Evaluation of emission of greenhouse gases from soils amended with sewage sludge.

Science.gov (United States)

Paramasivam, S; Fortenberry, Gamola Z; Julius, Afolabi; Sajwan, Kenneth S; Alva, A K

2008-02-01

Increase in concentrations of various greenhouse gases and their possible contributions to the global warming are becoming a serious concern. Anthropogenic activities such as cultivation of flooded rice and application of waste materials, such as sewage sludge which are rich in C and N, as soil amendments could contribute to the increase in emission of greenhouse gases such as methane (CH(4)) and nitrous oxide (N(2)O) into the atmosphere. Therefore, evaluation of flux of various greenhouse gases from soils amended with sewage sludge is essential to quantify their release into the atmosphere. Two soils with contrasting properties (Candler fine sand [CFS] from Florida, and Ogeechee loamy sand [OLS] from Savannah, GA) were amended with varying rates (0, 24.7, 49.4, 98.8, and 148.3 Mg ha(-1)) of 2 types of sewage sludge (industrial [ISS] and domestic [DSS] origin. The amended soil samples were incubated in anaerobic condition at field capacity soil water content in static chamber (Qopak bottles). Gas samples were extracted immediately after amending soils and subsequently on a daily basis to evaluate the emission of CH(4), CO(2) and N(2)O. The results showed that emission rates and cumulative emission of all three gases increased with increasing rates of amendments. Cumulative emission of gases during 25-d incubation of soils amended with different types of sewage sludge decreased in the order: CO(2) > N(2)O > CH(4). The emission of gases was greater from the soils amended with DSS as compared to that with ISS. This may indicate the presence of either low C and N content or possible harmful chemicals in the ISS. The emission of gases was greater from the CFS as compared to that from the OLS. Furthermore, the results clearly depicted the inhibitory effect of acetylene in both soils by producing more N(2)O and CH(4) emission compared to the soils that did not receive acetylene at the rate of 1 mL g(-1) soil. Enumeration of microbial population by fluorescein diacetate

Effect of freeze-thaw cycles on greenhouse gas fluxes from peat soils

Science.gov (United States)

Oh, H. D.; Rezanezhad, F.; Markelov, I.; McCarter, C. P. R.; Van Cappellen, P.

2017-12-01

The ongoing displacement of climate zones by global warming is increasing the frequency and intensity of freeze-thaw cycles in middle and high latitude regions, many of which are dominated by organic soils such as peat. Repeated freezing and thawing of soils changes their physical properties, geochemistry, and microbial community structure, which together govern the biogeochemical cycling of carbon and nutrients. In this presentation, we focus on how freeze-thaw cycles influence greenhouse gas fluxes from peat using a newly developed experimental soil column system that simulates realistic soil temperature profiles during freeze-thaw cycles. We measured the surface and subsurface changes to gas and aqueous phase chemistry to delineate the diffusion pathways and quantify soil greenhouse gas fluxes during freeze-thaw cycles using sulfur hexafluoride (SF6) as a conservative tracer. Three peat columns were assembled inside a temperature controlled chamber with different soil structures. All three columns were packed with 40 cm of undisturbed, slightly decomposed peat, where the soil of two columns had an additional 10 cm layer on top (one with loose Sphagnum moss and one with an impermeable plug). The results indicate that the release of SF6 and CO2 gas from the soil surface was influenced by the recurrent development of a physical ice barrier, which prevented gas exchange between the soil and atmosphere during freezing conditions. With the onset of thawing a pulse of SF6 and CO2 occurred, resulting in a flux of 3.24 and 2095.52 µmol/m2h, respectively, due to the build-up of gases in the liquid-phase pore space during freezing. Additionally, we developed a model to determine the specific diffusion coefficients for each peat column. These data allow us to better predict how increased frequency and intensity of freeze-thaw cycles will affect greenhouse gas emissions in northern peat soils.

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

Science.gov (United States)

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

2016-04-01

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

Soil greenhouse gas fluxes from different tree species on Taihang Mountain, North China

Science.gov (United States)

Liu, X. P.; Zhang, W. J.; Hu, C. S.; Tang, X. G.

2014-03-01

The objectives of this study were to investigate seasonal variation of greenhouse gas fluxes from soils on sites dominated by plantation (Robinia pseudoacacia, Punica granatum, and Ziziphus jujube) and natural regenerated forests (Vitex negundo var. heterophylla, Leptodermis oblonga, and Bothriochloa ischcemum), and to identify how tree species, litter exclusion, and soil properties (soil temperature, soil moisture, soil organic carbon, total N, soil bulk density, and soil pH) explained the temporal and spatial variation in soil greenhouse gas fluxes. Fluxes of greenhouse gases were measured using static chamber and gas chromatography techniques. Six static chambers were randomly installed in each tree species. Three chambers were randomly designated to measure the impacts of surface litter exclusion, and the remaining three were used as a control. Field measurements were conducted biweekly from May 2010 to April 2012. Soil CO2 emissions from all tree species were significantly affected by soil temperature, soil moisture, and their interaction. Driven by the seasonality of temperature and precipitation, soil CO2 emissions demonstrated a clear seasonal pattern, with fluxes significantly higher during the rainy season than during the dry season. Soil CH4 and N2O fluxes were not significantly correlated with soil temperature, soil moisture, or their interaction, and no significant seasonal differences were detected. Soil organic carbon and total N were significantly positively correlated with CO2 and N2O fluxes. Soil bulk density was significantly negatively correlated with CO2 and N2O fluxes. Soil pH was not correlated with CO2 and N2O emissions. Soil CH4 fluxes did not display pronounced dependency on soil organic carbon, total N, soil bulk density, and soil pH. Removal of surface litter significantly decreased in CO2 emissions and CH4 uptakes. Soils in six tree species acted as sinks for atmospheric CH4. With the exception of Ziziphus jujube, soils in all tree

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

DEFF Research Database (Denmark)

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

2012-01-01

Sandy soils, with low productivity, could be improved by compost application to sustain crop production. This study aimed to examine the effect of three compost types (vegetable, fruit and yard waste compost, garden waste compost, and spent mushroom compost) on basic properties of a loamy sand...... compost had greater effect in improving tomato productivity. A decade-long application of composts on loamy sand improved basic chemical and physical properties which were reflected in increased fruit yield in tomato. Since no negative effect of compost was observed, we suggest that sandy soils may serve...... and greenhouse tomato productivity. Disturbed and intact soil samples were taken from a decade-long compost field experiment on loamy sand with three compost types at application rate of 30 m3 ha-1 yr-1 (7.5 ton ha-1 yr-1). The soils were characterized for chemical and physical properties. Tomato was planted...

Pollution of intensively managed greenhouse soils by nutrients and heavy metals in the Yellow River Irrigation Region, Northwest China.

Science.gov (United States)

Kong, Xiaole; Cao, Jing; Tang, Rangyun; Zhang, Shengqiang; Dong, Fang

2014-11-01

The present study aimed to assess the potential ecological risk of heavy metals and nutrient accumulation in polytunnel greenhouse soils in the Yellow River irrigation region (YRIR), Northwest China, and to identify the potential sources of these heavy metals using principal component analysis. Contents of available nitrogen (AN), phosphorus (AP), and potassium (AK) in the surface polytunnel greenhouse soils (0-20 cm) varied from 13.42 to 486.78, from 39.10 to 566.97, and from 21.64 to 1,156.40 mg kg(-1), respectively, as well as AP, soil organic matter (SOM) and AK contents tended to increase significantly at the 0-20- and 20-40-cm soil layers. Heavy metal accumulations occurred in the polytunnel greenhouse soils as compared to arable soils, especially at a depth of 20 cm where Cd, Zn and Cu contents were significantly higher than arable soil. Cd and As were found to be the two main polluting elements in the greenhouse soils because their contents exceeded the thresholds established for greenhouse vegetable production HJ333-2006 in China and the background of Gansu province. It has been shown that Cd, Cu, Pb and Zn at the 0-20-cm soil layer were derived mainly from agricultural production activities, whereas contents of Cr and Ni at the same soil layer were determined by 'natural' factors and As originated from natural sources, deposition and irrigation water.

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

Directory of Open Access Journals (Sweden)

YIN Xing

2015-06-01

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

Dissipation and enantioselective degradation of plant growth retardants paclobutrazol and uniconazole in open field, greenhouse, and laboratory soils.

Science.gov (United States)

Wu, Chengwang; Sun, Jianqiang; Zhang, Anping; Liu, Weiping

2013-01-15

Greenhouses are increasingly important in human food supply. Pesticides used in greenhouses play important roles in horticulture; however, little is known about their behavior in greenhouse environments. This work investigates the dissipation and enantioselctive degradation of plant growth retardants including paclobutrazol and uniconazole in soils under three conditions (i.e., open field, greenhouse, and laboratory). The dissipation and enantioselective degradation of paclobutrazol and uniconazole in greenhouse were different from those in open field; they were more persistent in greenhouse than in open field soil. Leaching produced by rainfall is responsible for the difference in dissipation. Thus, local environmental impacts may occur more easily inside greenhouses, while groundwater may be more contaminated in open field. Spike concentrations of 5, 10, and 20 times the concentrations of native residues were tested for the enantioselective dissipation of the two pesticides; the most potent enantioselective degradation of paclobutrazol and uniconazole occurred at the 10 times that of the native residues in the greenhouse environments and at 20 times native residues in open field environments. The higher soil activity in greenhouses than in open fields was thought to be responsible for such a difference. The environmental risk and regulation of paclobutrazol and uniconazole should be considered at the enantiomeric level.

Using greenhouse gas fluxes to define soil functional types

Energy Technology Data Exchange (ETDEWEB)

Petrakis, Sandra; Barba, Josep; Bond-Lamberty, Ben; Vargas, Rodrigo

2017-12-04

Soils provide key ecosystem services and directly control ecosystem functions; thus, there is a need to define the reference state of soil functionality. Most common functional classifications of ecosystems are vegetation-centered and neglect soil characteristics and processes. We propose Soil Functional Types (SFTs) as a conceptual approach to represent and describe the functionality of soils based on characteristics of their greenhouse gas (GHG) flux dynamics. We used automated measurements of CO2, CH4 and N2O in a forested area to define SFTs following a simple statistical framework. This study supports the hypothesis that SFTs provide additional insights on the spatial variability of soil functionality beyond information represented by commonly measured soil parameters (e.g., soil moisture, soil temperature, litter biomass). We discuss the implications of this framework at the plot-scale and the potential of this approach at larger scales. This approach is a first step to provide a framework to define SFTs, but a community effort is necessary to harmonize any global classification for soil functionality. A global application of the proposed SFT framework will only be possible if there is a community-wide effort to share data and create a global database of GHG emissions from soils.

Soil Carbon Sequestration and the Greenhouse Effect (2nd Edition)

Science.gov (United States)

This volume is a second edition of the book “Soil Carbon Sequestration and The Greenhouse Effect”. The first edition was published in 2001 as SSSA Special Publ. #57. The present edition is an update of the concepts, processes, properties, practices and the supporting data. All chapters are new co...

The southern Brazilian grassland biome: soil carbon stocks, fluxes of greenhouse gases and some options for mitigation.

Science.gov (United States)

Pillar, V D; Tornquist, C G; Bayer, C

2012-08-01

The southern Brazilian grassland biome contains highly diverse natural ecosystems that have been used for centuries for grazing livestock and that also provide other important environmental services. Here we outline the main factors controlling ecosystem processes, review and discuss the available data on soil carbon stocks and greenhouse gases emissions from soils, and suggest opportunities for mitigation of climatic change. The research on carbon and greenhouse gases emissions in these ecosystems is recent and the results are still fragmented. The available data indicate that the southern Brazilian natural grassland ecosystems under adequate management contain important stocks of organic carbon in the soil, and therefore their conservation is relevant for the mitigation of climate change. Furthermore, these ecosystems show a great and rapid loss of soil organic carbon when converted to crops based on conventional tillage practices. However, in the already converted areas there is potential to mitigate greenhouse gas emissions by using cropping systems based on no soil tillage and cover-crops, and the effect is mainly related to the potential of these crop systems to accumulate soil organic carbon in the soil at rates that surpass the increased soil nitrous oxide emissions. Further modelling with these results associated with geographic information systems could generate regional estimates of carbon balance.

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

Science.gov (United States)

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

2017-03-01

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

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

Science.gov (United States)

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

2015-08-01

Phthalate esters (PAEs) are suspected of having adverse effects on human health and have been frequently detected in soils and vegetables. The present study investigated their occurrence and composition in plastic film greenhouse soil-vegetable systems and assessed their potential health risks to farmers exposed to these widespread pollutants. Six priority control phthalates, namely dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DnBP), butyl benzyl phthalate (BBP), di-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DnOP), were determined in 44 plastic film greenhouse vegetables and corresponding soils. Total PAEs ranged from 0.51 to 7.16mgkg(-1) in vegetables and 0.40 to 6.20mgkg(-1) in soils with average concentrations of 2.56 and 2.23mgkg(-1), respectively. DnBP, DEHP and DnOP contributed more than 90% of the total PAEs in both vegetables and soils but the proportions of DnBP and DnOP in vegetables were significantly (p3.00mgkg(-1) but were plastic film greenhouses. Health risks were mainly by exposure through vegetable consumption and soil ingestion. Copyright © 2015 Elsevier B.V. All rights reserved.

Longevity of terrestrial Carbon sinks: effects of soil degradation on greenhouse gas emissions

Science.gov (United States)

Kuhn, Nikolaus J.; Berger, Samuel; Kuonen, Samuel

2013-04-01

Soil erosion by water is a key process of soil and land degradation. In addition, significant amounts of nutrients and organic Carbon are moved from eroding source areas to landscape sinks. As a consequence, areas affected by erosion suffer a loss of fertility, while sinks experience the development of a stockpile of the deposited sediment, including soil organic matter and nutrients. The deposited nutrients are largely unavailable for the plants growing in these landscape sediment sinks once the thickness of the deposited layer is greater than the rooting depth of the plants. In addition, the deposited organic matter is decomposed slowly through the pack of sediment. At sites of erosion, nutrients have to be replaced and organic matter content of the soil declines due to a destruction of the A horizon. Over time, the risk of a significant reduction in productivity, for example caused by a loss of top soil with a sufficient water storage capacity for maximum plant growth, leads to a decline in CO2 uptake by photosynthesis. Soil organic matter at eroding sites therefore declines and consequently the sediment that is moved to landscape sinks also has a smaller organic matter content than sediment generated from the non-degraded soil. The sediment sinks, on the other hand, emit an increasing amount of greenhouse gases as a consequence of the increasing amount of organic matter deposited while the upslope area is eroded. Over time, the perceived sink effect of soil erosion for greenhouse gases is therefore replaced with a neutral or positive emission balance of erosion in agricultural landscapes. Such a switch from none or a negative emission balance of agricultural landscapes to a positive balance carries the risk of accelerating climate change. In this study, we tried to estimate the risk associated with ongoing soil degradation and closing landscape soil organic matter sinks. Currently observed global erosion rates were linked to known limitations of soil

Greenhouse gas emissions from a chinampa soil or floating gardens in Mexico

OpenAIRE

Ortiz-Cornejo, Nadia Livia; Luna-Guido, Marco; Rivera-Espinoza, Yadira; Vásquez-Murrieta, María Soledad; Ruíz-Valdiviezo, Víctor Manuel; Dendooven, Luc

2015-01-01

Agriculture in chinampas or 'floating gardens', is still found on the south of Mexico City, it is a high yield pre-Columbian cultivation system, which has soils enriched with organic matter. The objective of this research was to determine the greenhouse gas (GHG) emissions from a chinampa soil cultivated with amaranth (Amaranthus hypochondriacus L.), maize (Zea mays L.) or uncultivated. The soil was characterized and fluxes of GHG (CO2, N2O and CH4) were monitored for one year. The chinampa s...

Managing soil organic carbon in agriculture: the net effect on greenhouse gas emissions

International Nuclear Information System (INIS)

Marland, Gregg; West, Tristram O.; Schlamadinger, Bernhard; Canella, Lorenza

2003-01-01

A change in agricultural practice can increase carbon sequestration in agricultural soils. To know the net effect on greenhouse gas emissions to the atmosphere, however, we consider associated changes in CO 2 emissions resulting from the consumption of fossil fuels, emissions of other greenhouse gases and effects on land productivity and crop yield. We also consider how these factors will evolve over time. A change from conventional tillage to no-till agriculture, based on data for average practice in the U.S.; will result in net carbon sequestration in the soil that averages 337 kg C/ha/yr for the initial 20 yr with a decline to near zero in the following 20 yr, and continuing savings in CO 2 emissions because of reduced use of fossil fuels. The long-term results, considering all factors, can generally be expected to show decreased net greenhouse gas emissions. The quantitative details, however, depend on the site-specific impact of the conversion from conventional to no-till agriculture on agricultural yield and N 2 O emissions from nitrogen fertilizer

The regulatory role of endogenous iron on greenhouse gas emissions under intensive nitrogen fertilization in subtropical soils of China.

Science.gov (United States)

Han, Jiangpei; Shi, Liangsheng; Wang, Yakun; Chen, Zhuowei; Wu, Laosheng

2018-05-01

Anaerobic batch experiments were conducted to study the regulatory role of endogenous iron in greenhouse gas emissions under intensive nitrogen fertilization in subtropical soils of China. Fe 2+ , Fe 3+ , and NO 3 - -N dynamics and N 2 O, CH 4 , and CO 2 emissions, as well as the relationships between N fertilizer, endogenous iron, and greenhouse gas emissions were investigated. The emissions of N 2 O increased to different extents from all the test soils by N1 (260 mg N kg -1 ) application compared with N0. After 24 days of anaerobic incubation, the cumulative emissions of N 2 O from red soils in De'an (DR) were significantly higher than that from paddy soils in De'an (DP) and Qujialing (QP) under N1. However, N application enhanced CH 4 and CO 2 emissions from the red soils slightly but inhibited the emissions from paddy soils. The maximal CH 4 and CO 2 emission fluxes occurred in DP soil without N input. Pearson's correlation analysis showed that there were significant correlations (P greenhouse gas emissions mainly through the involvement in denitrification. The proportion of the electrons donated by Fe 2+ used for N 2 O production in denitrification in DP soil was approximately 37.53%. Moreover, positive correlations between Fe 2+ and CH 4 , CO 2 were found in both DR and QP soils, suggesting that endogenous iron might regulate the anaerobic decomposition of organic carbon to CH 4 and CO 2 in the two soils. Soil pH was also an important factor controlling greenhouse gas emissions by affecting endogenous iron availability and C and N transformation processes.

A carbon dioxide/methane greenhouse atmosphere on early Mars

Science.gov (United States)

Brown, L. L.; Kasting, J. F.

1993-01-01

One explanation for the formation of fluvial surface features on early Mars is that the global average surface temperature was maintained at or above the freezing point of water by the greenhouse warming of a dense CO2 atmosphere; however, Kasting has shown that CO2 alone is insufficient because the formation of CO2 clouds reduces the magnitude of the greenhouse effect. It is possible that other gases, such as NH3 and CH4, were present in the early atmosphere of Mars and contributed to the greenhouse effect. Kasting et al. investigated the effect of NH3 in a CO2 atmosphere and calculated that an NH3 mixing ratio of approximately 5 x 10 (exp -4) by volume, combined with a CO2 partial pressure of 4-5 bar, could generate a global average surface temperature of 273 K near 3.8 b.y. ago when the fluvial features are believed to have formed. Atmospheric NH3 is photochemically converted to N2 by ultraviolet radiation at wavelengths shortward of 230 nm; maintenance of sufficient NH3 concentrations would therefore require a source of NH3 to balance the photolytic destruction. We have used a one-dimensional photochemical model to estimate the magnitude of the NH3 source required to maintain a given NH3 concentration in a dense CO2 atmosphere. We calculate that an NH3 mixing ratio of 10(exp -4) requires a flux of NH3 on the order of 10(exp 12) molecules /cm-s. This figure is several orders of magnitude greater than estimates of the NH3 flux on early Mars; thus it appears that NH3 with CO2 is not enough to keep early Mars warm.

A Greenhouse Assay on the Effect of Applied Urea Amount on the Rhizospheric Soil Bacterial Communities.

Science.gov (United States)

Shang, Shuanghua; Yi, Yanli

2015-12-01

The rhizospheric bacteria play key role in plant nutrition and growth promotion. The effects of increased nitrogen inputs on plant rhizospheric soils also have impacted on whole soil microbial communities. In this study, we analyzed the effects of applied nitrogen (urea) on rhizospheric bacterial composition and diversity in a greenhouse assay using the high-throughput sequencing technique. To explore the environmental factors driving the abundance, diversity and composition of soil bacterial communities, the relationship between soil variables and the bacterial communities were also analyzed using the mantel test as well as the redundancy analysis. The results revealed significant bacterial diversity changes at different amounts of applied urea, especially between the control treatment and the N fertilized treatments. Mantel tests showed that the bacterial communities were significantly correlated with the soil nitrate nitrogen, available nitrogen, soil pH, ammonium nitrogen and total organic carbon. The present study deepened the understanding about the rhizospheric soil microbial communities under different amounts of applied urea in greenhouse conditions, and our work revealed the environmental factors affecting the abundance, diversity and composition of rhizospheric bacterial communities.

Study of soil-plant transfer of 226Ra under greenhouse conditions

International Nuclear Information System (INIS)

Soudek, Petr; Petrova, Sarka; Benesova, Dagmar; Kotyza, Jan; Vagner, Martin; Vankova, Radomira; Vanek, Tomas

2010-01-01

A soil-plant transfer study was performed using soil from a former uranium ore processing factory in South Bohemia. We present the results from greenhouse experiments which include estimates of the time required for phytoremediation. The accumulation of 226 Ra by different plant species from a mixture of garden soil and contaminated substrate was extremely variable, ranging from 0.03 to 2.20 Bq 226 Ra/g DW. We found differences in accumulation of 226 Ra between plants from the same genus and between cultivars of the same plant species. The results of 226 Ra accumulation showed a linear relation between concentration of 226 Ra in plants and concentration of 226 Ra in soil mixtures. On the basis of these results we estimated the time required for phytoremediation, but this appears to be too long for practical purposes.

An experimental study of soil temperature regimes associated with solar disinfestation techniques under greenhouse conditions in Greece.

Science.gov (United States)

Garofalakis, I; Tsiros, I; Frangoudakis, A; Chronopoulos, K; Flouri, F

2006-01-01

This paper deals with an experimental study of various techniques that have been applied for soil disinfestation purposes under greenhouse conditions. Various meteorological parameters and soil temperatures were measured for four different experimental soil segments (three associated with different disinfestation techniques and one as a reference) at depths varying between 0-1 m and with a time interval of 5 min in a greenhouse located in the Agricultural University of Athens Campus, Greece. Results showed that plastic polyethylene films such as covers, metallic conductors or a combination of both were able to enhance heat transfer and temperature increase in greenhouse soil. For typical disinfestation conditions, the depth-averaged temperature values for plastic covers, metallic conductors, and the combination of both were found to be higher than those for the reference of about 5 degrees C, 12 degrees C and 15 micro C, respectively. Moreover, the remained population percentages 50 days after the initiation of the experiment were found to be 19.3%, 25.3%, 37.3% Kcat 94% of the initial population, for the combination of metallic conductors and plastic covers, metallic conductors, plastic cover, and for the reference, respectively.

Greenhouse gas emissions from managed peat soils: is the IPCC reporting guidance realistic?

Directory of Open Access Journals (Sweden)

J. Couwenberg

2011-03-01

Full Text Available Drainage of peatlands leads to the decomposition of peat, resulting in substantial losses of carbon and nitrogen to the atmosphere. The conservation and restoration of peatlands can provide a major contribution to the mitigation of climate change. Improvements to guidance and capacity for reporting of greenhouse gas emissions from peatlands will be valuable in the context of the current negotiations towards a post-2012 climate agreement. This article evaluates IPCC approaches to greenhouse gas emissions from managed organic (peat soils and presents a summary table comparing IPCC default values with best estimates based on recent literature. Inconsistencies are pointed out with regard to the IPCC definitions of organic soils and climate zones. The 2006 IPCC Guidelines use a definition of organic soil that is not totally consistent with FAO definitions, use climate zones that are not fully compatible, present default CO2 values that are substantially (often an order of magnitude too low, and present a default N2O value for tropical cropland that is also an order of magnitude too low. An update of IPCC default values is desirable. The IPCC Emission Factor Database offers a platform for establishing more accurate emission factors, but so far contains little information about emissions from peat soils.

Microbial biomass, microbial diversity, soil carbon storage, and stability after incubation of soil from grass-clover pastures of different age

DEFF Research Database (Denmark)

Müller-Stöver, Dorette Sophie; Hauggaard-Nielsen, Henrik; Eriksen, Jørgen

2012-01-01

A laboratory incubation study with clover grass pasture soils of seven different ages (0, 1, 2, 3, 4, 5, and 16 production years) was carried out to determine initial soil carbon (C) and nitrogen (N) stocks and potentials for greenhouse gas emissions (N2O and CO2). Compared with the soil from...... the recently established pasture, an increase of total soil C and N was observed along with pasture age. Greenhouse gas emissions were low and not significantly different among the soils from younger pastures (0-5 years), but especially N2O emissions increased markedly in the soil from 16-year-old grass......-clover. Low emissions might mainly be due to an early C limitation occurring in the soils from younger pastures, which was also corroborated by decreasing levels of cold water-extractable C and early shifts within the microbial community. However, higher emissions from the old pasture soil were offset by its...

Effect of long-term organic fertilization on the soil pore characteristics of greenhouse vegetable fields converted from rice-wheat rotation fields.

Science.gov (United States)

Xu, L Y; Wang, M Y; Shi, X Z; Yu, Q B; Shi, Y J; Xu, S X; Sun, W X

2018-08-01

The shift from rice-wheat rotation (RWR) to greenhouse vegetable soils has been widely practiced in China. Several studies have discussed the changes in soil properties with land-use changes, but few studies have sought to address the differences in soil pore properties, especially for fields based on long-term organic fertilization under greenhouse vegetable system from RWR fields. This study uses the X-ray computed tomography (CT) scanning and statistical analysis to compare the long-term effects of the conversion of organic greenhouse vegetable fields (over one year, nine years, and fourteen years) from RWR fields on the soil macropore structure as well as the influencing factors from samples obtained in Nanjing, Jiangsu, China, using the surface soil layer and triplicate samples. The results demonstrated that the macropore structure became more complex and stable, with a higher connectivity, fractal dimension (FD) and a lower degree of anisotropy (DA), as the greenhouse vegetable planting time increased. The total topsoil macroporosity increased considerably, but the rate of increase gradually decelerated with time. The transmission pores (round pores ranging from 50 to 500μm) increased with time, but the biopores (>2000μm) clearly decreased after nine years of use as greenhouse vegetable fields. Soil organic matter (OM) has a significant relationship with the soil pore structure characteristics, especially for the transmission pores. In addition, organic fertilization on the topsoil had a short-term effect on the pores, but the effect stabilized and had a weak influence on the pores over longer periods. These results suggested that organic fertilization was conducive for controlling soil degradation regarding it physical quality for water and oxygen availability in the short term. Copyright © 2018 Elsevier B.V. All rights reserved.

The Effect of Soil Manganese on Japanese Larch (Larix Leptolepis Sieb. and Zucc.) Seedlings in the Greenhouse

Science.gov (United States)

Callie Jo Schweitzer; William E. Sharpe; Pamela J. Edwards

1999-01-01

Preliminary analysis of 9 year old Japanese larch trees and soil subjected to appliitions of triple ambient annual nitrogen (N) and sulfur (S) deposftfon revealed elevated available soil and foliar manganese (Mn) levels and decreased growth compared to controls. A greenhouse study was conducted in which Japanese larch seedlings were grown in geld collected soil...

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

Science.gov (United States)

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

2015-07-15

The occurrence of 15 antibiotics in soil and manure samples from 11 large-scale greenhouse vegetable production (GVP) bases in Beijing, China was investigated. Results showed that the greenhouse soils were ubiquitously contaminated with antibiotics, and that antibiotic concentrations were significantly higher in greenhouses than in open field soils. The mean concentrations of four antibiotic classes decreased in the following order: tetracyclines (102μg/kg)>quinolones (86μg/kg)>sulfonamides (1.1μg/kg)>macrolides (0.62μg/kg). This investigation also indicated that fertilization with manure and especially animal feces might be the primary source of antibiotics. A risk assessment based on the calculated risk quotients (RQs) demonstrated that oxytetracycline, chlortetracycline, norfloxacin, ciprofloxacin and enrofloxacin could pose a high risk to soil organisms. These results suggested that the ecological effects of antibiotic contamination in GVP bases and their potential adverse risks on human health need to be given special attention. Copyright © 2015 Elsevier B.V. All rights reserved.

Phytostabilization potential of two ecotypes of Vetiveria zizanioides in cadmium-contaminated soils: greenhouse and field experiments.

Science.gov (United States)

Phusantisampan, Theerawut; Meeinkuirt, Weeradej; Saengwilai, Patompong; Pichtel, John; Chaiyarat, Rattanawat

2016-10-01

Soil contamination by cadmium (Cd) poses a serious environmental and public health concern. Phytoremediation, i.e., the use of plants to remove contaminants from soil, has been proposed for treatment of Cd-contaminated ecosystems. In this study, we demonstrated the potential of Vetiveria zizanioides, commonly known as vetiver, to serve as an effective phytoremediation agent. Two ecotypes, i.e., India and Sri Lanka, were grown in greenhouse pots and in the field. Soils were amended with cow manure, pig manure, bat manure, and an organic fertilizer. Among all amendments, pig manure performed best in both greenhouse and field studies in terms of increasing total V. zizanioides biomass production in both ecotypes. In both greenhouse and in the field, tissue of the Sri Lanka ecotype had higher Cd concentrations than did the India ecotype. In the greenhouse, the presence of Cd did not affect total biomass production or root dry weight. The Sri Lanka ecotype had 2.7 times greater adventitious root numbers and 3.6 times greater Cd accumulation in roots than did the India ecotype. In the field study, the Sri Lanka ecotype offers potential as an excluder species, as it accumulated Cd primarily in roots, with translocation factor values 1 for all experiments except for the pig manure amendment. In addition, the highest Cd concentration in the Sri Lanka ecotype root (71.3 mg kg(-1)) was consistent with highest Cd uptake (10.4 mg plant(-1)) in the cow manure treatment. The India ecotype contained lower root Cd concentrations, and Cd accumulation was slightly higher in shoots compared to roots, with translocation factor (TF) values >1. The India ecotype was therefore not considered as an excluder in the Cd-contaminated soil. With the use of excluder species combined with application of organic amendments, soil contamination by Cd may be treated by alternative remediation methods such as phytostabilization.

Greenhouse gases fluxes and soil thermal properties in a pasture in central Missouri.

Science.gov (United States)

Nkonglolo, Nsalambi Vakanda; Johnson, Shane; Schmidt, Kent; Eivazi, Frieda

2010-01-01

Fluctuations of greenhouse gases emissions and soil properties occur at short spatial and temporal scales, however, results are often reported for larger scales studies. We monitored CO2, CH4, and N2O fluxes and soil temperature (T), thermal conductivity (K), resistivity (R) and thermal diffusivity (D) from 2004 to 2006 in a pasture. Soil air samples for determination of CO2, CH4 and N20 concentrations were collected from static and vented chambers and analyzed within two hours of collection with a gas chromatograph. T, K, R and D were measured in-situ using a KD2 probe. Soil samples were also taken for measurements of soil chemical and physical properties. The pasture acted as a sink in 2004, a source in 2005 and again a sink of CH4 in 2006. CO2 and CH4 were highest, but N2O as well as T, K and D were lowest in 2004. Only K was correlated with CO2 in 2004 while T correlated with both N2O (r = 0.76, p = 0.0001) and CO2 (r = 0.88, p = 0.0001) in 2005. In 2006, all gases fluxes were significantly correlated with T, K and R when the data for the entire year were considered. However, an in-depth examination of the data revealed the existence of month-to-month shifts, lack of correlation and differing spatial structures. These results stress the need for further studies on the relationship between soil properties and gases fluxes. K and R offer a promise as potential controlling factors for greenhouse gases fluxes in this pasture.

OSPW contamination transport through peat soils : laboratory and greenhouse study

Energy Technology Data Exchange (ETDEWEB)

Rezanezhad, F.; Price, J.S. [Waterloo Univ., ON (Canada). Dept. of Geography; Rochefort, L.; Pouliot, R. [Laval Univ., Quebec City, PQ (Canada). Dept. of Phytology; Andersen, R. [Laval Univ., Quebec City, PQ (Canada). Dept. of Phytology; Macaulay Land Use Research Inst., Aberdeen (United Kingdom); Daly, C. [Suncor Energy, Fort McMurray, AB (Canada)

2010-07-01

Large portions of northern Canada are covered by peatlands, and the majority of post-mined landscapes have increased salinity, heavy metals and naphthenic acids (NA). This PowerPoint presentation discussed laboratory and greenhouse studies conducted to determine oil sands process water (OSPW) contamination transport through peat soils. Peat is a highly complex porous media. The presence of sodium and NA has a toxic effect on aquatic life. Greenhouse studies were conducted to determine the changes caused by OSPW in the microbial community of a peat matrix over 2 growing seasons. The study showed that peat has an exceptional ability to absorb the contaminants in OSPW water. NA and sodium transport through peat was significantly delayed by sorption, and by diffusion into immobile water contained in the peat matrix. The vegetation in the study was healthy and tolerant to the contaminants in the OSPW. tabs., figs.

Impact Delivery of Reduced Greenhouse Gases on Early Mars

Science.gov (United States)

Haberle, R. M.; Zahnle, K. J.; Barlow, N. G.

2017-12-01

Reducing greenhouse gases are the latest trend in finding solutions to the early Mars climate dilemma. In thick CO2 atmospheres with modest concentrations of H2 and/or CH4, collision induced absorptions can reduce the outgoing long wave radiation enough to provide a significant greenhouse effect. To raise surface temperatures significantly by this process, surface pressures must be at least 500 mb and H2 and/or CH4 concentrations must be at or above the several percent level. Volcanism, serpentinization, and impacts are possible sources for reduced gases. Here we investigate the delivery of such gases by impact degassing from comets and asteroids. We use a time-marching stochastic impactor model that reproduces the observed crater size frequency distribution of Noachian surfaces. Following each impact, reduced gases are added to the atmosphere from a production function based on gas equilibrium calculations for several classes of meteorites and comets at typical post-impact temperatures. Escape and photochemistry then remove the reduced greenhouse gases continuously in time throughout each simulation. We then conduct an ensemble of simulations with this simple model varying the surface pressure, impact history, reduced gas production and escape functions, and mix of impactor types, to determine if this could be a potentially important part of the early Mars story. Our goal is to determine the duration of impact events that elevate reduced gas concentrations to significant levels and the total time of such events throughout the Noachian. Our initial simulations indicate that large impactors can raise H2 concentrations above the 10% level - a level high enough for a very strong greenhouse effect in a 1 bar CO2 atmosphere - for millions of years, and that the total time spent at or above that level can be in the 10's of millions of years range. These are interesting results that we plan to explore more thoroughly for the meeting.

Assessment and source identification of trace metals in the soils of greenhouse vegetable production in eastern China.

Science.gov (United States)

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

2013-11-01

Worldwide concern about the occurrence of trace metals in greenhouse vegetable production soils (GVPS) is growing. In this study, a total of 385 surface GVPS samples were collected in Shouguang and four vegetable production bases in Nanjing, Eastern China, for the determination of As and Hg using atomic fluorescence spectrometry and Pb, Cu, Cd, and Zn using inductively coupled plasma-mass spectrometry. Geo-accumulation indices and factor analysis were used to investigate the accumulation and sources of the trace metals in soils in Eastern China. The results revealed that greenhouse production practices increased accumulation of the trace metals, particularly Cd, Zn, and Cu in soils and their accumulation became significant with increasing years of cultivation. Accumulation of Cd and Zn was also found in soils from organic greenhouses. The GVPS was generally less polluted or moderately polluted by As, Cu, Zn, and Pb but heavily polluted by Cd and Hg in some locations. Overall, accumulation of Cd, Zn, and Cu in GVPS was primarily associated with anthropogenic activities, particularly, application of manure. The high level of Hg found in some sites was related to historical heavy application of Hg containing pesticides. However, further identification of Hg sources is needed. To reduce accumulation of the trace metals in GVPS, organic fertilizer application should be suggested through development and implementation of reasonable and sustainable strategies. © 2013 Elsevier Inc. All rights reserved.

Study of soil-plant transfer of {sup 226}Ra under greenhouse conditions

Energy Technology Data Exchange (ETDEWEB)

Soudek, Petr; Petrova, Sarka [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Drnovska 507, 161 06 Prague 6 (Czech Republic); Benesova, Dagmar; Kotyza, Jan [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Drnovska 507, 161 06 Prague 6 (Czech Republic); Faculty of Environment Technology, Institute of Chemical Technology, Technicka 5, 166 28 Prague 6 (Czech Republic); Vagner, Martin [Laboratory of Biologically Active Compounds, Institute of Experimental Botany AS CR, v.v.i., Rozvojova 263, Prague 6 (Czech Republic); Vankova, Radomira [Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany AS CR, v.v.i., Rozvojova 263, Prague 6 (Czech Republic); Vanek, Tomas, E-mail: vanek@ueb.cas.c [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Drnovska 507, 161 06 Prague 6 (Czech Republic)

2010-06-15

A soil-plant transfer study was performed using soil from a former uranium ore processing factory in South Bohemia. We present the results from greenhouse experiments which include estimates of the time required for phytoremediation. The accumulation of {sup 226}Ra by different plant species from a mixture of garden soil and contaminated substrate was extremely variable, ranging from 0.03 to 2.20 Bq {sup 226}Ra/g DW. We found differences in accumulation of {sup 226}Ra between plants from the same genus and between cultivars of the same plant species. The results of {sup 226}Ra accumulation showed a linear relation between concentration of {sup 226}Ra in plants and concentration of {sup 226}Ra in soil mixtures. On the basis of these results we estimated the time required for phytoremediation, but this appears to be too long for practical purposes.

Greenhouse gas emissions from agricultural soils in Austria

International Nuclear Information System (INIS)

Strebl, F.; Gebetsroither, E.; Orthofer, R.

2002-07-01

This report documents the calculations of anthropogenic greenhouse gas emissions in Austria of the IPCC-sector 'Agricultural Soils' for the period 1980 to 2001. According to available information, CH 4 emissions from agricultural soils are very small and thus irrelevant. N 2 O emissions were calculated according to the IPCC method; emission sources considered include direct emissions from nitrogen inputs to soils (mineral and organic fertilizers, crop residues, sewage sludge application, biological fixation) as well as indirect emissions (from atmospheric nitrogen deposition and nitrogen leaching) plus emissions from nitrogen input through grazing animal excreta. NH 3 and NO x emissions were calculated according to the CORINAIR method; sources considered were nitrogen inputs through fertilization as well as emissions from unfertilized cultures. In the year 1990 total emissions were 5.680 t N 2 O-N, 24.628 t NH 3 -N and 1.376 t NO x N. In the period 1980-2001 there were considerable fluctuations of emissions, caused by an inter annual variability of crop production and fertilizer consumption data. However, there are no significant emission trends in the past 20 years. Uncertainties were determined through a Monte-Carlo-based simulation; the standard deviation of a normal uncertainty distribution is 24 % for N 2 O, 13 % for NH 3 , and 18 % for NO x . (author)

Grazing reduces soil greenhouse gas fluxes in global grasslands: a meta-analysis

Science.gov (United States)

Tang, Shiming; Tian, Dashuan; Niu, Shuli

2017-04-01

Grazing causes a worldwide degradation in grassland and likely alters soil greenhouse gas fluxes (GHGs). However, the general patterns of grazing-induced changes in grassland soil GHGs and the underlying mechanisms remain unclear. Thus, we synthesized 63 independent experiments in global grasslands that examined grazing impacts on soil GHGs (CO2, CH4 and N2O). We found that grazing with light or moderate intensity did not significantly influence soil GHGs, but consistently depressed them under heavy grazing, reducing CO2 emission by 10.55%, CH4 uptake by 19.24% and N2O emission by 28.04%. The reduction in soil CO2 was mainly due to decreased activity in roots and microbes (soil respiration per unit root and microbial biomass), which was suppressed by less water availability due to higher soil temperature induced by lower community cover under heavy grazing. N2O emission decreased with grazing-caused decline in soil total N. The inhibitory effect on methanotroph activities by water stress is responsible for the decreased CH4 uptake. Furthermore, grazing duration and precipitation also influenced the direction and magnitude of responses in GHGs fluxes. Overall, our results indicate that the reduction in soil CO2 and N2O emission under heavy grazing is partially compensated by the decrease in CH4 uptake, which is mainly regulated by variations in soil moisture.

Greenhouse Gas Emissions from Brazilian Sugarcane Soils

Science.gov (United States)

Carmo, J.; Pitombo, L.; Cantarella, H.; Rosseto, R.; Andrade, C.; Martinelli, L.; Gava, G.; Vargas, V.; Sousa-Neto, E.; Zotelli, L.; Filoso, S.; Neto, A. E.

