and monoterpene emissions by as much as 90%. Differences in predicted isoprene and monoterpene emissions associated with variability in land cover characterization were primarily caused by differences in the standard emission potential, which is dependent on plant functional type. Photochemical modeling was conducted to investigate the effects of differences in estimated biogenic emissions associated with land cover characterization on predicted ozone concentrations using the Comprehensive Air Quality Model with Extensions (CAMx). Mean differences in maximum daily average 8-hour (MDA8) ozone concentrations were 2 to 6 ppb with maximum differences exceeding 20 ppb. Continued focus should be on reducing uncertainties in the representation of land cover through field validation. Uncertainties in the estimation of biogenic emissions associated with

Comprehensive monitoring of Bangladesh tree cover inside and outside of forests, 2000-2014

Science.gov (United States)

Potapov, P.; Siddiqui, B. N.; Iqbal, Z.; Aziz, T.; Zzaman, B.; Islam, A.; Pickens, A.; Talero, Y.; Tyukavina, A.; Turubanova, S.; Hansen, M. C.

2017-10-01

A novel approach for satellite-based comprehensive national tree cover change assessment was developed and applied in Bangladesh, a country where trees outside of forests play an important role in the national economy and carbon sequestration. Tree cover change area was quantified using the integration of wall-to-wall Landsat-based mapping with a higher spatial resolution sample-based assessment. The total national tree canopy cover area was estimated as 3165 500 ± 186 600 ha in the year 2000, with trees outside forests making up 54% of total canopy cover. Total tree canopy cover increased by 135 700 (± 116 600) ha (4.3%) during the 2000-2014 time interval. Bangladesh exhibits a national tree cover dynamic where net change is rather small, but gross dynamics significant and variable by forest type. Despite the overall gain in tree cover, results revealed the ongoing clearing of natural forests, especially within the Chittagong hill tracts. While forests decreased their tree cover area by 83 600 ha, the trees outside forests (including tree plantations, village woodlots, and agroforestry) increased their canopy area by 219 300 ha. Our results demonstrated method capability to quantify tree canopy cover dynamics within a fine-scale agricultural landscape. Our approach for comprehensive monitoring of tree canopy cover may be recommended for operational implementation in Bangladesh and other countries with significant tree cover outside of forests.

Determination Total Phosphour of Maize Plant Samples by Continuous Flow Analyzer in Comparison with Vanadium Molybdate Yellow Colorimetric Method

OpenAIRE

LIU Yun-xia; WEN Yun-jie; HUANG Jin-li; LI Gui-hua; CHAI Xiao; WANG Hong

2015-01-01

The vanadium molybdate yellow colorimetric method(VMYC method) is regarded as one of conventional methods for determining total phosphorus(P) in plants, but it is time consuming procedure. Continuous flow analyzer(CFA) is a fluid stream segmentation technique with air segments. It is used to measure P concentration based on the molybdate-antimony-ascorbic acid method of Murphy and Riley. Sixty nine of maize plant samples were selected and digested with H2SO4-H2O2. P concentrations in the dige...

Impact of vetch cover crop on runoff, soil loss, soil chemical properties and yield of chickpea in North Gondar, Ethiopia

Science.gov (United States)

Demelash, Nigus; Klik, Andreas; Holzmann, Hubert; Ziadat, Feras; Strohmeier, Stefan; Bayu, Wondimu; Zucca, Claudio; Abera, Atikilt

2016-04-01

Cover crops improve the sustainability and quality of both natural system and agro ecosystem. In Gumara-Maksegnit watershed which is located in Lake Tana basin, farmers usually use fallow during the rainy season for the preceding chickpea production system. The fallowing period can lead to soil erosion and nutrient losses. A field experiment was conducted during growing seasons 2014 and 2015 to evaluate the effect of cover crops on runoff, soil loss, soil chemical properties and yield of chickpea in North Gondar, Ethiopia. The plot experiment contained four treatments arranged in Randomized Complete Block Design with three replications: 1) Control plot (Farmers' practice: fallowing- without cover crop), 2) Chickpea planted with Di-ammonium phosphate (DAP) fertilizer with 46 k ha-1 P2O5 and 23 k ha-1 nitrogen after harvesting vetch cover crop, 3) Chick pea planted with vetch cover crop incorporated with the soil as green manure without fertilizer, 4) Chick pea planted with vetch cover crop and incorporated with the soil as green manure and with 23 k ha-1 P2O5 and 12.5 k ha-1 nitrogen. Each plot with an area of 36 m² was equipped with a runoff monitoring system. Vetch (Vicia sativa L.) was planted as cover crop at the onset of the rain in June and used as green manure. The results of the experiment showed statistically significant (P plant, above ground biomass and grain yield of chick pea. However, there was no statistically significant difference (P > 0.05) on average plant height, average number of branches and hundred seed weight. Similarly, the results indicated that cover crop has a clear impact on runoff volume and sediment loss. Plots with vetch cover crop reduce the average runoff by 65% and the average soil loss decreased from 15.7 in the bare land plot to 8.6 t ha-1 with plots covered by vetch. In general, this result reveales that the cover crops, especially vetch, can be used to improve chickpea grain yield in addition to reduce soil erosion in the

ASSESSMENT OF VEGETATION COVER ON SODA WASTE DISPOSAL SITE AT JANIKOWO, FOLLOWING 13-YEAR-LONG RECLAMATION

Directory of Open Access Journals (Sweden)

Kazimierz Henryk Dyguś

2014-10-01

Full Text Available The results are presented of vegetation survey on the alkaline and saline soda waste disposal site at Janikowo Soda Plant near Toruń (central Poland. The site was subject to reclamation using diverse techniques including sewage sludge and ash, starting from the year 2000 onwards. The survey was made to evaluate the status of plant succession as well as stability and diversity of vegetation cover. The vegetation was inventoried using the cover-frequency method, on a 10 x 10 m quadrat samples randomly distributed over the reclaimed area. Communities were classified using the Central-European approach by Braun-Blanquet (1964. In 2013, the vegetation was well established and provided a dense cover of the substrate. 108 plant species were found compared to some 5–8 plants which arrived spontaneously until the year 2000. Species richness increased 15 fold since the year when reclamation started. Species of graminoid and Asteraceae families prevailed in most patches of local vegetation. The vegetation cover on sites treated with a mixt of power plant ash and sewage sludge was less stable and less diverse than that on sites where sewage sludge only was applied. Annuals and biennials dominated in the vegetation on ash grounds while more competitive perennials prevailed on sewage sludge substrates. On the latter substrates there develop plant communities classified as an association of smooth meadow grass and common yarrow Poa pratensis-Achillea millefolium, whose species combination closely resembles that of seminatural fresh meadows. On the ash grounds, a variety of associations of ruderal plants were found with dominating Loesel mustard and common mugwort Sisymbrium loeselii-Artemisia vulgaris. Phytoindicatory methods using Ellenberg values have shown that waste substrates contained increased salt concentrations, however, there was no indication of increased heavy metal contents, as no plants tolerating excessive amounts of heavy metals were

Quantitative analysis of total retronecine esters-type pyrrolizidine alkaloids in plant by high performance liquid chromatography

International Nuclear Information System (INIS)

Zhang Fang; Wang Changhong; Xiong Aizhen; Wang Wan; Yang Li; Branford-White, Christopher J.; Wang Zhengtao; Bligh, S.W. Annie

2007-01-01

Pyrrolizidine alkaloids (PAs) are alkaloids which typically contain a necine (7-hydroxy-1-hydroxymethyl-6,7-dihydro-5H-pyrrolizidine) base unit, and they can be found in one third of the higher plants around the world. They are hepatotoxic, mutagenic and carcinogenic and pose a threat to human health and safety. A specific, quick and sensitive method is therefore needed to detect and quantify the PAs sometimes in trace amount in herbs, tea or food products. Based on high performance liquid chromatography with prior derivatization of the alkaloids using o-chloranil and Ehrlich's reagent, we report an improved method for quantitative analysis of the total amount of retronecine esters-type pyrrolizidine alkaloids (RET-PAs) in a plant extract. The total quantitation of RET-PAs is achieved because of a common colored retronecine marker, a 7-ethoxy-1-ethoxylmethyl retronecine derivative, is produced with all the different RET-PAs during the derivatization reaction. The chemical identity of the common retronecine marker was characterized on-line by positive mode electrospray ionization mass spectrometry and nuclear magnetic resonance spectroscopy. The limit of detection using the improved method is 0.26 nmol mL -1 and the limit of quantitation is 0.79 nmol mL -1 . The advantages of this method are much enhanced sensitivity in detection and quantitation, and, no restriction on the choice of RET-PA as a calibration standard. Application of the developed method to the quantitation of total RET esters-type PAs in Senecio scandens from different regions of China is also reported

Quantitative analysis of total retronecine esters-type pyrrolizidine alkaloids in plant by high performance liquid chromatography

Energy Technology Data Exchange (ETDEWEB)

Zhang Fang; Wang Changhong; Xiong Aizhen; Wang Wan; Yang Li [Key Laboratory of Standardization of Chinese Medicines of Ministry of Education, Shanghai University of Traditional Chinese Medicine, 1200 Cai Lun Road, Zhangjiang Hi-Tech Park, Shanghai 201203 (China); Branford-White, Christopher J. [Institute for Health Research and Policy, London Metropolitan University, 166-220 Holloway Road, London N7 8DB (United Kingdom); Wang Zhengtao [Key Laboratory of Standardization of Chinese Medicines of Ministry of Education, Shanghai University of Traditional Chinese Medicine, 1200 Cai Lun Road, Zhangjiang Hi-Tech Park, Shanghai 201203 (China); School of Chinese Pharmacy, China Pharmaceutical University, Nanjing 210038 (China)], E-mail: wangzt@shutcm.edu.cn; Bligh, S.W. Annie [Institute for Health Research and Policy, London Metropolitan University, 166-220 Holloway Road, London N7 8DB (United Kingdom)], E-mail: a.bligh@londonmet.ac.uk

2007-12-12

Pyrrolizidine alkaloids (PAs) are alkaloids which typically contain a necine (7-hydroxy-1-hydroxymethyl-6,7-dihydro-5H-pyrrolizidine) base unit, and they can be found in one third of the higher plants around the world. They are hepatotoxic, mutagenic and carcinogenic and pose a threat to human health and safety. A specific, quick and sensitive method is therefore needed to detect and quantify the PAs sometimes in trace amount in herbs, tea or food products. Based on high performance liquid chromatography with prior derivatization of the alkaloids using o-chloranil and Ehrlich's reagent, we report an improved method for quantitative analysis of the total amount of retronecine esters-type pyrrolizidine alkaloids (RET-PAs) in a plant extract. The total quantitation of RET-PAs is achieved because of a common colored retronecine marker, a 7-ethoxy-1-ethoxylmethyl retronecine derivative, is produced with all the different RET-PAs during the derivatization reaction. The chemical identity of the common retronecine marker was characterized on-line by positive mode electrospray ionization mass spectrometry and nuclear magnetic resonance spectroscopy. The limit of detection using the improved method is 0.26 nmol mL{sup -1} and the limit of quantitation is 0.79 nmol mL{sup -1}. The advantages of this method are much enhanced sensitivity in detection and quantitation, and, no restriction on the choice of RET-PA as a calibration standard. Application of the developed method to the quantitation of total RET esters-type PAs in Senecio scandens from different regions of China is also reported.

Community-level plant-soil feedbacks explain landscape distribution of native and non-native plants.

Science.gov (United States)

Kulmatiski, Andrew

2018-02-01

Plant-soil feedbacks (PSFs) have gained attention for their potential role in explaining plant growth and invasion. While promising, most PSF research has measured plant monoculture growth on different soils in short-term, greenhouse experiments. Here, five soil types were conditioned by growing one native species, three non-native species, or a mixed plant community in different plots in a common-garden experiment. After 4 years, plants were removed and one native and one non-native plant community were planted into replicate plots of each soil type. After three additional years, the percentage cover of each of the three target species in each community was measured. These data were used to parameterize a plant community growth model. Model predictions were compared to native and non-native abundance on the landscape. Native community cover was lowest on soil conditioned by the dominant non-native, Centaurea diffusa , and non-native community cover was lowest on soil cultivated by the dominant native, Pseudoroegneria spicata . Consistent with plant growth on the landscape, the plant growth model predicted that the positive PSFs observed in the common-garden experiment would result in two distinct communities on the landscape: a native plant community on native soils and a non-native plant community on non-native soils. In contrast, when PSF effects were removed, the model predicted that non-native plants would dominate all soils, which was not consistent with plant growth on the landscape. Results provide an example where PSF effects were large enough to change the rank-order abundance of native and non-native plant communities and to explain plant distributions on the landscape. The positive PSFs that contributed to this effect reflected the ability of the two dominant plant species to suppress each other's growth. Results suggest that plant dominance, at least in this system, reflects the ability of a species to suppress the growth of dominant competitors

The Use of Cover Crops as Climate-Smart Management in Midwest Cropping Systems

Science.gov (United States)

Basche, A.; Miguez, F.; Archontoulis, S.; Kaspar, T.

2014-12-01

The observed trends in the Midwestern United States of increasing rainfall variability will likely continue into the future. Events such as individual days of heavy rain as well as seasons of floods and droughts have large impacts on agricultural productivity and the natural resource base that underpins it. Such events lead to increased soil erosion, decreased water quality and reduced corn and soybean yields. Winter cover crops offer the potential to buffer many of these impacts because they essentially double the time for a living plant to protect and improve the soil. However, at present, cover crops are infrequently utilized in the Midwest (representing 1-2% of row cropped land cover) in particular due to producer concerns over higher costs and management, limited time and winter growing conditions as well as the potential harm to corn yields. In order to expand their use, there is a need to quantify how cover crops impact Midwest cropping systems in the long term and namely to understand how to optimize the benefits of cover crops while minimizing their impacts on cash crops. We are working with APSIM, a cropping systems platform, to specifically quantify the long term future impacts of cover crop incorporation in corn-based cropping systems. In general, our regional analysis showed only minor changes to corn and soybean yields (<1% differences) when a cover crop was or was not included in the simulation. Further, a "bad spring" scenario (where every third year had an abnormally wet/cold spring and cover crop termination and planting cash crop were within one day) did not result in any major changes to cash crop yields. Through simulations we estimate an average increase of 4-9% organic matter improvement in the topsoil and an average decrease in soil erosion of 14-32% depending on cover crop planting date and growth. Our work is part of the Climate and Corn-based Cropping Systems Coordinated Agriculture Project (CSCAP), a collaboration of eleven Midwestern

Poultry Plant Noise Control

Science.gov (United States)

1982-01-01

A demonstration conducted last winter at the Tip Top Poultry Plant intended to show poultry plant managers from all over the U.S. potential solutions to the problem of plant noise. Plastic covers used over sound absorbing materials need to meet cleanability requirements, high- pressure water cleaning and other harsh maintenance procedures peculiar to the poultry processing industry. For the demonstration, Fiber Flex, Inc. manufactured and donated 750 noise panels; Owens-Corning Fiberglas Corporation donated the fiberglas cores; and the cover material was purchased from Howe and Bainbridge. The Engineering Experiment Station (EES) conducted before and after noise surveys and is evaluating the effect of noise reduction on turnover and productivity in the demonstration plant. EES plans to conduct a noise abatement workshop and update a handbook to help poultry processors with noise problems. EES study and demonstration may be applicable to other food processing plants where similar sanitary constraints exist.

Strategies for preventing invasive plant outbreaks after prescribed fire in ponderosa pine forest

Science.gov (United States)

Symstad, Amy J.; Newton, Wesley E.; Swanson, Daniel J.

2014-01-01

Land managers use prescribed fire to return a vital process to fire-adapted ecosystems, restore forest structure from a state altered by long-term fire suppression, and reduce wildfire intensity. However, fire often produces favorable conditions for invasive plant species, particularly if it is intense enough to reveal bare mineral soil and open previously closed canopies. Understanding the environmental or fire characteristics that explain post-fire invasive plant abundance would aid managers in efficiently finding and quickly responding to fire-caused infestations. To that end, we used an information-theoretic model-selection approach to assess the relative importance of abiotic environmental characteristics (topoedaphic position, distance from roads), pre-and post-fire biotic environmental characteristics (forest structure, understory vegetation, fuel load), and prescribed fire severity (measured in four different ways) in explaining invasive plant cover in ponderosa pine forest in South Dakota’s Black Hills. Environmental characteristics (distance from roads and post-fire forest structure) alone provided the most explanation of variation (26%) in post-fire cover of Verbascum thapsus (common mullein), but a combination of surface fire severity and environmental characteristics (pre-fire forest structure and distance from roads) explained 36–39% of the variation in post-fire cover of Cirsium arvense (Canada thistle) and all invasives together. For four species and all invasives together, their pre-fire cover explained more variation (26–82%) in post-fire cover than environmental and fire characteristics did, suggesting one strategy for reducing post-fire invasive outbreaks may be to find and control invasives before the fire. Finding them may be difficult, however, since pre-fire environmental characteristics explained only 20% of variation in pre-fire total invasive cover, and less for individual species. Thus, moderating fire intensity or targeting areas

Effects of weed cover composition on insect pest and natural enemy abundance in a field of Dracaena marginata (Asparagales: Asparagaceae) in Costa Rica.

Science.gov (United States)

Sadof, Clifford S; Linkimer, Mildred; Hidalgo, Eduardo; Casanoves, Fernando; Gibson, Kevin; Benjamin, Tamara J

2014-04-01

Weeds and their influence on pest and natural enemy populations were studied on a commercial ornamental farm during 2009 in the Atlantic Zone of Costa Rica. A baseline survey of the entire production plot was conducted in February, along a 5 by 5 m grid to characterize and map initial weed communities of plants, cicadellids, katydids, and armored scales. In total, 50 plant species from 21 families were found. Seven weed treatments were established to determine how weed manipulations would affect communities of our targeted pests and natural enemies. These treatments were selected based on reported effects of specific weed cover on herbivorous insects and natural enemies, or by their use by growers as a cover crop. Treatments ranged from weed-free to being completely covered with endemic species of weeds. Although some weed treatments changed pest abundances, responses differed among arthropod pests, with the strongest effects observed for Caldwelliola and Empoasca leafhoppers. Removal of all weeds increased the abundance of Empoasca, whereas leaving mostly cyperacaeous weeds increased the abundance of Caldwelliola. Weed manipulations had no effect on the abundance of katydid and scale populations. No weed treatment reduced the abundance of all three of the target pests. Differential responses of the two leafhopper species to the same weed treatments support hypotheses, suggesting that noncrop plants can alter the abundance of pests through their effects on arthropod host finding and acceptance, as well as their impacts on natural enemies.