2012-04-01

Bioethanol from sugarcane is increasingly seen as a sustainable alternative energy source. Besides having high photosynthetic efficiency, sugarcane is a perennial tropical grass crop that can re-grow up to five or more years after being planted. Brazil is the largest producer of sugarcane in the world and management practices commonly used in the country lead to lower rates of inorganic N fertilizer application than sugarcane grown elsewhere, or in comparison to other feedstocks such as corn. Therefore, Brazilian sugarcane ethanol potentially promotes greenhouse gas savings. For that reason, several recent studies have attempted to assess emissions of greenhouse gases (GHG) during sugarcane production in the tropics. However, estimates have been mainly based on models due to a general lack of field data. In this study, we present data from in situ experiments on emission of three GHG (CO2, N2O, and CH4) in sugarcane fields in Brazil. Emissions are provided for sugarcane in different phases of the crop life cycle and under different management practices. Our results show that the use of nitrogen fertilizer in sugarcane crops resulted in an emission factor for N2O similar to those predicted by IPCC (1%), ranging from 0.59% in ratoon cane to 1.11% in plant cane. However, when vinasse was applied in addition to mineralN fertilizer, emissions of GHG increased in comparison to those from the use of mineral N fertilizer alone. Emissions increased significantly when experiments mimicked the accumulation of cane trash on the soil surface with 14 tons ha-1and 21 tons ha-1, which emission factor were 1.89% and 3.03%, respectively. This study is representative of Brazilian sugarcane systems under specific conditions for key factors affecting GHG emissions from soils. Nevertheless, the data provided will improve estimates of GHG from Brazilian sugarcane, and efforts to assess sugarcane ethanol sustainability and energy balance. Funding provided by the São Paulo Research

Mitigating yield-scaled greenhouse gas emissions through combined application of soil amendments: A comparative study between temperate and subtropical rice paddy soils

International Nuclear Information System (INIS)

Ali, Muhammad Aslam; Kim, P.J.; Inubushi, K.

2015-01-01

Effects of different soil amendments were investigated on methane (CH 4 ) and nitrous oxide (N 2 O) emissions, global warming potential (GWP) and yield scaled GWPs in paddy soils of Republic of Korea, Japan and Bangladesh. The experimental treatments were NPK only, NPK + fly ash, NPK + silicate slag, NPK + phosphogypsum(PG), NPK + blast furnace slag (BFS), NPK + revolving furnace slag (RFS), NPK + silicate slag (50%) + RFS (50%), NPK + biochar, NPK + biochar + Azolla-cyanobacteria, NPK + silicate slag + Azolla-cyanobacteria, NPK + phosphogypsum (PG) + Azolla-cyanobacteria. The maximum decrease in cumulative seasonal CH 4 emissions was recorded 29.7% and 32.6% with Azolla-cyanobacteria plus phospho-gypsum amendments in paddy soils of Japan and Bangladesh respectively, followed by 22.4% and 26.8% reduction with silicate slag plus Azolla-cyanobacteria application. Biochar amendments in paddy soils of Japan and Bangladesh decreased seasonal cumulative N 2 O emissions by 31.8% and 20.0% respectively, followed by 26.3% and 25.0% reduction with biochar plus Azolla-cyanobacteria amendments. Although seasonal cumulative CH 4 emissions were significantly increased by 9.5–14.0% with biochar amendments, however, global warming potentials were decreased by 8.0–12.0% with cyanobacterial inoculation plus biochar amendments. The maximum decrease in GWP was calculated 22.0–30.0% with Azolla-cyanobacteria plus silicate slag amendments. The evolution of greenhouse gases per unit grain yield (yield scaled GWP) was highest in the NPK treatment, which was decreased by 43–50% from the silicate slag and phosphogypsum amendments along with Azolla-cyanobacteria inoculated rice planted soils. Conclusively, it is recommended to incorporate Azolla-cyanobacteria with inorganic and organic amendments for reducing GWP and yield scaled GWP from the rice planted paddy soils of temperate and subtropical countries. - Highlights: • Azolla-cyanobacteria with organic and inorganic amendments

Composting of biochars improves their sorption properties, retains nutrients during composting and affects greenhouse gas emissions after soil application

Science.gov (United States)

Biochar application to soils has been suggested to elevate nutrient sorption, improve soil fertility and reduce net greenhouse gas (GHG) emissions. We examined the impact of composting biochar together with a biologically active substrate (i.e., livestock manure-straw mixture). We hypothesized that ...

A Worldwide Assessment of Greenhouse Gas Emissions from Drained Organic Soils

Directory of Open Access Journals (Sweden)

Francesco Nicola Tubiello

2016-04-01

Full Text Available Despite the importance of organic soils, including peatlands, in the global carbon cycle, detailed information on regional and global emissions is scarce. This is due to the difficulty to map, measure, and assess the complex dynamics of land, soil, and water interactions needed to assess the human-driven degradation of organic soils. We produced a new methodology for the comprehensive assessment of drained organic soils in agriculture and the estimation of the associated greenhouse gas emissions. Results indicated that over 25 million hectares of organic soils were drained worldwide for agriculture use, of which about 60% were in boreal and temperate cool areas, 34% in tropical areas, and 5% in warm temperate areas. Total emissions from the drainage were globally significant, totaling nearly one billion tonnes CO2eq annually. Of this, the CO2 component, about 780 million tonnes, represented more than one-fourth of total net CO2 emissions from agriculture, forestry, and land use. The bulk of these emissions came from a few tropical countries in Southeast Asia, and was linked to land clearing and drainage for crop cultivation. Geospatial data relative to this work were disseminated via the FAO geospatial server GeoNetwork, while the national aggregated statistics were disseminated via the FAOSTAT database.

Agricultural greenhouse with storage of sensible and latent heat in the soil. Modeling and simulation of thermal and hydric transfer. Experimental validation

Energy Technology Data Exchange (ETDEWEB)

Al Cheikh Kassem, N.; Miriel, J.; Roux, A. [Institut National des Sciences Appliquees (INSA), 35 - Rennes (France)

1993-12-31

This work presents a simulation model of sensible and latent heat storage in the soil of an agricultural greenhouse. Results recorded by the laboratory device of grounded storage and thermo-physic parameter values of soil experimentally obtained by a three rod thermal shock probe are used for checking the simulation model and thus assessing the performance of such a system and the coupling between the greenhouse and the storage. (Authors). 3 refs., 6 figs.

Soil Carbon Chemistry and Greenhouse Gas Production in Global Peatlands

Science.gov (United States)

Normand, A. E.; Turner, B. L.; Lamit, L. J.; Smith, A. N.; Baiser, B.; Clark, M. W.; Hazlett, C.; Lilleskov, E.; Long, J.; Grover, S.; Reddy, K. R.

2017-12-01

Peatlands play a critical role in the global carbon cycle because they contain approximately 30% of the 1500 Pg of carbon stored in soils worldwide. However, the stability of these vast stores of carbon is under threat from climate and land-use change, with important consequences for global climate. Ecosystem models predict the impact of peatland perturbation on carbon fluxes based on total soil carbon pools, but responses could vary markedly depending on the chemical composition of soil organic matter. Here we combine experimental and observational studies to quantify the chemical nature and response to perturbation of soil organic matter in peatlands worldwide. We quantified carbon functional groups in a global sample of 125 freshwater peatlands using solid-state 13C nuclear magnetic resonance (NMR) spectroscopy to determine the drivers of molecular composition of soil organic matter. We then incubated a representative subset of the soils under aerobic and anaerobic conditions to determine how organic matter composition influences carbon dioxide (CO2) and methane (CH4) emissions following drainage or flooding. The functional chemistry of peat varied markedly at large and small spatial scales, due to long-term land use change, mean annual temperature, nutrient status, and vegetation, but not pH. Despite this variation, we found predictable responses of greenhouse gas production following drainage based on soil carbon chemistry, defined by a novel Global Peat Stability Index, with greater CO2 and CH4 fluxes from soils enriched in oxygen-containing organic carbon (O-alkyl C) and depleted in aromatic and hydrophobic compounds. Incorporation of the Global Peat Stability Index of peatland organic matter into earth system models and management strategies, which will improve estimates of GHG fluxes from peatlands and ultimately advance management to reduce carbon loss from these sensitive ecosystems.

Early Cretaceous greenhouse pumped higher taxa diversification in spiders.

Science.gov (United States)

Shao, Lili; Li, Shuqiang

2018-05-24

The Cretaceous experienced one of the most remarkable greenhouse periods in geological history. During this time, ecosystem reorganizations significantly impacted the diversification of many groups of organisms. The rise of angiosperms marked a major biome turnover. Notwithstanding, relatively little remains known about how the Cretaceous global ecosystem impacted the evolution of spiders, which constitute one of the most abundant groups of predators. Herein, we evaluate the transcriptomes of 91 taxa representing more than half of the spider families. We add 23 newly sequenced taxa to the existing database to obtain a robust phylogenomic assessment. Phylogenetic reconstructions using different datasets and methods obtain novel placements of some groups, especially in the Synspermiata and the group having a retrolateral tibial apophysis (RTA). Molecular analyses indicate an expansion of the RTA clade at the Early Cretaceous with a hunting predatory strategy shift. Fossil analyses show a 7-fold increase of diversification rate at the same period, but this likely owes to the first occurrences spider in amber deposits. Additional analyses of fossil abundance show an accumulation of spider lineages in the Early Cretaceous. We speculate that the establishment of a warm greenhouse climate pumped the diversification of spiders, in particular among webless forms tracking the abundance of insect prey. Our study offers a new pathway for future investigations of spider phylogeny and diversification. Copyright © 2018. Published by Elsevier Inc.

Estimation of net greenhouse gas balance using crop- and soil-based approaches: Two case studies

International Nuclear Information System (INIS)

Huang, Jianxiong; Chen, Yuanquan; Sui, Peng; Gao, Wansheng

2013-01-01

The net greenhouse gas balance (NGHGB), estimated by combining direct and indirect greenhouse gas (GHG) emissions, can reveal whether an agricultural system is a sink or source of GHGs. Currently, two types of methods, referred to here as crop-based and soil-based approaches, are widely used to estimate the NGHGB of agricultural systems on annual and seasonal crop timescales. However, the two approaches may produce contradictory results, and few studies have tested which approach is more reliable. In this study, we examined the two approaches using experimental data from an intercropping trial with straw removal and a tillage trial with straw return. The results of the two approaches provided different views of the two trials. In the intercropping trial, NGHGB estimated by the crop-based approach indicated that monocultured maize (M) was a source of GHGs (− 1315 kg CO 2 −eq ha −1 ), whereas maize–soybean intercropping (MS) was a sink (107 kg CO 2 −eq ha −1 ). When estimated by the soil-based approach, both cropping systems were sources (− 3410 for M and − 2638 kg CO 2 −eq ha −1 for MS). In the tillage trial, mouldboard ploughing (MP) and rotary tillage (RT) mitigated GHG emissions by 22,451 and 21,500 kg CO 2 −eq ha −1 , respectively, as estimated by the crop-based approach. However, by the soil-based approach, both tillage methods were sources of GHGs: − 3533 for MP and − 2241 kg CO 2 −eq ha −1 for RT. The crop-based approach calculates a GHG sink on the basis of the returned crop biomass (and other organic matter input) and estimates considerably more GHG mitigation potential than that calculated from the variations in soil organic carbon storage by the soil-based approach. These results indicate that the crop-based approach estimates higher GHG mitigation benefits compared to the soil-based approach and may overestimate the potential of GHG mitigation in agricultural systems. - Highlights: • Net greenhouse gas balance (NGHGB) of

Land Use, Land Use History, and Soil Type Affect Soil Greenhouse Gas Fluxes From Agricultural Landscapes of the East African Highlands

Science.gov (United States)

Wanyama, I.; Rufino, M. C.; Pelster, D. E.; Wanyama, G.; Atzberger, C.; van Asten, P.; Verchot, Louis V.; Butterbach-Bahl, K.

2018-03-01

This study aims to explain effects of soil textural class, topography, land use, and land use history on soil greenhouse gas (GHG) fluxes in the Lake Victoria region. We measured GHG fluxes from intact soil cores collected in Rakai, Uganda, an area characterized by low-input smallholder (soil cores were air dried and rewetted to water holding capacities (WHCs) of 30, 55, and 80%. Soil CO2, CH4, and N2O fluxes were measured for 48 h following rewetting. Cumulative N2O fluxes were highest from soils under perennial crops and the lowest from soils under annual crops (P soils had lower N2O fluxes than the clay soils (P soil CO2 fluxes were highest from eucalyptus plantations and lowest from annual crops across multiple WHC (P = 0.014 at 30% WHC and P soil cores from the top soil. This study reveals that land use and soil type have strong effects on GHG fluxes from agricultural land in the study area. Field monitoring of fluxes is needed to confirm whether these findings are consistent with what happens in situ.

Predicting greenhouse gas emissions and soil carbon from changing pasture to an energy crop.

Directory of Open Access Journals (Sweden)

Benjamin D Duval

Full Text Available Bioenergy related land use change would likely alter biogeochemical cycles and global greenhouse gas budgets. Energy cane (Saccharum officinarum L. is a sugarcane variety and an emerging biofuel feedstock for cellulosic bio-ethanol production. It has potential for high yields and can be grown on marginal land, which minimizes competition with grain and vegetable production. The DayCent biogeochemical model was parameterized to infer potential yields of energy cane and how changing land from grazed pasture to energy cane would affect greenhouse gas (CO2, CH4 and N2O fluxes and soil C pools. The model was used to simulate energy cane production on two soil types in central Florida, nutrient poor Spodosols and organic Histosols. Energy cane was productive on both soil types (yielding 46-76 Mg dry mass · ha(-1. Yields were maintained through three annual cropping cycles on Histosols but declined with each harvest on Spodosols. Overall, converting pasture to energy cane created a sink for GHGs on Spodosols and reduced the size of the GHG source on Histosols. This change was driven on both soil types by eliminating CH4 emissions from cattle and by the large increase in C uptake by greater biomass production in energy cane relative to pasture. However, the change from pasture to energy cane caused Histosols to lose 4493 g CO2 eq · m(-2 over 15 years of energy cane production. Cultivation of energy cane on former pasture on Spodosol soils in the southeast US has the potential for high biomass yield and the mitigation of GHG emissions.

Greenhouses and their humanizing synergies

Science.gov (United States)

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

2014-03-01

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

Freeze-Thaw Cycles and Soil Biogeochemistry: Implications for Greenhouse Gas emission

Science.gov (United States)

Rezanezhad, F.; Milojevic, T.; Oh, D. H.; Parsons, C. T.; Smeaton, C. M.; Van Cappellen, P.

2016-12-01

Freeze-thaw cycles represent a major natural climate forcing acting on soils at middle and high latitudes. Repeated freezing and thawing of soils changes their physical properties, geochemistry, and microbial community structure, which together govern the biogeochemical cycling of carbon and nutrients. In this presentation, we focus on how freeze-thaw cycles regulate carbon and nitrogen cycling and how these transformations influence greenhouse gas (GHG) fluxes. We present a novel approach, which combines the acquisition of physical and chemical data in a newly developed experimental soil column system. This system simulates realistic soil temperature profiles during freeze-thaw cycles. A high-resolution, Multi-Fiber Optode (MuFO) microsensor technique was used to detect oxygen (O2) continuously in the column at multiple depths. Surface and subsurface changes to gas and aqueous phase chemistry were measured to delineate the pathways and quantify soil respiration rates during freeze-thaw cycles. The results indicate that the time-dependent release of GHG from the soil surface is influenced by a combination of two key factors. Firstly, fluctuations in temperature and O2 availability affect soil biogeochemical activity and GHG production. Secondly, the recurrent development of a physical ice barrier prevents exchange of gaseous compounds between the soil and atmosphere during freezing conditions; removal of this barrier during thaw conditions increases GHG fluxes. During freezing, O2 levels in the unsaturated zone decreased due to restricted gas exchange with the atmosphere. As the soil thawed, O2 penetrated deeper into the soil enhancing the aerobic mineralization of organic carbon and nitrogen. Additionally, with the onset of thawing a pulse of gas flux occurred, which is attributed to the build-up of respiratory gases in the pore space during freezing. The latter implies enhanced anaerobic respiration as O2 supply ceases when the upper soil layer freezes.

Greenhouse study on the phytoremediation potential of vetiver grass, Chrysopogon zizanioides L., in arsenic-contaminated soils.

Science.gov (United States)

Datta, Rupali; Quispe, Mario A; Sarkar, Dibyendu

2011-01-01

The purpose of this greenhouse study was to assess the capacity of vetiver grass to accumulate arsenic from pesticide-contaminated soils of varying physico-chemical properties. Results indicate that vetiver is capable of tolerating moderate levels of arsenic up to 225 mg/kg. Plant growth and arsenic removal efficiency was strongly influenced by soil properties. Arsenic removal was highest (10.6%) in Millhopper soil contaminated with 45 mg/kg arsenic, which decreased to 4.5 and 0.6% at 225 and 450 mg/kg, respectively. High biomass, widespread root system and environmental tolerance make this plant an attractive choice for the remediation of soils contaminated with moderate levels of arsenic.

A validated physical model of greenhouse climate

International Nuclear Information System (INIS)

Bot, G.P.A.

1989-01-01

In the greenhouse model the momentaneous environmental crop growth factors are calculated as output, together with the physical behaviour of the crop. The boundary conditions for this model are the outside weather conditions; other inputs are the physical characteristics of the crop, of the greenhouse and of the control system. The greenhouse model is based on the energy, water vapour and CO 2 balances of the crop-greenhouse system. While the emphasis is on the dynamic behaviour of the greenhouse for implementation in continuous optimization, the state variables temperature, water vapour pressure and carbondioxide concentration in the relevant greenhouse parts crop, air, soil and cover are calculated from the balances over these parts. To do this in a proper way, the physical exchange processes between the system parts have to be quantified first. Therefore the greenhouse model is constructed from submodels describing these processes: a. Radiation transmission model for the modification of the outside to the inside global radiation. b. Ventilation model to describe the ventilation exchange between greenhouse and outside air. c. The description of the exchange of energy and mass between the crop and the greenhouse air. d. Calculation of the thermal radiation exchange between the various greenhouse parts. e. Quantification of the convective exchange processes between the greenhouse air and respectively the cover, the heating pipes and the soil surface and between the cover and the outside air. f. Determination of the heat conduction in the soil. The various submodels are validated first and then the complete greenhouse model is verified

Effects of Biochar on the Net Greenhouse Gas Emissions under Continuous Flooding and Water-Saving Irrigation Conditions in Paddy Soils

Directory of Open Access Journals (Sweden)

Le Qi

2018-05-01

Full Text Available In this study, we investigated the greenhouse gas emission under different application of biochar in the conditions of continuous flooding and water-saving irrigation in paddy fields, whereas, plant and soil carbon sequestration were considered in the calculation of net greenhouse gas emissions. The emission rates of methane (CH4, carbon dioxide (CO2, and nitrous oxide (N2O gases were simultaneously monitored once every 7–10 days using the closed-chamber method. As a whole, the net greenhouse gas emission in the water-saving irrigation was more than that of the continuous flooding irrigation conditions. Compared with the water-saving irrigation, the continuous flooding irrigation significantly increased the CH4 in the control (CK and chemical fertilizer treatments (NPK. The CO2 emissions increased in each treatment of the water-saving irrigation condition, especially in the chemical fertilizer treatments (NPKFW. Similarly, the soil N2O emission was very sensitive to the water-saving irrigation condition. An interesting finding is that the biochar application in soils cut down the soil N2O emission more significantly than NPKFW in the water-saving irrigation condition while the effect of biochar increased under the continuous flooding irrigation condition.

Changes in soil bacterial community structure as a result of incorporation of Brassica plants compared with continuous planting eggplant and chemical disinfection in greenhouses.

Science.gov (United States)

Li, Tianzhu; Liu, Tongtong; Zheng, Chengyu; Kang, Chunsheng; Yang, Zichao; Yao, Xiaotong; Song, Fengbin; Zhang, Runzhi; Wang, Xuerong; Xu, Ning; Zhang, Chunyi; Li, Wei; Li, Shumin

2017-01-01

Greenhouse eggplant monocropping in China has contributed to the aggravation of soil-borne diseases, reductions in crop quality and yield, and the degradation of physical and chemical soil properties. Crop rotation is one effective way of alleviating the problems of continuous cropping worldwide; however, few studies have reported changes in soil bacterial community structures and physical and chemical soil properties after Brassica vegetables had been rotated with eggplant in greenhouses. In this experiment, mustard-eggplant (BFN) and oilseed rape-eggplant (BFC) rotations were studied to identify changes in the physicochemical properties and bacterial community structure in soil that was previously subject to monocropping. Samples were taken after two types of Brassica plants incorporated into soil for 15 days to compare with continually planted eggplant (control, CN) and chemical disinfection of soil (CF) in greenhouses. MiSeq pyrosequencing was used to analyze soil bacterial diversity and structure in the four different treatments. A total of 55,129 reads were identified, and rarefaction analysis showed that the soil treatments were equally sampled. The bacterial richness of the BFC treatment and the diversity of the BFN treatment were significantly higher than those of the other treatments. Further comparison showed that the bacterial community structures of BFC and BFN treatments were also different from CN and CF treatments. The relative abundance of several dominant bacterial genera in the BFC and BFN treatments (such as Flavobacteria, Stenotrophomonas, Massilia and Cellvibrio, which played different roles in improving soil fertility and advancing plant growth) was distinctly higher than the CN or CF treatments. Additionally, the total organic matter and Olsen-P content of the BFC and BFN treatments were significantly greater than the CN treatment. We conclude that Brassica vegetables-eggplant crop rotations could provide a more effective means of solving

Mitigating yield-scaled greenhouse gas emissions through combined application of soil amendments: A comparative study between temperate and subtropical rice paddy soils

Energy Technology Data Exchange (ETDEWEB)

Ali, Muhammad Aslam, E-mail: litonaslam@yahoo.com [Dept. of Environmental Science, Bangladesh Agricultural University, Mymensingh 2202 (Bangladesh); Dept. of Agricultural Chemistry, Gyeongsang National University, Jinju (Korea, Republic of); Division of Environmental Horticulture, Chiba University, Matsudo, Chiba 271-8510 (Japan); Kim, P.J., E-mail: pjkim@nongae.gsnu.ac.kr [Dept. of Agricultural Chemistry, Gyeongsang National University, Jinju (Korea, Republic of); Inubushi, K. [Division of Environmental Horticulture, Chiba University, Matsudo, Chiba 271-8510 (Japan)

2015-10-01

Effects of different soil amendments were investigated on methane (CH{sub 4}) and nitrous oxide (N{sub 2}O) emissions, global warming potential (GWP) and yield scaled GWPs in paddy soils of Republic of Korea, Japan and Bangladesh. The experimental treatments were NPK only, NPK + fly ash, NPK + silicate slag, NPK + phosphogypsum(PG), NPK + blast furnace slag (BFS), NPK + revolving furnace slag (RFS), NPK + silicate slag (50%) + RFS (50%), NPK + biochar, NPK + biochar + Azolla-cyanobacteria, NPK + silicate slag + Azolla-cyanobacteria, NPK + phosphogypsum (PG) + Azolla-cyanobacteria. The maximum decrease in cumulative seasonal CH{sub 4} emissions was recorded 29.7% and 32.6% with Azolla-cyanobacteria plus phospho-gypsum amendments in paddy soils of Japan and Bangladesh respectively, followed by 22.4% and 26.8% reduction with silicate slag plus Azolla-cyanobacteria application. Biochar amendments in paddy soils of Japan and Bangladesh decreased seasonal cumulative N{sub 2}O emissions by 31.8% and 20.0% respectively, followed by 26.3% and 25.0% reduction with biochar plus Azolla-cyanobacteria amendments. Although seasonal cumulative CH{sub 4} emissions were significantly increased by 9.5–14.0% with biochar amendments, however, global warming potentials were decreased by 8.0–12.0% with cyanobacterial inoculation plus biochar amendments. The maximum decrease in GWP was calculated 22.0–30.0% with Azolla-cyanobacteria plus silicate slag amendments. The evolution of greenhouse gases per unit grain yield (yield scaled GWP) was highest in the NPK treatment, which was decreased by 43–50% from the silicate slag and phosphogypsum amendments along with Azolla-cyanobacteria inoculated rice planted soils. Conclusively, it is recommended to incorporate Azolla-cyanobacteria with inorganic and organic amendments for reducing GWP and yield scaled GWP from the rice planted paddy soils of temperate and subtropical countries. - Highlights: • Azolla-cyanobacteria with organic and

Warming Early Mars by Impact Degassing of Reduced Greenhouse Gases

Science.gov (United States)

Haberle, R. M.; Zahnle, K.; Barlow, N. G.

2018-01-01

Reducing greenhouse gases are once again the latest trend in finding solutions to the early Mars climate dilemma. In its current form collision induced absorptions (CIA) involving H2 and/or CH4 provide enough extra greenhouse power in a predominately CO2 atmosphere to raise global mean surface temperatures to the melting point of water provided the atmosphere is thick enough and the reduced gases are abundant enough. Surface pressures must be at least 500 mb and H2 and/or CH4 concentrations must be at or above the several percent level for CIA to be effective. Atmospheres with 1-2 bars of CO2 and 2- 10% H2 can sustain surface environments favorable for liquid water. Smaller concentrations of H2 are sufficient if CH4 is also present. If thick CO2 atmospheres with percent level concentrations of reduced gases are the solution to the faint young Sun paradox for Mars, then plausible mechanisms must be found to generate and sustain the gases. Possible sources of reducing gases include volcanic outgassing, serpentinization, and impact delivery; sinks include photolyis, oxidation, and escape to space. The viability of the reduced greenhouse hypothesis depends, therefore, on the strength of these sources and sinks. In this paper we focus on impact delivered reduced gases.

Impacts of prescribed burning on soil greenhouse gas fluxes in a suburban native forest of south-eastern Queensland, Australia

Science.gov (United States)

Zhao, Y.; Wang, Y. Z.; Xu, Z. H.; Fu, L.

2015-11-01

Prescribed burning is a forest management practice that is widely used in Australia to reduce the risk of damaging wildfires. Prescribed burning can affect both carbon (C) and nitrogen (N) cycling in the forest and thereby influence the soil-atmosphere exchange of major greenhouse gases, i.e. carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). To quantify the impact of a prescribed burning (conducted on 27 May 2014) on greenhouse gas exchange and the potential controlling mechanisms, we carried out a series of field measurements before (August 2013) and after (August 2014 and November 2014) the fire. Gas exchange rates were determined in four replicate plots which were burned during the combustion and in another four adjacent unburned plots located in green islands, using a set of static chambers. Surface soil properties including temperature, pH, moisture, soil C and N pools were also determined either by in situ measurement or by analysing surface 10 cm soil samples. All of the chamber measurements indicated a net sink of atmospheric CH4, with mean CH4 uptake ranging from 1.15 to 1.99 mg m-2 d-1. Prescribed burning significantly enhanced CH4 uptake as indicated by the significant higher CH4 uptake rates in the burned plots measured in August 2014. In the following 3 months, the CH4 uptake rate was recovered to the pre-burning level. Mean CO2 emission from the forest soils ranged from 2721.76 to 7113.49 mg m-2 d-1. The effect of prescribed burning on CO2 emission was limited within the first 3 months, as no significant difference was observed between the burned and the adjacent unburned plots in both August and November 2014. The CO2 emissions showed more seasonal variations, rather than the effects of prescribed burning. The N2O emission in the plots was quite low, and no significant impact of prescribed burning was observed. The changes in understory plants and litter layers, surface soil temperature, C and N substrate availability and microbial

Response of greenhouse gas emissions from three types of wetland soils to simulated temperature change on the Qinghai-Tibetan Plateau

Science.gov (United States)

Liu, Yi; Liu, Guihua; Xiong, Ziqian; Liu, Wenzhi

2017-12-01

Wetlands emit a large quantity of greenhouse gases into the atmosphere and contribute significantly to global warming. The Qinghai-Tibetan Plateau, known as the ;Third Pole; of the earth, contains abundant and diverse wetlands. Due to increasing human-induced pressures such as reclamation, overgrazing and climate change, many plateau wetlands have been degraded or destroyed. Until now, the response of soil greenhouse gas emissions to extreme summer temperatures in the plateau wetlands remains unknown. In this study, we collected 36 soil samples from riverine, lacustrine and palustrine wetlands on the Qinghai-Tibetan Plateau. We compared the carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) emissions from soils incubated aerobically at 7, 12, and 19 °C. The results showed that the emissions of CH4 and N2O but not CO2 were significantly affected by the simulated temperature change. The N2O emission rate was considerably higher in palustrine wetlands compared with lacustrine and riverine wetlands. However, the CO2 and CH4 emissions did not differ significantly among the three wetland types. The ratio of CO2 to CH4 production increased with increasing incubation temperatures. The global warming potential of greenhouse gases at 19 °C was approximately 1.18 and 2.12 times greater than that at 12 and 7 °C, respectively. Our findings suggest that temperature change has a strong effect on soil greenhouse gas emissions and global warming potential of wetlands on the Qinghai-Tibetan Plateau, especially palustrine wetlands. Therefore, targeted strategies should be developed to mitigate the potential impacts of climate warming on the plateau.

Effect of greenhouse micro-climate on the selected summer vegetables

International Nuclear Information System (INIS)

Sethi, V.P.; Lal, T.; Gupta, Y.P.; Hans, V.S.

2003-01-01

The study deals with creating suitable environment for the germination and subsequent growth of plants in the greenhouse of size 7 m x 3 m x 2 m for raising early summer vegetable nursery. It was observed that the average air temperature inside the greenhouse was 10–12°C higher than the ambient air temperature. Inside average soil temperature was also 5–7°C higher than the corresponding temperature outside the greenhouse. Greenhouse night micro-climate was modified by covering its roof with a polyester sheet to cut down the effect of night sky radiation thereby raising the inside minimum temperature. The effect of elevated temperature was monitored on the germination and subsequent growth of “muskmelon” seedlings up to two true leaf stage. It was observed that the germination of seeds, sown inside the greenhouse occurred one week earlier as compared to the seeds sown in the open field. The rate of growth of the seedlings inside the greenhouse took only three weeks to attain two-leaf stage, whereas seedlings sown in the open field took five weeks to reach up to two-leaf stage. Thus, there was a clear saving of 15 days in raising the nursery under the greenhouse. (author)

Studies on the under ground heating in greenhouse. Measuring of thermal conductivity of soil

Energy Technology Data Exchange (ETDEWEB)

Iwao, Toshio; Takeyama, Koichi

1987-12-21

The underground heating system is an effective method of heating a greenhouse, because the system controls directly the temperature of soil near the roots. The thermal conductivity of soil was measured by the steady-state method, and the heat transfer characteristics in soil were examined in this study. In measuring the thermal conductivity through experiments, firstly the thermal conductivity of a reference plate was measured by the steady-state method, then on the basis of the above mentioned result, the thermal conuctivity of soil was obtained by the comparative method. Toyoura standard sands with particle size of 0.21-0.25mm were used as the sample. As the experiment result, the relations between the thermal conductivity of the reference plate (glass) and temperature was made clear, furthermore through the measurements using these relations, it was clarified that the apparent thermal conductivity is influenced by soil water content. It seems that the difference between the apparent thermal conductivity and the real one is caused mainly by a migration of latent heat with a migration of steam. (10 figs, 7 refs)

Precipitation and soil impacts on partitioning of subsurface moisture in Avena barbata: Observations from a greenhouse experiment

Energy Technology Data Exchange (ETDEWEB)

Salve, R.; Torn, M.S.

2011-03-01

The primary objective of this study was to assess the impact of two grassland soils and precipitation regimes on soil-moisture dynamics. We set up an experiment in a greenhouse, and monitored soil moisture dynamics in mesocosms planted with Avena barbata, an annual species found in California grasslands. By repeating the precipitation input at regular intervals, we were able to observe plant manipulation of soil moisture during well-defined periods during the growing season. We found that the amount of water partitioned to evapotranspiration, seepage, and soil storage varied among different growth stages. Further, both soil type and precipitation regimes had a significant impact on redistributing soil moisture. Whereas in the low-precipitation treatments most water was released to the atmosphere as evapotranspiration, major losses from the high-precipitation treatment occurred as gravity drainage. Observations from this study emphasize the importance of understanding intra-seasonal relationships between vegetation, soil, and water.

No tillage and liming reduce greenhouse gas emissions from poorly drained agricultural soils in Mediterranean regions

International Nuclear Information System (INIS)

García-Marco, Sonia; Abalos, Diego; Espejo, Rafael; Vallejo, Antonio; Mariscal-Sancho, Ignacio

2016-01-01

No tillage (NT) has been associated to increased N_2O emission from poorly drained agricultural soils. This is the case for soils with a low permeable Bt horizon, which generates a perched water layer after water addition (via rainfall or irrigation) over a long period of time. Moreover, these soils often have problems of acidity and require liming application to sustain crop productivity; changes in soil pH have large implications for the production and consumption of soil greenhouse gas (GHG) emissions. Here, we assessed in a split-plot design the individual and interactive effects of tillage practices (conventional tillage (CT) vs. NT) and liming (Ca-amendment vs. not-amendment) on N_2O and CH_4 emissions from poorly drained acidic soils, over a field experiment with a rainfed triticale crop. Soil mineral N concentrations, pH, temperature, moisture, water soluble organic carbon, GHG fluxes and denitrification capacity were measured during the experiment. Tillage increased N_2O emissions by 68% compared to NT and generally led to higher CH_4 emissions; both effects were due to the higher soil moisture content under CT plots. Under CT, liming reduced N_2O emissions by 61% whereas no effect was observed under NT. Under both CT and NT, CH_4 oxidation was enhanced after liming application due to decreased Al"3"+ toxicity. Based on our results, NT should be promoted as a means to improve soil physical properties and concurrently reduce N_2O and CH_4 emissions. Raising the soil pH via liming has positive effects on crop yield; here we show that it may also serve to mitigate CH_4 emissions and, under CT, abate N_2O emissions. - Highlights: • The effect of tillage and liming on GHG was studied in poorly drained acidic soils. • NT reduced N_2O emissions, global warming potential and greenhouse gases intensity. • Liming reduced N_2O and CH_4 emissions under CT; no effect was observed under NT. • NT and liming provide an opportunity for N_2O and CH_4 mitigation.

No tillage and liming reduce greenhouse gas emissions from poorly drained agricultural soils in Mediterranean regions

Energy Technology Data Exchange (ETDEWEB)

García-Marco, Sonia, E-mail: sonia.garcia@upm.es [Departamento de Química y Tecnología de los Alimentos, E.T.S.I. Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, Ciudad Universitaria, 28040 Madrid (Spain); Abalos, Diego, E-mail: diego.abalosrodriguez@wur.nl [Departamento de Química y Tecnología de los Alimentos, E.T.S.I. Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, Ciudad Universitaria, 28040 Madrid (Spain); Espejo, Rafael, E-mail: rafael.espejo@upm.es [Departamento de Producción Agraria, E.T.S.I. Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, Ciudad Universitaria, 28040 Madrid (Spain); Vallejo, Antonio, E-mail: antonio.vallejo@upm.es [Departamento de Química y Tecnología de los Alimentos, E.T.S.I. Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, Ciudad Universitaria, 28040 Madrid (Spain); Mariscal-Sancho, Ignacio, E-mail: i.mariscal@upm.es [Departamento de Producción Agraria, E.T.S.I. Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, Ciudad Universitaria, 28040 Madrid (Spain)

2016-10-01

No tillage (NT) has been associated to increased N{sub 2}O emission from poorly drained agricultural soils. This is the case for soils with a low permeable Bt horizon, which generates a perched water layer after water addition (via rainfall or irrigation) over a long period of time. Moreover, these soils often have problems of acidity and require liming application to sustain crop productivity; changes in soil pH have large implications for the production and consumption of soil greenhouse gas (GHG) emissions. Here, we assessed in a split-plot design the individual and interactive effects of tillage practices (conventional tillage (CT) vs. NT) and liming (Ca-amendment vs. not-amendment) on N{sub 2}O and CH{sub 4} emissions from poorly drained acidic soils, over a field experiment with a rainfed triticale crop. Soil mineral N concentrations, pH, temperature, moisture, water soluble organic carbon, GHG fluxes and denitrification capacity were measured during the experiment. Tillage increased N{sub 2}O emissions by 68% compared to NT and generally led to higher CH{sub 4} emissions; both effects were due to the higher soil moisture content under CT plots. Under CT, liming reduced N{sub 2}O emissions by 61% whereas no effect was observed under NT. Under both CT and NT, CH{sub 4} oxidation was enhanced after liming application due to decreased Al{sup 3+} toxicity. Based on our results, NT should be promoted as a means to improve soil physical properties and concurrently reduce N{sub 2}O and CH{sub 4} emissions. Raising the soil pH via liming has positive effects on crop yield; here we show that it may also serve to mitigate CH{sub 4} emissions and, under CT, abate N{sub 2}O emissions. - Highlights: • The effect of tillage and liming on GHG was studied in poorly drained acidic soils. • NT reduced N{sub 2}O emissions, global warming potential and greenhouse gases intensity. • Liming reduced N{sub 2}O and CH{sub 4} emissions under CT; no effect was observed under NT

Benefits of biochar, compost and biochar–compost for soil quality, maize yield and greenhouse gas emissions in a tropical agricultural soil

International Nuclear Information System (INIS)

Agegnehu, Getachew; Bass, Adrian M.; Nelson, Paul N.; Bird, Michael I.

2016-01-01

Soil quality decline represents a significant constraint on the productivity and sustainability of agriculture in the tropics. In this study, the influence of biochar, compost and mixtures of the two on soil fertility, maize yield and greenhouse gas (GHG) emissions was investigated in a tropical Ferralsol. The treatments were: 1) control with business as usual fertilizer (F); 2) 10 t ha"−"1 biochar (B) + F; 3) 25 t ha"−"1 compost (Com) + F; 4) 2.5 t ha"−"1 B + 25 t ha"−"1 Com mixed on site + F; and 5) 25 t ha"−"1 co-composted biochar–compost (COMBI) + F. Total aboveground biomass and maize yield were significantly improved relative to the control for all organic amendments, with increases in grain yield between 10 and 29%. Some plant parameters such as leaf chlorophyll were significantly increased by the organic treatments. Significant differences were observed among treatments for the δ"1"5N and δ"1"3C contents of kernels. Soil physicochemical properties including soil water content (SWC), total soil organic carbon (SOC), total nitrogen (N), available phosphorus (P), nitrate-nitrogen (NO_3"− N), ammonium-nitrogen (NH_4"+-N), exchangeable cations and cation exchange capacity (CEC) were significantly increased by the organic amendments. Maize grain yield was correlated positively with total biomass, leaf chlorophyll, foliar N and P content, SOC and SWC. Emissions of CO_2 and N_2O were higher from the organic-amended soils than from the fertilizer-only control. However, N_2O emissions generally decreased over time for all treatments and emission from the biochar was lower compared to other treatments. Our study concludes that the biochar and biochar–compost-based soil management approaches can improve SOC, soil nutrient status and SWC, and maize yield and may help mitigate greenhouse gas emissions in certain systems. - Graphical abstract: Grain yield, cation exchange capacity (CEC), soil organic carbon (SOC), soil water content (SWC) and N_2O

Benefits of biochar, compost and biochar–compost for soil quality, maize yield and greenhouse gas emissions in a tropical agricultural soil

Energy Technology Data Exchange (ETDEWEB)

Agegnehu, Getachew [College of Science, Technology and Engineering, Centre for Tropical Environmental and Sustainability Science, James Cook University, PO Box 6811, Cairns, Queensland 4870 (Australia); Bass, Adrian M. [Hawkesbury Institute for the Environment, University of Western Sydney, Science Road, Richmond, New South Wales 2753 (Australia); Nelson, Paul N.; Bird, Michael I. [College of Science, Technology and Engineering, Centre for Tropical Environmental and Sustainability Science, James Cook University, PO Box 6811, Cairns, Queensland 4870 (Australia)

2016-02-01

Soil quality decline represents a significant constraint on the productivity and sustainability of agriculture in the tropics. In this study, the influence of biochar, compost and mixtures of the two on soil fertility, maize yield and greenhouse gas (GHG) emissions was investigated in a tropical Ferralsol. The treatments were: 1) control with business as usual fertilizer (F); 2) 10 t ha{sup −1} biochar (B) + F; 3) 25 t ha{sup −1} compost (Com) + F; 4) 2.5 t ha{sup −1} B + 25 t ha{sup −1} Com mixed on site + F; and 5) 25 t ha{sup −1} co-composted biochar–compost (COMBI) + F. Total aboveground biomass and maize yield were significantly improved relative to the control for all organic amendments, with increases in grain yield between 10 and 29%. Some plant parameters such as leaf chlorophyll were significantly increased by the organic treatments. Significant differences were observed among treatments for the δ{sup 15}N and δ{sup 13}C contents of kernels. Soil physicochemical properties including soil water content (SWC), total soil organic carbon (SOC), total nitrogen (N), available phosphorus (P), nitrate-nitrogen (NO{sub 3}{sup −} N), ammonium-nitrogen (NH{sub 4}{sup +}-N), exchangeable cations and cation exchange capacity (CEC) were significantly increased by the organic amendments. Maize grain yield was correlated positively with total biomass, leaf chlorophyll, foliar N and P content, SOC and SWC. Emissions of CO{sub 2} and N{sub 2}O were higher from the organic-amended soils than from the fertilizer-only control. However, N{sub 2}O emissions generally decreased over time for all treatments and emission from the biochar was lower compared to other treatments. Our study concludes that the biochar and biochar–compost-based soil management approaches can improve SOC, soil nutrient status and SWC, and maize yield and may help mitigate greenhouse gas emissions in certain systems. - Graphical abstract: Grain yield, cation exchange capacity (CEC), soil

Spatiotemporal dynamics of phosphorus release, oxygen consumption and greenhouse gas emissions after localised soil amendment with organic fertilisers

DEFF Research Database (Denmark)

Christel, Wibke; Zhu, Kun; Hoefer, Christoph

2016-01-01

processes and fixation in the residue sphere, giving rise to distinct differences in nutrient availability, soil oxygen content and greenhouse gas (GHG) production. In this study we investigated the spatiotemporal dynamics of the reaction of manure solids and manure solids char with soil, focusing...... on their phosphorus (P) availability, as current emphasis on improving societal P efficiency through recycling waste or bio-based fertilisers necessitates a sound understanding of their behaviour. Soil layers amended at a constant P application rate with either pig manure solids or char made from pig manure solids...

Greenhouse gas emissions and plant characteristics from soil cultivated with sunflower (Helianthus annuus L.) and amended with organic or inorganic fertilizers

International Nuclear Information System (INIS)

López-Valdez, F.; Fernández-Luqueño, F.; Luna-Suárez, S.; Dendooven, L.

2011-01-01

Agricultural application of wastewater sludge has become the most widespread method of disposal, but the environmental effects on soil, air, and crops must be considered. The effect of wastewater sludge or urea on sunflower's (Helianthus annuus L.) growth and yield, the soil properties, and the resulting CO 2 and N 2 O emissions are still unknown. The objectives of this study were to investigate: i) the effect on soil properties of organic or inorganic fertilizer added to agricultural soil cultivated with sunflower, ii) how urea or wastewater sludge increases CO 2 and N 2 O emissions from agricultural soil over short time periods, and iii) the effect on plant characteristics and yield of urea or wastewater sludge added to agricultural soil cultivated with sunflower. The sunflower was fertilized with wastewater sludge or urea or grown in unamended soil under greenhouse conditions while plant and soil characteristics, yield, and greenhouse gas emissions were monitored. Sludge and urea modified some soil characteristics at the onset of the experiment and during the first two months but not thereafter. Some plant characteristics were improved by sludge. Urea and sludge treatments increased the yield at similar rates, while sludge-amended soil significantly increased N 2 O emissions but not CO 2 emissions compared to the other amended or unamended soils. This implies that wastewater sludge increased the biomass and/or the yield; however, from a holistic point of view, using wastewater sludge as fertilizer should be viewed with concern.

[Effect of Biochar on Soil Greenhouse Gas Emissions in Semi-arid Region].

Science.gov (United States)

Guo, Yan-liang; Wang, Dan-dan; Zheng, Ji-yong; Zhao, Shi-wei; Zhang, Xing-chang

2015-09-01

This study aimed to investigate the effects of biochar addition on the emission of greenhouse gases from farmland soil in semi-arid region. Through an in-situ experiments, the influence of sawdust biochar(J) and locust tree skin biochar (H) at three doses (1%, 3%, and 5% of quality percentage) on C2, CH4 and N2O emissions were studied within the six months in the south of Ningxiaprovince. The results indicated that soil CO2 emission flux was slightly increased with the addition doses for both biochars, and the averaged CO2 emission flux for sawdust and locust tree skin biochar was enhanced by 1. 89% and 3. 34% compared to the control, but the difference between treatments was not statistically significant. The soil CH4 emission was decreased with the increasing of biochar doses, by 1. 17%, 2. 55%, 4. 32% for J1, J3, J5 and 2. 35%, 5. 83%, 7. 32% for H1, H3, H5, respectively. However, the difference was statistically significant only for J5, H3 and H5 treatments (P effect on soil N2O emission. Our study indicated that the biochar has no significant influence on soil CO2 and N2O emissions within six months in semi-arid region and can significantly influence soil CH4 emissions (P < 0. 05). As for biochar type, the locust tree skin biochar is significantly better than the sawdust biochar in terms of restraining CH4 emission(P = 0. 048).

Greenhouse gas emissions and plant characteristics from soil cultivated with sunflower (Helianthus annuus L.) and amended with organic or inorganic fertilizers

Energy Technology Data Exchange (ETDEWEB)

Lopez-Valdez, F., E-mail: flopez2072@yahoo.com [Laboratory of Agricultural Biotechnology, CIBA, IPN, Tepetitla de Lardizabal, C.P. 90700, Tlaxcala (Mexico); Laboratory of Soil Ecology, GIB, Department of Biotechnology and Bioengineering, Cinvestav-Zacatenco, C.P. 07360, D.F. (Mexico); Fernandez-Luqueno, F. [Natural and Energetic Resources, Cinvestav-Saltillo, C.P. 25900, Coahuila (Mexico); Laboratory of Soil Ecology, GIB, Department of Biotechnology and Bioengineering, Cinvestav-Zacatenco, C.P. 07360, D.F. (Mexico); Luna-Suarez, S. [Laboratory of Agricultural Biotechnology, CIBA, IPN, Tepetitla de Lardizabal, C.P. 90700, Tlaxcala (Mexico); Dendooven, L. [Laboratory of Soil Ecology, GIB, Department of Biotechnology and Bioengineering, Cinvestav-Zacatenco, C.P. 07360, D.F. (Mexico)

2011-12-15

Agricultural application of wastewater sludge has become the most widespread method of disposal, but the environmental effects on soil, air, and crops must be considered. The effect of wastewater sludge or urea on sunflower's (Helianthus annuus L.) growth and yield, the soil properties, and the resulting CO{sub 2} and N{sub 2}O emissions are still unknown. The objectives of this study were to investigate: i) the effect on soil properties of organic or inorganic fertilizer added to agricultural soil cultivated with sunflower, ii) how urea or wastewater sludge increases CO{sub 2} and N{sub 2}O emissions from agricultural soil over short time periods, and iii) the effect on plant characteristics and yield of urea or wastewater sludge added to agricultural soil cultivated with sunflower. The sunflower was fertilized with wastewater sludge or urea or grown in unamended soil under greenhouse conditions while plant and soil characteristics, yield, and greenhouse gas emissions were monitored. Sludge and urea modified some soil characteristics at the onset of the experiment and during the first two months but not thereafter. Some plant characteristics were improved by sludge. Urea and sludge treatments increased the yield at similar rates, while sludge-amended soil significantly increased N{sub 2}O emissions but not CO{sub 2} emissions compared to the other amended or unamended soils. This implies that wastewater sludge increased the biomass and/or the yield; however, from a holistic point of view, using wastewater sludge as fertilizer should be viewed with concern.

Greenhouse gas emissions and plant characteristics from soil cultivated with sunflower (Helianthus annuus L.) and amended with organic or inorganic fertilizers.

Science.gov (United States)

López-Valdez, F; Fernández-Luqueño, F; Luna-Suárez, S; Dendooven, L

2011-12-15

Agricultural application of wastewater sludge has become the most widespread method of disposal, but the environmental effects on soil, air, and crops must be considered. The effect of wastewater sludge or urea on sunflower's (Helianthus annuus L.) growth and yield, the soil properties, and the resulting CO(2) and N(2)O emissions are still unknown. The objectives of this study were to investigate: i) the effect on soil properties of organic or inorganic fertilizer added to agricultural soil cultivated with sunflower, ii) how urea or wastewater sludge increases CO(2) and N(2)O emissions from agricultural soil over short time periods, and iii) the effect on plant characteristics and yield of urea or wastewater sludge added to agricultural soil cultivated with sunflower. The sunflower was fertilized with wastewater sludge or urea or grown in unamended soil under greenhouse conditions while plant and soil characteristics, yield, and greenhouse gas emissions were monitored. Sludge and urea modified some soil characteristics at the onset of the experiment and during the first two months but not thereafter. Some plant characteristics were improved by sludge. Urea and sludge treatments increased the yield at similar rates, while sludge-amended soil significantly increased N(2)O emissions but not CO(2) emissions compared to the other amended or unamended soils. This implies that wastewater sludge increased the biomass and/or the yield; however, from a holistic point of view, using wastewater sludge as fertilizer should be viewed with concern. Copyright © 2011 Elsevier B.V. All rights reserved.

Rich soil carbon and nitrogen but low atmospheric greenhouse gas fluxes from North Sulawesi mangrove swamps in Indonesia.

Science.gov (United States)

Chen, Guang C; Ulumuddin, Yaya I; Pramudji, Sastro; Chen, Shun Y; Chen, Bin; Ye, Yong; Ou, Dan Y; Ma, Zhi Y; Huang, Hao; Wang, Jing K

2014-07-15

The soil to atmosphere fluxes of greenhouse gases N2O, CH4 and CO2 and their relationships with soil characteristics were investigated in three tropical oceanic mangrove swamps (Teremaal, Likupang and Kema) in North Sulawesi, Indonesia. Mangrove soils in North Sulawesi were rich in organic carbon and nitrogen, but the greenhouse gas fluxes were low in these mangroves. The fluxes ranged -6.05-13.14 μmol m(-2)h(-1), -0.35-0.61 μmol m(-2)h(-1) and -1.34-3.88 mmol m(-2)h(-1) for N2O, CH4 and CO2, respectively. The differences in both N2O and CH4 fluxes among different mangrove swamps and among tidal positions in each mangrove swamp were insignificant. CO2 flux was influenced only by mangrove swamps and the value was higher in Kema mangrove. None of the measured soil parameters could explain the variation of CH4 fluxes among the sampling plots. N2O flux was negatively related to porewater salinity, while CO2 flux was negatively correlated with water content and organic carbon. This study suggested that the low gas emissions due to slow metabolisms would lead to the accumulations of organic matters in North Sulawesi mangrove swamps. Copyright © 2014 Elsevier B.V. All rights reserved.

Greenhouse intelligent control system based on microcontroller

Science.gov (United States)

Zhang, Congwei

2018-04-01

As one of the hallmarks of agricultural modernization, intelligent greenhouse has the advantages of high yield, excellent quality, no pollution and continuous planting. Taking AT89S52 microcontroller as the main controller, the greenhouse intelligent control system uses soil moisture sensor, temperature and humidity sensors, light intensity sensor and CO2 concentration sensor to collect measurements and display them on the 12864 LCD screen real-time. Meantime, climate parameter values can be manually set online. The collected measured values are compared with the set standard values, and then the lighting, ventilation fans, warming lamps, water pumps and other facilities automatically start to adjust the climate such as light intensity, CO2 concentration, temperature, air humidity and soil moisture of the greenhouse parameter. So, the state of the environment in the greenhouse Stabilizes and the crop grows in a suitable environment.

Simulating soil greenhouse emissions from Swiss long-term cropping system trials

Science.gov (United States)

Necpalova, Magdalena; Lee, Juhwan; Skinner, Colin; Büchi, Lucie; Berner, Alfred; Mäder, Paul; Mayer, Jochen; Charles, Raphael; van der Heijden, Marcel; Wittwer, Raphael; Gattinger, Andreas; Six, Johan

2017-04-01

There is an urgent need to identify and evaluate management practices for their bio-physical potential to mitigate greenhouse gas (GHG) emissions from agriculture. The cost and time required for direct management-specific GHG measurements limit the spatial and temporal resolution and the extent of data that can be collected. Biogeochemical process-based models such as DayCent can be used to bridge data gaps over space and time and estimate soil GHG emissions relevant to various climate change mitigation strategies. Objectives of this study were (a) to parameterize DayCent for common Swiss crops and crop-specific management practices using the Swiss long-term experimental data collected at four sites (Therwil, Frick, Changins, and Reckenholz); (b) to evaluate the model's ability to predict crop productivity, long-term soil carbon dynamics and N2O emissions from Swiss cropping systems; (c) to calculate a net soil GHG balance for all treatments (except for bio-dynamic) studied in long-term field experiments in Switzerland; and (d) to study the management effects and their interactions on soil GHG emissions at each experimental site. Model evaluation indicated that DayCent predicted crop productivity (rRMSE=0.29 r2=0.81, n=2614), change in soil carbon stock (rRMSE=0.14, r2=0.72, n=1289) and cumulative N2O emissions (rRMSE=0.25, r2=0.89, n=8) satisfactorily across all treatments and sites. Net soil GHG emissions were derived from changes in soil carbon, N2O emissions and CH4 oxidation on an annual basis using IPCC (2014) global warming potentials. Modelled net soil GHG emissions calculated for individual treatments over 30 years ranged from -594 to 1654 kg CO2 eq ha-1 yr-1. The highest net soil GHG emissions were predicted for conventional tillage and slurry application treatment at Frick, while soils under organic and reduced tillage management at Reckenholz acted as a net GHG sink. The statistical analyses using linear MIXED models indicated that net soil GHG

Carbon sequestration and greenhouse gases emissions in soil under sewage sludge residual effects

Directory of Open Access Journals (Sweden)

Leonardo Machado Pitombo

2015-02-01

Full Text Available The large volume of sewage sludge (SS generated with high carbon (C and nutrient content suggests that its agricultural use may represent an important alternative to soil carbon sequestration and provides a potential substitute for synthetic fertilizers. However, emissions of CH4 and N2O could neutralize benefits with increases in soil C or saving fertilizer production because these gases have a Global Warming Potential (GWP 25 and 298 times greater than CO2, respectively. Thus, this study aimed to determine C and N content as well as greenhouse gases (GHG fluxes from soils historically amended with SS. Sewage sludge was applied between 2001 and 2007, and maize (Zea mays L. was sowed in every year between 2001 and 2009. We evaluated three treatments: Control (mineral fertilizer, 1SS (recommended rate and 2SS (double rate. Carbon stocks (0-40 cm were 58.8, 72.5 and 83.1 Mg ha–1in the Control, 1SS and 2SS, respectively, whereas N stocks after two years without SS treatment were 4.8, 5.8, and 6.8 Mg ha–1, respectively. Soil CO2 flux was highly responsive to soil temperature in SS treatments, and soil water content greatly impacted gas flux in the Control. Soil N2O flux increased under the residual effects of SS, but in 1SS, the flux was similar to that found in moist tropical forests. Soil remained as a CH4sink. Large stores of carbon following historical SS application indicate that its use could be used as a method for carbon sequestration, even under tropical conditions.

Seasonal Variation in Soil Greenhouse Gas Emissions at Three Age-Stages of Dawn Redwood (Metasequoia glyptostroboides Stands in an Alluvial Island, Eastern China

Directory of Open Access Journals (Sweden)

Shan Yin

2016-11-01

Full Text Available Greenhouse gas (GHG emissions are an important part of the carbon (C and nitrogen (N cycle in forest soil. However, soil greenhouse gas emissions in dawn redwood (Metasequoia glyptostroboides stands of different ages are poorly understood. To elucidate the effect of plantation age and environmental factors on soil GHG emissions, we used static chamber/gas chromatography (GC system to measure soil GHG emissions in an alluvial island in eastern China for two consecutive years. The soil was a source of CO2 and N2O and a sink of CH4 with annual emissions of 5.5–7.1 Mg C ha−1 year−1, 0.15–0.36 kg N ha−1 year−1, and 1.7–4.5 kg C ha−1 year−1, respectively. A clear exponential correlation was found between soil temperature and CO2 emission, but a negative linear correlation was found between soil water content and CO2 emission. Soil temperature had a significantly positive effect on CH4 uptake and N2O emission, whereas no significant correlation was found between CH4 uptake and soil water content, and N2O emission and soil water content. These results implied that older forest stands might cause more GHG emissions from the soil into the atmosphere because of higher litter/root biomass and soil carbon/nitrogen content compared with younger stands.

Hysteresis of soil temperature under different soil moisture and ...

African Journals Online (AJOL)

... in a solar greenhouse. The objective of this study was to find a simple method to estimate the hysteresis of soil temperature under three soil moisture and two fertilizer levels in solar greenhouse conditions with tomato crop (Lycopersicon esculentum Mill). The results show that the soil moisture had no significant effects on ...

Soil pH management without lime, a strategy to reduce greenhouse gas emissions from cultivated soils

Science.gov (United States)

Nadeem, Shahid; Bakken, Lars; Reent Köster, Jan; Tore Mørkved, Pål; Simon, Nina; Dörsch, Peter

2015-04-01

For decades, agricultural scientists have searched for methods to reduce the climate forcing of food production by increasing carbon sequestration in the soil and reducing the emissions of nitrous oxide (N2O). The outcome of this research is depressingly meagre and the two targets appear incompatible: efforts to increase carbon sequestration appear to enhance the emissions of N2O. Currently there is a need to find alternative management strategies which may effectively reduce both the CO2 and N2O footprints of food production. Soil pH is a master variable in soil productivity and plays an important role in controlling the chemical and biological activity in soil. Recent investigations of the physiology of denitrification have provided compelling evidence that the emission of N2O declines with increasing pH within the range 5-7. Thus, by managing the soil pH at a near neutral level appears to be a feasible way to reduce N2O emissions. Such pH management has been a target in conventional agriculture for a long time, since a near-neutral pH is optimal for a majority of cultivated plants. The traditional way to counteract acidification of agricultural soils is to apply lime, which inevitably leads to emission of CO2. An alternative way to increase the soil pH is the use of mafic rock powders, which have been shown to counteract soil acidification, albeit with a slower reaction than lime. Here we report a newly established field trail in Norway, in which we compare the effects of lime and different mafic mineral and rock powders (olivine, different types of plagioclase) on CO2 and N2O emissions under natural agricultural conditions. Soil pH is measured on a monthly basis from all treatment plots. Greenhouse gas (GHG) emission measurements are carried out on a weekly basis using static chambers and an autonomous robot using fast box technique. Field results from the first winter (fallow) show immediate effect of lime on soil pH, and slower effects of the mafic rocks. The

Phytoremediation of contaminated soils containing gasoline using Ludwigia octovalvis (Jacq.) in greenhouse pots.

Science.gov (United States)

Al-Mansoory, Asia Fadhile; Idris, Mushrifah; Abdullah, Siti Rozaimah Sheikh; Anuar, Nurina

2017-05-01

Greenhouse experiments were carried out to determine the phytotoxic effects on the plant Ludwigia octovalvis in order to assess its applicability for phytoremediation gasoline-contaminated soils. Using plants to degrade hydrocarbons is a challenging task. In this study, different spiked concentrations of hydrocarbons in soil (1, 2, and 3 g/kg) were tested. The results showed that the mean efficiency of total petroleum hydrocarbon (TPH) removal over a 72-day culture period was rather high. The maximum removal of 79.8 % occurred for the 2 g/kg concentration, while the removal rate by the corresponding unplanted controls was only (48.6 %). The impact of gasoline on plants included visual symptoms of stress, yellowing, growth reduction, and perturbations in the developmental parameters. The dry weight and wet weight of the plant slightly increased upon exposure to gasoline until day 42. Scanning electron microscopy (SEM) indicated change to the root and stem structure in plant tissue due to the direct attachment with gasoline contaminated compared to the control sample. The population of living microorganisms in the contaminated soil was found to be able to adapt to different gasoline concentrations. The results showed that L. octovalvis and rhizobacteria in gasoline-contaminated soil have the potential to degrade organic pollutants.

Soil greenhouse gas emissions and carbon budgeting in a short-hydroperiod floodplain wetland

Science.gov (United States)

Batson, Jackie; Noe, Gregory B.; Hupp, Cliff R.; Krauss, Ken W.; Rybicki, Nancy B.; Schenk, Edward R.

2015-01-01

Understanding the controls on floodplain carbon (C) cycling is important for assessing greenhouse gas emissions and the potential for C sequestration in river-floodplain ecosystems. We hypothesized that greater hydrologic connectivity would increase C inputs to floodplains that would not only stimulate soil C gas emissions but also sequester more C in soils. In an urban Piedmont river (151 km2 watershed) with a floodplain that is dry most of the year, we quantified soil CO2, CH4, and N2O net emissions along gradients of floodplain hydrologic connectivity, identified controls on soil aerobic and anaerobic respiration, and developed a floodplain soil C budget. Sites were chosen along a longitudinal river gradient and across lateral floodplain geomorphic units (levee, backswamp, and toe slope). CO2 emissions decreased downstream in backswamps and toe slopes and were high on the levees. CH4 and N2O fluxes were near zero; however, CH4emissions were highest in the backswamp. Annual CO2 emissions correlated negatively with soil water-filled pore space and positively with variables related to drier, coarser soil. Conversely, annual CH4 emissions had the opposite pattern of CO2. Spatial variation in aerobic and anaerobic respiration was thus controlled by oxygen availability but was not related to C inputs from sedimentation or vegetation. The annual mean soil CO2 emission rate was 1091 g C m−2 yr−1, the net sedimentation rate was 111 g C m−2 yr−1, and the vegetation production rate was 240 g C m−2 yr−1, with a soil C balance (loss) of −338 g C m−2 yr−1. This floodplain is losing C likely due to long-term drying from watershed urbanization.

Greenhouse Gas Emissions and Growth of Wheat Cultivated in Soil Amended with Digestate from Biogas Production

Institute of Scientific and Technical Information of China (English)

Liliana PAMPILL(O)N-GONZ(A)LEZ; Marco LUNA-GUIDO; Olivia FRANCO-HERN(A)NDEZ; Fabián FERN(A)NDEZ-LUQUE(N)O; Octavio PAREDES-L(O)PEZ; Gerardo HERN(A)NDEZ; Luc DENDOOVEN

2017-01-01

Digestate,the product obtained after anaerobic digestion of organic waste for biogas production,is rich in plant nutrients and might be used to fertilize crops.Wheat (Triticum spp.L.) was fertilized with digestate,urea,or left unfertilized and cultivated in the greenhouse for 120 d.Emissions of greenhouse gasses (carbon dioxide (CO2),methane (CH4),and nitrous oxide (N2O)) were monitored and plant growth characteristics were determined at harvest.The digestate was characterized for heavy metals,pathogens,and C and N mineralization potential in an aerobic incubation experiment.No Salmonella spp.,Shigella spp.,or viable eggs of helminths were detected in the digested pig slurry,but the number of faecal coliforms was as high as 3.6 × 104 colony-forming units (CFU) g-1 dry digestate.The concentrations of heavy metals did not surpass the upper limits established by US Environmental Protection Agency (EPA).After 28 d,17％ of the organic C (436 g kg-1 dry digestate) and 8％ of the organic N (6.92 g kg-1 dry digestate) were mineralized.Emissions of CO2 and CH4 were not significantly affected by fertilization in the wheat-cultivated soil,but digestate significantly increased the cumulative N2O emission by 5 times compared to the urea-amended soil and 63 times compared to the uncultivated unfertilized soil.It could be concluded that digestate was nutrient rich and low in heavy metals and pathogens,and did not affect emissions of CH4 and CO2 when applied to a soil cultivated with wheat,but increased emission of N2O.

Effects of nitrogen fertilizer application on greenhouse gas emissions and economics of corn production.

Science.gov (United States)

Kim, Seungdo; Dale, Bruce E

2008-08-15

Nitrogen fertilizer plays an important role in corn cultivation in terms of both economic and environmental aspects. Nitrogen fertilizer positively affects corn yield and the soil organic carbon level, but it also has negative environmental effects through nitrogen-related emissions from soil (e.g., N20, NOx, NO3(-) leaching, etc.). Effects of nitrogen fertilizer on greenhouse gas emissions associated with corn grain are investigated via life cycle assessment. Ecoefficiency analysis is also used to determine an economically and environmentally optimal nitrogen application rate (NAR). The ecoefficiency index in this study is defined as the ratio of economic return due to nitrogen fertilizer to the greenhouse gas emissions of corn cultivation. Greenhouse gas emissions associated with corn grain decrease as NAR increases at a lower NAR until a minimum greenhouse gas emission level is reached because corn yield and soil organic carbon level increase with NAR. Further increasing NAR after a minimum greenhouse gas emission level raises greenhouse gas emissions associated with corn grain. Increased greenhouse gas emissions of corn grain due to nitrous oxide emissions from soil are much higher than reductions of greenhouse gas emissions of corn grain due to corn yield and changes in soil organic carbon levels at a higher NAR. Thus, there exists an environmentally optimal NAR in terms of greenhouse gas emissions. The trends of the ecoefficiency index are similar to those of economic return to nitrogen and greenhouse gas emissions associated with corn grain. Therefore, an appropriate NAR could enhance profitability as well as reduce greenhouse gas emissions associated with corn grain.

Phytoremediation of petroleum contaminated soils by Mirabilis Jalapa L. in a greenhouse plot experiment.

Science.gov (United States)

Peng, Shengwei; Zhou, Qixing; Cai, Zhang; Zhang, Zhineng

2009-09-15

Phytoremediation of soils contaminated by organic chemicals is a challenging problem in environmental science and engineering. On the basis of identifying remediation plants from ornamentals, the remediation capability of Mirabilis Jalapa L. to treat petroleum contaminated soil from the Shengli Oil Field in Dongying City, Shandong Province, China was further investigated using a field plot experiment carried out in a greenhouse. The results showed that the average efficiency of removing total petroleum hydrocarbons (TPHs) by M. jalapa over the 127-day culture period was high, up to 41.61-63.20%, when the removal rate by natural attenuation was only 19.75-37.92%. The maximum reduction occurred in the saturated hydrocarbon fraction compared with other components of petroleum contaminants. According to the qualitative and quantitative parameters including plant height, fresh weight, dry weight, root length, root weight and visual stress symptoms, it was indicated that M. jalapa had a peculiar tolerance to petroleum contamination and could effectively promote the degradation of TPHs when the concentration of petroleum hydrocarbons in soil was equal to and lower than 10,000 mg/kg. The population of living microorganisms in the planted soil could be also adaptive to contaminated soil. On the whole, M. jalapa is a widely spread species that can be effectively applied to phytoremediation of contaminated soil.

The Effect of Rubber Effluent on some Chemical Properties of Soil ...

African Journals Online (AJOL)

A preliminary pot trial was conducted in a greenhouse to determine the effects of rubber effluent on some soil chemical properties as well as early growth and nutrient uptake by maize plant. The levels of rubber effluent used were 0, 50, 100, 150, 200, 250 ml per 2 kg soil. The trial was arranged in a completely randomized ...

Effects of water-saving irrigation on emissions of greenhouse gases and prokaryotic communities in rice paddy soil.

Science.gov (United States)

Ahn, Jae-Hyung; Choi, Min-Young; Kim, Byung-Yong; Lee, Jong-Sik; Song, Jaekyeong; Kim, Gun-Yeob; Weon, Hang-Yeon

2014-08-01

The effects of water-saving irrigation on emissions of greenhouse gases and soil prokaryotic communities were investigated in an experimental rice field. The water layer was kept at 1-2 cm in the water-saving (WS) irrigation treatment and at 6 cm in the continuous flooding (CF) irrigation treatment. WS irrigation decreased CH(4) emissions by 78 % and increased N(2)O emissions by 533 %, resulting in 78 % reduction of global warming potential compared to the CF irrigation. WS irrigation did not affect the abundance or phylogenetic distribution of bacterial/archaeal 16S rRNA genes and the abundance of bacterial/archaeal 16S rRNAs. The transcript abundance of CH(4) emission-related genes generally followed CH(4) emission patterns, but the difference in abundance between mcrA transcripts and amoA/pmoA transcripts best described the differences in CH(4) emissions between the two irrigation practices. WS irrigation increased the relative abundance of 16S rRNAs and functional gene transcripts associated with Anaeromyxobacter and Methylocystis spp., suggesting that their activities might be important in emissions of the greenhouse gases. The N(2)O emission patterns were not reflected in the abundance of N(2)O emission-related genes and transcripts. We showed that the alternative irrigation practice was effective for mitigating greenhouse gas emissions from rice fields and that it did not affect the overall size and structure of the soil prokaryotic community but did affect the activity of some groups.

Greenhouse Warming Research

DEFF Research Database (Denmark)

Sørensen, Bent Erik

2016-01-01

The changing greenhouse effect caused by natural and anthropogenic causes is explained and efforts to model the behavior of the near-surface constituents of the Earth's land, ocean and atmosphere are discussed. Emissions of various substances and other aspects of human activity influence...... the greenhouse warming, and the impacts of the warming may again impact the wellbeing of human societies. Thus physical modeling of the near-surface ocean-soil-atmosphere system cannot be carried out without an idea of the development of human activities, which is done by scenario analysis. The interactive...

Net soil respiration and greenhouse gas balance along a sequence of forest disturbance to smallholder rubber and oil palm plantations in Sumatra

Science.gov (United States)

Khusyu Aini, Fitri; Hergoualc'h, Kristell; Smith, Jo; Verchot, Louis; Martius, Christopher

2017-04-01

The rapid increase in demand for land to establish oil palm and rubber plantations has led to the conversion of forests, with potential impacts on greenhouse gas emissions and on climate change. This study evaluates the net greenhouse gas balance following forest change to other land uses, i.e. one year rubber plantation, twenty-year rubber plantation and eight year oil palm plantation on Sumatran mineral soils. None of the plantations had ever been fertilized previously. During this study they were fertilized to provide nitrogen at the recommended rate used by farmers (33.3 kg N ha-1 y-1). The ecosystem stores carbon in litterfall, standing litter biomass (undergrowth vegetation, leaves, twigs, litter on the soil surface), soil organic matter, root biomass, and standing tree biomass. It releases carbon to the atmosphere through soil respiration fluxes, negative values indicating that carbon is stored by the land use change and positive values indicating emissions to the atmosphere. Net soil respiration was assessed using a mass balance approach: standing litter and tree biomass were measured once; the rate of carbon accumulation from standing litter and tree biomass was calculated by dividing the stock by the age of plantation or the time since logging started in the disturbed forest. The carbon accumulation in standing litter, tree biomass in the forest and soil organic matter for all land-uses was estimated from available in the literature. Root biomass for each land-use system was calculated using the root:shoot ratio. The net soil respiration of carbon dioxide from the forest, disturbed forest, one year rubber plantation, twenty-year rubber plantation and oil palm plantation were calculated to be -6 (± 5), 12 (± 6), 11 (± 15), 10 (± 5), 39 (± 7) Mg ha-1 y-1, respectively. Soil nitrous oxide, methane and litterfall were measured for 14 months and respiration fluxes were measured for 5 months across land uses and different seasons. The measured emissions of

Improvement of red pepper yield and soil environment by summer catch aquatic crops in greenhouses

Science.gov (United States)

Du, X. F.; Wang, L. Z.; Peng, J.; Wang, G. L.; Guo, X. S.; Wen, T. G.; Gu, D. L.; Wang, W. Z.; Wu, C. W.

2016-08-01

To investigate effects of the rotation of summer catch crops on remediation retrogressed soils in continuous cropping, a field experiment was conducted. Rice, water spinach, or cress were selected as summer catch crops; bare fallow during summer fallow was used as the control group. Results showed that aquatic crops grown in summer fallow period could effectively reduce soil bulk density and pH, facilitate soil nutrient release, and improve soil physical and chemical properties compared with those grown in fallow period. Paddy-upland rotation could improve soil microbial members and increase bacterial and actinomycete populations; by contrast, paddy-upland rotation could reduce fungal populations and enhance bacterium-to-fungus ratio. Paddy-upland rotation could also actively promote activities of soil enzymes, such as urease, phosphatase, invertase, and catalase. The proposed paddy-upland rotation significantly affected the growth of red pepper; the yield and quality of the grown red pepper were enhanced. Summer catch crops, such as rice, water spinach, and cress significantly increased pepper yield in the following growing season by 15.4%, 10.2% and 14.0%, respectively, compared with those grown in fallow treatment. Therefore, the proposed paddy-upland crop rotation could be a useful method to alleviate continuous cropping problems involved in cultivating red pepper in greenhouses.

[Interactions of straw, nitrogen fertilizer and bacterivorous nematodes on soil labile carbon and nitrogen and greenhouse gas emissions].

Science.gov (United States)

Zhang, Teng-Hao; Wang, Nan; Liu, Man-Qiang; Li, Fang-Hui; Zhu, Kang-Li; Li, Hui-Xin; Hu, Feng

2014-11-01

A 3 x 2 factorial design of microcosm experiment was conducted to investigate the interactive effects of straw, nitrogen fertilizer and bacterivorous nematodes on soil microbial biomass carbon (C(mic)) and nitrogen (N(mic)), dissolved organic carbon (DOC) and nitrogen (DON), mineral nitrogen (NH(4+)-N and NO(3-)-N), and greenhouse gas (CO2, N2O and CH4) emissions. Results showed that straw amendment remarkably increased the numbers of bacterivorous nematodes and the contents of Cmic and Nmic, but Cmic and Nmic decreased with the increasing dose of nitrogen fertilization. The effects of bacterivorous nematodes strongly depended on either straw or nitrogen fertilization. The interactions of straw, nitrogen fertilization and bacterivorous nematodes on soil DOC, DON and mineral nitrogen were strong. Straw and nitrogen fertilization increased DOC and mineral nitrogen contents, but their influences on DON depended on the bacterivorous nematodes. The DOC and mineral nitrogen were negatively and positively influenced by the bacterivorous nematodes, re- spectively. Straw significantly promoted CO2 and N2O emissions but inhibited CH4 emission, while interactions between nematodes and nitrogen fertilization on emissions of greenhouse gases were obvious. In the presence of straw, nematodes increased cumulative CO2 emissions with low nitrogen fertilization, but decreased CO2 and N2O emissions with high nitrogen fertilization on the 56th day after incubation. In summary, mechanical understanding the soil ecological process would inevitably needs to consider the roles of soil microfauna.

On the determination of the overall heat transmission coefficient and soil heat flux for a fog cooled, naturally ventilated greenhouse: Analysis of radiation and convection heat transfer

International Nuclear Information System (INIS)

Abdel-Ghany, Ahmed M.; Kozai, Toyoki

2006-01-01

A physical model for analyzing the radiative and convective heat transfer in a fog cooled, naturally ventilated greenhouse was developed for estimating the overall heat transmission coefficient based on the conduction, convection and thermal radiation heat transfer coefficients and for predicting the soil heat flux. The contribution of the water vapor of the inside air to the emission and absorption of thermal radiation was determined. Measurements of the outside and inside greenhouse environments to be used in the analysis were conducted around solar noon (12:19-13:00) on a hot sunny day to provide the maximum solar radiation transmission into the greenhouse. The net solar radiation flux measured at the greenhouse floor showed a reasonable agreement with the predicted value. The net fluxes were estimated around noon. The average net radiation (solar and thermal) at the soil surface was 220.0 W m -2 , the average soil heat flux was 155.0 W m -2 and the average contribution of the water vapor of the inside air to the thermal radiation was 22.0 W m -2 . The average overall heat transmission coefficient was 4.0 W m -2 C -1 and was in the range between 3.0 W m -2 C -1 and 6.0 W m -2 C -1 under the different hot summer conditions between the inside and outside of the naturally ventilated, fog cooled greenhouse

Changes in soil carbon and enzyme activity as a result of different long-term fertilization regimes in a greenhouse field.

Directory of Open Access Journals (Sweden)

Lili Zhang

Full Text Available In order to discover the advantages and disadvantages of different fertilization regimes and identify the best management practice of fertilization in greenhouse fields, soil enzyme activities involved in carbon (C transformations, soil chemical characteristics, and crop yields were monitored after long-term (20-year fertilization regimes, including no fertilizer (CK, 300 kg N ha-1 and 600 kg N ha-1 as urea (N1 and N2, 75 Mg ha-1 horse manure compost (M, and M with either 300 or 600 kg N ha-1 urea (MN1 and MN2. Compared with CK, fertilization increased crop yields by 31% (N2 to 69% (MN1. However, compared with CK, inorganic fertilization (especially N2 also caused soil acidification and salinization. In the N2 treatment, soil total organic carbon (TOC decreased from 14.1±0.27 g kg-1 at the beginning of the long-term experiment in 1988 to 12.6±0.11 g kg-1 (P<0.05. Compared to CK, N1 and N2 exhibited higher soil α-galactosidase and β-galactosidase activities, but lower soil α-glucosidase and β-glucosidase activities (P<0.05, indicating that inorganic fertilization had different impacts on these C transformation enzymes. Compared with CK, the M, MN1 and MN2 treatments exhibited higher enzyme activities, soil TOC, total nitrogen, dissolved organic C, and microbial biomass C and N. The fertilization regime of the MN1 treatment was identified as optimal because it produced the highest yields and increased soil quality, ensuring sustainability. The results suggest that inorganic fertilizer alone, especially in high amounts, in greenhouse fields is detrimental to soil quality.

Emission Characteristics of Greenhouse Gas from Maize Field of Black Soil Region Under Long-term Fertilization

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GAO Hong-jun

2017-08-01

Full Text Available Study on greenhouse gases emission and their global warming potential under different fertilizations would be the theoretical basis for establishing measurements to reduce greenhouses gas emissions. Based on a long-term fertilization experiment, greenhouses gas(GHG emissions from black soil of summer maize were measured by using a static chamber-gas chromatograph technique, and global warming potential(GWP effect was also estimated. The results showed the peaks of CO2 and N2O emissions occurred at maize jointing period. The CO2 and N2O emission flux and CH4 uptake flux in the M2NPK treatment(mixed application of organic fertilizer and chemical fertilizer were significantly higher than those of the chemical fertilizer treatments(P2 and N2O emission flux in the chemical fertilizer treatments were higher than that of the no fertilizer treatment. The CO2 emission flux of the fallow treatment was the highest among all the treatments, but its N2O emission flux was significantly lower than that of the chemical fertilizer treatment. Under equal N rates, the N2O emission flux of the NPK treatment was significantly higher than that of the SNPK treatment(straw returning, but CH4 uptake flux was the opposite result. Compared with no fertilizer treatment(CK, GWP of the N and NPK treatments increased by 142% and 32% respectively, GWP of SNPK treatment decreased by 38%, and GWP in the M2NPK treatment was negative value. Greenhouse gas emission intensity(GHGI of the NPK, SNPK and M2NPK treatments were significantly lower than that of the CK and the N treatments, GHGI of the M2NPK treatment was -222 kg CO2-eq·t-1. Therefore, in order to implement the higher maize yield with lower GHGI synchronously, mixed application of organic fertilizer and chemical fertilizer would be the optimal fertilization measurement in black soil region of Northeast China.

Offsetting global warming-induced elevated greenhouse gas emissions from an arable soil by biochar application.

Science.gov (United States)

Bamminger, Chris; Poll, Christian; Marhan, Sven

2018-01-01

Global warming will likely enhance greenhouse gas (GHG) emissions from soils. Due to its slow decomposability, biochar is widely recognized as effective in long-term soil carbon (C) sequestration and in mitigation of soil GHG emissions. In a long-term soil warming experiment (+2.5 °C, since July 2008) we studied the effect of applying high-temperature Miscanthus biochar (0, 30 t/ha, since August 2013) on GHG emissions and their global warming potential (GWP) during 2 years in a temperate agroecosystem. Crop growth, physical and chemical soil properties, temperature sensitivity of soil respiration (R s ), and metabolic quotient (qCO 2 ) were investigated to yield further information about single effects of soil warming and biochar as well as on their interactions. Soil warming increased total CO 2 emissions by 28% over 2 years. The effect of warming on soil respiration did not level off as has often been observed in less intensively managed ecosystems. However, the temperature sensitivity of soil respiration was not affected by warming. Overall, biochar had no effect on most of the measured parameters, suggesting its high degradation stability and its low influence on microbial C cycling even under elevated soil temperatures. In contrast, biochar × warming interactions led to higher total N 2 O emissions, possibly due to accelerated N-cycling at elevated soil temperature and to biochar-induced changes in soil properties and environmental conditions. Methane uptake was not affected by soil warming or biochar. The incorporation of biochar-C into soil was estimated to offset warming-induced elevated GHG emissions for 25 years. Our results highlight the suitability of biochar for C sequestration in cultivated temperate agricultural soil under a future elevated temperature. However, the increased N 2 O emissions under warming limit the GHG mitigation potential of biochar. © 2017 John Wiley & Sons Ltd.

Economic analysis of irrigated melon cultivated in greenhouse with and without soil plastic mulching

Directory of Open Access Journals (Sweden)

Elvis M. de C. Lima

Full Text Available ABSTRACT The objective of this study was to analyze technically and economically the irrigated ‘Gália’ melon (Hybrid Nectar, cultivated in greenhouse with and without using plastic mulch covering on the soil. Simultaneously, two experiments were conducted using a completely randomized design (CRD, in which melon plants were submitted to five water availability levels, defined by 50, 75, 100, 125, and 150% of crop evapotranspiration, with four replicates. The difference between experiments were only about the soil covering with plastic mulch: with (CC or without (SC plastic mulch. The economically optimal irrigation depths were 208.83 and 186.88 mm, resulting in yields of 50.85 and 44.51 t ha-1 for the experiments with and without mulching, respectively. The results showing the economically optimal irrigation depths were very close to those that produced the highest yield.

Comparison of Rooting Strategies to Explore Rock Fractures for Shallow Soil-Adapted Tree Species with Contrasting Aboveground Growth Rates: A Greenhouse Microcosm Experiment.