Total Measurement Uncertainty for the Plutonium Finishing Plant (PFP) Segmented Gamma Scan Assay System

CERN Document Server

Fazzari, D M

2001-01-01

This report presents the results of an evaluation of the Total Measurement Uncertainty (TMU) for the Canberra manufactured Segmented Gamma Scanner Assay System (SGSAS) as employed at the Hanford Plutonium Finishing Plant (PFP). In this document, TMU embodies the combined uncertainties due to all of the individual random and systematic sources of measurement uncertainty. It includes uncertainties arising from corrections and factors applied to the analysis of transuranic waste to compensate for inhomogeneities and interferences from the waste matrix and radioactive components. These include uncertainty components for any assumptions contained in the calibration of the system or computation of the data. Uncertainties are propagated at 1 sigma. The final total measurement uncertainty value is reported at the 95% confidence level. The SGSAS is a gamma assay system that is used to assay plutonium and uranium waste. The SGSAS system can be used in a stand-alone mode to perform the NDA characterization of a containe...

Importance of husk covering on field infestation of maize by ...

African Journals Online (AJOL)

STORAGESEVER

2008-10-20

Oct 20, 2008 ... An experiment was conducted to determine the importance of husk covering on field infestation of maize by the maize ... high yielding plants with no consideration for resistance ..... provided financial support for the study.

Total and Bioaccessible Soil Arsenic and Lead Levels and Plant Uptake in Three Urban Community Gardens in Puerto Rico

Directory of Open Access Journals (Sweden)

John Misenheimer

2018-01-01

Full Text Available Arsenic (As and lead (Pb are two contaminants of concern associated with urban gardening. In Puerto Rico, data currently is limited on As and Pb levels in urban garden soils, soil metal (loid bioaccessibility, and uptake of As and Pb in soil by edible plants grown in the region. This study examined total and bioaccessible soil As and Pb concentrations and accumulation in 10 commonly grown garden plants collected from three urban community gardens in Puerto Rico. Bioavailability values were predicted using bioaccessibility data to compare site-specific bioavailability estimates to commonly used default exposure assumptions. Total and bioaccessible As levels in study soils ranged from 2 to 55 mg/kg and 1 to 18 mg/kg, respectively. Total and bioaccessible Pb levels ranged from 19 to 172 mg/kg and 17 to 97 mg/kg, respectively. Measured bioaccessibility values corresponded to 19% to 42% bioaccessible As and 61% to 100% bioaccessible Pb when expressed as a percent of total As and Pb respectively. Predicted relative percent bioavailability of soil As and Pb based on measured bioaccessibility values ranged from 18% to 36% and 51% to 85% for As and Pb respectively. Transfer factors (TFs measuring uptake of As in plants from soil ranged from 0 to 0.073 in the edible flesh (fruit or vegetable of plant tissues analyzed and 0.073 to 0.444 in edible leaves. Pb TFs ranged from 0.002 to 0.012 in flesh and 0.023 to 0.204 in leaves. Consistent with TF values, leaves accumulated higher concentrations of As and Pb than the flesh, with the highest tissue concentrations observed in the culantro leaf (3.2 mg/kg dw of As and 8.9 mg/kg dw of Pb. Leaves showed a general but not statistically-significant (α = 0.05 trend of increased As and Pb concentration with increased soil levels, while no trend was observed for flesh tissues. These findings provide critical data that can improve accuracy and reduce uncertainty when conducting site-specific risk determination of

Fiscal Year 1993 Well Plugging and Abandonment Program Summary Report Y-12 Plant, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-09-01

This report is a synopsis of the progress of the well plugging and abandonment program at the Y-12 Plant, Oak Ridge, Tennessee, from October 1993 through August 1994. A total of 57 wells and borings were plugged and abandoned during the period of time covered in this report. All wells and borings were plugged and abandoned in accordance with the Monitoring Well Plugging and Abandonment Plan for the U.S. Department of Energy, Y-12 Plant, Oak Ridge, Tennessee.

Some interactive factors affecting trench-cover integrity on low-level waste sites

International Nuclear Information System (INIS)

Hakonson, T.E.; Lane, L.J.; Steger, J.G.; DePoorter, G.L.

1982-01-01

This paper describes important mechanisms by which radionuclide can be transported from low-level waste disposal sites into biological pathways, discuss interactions of abiotic and biotic processes, and recommends environmental characteristics that should be measured to design sites that minimize this transport. Past experience at shallow land burial sites for low-level radioactive wastes suggest that occurrences of waste exposure and radionuclide transport are often related to inadequate trench cover designs. Meeting performance standards at low-level waste sites can only be achieved by recognizing that physical, chemical, and biological processes operating on and in a trench cover profile are highly interactive. Failure to do so can lead to improper design criteria and subsequent remedial action procedures that can adversely affect site stability. Based upon field experiments and computer modeling, recommendations are made on site characteristics that require measurement in order to design systems that reduce surface runoff and erosion, manage soil moisture and biota in the cover profile to maximize evapotranspiration and minimize percolation, and place bounds on the intrusion potential of plants and animals into the waste material. Major unresolved problems include developing probabilistic approaches that include climatic variability, improved knowledge of soil-water-plant-erosion relationships, development of practical vegetation establishment and maintenance procedures, prediction and quantification of site potential and plant succession, and understanding the interaction of processes occurring on and in the cover profile with deeper subsurface processes

Effect of removal of hesperis matronalis (Dame's rocket) on species cover of forest understory vegetation in NW indiana

Science.gov (United States)

Pavlovic, N.B.; Leicht-Young, S. A.; Frohnapple, K.J.; Grundel, R.

2009-01-01

Exotic invasive plant species differ in their effects on indigenous vegetation as evidenced by research evaluating community response to their removal. We used a removal approach to quantify the response of a mesic woodland to the removal versus retention of an invasive plant, Hesperis matronalis (dame's rocket) from paired treatment plots over 3 y. Cover of H. matronalis did not differ between control and treatment plots prior to removal, declined in the removal plots and remained significantly lower in cover compared to the control plots. Removal did not significantly affect species richness and species diversity (evenness, Shannon and Simpson) at the plot scale, but did result in increased species richness overall in the removal plots in the last sampling year when compared to control plots. Non-metric multidimensional scaling ordination analysis indicated a significant compositional change in the spring plant composition of plots over the 3 y, reflecting an increase in exotic woody species. Exotic woody plants, especially Rosa multiflora and Euonymus alatus, increased in cover in response to H. matronalis removal. In the 3 y, neither native nor exotic forbs, nor native woody plants responded to the removal of H. matronalis in a statistically significant manner. The increasing cover of woody invasive plants in response to the removal of H. matronalis has important management implications for restoration of degraded communities.

Effect of urdbean leaf crinkle virus infection on total soluble protein and antioxidant enzymes in blackgram plants

International Nuclear Information System (INIS)

Ashfaq, M.; Mughal, S.M.; Khan, A.; Javed, N.; Sahi, S.T.; Shahid, M.

2010-01-01

Urdbean leaf crinkle virus (ULCV) is a common, wide spread, destructive and economically important disease causing systemic infection in blackgram (Vigna mungo (L.) Hepper), resulting in extreme crinkling, curling, puckering and rugosity of leaves, and yield reductions. Effect of viral infection was investigated on total soluble proteins and antioxidant enzymes activity in two genotypes viz., Mash-88-susceptible and CM-2002-resistant, at different growth stages under both the inoculated and un-inoculated conditions. ULCV infection resulted in significant increase in total soluble protein contents of the leaves in both genotypes. In healthy plant, super oxide dismutase (SOD), catalase (CAT) and peroxidase (PO) showed similar activity levels. In inoculated plants of Mash-88, SOD and PO activities decreased and increased non-significantly at all growth stages, respectively. The activities of PO and SOD increased and decreased significantly after 15 and 30 days of inoculation in resistant genotype, respectively. No significant changes in catalase (CAT) activity were detected in ULCV-infected leaves over the control. It was concluded that the super oxide dismutase and peroxidases might be associated with resistance/susceptibility to ULCV infection. (author)

Seed plant features, distribution patterns, diversity hotspots, and conservation gaps in Xinjiang, China

Directory of Open Access Journals (Sweden)

Jihong Huang

2018-06-01

Full Text Available The flora in Xinjiang is unique. Decisions about biodiversity conservation and management based on seed plant diversity hotspots and conservation gaps in Xinjiang are essential to maintain this unique flora. Based on a species distribution dataset of seed plants, we measured seed plant diversity using species richness and phylogenetic diversity indices. Five percent of Xinjiang’s total land area with the highest biodiversity was used to identify hotspots for each index. In total, eight hotspots were identified. Most hotspots were located in mountainous areas, mainly in the Tianshan Mountains and Altai Mountains. Furthermore, we detected conservation gaps for Xinjiang’s seed flora hotspots by overlaying nature reserve maps on to maps of identified hotspots and we designated priority conservation gaps for hotspots by overlaying global biodiversity hotspot maps on to hotspot conservation gaps maps. Most of Xinjiang’s seed plant hotspots are poorly protected; only 10.45% of these hotspots were covered by nature reserves. We suggest that it is essential to promote network function of nature reserves within these hotspots in Xinjiang to conserve this unique flora.

Large-scale biotic interaction effects - tree cover interacts with shade toler-ance to affect distribution patterns of herb and shrub species across the Alps

DEFF Research Database (Denmark)

Nieto-Lugilde, Diego; Lenoir, Jonathan; Abdulhak, Sylvain

2012-01-01

on the occurrence on light-demanding species via size-asymmetric competition for light, but a facilitative effect on shade-tolerant species. In order to compare the relative importance of tree cover, four models with different combinations of variables (climate, soil and tree cover) were run for each species. Then...... role. Results indicated that high tree cover causes range contraction, especially at the upper limit, for light-demanding species, whereas it causes shade-tolerant species to extend their range upwards and downwards. Tree cover thus drives plant-plant interactions to shape plant species distribution...

Energy conservation and management strategies in Heavy Water Plants

International Nuclear Information System (INIS)

Kamath, H.S.

2002-01-01

In the competitive industrial environment it is essential that cost of the product is kept at the minimum possible. Energy conservation is an important aspect in achieving this as energy is one of the key recourses for growth and survival of industry. The process of heavy water production being very complex and energy intensive, Heavy Water board has given a focussed attention for initiating various measures for reducing the specific energy consumption in all the plants. The initiative resulted in substantial reduction in specific energy consumption and brought in savings in cost. The cumulative reduction of specific energy consumption has been over 30% over the last seven years and the total savings for the last three years on account of the same has been about Rs. 190 crore. The paper describes the strategies adopted in the heavy water plants for effecting the above achievements. The paper covers the details of some of the energy saving schemes carried out at different heavy water plants through case studies. The case studies of schemes implemented at HWPs are general in nature and is applicable for any other industry. The case studies cover the modifications with re-optimisation of the process parameters, improvements effected in utility units like refrigeration and cooling water systems, improvements in captive power plant cycle and improved recycle scheme for water leading to reduced consumptions. The paper also mentions the innovative ammonia absorption refrigeration with improved coefficient of performance and HWB's efforts in development of the system as an integrated unit of the ammonia water deuterium exchange process for heavy water production. HWB also has taken up R and D on various other schemes for improvements in energy consumption for future activities covering utilisation of low grade energy for generation of refrigeration. (author)

AERATION OF THE ICE-COVERED WATER POOLS USING THE WAVE FLOW AERATOR

Directory of Open Access Journals (Sweden)

Solomin E.E

2013-12-01

Full Text Available This article describes the technical advantages and economic benefits of the ice-covered pool aeration plants consuming power from renewable energy sources. We made a comparative evaluation of the wave flow-aeration method and other methods of pool aeration. We showed the indexes and the characteristics of the wave flow-maker for aeration of ice-covered pools on the territory of Russia. We also made calculations of the economic benefits of aeration plants using the devices converting renewable energy. The project can be scaled and extended to the territory of the CIS, Europe, USA and Canada in the changing climate conditions and the variety of feed reservoirs around the world.

The drivers of plant diversity

DEFF Research Database (Denmark)

Jensen, Kristine Engemann

dataset consisting of 72,533 vascular plant species in 432 families covering the New World. Eight plant growth forms were defined based on woodiness, structure, and root traits, and species names were standardized to the latest accepted scientific name. The data is used in Paper II and IV In Paper II we....... The study emphasise that using big, collected datasets is not without limitations, and we recommend using rarefaction for species richness estimation from such datasets. Paper IV investigates a well-known macroecological pattern, the latitudinal diversity gradient, for nine vascular plant functional groups......In this thesis we use a “big data” approach to describe and explain large-scale patterns of plant diversity. The botanical data used for the six papers come from three different databases covering the New World, North America, and Europe respectively. The data on plant distributions were combined...

Effects of elevated root zone CO2 and air temperature on photosynthetic gas exchange, nitrate uptake, and total reduced nitrogen content in aeroponically grown lettuce plants.

Science.gov (United States)

He, Jie; Austin, Paul T; Lee, Sing Kong

2010-09-01

Effects of elevated root zone (RZ) CO(2) and air temperature on photosynthesis, productivity, nitrate (NO(3)(-)), and total reduced nitrogen (N) content in aeroponically grown lettuce plants were studied. Three weeks after transplanting, four different RZ [CO(2)] concentrations [ambient (360 ppm) and elevated concentrations of 2000, 10,000, and 50,000 ppm] were imposed on plants grown at two air temperature regimes of 28 degrees C/22 degrees C (day/night) and 36 degrees C/30 degrees C. Photosynthetic CO(2) assimilation (A) and stomatal conductance (g(s)) increased with increasing photosynthetically active radiation (PAR). When grown at 28 degrees C/22 degrees C, all plants accumulated more biomass than at 36 degrees C/30 degrees C. When measured under a PAR >or=600 micromol m(-2) s(-1), elevated RZ [CO(2)] resulted in significantly higher A, lower g(s), and higher midday leaf relative water content in all plants. Under elevated RZ [CO(2)], the increase of biomass was greater in roots than in shoots, causing a lower shoot/root ratio. The percentage increase in growth under elevated RZ [CO(2)] was greater at 36 degrees C/30 degrees C although the total biomass was higher at 28 degrees C/22 degrees C. NO(3)(-) and total reduced N concentrations of shoot and root were significantly higher in all plants under elevated RZ [CO(2)] than under ambient RZ [CO(2)] of 360 ppm at both temperature regimes. At each RZ [CO(2)], NO(3)(-) and total reduced N concentration of shoots were greater at 28 degrees C/22 degrees C than at 36 degrees C/30 degrees C. At all RZ [CO(2)], roots of plants at 36 degrees C/30 degrees C had significantly higher NO(3)(-) and total reduced N concentrations than at 28 degrees C/22 degrees C. Since increased RZ [CO(2)] caused partial stomatal closure, maximal A and maximal g(s) were negatively correlated, with a unique relationship for each air temperature. However, across all RZ [CO(2)] and temperature treatments, there was a close correlation between

Car Covers | Outdoor Covers Canada

OpenAIRE

Covers, Outdoor

2018-01-01

Protect your car from the elements with Ultimate Touch Car Cover. The multi-layer non-woven fabric is soft on the finish and offers 4 seasons all weather protection.https://outdoorcovers.ca/car-covers/

Assessing quality and quantity of groundwater DOC in relation to plant export from different over-winter green-cover treatments in tillage farming systems

Science.gov (United States)

Premrov, Alina; Coxon, Catherine; Hackett, Richard; Richards, Karl

2010-05-01

The biogeochemistry of nitrogen is often connected to carbon and C/N dynamics. The dissolved organic carbon (DOC) electron donor availability can be related to groundwater denitrification (Buss, et al. 2005). Therefore groundwater nitrate attenuation processes are also frequently linked to carbon availability. In recent years the role of over-winter green cover in tillage farming has been studied extensively. Nevertheless further research on the biogeochemical effect of green cover on soil/sediment and groundwater quality is still needed. In particular plant roots are known to exude different types of organic compounds, but their role in groundwater quality has not been investigated in depth. According to Cannavo et al. (2004a,b), in addition to quantity, the quality of water-extractable soil organic matter (e.g. molecular size/weight) has also an important role for microbial activity. In this study we investigate the effect of over-winter green-cover on potential DOC export to shallow groundwater (2 - 5 m below ground level), located on tillage land in Oak Park, Carlow, Ireland. The experiment includes three over-winter green-cover treatments: natural green-cover, mustard and no-cover (sprayed with herbicide following harvest); and is underlain by a sand and gravel aquifer. The site is equipped with 4 shallow piezometers per treatment (total no. of piezometers is 20, including treatments and surrounding piezometers). In addition to monitoring the quantity of DOC concentrations in shallow groundwater under different green cover treatments over time, an attempt was made to evaluate the quality of dissolved organic matter in shallow groundwater using Excitation Emission Fluorescence Matrix (EEFM) profiles obtained from analyses performed on a Varian Fluorescence Spectrophotometer of a single batch of samples (from all 20 installed piezometers in September 2009). To evaluate the quality of dissolved organic matter in shallow groundwater, computation of the

Effect of management systems and cover crops on organic matter dynamics of soil under vegetables

Directory of Open Access Journals (Sweden)

Rodrigo Fernandes de Souza

2014-06-01

Full Text Available Vegetable production in conservation tillage has increased in Brazil, with positive effects on the soil quality. Since management systems alter the quantity and quality of organic matter, this study evaluated the influence of different management systems and cover crops on the organic matter dynamics of a dystrophic Red Latosol under vegetables. The treatments consisted of the combination of three soil tillage systems: no-tillage (NT, reduced tillage (RT and conventional tillage (CT and of two cover crops: maize monoculture and maize-mucuna intercrop. Vegetables were grown in the winter and the cover crops in the summer for straw production. The experiment was arranged in a randomized block design with four replications. Soil samples were collected between the crop rows in three layers (0.0-0.05, 0.05-0.10, and 0.10-0.30 m twice: in October, before planting cover crops for straw, and in July, during vegetable cultivation. The total organic carbon (TOC, microbial biomass carbon (MBC, oxidizable fractions, and the carbon fractions fulvic acid (C FA, humic acid (C HA and humin (C HUM were determined. The main changes in these properties occurred in the upper layers (0.0-0.05 and 0.05-0.10 m where, in general, TOC levels were highest in NT with maize straw. The MBC levels were lowest in CT systems, indicating sensitivity to soil disturbance. Under mucuna, the levels of C HA were lower in RT than NT systems, while the C FA levels were lower in RT than CT. For vegetable production, the C HUM values were lowest in the 0.05-0.10 m layer under CT. With regard to the oxidizable fractions, the tillage systems differed only in the most labile C fractions, with higher levels in NT than CT in the 0.0-0.05 m layer in both summer and winter, with no differences between these systems in the other layers. The cabbage yield was not influenced by the soil management system, but benefited from the mulch production of the preceding maize-mucuna intercrop as cover

Optimization of the Area 5 Radioactive Waste Management Site Closure Cover

Energy Technology Data Exchange (ETDEWEB)

Shott, Greg; Yucel, Vefa

2009-04-01

The U.S. Department of Energy Manual DOE M 435.1-1, “Radioactive Waste Management Manual,” requires that performance assessments demonstrate that releases of radionuclides to the environment are as low as reasonably achievable (ALARA). Quantitative cost benefit analysis of radiation protection options is one component of the ALARA process. This report summarizes a quantitative cost benefit analysis of closure cover thickness for the Area 5 Radioactive Waste Management Site (RWMS) on the Nevada Test Site. The optimum cover thickness that maintains doses ALARA is shown to be the thickness with the minimum total closure cost. Total closure cost is the sum of cover construction cost and the health detriment cost. Cover construction cost is estimated based on detailed cost estimates for closure of the 92-acre Low-Level Waste Management Unit (LLWMU). The health detriment cost is calculated as the product of collective dose and a constant monetary value of health detriment in units of dollars per unit collective dose. Collective dose is the sum of all individual doses in an exposed population and has units of person-sievert (Sv). Five discrete cover thickness options ranging from 2.5 to 4.5 meters (m) (8.2 to 15 feet [ft]) are evaluated. The optimization was subject to the constraints that (1) options must meet all applicable regulatory requirements and that (2) individual doses be a small fraction of background radiation dose. Total closure cost is found to be a monotonically increasing function of cover thickness for the 92-ac LLWMU, the Northern Expansion Area, and the entire Area 5 RWMS. The cover construction cost is orders of magnitude greater than the health detriment cost. Two-thousand Latin hypercube sampling realizations of the relationship between total closure cost and cover thickness are generated. In every realization, the optimum cover thickness is 2.5 m (8.2 ft) for the 92-ac Low-Level Waste Management Unit, the Northern Expansion Area, and the entire

Optimization of the Area 5 Radioactive Waste Management Site Closure Cover

International Nuclear Information System (INIS)

Shott, Greg; Yucel, Vefa

2009-01-01

The U.S. Department of Energy Manual DOE M 435.1-1, 'Radioactive Waste Management Manual,' requires that performance assessments demonstrate that releases of radionuclides to the environment are as low as reasonably achievable (ALARA). Quantitative cost benefit analysis of radiation protection options is one component of the ALARA process. This report summarizes a quantitative cost benefit analysis of closure cover thickness for the Area 5 Radioactive Waste Management Site (RWMS) on the Nevada Test Site. The optimum cover thickness that maintains doses ALARA is shown to be the thickness with the minimum total closure cost. Total closure cost is the sum of cover construction cost and the health detriment cost. Cover construction cost is estimated based on detailed cost estimates for closure of the 92-acre Low-Level Waste Management Unit (LLWMU). The health detriment cost is calculated as the product of collective dose and a constant monetary value of health detriment in units of dollars per unit collective dose. Collective dose is the sum of all individual doses in an exposed population and has units of person-sievert (Sv). Five discrete cover thickness options ranging from 2.5 to 4.5 meters (m) (8.2 to 15 feet (ft)) are evaluated. The optimization was subject to the constraints that (1) options must meet all applicable regulatory requirements and that (2) individual doses be a small fraction of background radiation dose. Total closure cost is found to be a monotonically increasing function of cover thickness for the 92-ac LLWMU, the Northern Expansion Area, and the entire Area 5 RWMS. The cover construction cost is orders of magnitude greater than the health detriment cost. Two-thousand Latin hypercube sampling realizations of the relationship between total closure cost and cover thickness are generated. In every realization, the optimum cover thickness is 2.5 m (8.2 ft) for the 92-ac Low-Level Waste Management Unit, the Northern Expansion Area, and the entire Area

Fast reactor cover gas purification - The UK position

Energy Technology Data Exchange (ETDEWEB)

Thorley, A W

1987-07-01

The cover gas in the Prototype Fast Reactor (PFR) provides an inert gas blanket for both primary and secondary sodium circuits, ensures inert gas padding exists between the upper seals associated with penetrations through the reactor roof and provides argon to items of plant such as the control rods and the rotating shield and also to on line instruments such as the secondary circuit Katharometers. In order to meet these and other requirements purification of the argon cover gas is important to ensure: gas fed to purge gaps in the area of the magnetic hold device in the control rod mechanisms is not laden with sodium aerosols and reactive impurities (O{sub 2}, H{sub 2}) which could cause blocking both within the gaps and pipelines; gas phase detection systems which provide early warning of steam generator failures or oil ingress into the sodium are not affected by the presence of gaseous impurities such as H{sub 2}, CO/CO{sub 2} and CH{sub 4}; mass transfer processes involving both corrosion products and interstitial atoms cannot be sustained in the cover gas environment due to the presence of high levels of O{sub 2}, N{sub 2} and carburising gases; background levels of radioactivity (eg Xe 133) are sufficiently low to enable gas phase detection of failed fuel pins, and the primary circuit gas blanket activity is sufficiently reduced so that discharges to the atmosphere are minimised. This paper describes how the PFR cover gas purification system is coping with these various items and how current thinking regarding the design of cover gas purification systems for a Civil Demonstration Fast Reactor (CDFR), where larger gas volumes and higher levels of radioactivity may be involved, is being guided by current experience on PFR. The paper also briefly review the experimental work planned to study aerosol and caesium behaviour in cove gas environments and discusses the behaviour of those impurities such as Zn, oil and N{sub 2} which are potentially damaging if certain

Fast reactor cover gas purification - The UK position

International Nuclear Information System (INIS)

Thorley, A.W.

1987-01-01

The cover gas in the Prototype Fast Reactor (PFR) provides an inert gas blanket for both primary and secondary sodium circuits, ensures inert gas padding exists between the upper seals associated with penetrations through the reactor roof and provides argon to items of plant such as the control rods and the rotating shield and also to on line instruments such as the secondary circuit Katharometers. In order to meet these and other requirements purification of the argon cover gas is important to ensure: gas fed to purge gaps in the area of the magnetic hold device in the control rod mechanisms is not laden with sodium aerosols and reactive impurities (O 2 , H 2 ) which could cause blocking both within the gaps and pipelines; gas phase detection systems which provide early warning of steam generator failures or oil ingress into the sodium are not affected by the presence of gaseous impurities such as H 2 , CO/CO 2 and CH 4 ; mass transfer processes involving both corrosion products and interstitial atoms cannot be sustained in the cover gas environment due to the presence of high levels of O 2 , N 2 and carburising gases; background levels of radioactivity (eg Xe 133) are sufficiently low to enable gas phase detection of failed fuel pins, and the primary circuit gas blanket activity is sufficiently reduced so that discharges to the atmosphere are minimised. This paper describes how the PFR cover gas purification system is coping with these various items and how current thinking regarding the design of cover gas purification systems for a Civil Demonstration Fast Reactor (CDFR), where larger gas volumes and higher levels of radioactivity may be involved, is being guided by current experience on PFR. The paper also briefly review the experimental work planned to study aerosol and caesium behaviour in cove gas environments and discusses the behaviour of those impurities such as Zn, oil and N 2 which are potentially damaging if certain levels are exceeded in operating

Emergency procedures of nuclear power plants-Evolution

International Nuclear Information System (INIS)

Atalla, D.L.

1988-01-01

During the TMI event the operators had some difficulties to accurately diagnose the accident, causing delay to recover the plant, and allowing the conditions to deteriorate. Further analysis concluded that the plant emergency procedures were incomplete, and did not cover the possibility of multiple and simultaneous failures. This paper covers a new approach for developing emergency procedures to create a new general strategy by providing valid instructions for all kinds of possible incidents in a nuclear power plant. (author) [pt

Clouds cover variability in São Paulo

Directory of Open Access Journals (Sweden)

Luciana Machado de Moura

2016-11-01

Full Text Available Clouds cover observations are performed by visual inspection which determines the fraction of the sky that is overcast. However, visual observation of clouds cover is a very subjective method, and can vary significantly among observers. This study examined the variability in clouds cover over the city of São Paulo between 1961 and 2013, using clouds cover fraction data observed at the weather station operated by IAG / USP. The study also used two techniques based on visible radiance data observed by the GOES-10 satellite in order to indirectly estimate clouds cover. In order to ensure consistency, the estimated and observed cloudiness was compared with the clearness index, which is the ratio between the total solar radiation observed at the weather station and the incoming solar irradiation at the top of atmosphere. The study found consistency between the various databases that showed similar behavior in all of the seasons of the year. The largest cloudiness values occurred in the summer and lowest in the winter.

Power plant chemical technology

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-12-01

17 contributions covering topies of fossil fuel combustion, flue gas cleaning, power plant materials, corrosion, water/steam cycle chemistry, monitoring and control were presented at the annual meeting devoted to Power Plant Chemical Technology 1996 at Kolding (Denmark) 4-6 September 1996. (EG)

Application of total quality tools in the operational process modernization and optimization of large hydroelectric power plants; Aplicacao de ferramentas da qualidade total na modernizacao e otimizacao de processos operacionais de grandes usinas hidreletricas

Energy Technology Data Exchange (ETDEWEB)

Potenza, Luiz Frederico; Kassem, Faisal Ali; Medlo, Gerson Ricardo; Santos, Valdemir Chalito dos [Companhia Paranaense de Energia (COPEL), Capitao Leonidas Marques, PR (Brazil). Superintendencia de Gerencia da Manutencao. Area de Operacao e Manutencao Salto Caxias]. E-mail: potenza@mail.copel.br

1998-07-01

This work highlights a practical example of Total Quality tools application, and as the institutional changes advances, the necessity of being better and more competitive becomes evident. By using Total Quality Control tools in the modernization and optimization of operational processes for large hydroelectric power plants of the COPEL-Brazil this work contributes for the continuous increasing of the customers satisfaction and the profitability of the company.

Plants and arthropods: friends or foes ?

NARCIS (Netherlands)

Kant, M.; Williams, M.

2011-01-01

Plants are the most abundant terrestrial food sources, and arthropods (insects and arachnids) their most abundant consumers. For this reason plants are heavily defended by thorns, thick impervious coverings, and extraordinary toxins. However, plant fitness also depends upon alliances with arthropods

About soil cover heterogeneity of agricultural research stations' experimental fields

Science.gov (United States)

Rannik, Kaire; Kõlli, Raimo; Kukk, Liia

2013-04-01

Depending on local pedo-ecological conditions (topography, (geo) diversity of soil parent material, meteorological conditions) the patterns of soil cover and plant cover determined by soils are very diverse. Formed in the course of soil-plant mutual relationship, the natural ecosystems are always influenced to certain extent by the other local soil forming conditions or they are site specific. The agricultural land use or the formation of agro-ecosystems depends foremost on the suitability of soils for the cultivation of feed and food crops. As a rule, the most fertile or the best soils of the area, which do not present any or present as little as possible constraints for agricultural land use, are selected for this purpose. Compared with conventional field soils, the requirements for the experimental fields' soil cover quality are much higher. Experimental area soils and soil cover composition should correspond to local pedo-ecological conditions and, in addition to that, represent the soil types dominating in the region, whereas the fields should be as homogeneous as possible. The soil cover heterogeneity of seven arable land blocks of three research stations (Jõgeva, Kuusiku and Olustvere) was studied 1) by examining the large scale (1:10 000) digital soil map (available via the internet), and 2) by field researches using the transect method. The stages of soils litho-genetic and moisture heterogeneities were estimated by using the Estonian normal soils matrix, however, the heterogeneity of top- and subsoil texture by using the soil texture matrix. The quality and variability of experimental fields' soils humus status, was studied more thoroughly from the aspect of humus concentration (g kg-1), humus cover thickness (cm) and humus stocks (Mg ha-1). The soil cover of Jõgeva experimental area, which presents an accumulative drumlin landscape (formed during the last glacial period), consist from loamy Luvisols and associated to this Cambisols. In Kuusiku area

Topography Mediates the Influence of Cover Crops on Soil Nitrate Levels in Row Crop Agricultural Systems

OpenAIRE

Ladoni, Moslem; Kravchenko, Alexandra N.; Robertson, G. Phillip

2015-01-01

Supplying adequate amounts of soil N for plant growth during the growing season and across large agricultural fields is a challenge for conservational agricultural systems with cover crops. Knowledge about cover crop effects on N comes mostly from small, flat research plots and performance of cover crops across topographically diverse agricultural land is poorly understood. Our objective was to assess effects of both leguminous (red clover) and non-leguminous (winter rye) cover crops on poten...

Performance of Evapotranspirative Covers Under Enhanced Precipitation: Preliminary Data

International Nuclear Information System (INIS)

David C. Anderson; Lloyd T. Desotell; David B. Hudson; Gregory J. Shott; Vefa Yucel

2007-01-01

Since January 2001, drainage lysimeter studies have been conducted at Yucca Flat, on the Nevada Test Site, in support of an evapotranspirative cover design. Yucca Flat has an arid climate with average precipitation of 16.5 cm annually. The facility consists of six drainage lysimeters 3 m in diameter, 2.4 m deep, and backfilled with a single layer of native soil. The bottom of each lysimeter is sealed and equipped with a small drain that enables direct measurement of saturated drainage. Each lysimeter has eight time-domain reflectometer probes to measure moisture content-depth profiles paired with eight heat-dissipation probes to measure soil-water potential depth profiles. Sensors are connected to dataloggers which are remotely accessed via a phone line. The six lysimeters have three different surface treatments: two are bare-soil; two were revegetated with native species (primarily shadscale, winterfat, ephedra, and Indian rice grass); and two were allowed to revegetate naturally with such species as Russian thistle, halogeton, tumblemustard and cheatgrass. Beginning in October 2003, one half of the paired cover treatments (one bare soil, one invader species, and one native species) were irrigated with an amount of water equal to two times the natural precipitation to achieve a three times natural precipitation treatment. From October 2003 through December 2005, all lysimeters received 52.8 cm precipitation, and the four irrigated lysimeters received an extra 105.6 cm of irrigation. No drainage has occurred from any of the nonirrigated lysimeters, but moisture has accumulated at the bottom of the bare-soil lysimeter and the native-plant lysimeter. All irrigated lysimeters had some drainage. The irrigated baresoil lysimeter had 48.3 cm of drainage or 26.4 percent of the combined precipitation and applied irrigation for the entire monitoring record. The irrigated invader species lysimeter had 5.8 cm of drainage, about 3.2 percent of the combined precipitation and

Sensitive Electrochemical Determination of Gallic Acid: Application in Estimation of Total Polyphenols in Plant Samples

Directory of Open Access Journals (Sweden)

Mohammad Ali Sheikh-Mohseni

2016-12-01

Full Text Available A modified electrode was prepared by modification of the carbon paste electrode (CPE with graphene nano-sheets. The fabricated modified electrode exhibited an electrocatalytic activity toward gallic acid (GA oxidation because of good conductivity, low electron transfer resistance and catalytic effect. The graphene modified CPE had a lower overvoltage and enhanced electrical current respect to the bare CPE for the oxidation of GA. The oxidation potential of GA decreased more than 210 mV by the modified electrode. The modified electrode responded to the GA in the concentration range of 3.0 × 10-5-1.5 × 10-4 M with high sensitivity by the technique of differential pulse voltammetry. Also, detection limit of 1.1 × 10-7 M was obtained by this modified electrode for GA. This electrode was used for the successful determination of GA in plant samples. Therefore, the content of total polyphenols in plant samples can be determined by the proposed modified electrode based on the concentration of GA in the sample.

Modeling Operating Modes during Plant Life Cycle

DEFF Research Database (Denmark)

Jørgensen, Sten Bay; Lind, Morten

2012-01-01

Modelling process plants during normal operation requires a set a basic assumptions to define the desired functionalities which lead to fullfillment of the operational goal(-s) for the plant. However during during start-up and shut down as well as during batch operation an ensemble of interrelated...... modes are required to cover the whole operational window of a processs plant including intermediary operating modes. Development of such an model ensemble for a plant would constitute a systematic way of defining the possible plant operating modes and thus provide a platform for also defining a set...... of candidate control structures. The present contribution focuses on development of a model ensemble for a plant with an illustartive example for a bioreactor. Starting from a functional model a process plant may be conceptually designed and qualitative operating models may be developed to cover the different...

Fully covered stents versus partially covered stents for palliative treatment of esophageal cancer: Is there a difference?