Science.gov (United States)

Nie, Yunpeng; Chen, Hongsong; Ding, Yali; Yang, Jing; Wang, Kelin

2017-01-01

For tree species adapted to shallow soil environments, rooting strategies that efficiently explore rock fractures are important because soil water depletion occurs frequently. However, two questions: (a) to what extent shallow soil-adapted species rely on exploring rock fractures and (b) what outcomes result from drought stress, have rarely been tested. Therefore, based on the expectation that early development of roots into deep soil layers is at the cost of aboveground growth, seedlings of three tree species ( Cyclobalanopsis glauca, Delavaya toxocarpa , and Acer cinnamomifolium ) with distinct aboveground growth rates were selected from a typical shallow soil region. In a greenhouse experiment that mimics the basic features of shallow soil environments, 1-year-old seedlings were transplanted into simulated microcosms of shallow soil overlaying fractured bedrock. Root biomass allocation and leaf physiological activities, as well as leaf δ 13 C values were investigated and compared for two treatments: regular irrigation and repeated cycles of drought stress. Our results show that the three species differed in their rooting strategies in the context of encountering rock fractures, however, these strategies were not closely related to the aboveground growth rate. For the slowest-growing seedling, C. glauca , percentages of root mass in the fractures, as well as in the soil layer between soil and bedrock increased significantly under both treatments, indicating a specialized rooting strategy that facilitated the exploration of rock fractures. Early investment in deep root growth was likely critical to the establishment of this drought-vulnerable species. For the intermediate-growing, A. cinnamomifolium , percentages of root mass in the bedrock and interface soil layers were relatively low and exhibited no obvious change under either treatment. This limited need to explore rock fractures was compensated by a conservative water use strategy. For the fast-growing, D

Comparison of Rooting Strategies to Explore Rock Fractures for Shallow Soil-Adapted Tree Species with Contrasting Aboveground Growth Rates: A Greenhouse Microcosm Experiment

Directory of Open Access Journals (Sweden)

Yunpeng Nie

2017-09-01

Full Text Available For tree species adapted to shallow soil environments, rooting strategies that efficiently explore rock fractures are important because soil water depletion occurs frequently. However, two questions: (a to what extent shallow soil-adapted species rely on exploring rock fractures and (b what outcomes result from drought stress, have rarely been tested. Therefore, based on the expectation that early development of roots into deep soil layers is at the cost of aboveground growth, seedlings of three tree species (Cyclobalanopsis glauca, Delavaya toxocarpa, and Acer cinnamomifolium with distinct aboveground growth rates were selected from a typical shallow soil region. In a greenhouse experiment that mimics the basic features of shallow soil environments, 1-year-old seedlings were transplanted into simulated microcosms of shallow soil overlaying fractured bedrock. Root biomass allocation and leaf physiological activities, as well as leaf δ13C values were investigated and compared for two treatments: regular irrigation and repeated cycles of drought stress. Our results show that the three species differed in their rooting strategies in the context of encountering rock fractures, however, these strategies were not closely related to the aboveground growth rate. For the slowest-growing seedling, C. glauca, percentages of root mass in the fractures, as well as in the soil layer between soil and bedrock increased significantly under both treatments, indicating a specialized rooting strategy that facilitated the exploration of rock fractures. Early investment in deep root growth was likely critical to the establishment of this drought-vulnerable species. For the intermediate-growing, A. cinnamomifolium, percentages of root mass in the bedrock and interface soil layers were relatively low and exhibited no obvious change under either treatment. This limited need to explore rock fractures was compensated by a conservative water use strategy. For the fast

Soil-atmosphere greenhouse-gas exchange in a bioretention system

Science.gov (United States)

Daly, E.; Chan, H.; Beringer, J.; Livesley, S. J.

2011-12-01

Bioretention systems are a popular green-technology for the management of urban stormwater runoff in many countries. They typically consist of a trench filled with a highly permeable soil medium that supports vegetation; runoff is diverted to bioretention systems and, by percolating through the filter medium, is subjected to a number of treatment processes. Nitrogen (N) is one of the key pollutants targeted by bioretention systems, which are able to reduce N concentrations considerably from inflow to outflow. To increase N removal, a saturated zone at the bottom of the filter medium is often artificially generated, to both enhance the denitrification process and increase the water available to the vegetation between inflow events. Although studies on the N-removal performance of bioretention systems are widely available in the literature, less is known about the exchange of greenhouse gases (GHG), especially nitrous oxide (N2O), between the bioretention systems and the atmosphere. Here, we present an experimental pilot study to measure N2O and CO2 soil emissions in a bioretention system installed on the Clayton Campus of Monash University in Melbourne, Australia. The bioretention system is divided into three cells, each 15 m2; the system as a whole receives water run-off from 4500 m2 of impervious car park. We monitored two cells with mostly sandy-loam vegetated with native sedges (mainly Carex Appressa and Lomandra Longifolia), one with and one without a saturated zone. Three manual flux chambers were installed in both cells. Gas flux samples were taken twice a week at about 11 am between the 2nd of March and the 18th of May 2011 (late summer and fall). Since October 2010, air-phase soil CO2 concentration profiles were measured continuously using solid-state infrared CO2 transmitters (GMT-221 model, Vaisala, Finland), along with soil moisture and soil temperature. Preliminary analysis of the chamber data (March only) showed that N2O fluxes were in general below 50

Risk Assessment from Radon Gas in the Greenhouses

International Nuclear Information System (INIS)

Fahmi, N.M.; El-Khatib, A.M.; Abd El-Zaher, M

2009-01-01

Radon is a naturally occurring radioactive gas found in varying amounts in all soils. Therefore, it is very important to study radon emanation from different soils in different circumstances; especially, in green houses which widely used to propagate and cultivate of plants. In greenhouses radon comes from either soil or the substances which make suitable flooring in the greenhouse. Radon and its progeny are accumulated in the air and on the plants themselves, which causes hazard for workers and customers in a later stage. Radon gas is measured in two kinds of greenhouses, one of them is constructed from plastic sheet and the other from glass (Agriculture Research Center - Horticulture Research Institute) using CR-39 NTDs as a passive technique. It based on the production of track in the detector due to alpha-particles emitted from radon and its progeny. The observed track densities are then converted to annual radon dose to be 12.36 mSv and 8.3 mSv for the plastic and glass greenhouses under investigation, respectively. It is also found that the workers have been subject to regulatory control

Sistem Monitoring Suhu Dan Kelembaban Tanaman Cabai Pada Greenhouse Berbasis Labview

OpenAIRE

Syarief, Syafrizal; Neparassi, William Benelliwod; Nurwidiana, Gendis Anisa

2016-01-01

. This study discusses the Temperature and Humidity Monitoring System Chili Plant Greenhouse Based on LabVIEW. Each plant requires a climate in order to grow optimally and results in a good quality. Greenhouse is ideal for the cultivation of various crops, especially of pepper plants. In the greenhouse is used multiple sensors such as sensors DHT11 which serves as a detector temperature and humidity of the environment, soil moisture sensor as a detector of soil moisture and the addition of LD...

Soil Solution

NARCIS (Netherlands)

Sonneveld, C.; Voogt, W.

2009-01-01

The characteristics of the soil solution in the root environment in the greenhouse industry differ much from those for field grown crops. This is caused firstly by the growing conditions in the greenhouse, which strongly differ from those in the field and secondly the function attributed to the soil

Greenhouse Gas Emissions from Excavation on Residential Construction Sites

Directory of Open Access Journals (Sweden)

Perry Forsythe

2014-12-01

Full Text Available Despite considerable research concerning the manifestation of greenhouse gases in the usage of buildings, little has been done concerning emissions arising from the construction process itself. This paper specifically examines emissions arising from cut and fill excavation on residential construction sites. Even though such excavation is often seen as being economical in terms of providing a flat base for concrete raft slab construction, the environmental consequences of this approach need to be considered more fully in terms of impact on the environment. This is particularly important when steeply sloping sites are involved and for different soil types. The paper undertakes a study that quantitatively assesses the cumulative greenhouse gas emissions caused by cut and fill excavation on 52 residential projects in Australia for a range of slope and soil types. The paper presents results from the study and concludes that greenhouse gas emissions increase as site slope increases; the building footprint area (as distinct from Gross Floor Area, exposes the need to reduce the area of the building to reduce greenhouse gas emissions; excavation of rock soils creates higher emissions than other soil types; and cut and fill excavation on steeply slope sites increase emissions. Potential alternative construction includes suspended floor construction systems which involve less excavation.

Greenhouse Gas Emissions from Excavation on Residential Construction Sites

Directory of Open Access Journals (Sweden)

Perry Forsythe

2014-12-01

Full Text Available Despite considerable research concerning the manifestation of greenhouse gases in the usage of buildings, little has been done concerning emissions arising from the construction process itself. This paper specifically examines emissions arising from cut and fill excavation on residential construction sites. Even though such excavation is often seen as being economical in terms of providing a flat base for concrete raft slab construction, the environmental consequences of this approach need to be considered more fully in terms of impact on the environment. This is particularly important when steeply sloping sites are involved and for different soil types. The paper undertakes a study that quantitatively assesses the cumulative greenhouse gas emissions caused by cut and fill excavation on 52 residential projects in Australia for a range of slope and soil types. The paper presents results from the study and concludes that greenhouse gas emissions increase as site slope increases; the building footprint area (as distinct from Gross Floor Area, exposes the need to reduce the area of the building to reduce greenhouse gas emissions; excavation of rock soils creates higher emissions than other soil types; and cut and fill excavation on steeply slope sites increase emissions. Potential alternative construction includes suspended floor construction systems which involve less excavation. 

Role of organic amendment application on greenhouse gas emission from soil

Energy Technology Data Exchange (ETDEWEB)

Thangarajan, Ramya, E-mail: thary008@mymail.unisa.edu.au [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, Adelaide, SA 5095 (Australia); Bolan, Nanthi S. [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, Adelaide, SA 5095 (Australia); Tian, Guanglong [Environmental Monitoring and Research Division, Monitoring and Research Dep., Metropolitan Water Reclamation District of Greater Chicago, 6001, Pershing Road, Cicero, IL 60804 (United States); Naidu, Ravi [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, Adelaide, SA 5095 (Australia); Kunhikrishnan, Anitha [Chemical Safety Division, Department of Agro-Food Safety, National Academy of Agricultural Science,10 Suwon-si, Gyeonggi-do (Korea, Republic of)

2013-11-01

Globally, substantial quantities of organic amendments (OAs) such as plant residues (3.8 × 10{sup 9} Mg/yr), biosolids (10 × 10{sup 7} Mg/yr), and animal manures (7 × 10{sup 9} Mg/yr) are produced. Recycling these OAs in agriculture possesses several advantages such as improving plant growth, yield, soil carbon content, and microbial biomass and activity. Nevertheless, OA applications hold some disadvantages such as nutrient eutrophication and greenhouse gas (GHG) emission. Agriculture sector plays a vital role in GHG emission (carbon dioxide— CO{sub 2}, methane— CH{sub 4}, and nitrous oxide— N{sub 2}O). Though CH{sub 4} and N{sub 2}O are emitted in less quantity than CO{sub 2}, they are 21 and 310 times more powerful in global warming potential, respectively. Although there have been reviews on the role of mineral fertilizer application on GHG emission, there has been no comprehensive review on the effect of OA application on GHG emission in agricultural soils. The review starts with the quantification of various OAs used in agriculture that include manures, biosolids, and crop residues along with their role in improving soil health. Then, it discusses four major OA induced-GHG emission processes (i.e., priming effect, methanogenesis, nitrification, and denitrification) by highlighting the impact of OA application on GHG emission from soil. For example, globally 10 × 10{sup 7} Mg biosolids are produced annually which can result in the potential emission of 530 Gg of CH{sub 4} and 60 Gg of N{sub 2}O. The article then aims to highlight the soil, climatic, and OA factors affecting OA induced-GHG emission and the management practices to mitigate the emission. This review emphasizes the future research needs in relation to nitrogen and carbon dynamics in soil to broaden the use of OAs in agriculture to maintain soil health with minimum impact on GHG emission from agriculture. - Highlights: ► A comprehensive overview for the first time on GHG emission from

Evaluation of an earth heat storage system in a solar energy greenhouse

Energy Technology Data Exchange (ETDEWEB)

Zhang, Q.; Langrell, J.; Boris, R. [Manitoba Univ., Winnipeg, MB (Canada). Dept. of Biosystems Engineering

2010-07-01

Greenhouses store solar energy in the walls and floors during the daytime and release the stored energy back to the greenhouse at night. In this study, an earth heat storage system was constructed and tested in a solar energy greenhouse in order to enhance energy storage. The system consisted of a network of perforated pipes buried in the soil at depths from 0.3 to 1 m. The warm air near the greenhouse ceiling was drawn to the buried pipes. Soil and air temperatures were recorded at various locations by a network of thermocouples. The energy balance was analyzed in order to evaluate the effectiveness of the earth heat storage system. The temperature profiles in the soil were used to determine the summer recharge and winter energy depletion behaviour of the system.

Soil P forms and P uptake under intensive plant growth in the greenhouse

International Nuclear Information System (INIS)

Henriquez, Carlos; Killorn, Randy

2005-01-01

The concentration of available soil (P) is a function of the equilibrium established among different soil P forms through numerous and different reactions in soil. The objective of this study was to examine the changes in P forms and P supply under exhaustive extraction conditions in soils from 3 different land use areas. In order to establish a greenhouse experiment, representative soil samples (0-20 cm) were taken from three fields located adjacent to one another, in a Typic Hapludands in Costa Rica. One field was a coffee plantation (Coffea arabica var Catuai), the second a sugar cane plantation (Saccarum spp. var 611721), and the third a secondary forest. Sorghum bicolor var Glazer 41) was planted in 1-liter pots and harvested 4 times consecutively. Treatments were no P and P application (100 mg kg -1 ) for each of the different land-use soil samples. Shoot and root dry matter and total P uptake were determined. Soil samples were taken before and after each of the 4 plant growth cycles and analyzed using a modified Hedley et al. (1982) soil P fractionation methodology. Labile-Pi, NaOH-Pi, HCI-Pi, extractable-Po, and residual -P were determined. Applied P increased labile-Pi, NaOH-Pi and HCI-Pi. Statistical changes were not observed in extractable organic P and residual-P due to P application. The NaOH-Pi and HCI-Pi seemed to act as a temporary pool of applied P. The possible participation of residual-P in replenishment of labile-P and NaOH-Pi was observed. The amount of plant P untake was closely related to the initial amount of labile-Pi and was higher in coffee than in forest and sugar cane soils. The labile-P was depleted by plant uptake. Rapid changes in reversibly available soil P forms (NaOH-Pi and HCI-Pi) were observed during the experiment. Our results suggest the occurrence of very rapid and dynamic changes between available and unavailable soil P forms in response to fertilizer application and plant uptake, supporting the idea of a continuum among the

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

Science.gov (United States)

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

2017-03-01

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

Towards a model-based inventory of soil organic carbon in agricultural soils for the Swiss greenhouse gas reporting

Science.gov (United States)

Staudt, K.; Leifeld, J.; Bretscher, D.; Fuhrer, J.

2012-04-01

The Swiss inventory submission under the United Nations Framework Convention on Climate Change (UNFCCC) reports on changes in soil organic carbon stocks under different land-uses and land-use changes. The approach currently employed for cropland and grassland soils combines Tier 1 and Tier 2 methods and is considered overly simplistic. As the UNFCC encourages countries to develop Tier 3 methods for national greenhouse gas reporting, we aim to build up a model-based inventory of soil organic carbon in agricultural soils in Switzerland. We conducted a literature research on currently employed higher-tier methods using process-based models in four countries: Denmark, Sweden, Finland and the USA. The applied models stem from two major groups differing in complexity - those belonging to the group of general ecosystem models that include a plant-growth submodel, e.g. Century, and those that simulate soil organic matter turnover but not plant-growth, e.g. ICBM. For the latter group, carbon inputs to the soil from plant residues and roots have to be determined separately. We will present some aspects of the development of a model-based inventory of soil organic carbon in agricultural soils in Switzerland. Criteria for model evaluation are, among others, modeled land-use classes and land-use changes, spatial and temporal resolution, and coverage of relevant processes. For model parameterization and model evaluation at the field scale, data from several long-term agricultural experiments and monitoring sites in Switzerland is available. A subsequent regional application of a model requires the preparation of regional input data for the whole country - among others spatio-temporal meteorological data, agricultural and soil data. Following the evaluation of possible models and of available data, preference for application in the Swiss inventory will be given to simpler model structures, i.e. models without a plant-growth module. Thus, we compared different allometric relations

Human footprints on greenhouse gas fluxes in cryogenic ecosystems

Science.gov (United States)

Karelin, D. V.; Goryachkin, S. V.; Zamolodchikov, D. G.; Dolgikh, A. V.; Zazovskaya, E. P.; Shishkov, V. A.; Kraev, G. N.

2017-12-01

Various human footprints on the flux of biogenic greenhouse gases from permafrost-affected soils in Arctic and boreal domains in Russia are considered. Tendencies of significant growth or suppression of soil CO2 fluxes change across types of human impact. Overall, the human impacts increase the mean value and variance of local soil CO2 flux. Human footprint on methane exchange between soil and atmosphere is mediated by drainage. However, all the types of human impact suppress the sources and increase sinks of methane to the land ecosystems. N2O flux grew under the considered types of human impact. Based on the results, we suggest that human footprint on soil greenhouse gases fluxes is comparable to the effect of climate change at an annual to decadal timescales.

Transportation behaviour of fluopicolide and its control effect against Phytophthora capsici in greenhouse tomatoes after soil application.

Science.gov (United States)

Jiang, Lili; Wang, Hongyan; Xu, Hui; Qiao, Kang; Xia, Xiaoming; Wang, Kaiyun

2015-07-01

Fluopicolide, a novel benzamide fungicide, was registered for control of oomycete pathogens, including Phytophthora capsici. In this study, fluopicolide (5% SC) was applied in soil at rates of 1.5, 3 and 6 L ha(-1) [the normal (ND), double (DD) and quadruple dosages (QD) respectively] to investigate its transportation behaviour and control efficiency on tomato blight as a soil treatment agent. The results showed that fluopicolide applied to soil could be absorbed by tomato roots and then transplanted to stems and leaves. It could exist in tomato roots for more than 30 days, and in leaves and stems until day 20 after application. The decline in fluopicolide in soil was in accordance with a first-order dynamics equation, with half-lives of 5.33, 4.75 and 5.42 days for the ND, DD and QD treatments respectively. The control efficiencies of fluopicolide were better with soil application than with spraying application, and the inhibition ratios were 93.02, 97.67 and 100 on day 21 for the ND, DD and QD treatments respectively. Soil application of fluopicolide could control P. capsici in greenhouse tomatoes with high efficiency and long persistence. © 2014 Society of Chemical Industry.

Soil properties, crop production and greenhouse gas emissions from organic and inorganic fertilizer-based arable cropping systems

DEFF Research Database (Denmark)

Chirinda, Ngonidzashe; Olesen, Jørgen Eivind; Porter, John Roy

2010-01-01

Organic and conventional farming practices differ in the use of several management strategies, including use of catch crops, green manure, and fertilization, which may influence soil properties, greenhouse gas emissions and productivity of agroecosystems. An 11-yr-old field experiment on a sandy...... loam soil in Denmark was used to compare several crop rotations with respect to a range of physical, chemical and biological characteristics related to carbon (C) and nitrogen (N) flows. Four organic rotations and an inorganic fertilizer-based system were selected to evaluate effects of fertilizer type...... growth was monitored and grain yields measured at harvest maturity. The different management strategies between 1997 and 2007 led to soil carbon inputs that were on average 18–68% and 32–91% higher in the organic than inorganic fertilizer-based rotations for the sampled winter wheat and spring barley...

Influence of Biochar on C and N Transformation in Soil and Their Impact on Greenhouse Gas Emissions

Science.gov (United States)

Chintala, R.; Schumacher, T. E.; Kumar, S.; Clay, D. E.; Malo, D. D.

2014-12-01

The capacity of pyrogenic biochar to mitigate soil surface exchange of greenhouse gases (GHG) is dependent on the influence of biochar on physiochemical transformations of C and N in soils. Incorporated biochar amendments are hypothesized to interfere with transformations of C and N as a result of the unique recalcitrant chemical structure and surface complexity of biochars. The nature of interference by biochar with C and N transformations are assumed to be dynamic not only due to their highly variable amphilicity inherited from feedstock source and controlled pyrolytic processing parameters but also to variation in soil factors. Experiments comprised of laboratory and field studies were designed to gain insight into the priming effect of incorporated non-native biochar materials on the transformations of C and N species in the soil. Molecular structure and surface functionality of plant based biochar materials produced from carbon optimized gasification of corn stover (Zea mays L.), Ponderosa pine (Pinus ponderosa Lawson and C. Lawson) wood residue, and switchgrass (Panicum virgatum L.) were studied in the laboratory using NMR and SEM-EdX. Biochar materials were found to be highly hydrophobic (low H/C values) with high aromaticity. The surface morphology of all the biochar materials was highly heterogeneous and pore size ranged from 1-22µm with the faces and edges of ordered sheets. In the field study, all the three biochar types were applied at a 1% (w/w) rate to a Maddock soil (Sandy, Mixed, Frigid Entic Hapludolls) located in an eroded upper landscape position and a Brookings soil (Fine-Silty, Mixed, Superactive, Frigid Pachic Hapludolls) located in a depositional landscape position. The crop rotation is a corn (Zea mays L.) followed by soybean (Glycine max L.). The priming effect of biochars on the transformations of C and N is determined by measuring the changes in soil C (total organic carbon, microbial biomass C, hydrolyzable C, and δ 13C) and N pools

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

Energy Technology Data Exchange (ETDEWEB)

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

2016-08-01

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

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

International Nuclear Information System (INIS)

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

2016-01-01

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

Effect of soil texture on phytoremediation of arsenic-contaminated soils

Science.gov (United States)

Pallud, C. E.; Matzen, S. L.; Olson, A.

2015-12-01

Soil arsenic (As) contamination is a global problem, resulting in part from anthropogenic activities, including the use of arsenical pesticides and treated wood, mining, and irrigated agriculture. Phytoextraction using the hyperaccumulating fern Pteris vittata is a promising new technology to remediate soils with shallow arsenic contamination with minimal site disturbance. However, many challenges still lie ahead for a global application of phytoremediation. For example, remediation times using P. vittata are on the order of decades. In addition, most research on As phytoextraction with P. vittata has examined As removal from sandy soils, where As is more available, with little research focusing on As removal from clayey soils, where As is less available. The objective of this study is to determine the effects of soil texture and soil fertilization on As extraction by P. vittata, to optimize remediation efficiency and decrease remediation time under complex field conditions. A field study was established 2.5 years ago in an abandoned railroad grade contaminated with As (average 85.5 mg kg-1) with texture varying from sandy loam to silty clay loam. Organic N, inorganic N, organic P, inorganic P, and compost were applied to separate sub-plots; control ferns were grown in untreated soil. In a parallel greenhouse experiment, ferns were grown in sandy loam soil extracted from the field (180 mg As kg-1), with similar treatments as those used at the field site, plus a high phosphate treatment and treatments with arbuscular mycorrhizal fungi. In the field study, fern mortality was 24% higher in clayey soil than in sandy soil due to waterlogging, while As was primarily associated with sandy soil. Results from the sandy loam soil indicate that soil treatments did not significantly increase As phytoextraction, which was lower in phosphate-treated ferns than in control ferns, both in the field and greenhouse study. Under greenhouse conditions, ferns treated with organic N were

Effect of Miscanthus cultivation on metal fractionation and human bioaccessibility in metal-contaminated soils: comparison between greenhouse and field experiments.

Science.gov (United States)

Pelfrêne, Aurélie; Kleckerová, Andrea; Pourrut, Bertrand; Nsanganwimana, Florien; Douay, Francis; Waterlot, Christophe

2015-02-01

The in situ stabilization of metals in soils using plants with great biomass value is a promising, cost-effective, and ecologically friendly alternative to manage metal-polluted sites. The goal of phytostabilization is to reduce the bioavailable concentrations of metals in polluted soil and thus reduce the risk to the environment and human health. In this context, this study aimed at evaluating Miscanthus × giganteus efficiency in phytostabilizing metals on three contaminated agricultural sites after short-term exposure under greenhouse conditions and after long-term exposure under field conditions. Particular attention was paid to the influence of Miscanthus cultivation on (i) Cd, Pb, and Zn fractionation using sequential extractions and (ii) metal bioaccessibility using an in vitro gastrointestinal digestion test. Data gave evidence of (i) different behaviors between the greenhouse and the field; (ii) metal redistribution in soils induced by Miscanthus culture, more specifically under field conditions; (iii) higher environmental availability for Cd than for Pb and Zn was found in both conditions; and (iv) overall, a higher bioaccessible fraction for Pb (about 80 %) and Cd (65-77 %) than for Zn (36-52 %) was recorded in the gastric phase, with a sharp decrease in the intestinal phase (18-35 % for Cd, 5-30 % for Pb, and 36-52 % for Zn). Compared to soils without culture, the results showed that phytostabilization using Miscanthus culture provided evidence for substantial effects on oral bioaccessibility of Cd, Pb, and Zn.

Turnover and transport of greenhouse gases in a Danish wetland

DEFF Research Database (Denmark)

Jørgensen, Christian Juncher

2011-01-01

involving plants, soil and microorganisms. These processes are regulated by different physio-chemical drivers such as soil moisture content, soil temperature, nutrient and oxygen (O2) availability. In wetlands, the position of the free standing water level (WL) influences the spatiotemporal variation...... in these drivers, thereby influencing the net emission or uptake of greenhouse gas. In this PhD thesis the complex aspects in the exchange of N2O across the soil-atmosphere is investigated with special focus on the spatiotemporal variations in drivers for N2O production and consumption in the soil...... net N2O dynamics. Similarly, plant-mediated gas transport by the subsurface aerating macrophyte Phalaris arundinacea played a major part in regulating and facilitating emissions of greenhouse gases across the soil-atmosphere interface. It is concluded that the spatiotemporal distribution of dominating...

Edaphic factors controlling summer (rainy season) greenhouse gas emissions (CO2 and CH4) from semiarid mangrove soils (NE-Brazil).

Science.gov (United States)

Nóbrega, Gabriel N; Ferreira, Tiago O; Siqueira Neto, M; Queiroz, Hermano M; Artur, Adriana G; Mendonça, Eduardo De S; Silva, Ebenezer De O; Otero, Xosé L

2016-01-15

The soil attributes controlling the CO2, and CH4 emissions were assessed in semiarid mangrove soils (NE-Brazil) under different anthropogenic activities. Soil samples were collected from different mangroves under different anthropogenic impacts, e.g., shrimp farming (Jaguaribe River); urban wastes (Cocó River) and a control site (Timonha River). The sites were characterized according to the sand content; physicochemical parameters (Eh and pH); total organic C; soil C stock (SCS) and equivalent SCS (SCSEQV); total P and N; dissolved organic C (DOC); and the degree of pyritization (DOP). The CO2 and CH4 fluxes from the soils were assessed using static closed chambers. Higher DOC and SCS and the lowest DOP promote greater CO2 emission. The CH4 flux was only observed at Jaguaribe which presented higher DOP, compared to that found in mangroves from humid tropical climates. Semiarid mangrove soils cannot be characterized as important greenhouse gas sources, compared to humid tropical mangroves.

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

Science.gov (United States)

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

2016-01-01

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

Optimal space utilization of a greenhouse using multi-rack tray system: Thermal modeling and experimental validation

International Nuclear Information System (INIS)

Sethi, V.P.; Dubey, R.K.

2008-01-01

In this study, upper space inside an east-west oriented greenhouse (where the micro-climate is also under control) is optimised for producing maximum number of nursery plants by developing a multi-rack tray system (MRTS). The MRTS is designed in such a way that the vertical distance between the two consecutive trays (H) and width of the tray (W) is optimised for different months of the year at different latitudes so that the shadow of the upper tray does not fall on the lower one. The number of stacks in a greenhouse of fixed height (say 4 m) is a direct function of the maximum altitude angle of the sun at noon (α s ) at particular latitude. It is observed that at 10 deg. N and 20 deg. N latitudes α s remains greater than 45 deg. (H/W > 1) even during the winter months. It means not more than two stacks are possible inside a 4 m high greenhouse during December and January. The computations show that at 30 deg. N, 40 deg. N and 50 deg. N latitude, the number of stacks inside a greenhouse can be five, seven and twelve, respectively during the winter months of December and January. A transient thermal model coupled with MRTS is also developed to predict the soil, plant and air temperature inside the greenhouse. It is observed that the predicted and measured values are in close agreement. It is also observed that due to the increased mass of soil (in the trays) inside the greenhouse and due to reduced conduction losses to the ground beneath, MRTS also acted as a soil heat storage system before germination of the plants which stored heat during the sun-shine hours and released the same during the off-shine hours and resulted in 5-2deg. C higher inside air temperature till the early night hours as compared to ambient air temperature. Nursery of marigold (ornamental plant) is successfully raised using the MRTS inside a 3 m high greenhouse having three stacks at 30 deg. N latitude. Experiments showed that there was almost uniform growth of plants in all the three trays

Tree species effects on soil properties and greenhouse gas fluxes in East-central Amazonia: comparison between monoculture and diverse forest

Science.gov (United States)

J. Van Haren; R.C. de Oliveira, Jr.; P.T. Beldini; P.B. de Camargo; M. Keller; S. Saleska

2013-01-01

Tropical plantations are considered a viable option to sequester carbon on abandoned agricultural lands, but implications of tree species selection for overall greenhouse gas budgets on plantations have been little studied. During three wet seasons, we investigated the influence of nine tree species on soil pH, temperature (ST), bulk density (BD), moisture content...

Automatically Maintain Climatic Conditions inside Agricultural Greenhouses

Directory of Open Access Journals (Sweden)

Ali Jasim Ramadhan

2016-11-01

Full Text Available In this work, a novel system is designed to remote monitor / automatic control of the temperature, humidity and soil moisture of the agricultural greenhouses. In the proposed system, the author used the mentioned sensors for monitoring the climatic conditions of the agricultural greenhouses; and the system makes a controlling process to fix the required parameters for plant growth by running / stopping the fan, air exchanger and irrigation devices when any changes happened in these parameters. The presented system is based on XBee protocol in the implemented wireless sensor star topology network (WSN to monitor the agricultural greenhouses in real time, and used the GSM and Internet technologies to monitor the agricultural greenhouses from anywhere.

Biochar: from laboratory mechanisms through the greenhouse to field trials

Science.gov (United States)

Masiello, C. A.; Gao, X.; Dugan, B.; Silberg, J. J.; Zygourakis, K.; Alvarez, P. J. J.

2014-12-01

The biochar community is excellent at pointing to individual cases where biochar amendment has changed soil properties, with some studies showing significant improvements in crop yields, reduction in nutrient export, and remediation of pollutants. However, many studies exist which do not show improvements, and in some cases, studies clearly show detrimental outcomes. The next, crucial step in biochar science and engineering research will be to develop a process-based understanding of how biochar acts to improve soil properties. In particular, we need a better mechanistic understanding of how biochar sorbs and desorbs contaminants, how it interacts with soil water, and how it interacts with the soil microbial community. These mechanistic studies need to encompass processes that range from the nanometer to the kilometer scale. At the nanometer scale, we need a predictive model of how biochar will sorb and desorb hydrocarbons, nutrients, and toxic metals. At the micrometer scale we need models that explain biochar's effects on soil water, especially the plant-available fraction of soil water. The micrometer scale is also where mechanistic information is neeed about microbial processes. At the macroscale we need physical models to describe the landscape mobility of biochar, because biochar that washes away from fields can no longer provide crop benefits. To be most informative, biochar research should occur along a lab-greenhouse-field trial trajectory. Laboratory experiments should aim determine what mechanisms may act to control biochar-soil processes, and then greenhouse experiments can be used to test the significance of lab-derived mechanisms in short, highly replicated, controlled experiments. Once evidence of effect is determined from greenhouse experiments, field trials are merited. Field trials are the gold standard needed prior to full deployment, but results from field trials cannot be extrapolated to other field sites without the mechanistic backup provided

Redox potential characterization and soil greenhouse gas concentration across a hydrological gradient in a Gulf coast forest

Science.gov (United States)

Yu, K.; Faulkner, S.P.; Patrick, W.H.

2006-01-01

Soil redox potential (Eh), concentrations of oxygen (O2) and three greenhouse gases (CO2, CH4, and N2O) were measured in the soil profile of a coastal forest at ridge, transition, and swamp across a hydrological gradient. The results delineated a distinct boundary in soil Eh and O2 concentration between the ridge and swamp with essentially no overlap between the two locations. Critical soil Eh to initiate significant CH4 production under this field conditions was about +300 mV, much higher than in the homogenous soils (about -150 mV). The strength of CH4 source to the atmosphere was strong for the swamp, minor for the transition, and negligible or even negative (consumption) for the ridge. Maximum N2O concentration in the soils was found at about Eh +250 mV, and the soil N2O emission was estimated to account for less than 4% for the ridge and transition, and almost negligible for the swamp in the cumulative global warming potential (GWP) of these three gases. The dynamic nature of this study site in response to water table fluctuations across a hydrological gradient makes it an ideal model of impact of future sea level rise to coastal ecosystems. Soil carbon (C) sequestration potential due to increasing soil water content upon sea level rise and subsidence in this coastal forest was likely limited and temporal, and at the expense of increasing soil CH4 production and emission. ?? 2005 Elsevier Ltd. All rights reserved.

Devosia soli sp. nov., isolated from greenhouse soil in Korea.

Science.gov (United States)

Yoo, Seung-Hee; Weon, Hang-Yeon; Kim, Byung-Yong; Hong, Seung-Beom; Kwon, Soon-Wo; Cho, Yang-Hee; Go, Seung-Joo; Stackebrandt, Erko

2006-11-01

A Gram-negative, obligately aerobic, rod-shaped bacterium was isolated from greenhouse soil used to cultivate lettuce. The strain, GH2-10T, was characterized on the basis of phenotypic and genotypic data. 16S rRNA gene sequence analysis revealed that the isolate belonged to the genus Devosia, with highest sequence similarity (98.5%) to Devosia riboflavina IFO 13584T. Sequence similarities with other strains tested were below 97.0%. Strain GH2-10T had Q-10 as the predominant ubiquinone and C18:1omega7c and C16:0 as the major fatty acids. The G+C content of the genomic DNA was 59.5 mol%. The results of DNA-DNA hybridization experiments (47% relatedness between D. riboflavina DSM 7230T and strain GH2-10T) and physiological and biochemical tests suggested that strain GH2-10T represents a novel species of the genus Devosia, for which the name Devosia soli sp. nov. is proposed. The type strain is GH2-10T (=KACC 11509T=DSM 17780T).

Agricultural sources of greenhouse gas emissions

International Nuclear Information System (INIS)

Rochette, P.

2003-01-01

The author described different sources of greenhouse gas emissions resulting from agricultural activities and the process by which carbon dioxide, nitrous oxide, and methane are generated on Canadian farms. The author also proposed some practices that would contribute to the reduction of greenhouse gas emissions. A brief description of the greenhouse effect was also provided with special emphasis on the agricultural sector. In 1996, the Canadian agricultural sector was responsible for approximately 10 per cent of greenhouse gas emissions in the country. Given the increase in farm animals and more intensive agricultural activities, it is estimated that greenhouse gas emissions generated by the agricultural sector will increase by 20 per cent by 2010 if current practices remain in effect. The most optimistic scenarios indicate that the agricultural sector could achieve or even exceed Canada's Kyoto Protocol commitments mainly through organic material sequestration in soils. The possibility for farmers to sell greenhouse gas credits could motivate farmers into adopting various practices that reduce emissions of greenhouse gases. However, the author indicated that the best motivation for farmers is the fact that adopting such practices would also lead to more efficient agricultural production. 5 refs., 4 figs

Changes on sewage sludge stability after greenhouse drying

Science.gov (United States)

Soriano-Disla, J. M.; Houot, S.; Imhoff, M.; Valentin, N.; Gómez, I.; Navarro-Pedreño, J.

2009-04-01

The progressive implementation of the Urban Waste Water Treatment Directive 91/271/EEC in all the European member states is increasing the quantities of sewage sludge requiring disposal. Sludge application onto cultivated soils as organic fertilizers allows the recycling of nutrients. The application of only dehydrated sludges has generated many problems including unpleasant odours and difficult management (regarding transport and application) related to their high water content. One way to overcome these problems, in a cheap and clean way, is the drying of sludges using the energy of the sun under greenhouse conditions. This drying may affect sludge chemical characteristics including organic matter stability and nitrogen availability, parameters which have to be controlled for the proper management of dry sludge application onto soils. For this reason, the main aim of this work was to study the impact of greenhouse drying of different sewage sludges on their organic matter stability and nitrogen availability, assessed by biochemical fractionation and mineralization assays. Three sewage sludges were sampled before (dehydrated sludges) and after greenhouse drying (dried sludges). The analyses consisted of: humidity, organic matter, mineral and organic N contents, N and C mineralization during 91-day laboratory incubations in controlled conditions, and biochemical fractionation using the Van Soest procedure. Greenhouse drying decreased the water content from 70-80% to 10% and also the odours, both of which will improve the management of the final product from the perspective of application and transport. We also found that drying reduced the organic matter content of the sludges but not the biodegradability of the remaining carbon. Organic N mineralization occurred during greenhouse drying, explaining why mineral N content tended to increase and the potential mineralization of organic nitrogen decreased after greenhouse drying. The biochemical stability did not

Competitiveness of terrestrial greenhouse gas offsets. Are they a bridge to the future?

International Nuclear Information System (INIS)

McCarl, B.A.; Sands, R.D.

2007-01-01

Activities to reduce net greenhouse gas emissions by biological soil or forest carbon sequestration predominantly utilize currently known, readily implementable technologies. Many other greenhouse gas emission reduction options require future technological development or must wait for turnover of capital stock. Carbon sequestration options in soils and forests, while ready to go now, generally have a finite life, allowing use until other strategies are developed. This paper reports on an investigation of the competitiveness of biological carbon sequestration from a dynamic and multiple strategy viewpoint. Key factors affecting the competitiveness of terrestrial mitigation options are land availability and cost effectiveness relative to other options including CO2 capture and storage, energy efficiency improvements, fuel switching, and non-CO2 greenhouse gas emission reductions. The analysis results show that, at lower CO2 prices and in the near term, soil carbon and other agricultural/forestry options can be important bridges to the future, initially providing a substantial portion of attainable reductions in net greenhouse gas emissions, but with a limited role in later years. At higher CO2 prices, afforestation and biofuels are more dominant among terrestrial options to offset greenhouse gas emissions. But in the longer run, allowing for capital stock turnover, options to reduce greenhouse gas emissions from the energy system and biofuels provide an increasing share of potential reductions in total US greenhouse gas emissions

Nitrogen availability and indirect measurements of greenhouse gas emissions from aerobic and anaerobic biowaste digestates applied to agricultural soils

International Nuclear Information System (INIS)

Rigby, H.; Smith, S.R.

2013-01-01

, indicating greater microbial activity in amended soil and reflecting the lower stability of this OM source, compared to the other, anaerobic digestate types, which showed no consistent effects on MBN compared to the control. Thus, the overall net release of digestate N in different soil types was not regulated by N transfer into the soil microbial biomass, but was determined primarily by digestate properties and the capacity of the soil type to process and turnover digestate N. In contrast to the sandy soil types, where nitrate (NO 3 - ) concentrations increased during incubation, there was an absence of NO 3 - accumulation in the silty clay soil amended with LTAD and DMADMSW. This provided indirect evidence for denitrification activity and the gaseous loss of N, and the associated increased risk of greenhouse gas emissions under certain conditions of labile C supply and/or digestate physical structure in fine-textured soil types. The significance and influence of the interaction between soil type and digestate stability and physical properties on denitrification processes in digestate-amended soils require urgent investigation to ensure management practices are appropriate to minimise greenhouse gas emissions from land applied biowastes

Nitrogen availability and indirect measurements of greenhouse gas emissions from aerobic and anaerobic biowaste digestates applied to agricultural soils

Energy Technology Data Exchange (ETDEWEB)

Rigby, H.; Smith, S.R., E-mail: s.r.smith@imperial.ac.uk

2013-12-15

, indicating greater microbial activity in amended soil and reflecting the lower stability of this OM source, compared to the other, anaerobic digestate types, which showed no consistent effects on MBN compared to the control. Thus, the overall net release of digestate N in different soil types was not regulated by N transfer into the soil microbial biomass, but was determined primarily by digestate properties and the capacity of the soil type to process and turnover digestate N. In contrast to the sandy soil types, where nitrate (NO{sub 3}{sup -}) concentrations increased during incubation, there was an absence of NO{sub 3}{sup -} accumulation in the silty clay soil amended with LTAD and DMADMSW. This provided indirect evidence for denitrification activity and the gaseous loss of N, and the associated increased risk of greenhouse gas emissions under certain conditions of labile C supply and/or digestate physical structure in fine-textured soil types. The significance and influence of the interaction between soil type and digestate stability and physical properties on denitrification processes in digestate-amended soils require urgent investigation to ensure management practices are appropriate to minimise greenhouse gas emissions from land applied biowastes.

A greenhouse study of northern red oak seedling growth on two forest soils at different stages of acidification

International Nuclear Information System (INIS)

Sharpe, W.E.; Swistock, B.R.; Dewalle, D.R.