Science.gov (United States)

Alonso Lárraga, J O; Flores Carmona, D Y; Hernández Guerrero, A; Ramírez Solís, M E; de la Mora Levy, J G; Sánchez Del Monte, J C

2018-02-26

Malignant dysphagia is difficulty swallowing resulting from esophageal obstruction due to cancer. The goal of palliative treatment is to reduce the dysphagia and improve oral dietary intake. Self-expandable metallic stents are the current treatment of choice, given that they enable the immediate restoration of oral intake. The aim of the present study was to describe the results of using totally covered and partially covered esophageal stents for palliating esophageal cancer. A retrospective study was conducted on patients with inoperable esophageal cancer treated with self-expandable metallic stents. The 2 groups formed were: group A, which consisted of patients with a fully covered self-expandable stent (SX-ELLA ® ), and group B, which was made up of patients with a partially covered self-expandable stent (Ultraflex ® ). Of the 69-patient total, 50 were included in the study. Group A had 19 men and 2 women and their mean age was 63.6 years (range 41-84). Technical success was achieved in 100% (n=21) of the cases and clinical success in 90.4% (n=19). Group B had 24 men and 5 women and their mean age was 67.5 years (range 43-92). Technical success was achieved in 100% (n=29) of the cases and clinical success in 89.6% (n=26). Complications were similar in both groups (33.3 vs. 51.7%). There was no difference between the 2 types of stent for the palliative treatment of esophageal cancer with respect to technical success, clinical success, or complications. Copyright © 2018 Asociación Mexicana de Gastroenterología. Publicado por Masson Doyma México S.A. All rights reserved.

Evaluation of automated analysis of 15N and total N in plant material and soil

DEFF Research Database (Denmark)

Jensen, E.S.

1991-01-01

Simultaneous determination of N-15 and total N using an automated nitrogen analyser interfaced to a continuous-flow isotope ratio mass spectrometer (ANA-MS method) was evaluated. The coefficient of variation (CV) of repeated analyses of homogeneous standards and samples at natural abundance...... was lower than 0.1%. The CV of repeated analyses of N-15-labelled plant material and soil samples varied between 0.3% and 1.1%. The reproducibility of repeated total N analyses using the automated method was comparable to results obtained with a semi-micro Kjeldahl procedure. However, the automated method...... analysis showed that the recovery of inorganic N in the NH3 trap was lower when the N was diffused from water than from 2 M KCl. The results also indicated that different proportions of the NO3- and the NH4+ in aqueous solution were recovered in the trap after combined diffusion. The method is most suited...

Performance evaluation of intermediate cover soil barrier for removal of heavy metals in landfill leachate.

Science.gov (United States)

Suzuki, Kazuyuki; Anegawa, Aya; Endo, Kazuto; Yamada, Masato; Ono, Yusaku; Ono, Yoshiro

2008-11-01

This pilot-scale study evaluated the use of intermediate cover soil barriers for removing heavy metals in leachate generated from test cells for co-disposed fly ash from municipal solid waste incinerators, ash melting plants, and shredder residue. Cover soil barriers were mixtures of Andisol (volcanic ash soil), waste iron powder, (grinder dust waste from iron foundries), and slag fragments. The cover soil barriers were installed in the test cells' bottom layer. Sorption/desorption is an important process in cover soil bottom barrier for removal of heavy metals in landfill leachate. Salt concentrations such as those of Na, K, and Ca in leachate were extremely high (often greater than 30 gL(-1)) because of high salt content in fly ash from ash melting plants. Concentrations of all heavy metals (nickel, manganese, copper, zinc, lead, and cadmium) in test cell leachates with a cover soil barrier were lower than those of the test cell without a cover soil barrier and were mostly below the discharge limit, probably because of dilution caused by the amount of leachate and heavy metal removal by the cover soil barrier. The cover soil barriers' heavy metal removal efficiency was calculated. About 50% of copper, nickel, and manganese were removed. About 20% of the zinc and boron were removed, but lead and cadmium were removed only slightly. Based on results of calculation of the Langelier saturation index and analyses of core samples, the reactivity of the cover soil barrier apparently decreases because of calcium carbonate precipitation on the cover soil barriers' surfaces.

Antimalarial Activity of Plant Metabolites.

Science.gov (United States)

Pan, Wen-Hui; Xu, Xin-Ya; Shi, Ni; Tsang, Siu Wai; Zhang, Hong-Jie

2018-05-06

Malaria, as a major global health problem, continues to affect a large number of people each year, especially those in developing countries. Effective drug discovery is still one of the main efforts to control malaria. As natural products are still considered as a key source for discovery and development of therapeutic agents, we have evaluated more than 2000 plant extracts against Plasmodium falciparum . As a result, we discovered dozens of plant leads that displayed antimalarial activity. Our phytochemical study of some of these plant extracts led to the identification of several potent antimalarial compounds. The prior comprehensive review article entitled “Antimalarial activity of plant metabolites” by Schwikkard and Van Heerden (2002) reported structures of plant-derived compounds with antiplasmodial activity and covered literature up to the year 2000. As a continuation of this effort, the present review covers the antimalarial compounds isolated from plants, including marine plants, reported in the literature from 2001 to the end of 2017. During the span of the last 17 years, 175 antiplasmodial compounds were discovered from plants. These active compounds are organized in our review article according to their plant families. In addition, we also include ethnobotanical information of the antimalarial plants discussed.

Antimalarial Activity of Plant Metabolites

Directory of Open Access Journals (Sweden)

Wen-Hui Pan

2018-05-01

Full Text Available Malaria, as a major global health problem, continues to affect a large number of people each year, especially those in developing countries. Effective drug discovery is still one of the main efforts to control malaria. As natural products are still considered as a key source for discovery and development of therapeutic agents, we have evaluated more than 2000 plant extracts against Plasmodium falciparum. As a result, we discovered dozens of plant leads that displayed antimalarial activity. Our phytochemical study of some of these plant extracts led to the identification of several potent antimalarial compounds. The prior comprehensive review article entitled “Antimalarial activity of plant metabolites” by Schwikkard and Van Heerden (2002 reported structures of plant-derived compounds with antiplasmodial activity and covered literature up to the year 2000. As a continuation of this effort, the present review covers the antimalarial compounds isolated from plants, including marine plants, reported in the literature from 2001 to the end of 2017. During the span of the last 17 years, 175 antiplasmodial compounds were discovered from plants. These active compounds are organized in our review article according to their plant families. In addition, we also include ethnobotanical information of the antimalarial plants discussed.

DEPENDENCE OF GRASS COVER TAXONOMIC AND ECOLOGICAL STRUCTURE ON THE ANTHROPOGENIC IMPACT IN FOREST ECOSYSTEMS

Directory of Open Access Journals (Sweden)

N. V. Miroshnik

2016-01-01

Full Text Available Pine forests Chigirinsky Bor grow on fresh sod-podzolic soils formed on ancient alluvial deposits. Pine forests are characterized by stringent moisture regimes and constantly suffer from lack of productive moisture in soil.  Industrial development of Cherkasy in 60th years of ХХ century leaded air pollution and emissions of SO2, NOx, NH3, and dust. This contributed to significant negative influence on the surrounding forest ecosystems from enterprises of  Cherkassy industrial agglomeration. The grass cover in pine stands of Chigirinsky Bor transforms into xerophytic grasses and ruderal communities under the impact of negative biotic and abiotic factors. They are namely the anthropogenic violation of forest conditions, stands decline, recreational and industrial tree crowns understocking, xerophytic and heliophytic transformations of forest conditions. All the above mentioned caused strong ruderal and adventive transformation of grass cover. We registered the changes in nitrophilous plant spread regards the Cherkasy industrial agglomeration approaching which emits toxic with nitrogen-containing gases. Adventive and other non-forest species displace ferns and mosses, the ratio of ecomorfs is also changes due to increase of the quantity and development activation of annuals, xerophytic, ruderal, and nitrofil plants. The Asteraceae/Brassicaceae 3:1 ratio indicates significant anthropogenic violations in the region. We fixed the xerophytic, ruderal, and adventive transformation of grass cover in forest ecosystems. It is also founded the tendency of expanding the fraction of mesophilic plant species due to alterations in water regime (creation of Kremenchug reservoir and draining of floodplain Tyasmyn. When approaching the Cherkasy industrial agglomeration the grass cover degradation is clearly observed on the environmental profile. All this causes the forest ecosystem degradation and gradual loss of forest vegetation typical characteristics. We

Emergency control centers for nuclear power plants

International Nuclear Information System (INIS)

Anon.

1979-01-01

Guidance is provided for the development and implementation of emergency control centers for nuclear power plants, including nuclear plant control room, nuclear plant company headquarters, emergency control center, and nuclear plant alternate emergency control center. Requirements and recommendations are presented for the mission, communications, instrumentation and equipment associated with each type of control center. Decisional aids, manning requirements and resources are also given; the decision aids cover both the accident assessment and protective action areas. Both normal and alternate means of communications are considered. Off-site emergency control centers, although not covered in the strict sense by this standard, are considered in an appendix

Goods and services provided by native plants in desert ecosystems: Examples from the northwestern coastal desert of Egypt

Directory of Open Access Journals (Sweden)

Laila M. Bidak

2015-01-01

Full Text Available About one third of the earth’s land surface is covered by deserts that have low and variable rainfall, nutrient-poor soils, and little vegetation cover. Here, we focus on the goods and services offered by desert ecosystems using the northwestern coastal desert of Egypt extending from Burg El-Arab to El-Salloum as an example. We conducted field surveys and collected other data to identify the goods services and provided by native plant species. A total of 322 native plant species were compiled. The direct services provided by these native plants included sources of food, medicine, and energy; indirect vegetation services included promotion of biodiversity, water storage, and soil fertility. The plant diversity in this ecosystem provided economic service benefits, such as sources of fodder, fuel-wood, and traditional medicinal plants. Changes in land use and recent ill-managed human activities may influence the availability of these services and strongly impact biodiversity and habitat availability. Although deserts are fragile and support low levels of productivity, they provide a variety of goods and services whose continuing availability is contingent upon the adoption of rational land management practices.

Effect of slope and plant cover on run-off, soil loss and water use ...

African Journals Online (AJOL)

An average of 6,2t/ha soil loss and 80,6% run-off of the amount of water applied occurred from the pioneer veld (0,7% basal cover) on the steepest slope. In all the successional stages more run-off and less soil loss occurred from wet soil than from dry soil. Significant (P<0,01) relationships between basal and canopy cover ...

Covering of the electric power service

International Nuclear Information System (INIS)

Unidad de Planeacion Minero Energetica, UPME

2000-01-01

In this article it is sought to deepen more in the topic of the covering of the electric power service, especially in the related with the mechanisms that could facilitate their amplification. In the new market outline, in the one that the participation of the agents is encouraged in all the activities of the chain of services in which the state is not direct lender of the same one, it is confused the form like a covering will be achieved that is of agreement with the goals that intend in the national plan of development and in the sub sectorial plans. Although the rules of the market one comes consolidating, the process of linking of the private capital, especially in the distribution activity, it evidences the importance of to settle down and to define responsibilities and explicit mechanisms in the topic of expansion of the covering. A first interpretation of the ruled indicates the obligation of the state of extending the covering to 100% and of assuming the projects that don't undertake the matters. This would be the reading from the traditional mentality. However, the regulation of you public services of electricity don't demand a total covering, but rather it covers to the users that have the capacity to assume, with their own resources, the efficient costs of benefit. The service will also be lent to residential users that don't have payment capacity, when there are contribution resources or fiscal resources for subsidiary

Variability and trend of diurnal temperature range in China and their relationship to total cloud cover and sunshine duration

Energy Technology Data Exchange (ETDEWEB)

Xia, X. [Chinese Academy of Sciences, Beijing (China). LAGEO

2013-07-01

This study aims to investigate the effect of total cloud cover (TCC) and sunshine duration (SSD) in the variation of diurnal temperature range (DTR) in China during 1954-2009. As expected, the inter-annual variation of DTR was mainly determined by TCC. Analysis of trends of 30- year moving windows of DTR and TCC time series showed that TCC changes could account for that of DTR in some cases. However, TCC decreased during 1954-2009, which did not support DTR reduction across China. DTRs under sky conditions such as clear, cloudy and overcast showed nearly the same decreasing rate that completely accounted for the overall DTR reduction. Nevertheless, correlation between SSD and DTR was weak and not significant under clear sky conditions in which aerosol direct radiative effect should be dominant. Furthermore, 30-60% of DTR reduction was associated with DTR decrease under overcast conditions in south China. This implies that aerosol direct radiative effect appears not to be one of the main factors determining long-term changes in DTR in China. (orig.)

Optimum Vegetation Conditions for Successful Establishment of Planted Eastern White Pine (Pinus strobus L.

Directory of Open Access Journals (Sweden)

Douglas G. Pitt

2016-08-01

Full Text Available The 10th-growing season performance of planted eastern white pine (Pinus strobus L. seedlings was evaluated in response to herbaceous and woody vegetation control treatments within a clearcut and two variants of the uniform shelterwood regeneration system (single vs. multiple future removal cuts. Herbaceous vegetation control involved the suppression of grasses, forbs, ferns and low shrubs for the first 2 or 4 growing seasons after planting. Deciduous woody vegetation control treatments, conducted in combination with the herbaceous treatments within a response-surface design, involved the permanent removal of all tall shrubs and deciduous trees at the time of planting, at the end of the 2nd or 5th growing seasons, or not at all. In general, the average size of planted pine was related positively to the duration of herbaceous vegetation control and negatively to delays in woody control. White pine weevil (Pissodes strobi Peck altered these trends, reducing the height of pine on plots with little or no overtopping deciduous woody vegetation or mature tree cover. Where natural pine regeneration occurred on these plots, growth was similar but subordinate to the planted pine. Data from the three sites indicate that at least 60% of planted pine may be expected to reach an age-10 height target of 2.5 m when overtopping cover (residual overstory + regenerating deciduous is managed at approximately 65% ± 10%, and total herbaceous cover is suppressed to levels not exceeding 50% in the first five years. On productive sites, this combination may be difficult to achieve in a clearcut, and requires fairly rigorous vegetation management in shelterwood regeneration systems. Currently, synthetic herbicides offer the only affordable and effective means of achieving such vegetation control.

Índice de cobertura vegetal pela cultura do milho no período de chuvas intensas no sul de Minas Gerais Plant cover index in the period of intensive rainfall for corn crop at south of Minas Gerais state, Brazil

Directory of Open Access Journals (Sweden)

Fabiana Silva de Souza

2010-04-01

Full Text Available A cobertura vegetal é a defesa natural do solo contra a erosão hídrica. Nos modelos de estimativas de perdas de solo, o efeito da cobertura vegetal na interceptação da energia cinética da chuva é a variável chave na modelagem do processo erosivo. Assim sendo, objetivou-se avaliar a eficiência da cobertura vegetal, proporcionada pela cultura do milho, e suas relações com os atributos fitotécnicos desta cultura para alguns híbridos. O estudo foi realizado no campo demonstrativo de híbridos de milho da Universidade Federal de Lavras, localizada no município de Lavras, MG. Para determinação da cobertura vegetal utilizou-se um aparato que consiste em uma estrutura horizontal, contendo orifícios para visualização dos pontos com cobertura e sem cobertura vegetal, sendo as leituras feitas de forma aleatória e transversalmente às linhas da cultura. Os atributos fitotécnicos avaliados foram altura da planta, estande, matéria seca e produção de grãos. Diante dos resultados pode-se concluir que o maior índice de cobertura vegetal foi observado para os híbridos de milho P 30F33, P 30F90, P 3021, STRIKE, FORT, VALENT, UFLA 2001, UFLA 2004, CO 32, D 8480, D 8420 DKB 333B, DKB 440, evidenciando boa qualidade como planta protetora do solo. No período de maior ocorrência de chuvas, na região sul de Minas Gerais, a cultura do milho pode minimizar o efeito do processo erosivo. A produção de matéria seca relacionou-se bem com o índice de cobertura vegetal, podendo ser um indicativo quanto à proteção do solo.The plant cover is a natural protection of soil against water erosion. In estimative models of soil loss, the effect of plant cover in the interception of rainfall kinetic energy is the key variable in the modeling of the erosive process. Thus, the aim of this work is to evaluate the efficiency of the plant cover provided by the corn crop and their relations with the phytotechnical attributes of this crop for its respective

Plant walkdown

International Nuclear Information System (INIS)

Kostov, M.

2000-01-01

This report covers the following: preparatory steps for performing plant walk-down; the objective of the first plant walk-down; plant walk-down procedures; earthquake screening evaluation; walk-down documentation; second plant walk-down. The following objectives concerning the plant walk-down(s) were achieved. The plant system configuration is verified in order to proceed with event tree and fault tree analyses. Systems interactions, other types of dependencies or plant unique features are identified. he safety related components that are judged to generically possess high capacities (i.e., larger than the earthquake review level) have been verified to contain no weaknesses. Further analyses needed to establish the capacities of remaining safety-related components are identified and necessary field data are obtained. Information on components is obtained to assist in HCLPF (fragility) evaluation and peer review of the seismic margin study

Infestation of froghopper nymphs changes the amounts of total phenolics in sugarcane

Directory of Open Access Journals (Sweden)

Silva Rafael José Navas da

2005-01-01

Full Text Available The increased rate of sugarcane harvest without previous burn has provided a very favorable environment to the froghopper Mahanarva fimbriolata (Stal, 1854, with high moisture and low temperature variation. Few works have studied the response of sugarcane to this pest, so little is known about resistant cultivars. Plant phenolics are widely studied compounds because of their known antiherbivore effect. This research aims to determine if the attack of M. fimbriolata nymphs stimulates the accumulation of total phenolics in sugarcane. The experiment was carried out in greenhouse and arranged in completely randomized design, in a 3 X 2 X 4 factorial with three replications. Second instar nymphs of M. fimbriolata were infested at the following rates: control, 2-4 and 4-8 nymphs per pot (first-second infestations, respectively. Pots were covered with nylon net and monitored daily to isolate the effect of leaf sucking adults. Leaf and root samples were collected and kept frozen in liquid nitrogen until analyses. Infested plants showed higher levels of phenolics in both root and leaf tissues. In roots, the cultivar SP80-1816 accumulated more phenolic compounds in response to the infestation of M. fimbriolata. On the other hand, higher levels were found in leaves and roots of control plants of SP86-42, which might be an indication of a non-preference mechanism. The increase of total phenolics in sugarcane infested with root-sucking froghopper nymphs does not seem to be useful to detect the resistance to this pest.