1993-01-01

The objective of this study was to determine whether or not Ca and P in soils from two forested sites at two different stages of acidification were limiting growth of red oak seedlings. The A and E horizons of a Berks soils from Watershed 4 at the Fernow Experimental Forest (cation exchange buffer range) and a Hazelton-Dekalb soil from Pea Vine Hill in Southwestern Pennsylvania (A1 buffer range) were placed in pots and utilized as the growth medium for northern red oak seedlings in a greenhouse environment. Soil water NO 3 -N, Ca, Mg and K concentrations were significantly higher on the Berks soil. Soil exchangeable P and soil solution TP (total phosphorus) were significantly higher on the Hazelton-Dekalb soil. Both soils were amended with bone meal (CaPO 4 ) to determine the effects of Ca and P addition on the growth and nutrient uptake of the seedlings. Height growth of the control red oak seedlings was significantly greater on the Berks soil after 45 d, but amendment of Hazelton-Dekalb soils with bone meal eliminated this difference. Bone meal addition to the Hazelton-Dekalb soil resulted in significantly greater height growth of red oak seedlings when compared to red oak seedings grown on unamended Hazelton-Dekalb soil, but did not have a similar effect for red oak seedlings grown on Berks soil. Bone meal addition to Hazelton-Dekalb soil resulted in greater concentrations of Ca and Mg in red oak leaves. Unfertilized Berks red oak seedling leaves had significantly higher concentrations of Ca and K than their Hazelton-Dekalb counterparts. Al-Ca molar ratios were significantly lower on the Berks soil. Red oak height growth was increased significantly by Ca addition to the Hazelton-Dekalb soil. 24 refs., 2 figs., 8 tabs

Response of Soil Biogeochemistry to Freeze-thaw Cycles: Impacts on Greenhouse Gas Emission and Nutrient Fluxes

Science.gov (United States)

Rezanezhad, F.; Parsons, C. T.; Smeaton, C. M.; Van Cappellen, P.

2014-12-01

Freeze-thaw is an abiotic stress applied to soils and is a natural process at medium to high latitudes. Freezing and thawing processes influence not only the physical properties of soil, but also the metabolic activity of soil microorganisms. Fungi and bacteria play a crucial role in soil organic matter degradation and the production of greenhouse gases (GHG) such as CO2, CH4 and N2O. Production and consumption of these atmospheric trace gases are the result of biological processes such as photosynthesis, aerobic respiration (CO2), methanogenesis, methanotrophy (CH4), nitrification and denitrification (N2O). To enhance our understanding of the effects of freeze-thaw cycles on soil biogeochemical transformations and fluxes, a highly instrumented soil column experiment was designed to realistically simulate freeze-thaw dynamics under controlled conditions. Pore waters collected periodically from different depths of the column and solid-phase analyses on core material obtained at the initial and end of the experiment highlighted striking geochemical cycling. CO2, CH4 and N2O production at different depths within the column were quantified from dissolved gas concentrations in pore water. Subsequent emissions from the soil surface were determined by direct measurement in the head space. Pulsed CO2 emission to the headspace was observed at the onset of thawing, however, the magnitude of the pulse decreased with each subsequent freeze-thaw cycle indicating depletion of a "freeze-thaw accessible" carbon pool. Pulsed CO2 emission was due to a combination of physical release of gases dissolved in porewater and entrapped below the frozen zone and changing microbial respiration in response to electron acceptor variability (O2, NO3-, SO42-). In this presentation, we focus on soil-specific physical, chemical, microbial factors (e.g. redox conditions, respiration, fermentation) and the mechanisms that drive GHG emission and nutrient cycling in soils under freeze-thaw cycles.

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

Directory of Open Access Journals (Sweden)

Ariadna eGiné

2016-02-01

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

Agronomic behavior of phosphoric rock from Bahia Inglesa using isotopic techniques. 2. Greenhouse experiment in three volcanic ash soils

International Nuclear Information System (INIS)

Pino N, I.; Casas G, L.

1989-01-01

With the aim to evaluate the behaviour of phosphoric rock in regard to the sorption capacity from three volcanic ash soils, a greenhouse trial was carried out. The isotopic dilution method with triple superphosphate labeled P32 (TSP-32) was used. Total dry matter, P total was determined by colorimetry and the liquid scintillation method for P32 was used. The evaluation of the rock was measured through different isotopical parameters such as A value and P derived from the rock. The behaviour of this material was affected by the different properties of the soils mainly on account of the diverse sorption capacity of them giving an inverse relation among sorption and effectiveness of the rock. The results showed a higher efficiency of TSP for the three soils compared with the phosphoric rock either concentrated or not. (author)

The Greenhouse and Anti-Greenhouse Effects on Titan

Science.gov (United States)

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

1994-01-01

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

Effects of land use on greenhouse gas fluxes and soil properties of wetland catchments in the Prairie Pothole Region of North America

International Nuclear Information System (INIS)

Tangen, Brian A.; Finocchiaro, Raymond G.; Gleason, Robert A.

2015-01-01

Wetland restoration has been suggested as policy goal with multiple environmental benefits including enhancement of atmospheric carbon sequestration. However, there are concerns that increased methane (CH 4 ) emissions associated with restoration may outweigh potential benefits. A comprehensive, 4-year study of 119 wetland catchments was conducted in the Prairie Pothole Region of the north-central U.S. to assess the effects of land use on greenhouse gas (GHG) fluxes and soil properties. Results showed that the effects of land use on GHG fluxes and abiotic soil properties differed with respect to catchment zone (upland, wetland), wetland classification, geographic location, and year. Mean CH 4 fluxes from the uplands were predictably low (< 0.02 g CH 4 m −2 day −1 ), while wetland zone CH 4 fluxes were much greater (< 0.001–3.9 g CH 4 m −2 day −1 ). Mean cumulative seasonal CH 4 fluxes ranged from roughly 0–650 g CH 4 m −2 , with an overall mean of approximately 160 g CH 4 m −2 . These maximum cumulative CH 4 fluxes were nearly 3 times as high as previously reported in North America. The overall magnitude and variability of N 2 O fluxes from this study (< 0.0001–0.0023 g N 2 O m −2 day −1 ) were comparable to previously reported values. Results suggest that soil organic carbon is lost when relatively undisturbed catchments are converted for agriculture, and that when non-drained cropland catchments are restored, CH 4 fluxes generally are not different than the pre-restoration baseline. Conversely, when drained cropland catchments are restored, CH 4 fluxes are noticeably higher. Consequently, it is important to consider the type of wetland restoration (drained, non-drained) when assessing restoration benefits. Results also suggest that elevated N 2 O fluxes from cropland catchments likely would be reduced through restoration. The overall variability demonstrated by this study was consistent with findings of other wetland investigations and

Strategies to Optimize Microbially-Mediated Mitigation of Greenhouse Gas Emissions from Landfill Cover Soils

Energy Technology Data Exchange (ETDEWEB)

Jeremy Semrau; Sung-Woo Lee; Jeongdae Im; Sukhwan Yoon; Michael Barcelona

2010-09-30

The overall objective of this project, 'Strategies to Optimize Microbially-Mediated Mitigation of Greenhouse Gas Emissions from Landfill Cover Soils' was to develop effective, efficient, and economic methodologies by which microbial production of nitrous oxide can be minimized while also maximizing microbial consumption of methane in landfill cover soils. A combination of laboratory and field site experiments found that the addition of nitrogen and phenylacetylene stimulated in situ methane oxidation while minimizing nitrous oxide production. Molecular analyses also indicated that methane-oxidizing bacteria may play a significant role in not only removing methane, but in nitrous oxide production as well, although the contribution of ammonia-oxidizing archaea to nitrous oxide production can not be excluded at this time. Future efforts to control both methane and nitrous oxide emissions from landfills as well as from other environments (e.g., agricultural soils) should consider these issues. Finally, a methanotrophic biofiltration system was designed and modeled for the promotion of methanotrophic activity in local methane 'hotspots' such as landfills. Model results as well as economic analyses of these biofilters indicate that the use of methanotrophic biofilters for controlling methane emissions is technically feasible, and provided either the costs of biofilter construction and operation are reduced or the value of CO{sub 2} credits is increased, can also be economically attractive.

The use of 32p labelled fertilizer in field and greenhouse

Energy Technology Data Exchange (ETDEWEB)

NONE

1983-12-31

This training film deals with the use of 32p-labelled materials in field and greenhouse experimentation in soil-plant relationship studies. All technical aspects, including safe handling and radiation protection procedures to be considered in the layout and harvesting of field experiments are documented in detail. Procedures followed in the evaluation of P fertilizers (such as rock phosphates) under greenhouse conditions are described. Several soil injection techniques available for the determination of the root activity pattern of trees are shown

Land Use Effects on Net Greenhouse Gas Fluxes in the US Great Plains: Historical Trends and Model Projections

Science.gov (United States)

Del Grosso, S. J.; Parton, W. J.; Ojima, D. S.; Mosier, A. R.; Mosier, A. R.; Paustian, K.; Peterson, G. A.

2001-12-01

We present maps showing regional patterns of land use change and soil C levels in the US Great Plains during the 20th century and time series of net greenhouse gas fluxes associated with different land uses. Net greenhouse gas fluxes were calculated by accounting for soil CO2 fluxes, the CO2 equivalents of N2O emissions and CH4 uptake, and the CO2 costs of N fertilizer production. Both historical and modern agriculture in this region have been net sources of greenhouse gases. The primary reason for this, prior to 1950, is that agriculture mined soil C and resulted in net CO2 emissions. When chemical N fertilizer became widely used in the 1950's agricultural soils began to sequester CO2-C but these soils were still net greenhouse gas sources if the effects of increased N2O emissions and decreased CH4 uptake are included. The sensitivity of net greenhouse gas fluxes to conventional and alternative land uses was explored using the DAYCENT ecosystem model. Model projections suggest that conversion to no-till, reduction of the fallow period, and use of nitrification inhibitors can significantly decrease net greenhouse gas emissions in dryland and irrigated systems, while maintaining or increasing crop yields.

Biochars mitigate greenhouse gas emissions and bioaccumulation of potentially toxic elements and arsenic speciation in Phaseolus vulgaris L.

Science.gov (United States)

Ibrahim, Muhammad; Li, Gang; Khan, Sardar; Chi, Qiaoqiao; Xu, Yaoyang; Zhu, Yongguan

2017-08-01

Anthropogenic and natural activities can lead to increased greenhouse gas emissions and discharge of potentially toxic elements (PTEs) into soil environment. Biochar amendment to soils is a cost-effective technology and sustainable approach used to mitigate greenhouse gas emissions, improve phytoremediation, and minimize the health risks associated with consumption of PTE-contaminated vegetables. Greenhouse pot experiments were conducted to investigate the effects of peanut shell biochar (PNB) and sewage sludge biochar (SSB) on greenhouse gas (GHG) emissions, plant growth, PTE bioaccumulation, and arsenic (As) speciation in bean plants. Results indicated that amendments of PNB and SSB increased plant biomass production by increasing soil fertility and reducing bioavailability of PTEs. Addition of biochars also increased soil pH, total nitrogen (TN), total carbon (TC), dissolved organic carbon (DOC), and ammonium-nitrogen (NH 4 -N) but decreased available concentrations of PTEs such as cadmium (Cd), lead (Pb), and As. The concentration of nitrate-nitrogen (NO 3 - -N) was also decreased in biochar-amended soils. In addition, PNB and SSB amendments significantly (P Greenhouse gases such as carbon dioxide (CO 2 ) and methane (CH 4 ) emissions were significantly (P greenhouse gas emissions and PTE bioaccumulation as well as arsenic speciation in P. vulgaris L.

Soil Greenhouse Gas Fluxes in a Pacific Northwest Douglas-Fir Forest: Results from a Soil Fertilization and Biochar Addition Experiment

Science.gov (United States)

Hawthorne, I.; Johnson, M. S.; Jassal, R. S.; Black, T. A.

2013-12-01

Rising atmospheric concentrations of greenhouse gases (GHGs), carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O), linked to current climate change has stimulated a scientific response to provide robust accounting of sources and sinks of these gases. There is an urgent need to increase awareness of land management impacts on GHG flux dynamics to facilitate the development of management strategies that minimize GHG emissions. Biochar (pyrolyzed organic matter) has been identified as a strategy to reduce net GHG fluxes from soils. This is due to its potential to sequester large amounts of carbon for significant time periods, as well as its modification of biotic and abiotic soil conditions, which in turn can alter the GHG balance. This study describes the effect of biochar and urea-N application on soil surface CO2, CH4 and N2O fluxes in a Pacific Northwest Douglas-fir forest on Vancouver Island, BC, Canada (49o 52' N, 125o 20' W). We used a randomized complete-block design with four replicates of the following treatments: i) control, ii) 5 Mg ha-1 biochar surface application, iii) 200 kg N ha-1 urea pellets surface application, and iv) 5 Mg ha-1 biochar plus 200 kg N ha-1 urea. Soil GHG flux measurements were made biweekly for two years beginning in September 2011 using a non-steady-state non-flow through chamber technique. Biochar was added in February 2012, with urea applied in March 2013. A collar made from 21-cm diameter x 11-cm long PVC piping was installed in each of the 16 plots between two large trees on the forest floor, penetrating the organic layer to the mineral soil at the 5-8 cm depth. A clear Plexiglas lid, equipped with a 10-cm long vent tube and 9-V fan, was placed on each collar when making measurements, with 20-mL samples of chamber headspace air collected at 0, 3, 6, 9 and 12 min using a medical syringe with 21-gauge needle inserted through a rubber septum in the chamber lid. Samples were injected into and transported in previously

No Effect Level of Co-Composted Biochar on Plant Growth and Soil Properties in a Greenhouse Experiment

Directory of Open Access Journals (Sweden)

Hardy Schulz

2014-01-01

Full Text Available It is claimed that the addition of biochar to soil improves C sequestration, soil fertility and plant growth, especially when combined with organic fertilizers such as compost. However, little is known about agricultural effects of small amounts of composted biochar. This greenhouse study was carried out to examine effects of co-composted biochar on oat (Avena sativa L. yield in both sandy and loamy soil. The aim of this study was to test whether biochar effects can be observed at very low biochar concentrations. To test a variety of application amounts below 3 Mg biochar ha−1, we co-composted five different biochar concentrations (0, 3, 5, 10 kg Mg−1 compost. The biochar-containing compost was applied at five application rates (10, 50, 100, 150, 250 Mg ha−1 20 cm−1. Effects of compost addition on plant growth, Total Organic Carbon, Ntot, pH and soluble nutrients outweighed the effects of the minimal biochar amounts in the composted substrates so that a no effect level of biochar of at least 3 Mg ha−1 could be estimated.

Impacts of soil incorporation of pre-incubated silica-rich rice residue on soil biogeochemistry and greenhouse gas fluxes under flooding and drying.

Science.gov (United States)

Gutekunst, Madison Y; Vargas, Rodrigo; Seyfferth, Angelia L

2017-09-01

Incorporation of silica-rich rice husk residue into flooded paddy soil decreases arsenic uptake by rice. However, the impact of this practice on soil greenhouse gas (GHG) emissions and elemental cycling is unresolved particularly as amended soils experience recurrent flooding and drying cycles. We evaluated the impact of pre-incubated silica-rich rice residue incorporation to soils on pore water chemistry and soil GHG fluxes (i.e., CO 2 , CH 4 , N 2 O) over a flooding and drying cycle typical of flooded rice cultivation. Soils pre-incubated with rice husk had 4-fold higher pore water Si than control and 2-fold higher than soils pre-incubated with rice straw, whereas the pore water As and Fe concentrations in soils amended with pre-incubated straw and husk were unexpectedly similar (maximum ~0.85μM and ~450μM levels, respectively). Pre-incubation of residues did not affect Si but did affect the pore water levels of As and Fe compared to previous studies using fresh residues where straw amended soils had higher As and Fe in pore water. The global warming potential (GWP) of soil GHG emissions decreased in the order straw (612±76g CO 2 -eqm -2 )>husk (367±42gCO 2 -eqm -2 )>ashed husk=ashed straw (251±26 and 278±28gCO 2 -eqm -2 )>control (186±23gCO 2 -eqm -2 ). The GWP increase due to pre-incubated straw amendment was due to: a) larger N 2 O fluxes during re-flooding; b) smaller contributions from larger CH 4 fluxes during flooded periods; and c) higher CH 4 and CO 2 fluxes at the onset of drainage. In contrast, the GWP of the husk amendment was dominated by CO 2 and CH 4 emissions during flooded and drainage periods, while ashed amendments increased CO 2 emissions particularly during drainage. This experiment shows that ashed residues and husk addition minimizes GWP of flooded soils and enhances pore water Si compared to straw addition even after pre-incubation. Copyright © 2017 Elsevier B.V. All rights reserved.

The influence of rolled erosion control systems on soil temperature and surface albedo: part I. A greenhouse experiment

International Nuclear Information System (INIS)

Sutherland, R.A.; Menard, T.; Perry, J.L.; Penn, D.C.

1998-01-01

A greenhouse study examined the influences of various surface covers (a bare control soil and seven rolled erosion control systems—RECS) on surface radiative properties, and soil temperature. In our companion paper we examine relationships with soil moisture, biomass production, and nutrient assimilation. Randomization and replication were key components to our study of microclimate under tropical radiation conditions. The bare Oxisol control soil exhibited the most extreme microclimatic conditions with the lowest albedo (not significantly different from that of P300© North American Green, a dark green polypropylene system), and the highest mean and maximum hourly temperatures recorded at depths of 5 and 8 cm. This hostile climatic environment was not conducive to biomass production or moisture storage and it is likely that the observed soil surface crusts impeded plant emergence. Rolled erosion control systems, on the other hand, generally moderated soil temperatures by reflecting more shortwave radiation, implying less heat energy at the surface for conduction to the soil. The result was that RECS exhibited lower mean soil temperatures, higher minimum temperatures and lower maximum soil temperatures. An aspen excelsior system (Curlex I© Excelsior) had the highest albedo and the soil beneath this system exhibited the greatest temperature modulation. Open-weave systems composed of jute (Geojute© Price & Pictures) and coconut fibers (BioD-Mat 70© RoLanka) were the RECS most similar in temperature response to the bare control soil. Other systems examined were intermediate in their temperature response and surface albedo (i.e., SC150BN© North American Green, C125© North American Green and Futerra© Conwed Fibers). (author)

Edaphic factors controlling summer (rainy season) greenhouse gas emissions (CO_2 and CH_4) from semiarid mangrove soils (NE-Brazil)

International Nuclear Information System (INIS)

Nóbrega, Gabriel N.; Ferreira, Tiago O.; Siqueira Neto, M.; Queiroz, Hermano M.; Artur, Adriana G.; Mendonça, Eduardo De S.; Silva, Ebenezer De O.

2016-01-01

The soil attributes controlling the CO_2, and CH_4 emissions were assessed in semiarid mangrove soils (NE-Brazil) under different anthropogenic activities. Soil samples were collected from different mangroves under different anthropogenic impacts, e.g., shrimp farming (Jaguaribe River); urban wastes (Cocó River) and a control site (Timonha River). The sites were characterized according to the sand content; physicochemical parameters (Eh and pH); total organic C; soil C stock (SCS) and equivalent SCS (SCS_E_Q_V); total P and N; dissolved organic C (DOC); and the degree of pyritization (DOP). The CO_2 and CH_4 fluxes from the soils were assessed using static closed chambers. Higher DOC and SCS and the lowest DOP promote greater CO_2 emission. The CH_4 flux was only observed at Jaguaribe which presented higher DOP, compared to that found in mangroves from humid tropical climates. Semiarid mangrove soils cannot be characterized as important greenhouse gas sources, compared to humid tropical mangroves. - Highlights: • GHG emission was associated with different soil characteristics. • Highest CO_2 emissions were found in mangroves with larger dissolved C and lower DOP. • Less CH_4 flux was due to low DOP in semiarid mangrove soils.

Household scale of greenhouse design in Merauke

Science.gov (United States)

Alahudin, Muchlis; Widarnati, Indah; Luh Sri Suryaningsih, Ni

2018-05-01

Merauke is one of the areas that still use conventional methods in agriculture, The agricultural business does not run the maximum during the year because agricultural products quite difficult to obtain in the market. In the rainy season, the intensity of rain is very high, the water condition is abundant and hard to be channeled due to topography/soil contour conditions average, otherwise in the dry season the water is quite difficult to obtain. The purpose of this research is to compare the thermal conditions between greenhouse with auvplastic and plastic bottle roof.This research is experimental, measurement of thermal conditions in Greenhouse using measuring weather station.Greenhouse design with Quonset type with area of 24 m2The result of this research are greenhouse with paranet + UV plastic roof has an average temperature of 28.7 °C, 70.4% humidity and 0.5 m/s wind speed, while the greenhouse with paranet + plastic bottle roof has an average temperature of 26, 2 °C, humidity 66.4% and wind speed 0.9 m/s. Conclusion is Greenhouse with paranet + plastic bottle roof more thermally comfortable than greenhouse with paranet + UV plastic roof.

Agronomical and biological results of solar energy heating by the combination of the sunstock system with an outside captor on a muskmelon crop grown in polyethylene greenhouses

Directory of Open Access Journals (Sweden)

Vandevelde, R.

1983-01-01

Full Text Available Six cultivars of muskmelon (Early Dew, "68-02", "Early Chaca", "Jivaro", "Super Sprint" and "Cantor" transplanted at two differents dates were cultivated under two PE greenhouses heated by solar energy recovery and compared to a control greenhouse. The greenhouses were covered with a double shield of normal PE of 100 microns. The first greenhouse was considered as the control. The second one was equipped with a sunstock solar energy collector distribution system, consisting in a covering of 37 % of the ground surface by flat black PVC tubes, used during the day as a solar energy captor for heating the water of a basin and during the night as a radiant mulch for heating the greenhouse by emission of radiation warmth. The third greenhouse was equipped also with the same sunstock System, but connected with a supplementary outdoor collector by means of flat PE tubes corresponding to about 28 % covering of the greenhouse, and resulting in a more important energy stock, available for heating during the night. Minimum air temperature was raised by about 1, 5 and 2, 5°C respectively in the second and the third greenhouse, while the minimum soil temperature was raised with about 1 and 2°C respectively. Evolution of the maximum temperatures was more irregular and was depending also from the incident energy. Plant growth under the solar heated greenhouse was more accelerated, and resulted in an earlier fruitset, an earlier production and a higher total yield.

Organic vs. organic - soil arthropods as bioindicators of ecological sustainability in greenhouse system experiment under Mediterranean conditions.

Science.gov (United States)

Madzaric, Suzana; Ceglie, F G; Depalo, L; Al Bitar, L; Mimiola, G; Tittarelli, F; Burgio, G

2017-11-23

Organic greenhouse (OGH) production is characterized by different systems and agricultural practices with diverse environmental impact. Soil arthropods are widely used as bioindicators of ecological sustainability in open field studies, while there is a lack of research on organic production for protected systems. This study assessed the soil arthropod abundance and diversity over a 2-year crop rotation in three systems of OGH production in the Mediterranean. The systems under assessment differed in soil fertility management: SUBST - a simplified system of organic production, based on an input substitution approach (use of guano and organic liquid fertilizers), AGROCOM - soil fertility mainly based on compost application and agroecological services crops (ASC) cultivation (tailored use of cover crops) as part of crop rotation, and AGROMAN - animal manure and ASC cultivation as part of crop rotation. Monitoring of soil fauna was performed by using pitfall traps and seven taxa were considered: Carabidae, Staphylinidae, Araneae, Opiliones, Isopoda, Myriapoda, and Collembola. Results demonstrated high potential of ASC cultivation as a technique for beneficial soil arthropod conservation in OGH conditions. SUBST system was dominated by Collembola in all crops, while AGROMAN and AGROCOM had more balanced relative abundance of Isopoda, Staphylinidae, and Aranea. Opiliones and Myriapoda were more affected by season, while Carabidae were poorly represented in the whole monitoring period. Despite the fact that all three production systems are in accordance with the European Union regulation on organic farming, findings of this study displayed significant differences among them and confirmed the suitability of soil arthropods as bioindicators in protected systems of organic farming.

Quantification and Controls of Wetland Greenhouse Gas Emissions

Energy Technology Data Exchange (ETDEWEB)

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

2016-05-10

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

Nitrogen supply modulates the effect of changes in drying-rewetting frequency on soil C and N cycling and greenhouse gas exchange.

Science.gov (United States)

Morillas, Lourdes; Durán, Jorge; Rodríguez, Alexandra; Roales, Javier; Gallardo, Antonio; Lovett, Gary M; Groffman, Peter M

2015-10-01

Climate change and atmospheric nitrogen (N) deposition are two of the most important global change drivers. However, the interactions of these drivers have not been well studied. We aimed to assess how the combined effect of soil N additions and more frequent soil drying-rewetting events affects carbon (C) and N cycling, soil:atmosphere greenhouse gas (GHG) exchange, and functional microbial diversity. We manipulated the frequency of soil drying-rewetting events in soils from ambient and N-treated plots in a temperate forest and calculated the Orwin & Wardle Resistance index to compare the response of the different treatments. Increases in drying-rewetting cycles led to reductions in soil NO3- levels, potential net nitrification rate, and soil : atmosphere GHG exchange, and increases in NH4+ and total soil inorganic N levels. N-treated soils were more resistant to changes in the frequency of drying-rewetting cycles, and this resistance was stronger for C- than for N-related variables. Both the long-term N addition and the drying-rewetting treatment altered the functionality of the soil microbial population and its functional diversity. Our results suggest that increasing the frequency of drying-rewetting cycles can affect the ability of soil to cycle C and N and soil : atmosphere GHG exchange and that the response to this increase is modulated by soil N enrichment. © 2015 John Wiley & Sons Ltd.

A microclimate model to investigate greenhouse warming of a sub- Alpine ecosystem

International Nuclear Information System (INIS)

Shen, K.P.

1992-01-01

Increasing concentrations of greenhouse gases in the earth's atmosphere are expected to result in a global warming of several degrees Celsius in the coming decades. This warming will have far-reaching impacts on the biosphere, and while General Circulation Models (GCMs) try to predict the magnitude and scope of the warming, there is little information regarding the potential impacts of greenhouse warming on natural systems. An experiment currently under way in a meadow in the Colorado Rocky Mountains attempts to investigate the many consequences of greenhouse warming for soil ecosystems. A mathematical model of the soil microclimate was developed to simulate the soil temperature and moisture content of the meadow. The model simulates both treatment and control scenarios so as to investigate the potential effects of warming. Results of model simulation studies indicate warmer, drier soils under treatment conditions, with the greatest temperature effects of warming occurring at night. These results could have several implications regarding the dynamics of the ecosystem, and future model studies will investigate these connections

Greenhouse gas mitigation with scarce land

DEFF Research Database (Denmark)

Meyer-Aurich, A; Olesen, Jørgen E; Prochnow, A

2013-01-01

Agricultural lands have been identified to mitigate greenhouse gas (GHG) emissions primarily by production of energy crops and substituting fossil energy resources and through carbon sequestration in soils. Increased fertilizer input resulting in increased yields may reduce the area needed for crop...

Comparison of greenhouse and 32P isotopic laboratory methods for evaluating the agronomic effectiveness of natural and modified rock phosphates in some acid soils of Ghana

International Nuclear Information System (INIS)

Owusu-Bennoah, E.; Zapata, F.; Fardeau, J.C.

2002-01-01

Phosphorus deficiency is one of the major constraints for normal plant growth and crop yields in the acid soils of Ghana and therefore addition of P inputs is required for sustainable crop production. This is often difficult, if not impossible for small-scale farmers due to the high cost of mineral P fertilizers and limited access to fertilizer supplies. Direct application of finely ground phosphate rocks (PRs) and their modified forms have been recommended as alternatives for P fertilization. The direct application of the natural and modified PRs to these acid soils implies the need to predict their agronomic effectiveness of the PRs in the simplest and most cost-effective manner. In this study the classical greenhouse pot experiment was compared to the 32 P isotopic kinetics laboratory method for evaluating the agronomic effectiveness of natural and modified Togo PR in six highly weathered Oxisols from southwest Ghana. In the 32 P isotopic kinetics laboratory experiment the six soil samples were each fertilised at the rate of 50 mg P kg -1 soil in the form of triple superphosphate (TSP), Togo PAPR-50%, and Togo PR, respectively. Controls without P amendment were also included. Isotopic exchange kinetics experiments were carried out on two sets of samples, immediately after P fertilizer additions (without incubation) and after 6 weeks of incubation under wet conditions and at a room temperature of 25 deg C. In the greenhouse pot experiment, P fertilizers in the form of Togo PR, Togo PAPR, Mali PR and TSP were each applied to the six soils at rates equivalent to 0, 30, 60, and 120 kg P ha -1 , respectively. The P fertilizers were mixed with the soils and maize (Zea mays L.) variety Obatanpa was grown for 42 days before harvest. The isotopic kinetics data of the control samples indicated that 5 of the studied soils had very low P fertility status as reflected by their low P concentrations in solution (C P -1 ) and low exchangeable P (E 1 min -1 ). The capacity

Mitigating yield-scaled greenhouse gas emissions through combined application of soil amendments: A comparative study between temperate and subtropical rice paddy soils.

Science.gov (United States)

Ali, Muhammad Aslam; Kim, P J; Inubushi, K

2015-10-01

Effects of different soil amendments were investigated on methane (CH4) and nitrous oxide (N2O) emissions, global warming potential (GWP) and yield scaled GWPs in paddy soils of Republic of Korea, Japan and Bangladesh. The experimental treatments were NPK only, NPK+fly ash, NPK+silicate slag, NPK+phosphogypsum(PG), NPK+blast furnace slag (BFS), NPK+revolving furnace slag (RFS), NPK+silicate slag (50%)+RFS (50%), NPK+biochar, NPK+biochar+Azolla-cyanobacteria, NPK+silicate slag+Azolla-cyanobacteria, NPK+phosphogypsum (PG)+Azolla-cyanobacteria. The maximum decrease in cumulative seasonal CH4 emissions was recorded 29.7% and 32.6% with Azolla-cyanobacteria plus phospho-gypsum amendments in paddy soils of Japan and Bangladesh respectively, followed by 22.4% and 26.8% reduction with silicate slag plus Azolla-cyanobacteria application. Biochar amendments in paddy soils of Japan and Bangladesh decreased seasonal cumulative N2O emissions by 31.8% and 20.0% respectively, followed by 26.3% and 25.0% reduction with biochar plus Azolla-cyanobacteria amendments. Although seasonal cumulative CH4 emissions were significantly increased by 9.5-14.0% with biochar amendments, however, global warming potentials were decreased by 8.0-12.0% with cyanobacterial inoculation plus biochar amendments. The maximum decrease in GWP was calculated 22.0-30.0% with Azolla-cyanobacteria plus silicate slag amendments. The evolution of greenhouse gases per unit grain yield (yield scaled GWP) was highest in the NPK treatment, which was decreased by 43-50% from the silicate slag and phosphogypsum amendments along with Azolla-cyanobacteria inoculated rice planted soils. Conclusively, it is recommended to incorporate Azolla-cyanobacteria with inorganic and organic amendments for reducing GWP and yield scaled GWP from the rice planted paddy soils of temperate and subtropical countries. Copyright © 2015 Elsevier B.V. All rights reserved.

Greenhouse effect of NO{sub x}

Energy Technology Data Exchange (ETDEWEB)

Lammel, G; Grassl, H [Max-Planck-Institut fuer Meteorologie, Hamburg (Germany)

1995-07-01

Through various processes the nitrogen oxides (NO{sub x}) interact with trace gases in the troposphere and stratosphere which do absorb in the spectral range relevant to the greenhouse effect (infrared wavelengths). The net effect is an enhancement of the greenhouse effect. The catalytic role of NO{sub x} in the production of tropospheric ozone provides the most prominent contribution. The global waming potential is estimated as GWP (NO{sub x}) = 30-33 and 7-10 for the respective time horizons of 20 and 100 years, and is thereby comparable to that of methane. NO{sub x} emissions in rural areas of anthropogenically influenced regions, or those in the vicinity of the tropopause caused by air traffic, cause the greenhouse effectivity to be substantially more intense. We estimate an additional 5-23% for Germany`s contribution to the anthropogenic greenhouse effect as a result of the indirect greenhouse effects stemming from NO{sub x}. Furthermore, a small and still inaccurately defined amount of the deposited NO{sub x} which has primarily been converted into nitrates is again released from the soil into the atmosphere in the form of the long-lived greenhouse gas nitrous oxide (N{sub i}O). Thus, anthropogenically induced NO{sub x} emissions contribute to enhanced greenhouse effect and to stratospheric ozone depletion in the time scale of more than a century. (orig.)

Greenhouse irrigation control system design based on ZigBee and fuzzy PID technology

Science.gov (United States)

Zhou, Bing; Yang, Qiliang; Liu, Kenan; Li, Peiqing; Zhang, Jing; Wang, Qijian

In order to achieve the water demand information accurately detect of the greenhouse crop and its precision irrigation automatic control, this article has designed a set of the irrigated control system based on ZigBee and fuzzy PID technology, which composed by the soil water potential sensor, CC2530F256 wireless microprocessor, IAR Embedded Workbench software development platform. And the time of Irrigation as the output .while the amount of soil water potential and crop growth cycle as the input. The article depended on Greenhouse-grown Jatropha to verify the object, the results show that the system can irrigate timely and appropriately according to the soil water potential and water demend of the different stages of Jatropha growth , which basically meet the design requirements. Therefore, the system has broad application prospects in the amount of greenhouse crop of fine control irrigation.

Effect of pest controlling neem and mata-raton leaf extracts on greenhouse gas emissions from urea-amended soil cultivated with beans: A greenhouse experiment

International Nuclear Information System (INIS)

Mendez-Bautista, Joaquin; Fernandez-Luqueno, Fabian; Lopez-Valdez, Fernando; Mendoza-Cristino, Reyna; Montes-Molina, Joaquin A.; Gutierrez-Miceli, Federico A.; Dendooven, L.

2010-01-01

In a previous laboratory experiment, extracts of neem (Azadirachta indica A. Juss.) and Gliricidia sepium Jacquin, locally known as mata-raton, used to control pests on crops, inhibited emissions of CO 2 from a urea-amended soil, but not nitrification and N 2 O emissions. We investigated if these extracts when applied to beans (Phaseolus vulgaris L.) affected their development, soil characteristics and emissions of carbon dioxide (CO 2 ) and nitrous oxide (N 2 O) in a greenhouse environment. Untreated beans and beans planted with lambda-cyhalothrin, a commercial insecticide, served as controls. After 117 days, shoots of plants cultivated in soil amended with urea or treated with lambda-cyhalothrin, or extracts of neem or G. sepium were significantly higher than when cultivated in the unamended soil, while the roots were significantly longer when plants were amended with urea or treated with leaf extracts of neem or G. sepium than when treated with lambda-cyhalothrin. The number of pods, fresh and dry pod weight and seed yield was significantly higher when bean plants were treated with leaf extracts of neem or G. sepium treatments than when left untreated and unfertilized. The number of seeds was similar for the different treatments. The number of nodules was lower in plants fertilized with urea, treated with leaf extracts of neem or G. sepium, or with lambda-cyhalothrin compared to the unfertilized plants. The concentrations of NH 4 + , NO 2 - and NO 3 - decreased significantly over time with the lowest concentrations generally found at harvest. Treatment had no significant effect on the concentrations of NH 4 + and NO 2 - , but the concentration of NO 3 - was significantly lower in the unfertilized soil compared to the other treatments. It was found that applying extracts of neem or G. sepium leaves to beans favored their development when compared to untreated plants, but had no significant effect on nitrification in soil.

Effect of pest controlling neem and mata-raton leaf extracts on greenhouse gas emissions from urea-amended soil cultivated with beans: A greenhouse experiment

Energy Technology Data Exchange (ETDEWEB)

Mendez-Bautista, Joaquin [Laboratory of Soil Ecology, Cinvestav, Mexico D.F. (Mexico); Fernandez-Luqueno, Fabian [Laboratory of Soil Ecology, Cinvestav, Mexico D.F. (Mexico); Department of Electromechanics, Renewable Energy Engineering, UTTulancingo, Hidalgo (Mexico); Lopez-Valdez, Fernando [Laboratory of Soil Ecology, Cinvestav, Mexico D.F. (Mexico); C.I.B.A.-I.P.N., Tepetitla de Lardizabal, Tlaxcala (Mexico); Mendoza-Cristino, Reyna [Laboratory of Soil Ecology, Cinvestav, Mexico D.F. (Mexico); Montes-Molina, Joaquin A.; Gutierrez-Miceli, Federico A. [Laboratorio de Biotecnologia Vegetal, Instituto Tecnologico de Tuxtla-Gutierrez, Tuxtla-Gutierrez (Mexico); Dendooven, L., E-mail: dendoove@cinvestav.mx [Laboratory of Soil Ecology, Cinvestav, Mexico D.F. (Mexico)

2010-10-01

In a previous laboratory experiment, extracts of neem (Azadirachta indica A. Juss.) and Gliricidia sepium Jacquin, locally known as mata-raton, used to control pests on crops, inhibited emissions of CO{sub 2} from a urea-amended soil, but not nitrification and N{sub 2}O emissions. We investigated if these extracts when applied to beans (Phaseolus vulgaris L.) affected their development, soil characteristics and emissions of carbon dioxide (CO{sub 2}) and nitrous oxide (N{sub 2}O) in a greenhouse environment. Untreated beans and beans planted with lambda-cyhalothrin, a commercial insecticide, served as controls. After 117 days, shoots of plants cultivated in soil amended with urea or treated with lambda-cyhalothrin, or extracts of neem or G. sepium were significantly higher than when cultivated in the unamended soil, while the roots were significantly longer when plants were amended with urea or treated with leaf extracts of neem or G. sepium than when treated with lambda-cyhalothrin. The number of pods, fresh and dry pod weight and seed yield was significantly higher when bean plants were treated with leaf extracts of neem or G. sepium treatments than when left untreated and unfertilized. The number of seeds was similar for the different treatments. The number of nodules was lower in plants fertilized with urea, treated with leaf extracts of neem or G. sepium, or with lambda-cyhalothrin compared to the unfertilized plants. The concentrations of NH{sub 4}{sup +}, NO{sub 2}{sup -} and NO{sub 3}{sup -} decreased significantly over time with the lowest concentrations generally found at harvest. Treatment had no significant effect on the concentrations of NH{sub 4}{sup +} and NO{sub 2}{sup -}, but the concentration of NO{sub 3}{sup -} was significantly lower in the unfertilized soil compared to the other treatments. It was found that applying extracts of neem or G. sepium leaves to beans favored their development when compared to untreated plants, but had no significant

Bryophyte-dominated biological soil crusts mitigate soil erosion in an early successional Chinese subtropical forest

Directory of Open Access Journals (Sweden)

S. Seitz

2017-12-01

Full Text Available This study investigated the development of biological soil crusts (biocrusts in an early successional subtropical forest plantation and their impact on soil erosion. Within a biodiversity and ecosystem functioning experiment in southeast China (biodiversity and ecosystem functioning (BEF China, the effect of these biocrusts on sediment delivery and runoff was assessed within micro-scale runoff plots under natural rainfall, and biocrust cover was surveyed over a 5-year period. Results showed that biocrusts occurred widely in the experimental forest ecosystem and developed from initial light cyanobacteria- and algae-dominated crusts to later-stage bryophyte-dominated crusts within only 3 years. Biocrust cover was still increasing after 6 years of tree growth. Within later-stage crusts, 25 bryophyte species were determined. Surrounding vegetation cover and terrain attributes significantly influenced the development of biocrusts. Besides high crown cover and leaf area index, the development of biocrusts was favoured by low slope gradients, slope orientations towards the incident sunlight and the altitude of the research plots. Measurements showed that bryophyte-dominated biocrusts strongly decreased soil erosion, being more effective than abiotic soil surface cover. Hence, their significant role in mitigating sediment delivery and runoff generation in mesic forest environments and their ability to quickly colonise soil surfaces after disturbance are of particular interest for soil erosion control in early-stage forest plantations.

Bryophyte-dominated biological soil crusts mitigate soil erosion in an early successional Chinese subtropical forest

Science.gov (United States)

Seitz, Steffen; Nebel, Martin; Goebes, Philipp; Käppeler, Kathrin; Schmidt, Karsten; Shi, Xuezheng; Song, Zhengshan; Webber, Carla L.; Weber, Bettina; Scholten, Thomas

2017-12-01

This study investigated the development of biological soil crusts (biocrusts) in an early successional subtropical forest plantation and their impact on soil erosion. Within a biodiversity and ecosystem functioning experiment in southeast China (biodiversity and ecosystem functioning (BEF) China), the effect of these biocrusts on sediment delivery and runoff was assessed within micro-scale runoff plots under natural rainfall, and biocrust cover was surveyed over a 5-year period. Results showed that biocrusts occurred widely in the experimental forest ecosystem and developed from initial light cyanobacteria- and algae-dominated crusts to later-stage bryophyte-dominated crusts within only 3 years. Biocrust cover was still increasing after 6 years of tree growth. Within later-stage crusts, 25 bryophyte species were determined. Surrounding vegetation cover and terrain attributes significantly influenced the development of biocrusts. Besides high crown cover and leaf area index, the development of biocrusts was favoured by low slope gradients, slope orientations towards the incident sunlight and the altitude of the research plots. Measurements showed that bryophyte-dominated biocrusts strongly decreased soil erosion, being more effective than abiotic soil surface cover. Hence, their significant role in mitigating sediment delivery and runoff generation in mesic forest environments and their ability to quickly colonise soil surfaces after disturbance are of particular interest for soil erosion control in early-stage forest plantations.

Effects of land use on greenhouse gas fluxes and soil properties of wetland catchments in the Prairie Pothole Region of North America

Energy Technology Data Exchange (ETDEWEB)

Tangen, Brian A., E-mail: btangen@usgs.gov; Finocchiaro, Raymond G., E-mail: rfinocchiaro@usgs.gov; Gleason, Robert A., E-mail: rgleason@usgs.gov

2015-11-15

Wetland restoration has been suggested as policy goal with multiple environmental benefits including enhancement of atmospheric carbon sequestration. However, there are concerns that increased methane (CH{sub 4}) emissions associated with restoration may outweigh potential benefits. A comprehensive, 4-year study of 119 wetland catchments was conducted in the Prairie Pothole Region of the north-central U.S. to assess the effects of land use on greenhouse gas (GHG) fluxes and soil properties. Results showed that the effects of land use on GHG fluxes and abiotic soil properties differed with respect to catchment zone (upland, wetland), wetland classification, geographic location, and year. Mean CH{sub 4} fluxes from the uplands were predictably low (< 0.02 g CH{sub 4} m{sup −2} day{sup −1}), while wetland zone CH{sub 4} fluxes were much greater (< 0.001–3.9 g CH{sub 4} m{sup −2} day{sup −1}). Mean cumulative seasonal CH{sub 4} fluxes ranged from roughly 0–650 g CH{sub 4} m{sup −2}, with an overall mean of approximately 160 g CH{sub 4} m{sup −2}. These maximum cumulative CH{sub 4} fluxes were nearly 3 times as high as previously reported in North America. The overall magnitude and variability of N{sub 2}O fluxes from this study (< 0.0001–0.0023 g N{sub 2}O m{sup −2} day{sup −1}) were comparable to previously reported values. Results suggest that soil organic carbon is lost when relatively undisturbed catchments are converted for agriculture, and that when non-drained cropland catchments are restored, CH{sub 4} fluxes generally are not different than the pre-restoration baseline. Conversely, when drained cropland catchments are restored, CH{sub 4} fluxes are noticeably higher. Consequently, it is important to consider the type of wetland restoration (drained, non-drained) when assessing restoration benefits. Results also suggest that elevated N{sub 2}O fluxes from cropland catchments likely would be reduced through restoration. The overall

A Global Meta-Analysis on the Impact of Management Practices on Net Global Warming Potential and Greenhouse Gas Intensity from Cropland Soils

Science.gov (United States)

Sainju, Upendra M.

2016-01-01

Management practices, such as tillage, crop rotation, and N fertilization, may affect net global warming potential (GWP) and greenhouse gas intensity (GHGI), but their global impact on cropland soils under different soil and climatic conditions need further evaluation. Available global data from 57 experiments and 225 treatments were evaluated for individual and combined effects of tillage, cropping systems, and N fertilization rates on GWP and GHGI which accounted for CO2 equivalents from N2O and CH4 emissions with or without equivalents from soil C sequestration rate (ΔSOC), farm operations, and N fertilization. The GWP and GHGI were 66 to 71% lower with no-till than conventional till and 168 to 215% lower with perennial than annual cropping systems, but 41 to 46% greater with crop rotation than monocroppping. With no-till vs. conventional till, GWP and GHGI were 2.6- to 7.4-fold lower when partial than full accounting of all sources and sinks of greenhouse gases (GHGs) were considered. With 100 kg N ha-1, GWP and GHGI were 3.2 to 11.4 times greater with partial than full accounting. Both GWP and GHGI increased curvilinearly with increased N fertilization rate. Net GWP and GHGI were 70 to 87% lower in the improved combined management that included no-till, crop rotation/perennial crop, and reduced N rate than the traditional combined management that included conventional till, monocopping/annual crop, and recommended N rate. An alternative soil respiration method, which replaces ΔSOC by soil respiration and crop residue returned to soil in the previous year, similarly reduced GWP and GHGI by 133 to 158% in the improved vs. the traditional combined management. Changes in GWP and GHGI due to improved vs. traditional management varied with the duration of the experiment and inclusion of soil and climatic factors in multiple linear regressions improved their relationships. Improved management practices reduced GWP and GHGI compared with traditional management

A Global Meta-Analysis on the Impact of Management Practices on Net Global Warming Potential and Greenhouse Gas Intensity from Cropland Soils.

Science.gov (United States)

Sainju, Upendra M

2016-01-01

Management practices, such as tillage, crop rotation, and N fertilization, may affect net global warming potential (GWP) and greenhouse gas intensity (GHGI), but their global impact on cropland soils under different soil and climatic conditions need further evaluation. Available global data from 57 experiments and 225 treatments were evaluated for individual and combined effects of tillage, cropping systems, and N fertilization rates on GWP and GHGI which accounted for CO2 equivalents from N2O and CH4 emissions with or without equivalents from soil C sequestration rate (ΔSOC), farm operations, and N fertilization. The GWP and GHGI were 66 to 71% lower with no-till than conventional till and 168 to 215% lower with perennial than annual cropping systems, but 41 to 46% greater with crop rotation than monocroppping. With no-till vs. conventional till, GWP and GHGI were 2.6- to 7.4-fold lower when partial than full accounting of all sources and sinks of greenhouse gases (GHGs) were considered. With 100 kg N ha-1, GWP and GHGI were 3.2 to 11.4 times greater with partial than full accounting. Both GWP and GHGI increased curvilinearly with increased N fertilization rate. Net GWP and GHGI were 70 to 87% lower in the improved combined management that included no-till, crop rotation/perennial crop, and reduced N rate than the traditional combined management that included conventional till, monocopping/annual crop, and recommended N rate. An alternative soil respiration method, which replaces ΔSOC by soil respiration and crop residue returned to soil in the previous year, similarly reduced GWP and GHGI by 133 to 158% in the improved vs. the traditional combined management. Changes in GWP and GHGI due to improved vs. traditional management varied with the duration of the experiment and inclusion of soil and climatic factors in multiple linear regressions improved their relationships. Improved management practices reduced GWP and GHGI compared with traditional management

The impact of soil amendments on greenhouse gas emissions: a comprehensive life cycle assessment approach

Science.gov (United States)

DeLonge, M. S.; Ryals, R.; Silver, W. L.

2011-12-01

Soil amendments, such as compost and manure, can be applied to grasslands to improve soil conditions and enhance aboveground net primary productivity. Applying such amendments can also lead to soil carbon (C) sequestration and, when materials are diverted from waste streams (e.g., landfills, manure lagoons), can offset greenhouse gas (GHG) emissions. However, amendment production and application is also associated with GHG emissions, and the net impact of these amendments remains unclear. To investigate the potential for soil amendments to reduce net GHG emissions, we developed a comprehensive, field-scale life cycle assessment (LCA) model. The LCA includes GHG (i.e., CO2, CH4, N2O) emissions of soil amendment production, application, and ecosystem response. Emissions avoided by diverting materials from landfills or manure management systems are also considered. We developed the model using field observations from grazed annual grassland in northern California (e.g., soil C; above- and belowground net primary productivity; C:N ratios; trace gas emissions from soils, manure piles, and composting), CENTURY model simulations (e.g., long-term soil C and trace gas emissions from soils under various land management strategies), and literature values (e.g., GHG emissions from transportation, inorganic fertilizer production, composting, and enteric fermentation). The LCA quantifies and contrasts the potential net GHG impacts of applying compost, manure, and commercial inorganic fertilizer to grazing lands. To estimate the LCA uncertainty, sensitivity tests were performed on the most widely ranging or highly uncertain parameters (e.g., compost materials, landfill emissions, manure management system emissions). Finally, our results are scaled-up to assess the feasibility and potential impacts of large-scale adoption of soil amendment application as a land-management strategy in California. Our base case results indicate that C sinks and emissions offsets associated with

Temperature response of denitrification rate and greenhouse gas production in agricultural river marginal wetland soils.

Science.gov (United States)

Bonnett, S A F; Blackwell, M S A; Leah, R; Cook, V; O'Connor, M; Maltby, E

2013-05-01

Soils are predicted to exhibit significant feedback to global warming via the temperature response of greenhouse gas (GHG) production. However, the temperature response of hydromorphic wetland soils is complicated by confounding factors such as oxygen (O2 ), nitrate (NO3-) and soil carbon (C). We examined the effect of a temperature gradient (2-25 °C) on denitrification rates and net nitrous oxide (N2 O), methane (CH4 ) production and heterotrophic respiration in mineral (Eutric cambisol and Fluvisol) and organic (Histosol) soil types in a river marginal landscape of the Tamar catchment, Devon, UK, under non-flooded and flooded with enriched NO3- conditions. It was hypothesized that the temperature response is dependent on interactions with NO3--enriched flooding, and the physicochemical conditions of these soil types. Denitrification rate (mean, 746 ± 97.3 μg m(-2)  h(-1) ), net N2 O production (mean, 180 ± 26.6 μg m(-2)  h(-1) ) and net CH4 production (mean, 1065 ± 183 μg m(-2)  h(-1) ) were highest in the organic Histosol, with higher organic matter, ammonium and moisture, and lower NO3- concentrations. Heterotrophic respiration (mean, 127 ± 4.6 mg m(-2)  h(-1) ) was not significantly different between soil types and dominated total GHG (CO2 eq) production in all soil types. Generally, the temperature responses of denitrification rate and net N2 O production were exponential, whilst net CH4 production was unresponsive, possibly due to substrate limitation, and heterotrophic respiration was exponential but limited in summer at higher temperatures. Flooding with NO3- increased denitrification rate, net N2 O production and heterotrophic respiration, but a reduction in net CH4 production suggests inhibition of methanogenesis by NO3- or N2 O produced from denitrification. Implications for management and policy are that warming and flood events may promote microbial interactions in soil between distinct microbial communities and increase

Greenhouse gases emission from soils under major crops in Northwest India

Energy Technology Data Exchange (ETDEWEB)

Jain, N., E-mail: nivetajain@gmail.com [Centre for Environment Science and Climate Resilient Agriculture, ICAR-Indian Agricultural Research Institute, New Delhi 110 012 (India); Arora, P.; Tomer, R.; Mishra, Shashi Vind; Bhatia, A.; Pathak, H. [Centre for Environment Science and Climate Resilient Agriculture, ICAR-Indian Agricultural Research Institute, New Delhi 110 012 (India); Chakraborty, D. [Division of Agricultural Physics, ICAR-Indian Agricultural Research Institute, New Delhi 110 012 (India); Kumar, Vinod; Dubey, D.S.; Harit, R.C.; Singh, J.P. [Centre for Environment Science and Climate Resilient Agriculture, ICAR-Indian Agricultural Research Institute, New Delhi 110 012 (India)

2016-01-15

Quantification of greenhouse gases (GHGs) emissions from agriculture is necessary to prepare the national inventories and to develop the mitigation strategies. Field experiments were conducted during 2008–2010 at the experimental farm of the Indian Agricultural Research Institute, New Delhi, India to quantify nitrous oxide (N{sub 2}O), methane (CH{sub 4}), and carbon dioxide (CO{sub 2}) emissions from soils under cereals, pulses, millets, and oilseed crops. Total cumulative N{sub 2}O emissions were significantly different (P > 0.05) among the crop types. Emission of N{sub 2}O as percentage of applied N was the highest in pulses (0.67%) followed by oilseeds (0.55%), millets (0.43%) and cereals (0.40%). The emission increased with increasing rate of N application (r{sup 2} = 0.74, P < 0.05). The cumulative flux of CH{sub 4} from the rice crop was 28.64 ± 4.40 kg ha{sup −1}, while the mean seasonal integrated flux of CO{sub 2} from soils ranged from 3058 ± 236 to 3616 ± 157 kg CO{sub 2} ha{sup −1} under different crops. The global warming potential (GWP) of crops varied between 3053 kg CO{sub 2} eq. ha{sup −1} (pigeon pea) and 3968 kg CO{sub 2} eq. ha{sup −1} (wheat). The carbon equivalent emission (CEE) was least in pigeon pea (833 kg C ha{sup −1}) and largest in wheat (1042 kg C ha{sup −1}). The GWP per unit of economic yield was the highest in pulses and the lowest in cereal crops. The uncertainties in emission values varied from 4.6 to 22.0%. These emission values will be useful in updating the GHGs emission inventory of Indian agriculture. - Highlights: • Nitrous oxide, methane and carbon dioxide emission were quantified from soils under cereals, millets, oilseeds, and pulses in northwest India. • The emission of nitrous oxide ranged from 0.57–1.3 kg ha{sup −1}, methane from 27.78–29.50 kg ha{sup −1} and carbon dioxide from 2377–3910 kg ha{sup −1}. • Emission of nitrous oxide as percent of applied N was highest in pulses (0

Greenhouse gases emission from soils under major crops in Northwest India

International Nuclear Information System (INIS)

Jain, N.; Arora, P.; Tomer, R.; Mishra, Shashi Vind; Bhatia, A.; Pathak, H.; Chakraborty, D.; Kumar, Vinod; Dubey, D.S.; Harit, R.C.; Singh, J.P.

2016-01-01

Quantification of greenhouse gases (GHGs) emissions from agriculture is necessary to prepare the national inventories and to develop the mitigation strategies. Field experiments were conducted during 2008–2010 at the experimental farm of the Indian Agricultural Research Institute, New Delhi, India to quantify nitrous oxide (N 2 O), methane (CH 4 ), and carbon dioxide (CO 2 ) emissions from soils under cereals, pulses, millets, and oilseed crops. Total cumulative N 2 O emissions were significantly different (P > 0.05) among the crop types. Emission of N 2 O as percentage of applied N was the highest in pulses (0.67%) followed by oilseeds (0.55%), millets (0.43%) and cereals (0.40%). The emission increased with increasing rate of N application (r 2 = 0.74, P < 0.05). The cumulative flux of CH 4 from the rice crop was 28.64 ± 4.40 kg ha −1 , while the mean seasonal integrated flux of CO 2 from soils ranged from 3058 ± 236 to 3616 ± 157 kg CO 2 ha −1 under different crops. The global warming potential (GWP) of crops varied between 3053 kg CO 2 eq. ha −1 (pigeon pea) and 3968 kg CO 2 eq. ha −1 (wheat). The carbon equivalent emission (CEE) was least in pigeon pea (833 kg C ha −1 ) and largest in wheat (1042 kg C ha −1 ). The GWP per unit of economic yield was the highest in pulses and the lowest in cereal crops. The uncertainties in emission values varied from 4.6 to 22.0%. These emission values will be useful in updating the GHGs emission inventory of Indian agriculture. - Highlights: • Nitrous oxide, methane and carbon dioxide emission were quantified from soils under cereals, millets, oilseeds, and pulses in northwest India. • The emission of nitrous oxide ranged from 0.57–1.3 kg ha −1 , methane from 27.78–29.50 kg ha −1 and carbon dioxide from 2377–3910 kg ha −1 . • Emission of nitrous oxide as percent of applied N was highest in pulses (0.67%) followed by oilseeds (0.55%). • Global warming potential (GWP) of soils under different

Soil properties, greenhouse gas emissions and crop yield under compost, biochar and co-composted biochar in two tropical agronomic systems.

Science.gov (United States)

Bass, Adrian M; Bird, Michael I; Kay, Gavin; Muirhead, Brian

2016-04-15

The addition of organic amendments to agricultural soils has the potential to increase crop yields, reduce dependence on inorganic fertilizers and improve soil condition and resilience. We evaluated the effect of biochar (B), compost (C) and co-composted biochar (COMBI) on the soil properties, crop yield and greenhouse gas emissions from a banana and a papaya plantation in tropical Australia in the first harvest cycle. Biochar, compost and COMBI organic amendments improved soil properties, including significant increases in soil water content, CEC, K, Ca, NO3, NH4 and soil carbon content. However, increases in soil nutrient content and improvements in physical properties did not translate to improved fruit yield. Counter to our expectations, banana crop yield (weight per bunch) was reduced by 18%, 12% and 24% by B, C and COMBI additions respectively, and no significant effect was observed on the papaya crop yield. Soil efflux of CO2 was elevated by addition of C and COMBI amendments, likely due to an increase in labile carbon for microbial processing. Our data indicate a reduction in N2O flux in treatments containing biochar. The application of B, C and COMBI amendments had a generally positive effect on soil properties, but this did not translate into a crop productivity increase in this study. The benefits to soil nutrient content, soil carbon storage and N2O emission reduction need to be carefully weighed against potentially deleterious effects on crop yield, at least in the short-term. Copyright © 2016 Elsevier B.V. All rights reserved.

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

DEFF Research Database (Denmark)

Hu, Wenyou; Huang, Biao; Tian, Kang

2017-01-01

Recently, greenhouse vegetable production (GVP) has grown rapidly and counts a large proportion of vegetable production in China. In this study, the accumulation, health risk and threshold values of selected heavy metals were evaluated systematically. A total of 120 paired soil and vegetable...... relatively high concentrations and transfer factors of heavy metals. The accumulation of heavy metals in soils was affected by soil pH and soil organic matter. The calculated hazard quotients (HQ) of the heavy metals by vegetable consumption decreased in the order of leafy > rootstalk > fruit vegetables...... with hazard index (HI) values of 0.61, 0.33 and 0.26, respectively. The HI values were all below 1, which indicates that there is a low risk of greenhouse vegetable consumption. Soil threshold values (STVs) of heavy metals in GVP system were established according to the health risk assessment. The relatively...

Edaphic factors controlling summer (rainy season) greenhouse gas emissions (CO{sub 2} and CH{sub 4}) from semiarid mangrove soils (NE-Brazil)

Energy Technology Data Exchange (ETDEWEB)

Nóbrega, Gabriel N. [Departamento de Ciência do Solo, Escola Superior de Agricultura Luiz de Queiroz, ESALQ/USP, Av.Pádua Dias 11, Piracicaba, São Paulo 13.418-260 (Brazil); Ferreira, Tiago O., E-mail: toferreira@usp.br [Departamento de Ciência do Solo, Escola Superior de Agricultura Luiz de Queiroz, ESALQ/USP, Av.Pádua Dias 11, Piracicaba, São Paulo 13.418-260 (Brazil); Siqueira Neto, M. [Laboratório de Biogeoquímica Ambiental, Centro de Energia Nuclear na Agricultura, CENA/USP, Av. Centenário 303, Piracicaba, São Paulo 13.400-970 (Brazil); Queiroz, Hermano M.; Artur, Adriana G. [Departamento de Ciências do Solo, Universidade Federal do Ceará, UFC, Av. Mister Hull 2977, Campus do Pici, Fortaleza, Ceará 60.440-554 (Brazil); Mendonça, Eduardo De S. [Departamento de Produção Vegetal, Universidade Federal do Espírito Santo, UFES, Alto Universitário s/n, Alegre, Espírito Santo 29.500-000 (Brazil); Silva, Ebenezer De O. [Empresa Brasileira de Pesquisa Agropecuária, Centro Nacional de Pesquisa de Agroindústria Tropical, Pós Colheita, Dra. Sara Mesquita Street, 2270, Planalto Pici, Fortaleza, Ceará 60.511-110 (Brazil); and others

2016-01-15

The soil attributes controlling the CO{sub 2}, and CH{sub 4} emissions were assessed in semiarid mangrove soils (NE-Brazil) under different anthropogenic activities. Soil samples were collected from different mangroves under different anthropogenic impacts, e.g., shrimp farming (Jaguaribe River); urban wastes (Cocó River) and a control site (Timonha River). The sites were characterized according to the sand content; physicochemical parameters (Eh and pH); total organic C; soil C stock (SCS) and equivalent SCS (SCS{sub EQV}); total P and N; dissolved organic C (DOC); and the degree of pyritization (DOP). The CO{sub 2} and CH{sub 4} fluxes from the soils were assessed using static closed chambers. Higher DOC and SCS and the lowest DOP promote greater CO{sub 2} emission. The CH{sub 4} flux was only observed at Jaguaribe which presented higher DOP, compared to that found in mangroves from humid tropical climates. Semiarid mangrove soils cannot be characterized as important greenhouse gas sources, compared to humid tropical mangroves. - Highlights: • GHG emission was associated with different soil characteristics. • Highest CO{sub 2} emissions were found in mangroves with larger dissolved C and lower DOP. • Less CH{sub 4} flux was due to low DOP in semiarid mangrove soils.

Accumulation status, sources and phytoavailability of metals in greenhouse vegetable production systems in Beijing, China.

Science.gov (United States)

Xu, Li; Lu, Anxiang; Wang, Jihua; Ma, Zhihong; Pan, Ligang; Feng, Xiaoyuan; Luan, Yunxia

2015-12-01

The accumulation status, sources and phytoavailability of selected metals in greenhouse vegetable production systems in peri-urban areas of Beijing were investigated. The mean concentrations of As, Cd, Cr, Hg and Pb in greenhouse soils were 8.44, 0.25, 69.0, 0.09 and 22.0 mg kg(-1), dw, respectively. According to principal component analysis, As, Cd, Cr and Hg are mainly from anthropogenic source, but Pb is likely from natural source. Metal concentrations in all vegetable samples were decreased in the order of Cr>As>Pb>Cd>Hg. Compared with root and fruit vegetables, leaf vegetables had relatively high concentrations and transfer factors of heavy metals, except for Cd. By including soil pH, OM and greenhouse soil metals, 10 empirical models were derived using stepwise multiple linear regression analysis to predict heavy metal concentrations in the edible parts of different vegetables. Among the different vegetable groups, the highest intakes of metals occurred through consumption of leaf vegetables for the two age groups, except for Cd. The HI value of the studied metals were all below 1, indicating that consumption of vegetables grown in greenhouse soils was of low risk to consumers in our study area. Copyright © 2015 Elsevier Inc. All rights reserved.

Achievements and opportunities from ESF Research Networking Programme: Natural molecular structures as drivers and tracers of terrestrial C fluxes, and COST Action 639: Greenhouse gas budget of soils under changing climate and land use

Science.gov (United States)

Boeckx, P.; Rasse, D.; Jandl, R.

2009-04-01

One of the activities of the European Science Foundation (ESF, www.esf.org) is developing European scale Research Networking Programmes (RNPs). RNPs lay the foundation for nationally funded research groups to address major scientific and research infrastructure issues, in order to advance the frontiers of existing science. MOLTER (www.esf.org/molter or www.molter.no) is such an RNP. MOLTER stands for "Natural molecular structures as drivers and tracers of terrestrial C fluxes" aims at stimulating the use of isotopic and organic chemistry to study carbon stabilization and biogeochemistry in terrestrial ecosystems and soils in particular. The understanding of the formation, stabilization and decomposition of complex organic compounds in the environment is currently being revolutionized by advanced techniques in identification, quantification, and origin tracing of functional groups and individual molecules. MOLTER focuses on five major research themes: - Molecular composition and turnover time of soil organic matter; - Plant molecular structures as drivers of C stabilisation in soils; - Fire transformations of plant and soil molecular structures - Molecular markers in soils; - Dissolved organic molecules in soils: origin, functionality and transport. These research themes are covered via the following activities: - Organisation of international conferences; - Organisation of specific topical workshops; - Organisation of summer schools for PhD students; - Short- and long-term exchange grants for scientists. MOLTER is supported by research funding or performing agencies from Austria, Belgium, France, Germany, the Netherlands, Norway, Romania, Spain, Sweden, Switzerland and the United Kingdom. The ESF is also the implementing agency of COST (European Cooperation in Science and Technology, www.cost.esf.org), one of the longest-running European instruments supporting cooperation among scientists and researchers across Europe. COST Action 639 "Greenhouse gas budget of

Agriculture and the greenhouse gas emissions: A literature review

International Nuclear Information System (INIS)

Kulmala, A.; Esala, M.

2000-01-01

Agriculture contributes to the greenhouse effect by increasing carbon dioxide, nitrous oxide and methane emissions. This literature review examines agricultural sources and sinks of greenhouse gases as well as factors affecting emissions. Options for mitigating emissions are presented as well the results of greenhouse gas emission measurements on Finnish agricultural soils. In addition, some basic information is given about Finnish agriculture, and the estimation of emissions using the IPCC Guidelines is described. Carbon dioxide sources include decomposition of soil organic matter, combustion and liming. The agricultural sector can mitigate CO 2 emissions by increasing carbon stocks in soils and vegetation, reducing fossil fuel consumption, and increasing the production of bioenergy. There is little opportunity to decrease the amount of liming in Finland. The main nitrous oxide sources are nitrification and denitrification. N 2 O emissions can be reduced by enhancing plants' ability to compete for soil nitrogen and by keeping the rate of emission processes as low and the duration of emissions as short as possible. Special attention should be paid to manure management because manure contains abundant nitrogen that can be lost as N 2 O. Improvements in the protein feeding of livestock could also reduce potential N 2 O emissions from manure. Methane is emitted, for example, in the course of enteric fermentation and the anaerobic decomposition of organic matter in manure. The emission of CH 4 from soils depends on the relative amounts of methane production and consumption. Cattle with high productivity emit less methane per unit of milk or meat than do animals with low productivity. The number of breeding animals could be reduced by improving animal reproduction efficiency. Methane emitted from manure should be utilized as an energy source, or the formation of it should be prevented by keeping manure under aerobic conditions

Dissipation rate of thiacloprid and its control effect against Bemisia tabaci in greenhouse tomato after soil application.

Science.gov (United States)

Dong, Sa; Qiao, Kang; Wang, Hongyan; Zhu, Yukun; Xia, Xiaoming; Wang, Kaiyun

2014-08-01

Thiacloprid is a chloronicotinyl insecticide that is quite effective against sucking insects. In this study, when thiacloprid was applied at two different rates (normal rate 15 kg ha(-1) , double rate 30 kg ha(-1) ), the systemic distribution and residue of thiacloprid as well as its control effect against whitefly (Bemisia tabaci) were investigated in greenhouse tomato after soil application. The results showed that thiacloprid was present in the tomato leaves until day 25, and then its amount was less than 0.005 mg kg(-1) and could not be detected. Thiacloprid residue in the tomato stems basically remained at a stable low level throughout the experimental period. Thiacloprid in soil had half-lives of 11.8 and 12.5 days for the normal treatment and the double treatment respectively. The control efficiency of whiteflies was about 90% from day 1 to day 10. This was followed by a slow decline, but efficiency was still higher than 50% until day 21. In addition, no significant differences were noted in the control effect of thiacloprid on whiteflies between the two different rates. Soil application of thiacloprid at the normal rate can effectively control whiteflies, with high efficiency and long persistence. © 2013 Society of Chemical Industry.

Greenhouse gas fluxes from agricultural soils under organic and non-organic management — A global meta-analysis

International Nuclear Information System (INIS)

Skinner, Colin; Gattinger, Andreas; Muller, Adrian; Mäder, Paul; Fließbach, Andreas; Stolze, Matthias; Ruser, Reiner; Niggli, Urs

2014-01-01

It is anticipated that organic farming systems provide benefits concerning soil conservation and climate protection. A literature search on measured soil-derived greenhouse gas (GHG) (nitrous oxide and methane) fluxes under organic and non-organic management from farming system comparisons was conducted and followed by a meta-analysis. Up to date only 19 studies based on field measurements could be retrieved. Based on 12 studies that cover annual measurements, it appeared with a high significance that area-scaled nitrous oxide emissions from organically managed soils are 492 ± 160 kg CO 2 eq. ha −1 a −1 lower than from non-organically managed soils. For arable soils the difference amounts to 497 ± 162 kg CO 2 eq. ha −1 a −1 . However, yield-scaled nitrous oxide emissions are higher by 41 ± 34 kg CO 2 eq. t −1 DM under organic management (arable and use). To equalize this mean difference in yield-scaled nitrous oxide emissions between both farming systems, the yield gap has to be less than 17%. Emissions from conventionally managed soils seemed to be influenced mainly by total N inputs, whereas for organically managed soils other variables such as soil characteristics seemed to be more important. This can be explained by the higher bioavailability of the synthetic N fertilisers in non-organic farming systems while the necessary mineralisation of the N sources under organic management leads to lower and retarded availability. Furthermore, a higher methane uptake of 3.2 ± 2.5 kg CO 2 eq. ha −1 a −1 for arable soils under organic management can be observed. Only one comparative study on rice paddies has been published up to date. All 19 retrieved studies were conducted in the Northern hemisphere under temperate climate. Further GHG flux measurements in farming system comparisons are required to confirm the results and close the existing knowledge gaps. - Highlights: • Lower area-scaled nitrous oxide emissions from soils managed organically compared

A Hiatus of the Greenhouse Effect

Science.gov (United States)

Song, Jinjie; Wang, Yuan; Tang, Jianping

2016-01-01

The rate at which the global average surface temperature is increasing has slowed down since the end of the last century. This study investigates whether this warming hiatus results from a change in the well-known greenhouse effect. Using long-term, reliable, and consistent observational data from the Earth’s surface and the top of the atmosphere (TOA), two monthly gridded atmospheric and surface greenhouse effect parameters (Ga and Gs) are estimated to represent the radiative warming effects of the atmosphere and the surface in the infrared range from 1979 to 2014. The atmospheric and surface greenhouse effect over the tropical monsoon-prone regions is found to contribute substantially to the global total. Furthermore, the downward tendency of cloud activity leads to a greenhouse effect hiatus after the early 1990 s, prior to the warming pause. Additionally, this pause in the greenhouse effect is mostly caused by the high number of La Niña events between 1991 and 2014. A strong La Niña indicates suppressed convection in the tropical central Pacific that reduces atmospheric water vapor content and cloud volume. This significantly weakened regional greenhouse effect offsets the enhanced warming influence in other places and decelerates the rising global greenhouse effect. This work suggests that the greenhouse effect hiatus can be served as an additional factor to cause the recent global warming slowdown. PMID:27616203

A Hiatus of the Greenhouse Effect.

Science.gov (United States)

Song, Jinjie; Wang, Yuan; Tang, Jianping

2016-09-12

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

A Hiatus of the Greenhouse Effect

Science.gov (United States)

Song, Jinjie; Wang, Yuan; Tang, Jianping

2016-09-01

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

Vermicompost Improves Tomato Yield and Quality and the Biochemical Properties of Soils with Different Tomato Planting History in a Greenhouse Study.

Science.gov (United States)

Wang, Xin-Xin; Zhao, Fengyan; Zhang, Guoxian; Zhang, Yongyong; Yang, Lijuan

2017-01-01

A greenhouse pot test was conducted to study the impacts of replacing mineral fertilizer with organic fertilizers for one full growing period on soil fertility, tomato yield and quality using soils with different tomato planting history. Four types of fertilization regimes were compared: (1) conventional fertilizer with urea, (2) chicken manure compost, (3) vermicompost, and (4) no fertilizer. The effects on plant growth, yield and fruit quality and soil properties (including microbial biomass carbon and nitrogen, [Formula: see text]-N, [Formula: see text]-N, soil water-soluble organic carbon, soil pH and electrical conductivity) were investigated in samples collected from the experimental soils at different tomato growth stages. The main results showed that: (1) vermicompost and chicken manure compost more effectively promoted plant growth, including stem diameter and plant height compared with other fertilizer treatments, in all three types of soil; (2) vermicompost improved fruit quality in each type of soil, and increased the sugar/acid ratio, and decreased nitrate concentration in fresh fruit compared with the CK treatment; (3) vermicompost led to greater improvements in fruit yield (74%), vitamin C (47%), and soluble sugar (71%) in soils with no tomato planting history compared with those in soils with long tomato planting history; and (4) vermicompost led to greater improvements in soil quality than chicken manure compost, including higher pH (averaged 7.37 vs. averaged 7.23) and lower soil electrical conductivity (averaged 204.1 vs. averaged 234.6 μS/cm) at the end of experiment in each type of soil. We conclude that vermicompost can be recommended as a fertilizer to improve tomato fruit quality and yield and soil quality, particularly for soils with no tomato planting history.

Species Composition and Structure of the Communities of Plant-Parasitic and Free-Living Soil Nematodes in the Greenhouses of Botanical Gardens of Ukraine

Directory of Open Access Journals (Sweden)

Gubin A.I.

2014-07-01

Full Text Available Species Composition and Structure of the Communities of Plant-Parasitic and Free-Living Soil Nematodes in the Greenhouses of Botanical Gardens of Ukraine. Gubin, A. I., Sigareva, D. D. — In greenhouses of botanical gardens of Ukraine 81 species of nematodes were found. The richest by the number of species was Tylenchida order that was presented by 25 species (31 % of species composition. The dominant group of nematodes was plant-parasitic (most frequent was Rotylenchus robustus (de Man, 1876 Filipjev, 1936 and Meloidogyne incognita (Kofoid et White, 1919 Chitwood, 1949. The group of saprobiotic nematodes, which was presented by 52 species (64 %, appeared to be the richest by the number of species. It is shown, that formation of nematode communities in greenhouses of botanical gardens was caused by the interaction of many related factors, crucial of which is the composition of plant collections. The structure of communities is quite constant and almost independent of the quantity of nematodes species. Plant-parasitic species dominate by the number and frequency of detection, and represent a kind of a core of nematode communities.

Key Factors Controlling the Growth of Biological Soil Crusts: Towards a Protocol to Produce Biocrusts in Greenhouse Facilities

Science.gov (United States)

Velasco Ayuso, Sergio; María Giraldo Silva, Ana; Nelson, Corey; Barger, Nichole; Antoninka, Anita; Bowker, Matthew; Garcia-Pichel, Ferran

2016-04-01

Biological soil crusts (= biocrusts) are topsoil communities comprise of, but not limited to, cyanobacteria, algae, lichens, and mosses that grow intimately associated with soil particles in drylands. Biocrusts have central ecological roles in these areas as sources of carbon and nutrients, and efficiently retain water and prevent soil erosion, which improves soil structure and promotes soil fertility. However, human activities, such as cattle grazing, hiking or military training, are rapidly striking biocrusts. Although it is well known that the inoculation with cyanobacteria or lichens can enhance the recovery of biocrusts in degraded soils, little is known about the factors that control their growth rates. Using soil and inocula from four different sites located in one cold desert (Utah) and in one hot desert (New Mexico), we performed a fractional factorial experiment involving seven factors (water, light, P, N, calcium carbonate, trace metals and type of inoculum) to screen their effects on the growth of biocrusts. After four months, we measured the concentration of chlorophyll a, and we discovered that water, light and P, N or P+N were the most important factors controlling the growth of biocrusts. In the experimental treatments involving these three factors we measured a similar concentration of chlorophyll a (or even higher) to this found in the field locations. Amplification of the 16S rRNA gene segment using universal bacteria primers revealed a microbial community composition in the biocrusts grown that closely corresponds to initial measurements made on inocula. In summary, based on our success in obtaining biocrust biomass from natural communities in greenhouse facilities, without significantly changing its community composition at the phylum and cyanobacterial level, we are paving the road to propose a protocol to produce a high quality-nursed inoculum aiming to assist restoration of arid and semi-arid ecosystems affected by large-scale disturbances.

Greenhouse gas emissions from a Cu-contaminated soil remediated by in situ stabilization and phytomanaged by a mixed stand of poplar, willows, and false indigo-bush.

Science.gov (United States)

Šimek, M; Elhottová, D; Mench, M; Giagnoni, L; Nannipieri, P; Renella, G

2017-11-02

Phytomanagement of trace element-contaminated soils can reduce soil toxicity and restore soil ecological functions, including the soil gas exchange with the atmosphere. We studied the emission rate of the greenhouse gases (GHGs) CO 2 , CH 4 , and N 2 O; the potential CH 4 oxidation; denitrification enzyme activity (DEA), and glucose mineralization of a Cu-contaminated soil amended with dolomitic limestone and compost, alone or in combination, after a 2-year phytomanagement with a mixed stand of Populus nigra, Salix viminalis, S. caprea, and Amorpha fruticosa. Soil microbial biomass and microbial community composition after analysis of the phospholipid fatty acids (PLFA) profile were determined. Phytomanagement significantly reduced Cu availability and soil toxicity, increased soil microbial biomass and glucose mineralization capacity, changed the composition of soil microbial communities, and increased the CO 2 and N 2 O emission rates and DEA. Despite such increases, microbial communities were evolving toward less GHG emission per unit of microbial biomass than in untreated soils. Overall, the aided phytostabilization option would allow methanotrophic populations to establish in the remediated soils due to decreased soil toxicity and increased nutrient availability.

Effects of three years of simulated nitrogen deposition on soil nitrogen dynamics and greenhouse gas emissions in a Korean pine plantation of northeast China.

Science.gov (United States)

Song, Lei; Tian, Peng; Zhang, Jinbo; Jin, Guangze

2017-12-31

Continuously enhanced nitrogen (N) deposition alters the pattern of N and carbon (C) transformations, and thus influences greenhouse gas emissions. It is necessary to clarify the effect of N deposition on greenhouse gas emissions and soil N dynamics for an accurate assessment of C and N budgets under increasing N deposition. In this study, four simulated N deposition treatments (control [CK: no N addition], low-N [L: 20kgNha -1 yr -1 ], medium-N [M: 40kgNha -1 yr -1 ], and high-N [H: 80kgNha -1 yr -1 ]) were operated from 2014. Carbon dioxide, methane and nitrous oxide fluxes were monitored semimonthly, as were soil variables such as temperature, moisture and the concentrations of total dissolved N (TDN), NO 3 - , NO 2 - , NH 4 + , and dissolved organic N (DON) in soil solutions. The simulated N deposition resulted in a significant increase in TDN, NO 3 - and DON concentrations in soil solutions. The average CO 2 emission rate ranged from 222.6mgCO 2 m -2 h -1 in CK to 233.7mgCO 2 m -2 h -1 in the high-N treatment. Three years of simulated N deposition had no effect on soil CO 2 emission, which was mainly controlled by soil temperature. The mean N 2 O emission rate during the whole 3years was 0.02mgN 2 Om -2 h -1 for CK, which increased significantly to 0.05mgN 2 Om -2 h -1 in the high-N treatment. The N 2 O emission rate positively correlated with NH 4 + concentrations, and negatively correlated with soil moisture. The average CH 4 flux during the whole 3years was -0.74μgCH 4 m -2 h -1 in CK, which increased to 1.41μgCH 4 m -2 h -1 in the low-N treatment. CH 4 flux positively correlated with NO 3 - concentrations. These results indicate that short-term N deposition did not affect soil CO 2 emissions, while CH 4 and N 2 O emissions were sensitive to N deposition. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of land use on greenhouse gas fluxes and soil properties of wetland catchments in the Prairie Pothole Region of North America

Science.gov (United States)

Tangen, Brian A.; Finocchiaro, Raymond G.; Gleason, Robert A.

2015-01-01

Wetland restoration has been suggested as policy goal with multiple environmental benefits including enhancement of atmospheric carbon sequestration. However, there are concerns that increased methane (CH4) emissions associated with restoration may outweigh potential benefits. A comprehensive, 4-year study of 119 wetland catchments was conducted in the Prairie Pothole Region of the north-central U.S. to assess the effects of land use on greenhouse gas (GHG) fluxes and soil properties.

Heterogeneity of O2 dynamics in soil amended with animal manure and implications for greenhouse gas emissions

DEFF Research Database (Denmark)

Zhu, Kun; Bruun, Sander; Larsen, Morten Kobæk

2015-01-01

in soils in which the same amount of solid fraction of pig manure had been distributed in three different ways (mixed, layered, single patch) and which were maintained at awater potential of 5 kPa (corresponding to 91% of water-filled pore space). In parallel, the greenhouse gas emissions (N2O, CO2 and CH4...... the cumulative N2O emissions and reduced the cumulative CO2 fluxes. The faster the anoxia developed, the less the nitrification process appeared to contribute to N2O emissions. No treatment effects on CH4 emissions were observed. Combined high resolution imaging of O2 dynamics and measurements of N2O emission...

Assessing the probability of carbon and greenhouse gas benefit from the management of peat soils

International Nuclear Information System (INIS)

Worrall, F.; Bell, M.J.; Bhogal, A.

2010-01-01

This study proposes a method for assessing the probability that land management interventions will lead to an improvement in the carbon sink represented by peat soils. The method is able to: combine studies of different carbon uptake and release pathways in order to assess changes on the overall carbon or greenhouse gas budget; calculate the probability of the management or restoration leading to an improvement in the budget; calculate the uncertainty in that probability estimate; estimate the equivalent number of complete budgets available from the combination of the literature; test the difference in the outcome of different land management interventions; and provide a method for updating the predicted probabilities as new studies become available. Using this methodology, this study considered the impact of: afforestation, managed burning, drainage, drain-blocking, grazing removal; and revegetation, on the carbon budget of peat soils in the UK. The study showed that afforestation, drain-blocking, revegetation, grazing removal and cessation of managed burning would bring a carbon benefit, whereas deforestation, managed burning and drainage would bring a disbenefit. The predicted probabilities of a benefit are often equivocal as each management type or restoration often leads to increase in uptake in one pathway while increasing losses in another.

Patterns of Carbon Storage and Greenhouse Gas Losses in Urban Residential Lawns

Science.gov (United States)

Contosta, A.; Varner, R.; Xiao, J.

2017-12-01

Population density and housing age are two factors believed to impact carbon (C) storage and greenhouse gas emissions in one of the most extensively managed landscapes in the U.S.: the urban lawn. Previous research focusing on either above- or below-ground C dynamics has also not explicitly considered how they interact to affect the net carbon balance in urban residential areas. We addressed this knowledge gap by quantifying both soil and vegetative C stocks and greenhouse gas fluxes across an urban gradient in Manchester, NH, USA that included 34 lawns comprising three population density categories, five housing age classes, and the interaction between them. Using a combination of both weekly, manual measurements and continuous, automated estimates, we also sampled emissions of CH4, CO2, and N2O within a subset of these lawns that represented a range of citywide population density and housing age characteristics and management practices. We found that neither above- nor below-ground C storage varied with population density, but both differed among housing age classes. Soil C storage increased with housing age and was highest in the oldest lawns sampled. By contrast, C stocks in aboveground, woody biomass was highest at intermediate ages and lowest in older and new parcels. Unlike C stocks, soil greenhouse gas emissions did not change among population density categories, housing age classes, or with irrigation and fertilization management, but instead followed temporal trends in soil moisture and temperature. Overall, our results suggest that drivers of C storage and greenhouse gas losses in urban residential areas may not be uniform and their accurate representation in Earth system models may require a variety of approaches.