Cover Crop Species and Management Influence Predatory Arthropods and Predation in an Organically Managed, Reduced-Tillage Cropping System.

Science.gov (United States)

Rivers, Ariel N; Mullen, Christina A; Barbercheck, Mary E

2018-04-05

Agricultural practices affect arthropod communities and, therefore, have the potential to influence the activities of arthropods. We evaluated the effect of cover crop species and termination timing on the activity of ground-dwelling predatory arthropods in a corn-soybean-wheat rotation in transition to organic production in Pennsylvania, United States. We compared two cover crop treatments: 1) hairy vetch (Vicia villosa Roth) planted together with triticale (×Triticosecale Wittmack) after wheat harvest, and 2) cereal rye (Secale cereale Linnaeus) planted after corn harvest. We terminated the cover crops in the spring with a roller-crimper on three dates (early, middle, and late) based on cover crop phenology and standard practices for cash crop planting in our area. We characterized the ground-dwelling arthropod community using pitfall traps and assessed relative predation using sentinel assays with live greater waxworm larvae (Galleria mellonella Fabricius). The activity density of predatory arthropods was significantly higher in the hairy vetch and triticale treatments than in cereal rye treatments. Hairy vetch and triticale favored the predator groups Araneae, Opiliones, Staphylinidae, and Carabidae. Specific taxa were associated with cover crop condition (e.g., live or dead) and termination dates. Certain variables were positively or negatively associated with the relative predation on sentinel prey, depending on cover crop treatment and stage, including the presence of predatory arthropods and various habitat measurements. Our results suggest that management of a cover crop by roller-crimper at specific times in the growing season affects predator activity density and community composition. Terminating cover crops with a roller-crimper can conserve generalist predators.

Estimating cotton canopy ground cover from remotely sensed scene reflectance

International Nuclear Information System (INIS)

Maas, S.J.

1998-01-01

Many agricultural applications require spatially distributed information on growth-related crop characteristics that could be supplied through aircraft or satellite remote sensing. A study was conducted to develop and test a methodology for estimating plant canopy ground cover for cotton (Gossypium hirsutum L.) from scene reflectance. Previous studies indicated that a relatively simple relationship between ground cover and scene reflectance could be developed based on linear mixture modeling. Theoretical analysis indicated that the effects of shadows in the scene could be compensated for by averaging the results obtained using scene reflectance in the red and near-infrared wavelengths. The methodology was tested using field data collected over several years from cotton test plots in Texas and California. Results of the study appear to verify the utility of this approach. Since the methodology relies on information that can be obtained solely through remote sensing, it would be particularly useful in applications where other field information, such as plant size, row spacing, and row orientation, is unavailable

Biochemistry, proteomics and phosphoproteomics of plant mitochondria from non-photosynthetic cells

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Jesper Foged Havelund

2013-03-01

Full Text Available Mitochondria fulfill some basic roles in all plant cells. They supply the cell with energy in the form of ATP and reducing equivalents (NAD(PH and they provide the cell with intermediates for a range of biosynthetic pathways. In addition to this, mitochondria contribute to a number of specialized functions depending on the tissue and cell type, as well as environmental conditions. We will here review the biochemistry and proteomics of mitochondria from non-green cells and organs, which differ from those of photosynthetic organs in a number of respects. We will briefly cover purification of mitochondria and general biochemical properties such as oxidative phosphorylation. We will then mention a few adaptive properties in response to water stress, seed maturation and germination and the ability to function under hypoxic conditions. The discussion will mainly focus on Arabidopsis cell cultures, etiolated germinating rice seedlings and potato tubers as model plants. It will cover the general proteome as well as the posttranslational modification protein phosphorylation. To date 64 phosphorylated mitochondrial proteins with a total of 103 phosphorylation sites have been identified.

Availability of thermal power plants 1985-1994. 24. ed.

International Nuclear Information System (INIS)

Nitsch, D.; Schmitz, H.

1995-01-01

The survey in hand is the 24th statistical report in the series commenced in 1970. It covers the ten-year period from 1985 through 1994 and presents availability data of 349 power plants in Germany and abroad, representing approx. 99.000 MW and a total of 3.500 years of operating experience. Data are presented on fossil-fuel units, units with a combined gas/steam cycle, nuclear power plants, and gas turbines. The fossil-fuel units are broken down by unit size, years of operation, fuel, type of combustion (dry, melt), and design type (monoblock and duoblock, subcritical and supercritical systems). Nuclear power plants are arranged by type of reactor (PWR, BWR), unit size, and years of operation. Combined-cycle power plants are listed separately due to their various technical design concepts. The gas turbine data are arranged by years of operation. Apart from availability and utilisation data of gas turbines, there are data on event reliability and the number of successful or unsuccessful starts. In general, data for all plants and systems included are given first whenever appropriate, the data for the German plants following in second place. Performance data are gross values measured at generator terminals and, just as the number of plants, are end-of-the-year figures. (orig./GL) [de

impacts of rainfall and forest cover change on runoff in small ...

African Journals Online (AJOL)

the relationship between rainfall and runoff in the two catchments has changed. Furthermore .... The monthly rainfall data for Namadzi catchment that was used in this .... land cover change with a big jump of forest planted after the 1990s. Fig.

Biocompatibility of a new device of self-expandable covered and non-covered tracheal stent: comparative study in rats

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Olavo Ribeiro Rodrigues

2013-01-01

Full Text Available PURPOSE: To investigate the compatibility of a new model of self-expandable tracheal stent in rats. METHODS: A new device of polyurethane covered and non - covered stent was placed in the trachea of Wistar rats. Animals were distributed in two groups: the polyurethane covered and non-covered group. Macroscopic parameters included position within the tracheal lumen, adherence to the mucosa, degree of dilatation, permeability and internal diameter. Microscopic findings evaluated were: incorporation, inflammatory activity, granulation tissue and epithelial revetment injuries. The observation follow-up was six weeks. All parameters were quantified based on determined score values. Incorporation of the stents was evaluated based on the observation if the stent was fixed into the trachea or if it could be removed. Degree of dilatation was performed by external diameter measurements. Granulation tissue was evaluated by measurements of height of the tissue growing into the tracheal lumen. RESULTS: 100% of non-covered stents had total attachment to mucosa and 100% of polyurethane covered type had adherence only. Regarding dilatation, granulation tissue, inflammatory activity and internal diameter measurements, there were no significant differences between the groups. Pathological tracheal wall injuries were present in both groups. CONCLUSION: Both models of stent demonstrated biocompatibility with the trachea. Rats are suitable for an experimental model of tracheal stent study.

Increased Risk of Insect Injury to Corn Following Rye Cover Crop.

Science.gov (United States)

Dunbar, Mike W; O'Neal, Matthew E; Gassmann, Aaron J

2016-08-01

Decreased pest pressure is sometimes associated with more diverse agroecosystems, including the addition of a rye cover crop (Secale cereale L.). However, not all pests respond similarly to greater vegetational diversity. Polyphagous pests, such as true armyworm (Mythimna unipuncta Haworth), black cutworm (Agrotis ipsilon Hufnagel), and common stalk borer (Papaipema nebris Guenee), whose host range includes rye have the potential to cause injury to crops following a rye cover crop. The objectives of this study were to compare the abundance of early-season insect pests and injury to corn (Zea mays L.) from fields with and without a rye cover crop on commercial farms. Fields were sampled weekly to quantify adult and larval pests and feeding injury to corn plants from mid-April until corn reached V8 stage, during 2014 and 2015. Measurements within fields were collected along transects that extended perpendicularly from field edges into the interior of cornfields. Adult true armyworm and adult black cutworm were captured around all cornfields, but most lepidopteran larvae captured within cornfields were true armyworm and common stalk borer. Cornfields with a rye cover crop had significantly greater abundance of true armyworm and greater proportion of injured corn. Both true armyworm abundance and feeding injury were significantly greater in the interior of cornfields with rye. Common stalk borer abundance did not differ between cornfields with or without rye cover. Farmers planting corn following a rye cover crop should be aware of the potential for increased presence of true armyworm and for greater injury to corn. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

CORINE land cover and floristic variation in a Mediterranean wetland.

Science.gov (United States)

Giallonardo, Tommaso; Landi, Marco; Frignani, Flavio; Geri, Francesco; Lastrucci, Lorenzo; Angiolini, Claudia

2011-11-01

The aims of the present study were to: (1) investigate whether CORINE land cover classes reflect significant differences in floristic composition, using a very detailed CORINE land cover map (scale 1:5000); (2) decompose the relationships between floristic assemblages and three groups of explanatory variables (CORINE land cover classes, environmental characteristics and spatial structure) into unique and interactive components. Stratified sampling was used to select a set of 100-m(2) plots in each land cover class identified in the semi-natural wetland surrounding a lake in central Italy. The following six classes were considered: stable meadows, deciduous oak dominated woods, hygrophilous broadleaf dominated woods, heaths and shrublands, inland swamps, canals or watercourses. The relationship between land cover classes and floristic composition was tested using several statistical techniques in order to determine whether the results remained consistent with different procedures. The variation partitioning approach was applied to identify the relative importance of three groups of explanatory variables in relation to floristic variation. The most important predictor was land cover, which explained 20.7% of the variation in plant distribution, although the hypothesis that each land cover class could be associated with a particular floristic pattern was not verified. Multi Response Permutation Analysis did not indicate a strong floristic separability between land cover classes and only 9.5% of species showed a significant indicator value for a specific land cover class. We suggest that land cover classes linked with hygrophilous and herbaceous communities in a wetland may have floristic patterns that vary with fine scale and are not compatible with a land cover map.

Effective Phytoextraction of Cadmium (Cd) with Increasing Concentration of Total Phenolics and Free Proline in Cannabis sativa (L) Plant Under Various Treatments of Fertilizers, Plant Growth Regulators and Sodium Salt.

Science.gov (United States)

Ahmad, Ayaz; Hadi, Fazal; Ali, Nasir

2015-01-01

The comparative effect of fertilizers (NPK), plant growth regulators (GA3, IAA, Zeatin) and sodium chloride (NaCl) on Cd phytoaccumulation, proline and phenolics production in Cannabis sativa was evaluated. Proline and phenolices were correlated with Cd contents in plant. Cd significantly reduced the plant growth. Fertilizers application (in combination) most significantly increased the growth (19 cm root and 47 cm shoot) on Cd contaminated soil. All treatments increased the Cd contents in plant tissues. This increase was highly significant in fertilizers treated plants (1101, 121 and 544 ppm in roots, stem and leaves respectively). Significantly positive correlation was found between Cd concentration and dry biomass of root (R2=0.7511) and leaves (R2=0.5524). All treatments significantly increased the proline and total phenolics and maximum was recorded in NaCl treated plants followed by fertilizers. Proline was higher in roots while phenolics in leaves. The correlation between proline and phenolics was positive in leaf (R2=0.8439) and root (R2=0.5191). Proline and phenolics showed positive correlation with Cd concentration in plant. Conclusively, fertilizers in combination seem to be the better option for Cd phytoextraction. Further investigation is suggested to study the role of phenolics and proline in Cd phytoextraction.

A study of the performance of a reclamation soil cover placed over an oilsands coke deposit

Energy Technology Data Exchange (ETDEWEB)

Fenske, D.S.; Barbour, S.L. [Saskatchewan Univ., Saskatoon, SK (Canada). Dept. of Civil Engineering; Qualizza, C. [Syncrude Canada Ltd., Fort McMurray, AB (Canada)

2006-07-01

Coke is a solid, carbonaceous residue that forms during the cracking of high-boiling point distillates and is one of the by-products of petroleum extraction from oilsands. Coke is known as a possible future energy source and therefore, must be stored within the reclaimed landscape in a form that allows it to be recovered. In addition, it also could be used as a low-density capping material over soft tailings. This paper presented the results of a study that examined the effects of coke in the environment. The study involved construction of two small instrumented watersheds at Syncrude Canada's Mildred Lake Settling Basin. Preliminary field data, highlighting the moisture dynamics within the covers and the underlying coke were discussed. Sand tailings underlie the hydraulically placed coke deposit. Overlying the coke were two different reclamation soil covers constructed of a peat/mineral mix over glacial or glacial lacustrine soils. Placing the finer textured soil cover over coarser grained coke produced a textural or capillary break which enhanced moisture storage for plant use while minimizing deep percolation of infiltrating water. The site has been instrumented with a meteorological station; automated soil stations to monitor suction, water content and temperature through the cover profile; lysimeters to collect net percolation; access tubes for water content monitoring; gas sampling points at depth in the coke; and standpipe piezometers to monitor water chemistry and total head in the coke at depth. 10 refs., 2 tabs., 16 figs.

PORE SIZE DISTRIBUTION AND SOIL HYDRO PHYSICAL PROPERTIES UNDER DIFFERENT TILLAGE PRACTICES AND COVER CROPS IN A TYPIC HAPLUSULT IN NORTHERN NIGERIA

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Halima Mohammed Lawal

2017-05-01

Full Text Available Tillage practices influence soil physical, chemical and biological qualities which in-turn alters plant growth and crop yield. In the Northern Guinea Savanna (NGS ecological zone of Nigeria, agricultural production is mainly constrained by low soil nutrient and water holding capacity, it is therefore, imperative to develop appropriate management practices that will give optimal soil hydro-physical properties for proper plant growth, effective soil and water management and environmental conservation. This study investigated the effect of three tillage practices (no till, reduced till and conventional till and four cover crops (Centrosema pascuorum, Macrotyloma uniflorum, Cucurbita maxima and Glyine max and a bare/control (no cover crop on some soil physical properties of a Typic Haplusult during the rainy seasons of 2011, 2012 and 2013 in Samaru, NGS ecological zone of Nigeria. The field trials were laid out in a split plot arrangement with tillage practices in the main plots and cover crops in the subplots, all treatments were replicated three times. Auger and core soil samples were collected at the end of each cropping season each year in three replicates from each treatment plot at four depths (0-5, 5-10, 10-15 and 15-20 cm. Particle size distribution, bulk density, total pore volume and water retention at various soil matric potentials were determined using standard methods. Data obtained were compared with optimum values and fitted into a RETC computer code for quantifying soil hydraulic behavior and physical quality. Results showed that different tillage practices had varied effect on soil physical properties. No-till had the highest water holding capacity at most suction points evaluated, it had 4.3 % and 12.9 % more soil moisture than the reduced till  and conventionally tilled systems across all matric potentials while Centrosema pascuorum (3.1% and Cucurbita maxima (5.5% were best among evaluated cover crops in retaining soil moisture

Winter cover crops on processing tomato yield, quality, pest pressure, nitrogen availability, and profit margins.

Science.gov (United States)

Belfry, Kimberly D; Trueman, Cheryl; Vyn, Richard J; Loewen, Steven A; Van Eerd, Laura L

2017-01-01

Much of cover crop research to date focuses on key indicators of impact without considering the implications over multiple years, in the absence of a systems-based approach. To evaluate the effect of three years of autumn cover crops on subsequent processing tomato (Solanum lycopersicum L.) production in 2010 and 2011, a field split-split-plot factorial design trial with effects of cover crop type, urea ammonium nitrate fertilizer rate (0 or 140 kg N ha-1 preplant broadcast incorporated) and tomato cultivar (early vs. late) was conducted. The main plot factor, cover crop, included a no cover crop control, oat (Avena sativa L.), winter cereal rye (hereafter referred to as rye) (Secale cereale L.), oilseed radish (OSR) (Raphanus sativus L. var. oleiferus Metzg Stokes), and mix of OSR and rye (OSR + rye) treatments. Cover crop biomass of 0.5 to 2.8 and 1.7 to 3.1 Mg ha-1 was attained in early Oct. and the following early May, respectively. In general, OSR increased soil mineral N during cover crop growth and into the succeeding summer tomato growing season, while the remaining cover crops did not differ from the no cover crop control. The lack of a cover crop by N rate interaction in soil and plant N analyses at harvest suggests that growers may not need to modify N fertilizer rates to tomatoes based on cover crop type. Processing tomato fruit quality at harvest (rots, insect or disease damage, Agtron colour, pH, or natural tomato soluble solids (NTSS)) was not affected by cover crop type. In both years, marketable yield in the no cover crop treatment was lower or not statistically different than all planted cover crops. Partial profit margins over both years were 1320 $ ha-1 higher with OSR and $960 higher with oat compared to the no cover crop control. Thus, results from a systems-based approach suggest that the cover crops tested had no observed negative impact on processing tomato production and have the potential to increase marketable yield and profit margins.

Winter cover crops on processing tomato yield, quality, pest pressure, nitrogen availability, and profit margins.

Directory of Open Access Journals (Sweden)

Kimberly D Belfry

Full Text Available Much of cover crop research to date focuses on key indicators of impact without considering the implications over multiple years, in the absence of a systems-based approach. To evaluate the effect of three years of autumn cover crops on subsequent processing tomato (Solanum lycopersicum L. production in 2010 and 2011, a field split-split-plot factorial design trial with effects of cover crop type, urea ammonium nitrate fertilizer rate (0 or 140 kg N ha-1 preplant broadcast incorporated and tomato cultivar (early vs. late was conducted. The main plot factor, cover crop, included a no cover crop control, oat (Avena sativa L., winter cereal rye (hereafter referred to as rye (Secale cereale L., oilseed radish (OSR (Raphanus sativus L. var. oleiferus Metzg Stokes, and mix of OSR and rye (OSR + rye treatments. Cover crop biomass of 0.5 to 2.8 and 1.7 to 3.1 Mg ha-1 was attained in early Oct. and the following early May, respectively. In general, OSR increased soil mineral N during cover crop growth and into the succeeding summer tomato growing season, while the remaining cover crops did not differ from the no cover crop control. The lack of a cover crop by N rate interaction in soil and plant N analyses at harvest suggests that growers may not need to modify N fertilizer rates to tomatoes based on cover crop type. Processing tomato fruit quality at harvest (rots, insect or disease damage, Agtron colour, pH, or natural tomato soluble solids (NTSS was not affected by cover crop type. In both years, marketable yield in the no cover crop treatment was lower or not statistically different than all planted cover crops. Partial profit margins over both years were 1320 $ ha-1 higher with OSR and $960 higher with oat compared to the no cover crop control. Thus, results from a systems-based approach suggest that the cover crops tested had no observed negative impact on processing tomato production and have the potential to increase marketable yield and profit

Landfill cover soil, soil solution, and vegetation responses to municipal landfill leachate applications.

Science.gov (United States)

Macdonald, Neil W; Rediske, Richard R; Scull, Brian T; Wierzbicki, David

2008-01-01

Municipal solid waste landfill leachate must be removed and treated to maintain landfill cover integrity and to prevent contamination of surface and ground waters. From 2003 to 2007, we studied an onsite disposal system in Ottawa County, Michigan, where leachate was spray irrigated on the vegetated landfill cover. We established six 20-m-diameter circular experimental plots on the landfill; three were spray irrigated as part of the operational system, and three remained as untreated control plots. We quantified the effects of leachate application on soil properties, soil solution chemistry, vegetative growth, and estimated solute leaching. The leachate had high mean levels of electrical conductivity (0.6-0.7 S m(-1)), Cl (760-900 mg L(-1)), and NH(4)-N (290-390 mg L(-1)) but was low in metals and volatile organic compounds. High rates of leachate application in 2003 (32 cm) increased soil electrical conductivity and NO(3)-N leaching, so a sequential rotation of spray areas was implemented to limit total leachate application to <9.6 cm yr(-1) per spray area. Concentrations of NO(3)-N and leaching losses remained higher on irrigated plots in subsequent years but were substantially reduced by spray area rotation. Leachate irrigation increased plant biomass but did not significantly affect soil metal concentrations, and plant metal concentrations remained within normal ranges. Rotating spray areas and timing irrigation to conform to seasonal capacities for evapotranspiration reduced the localized impacts of leachate application observed in 2003. Careful monitoring of undiluted leachate applications is required to avoid adverse impacts to vegetation or soils and elevated solute leaching losses.

Cover cropping impacts on arbuscular mycorrhizal fungi and soil aggregation

Science.gov (United States)

Cover crops are a management tool which can extend the period of time that a living plant is growing and conducting photosynthesis. This is critical for soil health, because most of the soil organisms, particularly the arbuscular mycorrhizal fungi, are limited by carbon. Research, on-farm, and demon...

Coping with the node problem in quantum hydrodynamics: The covering function method

International Nuclear Information System (INIS)

Babyuk, Dmytro; Wyatt, Robert E.

2004-01-01

A conceptually simple approach, the covering function method (CFM), is developed to cope with the node problem in the hydrodynamic formulation of quantum mechanics. As nodes begin to form in a scattering wave packet (detected by a monitor function), a nodeless covering wave function is added to it yielding a total function that is also nodeless. Both local and global choices for the covering function are described. The total and covering functions are then propagated separately in the hydrodynamic picture. At a later time, the actual wave function is recovered from the two propagated functions. The results obtained for Eckart barrier scattering in one dimension are in excellent agreement with exact results, even for very long propagation times t=1.2 ps. The capability of the CFM is also demonstrated for multidimensional propagation of a vibrationally excited wave packet

LAND COVER CHANGE MONITORING OF TYPICAL FUNCTIONAL COMMUNITIES OF SICHUAN PROVINCE BASED ON ZY-3 DATA

Directory of Open Access Journals (Sweden)

G. M. Li

2018-04-01

Full Text Available According to the function, land space types are divided into key development areas, restricted development areas and forbidden development areas in Sichuan Province. This paper monitors and analyses the changes of land cover in different typical functional areas from 2010 to 2017, which based on ZY-3 high-score images data and combined with statistical yearbook and thematic data of Sichuan Province. The results show that: The land cover types of typical key development zones are mainly composed of cultivated land, forest land, garden land, and housing construction land, which accounts for the total area of land cover 87 %. The land cover types of typical restricted development zone mainly consists of forest land and grassland, which occupy 97.71 % of the total area of the surface coverage. The land cover types of the typical prohibition development zone mainly consist of forest land, grassland, desert and bared earth, which accounts for the total area of land cover 99.31 %.

Land Cover Change Monitoring of Typical Functional Communities of Sichuan Province Based on ZY-3 Data

Science.gov (United States)

Li, G. M.; Li, S.; Ying, G. W.; Wu, X. P.

2018-04-01

According to the function, land space types are divided into key development areas, restricted development areas and forbidden development areas in Sichuan Province. This paper monitors and analyses the changes of land cover in different typical functional areas from 2010 to 2017, which based on ZY-3 high-score images data and combined with statistical yearbook and thematic data of Sichuan Province. The results show that: The land cover types of typical key development zones are mainly composed of cultivated land, forest land, garden land, and housing construction land, which accounts for the total area of land cover 87 %. The land cover types of typical restricted development zone mainly consists of forest land and grassland, which occupy 97.71 % of the total area of the surface coverage. The land cover types of the typical prohibition development zone mainly consist of forest land, grassland, desert and bared earth, which accounts for the total area of land cover 99.31 %.

Covering soils and vegetations during decommissioning disposal of a uranium mine

International Nuclear Information System (INIS)

Feng Weihua

2010-01-01

The disposals of waste ore dumps and tailings are an important part in the decommissioning disposal of uranium mines. Important indexes of the disposal include stabilization, harmlessness, rehabilitation and improvement of the ecological environment. These are closely related with vegetations. Taking example of decommissioning disposal of a uranium mine in Guizhou province, the selection of grasses and effects after covering soils and planting grasses are introduced. It is pointed out that covering soils and vegetations play an important role in decommissioning disposal of uranium mines. (authors)

Recent progress in the feasibility study for the first nuclear power plant in Indonesia

International Nuclear Information System (INIS)

Subki, I.R.; Iskandar, A.; Supadi, S.

1994-01-01

In September 1989 the Indonesian Government decided to perform a Nuclear Power Plant feasibility study, including a comprehensive investigation of Muris site. This presentation reports on the progress to date in the two main components of this study: (a) the non-site studies, covering energy economics, financing, technical and safety aspects, the fuel cycle and waste management as well as general management aspects, and (b) site and environmental studies, covering field investigations, assessment of site selection, site qualification/evaluation, environmental, socio-economic and cultural impacts. The study is carried out under a comprehensive quality assurance programme developed by a consultancy company - NEWJEC Inc., which compiles with IAEA recommendations and was approved by BATAN. A summary of the main results, recommendations and general conclusions is presented. It is estimated that the total investment for the construction of 2 x 900 MWe or 3 x 600 MWe class Nuclear Power Plant units would be around US$7 to US$9 billion. 8 tabs

Assessing the impact of climate variability on catchment water balance and vegetation cover

Directory of Open Access Journals (Sweden)

X. Xu

2012-01-01

Full Text Available Understanding the interactions among climate, vegetation cover and the water cycle lies at the heart of the study of watershed ecohydrology. Recently, considerable attention is being paid to the effect of climate variability on catchment water balance and also associated vegetation cover. In this paper, we investigate the general pattern of long-term water balance and vegetation cover (as reflected by fPAR among 193 study catchments in Australia through statistical analysis. We then employ the elasticity analysis approach for quantifying the effects of climate variability on hydrologic partitioning (including total, surface and subsurface runoff and on vegetation cover (including total, woody and non-woody vegetation cover. Based on the results of statistical analysis, we conclude that annual runoff (R, evapotranspiration (E and runoff coefficient (R/P increase with vegetation cover for catchments in which woody vegetation is dominant and annual precipitation is relatively high. Control of water available on annual evapotranspiration in non-woody dominated catchments is relatively stronger compared to woody dominated ones. The ratio of subsurface runoff to total runoff (R_g/R also increases with woody vegetation cover. Through the elasticity analysis of catchment runoff, it is shown that precipitation (P in current year is the most important factor affecting the change in annual total runoff (R, surface runoff (R_s and subsurface runoff (R_g. The significance of other controlling factors is in the order of annual precipitation in previous years (P₋₁ and P₋₂, which represents the net effect of soil moisture and annual mean temperature (T in current year. Change of P by +1% causes a +3.35% change of R, a +3.47% change of R_s and a +2.89% change of

Climatological determinants of woody cover in Africa.

Science.gov (United States)

Good, Stephen P; Caylor, Kelly K

2011-03-22

Determining the factors that influence the distribution of woody vegetation cover and resolving the sensitivity of woody vegetation cover to shifts in environmental forcing are critical steps necessary to predict continental-scale responses of dryland ecosystems to climate change. We use a 6-year satellite data record of fractional woody vegetation cover and an 11-year daily precipitation record to investigate the climatological controls on woody vegetation cover across the African continent. We find that-as opposed to a relationship with only mean annual rainfall-the upper limit of fractional woody vegetation cover is strongly influenced by both the quantity and intensity of rainfall events. Using a set of statistics derived from the seasonal distribution of rainfall, we show that areas with similar seasonal rainfall totals have higher fractional woody cover if the local rainfall climatology consists of frequent, less intense precipitation events. Based on these observations, we develop a generalized response surface between rainfall climatology and maximum woody vegetation cover across the African continent. The normalized local gradient of this response surface is used as an estimator of ecosystem vegetation sensitivity to climatological variation. A comparison between predicted climate sensitivity patterns and observed shifts in both rainfall and vegetation during 2009 reveals both the importance of rainfall climatology in governing how ecosystems respond to interannual fluctuations in climate and the utility of our framework as a means to forecast continental-scale patterns of vegetation shifts in response to future climate change.

Accumulation pattern of total nonstructural carbohydrate in ...

African Journals Online (AJOL)

The pattern of total nonstructural carbohydrate (TNC) accumulation in strawberry (Fragaria ananassa Duch.) nursery runner plants, cv. eCamarosaf, was determined for three growing seasons. Plant growth and fruit production patterns were also evaluated. The experiments were carried out on plants propagated in high ...

Intake of total, animal and plant proteins, and their food sources in 10 countries in the European Prospective Investigation into Cancer and Nutrition.

Science.gov (United States)

Halkjaer, J; Olsen, A; Bjerregaard, L J; Deharveng, G; Tjønneland, A; Welch, A A; Crowe, F L; Wirfält, E; Hellstrom, V; Niravong, M; Touvier, M; Linseisen, J; Steffen, A; Ocké, M C; Peeters, P H M; Chirlaque, M D; Larrañaga, N; Ferrari, P; Contiero, P; Frasca, G; Engeset, D; Lund, E; Misirli, G; Kosti, M; Riboli, E; Slimani, N; Bingham, S

2009-11-01

To describe dietary protein intakes and their food sources among 27 redefined centres in 10 countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC). Between 1995 and 2000, 36 034 persons, aged between 35 and 74 years, were administered a standardized 24-h dietary recall (24-HDR) using a computerized interview software programme (EPIC-SOFT). Intakes (g/day) of total, animal and plant proteins were estimated using the standardized EPIC Nutrient Database (ENDB). Mean intakes were adjusted for age, and weighted by season and day of recall. Mean total and animal protein intakes were highest in the Spanish centres among men, and in the Spanish and French centres among women; the lowest mean intakes were observed in the UK health-conscious group, in Greek men and women, and in women in Potsdam. Intake of plant protein was highest among the UK health-conscious group, followed by some of the Italian centres and Murcia, whereas Sweden and Potsdam had the lowest intake. Cereals contributed to the highest proportion of plant protein in all centres. The combined intake of legumes, vegetables and fruit contributed to a greater proportion of plant protein in the southern than in the northern centres. Total meat intake (with some heterogeneity across subtypes of meat) was, with few exceptions, the most important contributor to animal protein in all centres, followed by dairy and fish products. This study shows that intake of protein, especially of animal origin, differs across the 10 European countries, and also shows some differences in food sources of protein across Europe.

Influence of cover crops on insect pests and predators in conservation tillage cotton.

Science.gov (United States)

Tillman, Glynn; Schomberg, Harry; Phatak, Sharad; Mullinix, Benjamin; Lachnicht, Sharon; Timper, Patricia; Olson, Dawn

2004-08-01

In fall 2000, an on-farm sustainable agricultural research project was established for cotton, Gossypium hirsutum L., in Tift County, Georgia. The objective of our 2-yr research project was to determine the impact of several cover crops on pest and predator insects in cotton. The five cover crop treatments included 1) cereal rye, Secale cereale L., a standard grass cover crop; 2) crimson clover, Trifolium incarnatum L., a standard legume cover crop; 3) a legume mixture of balansa clover, Trifolium michelianum Savi; crimson clover; and hairy vetch, Vicia villosa Roth; 4) a legume mixture + rye combination; and 5) no cover crop in conventionally tilled fields. Three main groups or species of pests were collected in cover crops and cotton: 1) the heliothines Heliothis virescens (F.) and Helicoverpa zea (Boddie); 2) the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois); and 3) stink bugs. The main stink bugs collected were the southern green stink bug, Nezara viridula (L.); the brown stink bug, Euschistus servus (Say); and the green stink bug, Acrosternum hilare (Say). Cotton aphids, Aphis gossypii Glover, were collected only on cotton. For both years of the study, the heliothines were the only pests that exceeded their economic threshold in cotton, and the number of times this threshold was exceeded in cotton was higher in control cotton than in crimson clover and rye cotton. Heliothine predators and aphidophagous lady beetles occurred in cover crops and cotton during both years of the experiment. Geocoris punctipes (Say), Orius insidiosus (Say), and red imported fire ant, Solenopsis invicta Buren were relatively the most abundant heliothine predators observed. Lady beetles included the convergent lady beetle, Hippodamia convergens Guérin-Méneville; the sevenspotted lady beetle, Coccinella septempunctata L.; spotted lady beetle, Coleomegilla maculata (DeGeer); and the multicolored Asian lady beetle, Harmonia axyridis (Pallas). Density of G. punctipes was

Diel hysteresis between soil respiration and soil temperature in a biological soil crust covered desert ecosystem.

Science.gov (United States)

Guan, Chao; Li, Xinrong; Zhang, Peng; Chen, Yongle

2018-01-01

Soil respiration induced by biological soil crusts (BSCs) is an important process in the carbon (C) cycle in arid and semi-arid ecosystems, where vascular plants are restricted by the harsh environment, particularly the limited soil moisture. However, the interaction between temperature and soil respiration remains uncertain because of the number of factors that control soil respiration, including temperature and soil moisture, especially in BSC-dominated areas. In this study, the soil respiration in moss-dominated crusts and lichen-dominated crusts was continuously measured using an automated soil respiration system over a one-year period from November 2015 to October 2016 in the Shapotou region of the Tengger Desert, northern China. The results indicated that over daily cycles, the half-hourly soil respiration rates in both types of BSC-covered areas were commonly related to the soil temperature. The observed diel hysteresis between the half-hourly soil respiration rates and soil temperature in the BSC-covered areas was limited by nonlinearity loops with semielliptical shapes, and soil temperature often peaked later than the half-hourly soil respiration rates in the BSC-covered areas. The average lag times between the half-hourly soil respiration rates and soil temperature for both types of BSC-covered areas were two hours over the diel cycles, and they were negatively and linearly related to the volumetric soil water content. Our results highlight the diel hysteresis phenomenon that occurs between soil respiration rates and soil temperatures in BSC-covered areas and the negative response of this phenomenon to soil moisture, which may influence total C budget evaluations. Therefore, the interactive effects of soil temperature and moisture on soil respiration in BSC-covered areas should be considered in global carbon cycle models of desert ecosystems.

Aspects related to the decommissioning of the nuclear power plants

International Nuclear Information System (INIS)

Goicea, Andrei; Andrei, Veronica

2003-01-01

All power plants, either coal, gas or nuclear, at the end of their life needs to be decommissioned and demolished and thus, to made the site available for other uses. The first generation nuclear power plants were designed for a life of about 30 years and some of them proved capable of continuing well beyond this term. Newer plants have been designed for a 40 to 60 years operating life. To date, other 90 commercial power reactors have been retired from operation. For nuclear power plants and nuclear facilities in general the decommissioning process consists of some or all of the following activities: the safe management of nuclear materials held in the facility, cleaning-up of radioactivity (decontamination), plant dismantling, progressive demolition of the plant and site remediation. Following the decommissioning, the regulatory controls covering facility end, partially or totally, and the safe site is released for appropriate alternative use. Cernavoda NPP is a young plant and it can benefit from the continuously developing experience of the decommissioning process at the international level. The current experience allows the most metallic parts of a nuclear power to be decontaminated and recycled and makes available proven techniques and equipment to dismantle nuclear facilities safely. As experience is gained, decommissioning costs for nuclear power plants, including disposal of associated wastes, are reducing and thus, contribute in a smaller fraction to the total cost of electricity generation. The new specific Romanian regulations establish a funding system for decommissioning and provisions for long-term radioactive waste management. In the near future a decommissioning plan will be made available for Cernavoda NPP. Since the plant has only 7 years operation, that plan can be improved in order to benefit from international experience that is growing. (authors)

Reduced cover of drifting macroalgae following nutrient reduction in Danish coastald waters

DEFF Research Database (Denmark)

Rasmussen, Jonas Ribergaard; Dromph, Karsten Mikael; Göke, Cordula

2015-01-01

conditions and environmental characteristics. The cover of drifting algae was positively related to total nitrogen concentration and Secchi depth but negatively related to exposure, salinity and mean summer temperature. The cover of drifting macroalgae showed significant declines over the past two decades...

Distribution and variability of total mercury in snow cover?a case study from a semi-urban site in Pozna?, Poland

OpenAIRE

Siudek, Patrycja

2016-01-01

In the present paper, the inter-seasonal Hg variability in snow cover was examined based on multivariate statistical analysis of chemical and meteorological data. Samples of freshly fallen snow cover were collected at the semi-urban site in Pozna? (central Poland), during 3-month field measurements in winter 2013. It was showed that concentrations of atmospherically deposited Hg were highly variable in snow cover, from 0.43 to 12.5?ng?L?1, with a mean value of 4.62?ng?L?1. The highest Hg conc...