Evaluation of the greenhouse effect gases (CO2, CH4, N2O) in grass land and in the grass breeding. Greenhouse effect gases prairies. report of the first part of the project December 2002

International Nuclear Information System (INIS)

Soussana, J.F.

2002-12-01

In the framework of the Kyoto protocol on the greenhouse effect gases reduction, many ecosystems as the prairies can play a main role for the carbon sequestration in soils. The conservation of french prairies and their management adaptation could allow the possibility of carbon sequestration in the soils but also could generate emissions of CO 2 and CH 4 (by the breeding animals on grass) and N 2 O (by the soils). This project aims to establish a detailed evaluation of the contribution of the french prairies to the the greenhouse effect gases flux and evaluate the possibilities of reduction of the emissions by adaptation of breeding systems. (A.L.B.)

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

Science.gov (United States)

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

2015-08-01

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

Greenhouse gas fluxes from agricultural soils under organic and non-organic management — A global meta-analysis

Energy Technology Data Exchange (ETDEWEB)

Skinner, Colin, E-mail: colin.skinner@fibl.org [Research Institute of Organic Agriculture (FiBL), Ackerstrasse 21, 5070 Frick (Switzerland); Gattinger, Andreas, E-mail: andreas.gattinger@fibl.org [Research Institute of Organic Agriculture (FiBL), Ackerstrasse 21, 5070 Frick (Switzerland); Muller, Adrian, E-mail: adrian.mueller@fibl.org [Research Institute of Organic Agriculture (FiBL), Ackerstrasse 21, 5070 Frick (Switzerland); Mäder, Paul, E-mail: paul.maeder@fibl.org [Research Institute of Organic Agriculture (FiBL), Ackerstrasse 21, 5070 Frick (Switzerland); Fließbach, Andreas, E-mail: andreas.fliessbach@fibl.org [Research Institute of Organic Agriculture (FiBL), Ackerstrasse 21, 5070 Frick (Switzerland); Stolze, Matthias, E-mail: matthias.stolze@fibl.org [Research Institute of Organic Agriculture (FiBL), Ackerstrasse 21, 5070 Frick (Switzerland); Ruser, Reiner, E-mail: reiner.ruser@uni-hohenheim.de [Fertilisation and Soil Matter Dynamics (340i), Institute of Crop Science, University of Hohenheim, Fruwirthstraße 20, 70599 Stuttgart (Germany); Niggli, Urs, E-mail: urs.niggli@fibl.org [Research Institute of Organic Agriculture (FiBL), Ackerstrasse 21, 5070 Frick (Switzerland)

2014-01-01

It is anticipated that organic farming systems provide benefits concerning soil conservation and climate protection. A literature search on measured soil-derived greenhouse gas (GHG) (nitrous oxide and methane) fluxes under organic and non-organic management from farming system comparisons was conducted and followed by a meta-analysis. Up to date only 19 studies based on field measurements could be retrieved. Based on 12 studies that cover annual measurements, it appeared with a high significance that area-scaled nitrous oxide emissions from organically managed soils are 492 ± 160 kg CO{sub 2} eq. ha{sup −1} a{sup −1} lower than from non-organically managed soils. For arable soils the difference amounts to 497 ± 162 kg CO{sub 2} eq. ha{sup −1} a{sup −1}. However, yield-scaled nitrous oxide emissions are higher by 41 ± 34 kg CO{sub 2} eq. t{sup −1} DM under organic management (arable and use). To equalize this mean difference in yield-scaled nitrous oxide emissions between both farming systems, the yield gap has to be less than 17%. Emissions from conventionally managed soils seemed to be influenced mainly by total N inputs, whereas for organically managed soils other variables such as soil characteristics seemed to be more important. This can be explained by the higher bioavailability of the synthetic N fertilisers in non-organic farming systems while the necessary mineralisation of the N sources under organic management leads to lower and retarded availability. Furthermore, a higher methane uptake of 3.2 ± 2.5 kg CO{sub 2} eq. ha{sup −1} a{sup −1} for arable soils under organic management can be observed. Only one comparative study on rice paddies has been published up to date. All 19 retrieved studies were conducted in the Northern hemisphere under temperate climate. Further GHG flux measurements in farming system comparisons are required to confirm the results and close the existing knowledge gaps. - Highlights: • Lower area-scaled nitrous

Greenhouse gas emissions from Savanna ( Miombo ) woodlands ...

African Journals Online (AJOL)

Natural vegetation represents an important sink for greenhouse gases (GHGs); however, there is relatively little information available on emissions from southern African savannas. The effects of clearing savanna woodlands for crop production on soil fluxes of N2O, CO2 and CH4 were studied on clay (Chromic luvisol) and ...

Effects of land cover change on litter decomposition and soil greenhouse gas fluxes in subtropical Hong Kong

Science.gov (United States)

Ngar Wong, Chun; Lai, Derrick Yuk Fo

2017-04-01

Nowadays, over 50% of the world's population live in urbanized areas and the level of urbanization varies substantially across countries. Intense human activities and management associated with urbanization can alter the microclimate and biogeochemical processes in urban areas, which subsequently affect the provision of ecosystem services and functions. Litter decomposition and soil greenhouse gas (GHG) exchange play an important role in governing nutrient cycling and future climate change, respectively. Yet, the effects of urbanization on these two biogeochemical processes remain uncertain and not well understood, especially in subtropical and high-density cities. This study aims to examine the effects of urbanization on decomposition and GHG fluxes among four land covers- natural forest, urban forest, farmland and roadside planter, in Hong Kong based on litterbag experiment and closed chamber measurements for one full year. Litter decomposition rate was significantly lower in farmland than in other land cover types. Significant differences in CO2 emission were detected among the four land cover types (pmean N2O fluxes, respectively. The emission of CO2 was positively correlated with soil potassium content, while CH4 and N2O flux increased markedly with soil temperature and nitrate nitrogen content, respectively. The results obtained in this study will enhance our understanding on urban ecosystem and be useful for recommending sustainable management strategies for conservation of ecosystem services in urban areas.

Soil properties, greenhouse gas emissions and crop yield under compost, biochar and co-composted biochar in two tropical agronomic systems

Energy Technology Data Exchange (ETDEWEB)

Bass, Adrian M., E-mail: adrian.bass@glasgow.ac.uk [Centre for Tropical Environmental and Sustainability Science, College of Science, Technology and Engineering, James Cook University, Cairns, Queensland 4870 (Australia); Bird, Michael I. [Centre for Tropical Environmental and Sustainability Science, College of Science, Technology and Engineering, James Cook University, Cairns, Queensland 4870 (Australia); Kay, Gavin [Terrain Natural Resource Management, 2 Stitt Street, Innisfail, Queensland 4860 (Australia); Muirhead, Brian [Northern Gulf Resource Management Group, 317 Byrnes Street, Mareeba, Queensland 4880 (Australia)

2016-04-15

ABSTRACT: The addition of organic amendments to agricultural soils has the potential to increase crop yields, reduce dependence on inorganic fertilizers and improve soil condition and resilience. We evaluated the effect of biochar (B), compost (C) and co-composted biochar (COMBI) on the soil properties, crop yield and greenhouse gas emissions from a banana and a papaya plantation in tropical Australia in the first harvest cycle. Biochar, compost and COMBI organic amendments improved soil properties, including significant increases in soil water content, CEC, K, Ca, NO{sub 3}, NH{sub 4} and soil carbon content. However, increases in soil nutrient content and improvements in physical properties did not translate to improved fruit yield. Counter to our expectations, banana crop yield (weight per bunch) was reduced by 18%, 12% and 24% by B, C and COMBI additions respectively, and no significant effect was observed on the papaya crop yield. Soil efflux of CO{sub 2} was elevated by addition of C and COMBI amendments, likely due to an increase in labile carbon for microbial processing. Our data indicate a reduction in N{sub 2}O flux in treatments containing biochar. The application of B, C and COMBI amendments had a generally positive effect on soil properties, but this did not translate into a crop productivity increase in this study. The benefits to soil nutrient content, soil carbon storage and N{sub 2}O emission reduction need to be carefully weighed against potentially deleterious effects on crop yield, at least in the short-term. - Highlights: • Biochar and compost amendment has potential to improve tropical agriculture. • We monitored soil health, gas fluxes and crop yield under biochar and compost. • Biochar improved soil nutrient content, water retention and reduced N{sub 2}O emissions. • Biochar significantly reduced banana yield performance and did not affect papaya yield. • Organic amendment is not an ‘always win’ scenario for tropical

Soil properties, greenhouse gas emissions and crop yield under compost, biochar and co-composted biochar in two tropical agronomic systems

International Nuclear Information System (INIS)

Bass, Adrian M.; Bird, Michael I.; Kay, Gavin; Muirhead, Brian

2016-01-01

ABSTRACT: The addition of organic amendments to agricultural soils has the potential to increase crop yields, reduce dependence on inorganic fertilizers and improve soil condition and resilience. We evaluated the effect of biochar (B), compost (C) and co-composted biochar (COMBI) on the soil properties, crop yield and greenhouse gas emissions from a banana and a papaya plantation in tropical Australia in the first harvest cycle. Biochar, compost and COMBI organic amendments improved soil properties, including significant increases in soil water content, CEC, K, Ca, NO_3, NH_4 and soil carbon content. However, increases in soil nutrient content and improvements in physical properties did not translate to improved fruit yield. Counter to our expectations, banana crop yield (weight per bunch) was reduced by 18%, 12% and 24% by B, C and COMBI additions respectively, and no significant effect was observed on the papaya crop yield. Soil efflux of CO_2 was elevated by addition of C and COMBI amendments, likely due to an increase in labile carbon for microbial processing. Our data indicate a reduction in N_2O flux in treatments containing biochar. The application of B, C and COMBI amendments had a generally positive effect on soil properties, but this did not translate into a crop productivity increase in this study. The benefits to soil nutrient content, soil carbon storage and N_2O emission reduction need to be carefully weighed against potentially deleterious effects on crop yield, at least in the short-term. - Highlights: • Biochar and compost amendment has potential to improve tropical agriculture. • We monitored soil health, gas fluxes and crop yield under biochar and compost. • Biochar improved soil nutrient content, water retention and reduced N_2O emissions. • Biochar significantly reduced banana yield performance and did not affect papaya yield. • Organic amendment is not an ‘always win’ scenario for tropical agriculture.

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

Science.gov (United States)

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

2017-01-01

Recently, greenhouse vegetable production (GVP) has grown rapidly and counts a large proportion of vegetable production in China. In this study, the accumulation, health risk and threshold values of selected heavy metals were evaluated systematically. A total of 120 paired soil and vegetable samples were collected from three typical intensive GVP systems along the Yellow Sea of China. Mean concentrations of Cd, As, Hg, Pb, Cu and Zn in greenhouse soils were 0.21, 7.12, 0.05, 19.81, 24.95 and 94.11 mg kg -1 , respectively. Compared to rootstalk and fruit vegetables, leafy vegetables had relatively high concentrations and transfer factors of heavy metals. The accumulation of heavy metals in soils was affected by soil pH and soil organic matter. The calculated hazard quotients (HQ) of the heavy metals by vegetable consumption decreased in the order of leafy > rootstalk > fruit vegetables with hazard index (HI) values of 0.61, 0.33 and 0.26, respectively. The HI values were all below 1, which indicates that there is a low risk of greenhouse vegetable consumption. Soil threshold values (STVs) of heavy metals in GVP system were established according to the health risk assessment. The relatively lower transfer factors of rootstalk and fruit vegetables and higher STVs suggest that these types of vegetables are more suitable for cultivation in greenhouse soils. This study will provide an useful reference for controlling heavy metals and developing sustainable GVP. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

Science.gov (United States)

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

2016-09-01

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

Phosphorus and greenhouse gas dynamics in a drained calcareous wetland soil in Minnesota.

Science.gov (United States)

Berryman, Erin M; Venterea, Rodney T; Baker, John M; Bloom, Paul R; Elf, Brandy

2009-01-01

Restoration of wetland hydrology can produce ecological benefits but may have unintended consequences. We examined effects of altered water level on release of dissolved reactive phosphorus (DRP) and greenhouse gases (GHG) in soil cores from a marsh being evaluated for restoration. We also measured field concentrations of DRP and other constituents in wetland porewater. Intact cores from a sampling location with higher Fe and lower calcium carbonate (CaCO(3)) contents released more DRP than another location, and displayed higher DRP under completely saturated compared to partly drained conditions. Porewater samples collected from the high-Fe location also contained higher DRP levels. Chemical data suggest that redox-driven reactions largely controlled DRP levels at the high-Fe site, while CaCO(3) adsorption was more important at the low-Fe site. Over the long term, water table elevation may attenuate P draining from the wetland due to decreased mineralization. However, such measures may increase P release in the short term. Raising the water level in soil cores resulted in decreased nitrous oxide (N(2)O) emissions, increased methane (CH(4)) emissions, and an overall increase in total global warming potential (GWP). The proportion of total GWP contributed by N(2)O decreased from 14% to < or = 1% as water level was raised, while the proportion contributed by CH(4) increased from 10 to 20% to 60 to 80%. Restoration of hydrology in the Rice Lake wetland has the potential to affect both local water quality and global air quality. These combined effects complicate the cost-to-benefit analysis of such wetland restoration efforts.

Evaluation of Crops Sensitivity to Atrazine Soil Residual

Directory of Open Access Journals (Sweden)

E Izadi

2012-02-01

Full Text Available Abstract In order to study the sensitivity of 9 crops to atrazine soil residual, two separate experiments were conducted in field and greenhouse conditions. First experiment was conducted in a field with treated soil by atrazine based on split plot and the results evaluated in greenhouse conditions. Treatments in the field experiment included two organic manure application rates (0 and 50 t/ha as main plots and 2 atrazine application rates (2 and 4 kg/ha atrazine a.i. as sob plots. After corn harvesting soil was sampled at 0-15 cm surface layer in each plots in 15 points, after mixing the samples. Wheat, barley, sugar beet, pea, lens and colza planted in pots at greenhouse. Second experiment conducted in greenhouse conditions for evaluation of atrazine soil residual in completely randomized design. Treatments included atrazine soil residual concentrations (0, 0.2, 0.5, 1, 5, 10 and 15 mg/kg soil and crops included wheat, barley, sugar beet, pea, lens, rape, bean and tomato. Results showed that atrazine residue had no effect on crops growth in field experiment treated with atrazine. It seems that atrazine residue in filed soil is lower that its damage threshold for crops or maybe for its fast removal in field than in control conditions. But in bioassay experiment (greenhouse experiment crops response to atrazine residues were different. Results showed that onion and pea were most susceptible ant tolerant crops between studied species and based of ED50 parameter the other crops tolerance to total residue ranked as: pea< bean< lentil< sugar beet< tomato< barley< wheat< rape< onion. Keywords: Atrazine residue, Pea, Bean, Lentil, Sugar beet, Barley, Wheat, Rape, Tomato

Ecology of Fungus Gnats (Bradysia spp.) in Greenhouse Production Systems Associated with Disease-Interactions and Alternative Management Strategies.

Science.gov (United States)

Cloyd, Raymond A

2015-04-09

Fungus gnats (Bradysia spp.) are major insect pests of greenhouse-grown horticultural crops mainly due to the direct feeding damage caused by the larvae, and the ability of larvae to transmit certain soil-borne plant pathogens. Currently, insecticides and biological control agents are being used successively to deal with fungus gnat populations in greenhouse production systems. However, these strategies may only be effective as long as greenhouse producers also implement alternative management strategies such as cultural, physical, and sanitation. This includes elimination of algae, and plant and growing medium debris; placing physical barriers onto the growing medium surface; and using materials that repel fungus gnat adults. This article describes the disease-interactions associated with fungus gnats and foliar and soil-borne diseases, and the alternative management strategies that should be considered by greenhouse producers in order to alleviate problems with fungus gnats in greenhouse production systems.

Ecology of Fungus Gnats (Bradysia spp. in Greenhouse Production Systems Associated with Disease-Interactions and Alternative Management Strategies

Directory of Open Access Journals (Sweden)

Raymond A. Cloyd

2015-04-01

Full Text Available Fungus gnats (Bradysia spp. are major insect pests of greenhouse-grown horticultural crops mainly due to the direct feeding damage caused by the larvae, and the ability of larvae to transmit certain soil-borne plant pathogens. Currently, insecticides and biological control agents are being used successively to deal with fungus gnat populations in greenhouse production systems. However, these strategies may only be effective as long as greenhouse producers also implement alternative management strategies such as cultural, physical, and sanitation. This includes elimination of algae, and plant and growing medium debris; placing physical barriers onto the growing medium surface; and using materials that repel fungus gnat adults. This article describes the disease-interactions associated with fungus gnats and foliar and soil-borne diseases, and the alternative management strategies that should be considered by greenhouse producers in order to alleviate problems with fungus gnats in greenhouse production systems.

Economic aspects of energy saving in greenhouses: physical considerations

CERN Document Server

Danloy, L; Gay, J B; Mercier, J A; Reist, A

1989-01-01

An important result of experiments carried out over the past six years in a trial greenhouse at CERN (The European Organization for Nuclear Research, Geneva, Switzerland) was the development of a simple and precise method for calculating the energy requirements of a glasshouse; this is valid for any type of greenhouse and climate. An economic study is made using the above method for evaluating the financial effectiveness of various energy-saving methods: double glazing of the side walls, low emissivity glass 'Hortiplus' roofing, soil level heating and a thermal screen.

Organic Matter Effect on Glomus Intrarradices in Beans (Phaseolus Vulgaris L. Growth Cultivated in Soils with Two Sources of Water under Greenhouse Conditions

Directory of Open Access Journals (Sweden)

A. K. Gardezi

2014-02-01

Full Text Available The objective of this research was to evaluate the effect of organic matter on the association with Glomus intrarradices and soil contamination on beans (Phaseolus vulgaris L.. The study was done under greenhouse conditions at the Montecillo Campus of the Postgraduate College, Mexico. Two soils were used, one irrigated with sewage water and the other one with clean water from a well. Half of the plants were inoculated with Glomus intrarradices. Vermicompost was used as a source of organic matter. There were highly significant increases (p≤0.05 in all the variables recorded due to the application of organic matter, and to the inoculation with Glomus intarradices. The irrigation source of the soils used for this experiment only had a significant effect (p≤0.05 on pod number and nitrogen fixation. The best growth and grain yield occurred with inoculated plants and supplementary organic matter.

Cooling of a polyethylene tunnel type greenhouse by means of a rock bed

Energy Technology Data Exchange (ETDEWEB)

Kurklu, Ahmet; Bilgin, Sefai [Akdeniz Univ., Dept. of Agricultural Mechanisation, Antalya (Turkey)

2004-10-01

An experiment was conducted to cool a 15 m{sup 2} ground area plastic-tunnel-type greenhouse by the use of a rock bed. An identical greenhouse with no rock bed was also erected for control purposes. Two rock-bed canals, each with the dimensions of 3 x l.25 x 0.75 m, were dug in the soil of the experimental greenhouse. After the canals were filled with the rocks and insulated, the top surface was covered by a soil layer of thickness enough for the root development depth of the plants. Air was pushed through the rock bed by a centrifugal fan with a 1100 m{sup 3}/h flow rate. Energy stored in the rock bed during the day was dumped outside the greenhouse at night using the cooler outside air. The results of the measurements showed that the rock-bed system maintained air temperature 14 deg C lower at maximum in the experimental greenhouse than the control one. The temperature difference seemed to increase with increasing solar radiation and outside air temperature. Relative humidity during the day remained at about 40% in the experimental greenhouse and was always higher than that in the control one. The coefficient of performance (COP) of the rock-bed system was higher than 3 in general, and it was observed that this value increased with decreasing rock-bed temperature. The average solar collection efficiency was 38%. The rock-bed system seems to have a significant potential for cooling applications in greenhouses. (Author)

Design and Development a Control and Monitoring System for Greenhouse Conditions Based-On Multi Agent System

Directory of Open Access Journals (Sweden)

Seyed Hamidreza Kasaei

2011-12-01

Full Text Available The design of a multi-agent system for integrated management of greenhouse production is described. The model supports the integrated greenhouse production, with targets set to quality and quantity of produce with the minimum possible cost in resources and environmental consequences.
In this paper, we propose a real time and robust system for monitoring and control of the greenhouse condition which can automatically control of greenhouse temperature, lights, humidity, CO2 concentration, sunshine, pH, salinity, water available, soil temperature and soil nutrient for efficient production. We will propose a multi-agent methodology for integrated management systems in greenhouses. In this regards wireless sensor networks play a vital role to monitor
greenhouse and environment parameters. Each control process of the greenhouse environment is modeled as an autonomous agent with its own inputs, outputs and its own interactions with the other agents. Each agent acts autonomously, as it knows a priori the desired environmental setpoints. Many researchers have been making attempts to develop the greenhouse environment management system. The existing environment management systems are bulky, very costly and difficult to maintain. In the last years, Multi Agent Systems and Wireless Sensor Networks are becoming important solutions to this problem. This paper describes the implementation and
configuration of the wireless sensor network to monitor and control various parameter of greenhouse. The developed system is simple, cost effective, and easily installable.

The effective mitigation of greenhouse gas emissions from rice paddies without compromising yield by early-season drainage

DEFF Research Database (Denmark)

Islam, Syed Faiz-Ul; van Groenigen, Jan Willem; Jensen, Lars Stoumann

2018-01-01

Global rice production systems face two opposing challenges: the need to increase production to accommodate the world's growing population while simultaneously reducing greenhouse gas (GHG) emissions. Adaptations to drainage regimes are one of the most promising options for methane mitigation...... only. A combination of (short or long) ED drainage and one MD drainage episode was found to be the most effective in mitigating CH4 emissions without negatively affecting yield. In particular, compared with CF, the long early-season drainage treatments LE+SM and LE+LM significantly (p

Spatiotemporal dynamics of phosphorus release, oxygen consumption and greenhouse gas emissions after localised soil amendment with organic fertilisers

Energy Technology Data Exchange (ETDEWEB)

Christel, Wibke [Department for Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C (Denmark); Department of Commerce, Industry and Agriculture, Danish Environmental Protection Agency, 1401 Copenhagen C (Denmark); Zhu, Kun [Department for Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C (Denmark); College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193 (China); Hoefer, Christoph [Rhizosphere Ecology and Biogeochemistry Group, Department of Forest and Soil Sciences, University of Natural Resources and Life Sciences, Vienna, Konrad-Lorenz-Strasse 24, 3430 Tulln (Austria); Kreuzeder, Andreas [Rhizosphere Ecology and Biogeochemistry Group, Department of Forest and Soil Sciences, University of Natural Resources and Life Sciences, Vienna, Konrad-Lorenz-Strasse 24, 3430 Tulln (Austria); Land Salzburg, Natur- und Umweltschutz, Gewerbe (Abteilung 5), Michael-Pacher-Straße 36, 5020 Salzburg (Austria); Santner, Jakob [Rhizosphere Ecology and Biogeochemistry Group, Department of Forest and Soil Sciences, University of Natural Resources and Life Sciences, Vienna, Konrad-Lorenz-Strasse 24, 3430 Tulln (Austria); Division of Agronomy, Department of Crop Sciences, University of Natural Resources and Life Sciences, Vienna, Konrad-Lorenz-Strasse 24, 3430 Tulln (Austria); Bruun, Sander; Magid, Jakob [Department for Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C (Denmark); Jensen, Lars Stoumann, E-mail: lsj@plen.ku.dk [Department for Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C (Denmark)

2016-06-01

Organic fertilisation inevitably leads to heterogeneous distribution of organic matter and nutrients in soil, i.e. due to uneven surface spreading or inhomogeneous incorporation. The resulting localised hotspots of nutrient application will induce various biotic and abiotic nutrient turnover processes and fixation in the residuesphere, giving rise to distinct differences in nutrient availability, soil oxygen content and greenhouse gas (GHG) production. In this study we investigated the spatiotemporal dynamics of the reaction of manure solids and manure solids char with soil, focusing on their phosphorus (P) availability, as current emphasis on improving societal P efficiency through recycling waste or bio-based fertilisers necessitates a sound understanding of their behaviour. Soil layers amended at a constant P application rate with either pig manure solids or char made from pig manure solids were incubated for three weeks between layers of non-amended, P-depleted soil. Spatial and temporal changes in and around the amendment layers were simultaneously investigated in this study using a sandwich sensor consisting of a planar oxygen optode and multi-element diffusive gradients in thin films (DGT) gels, combined with GHG emission measurements. After three weeks of incubation, the soil containing a layer amended with manure solids had a lower overall O{sub 2} content and had emitted significantly more CO{sub 2} than the non-amended control or the char-amended soil. The P availability from manure solids was initially higher than that from the char, but decreased over time, whereas from the char-amended layer P availability increased in the same period. In both treatments, increases in P availability were confined to the amended soil layer and did not greatly affect P availability in the directly adjacent soil layers during the three-week incubation. These results highlight the importance of placing organic P fertilisers close to where the plant roots will grow in

Spatiotemporal dynamics of phosphorus release, oxygen consumption and greenhouse gas emissions after localised soil amendment with organic fertilisers

International Nuclear Information System (INIS)

Christel, Wibke; Zhu, Kun; Hoefer, Christoph; Kreuzeder, Andreas; Santner, Jakob; Bruun, Sander; Magid, Jakob; Jensen, Lars Stoumann

2016-01-01

Organic fertilisation inevitably leads to heterogeneous distribution of organic matter and nutrients in soil, i.e. due to uneven surface spreading or inhomogeneous incorporation. The resulting localised hotspots of nutrient application will induce various biotic and abiotic nutrient turnover processes and fixation in the residuesphere, giving rise to distinct differences in nutrient availability, soil oxygen content and greenhouse gas (GHG) production. In this study we investigated the spatiotemporal dynamics of the reaction of manure solids and manure solids char with soil, focusing on their phosphorus (P) availability, as current emphasis on improving societal P efficiency through recycling waste or bio-based fertilisers necessitates a sound understanding of their behaviour. Soil layers amended at a constant P application rate with either pig manure solids or char made from pig manure solids were incubated for three weeks between layers of non-amended, P-depleted soil. Spatial and temporal changes in and around the amendment layers were simultaneously investigated in this study using a sandwich sensor consisting of a planar oxygen optode and multi-element diffusive gradients in thin films (DGT) gels, combined with GHG emission measurements. After three weeks of incubation, the soil containing a layer amended with manure solids had a lower overall O_2 content and had emitted significantly more CO_2 than the non-amended control or the char-amended soil. The P availability from manure solids was initially higher than that from the char, but decreased over time, whereas from the char-amended layer P availability increased in the same period. In both treatments, increases in P availability were confined to the amended soil layer and did not greatly affect P availability in the directly adjacent soil layers during the three-week incubation. These results highlight the importance of placing organic P fertilisers close to where the plant roots will grow in order to

Teaching About the Links Between Soils and Climate: An International Year of Soil Outreach by the Soil Science Society of America

Science.gov (United States)

Brevik, Eric C.

2015-04-01

Soil scientists are well aware of the intimate links that exist between soils and climate, but the same is not always true of the broader population. In an attempt to help address this, the Soil Science Society of America (SSSA) has designated the theme "Soils and Climate" for the month of November, 2015 as part of the SSSA International Year of Soil (IYS) celebration. The topic has been further subdivided into three subthemes: 1) carbon sequestration and greenhouse gases, 2) Soils and past environments, and 3) Desertification and drought. Each subtheme outreach has two parts 1) lesson plans that K-12 educators can use in their classrooms, and 2) materials that a trained soil scientist can present to the general public. Activities developed for the theme include classroom activities to accompany an online game that students can play to see how farm management choices influence greenhouse gas emissions, questions to go with a vermicomposting activity, and discussion session questions to go with a movie on the USA Dust Bowl. All materials are available online free of charge. The Soils and Climate materials can be found at https://www.soils.org/iys/12-month-resources/november; all of the SSSA IYS materials can be found at https://www.soils.org/iys.

Concentration of lead and zinc in greenhouse cucumbers of Hamadan province in 2012

Directory of Open Access Journals (Sweden)

Z BigMohammadi

2013-08-01

Full Text Available Heavy metal pollution of agricultural soils is a major environmental problem that can affect plant production, food safety and human health. Soil contamination with heavy metals occurs as a result of human activities. Heavy metals can easily accumulate in edible tissues of leafy vegetables, fruits and seeds. Few studies have been conducted on heavy metals concentration in soil and greenhouse crops. Therefore, this study aimed to determine the concentrations of lead (Pb and zinc (Zn in greenhouse cucumbers produced in Hamadan province. The concentrations of heavy metals were measured using atomic emission method. Results showed that the mean concentrations of Pb and Zn in cucumber samples were 0.33 and 3.14 mg/kg, respectively. Also the results of the statistical analysis revealed a negative correlation between the measured concentrations. Moreover, the concentration of Zn in the samples obtained from Hamadan greenhouses and lead concentration in Tuyserkan, Famenin, as well as Malayer samples were above the recommended limits. Daily intake amounts of Pb and Zn from vegetables consumption for three age categories (children, adolescents, and adults were calculated. In conclusion, daily intake of Pb and Zn were determined below the recommended limits.

Residual Effect of Lead on Early Growth of Fluted Pumpkin ( Telfairia ...

African Journals Online (AJOL)

The greenhouse and field trials were carried out at Faculty of Agriculture, University of Benin, Benin City to find out the residual influence of Pb on some Telfairia occidentalis agronomic characters and soil chemical properties. The soils used were previously treated with 0, 50, 100, 200 mg per 5 kg soil in the greenhouse ...

Water deficit effects on maize yields modeled under current and greenhouse climates

International Nuclear Information System (INIS)

Muchow, R.C.; Sinclair, T.R.

1991-01-01

The availability of water imposes one of the major limits on rainfed maize (Zea mays L.) productivity. This analysis was undertaken in an attempt to quantify the effects of limited water on maize growth and yield by extending a simple, mechanistic model in which temperature regulates crop development and intercepted solar radiation is used to calculate crop biomass accumulation. A soil water budget was incorporated into the model by accounting for inputs from rainfall and irrigation, and water use by soil evaporation and crop transpiration. The response functions of leaf area development and crop gas exchange to the soil water budget were developed from experimental studies. The model was used to interpret a range of field experiments using observed daily values of temperature, solar radiation, and rainfall or irrigation, where water deficits of varying durations developed at different stages of growth. The relative simplicity of the model and its robustness in simulating maize yields under a range of water-availability conditions allows the model to be readily used for studies of crop performance under alternate conditions. One such study, presented here, was a yield assessment for rainfed maize under possible greenhouse climates where temperature and atmospheric CO 2 concentration were increased. An increase in temperature combined with decreased rainfall lowered grain yield, although the increase in crop water use efficiency associated with elevated CO 2 concentration ameliorated the response to the greenhouse climate. Grain yields for the greenhouse climates as compared to current conditions increased, or decreased only slightly, except when the greenhouse climate was assumed to result in severly decreased rainfall

Microorganisms applying for artificial soil regeneration technology in space greenhouses

Science.gov (United States)

Krivobok, A. S.

2012-04-01

increased up to 30 % from initial roots dry weight. When the bacterial association derived from organic compost was used, the roots dry weight reduction was not exceeded 20 % in liquid state fermentation after 21 days. But the total cellulose was quietly steady, only the readily accessible soluble fractions were consumed. It was found that the most promising microorganisms for pointed task are anaerobic, thermophilic bacterium Clostridium thermocellum F9 and Caldicellulosiruptor bescii DSM 6725. It has been shown that its' in the liquid medium with the roots residuals during 10 days provides root biomass degradation up to 45 % and double decrease of crystalline cellulose. It's known that one of the possible ways to improve biodegradation process efficiency is applying of physical-chemical pretreatment for plant biomass. We used the pretreatment of BIONA substrate in microwave irradiation in 0,7 % sodium hydroxide water solution with addition of 0,5 % of hydrogen peroxide. It has allowed hydrolyzing the roots biomass partially and making the cellulose portion accessible to subsequent biodegradation. The alkaline pretreatment and the subsequent degradation by anaerobic, thermophilic bacterium Clostridium thermocellum, had lead to root biomass decrease up to 85% during 10 days. The examined procedure has allowed to restore the initial pore space volume of BIONA substrate and its' hydro-physical properties. It has made used-up BIONA suitable for the subsequent plant cultivation. The obtained results are the basis for future development of fibrous artificial soils regeneration technologies particularly for space greenhouses

Sensitivity of greenhouse summer dryness to changes in plant rooting characteristics

Science.gov (United States)

Milly, P.C.D.

1997-01-01

A possible consequence of increased concentrations of greenhouse gases in Earth's atmosphere is "summer dryness," a decrease of summer plant-available soil water in middle latitudes, caused by increased availability of energy to drive evapotranspiration. Results from a numerical climate model indicate that summer dryness and related changes of land-surface water balances are highly sensitive to possible concomitant changes of plant-available water-holding capacity of soil, which depends on plant rooting depth and density. The model suggests that a 14% decrease of the soil volume whose water is accessible to plant roots would generate the same summer dryness, by one measure, as an equilibrium doubling of atmospheric carbon dioxide. Conversely, a 14% increase of that soil volume would be sufficient to offset the summer dryness associated with carbon-dioxide doubling. Global and regional changes in rooting depth and density may result from (1) plant and plant-community responses to greenhouse warming, to carbon-dioxide fertilization, and to associated changes in the water balance and (2) anthropogenic deforestation and desertification. Given their apparently critical role, heretofore ignored, in global hydroclimatic change, such changes of rooting characteristics should be carefully evaluated using ecosystem observations, theory, and models.

Greenhouse gas emissions trading: Cogen case studies in the early trading market

International Nuclear Information System (INIS)

Buerer, Mary Jean

2001-01-01

An increasing number of companies are interested in opportunities to trade their reduction in greenhouse gas emissions from cogeneration on the emerging greenhouse gas emissions market. Only the UK and Denmark currently have emissions trading schemes, but they are under development in other European countries. Two frameworks currently exist for trading. Baseline-and-credit trading is used in Canada where companies can take part in two voluntary schemes (Greenhouse Gas Emission Reduction Trading Pilot or Clean Air Canada Inc). An example project from the CHP unit at DuPont's Maitland chemical production facility is given, with details of the baselines and calculations used. The other option is company-wide emissions trading. The example given here features the CHP units at BP's refinery and chemicals operations in Texas. The potential revenue from emission reduction projects could help to boost the economics of cogeneration projects

Non-target effects of the microbial control agents Pseudomonas fluorescens DR54 and Clonostachys rosea IK726 in soils cropped with barley followed by sugar beet: a greenhouse assessment

DEFF Research Database (Denmark)

Johansen, A.; Knudsen, I. M. B.; Binnerup, S. J.

2005-01-01

Non-target effects of a bacterial (Pseudomonas fluorescens DR54) and a fungal (Clonostachys rosea IK726) microbial control agent (MCA), on the indigenous microbiota in bulk soil and rhizosphere of barley, and subsequent a sugar beet crop, were studied in a greenhouse experiment. MCAs were...... introduced by seed and soil inoculation. Bulk and rhizosphere soils were sampled regularly during the growth of barley and sugar beet. The soils were assayed for the fate of MCAs and various features of the indigenous soil microbiota. At the end of the experiment (193 d), DR54 and IK726 had declined...... by a factor of 106 and 20, respectively, and DR54 showed a short-lasting growth increase in the sugar beet rhizosphere. In general, the non-target effects were small and transient. IK726 seemed to have general stimulating effects on soil enzyme activity and the soil microbiota, and resulted in a significant...

Nitrogen utilization of vegetables grown under plastic greenhouse conditions in Ankara using 15N technique

International Nuclear Information System (INIS)

Halitligil, M.B.; Kislal, H.; Sirin, H.; Sirin, C.; Kilicaslan, A.

2004-01-01

In order to find suitable varieties of tomato, pepper and cucumber for plastic greenhouse conditions in Ankara and eventually to identify the best N fertilizer rate greenhouse experiments were conducted for two years. Yazgi F 1 variety for tomato, Hizir F 1 variety for cucumber and Serademre 8 variety for pepper were chosen to be the suitable varieties to grow in the plastic greenhouse conditions in Ankara. Five N treatments [N 0 =0, N 1 =150, N 2 =300, and N 3 =450 kg/ha; also, soil N application treatment (N soil ) equivalent to the fertigation treatment of 300 kg/ha was included for tomato and pepper, however N rates for cucumber was 131, 266 and 339 kg N/ha; N soil being 266 kg N/ha] were investigated using 15 N labeled urea fertilizer. Significantly higher marketable fresh fruit and total dry matter yields and N uptakes values were obtained from N 3 treatments for tomato and cucumber, but from N 2 treatment for pepper. Also, significantly higher yields, N uptakes and % NUE values were obtained when the same amount of N fertilizer is applied through fertigation compared to the treatment where N fertilizer applied to the soil then drip irrigated. (author)

Production of greenhouse-grown biocrust mosses and associated cyanobacteria to rehabilitate dryland soil function

Science.gov (United States)

Antoninka, Anita; Bowker, Matthew A.; Reed, Sasha C.; Doherty, Kyle

2016-01-01

Mosses are an often-overlooked component of dryland ecosystems, yet they are common members of biological soil crust communities (biocrusts) and provide key ecosystem services, including soil stabilization, water retention, carbon fixation, and housing of N2 fixing cyanobacteria. Mosses are able to survive long dry periods, respond rapidly to precipitation, and reproduce vegetatively. With these qualities, dryland mosses have the potential to be an excellent dryland restoration material. Unfortunately, dryland mosses are often slow growing in nature, and ex situ cultivation methods are needed to enhance their utility. Our goal was to determine how to rapidly produce, vegetatively, Syntrichia caninervis and S. ruralis, common and abundant moss species in drylands of North America and elsewhere, in a greenhouse. We manipulated the length of hydration on a weekly schedule (5, 4, 3, or 2 days continuous hydration per week), crossed with fertilization (once at the beginning, monthly, biweekly, or not at all). Moss biomass increased sixfold for both species in 4 months, an increase that would require years under dryland field conditions. Both moss species preferred short hydration and monthly fertilizer. Remarkably, we also unintentionally cultured a variety of other important biocrust organisms, including cyanobacteria and lichens. In only 6 months, we produced functionally mature biocrusts, as evidenced by high productivity and ecosystem-relevant levels of N2 fixation. Our results suggest that biocrust mosses might be the ideal candidate for biocrust cultivation for restoration purposes. With optimization, these methods are the first step in developing a moss-based biocrust rehabilitation technology.

Uncertainty assessment of a polygon database of soil organic carbon for greenhouse gas reporting in Canada’s Arctic and sub-arctic

Directory of Open Access Journals (Sweden)

M.F. Hossain

2014-08-01

Full Text Available Canada’s Arctic and sub-arctic consist 46% of Canada’s landmass and contain 45% of the total soil organic carbon (SOC. Pronounced climate warming and increasing human disturbances could induce the release of this SOC to the atmosphere as greenhouse gases. Canada is committed to estimating and reporting the greenhouse gases emissions and removals induced by land use change in the Arctic and sub-arctic. To assess the uncertainty of the estimate, we compiled a site-measured SOC database for Canada’s north, and used it to compare with a polygon database, that will be used for estimating SOC for the UNFCCC reporting. In 10 polygons where 3 or more measured sites were well located in each polygon, the site-averaged SOC content agreed with the polygon data within ±33% for the top 30 cm and within ±50% for the top 1 m soil. If we directly compared the SOC of the 382 measured sites with the polygon mean SOC, there was poor agreement: The relative error was less than 50% at 40% of the sites, and less than 100% at 68% of the sites. The relative errors were more than 400% at 10% of the sites. These comparisons indicate that the polygon database is too coarse to represent the SOC conditions for individual sites. The difference is close to the uncertainty range for reporting. The spatial database could be improved by relating site and polygon SOC data with more easily observable surface features that can be identified and derived from remote sensing imagery.