Development of deforestation and land cover database for Bhutan (1930-2014).

Science.gov (United States)

Reddy, C Sudhakar; Satish, K V; Jha, C S; Diwakar, P G; Murthy, Y V N Krishna; Dadhwal, V K

2016-12-01

Bhutan is a mountainous country located in the Himalayan biodiversity hotspot. This study has quantified the total area under land cover types, estimated the rate of forest cover change, analyzed the changes across forest types, and modeled forest cover change hotpots in Bhutan. The topographical maps and satellite remote sensing images were analyzed to get the spatial patterns of forest and associated land cover changes over the past eight decades (1930-1977-1987-1995-2005-2014). Forest is the largest land cover in Bhutan and constitutes 68.3% of the total geographical area in 2014. Subtropical broad leaved hill forest is predominant type occupies 34.1% of forest area in Bhutan, followed by montane dry temperate (20.9%), montane wet temperate (18.9%), Himalayan moist temperate (10%), and tropical moist sal (8.1%) in 2014. The major forest cover loss is observed in subtropical broad leaved hill forest (64.5 km 2 ) and moist sal forest (9.9 km 2 ) from 1977 to 2014. The deforested areas have mainly been converted into agriculture and contributed for 60.9% of forest loss from 1930 to 2014. In spite of major decline of forest cover in time interval of 1930-1977, there is no net rate of deforestation is recorded in Bhutan since 1995. Forest cover change analysis has been carried out to evaluate the conservation effectiveness in "Protected Areas" of Bhutan. Hotspots that have undergone high transformation in forest cover for afforestation and deforestation were highlighted in the study for conservation prioritisation. Forest conservation policies in Bhutan are highly effective in controlling deforestation as compared to neighboring Asian countries and such service would help in mitigating climate change.

Timing of glyphosate applications to wheat cover crops to reduce onion stunting caused by Rhizoctonia solani

Science.gov (United States)

Stunting caused by Rhizoctonia spp. is economically important in irrigated onion bulb crops in the semi-arid Columbia Basin of Oregon and Washington, where cereal winter cover crops commonly are planted the previous fall to prevent wind erosion of soil. The cover crop is killed with herbicide applic...

Total Quality Management Seminar.

Science.gov (United States)

Massachusetts Career Development Inst., Springfield.

This booklet is one of six texts from a workplace literacy curriculum designed to assist learners in facing the increased demands of the workplace. The booklet contains seven sections that cover the following topics: (1) meaning of total quality management (TQM); (2) the customer; (3) the organization's culture; (4) comparison of management…

New nuclear power plants in Europe 1984. Pt 2

International Nuclear Information System (INIS)

Anon.

1984-01-01

The atw report on new nuclear power plants in Europe contains both a survey of the Federal Republic of Germany, which was pubslished in the April 1984 issue, and an overview of the nuclear power plant situation in 26 European countries including the Soviet Union and six other CMEA countries. Also this year's review includes specific status reports, complete with technical information, about all nuclear generating units under construction, in the project and concrete planning phases. The fifteen nuclear power plants newly commissioned in Europe since last year's atw report was published are covered in a similar way. Moreover, introductory summaries describe the plants in operation in each country and their 1983 electricity generation. A general introduction provides an outlook on developments in Western and Eastern Europe. The total number of nuclear power plants now in operation and under construction in Europe is 300 units with an aggregate gross 219, 320 MWe. Of these, 185 units are located in Western Europe, 115 in Eastern Europe. The units currently in operation of this total are 180 with 103,978 MWe in sixteen European countries; of these, 126 units with 74,869 MWe are run in eleven West European countries, 54 units with an aggregate 29,109 MWe in five East European countries. Of the 120 nuclear generating units at present under construction with an aggregate 115,342 MWe in fifteen European countries, 59 units with 63,442 MWe are located in eight West European, 61 units with 51,900 MWe in seven East European countries. (orig./UA) [de

Nitrogen Transfer from Cover Crop Residues to Onion Grown under Minimum Tillage in Southern Brazil

Directory of Open Access Journals (Sweden)

Leoncio de Paula Koucher

2017-08-01

Full Text Available ABSTRACT Nitrogen derived from cover crop residues may contribute to the nutrition of onion grown under minimum tillage (MT and cultivated in rotation. The aim of this study was to evaluate the N transferred from different cover crop residues to the onion crop cultivated under MT in southern Brazil. In June 2014, oilseed radish, black oat, and oilseed radish + black oat residues labeled with 15N were deposited on the soil surface before transplanting onions. During the growth season and at harvest, young expanded onion leaves, complete plants, and samples from different soil layers were collected and analyzed for recovery of 15N-labeled residue. Oilseed radish decomposed faster than other residues and 4 % of residue N was recovered in leaves and bulbs at harvest, but in general, N in plant organs was derived from sources other than the cover crop residues. In addition, leaf N was in the proper range for all treatments and was adequately mobilized to the bases for bulbing. The N derived from decomposing residues contributed little to onion development and the use of these plants should be chosen based on their advantages for physical and biological soil quality.

Plants used by Megachile (Moureapis sp. (Hymenoptera: Megachilidae in the provisioning of their nests

Directory of Open Access Journals (Sweden)

MLT. Buschini

Full Text Available This study was carried out in the Parque Municipal das Araucárias, located in the municipality of Guarapuava (PR from May (06 to April (07. Its aim was to investigate which plants are used by Megachile (Moureapis sp in provisioning of larvae, and to verify if this bee is oligolectic or polilectic. The collection of the plants was carried out during the bees activity period and in an area covering a 500 m radius from where the nests had been built. A sample of pollens from founded nests and from flowers was used to make permanent slides using the acetolysis method and with the aid of a light microscope, all pollen grains were examined in order to identify the plants used by this bee. A total of 80 pollen grain slides, from 16 nests were analysed. Although 99 plants were collected close to the bee's nesting site, in nest slides, the pollen of Ludwigia peruviana (36% and Ludwigia sericea (63.6% (Onagraceae accounted for 99.6% of the total amount of pollen collected. With these results we are able to conclude that Megachile (Moureapis sp is an oligolectic species and that these plants species are their important pollen source.

Evaluation of the performance of the Tyson Foods wastewater treatment plant for nitrogen removal.

Science.gov (United States)

Ubay-Cokgor, E; Randall, C W; Orhon, D

2005-01-01

In this paper, the performance of the Tyson Foods wastewater treatment plant with an average flow rate of 6500 m3/d was evaluated before and after upgrading of the treatment system for nitrogen removal. This study was also covered with an additional recommendation of BIOWIN BNR program simulation after the modification period to achieve an additional nutrient removal. The results clearly show that the upgrading was very successful for improved nitrogen removal, with a 57% decrease on the total nitrogen discharge. There also were slight reductions in the discharged loads of biological oxygen demand, total suspended solids, ammonium and total phosphorus with denitrification, even though the effluent flow was higher during operation of the nitrogen removal configuration.

Canopy cover negatively affects arboreal ant species richness in a tropical open habitat

Directory of Open Access Journals (Sweden)

A. C. M. Queiroz

Full Text Available Abstract We tested the hypothesis of a negative relationship between vegetation characteristics and ant species richness in a Brazilian open vegetation habitat, called candeial. We set up arboreal pitfalls to sample arboreal ants and measured the following environmental variables, which were used as surrogate of environmental heterogeneity: tree richness, tree density, tree height, circumference at the base of the plants, and canopy cover. Only canopy cover had a negative effect on the arboreal ant species richness. Vegetation characteristics and plant species composition are probably homogeneous in candeial, which explains the lack of relationship between other environmental variables and ant richness. Open vegetation habitats harbor a large number of opportunistic and generalist species, besides specialist ants from habitats with high temperatures. An increase in canopy cover decreases sunlight incidence and may cause local microclimatic differences, which negatively affect the species richness of specialist ants from open areas. Canopy cover regulates the richness of arboreal ants in open areas, since only few ant species are able to colonize sites with dense vegetation; most species are present in sites with high temperature and luminosity. Within open vegetation habitats the relationship between vegetation characteristics and species richness seems to be the opposite from closed vegetation areas, like forests.

Exogenous application of plant growth regulators increased the total ...

African Journals Online (AJOL)

PRECIOUS

2009-11-02

Nov 2, 2009 ... the exogenous application of flavonoids reports plant growth regulation ... method used for extraction and quantification of endogenous gibberellins was ... 365 nm) while separation was done on a C18 reverse-phase HPLC.

Plant establishment and soil microenvironments in Utah juniper masticated woodlands

Science.gov (United States)

Kert R. Young

2012-01-01

Juniper (Juniperus spp.) encroachment into sagebrush (Artemisia spp.) and bunchgrass communities has reduced understory plant cover and allowed juniper trees to dominate millions of hectares of semiarid rangelands. Trees are mechanically masticated or shredded to decrease wildfire potential and increase desirable understory plant cover. When trees are masticated after...

The suitability of non-legume cover crops for inorganic soil nitrogen immobilisation in the transition period to an organic no-till system

Directory of Open Access Journals (Sweden)

Lars Rühlemann

2016-01-01

Full Text Available The aim of the study was to evaluate non-legume cover crops for growing no-till grain legumes in organic farming systems. Evaluated cover crops should be able to suppress weed growth, reduce plant available nitrogen in the soil and produce large amounts of biomass with slow N mineralisation. Six non-legume species; spring rye (Secale cereale L., black oat (Avena sativa L., sunflower (Helianthus annuus L., white mustard (Sinapis alba L., buckwheat (Fagopyrum esculentum Moench and hemp (Cannabis sativa L. were tested. Plots with organic fertiliser (50 kg N ha−1 and without fertiliser incorporation at three locations in south-east Germany were trialled and the cover crops’ ability to produce biomass and accumulate N in plant compartments was evaluated. The N mineralisation from stem and leaf material was simulated using the STICS model. The biomass production ranged from 0.95 to 7.73 Mg ha−1, with fertiliser increasing the total biomass at locations with low-N status. Sunflower consistently displayed large biomass and N accumulation at all locations and fertiliser variations, although not always significantly more than other species. Most N was stored in sunflower leaf material, which can be easily mineralised making it less suited as cover crop before no-till sown spring grain legumes. Rye, which produced slightly less biomass, but accumulated more N in the stem biomass, would be better suited than sunflower in this type of system. The N mineralisation simulation from rye biomass indicated long N immobilisation periods potentially improving weed suppression within no-till sown legume cash crops.

Plants. Ag Ed Environmental Education Series.

Science.gov (United States)

Tulloch, Rodney W.

Designed to serve as a resource tool in a high school vocational agriculture curriculum dealing with the environment as it relates to agriculture, this unit is concerned with plants. Plants are defined and their characteristics described. A section on the effects of environment on higher plants covers temperature, light, water, nutrients, air,…

Calculation set for design and optimization of vegetative soil covers Sandia National Laboratories, Albuquerque, New Mexico.

Energy Technology Data Exchange (ETDEWEB)

Peace, Gerald L.; Goering, Timothy James (GRAM, Inc., Albuquerque, NM)

2005-02-01

This study demonstrates that containment of municipal and hazardous waste in arid and semiarid environments can be accomplished effectively without traditional, synthetic materials and complex, multi-layer systems. This research demonstrates that closure covers combining layers of natural soil, native plant species, and climatic conditions to form a sustainable, functioning ecosystem will meet the technical equivalency criteria prescribed by the U. S. Environmental Protection Agency. In this study, percolation through a natural analogue and an engineered cover is simulated using the one-dimensional, numerical code UNSAT-H. UNSAT-H is a Richards. equation-based model that simulates soil water infiltration, unsaturated flow, redistribution, evaporation, plant transpiration, and deep percolation. This study incorporates conservative, site-specific soil hydraulic and vegetation parameters. Historical meteorological data are used to simulate percolation through the natural analogue and an engineered cover, with and without vegetation. This study indicates that a 3-foot (ft) cover in arid and semiarid environments is the minimum design thickness necessary to meet the U. S. Environmental Protection Agency-prescribed technical equivalency criteria of 31.5 millimeters/year and 1 x 10{sup -7} centimeters/second for net annual percolation and average flux, respectively. Increasing cover thickness to 4 or 5 ft results in limited additional improvement in cover performance.

Estimated radiological effects of the normal discharge of radioactivity from nuclear power plants in the Netherlands with a total capacity of 3500 MWe

International Nuclear Information System (INIS)

Lugt, G. van der; Wijker, H.; Kema, N.V.

1977-01-01

In the Netherlands discussions are going on about the installation of three nuclear power plants, leading with the two existing plants to a total capacity of 3500 MWe. To have an impression of the radiological impact of this program, calculations were carried out concerning the population doses due to the discharge of radioactivity from the plants during normal operation. The discharge via the ventilation stack gives doses due to noble gases, halogens and particulate material. The population dose due to the halogens in the grass-milk-man chain is estimated using the real distribution of grass-land around the reactor sites. It could be concluded that the population dose due to the contamination of crops and fruit is negligeable. A conservative estimation is made for the dose due to the discharge of tritium. The population dose due to the discharge in the cooling water is calculated using the following pathways: drinking water; consumption of fish; consumption of meat from animals fed with fish products. The individual doses caused by the normal discharge of a 1000 MWe plant appeared to be very low, mostly below 1 mrem/year. The population dose is in the order of some tens manrems. The total dose of the 5 nuclear power plants to the dutch population is not more than 70 manrem. Using a linear dose-effect relationship the health effects to the population are estimated and compared with the normal frequency

Short-term contributions of cover crop surface residue return to soil carbon and nitrogen contents in temperate Australia.

Science.gov (United States)

Zhou, Xiaoqi; Wu, Hanwen; Li, Guangdi; Chen, Chengrong

2016-11-01

Cover crop species are usually grown to control weeds. After cover crop harvest, crop residue is applied on the ground to improve soil fertility and crop productivity. Little information is available about quantifying the contributions of cover crop application to soil total carbon (C) and nitrogen (N) contents in temperate Australia. Here, we selected eight cover crop treatments, including two legume crops (vetch and field pea), four non-legume crops (rye, wheat, Saia oat, and Indian mustard), a mixture of rye and vetch, and a nil-crop control in temperate Australia to calculate the contributions of cover crops (crop growth + residue decomposition) to soil C and N contents. Cover crops were sown in May 2009 (autumn). After harvest, the crop residue was placed on the soil surface in October 2009. Soil and crop samples were collected in October 2009 after harvest and in May 2010 after 8 months of residue decomposition. We examined cover crop residue biomass, soil and crop total C and N contents, and soil microbial biomass C and N contents. The results showed that cover crop application increased the mean soil total C by 187-253 kg ha -1 and the mean soil total N by 16.3-19.1 kg ha -1 relative to the nil-crop treatment, except for the mixture treatment, which had similar total C and N contents to the nil-crop control. Cover crop application increased the mean soil microbial biomass C by 15.5-20.9 kg ha -1 and the mean soil microbial biomass N by 4.5-10.2 kg ha -1 . We calculated the apparent percentage of soil total C derived from cover crop residue C losses and found that legume crops accounted for 10.6-13.9 %, whereas non-legume crops accounted for 16.4-18.4 % except for the mixture treatment (0.2 %). Overall, short-term cover crop application increased soil total C and N contents and microbial biomass C and N contents, which might help reduce N fertilizer use and improve sustainable agricultural development.

Effects of Cover Crops to Offset Soil Carbon Changes Under No-till on an Ohio farm when Biomass is Harvested

Science.gov (United States)

Kimble, J. M.; Everett, L. R.; Richards, W.

2003-12-01

The results of a long term experiment to look at the use of cover crops and there effect on soil organic carbon. No-till has been shown to increase SOC and improve the overall soil quality under conditions where the biomass has been returned to the field. However, biomass may be removed as silage or for use in biofuels. The removal will reduce the inputs to the field so to overcome the amount of biomass not returned to the soil different cover crops were used. This experiment was done on a working farm where the corn biomass was being removed as silage. Four cover crops were planted in early September of 2002: rye, oats, clover, and canola with two controls, one with no cover crop and one where corn stubble was left on the field. The soils were sampled soon after the crops were planted and again in the spring of 2003 before the cover crops were killed just prior to planting. The first results indicate that the most root biomass was produced by the rye followed by oats then canola and then clover.

Feasibility studies to improve plant availability and reduce total installed cost in IGCC plants

Energy Technology Data Exchange (ETDEWEB)

Sullivan, Kevin [General Electric Company, Houston, TX (United States); Anasti, William [General Electric Company, Houston, TX (United States); Fang, Yichuan [General Electric Company, Houston, TX (United States); Subramanyan, Karthik [General Electric Company, Houston, TX (United States); Leininger, Tom [General Electric Company, Houston, TX (United States); Zemsky, Christine [General Electric Company, Houston, TX (United States)

2015-03-30

The main purpose of this project is to look at technologies and philosophies that would help reduce the costs of an Integrated Gasification Combined Cycle (IGCC) plant, increase its availability or do both. GE’s approach to this problem is to consider options in three different areas: 1) technology evaluations and development; 2) constructability approaches; and 3) design and operation methodologies. Five separate tasks were identified that fall under the three areas: Task 2 – Integrated Operations Philosophy; Task 3 – Slip Forming of IGCC Components; Task 4 – Modularization of IGCC Components; Task 5 – Fouling Removal; and Task 6 – Improved Slag Handling. Overall, this project produced results on many fronts. Some of the ideas could be utilized immediately by those seeking to build an IGCC plant in the near future. These include the considerations from the Integrated Operations Philosophy task and the different construction techniques of Slip Forming and Modularization (especially if the proposed site is in a remote location or has a lack of a skilled workforce). Other results include ideas for promising technologies that require further development and testing to realize their full potential and be available for commercial operation. In both areas GE considers this project to be a success in identifying areas outside the core IGCC plant systems that are ripe for cost reduction and ity improvement opportunities.

Microbial biomass and nutrient dynamics during decomposition of cover crop mixtures

NARCIS (Netherlands)

Drost, S.M.

2016-01-01

Sustainable agriculture is needed to reduce losses of soil organic matter (SOM) and to ensure crop production with a minimum of negative impact on the environment. Cover crops, planted in the fallow season, are commonly used to improve soil functions, such as soil structure, nutrient cycling,

Disponibilidade hídrica, radiação solar e fotossíntese em videiras 'Cabernet Sauvignon' sob cultivo protegido Water supply, solar radiation and photosynthesis in 'Cabernet Sauvignon' grapevines under plastic covering

Directory of Open Access Journals (Sweden)

Clenilso Sehnen Mota

2009-06-01

Full Text Available O objetivo deste trabalho foi avaliar os efeitos da cobertura de videira 'Cabernet Sauvignon' com lona plástica translúcida sobre a disponibilidade de luz e água, a concentração foliar de clorofila e a fotossíntese. As plantas com cinco anos de idade foram conduzidas em sistema 'Y' sobre porta-enxerto Paulsen 1103. O experimento seguiu o delineamento em blocos ao acaso, com dois tratamentos (plantas sem e com cobertura plástica e quatro repetições de 15 plantas (unidade experimental. A cobertura plástica reduziu o suprimento às plantas de radiações ultravioleta (UV, azul, verde, vermelho, vermelho distante e total (300-750 nm, bem como a disponibilidade hídrica nas camadas superficiais do solo (0-30 cm. As plantas cobertas apresentaram maior taxa fotossintética máxima e condutância estomática em relação às plantas descobertas. Os pontos de compensação e de saturação de luz, a eficiência quântica aparente, a respiração no escuro, a concentração foliar de clorofilas e o potencial hídrico foliar de base não foram influenciados pelo uso da cobertura plástica. A cobertura plástica reduziu a radiação e a disponibilidade hídrica nas camadas superficiais do solo, porém favoreceu a assimilação foliar de CO2.The objective of this work was to assess the effects of translucent plastic overhead cover on light and water supply of vineyard and leaf chlorophyll content and photosynthesis in grapevines. Five-year-old 'Cabernet Sauvignon' grapevines (Vitis vinifera L. grafted on Paulsen 1103 rootstock and raised as 'Y' management system were used. The experiment followed a randomized block design, with two treatments (uncovered and covered plants and four replicates of 15 plants (experimental unit. The plastic cover reduced the supply of ultraviolet (UV, blue, green, red, far red, and total (300-750 nm radiation to the plants, as well as the water availability at the superficial soil layers (0-30 cm. Covered plants had

Integrated Nuclear Recycle Plant

International Nuclear Information System (INIS)

Patodi, Anuj; Parashar, Abhishek; Samadhiya, Akshay K.; Ray, Saheli; Dey, Mitun; Singh, K.K.

2017-01-01

Nuclear Recycle Board (NRB), Tarapur proposes to set up an 'Integrated Nuclear Recycle Plant' at Tarapur. This will be located in the premises of BARC facilities. The project location is at coastal town of Tarapur, 130 Km north of Mumbai. Project area cover of INRP is around 80 hectares. The plant will be designed to process spent fuel received from Pressurized Heavy Water Reactors (PHWRs). This is the first large scale integrated plant of the country. INRP will process spent fuel obtained from indigenous nuclear power plants and perform left over nuclear waste disposal

Nitrate leaching from winter cereal cover crops using undisturbed soil-column lysimeters

Science.gov (United States)

Cover crops are important management practices for reducing nitrogen (N) leaching in the Chesapeake Bay watershed, which is under Total Maximum Daily Load restraints. Cool-season annual grasses such as barley, rye, or wheat are common cover crops, but studies are needed to directly compare field ni...

Root characteristics of cover crops and their erosion-reducing potential during concentrated runoff

Science.gov (United States)

de Baets, S.; Poesen, J.

2009-04-01

In the loam region in central Belgium, a lot of research has been conducted on the effects of cover crops for preventing splash and interrill erosion and on their nutrient pumping effectiveness. As this is a very effective erosion and environment conservation technique, planting cover crops during the winter season is widely applied in the loess belt. Most of these cover crops freeze at the beginning of the winter period. Consequently, the above-ground biomass becomes less effective in protecting the soil from water erosion. Apart from the effects of the above-ground biomass in protecting the soil against raindrop impacts and reducing flow velocities by the retarding effects of their stems, plant roots also play an important role in improving soil strength. Previous research showed that roots contribute to a large extent to the resistance of topsoils against concentrated flow erosion. Unfortunately, information on root properties of common cover crops (e.g. Sinapis alba, Phacelia tanacetifoli, Lolium perenne, Avena sativa, Secale cereale, Raphanus sativus subsp. oleiferus) is very scarce. Therefore, root density distribution with depth and their erosion-reducing effects during concentrated flow erosion were assessed by conducting root auger measurements and concentrated flow experiments at the end of the growth period (December). The preliminary results indicate that the studied cover crops are not equally effective in preventing soil loss by concentrated flow erosion at the end of the growing season. Cover crops with thick roots, such as Sinapis alba and Raphanus sativus subsp. oleiferus are less effective than cover crops with fine-branched roots such as Phacelia tanacetifoli, Lolium perenne (Ryegrass), Avena sativa (Oats) and Secale cereale (Rye) in preventing soil losses by concentrated flow erosion. These results enable soil managers to select the most suitable crops and maximize soil protection.

Land Cover - Minnesota Land Cover Classification System

Data.gov (United States)

Minnesota Department of Natural Resources — Land cover data set based on the Minnesota Land Cover Classification System (MLCCS) coding scheme. This data was produced using a combination of aerial photograph...

Total-system expertise in economically efficient operation of nuclear power plants

International Nuclear Information System (INIS)

2000-01-01

Siemens Nuclear Power GmbH can look back on well over 40 years of experience in developing and constructing nuclear power plants. 23 Power plant units of Siemens design are in operation in five countries, and in autumn this year, another one will start commercial operation, while yet another one is under construction. In comparative international power plant surveys, the Siemens-design systems usually rank in top positions when it comes to comparing systems availability and electric power generation, and Siemens have build a reputation in manufacturing power plants up to the highest safety standards worldwide. Our experience as a manufacturer of turnkey PWR and BWR type reactors, as well as our profound knowledge of international nuclear standardisation, engineering codes and safety guides, has been used and processed to the benefit of the services offered by Siemens, resulting in well-devised service packages, and enhancements and optimisation of our machinery and equipment. Siemens has of course obtained the relevant licenses and certification for all its services and products according to DIN ISO 9001, KTA and ASME standards [de

Soil resilience and yield performance in a vineyard established after intense pre-planting earthworks

Science.gov (United States)

Costantini, Edoardo; Valboa, Giuseppe; Gagnarli, Elena; Mocali, Stefano; Fabiani, Arturo; Priori, Simone; Simoni, Sauro; Storchi, Paolo; Perria, Rita; Vignozzi, Nadia; Agnelli, Alessandro

2017-04-01

Conventional earthworks undertaken before vine plantation may severely compromise soil functions and vine production, as a consequence of a decline of soil fertility caused by loss of organic matter and biological activity, along with changes in chemical and physical features of the topsoil due to the upset of the soil profile. This research was aimed at assessing the effects of conventional pre-planting earthworks on soil fertility and vine yield performance under organic farming. To this purpose, grape yield and quality along with soil chemical, physical and biological properties, were monitored over seven years in a young vineyard established in 2010 after soil leveling and deep ploughing, and in parallel in an older vineyard planted in 2000 after similar earthworks under the same soil and environment conditions. The vineyards (Vitis vinifera L., cv. Sangiovese) were located in the Chianti Classico district (Tuscany, Italy) on a stony calcareous soil classified as Cambic Skeletic Calcisol (loamic, aric) (WRB, 2014). Fertilization was based on annual applications of compost and shredded plant residues. According to the ordinary farming system, the older vineyard was kept free from grass covering during the first four years of growth by periodic tillage, in order to prevent nutritional competition, while in the following years it was managed by natural grass covering on alternate inter-rows. In the younger vineyard, grass covering needed to be postponed because of a delay in the vine development and grape yield induced by poor soil fertility. The results showed significant differences between the two vineyard, with the younger exhibiting lower total organic carbon (0.4 - 0.6 % vs 0.6 - 1.1 %), lower total nitrogen (0.07 - 0.11 % vs 0.10 - 0.15 %) and higher carbonate contents (32 - 38 % vs 21 -30 % total CaCO3), with no clear trend of recovery over time. Pre-planting earthworks also affected the structure and diversity of microbial and microarthropod communities

Effects of cover crops incorporation and nitrogen fertilization on N2O and CO2 emissions

Science.gov (United States)

Kandel, T. P.; Gowda, P. H.; Northup, B. K.; DuPont, J.; Somenahally, A. C.; Rocateli, A.

2017-12-01

In this study, we measured N2O and CO2 fluxes from plots planted to hairy vetch (winter cover crop) and broadleaf vetch (spring cover crop) as N sources for the following crabgrass (summer forage crop) in El Reno, Oklahoma, USA. Comparisons also included 0 and 60 kg ha-1 mineral N fertilizer supplied as dry urea. No significant N2O fluxes were observed during rapid growing periods of cover crops (March-April, 2017), however, large fluxes were observed after hairy vetch incorporation. Immediately after the hairy vetch biomass incorporation, large rainfall events were recorded. The fluxes subsided gradually with drying soil condition but were enhanced after every consecutive rainfall events. A rainfall induced flux measuring up to 8.2 kg N2O ha-1 day-1 was observed after 26 days of biomass incorporation. In total, 29 kg N2O ha-1 (18 kg N ha-1) was emitted within a month after biomass incorporation from hairy vetch plots. Growth of broadleaf vetch was poor and N2O fluxes were also lower. Similarly, plots fertilized with 60 kg N ha-1 had significant fluxes of N2O but the magnitude was much lower than the hairy vetch plots. Dynamics of N2O and CO fluxes correlated strongly. The results thus indicated that although cover crops may provide many environmental/agronomic benefits such as N fixation, soil carbon built-up, weed suppression and erosion control, high N2O emissions may dwarf these benefits.

Cacao Cultivation under Diverse Shade Tree Cover Allows High Carbon Storage and Sequestration without Yield Losses.

Science.gov (United States)

Abou Rajab, Yasmin; Leuschner, Christoph; Barus, Henry; Tjoa, Aiyen; Hertel, Dietrich

2016-01-01

One of the main drivers of tropical forest loss is their conversion to oil palm, soy or cacao plantations with low biodiversity and greatly reduced carbon storage. Southeast Asian cacao plantations are often established under shade tree cover, but are later converted to non-shaded monocultures to avoid resource competition. We compared three co-occurring cacao cultivation systems (3 replicate stands each) with different shade intensity (non-shaded monoculture, cacao with the legume Gliricidia sepium shade trees, and cacao with several shade tree species) in Sulawesi (Indonesia) with respect to above- and belowground biomass and productivity, and cacao bean yield. Total biomass C stocks (above- and belowground) increased fivefold from the monoculture to the multi-shade tree system (from 11 to 57 Mg ha-1), total net primary production rose twofold (from 9 to 18 Mg C ha-1 yr-1). This increase was associated with a 6fold increase in aboveground biomass, but only a 3.5fold increase in root biomass, indicating a clear shift in C allocation to aboveground tree organs with increasing shade for both cacao and shade trees. Despite a canopy cover increase from 50 to 93%, cacao bean yield remained invariant across the systems (variation: 1.1-1.2 Mg C ha-1 yr-1). The monocultures had a twice as rapid leaf turnover suggesting that shading reduces the exposure of cacao to atmospheric drought, probably resulting in greater leaf longevity. Thus, contrary to general belief, cacao bean yield does not necessarily decrease under shading which seems to reduce physical stress. If planned properly, cacao plantations under a shade tree cover allow combining high yield with benefits for carbon sequestration and storage, production system stability under stress, and higher levels of animal and plant diversity.

MSU-DOE Plant Research Laboratory

Energy Technology Data Exchange (ETDEWEB)

1991-01-01

This document is the compiled progress reports of research funded through the Michigan State University/Department of Energy Plant Research Laboratory. Fourteen reports are included, covering the molecular basis of plant/microbe symbiosis, cell wall biosynthesis and proteins, gene expression, stress responses, plant hormone biosynthesis, interactions between the nuclear and organelle genomes, sensory transduction and tropisms, intracellular sorting and trafficking, regulation of lipid metabolism, molecular basis of disease resistance and plant pathogenesis, developmental biology of Cyanobacteria, and hormonal involvement in environmental control of plant growth. 320 refs., 26 figs., 3 tabs. (MHB)

Energy optimization methodology of multi-chiller plant in commercial buildings

International Nuclear Information System (INIS)

Thangavelu, Sundar Raj; Myat, Aung; Khambadkone, Ashwin

2017-01-01

This study investigates the potential energy savings in commercial buildings through optimized operation of a multi-chiller plant. The cooling load contributes 45–60% of total power consumption in commercial and office buildings, especially at tropics. The chiller plant operation is not optimal in most of the existing buildings because the chiller plant is either operated at design condition irrespective of the cooling load or optimized locally due to lack of overall chiller plant behavior. In this study, an overall energy model of chiller plant is developed to capture the thermal behavior of all systems and their interactions including the power consumption. An energy optimization methodology is proposed to derive optimized operation decisions for chiller plant at regular intervals based on building thermal load and weather condition. The benefits of proposed energy optimization methodology are examined using case study problems covering different chiller plant configurations. The case studies result confirmed the energy savings achieved through optimized operations is up to 40% for moderate size chiller plant and around 20% for small chiller plant which consequently reduces the energy cost and greenhouse gas emissions. - Highlights: • Energy optimization methodology improves the performance of multi-chiller plant. • Overall energy model of chiller plant accounts all equipment and the interactions. • Operation decisions are derived at regular interval based on time-varying factors. • Three case studies confirmed 20 to 40% of energy savings than conventional method.

Disturbance and Plant Succession in the Mojave and Sonoran Deserts of the American Southwest

Directory of Open Access Journals (Sweden)

Scott R. Abella

2010-03-01

Full Text Available Disturbances such as fire, land clearing, and road building remove vegetation and can have major influences on public health through effects on air quality, aesthetics, recreational opportunities, natural resource availability, and economics. Plant recovery and succession following disturbance are poorly understood in arid lands relative to more temperate regions. This study quantitatively reviewed vegetation reestablishment following a variety of disturbances in the Mojave and Sonoran Deserts of southwestern North America. A total of 47 studies met inclusion criteria for the review. The time estimated by 29 individual studies for full reestablishment of total perennial plant cover was 76 years. Although long, this time was shorter than an estimated 215 years (among 31 individual studies required for the recovery of species composition typical of undisturbed areas, assuming that recovery remains linear following the longest time since disturbance measurement made by the studies.

Produtividade e qualidade da uva 'Cabernet Sauvignon'produzida sob cobertura de plástico em cultivo orgânico Productivity and quality of grape 'Cabernet Sauvignon' produced in organic sistem under plastic covering

Directory of Open Access Journals (Sweden)

Alessandra Maria Detoni

2007-01-01

quality of the grape 'Cabernet Sauvignon' cultivated under covering of plastic in organic production system. The experiment was accomplished in an organic orchard in the west area of the state of Paraná; the plants were conducted in espalier system, with plastic covering in the planting line. It was evaluated tenor of soluble solids (SS, titrable acidity (TA, pH, total antocyanins, productivity, number of bunches for plant and medium bunch weight. They were not found significant differences in the tenor of SS (17.3ºBrix, however the fruits under the covering presented larger tenors of TA and pH, 1.14 g 100 mL-1 and 3.4 respectively, that those picked from plants without the plastic covering, which presented TA of 0.87 g 100 mL-1 and pH of 3.5. The largest tenor of total antocyanins was verified in the plants out of the covering, with 22.8 mg L-1. In the protected plants, the production was larger (1769 g plant-1 than in the plants without covering (492 g plant-1, which presented high index of diseases. It is concluded that the plastic covering makes possible the cultivation of grape 'Cabernet Sauvignon' in the organic production system, for providing a decrease in the incidence of diseases.

Spatiotemporal soil and saprolite moisture dynamics across a semi-arid woody plant gradient

Science.gov (United States)

Woody plant cover has increased 10-fold over the last 140+ years in many parts of the semi-arid western USA. Woody plant cover can alter the timing and amount of plant available moisture in the soil and saprolite. To assess spatiotemporal subsurface moisture dynamics over two water years in a snow-d...

Plant diversity and conservation in China: planning a strategic bioresource for a sustainable future.

Science.gov (United States)

Huang, Hongwen

2011-01-01

China is one of the richest countries for plant diversity with approximately 33 000 vascular plant species, ranking second in the world. However, the plant diversity in China is increasingly threatened, with an estimated 4000–5000 plant species being threatened or on the verge of extinction, making China, proportionally, one of the highest priorities for global plant biodiversity conservation. Coming in the face of the current ecological crisis, it is timely that China has launched China's Strategy for Plant Conservation (CSPC). China has increasingly recognized the importance of plant diversity in efforts to conserve and sustainably use its plant diversity. More than 3000 nature reserves have been established, covering approximately 16% of the land surface of China. These natural reserves play important roles in plant conservation, covering more than 85% of types of terrestrial natural ecosystems, 40% of types of natural wetlands, 20% of native forests and 65% of natural communities of vascular plants. Meanwhile, the flora conserved in botanical gardens is also extensive. A recent survey shows that the 10 largest botanical gardens have living collections of 43 502 taxa, with a total of 24 667 species in ex situ conservation. These provide an important reserve of plant resources for sustainable economic and social development in China. Plant diversity is the basis for bioresources and sustainable utilization. The 21st century is predicted to be an era of bio-economy driven by advances of bioscience and biotechnology. Bio-economy may become the fourth economy form after agricultural, industrial, and information and information technology economies, having far-reaching impacts on sustainable development in agriculture, forestry, environmental protection, light industry, food supply and health care and other micro-economy aspects. Thus, a strategic and forward vision for conservation of plant diversity and sustainable use of plant resources in the 21st century is of