Influence of spatially dependent, modeled soil carbon emission factors on life-cycle greenhouse gas emissions of corn and cellulosic ethanol

Energy Technology Data Exchange (ETDEWEB)

Qin, Zhangcai [Energy Systems Division, Argonne National Laboratory, 9700 South Cass Avenue Argonne IL 60439 USA; Dunn, Jennifer B. [Energy Systems Division, Argonne National Laboratory, 9700 South Cass Avenue Argonne IL 60439 USA; Kwon, Hoyoung [Environment and Production Technology Division, International Food Policy Research Institute, 2033 K St. NW Washington DC 20006 USA; Mueller, Steffen [Energy Resources Center, University of Illinois at Chicago, 1309 South Halsted Street Chicago IL 60607 USA; Wander, Michelle M. [Department of Natural Resources and Environmental Sciences, University of Illinois at Urbana-Champaign, 1102 South Goodwin Avenue Urbana IL 61801 USA

2016-03-03

Converting land to biofuel feedstock production incurs changes in soil organic carbon (SOC) that can influence biofuel life-cycle greenhouse gas (GHG) emissions. Estimates of these land use change (LUC) and life-cycle GHG emissions affect biofuels’ attractiveness and eligibility under a number of renewable fuel policies in the U.S. and abroad. Modeling was used to refine the spatial resolution and depth-extent of domestic estimates of SOC change for land (cropland, cropland pasture, grasslands, and forests) conversion scenarios to biofuel crops (corn, corn stover, switchgrass, Miscanthus, poplar, and willow). In most regions, conversions from cropland and cropland pasture to biofuel crops led to neutral or small levels of SOC sequestration, while conversion of grassland and forest generally caused net SOC loss. Results of SOC change were incorporated into the Greenhouse Gases, Regulated Emissions, and Energy use in Transportation (GREET) model to assess their influence on life-cycle GHG emissions for the biofuels considered. Total LUC GHG emissions (g CO2eq MJ-1) were 2.1–9.3 for corn, -0.7 for corn stover, -3.4–12.9 for switchgrass, and -20.1–-6.2 for Miscanthus; these varied with SOC modeling assumptions applied. Extending soil depth from 30 to 100cm affected spatially-explicit SOC change and overall LUC GHG emissions; however the influence on LUC GHG emissions estimates were less significant in corn and corn stover than cellulosic feedstocks. Total life-cycle GHG emissions (g CO2eq MJ-1, 100cm) were estimated to be 59–66 for corn ethanol, 14 for stover ethanol, 18-26 for switchgrass ethanol, and -0.6–-7 for Miscanthus ethanol.

NASA Soil Moisture Active Passive (SMAP) Applications

Science.gov (United States)

Orr, Barron; Moran, M. Susan; Escobar, Vanessa; Brown, Molly E.

2014-05-01

The launch of the NASA Soil Moisture Active Passive (SMAP) mission in 2014 will provide global soil moisture and freeze-thaw measurements at moderate resolution (9 km) with latency as short as 24 hours. The resolution, latency and global coverage of SMAP products will enable new applications in the fields of weather, climate, drought, flood, agricultural production, human health and national security. To prepare for launch, the SMAP mission has engaged more than 25 Early Adopters. Early Adopters are users who have a need for SMAP-like soil moisture or freeze-thaw data, and who agreed to apply their own resources to demonstrate the utility of SMAP data for their particular system or model. In turn, the SMAP mission agreed to provide Early Adopters with simulated SMAP data products and pre-launch calibration and validation data from SMAP field campaigns, modeling, and synergistic studies. The applied research underway by Early Adopters has provided fundamental knowledge of how SMAP data products can be scaled and integrated into users' policy, business and management activities to improve decision-making efforts. This presentation will cover SMAP applications including weather and climate forecasting, vehicle mobility estimation, quantification of greenhouse gas emissions, management of urban potable water supply, and prediction of crop yield. The presentation will end with a discussion of potential international applications with focus on the ESA/CEOS TIGER Initiative entitled "looking for water in Africa", the United Nations (UN) Convention to Combat Desertification (UNCCD) which carries a specific mandate focused on Africa, the UN Framework Convention on Climate Change (UNFCCC) which lists soil moisture as an Essential Climate Variable (ECV), and the UN Food and Agriculture Organization (FAO) which reported a food and nutrition crisis in the Sahel.

Soil carbon 4 per mille

NARCIS (Netherlands)

Mulder, V.L.

2017-01-01

The ‘4 per mille Soils for Food Security and Climate’ was launched at the COP21 with an aspiration to increase global soil organic matter stocks by 4 per 1000 (or 0.4 %) per year as a compensation for the global emissions of greenhouse gases by anthropogenic sources. This paper surveyed the soil

Arsenic Accumulation by Pteris vittata L. in Two Chemically Variant Soils Treated with Arsenical Pesticides - Greenhouse Study

Science.gov (United States)

Therapong, C.; Datta, R.; Sarkar, D.; Pachanoor, D.

2006-05-01

Arsenic (As) is one of the most toxic elements present in the environment. Over the years, arsenic has found its way to the environment due to its extensive use in agriculture and in industrial practices as pesticides, fertilizers, wood preservatives, smelter wastes and coal combustion ash, all of which are of great environmental concern. Arsenic contamination affects biological activities because it is a carcinogen and a mutagen, which has detrimental effects on the immune system of animals. Remediation of arsenic-contaminated soils has become a major environmental issue in the recent years. Several physical and chemical treatment methods, such as soil washing, co-precipitation, and excavation, have used to remediate As, but all of these methods are rather expensive and can disturb soil physiology and ecology. Phytoremediation, a plant based technology for the removal of toxic contaminants from soil and water is an attractive approach. Of late, this technology has received a high degree of attention from the scientific community because it is environment-friendly and also because of its tremendous cost efficiency compared to the conventional methods. Chinese Brake Fern (Pteris vittata L.) is a known arsenic hyperaccumulator that is being used extensively at present to remove As from soils. However, the degree of efficiency of this plant in accumulating As is likely to be a function of the soil properties. The objective of the reported study was to investigate arsenic uptake by Chinese Brake Fern in As-contaminated soils from the Immokalee (acid sand with minimal As-retention potential) and Millhopper series (sandy loam with high Fe/Al content, hence, high As-retention potential). A greenhouse experiment was designed to evaluate the effects on As uptake by Chinese Brake Fern at two pesticide application rates: 225 mg/kg and 500 mg/kg As in two chemical forms, namely sodium arsenate (AsV) and dimethylarsinic acid (DMA). Each treatment was replicated three times in

Exposure to methyl bromide during greenhouse fumigation on Crete, Greece

NARCIS (Netherlands)

Vreede, J.A.F. de; Boeft, J. den; Hemmen, J.J. van

1998-01-01

In agricultural areas where greenhouses and dwellings are intermixed, the general population as well as the professional applicators may be exposed to pesticides. In a field study on Crete, exposure to methyl bromide during soil fumigation was assessed. Exposure of applicators (both contractors and

Greenhouse effect of chlorofluorocarbons and other trace gases

Science.gov (United States)

Hansen, James; Lacis, Andrew; Prather, Michael

1989-01-01

A comparison is made of the radiative (greenhouse) forcing of the climate system due to changes of atmospheric chlorofluorocarbons and other trace gases. It is found that CFCs, defined to include chlorofluorocarbons, chlorocarbons, and fluorocarbons, now provide about one-quater of current annual increases in anthropogenic greenhouse climate forcing. If the growth rates of CFC production in the early 1970s had continued to the present, current annual growth of climate forcing due to CFCs would exceed that due to CO2.

Solarization soil

International Nuclear Information System (INIS)

Abou Ghraibe, W.

1995-01-01

Solar energy could be used in pest control, in soil sterilization technology. The technique consists of covering humid soils by plastic films steadily fixed to the soil. Timing must be in summer during 4-8 weeks, where soil temperature increases to degrees high enough to control pests or to produce biological and chemical changes. The technique could be applied on many pests soil, mainly fungi, bacteria, nematods, weeds and pest insects. The technique could be used in greenhouses as well as in plastic film covers or in orchards where plastic films present double benefits: soil sterilization and production of black mulch. Mechanism of soil solarization is explained. Results show that soil solarization can be used in pest control after fruit crops cultivation and could be a method for an integrated pest control. 9 refs

Water utilization of vegetables grown under plastic greenhouse conditions in Ankara using neutron probe technique

International Nuclear Information System (INIS)

Halitligil, M.B.; Kislal, H.; Sirin, H.; Sirin, C.; Kilicaslan, A.

2004-01-01

In order to find suitable varieties of tomato, pepper and cucumber for plastic greenhouse conditions in Ankara and ensure both higher yields and lower NO 3 leaching greenhouse experiments were conducted for three years. In the first year (2001) of the experiment four different varieties from each vegetable, namely, Tomato (Ecem F 1 , 9920 F 1 , 2116 F 1 and Yazg1 F 1 ), Cucumber (Hizir F 1 , Rapido, Hana, and Luna) and Pepper (1245 F 1 , 730 F 1 , Serademre 8 and 710 F 1 ) had been grown in the plastic greenhouse using drip irrigation-fertilization system. Yazg1 F 1 variety for tomato, Hizir F 1 variety for cucumber and Serademre 8 variety for pepper were chosen to be suitable varieties to grow in the plastic greenhouse conditions in Ankara. One access tube in each N 3 and N 0 treatment plots of tomato, cucumber and pepper in 2002 and 2003 experiments were installed for the soil moisture determinations at 30, 60 and 90 cm depths. Readings with the neutron probe were taken before planting and after harvest for the water consumption calculations using the water balance approach and the WUE was calculated on the basis of the ratio of dry matter weight to the amount of water consumed. Tensiometer and suction cups were installed at 15, 30, 45 and 60 cm depths only to N 1 , N 2 and N 3 treatments plots of each vegetable in 2002 and 2003. Tensiometer readings were taken just before irrigation. Also, soil solution samples from suction cups were taken at final harvest and NO 3 determinations were done with RQFLEX nitrate test strips. Significantly higher yields and WUE values were obtained when the same amount of N fertilizer is applied through fertigation compared to the treatment where N fertilizer applied to the soil then drip irrigated. The nitrate concentrations of the soil solution increased as the N rates increased and no NO 3 had been found in the soil solution taken from 75 cm soil depth, indicating that no leaching of N fertilizer occurred beyond 75 cm soil depth

Water utilization of vegetables grown under plastic greenhouse conditions in Ankara using neutron probe technique

International Nuclear Information System (INIS)

Halitligil, M.B.; Kislal, H.; Sirin, H.; Sirin, C.; Kilicaslan, A.

2004-01-01

Full text: In order to find suitable varieties of tomato, pepper and cucumber for plastic greenhouse conditions in Ankara and ensure both higher yields and lower NO 3 leaching greenhouse experiments were conducted for three years. In the first year (2001) of the experiment four different varieties from each vegetable, namely, Tomato (Ecem F 1 , 9920 F 1 , 2116 F 1 and Yazg1 F 1 ), Cucumber (Hizir F 1 , Rapido, Hana, and Luna) and Pepper (1245 F 1 , 730 F 1 , Serademre 8 and 710 F 1 ) had been grown in the plastic greenhouse using drip irrigation-fertiligation system. Yazg1 F 1 variety for tomato, Hizir F 1 variety for cucumber and Serademre 8 variety for pepper were chosen to be suitable varieties to grow in the plastic greenhouse conditions in Ankara. One access tube in each N 3 and N 0 treatment plots of tomato, cucumber and pepper in 2002 and 2003 experiments were installed for the soil moisture determinations at 30, 60 and 90 cm depths. Readings with the neutron probe were taken before planting and after harvest for the water consumption calculations using the water balance approach and the WUE was calculated on the basis of the ratio of dry matter weight to the amount of water consumed. Tensiometer and suction cups were installed at 15, 30, 45 and 60 cm depths only to N 1 , N 2 and N 3 treatments plots of each vegetable in 2002 and 2003. Tensiometer readings were taken just before irrigation. Also, soil solution samples from suction cups were taken at final harvest and NO 3 determinations were done with RQFLEX nitrate test strips. Significantly higher yields and WUE values were obtained when the same amount of N fertilizer is applied through fertigation compared to the treatment where N fertilizer applied to the soil then drip irrigated. The nitrate concentrations of the soil solution increased as the N rates increased and no NO 3 had been found in the soil solution taken from 75 cm soil depth, indicating that no leaching of N fertilizer occurred beyond 75 cm

Sonic anemometry measurements to determine airflow patterns in multi-tunnel greenhouse

Energy Technology Data Exchange (ETDEWEB)

Lopez, A.; Valera, D. L.; Molina-aiz, F. D.; Pena, A.

2012-11-01

The present work describes a methodology for studying natural ventilation in Mediterranean greenhouses using sonic anemometry. The experimental work took place in the three-span greenhouse located at the agricultural research farm belonging to the University of Almeria. This methodology has allowed us to obtain patterns of natural ventilation of the experimental greenhouse under the most common wind regimes for this region. It has also enabled us to describe how the wind and thermal effects interact in the natural ventilation of the greenhouse, as well as to detect deficiencies in the ventilation of the greenhouse, caused by the barrier effect of the adjacent greenhouse (imply a mean reduction in air velocity close to the greenhouse when facing windward of 98% for u, 63% for u, and more importantly 88% for ux, the component of air velocity that is perpendicular to the side vent). Their knowledge allows us to improve the current control algorithms that manage the movement of the vents. In this work we make a series of proposals that could substantially improve the natural ventilation of the experimental greenhouse. For instance, install vents equipped with ailerons which guide the air inside, or with vents in which the screen is not placed directly over the side surface of the greenhouse. A different proposal is to prolong the opening of the side vents down to the soil, thus fomenting the entrance of air at crop level. (Author) 34 refs.

[Preliminary assessment of the potential of biochar technology in mitigating the greenhouse effect in China].

Science.gov (United States)

Jiang, Zhi-Xiang; Zheng, Hao; Li, Feng-Min; Wang, Zhen-Yu

2013-06-01

The production of biochar by pyrolysis and its application to soil can sequester the CO2 which was absorbed by plants from atmosphere into soil, in addition it can also bring multiple benefits for agriculture production. On the basis of the available potential survey of the biomass residues from agriculture and forestry section, life cycle assessment was employed to quantify the potential of biochar technology in mitigation of greenhouse gases in our country. The results showed: In China, the amount of available biomass resource was 6.04 x 10(8) t every year and its net greenhouse effect potential was 5.32 x 10(8) t CO(2e) (CO(2e): CO2 equivalent), which was equivalent to 0.88 t CO(2e) for every ton biomass. The greatest of contributor to the total potential was plant carbon sequestration in soil as the form of biochar which accounts for 73.94%, followed by production of renewable energy and its percentage was 23.85%. In summary, production of biochar from agriculture and forestry biomass residues had a significant potential for our country to struggle with the pressure of greenhouse gas emission.

Impact of water quality and irrigation management on organic greenhouse horticulture

NARCIS (Netherlands)

Dorais, M.; Alsanius, B.W.; Voogt, W.; Pepin, S.; Tuzel, Hakki; Tuzel, Yuksel; Möller, Kurt

2016-01-01

Water quality and water supply are essential for organic greenhouse grown crops to prevent soil contamination by undesirable chemicals and microorganisms, while providing the correct amount of water required for plant growth. The absence of natural precipitation combined with higher

Probabilistic risk assessment of nitrate groundwater contamination from greenhouses in Albenga plain (Liguria, Italy) using lysimeters.

Science.gov (United States)

Paladino, Ombretta; Seyedsalehi, Mahdi; Massabò, Marco

2018-04-05

The use of fertilizers in greenhouse-grown crops can pose a threat to groundwater quality and, consequently, to human beings and subterranean ecosystem, where intensive farming produces pollutants leaching. Albenga plain (Liguria, Italy) is an alluvial area of about 45km 2 historically devoted to farming. Recently the crops have evolved to greenhouses horticulture and floriculture production. In the area high levels of nitrates in groundwater have been detected. Lysimeters with three types of reconstituted soils (loamy sand, sandy clay loam and sandy loam) collected from different areas of Albenga plain were used in this study to evaluate the leaching loss of nitrate (NO 3 - ) over a period of 12weeks. Leaf lettuce (Lactuca sativa L.) was selected as a representative green-grown crop. Each of the soil samples was treated with a slow release fertilizer, simulating the real fertilizing strategy of the tillage. In order to estimate the potential risk for aquifers as well as for organisms exposed via pore water, nitrate concentrations in groundwater were evaluated by applying a simplified attenuation model to the experimental data. Results were refined and extended from comparison of single effects and exposure values (Tier I level) up to the evaluation of probabilistic distributions of exposure and related effects (Tier II, III IV levels). HHRA suggested HI >1 and about 20% probability of exceeding RfD for all the greenhouses, regardless of the soil. ERA suggested HQ>100 for all the greenhouses; 93% probability of PNEC exceedance for greenhouses containing sand clay loam. The probability of exceeding LC50 for 5% of the species was about 40% and the probability corresponding to DBQ of DEC/EC50>0.001 was >90% for all the greenhouses. The significantly high risk, related to the detected nitrate leaching loss, can be attributed to excessive and inappropriate fertigation strategies. Copyright © 2018 Elsevier B.V. All rights reserved.

Assessing the Efficiency of Phenotyping Early Traits in a Greenhouse Automated Platform for Predicting Drought Tolerance of Soybean in the Field.

Science.gov (United States)

Peirone, Laura S; Pereyra Irujo, Gustavo A; Bolton, Alejandro; Erreguerena, Ignacio; Aguirrezábal, Luis A N

2018-01-01

Conventional field phenotyping for drought tolerance, the most important factor limiting yield at a global scale, is labor-intensive and time-consuming. Automated greenhouse platforms can increase the precision and throughput of plant phenotyping and contribute to a faster release of drought tolerant varieties. The aim of this work was to establish a framework of analysis to identify early traits which could be efficiently measured in a greenhouse automated phenotyping platform, for predicting the drought tolerance of field grown soybean genotypes. A group of genotypes was evaluated, which showed variation in their drought susceptibility index (DSI) for final biomass and leaf area. A large number of traits were measured before and after the onset of a water deficit treatment, which were analyzed under several criteria: the significance of the regression with the DSI, phenotyping cost, earliness, and repeatability. The most efficient trait was found to be transpiration efficiency measured at 13 days after emergence. This trait was further tested in a second experiment with different water deficit intensities, and validated using a different set of genotypes against field data from a trial network in a third experiment. The framework applied in this work for assessing traits under different criteria could be helpful for selecting those most efficient for automated phenotyping.

Assessing the Efficiency of Phenotyping Early Traits in a Greenhouse Automated Platform for Predicting Drought Tolerance of Soybean in the Field

Directory of Open Access Journals (Sweden)

Laura S. Peirone

2018-05-01

Full Text Available Conventional field phenotyping for drought tolerance, the most important factor limiting yield at a global scale, is labor-intensive and time-consuming. Automated greenhouse platforms can increase the precision and throughput of plant phenotyping and contribute to a faster release of drought tolerant varieties. The aim of this work was to establish a framework of analysis to identify early traits which could be efficiently measured in a greenhouse automated phenotyping platform, for predicting the drought tolerance of field grown soybean genotypes. A group of genotypes was evaluated, which showed variation in their drought susceptibility index (DSI for final biomass and leaf area. A large number of traits were measured before and after the onset of a water deficit treatment, which were analyzed under several criteria: the significance of the regression with the DSI, phenotyping cost, earliness, and repeatability. The most efficient trait was found to be transpiration efficiency measured at 13 days after emergence. This trait was further tested in a second experiment with different water deficit intensities, and validated using a different set of genotypes against field data from a trial network in a third experiment. The framework applied in this work for assessing traits under different criteria could be helpful for selecting those most efficient for automated phenotyping.

Screening identification of aerobic denitrification bacteria with high soil desalinization capacity

Science.gov (United States)

Jin, H.; Chen, H.; Jin, H.; Qian, Y.; Zhang, K.

2017-08-01

In order to study the mechanism of bacteria used in the saline soil remediation process, the aerobic denitrification bacteria were isolated from an agricultural greenhouse soil in a farm in East China’s Zhejiang Province. The identification, nitrogen reducing characteristics and the denitrification effect of bacteria from different soils at various locations were investigated. The results showed that the NO3- removal rate was 91% with bacteria from the greenhouse soil under aerobic conditions in 52 h, and the bacteria were identified as Gram-positive Castellaniella denitrification bacteria.

Fungal decomposition of terrestrial organic matter accelerated Early Jurassic climate warming

Science.gov (United States)

Pieńkowski, Grzegorz; Hodbod, Marta; Ullmann, Clemens V.

2016-08-01

Soils - constituting the largest terrestrial carbon pool - are vulnerable to climatic warming. Currently existing uncertainties regarding carbon fluxes within terrestrial systems can be addressed by studies of past carbon cycle dynamics and related climate change recorded in sedimentary successions. Here we show an example from the Early Jurassic (early Toarcian, c. 183 mya) marginal-marine strata from Poland, tracking the hinterland response to climatic changes through a super-greenhouse event. In contrast to anoxia-related enhanced carbon storage in coeval open marine environments, Total Organic Carbon (TOC) concentrations in the Polish successions are substantially reduced during this event. Increasing temperature favoured fungal-mediated decomposition of plant litter - specifically of normally resistant woody tissues. The associated injection of oxidized organic matter into the atmosphere corresponds to abrupt changes in standing vegetation and may have contributed significantly to the amplified greenhouse climate on Earth. The characteristic Toarcian signature of multiple warm pulses coinciding with rapidly decreasing carbon isotope ratios may in part be the result of a radical reduction of the terrestrial carbon pool as a response to climate change.

Effect of greenhouse vegetable farming duration on Zinc accumulation in Northeast China

Science.gov (United States)

Wang, Jun; Yu, Peiying; Cui, Shuang; Chen, Xin; Shi, Yi

2018-02-01

Greenhouse vegetable production (GVP) has rapidly expanded, and reqiures more attention due to its heavy metal contamination. In this study, different cultivation greenhouses of 1, 2, 3, 5 and 13 years were selected to investigate the effects of GVP duration on Zn accumulation. The results revealed high Zn (total Zn and available Zn) accumulation in GVP surface layers (0-20 cm), and Zn contents in 0-20 cm soil layers were positively correlated with GVP duration (P<0.01). Zn accumulation was mainly attributed to manure fertilizer application due to higher concentrations of Zn in manures. For greenhouse sustainability, reduction of manure application and reasonable use of passivation materials may alleviate metal phytoavailability and the health risk.

Denitrification capacity and greenhouse gas emissions of soils in channelized and restored reaches along an Alpine river corridor

Science.gov (United States)

Shrestha, Juna; Niklaus, Pascal; Samaritani, Emanuela; Frossard, Emmanuel; Tockner, Klement; Luster, Jörg

2010-05-01

In order to assess the effects of river restoration on water and air quality, the biogeochemical functions of channelized and restored river reaches have to be quantified. The objective of this study was to compare denitrification potential and greenhouse gas emissions of functional processing zones (FPZ) in a channelized and a recently restored reach of the alpine river Thur in north-eastern Switzerland. The study was part of the project cluster RECORD of the ETH domain, Switzerland, which was initiated to increase the mechanistic understanding of coupled hydrological and ecological processes in river corridors. The denitrification potential represents an important aspect of the soil filter function related to water quality. Besides, it also contributes to the emission of greenhouse gases. Extensively used pasture growing on a sandy loam is the characteristic FPZ of the channelized section. The restored section encompasses five FPZ: (i) bare gravel bars sparsely colonized by plants, (ii) gravel bars densely colonized by grass (mainly canary reed grass with up to 80 cm sandy deposits), (iii) mixed forest dominated by ash and maple, (iv) riparian forest dominated by willow (Salix alba), (v) older overbank sediments stabilized during restoration with young willows separating the forests from the river-gravel bar system (willow bush). The FPZ were sampled in January, April, August and October 2009. In addition, in June and July 2009 two flood events were monitored in the restored section with more frequent samplings. At each date, topsoil samples were collected in each FPZ (four replicates per samples) and analyzed for denitrifier enzyme activity (DEA). In addition, gas samples were taken in-situ using the closed chamber technique to measure soil respiration as well as N2O and CH4 fluxes. In all FPZ, the denitrification potential was mainly governed by soil moisture. It was highest in the willow forest exhibiting low spatial variability. The DEA in pasture, grass zone

Effect of reed canary grass cultivation on greenhouse gas emission from peat soil at controlled rewetting

DEFF Research Database (Denmark)

Karki, Sandhya; Elsgaard, Lars; Lærke, Poul Erik

2015-01-01

Cultivation of bioenergy crops in rewetted peatland (paludiculture) is considered as a possible land use option to mitigate greenhouse gas (GHG) emissions. However, bioenergy crops like reed canary grass (RCG) can have a complex influence on GHG fluxes. Here we determined the effect of RCG...... and bare soil were measured at weekly to fortnightly intervals with static chamber techniques for a period of 1 year. Cultivation of RCG increased both ER and CH4 emissions, but decreased the N2O emissions. The presence of RCG gave rise to 69, 75 and 85% of total ER at −20, −10 and 0 cm GWL, respectively...... from ER were obviously the dominant RCG-derived GHG flux, but above-ground biomass yields, and preliminary measurements of gross photosynthetic production, showed that ER could be more than balanced due to the photosynthetic uptake of CO2 by RCG. Our results support that RCG cultivation could be a good...

Effect of Soil Tillage Practices on Dynamic of Bacterial Communities in Soil

OpenAIRE

Mirna Mrkonjić Fuka; Mihaela Blažinkov; Viviane Radl; Danijel Jug; Nataša Hulak; Sulejman Redžepović; Michael Schloter

2016-01-01

Several studies have indicated that intensive tillage has notable effect on properties of the soil microbiota that may influence numerous important soils functions, e.g. mobilization of nutrients or change of the overall emission rates of greenhouse gases. Therefore, the aim of our study was to investigate dynamic of microbial communities in soil planted with soybean under different tillage systems. Moreover, abundance of populations harboring the nitrous- oxide reductase gene (nosZ) a...

Emission of greenhouse gases and soil carbon sequestration in a riparian marsh wetland in central Ohio.

Science.gov (United States)

Nag, Subir K; Liu, Ruiqiang; Lal, Rattan

2017-10-23

Wetlands are a C sink, but they also account for a large natural source of greenhouse gases (GHG), particularly methane (CH 4 ). Soils of wetlands play an important role in alleviating the global climate change regardless of the emission of CH 4 . However, there are uncertainties about the amount of C stored and emitted from wetlands because of the site specific factors. Therefore, the present study was conducted in a temperate riverine flow-through wetland, part of which was covered with emerging macrophyte Typhus latifolia in central Ohio, USA, with the objective to assess emissions of GHGs (CH 4, CO 2 , N 2 O) and measure C and nitrogen (N) stocks in wetland soil in comparison to a reference upland site. The data revealed that CH 4 emission from the open and vegetated wetland ranged from 1.03-0.51 Mg C/ha/y and that of CO 2 varied from 1.26-1.51 Mg C/ha/y. In comparison, CH 4 emission from reference upland site was negligible (0.01 Mg C/ha/y), but CO 2 emission was much higher (3.24 Mg C/ha/y). The stock of C in wetland soil was 85 to 125 Mg C/ha up to 0.3 m depth. The average rate of emission was 2.15 Mg C/ha/y, but the rate of sequestration was calculated as 5.55 Mg C/ha/y. Thus, the wetland was actually a C sink. Emission of N 2 O was slightly higher in vegetated wetland (0.153 mg N 2 O-N/m 2 /h) than the open wetland and the reference site (0.129 mg N 2 O-N/m 2 /h). Effect of temperature on emission of GHGs from the systems was also studied.

A blue carbon soil database: Tidal wetland stocks for the US National Greenhouse Gas Inventory

Science.gov (United States)

Feagin, R. A.; Eriksson, M.; Hinson, A.; Najjar, R. G.; Kroeger, K. D.; Herrmann, M.; Holmquist, J. R.; Windham-Myers, L.; MacDonald, G. M.; Brown, L. N.; Bianchi, T. S.

2015-12-01

Coastal wetlands contain large reservoirs of carbon, and in 2015 the US National Greenhouse Gas Inventory began the work of placing blue carbon within the national regulatory context. The potential value of a wetland carbon stock, in relation to its location, soon could be influential in determining governmental policy and management activities, or in stimulating market-based CO2 sequestration projects. To meet the national need for high-resolution maps, a blue carbon stock database was developed linking National Wetlands Inventory datasets with the USDA Soil Survey Geographic Database. Users of the database can identify the economic potential for carbon conservation or restoration projects within specific estuarine basins, states, wetland types, physical parameters, and land management activities. The database is geared towards both national-level assessments and local-level inquiries. Spatial analysis of the stocks show high variance within individual estuarine basins, largely dependent on geomorphic position on the landscape, though there are continental scale trends to the carbon distribution as well. Future plans including linking this database with a sedimentary accretion database to predict carbon flux in US tidal wetlands.

Recuperação de um solo salinizado após cultivo em ambiente protegido Reclamation of a salinized soil after cultivation in greenhouse

Directory of Open Access Journals (Sweden)

Flávio F. Blanco

2001-04-01

Full Text Available O excesso de fertilizantes e o manejo inadequado da irrigação nos cultivos em ambiente protegido, têm levado à salinização dos solos, o que resulta na redução da produtividade das culturas. O objetivo deste trabalho foi avaliar diferentes lâminas de lavagem e métodos de aplicação na recuperação de um solo salinizado em ambiente protegido. Foram utilizadas três diferentes frações (2/3, 1 e 3/2 da lâmina calculada, aplicadas por gotejamento e inundação, resultando em um esquema fatorial 2 x 3, com três repetições. Pelos resultados obtidos, concluiu-se que a aplicação por gotejamento foi mais eficiente na lixiviação dos sais acumulados no solo, devendo-se utilizar lâmina relativa de lavagem e coeficiente k de 0,9 e 0,1 para gotejamento e de 1,3 e 0,2 para inundação, respectivamente.Overapplication of fertilizers and inadequate irrigation management in greenhouse crops have caused soil salinization, resulting in reduction of crop yields. The aim of this work was to evaluate different depths of leaching and methods of application for reclamation of a salinized soil under greenhouse conditions. Three relative water depths (2/3, 1, 3/2, based on calculated leaching water depth, were applied by drip irrigation and flooding, in a 2 x 3 factorial scheme, with 3 replications. From the obtained results, it may be concluded that the application by drip was more efficient than flooding in leaching the accumulated salts in the soil and the relative water depth and coefficient k of 0.9 and 0.1 for drip and 1.3 and 0.2 for flooding, respectively, should be used.

Summer fluxes of atmospheric greenhouse gases N{sub 2}O, CH{sub 4} and CO{sub 2} from mangrove soil in South China

Energy Technology Data Exchange (ETDEWEB)

Chen, G.C. [Department of Biology and Chemistry, City University of Hong Kong, Hong Kong SAR (China); Tam, N.F.Y., E-mail: bhntam@cityu.edu.hk [Department of Biology and Chemistry, City University of Hong Kong, Hong Kong SAR (China); Ye, Y. [State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, Fujian (China)

2010-06-01

The atmospheric fluxes of N{sub 2}O, CH{sub 4} and CO{sub 2} from the soil in four mangrove swamps in Shenzhen and Hong Kong, South China were investigated in the summer of 2008. The fluxes ranged from 0.14 to 23.83 {mu}mol m{sup -2} h{sup -1}, 11.9 to 5168.6 {mu}mol m{sup -2} h{sup -1} and 0.69 to 20.56 mmol m{sup -2} h{sup -1} for N{sub 2}O, CH{sub 4} and CO{sub 2}, respectively. Futian mangrove swamp in Shenzhen had the highest greenhouse gas fluxes, followed by Mai Po mangrove in Hong Kong. Sha Kong Tsuen and Yung Shue O mangroves in Hong Kong had similar, low fluxes. The differences in both N{sub 2}O and CH{sub 4} fluxes among different tidal positions, the landward, seaward and bare mudflat, in each swamp were insignificant. The N{sub 2}O and CO{sub 2} fluxes were positively correlated with the soil organic carbon, total nitrogen, total phosphate, total iron and NH{sub 4}{sup +}-N contents, as well as the soil porosity. However, only soil NH{sub 4}{sup +}-N concentration had significant effects on CH{sub 4} fluxes.

A study of indoor radon in greenhouses in Mexico City, Mexico

International Nuclear Information System (INIS)

Guillermo Espinosa; Allan Chavarria; Jose-Ignacio Golzarri

2013-01-01

Enclosed spaces in contact with soil, the main source of radon, like greenhouses have potentially high radon ( 222 Rn) concentrations. Greenhouses are frequented by visitors and also are workplaces. The study of radon concentrations in greenhouses is, thus, a relevant concern for public health and environmental radiation authorities. For this study, the radon concentrations in 12 greenhouses in different locations within Mexico City were measured using nuclear track methodology. The detectors used for the study consisted of the well-known closed-end cup device, with CR-39 Lantrack R as detector material. The measurements were carried out over a period of one year, divided into four three-month sub-periods. The lowest and highest annual mean radon concentrations found in individual greenhouses were 17.0 and 45.1 Bq/m 3 , respectively. The annual mean averaged over all 12 greenhouses was 27.3 Bq/m 3 . No significant seasonal variation was observed. Using the highest annual mean radon concentration found in an individual greenhouse, and an equilibrium factor of 0.4, the effective dose from 222 Rn and its progenies was calculated to be 339.9 nSv/h. This corresponds to an annual dose rate of 679.8 μSv/y (0.057 WLM/y) for a worker spending 4 h a day, 5 days a week, 50 weeks a year, inside the greenhouse. For a visitor spending 12 h a year inside the greenhouse the annual dose is 2.469 μSv/y. The study of indoor radon concentrations in closed buildings such as greenhouses, which are both workplaces and open to visitors, is an important public health consideration. (author)

Lead and cadmium interactions in Cynodon nlemfuensis and sandy soil subjected to treated wastewater application under greenhouse conditions

Science.gov (United States)

Madyiwa, Simon; Chimbari, Moses John; Schutte, Frederik

Pb and Cd are known to influence each other’s uptake by some plants when the two metals exist in the soil in significant amounts. This influence may be beneficial if it reduces uptake of metal by plants but may be detrimental if it increases uptake of the metal. This study was carried out to investigate the interaction of Pb and Cd in sandy soils and Cynodon nlemfluensis (star grass). Star grass was grown under greenhouse conditions in 33 fertilized pots containing sandy soils. Three weeks after planting the grass the pots were randomly assigned to the following treatments replicated three times; (a) application of three varying concentrations of Pb or Cd in addition to effluent and sludge, (b) application of three varying concentrations of combined Pb and Cd in addition to effluent and sludge, (c) application of water and (d) application of only effluent and sludge. Analysis of grass samples was done 45 and 90 days after addition of Pb and Cd to pots and that of the soil was done 90 days after addition of Pb and Cd to pots. The log normal mean level (in mg/kg) of Pb detected in the soil was 1.75 and that of Cd was 0.057 in mixed treatments while for single treatments the levels were 1.67 for Pb and 0.03 for Cd. The presence of Cd in the soil had no effect on the bio-available level of Pb but Pb significantly ( p < 0.05) increased the bio-available concentration of Cd. The log normal mean levels of Pb in grass re-growth from mixed treatment was 1.68 and that of Cd was 0.57 while the values for single treatments were 1.47 for Pb and 0.31 for Cd. There was no significant change in the level of uptake of Pb between single treatments and mixed treatments. However, Pb significantly increased uptake of Cd in mixed treatments compared to single treatments ( p < 0.05). The results of this study indicate that co-presence of Pb and Cd may have the detrimental effect of increasing uptake of Cd in star grass.

Early-season wind erosion influenced by soil-incorporated green manure in the Pacific Northwest

Science.gov (United States)

Management strategies are sought to minimize wind erosion of irrigated agricultural soils along the Columbia River of the Inland Pacific Northwest, particularly during the early season (March-April) when high winds coincide with sowing of vegetable crops. Early-season wind erosion potential from soi...

Metal stress and decreased tree growth in response to biosolids application in greenhouse seedlings and in situ Douglas-fir stands

International Nuclear Information System (INIS)

Cline, Erica T.; Nguyen, Quyen T.N.; Rollins, Lucy; Gawel, James E.

2012-01-01

To assess physiological impacts of biosolids on trees, metal contaminants and phytochelatins were measured in Douglas-fir stands amended with biosolids in 1982. A subsequent greenhouse study compared these same soils to soils amended with fresh wastewater treatment plant biosolids. Biosolids-amended field soils had significantly higher organic matter, lower pH, and elevated metals even after 25 years. In the field study, no beneficial growth effects were detected in biosolids-amended stands and in the greenhouse study both fresh and historic biosolids amendments resulted in lower seedling growth rates. Phytochelatins – bioindicators of intracellular metal stress – were elevated in foliage of biosolids-amended stands, and significantly higher in roots of seedlings grown with fresh biosolids. These results demonstrate that biosolids amendments have short- and long-term negative effects that may counteract the expected tree growth benefits. - Highlights: ► Biosolids amendment increases soil metals over 25 years later. ► Douglas-fir growth benefits fail to materialize from biosolids amendments. ► Phytochelatins are elevated in foliage of trees and roots of greenhouse seedlings after new biosolids are added to soil. ► Biosolids connected to metal stress in Douglas-fir. - Biosolids applications increase bioindicators of intracellular metal stress and may counteract tree growth benefits.

Contribution to the fight against the greenhouse effect carbon storage in the agricultural soils in France. A collective scientific expertise realized by the INRA for the Ministry of the Ecology and the sustainable development 15 january 2003

International Nuclear Information System (INIS)

2003-01-01

The expertise realized by the INRA relatives the interest of storage carbon in agricultural soils in France: if the possibility of storage is not inconsiderable, its valorization in the framework of the Kyoto protocol is difficult. This storage should be considered in a broader framework, including all the greenhouse gases and integrated in a global plan on the sustainable agriculture and soils quality. (A.L.B.)

Greenhouse Gases

Science.gov (United States)

... Production of Hydrogen Use of Hydrogen Greenhouse Gases Basics | | Did you know? Without naturally occurring greenhouse gases, the earth would be too cold to support life as we know it. Without the greenhouse effect, ...

Soil friability - Concept, Assessment and Effects of Soil Properties and Management

DEFF Research Database (Denmark)

Munkholm, Lars Juhl

Soil friability is a key soil physical property yielding valuable information on the ease of productin a favorable seed- and root beds during tillage operations. Therefore, soil friability is acrucial soil property in relation to the ability of soil to support plant growth and to minimzethe energy...... required for tillage. The topic has interested farmers and soil scientiest for centuries, but is was the paper by Utomo and Dexter (1981) that significantly put the topic on the soil science agenda. The awareness of soil friability is growing, both in practiceand in soil science. This must be viewed...... in the light of the present renewed focus on global food security together with a focus on fossil fuel consumption and greenhouse gas emissions in crop production. Certainly, the demand for well-functioning, arable soils is rising to meet the global challenges....

Residential greenhouse

Energy Technology Data Exchange (ETDEWEB)

1985-02-01

The following report examines the technical and economic viability of residential greenhouse additions in Whitehorse, Yukon. The greenhouse was constructed using the south facing wall of an existing residence as a common wall. Total construction costs were $18,000, including labour. Annual fuel demand for the residence has been reduced by about 10 per cent for an annual saving of $425. In addition, produce to the value of $1,000 is grown annually in the greenhouse for domestic consumption and commercial resale. Typically the greenhouse operates for nine months each year. There is a net thermal loss during the months of November, December and January as a result of the large area of glazing. As well as supplementing the heating supply solar greenhouses can provide additional cash crops which can be used to offset the cost of construction. Humidity problems are minimal and can be dealt with by exhausting high humidity air. One system which has been considered for the greenhouse is to use a standard residential heat pump to remove excess moisture and to pump heat into the house. This would have a secondary benefit of excluding the need to circulate greenhouse air through the house. Thus any allergenic reactions to the greenhouse air would be prevented. 8 refs., 3 figs, 2 tabs.

Precise soil management as a tool to reduce CH4 and N2O emissions from agricultural soils

NARCIS (Netherlands)

Mosquera Losada, J.; Hol, J.M.G.; Rappoldt, C.; Dolfing, J.

2007-01-01

Soil compaction stimulates the emission of nitrous oxide (N2O) and methane (CH4) from agricultural soils. N2O and CH4 are potent greenhouse gases, with a global warming potential respectively 296 times and 23 times greater than CO2.. Agricultural soils are an important source of N2O. Hence there is

Can Tomato Inoculation with Trichoderma Compensate Yield and Soil Health Deficiency due to Soil Salinity?

Science.gov (United States)

Wagner, Karl; Apostolakis, Antonios; Daliakopoulos, Ioannis; Tsanis, Ioannis

2016-04-01

Soil salinity is a major soil degradation threat, especially for arid coastal environments where it hinders agricultural production and soil health. Protected horticultural crops in the Mediterranean region, typically under deficit irrigation and intensive cultivation practices, have to cope with increasing irrigation water and soil salinization. This study quantifies the beneficial effects of the Trichoderma harzianum (TH) on the sustainable production of Solanum lycopersicum (tomato), a major greenhouse crop of the RECARE project Case Study in Greece, the semi-arid coastal Timpaki basin in south-central Crete. 20 vigorous 20-day-old Solanum lycopersicum L. cv Elpida seedlings are treated with TH fungi (T) or without (N) and transplanted into 35 L pots under greenhouse conditions. Use of local planting soil with initial Electrical Conductivity (ECe) 1.8 dS m-1 and local cultivation practices aim to simulate the prevailing conditions at the Case Study. In order to simulate seawater intrusion affected irrigation, plants are drip irrigated with two NaCl treatments: slightly (S) saline (ECw = 1.1 dS m-1) and moderately (M) saline water (ECw = 3.5 dS m-1), resulting to very high and excessively high ECe, respectively. Preliminary analysis of below and aboveground biomass, soil quality, salinity, and biodiversity indicators, suggest that TH pre-inoculation of tomato plants at both S and M treatments improve yield, soil biodiversity and overall soil health.

Radiation and energy balance of lettuce culture inside a polyethylene greenhouse

International Nuclear Information System (INIS)

Frisina, V. de A.; Escobedo, J.F.

1999-01-01

The objective of this paper was to describe the radiation and energy balance, during the lettuce (Lactuca sativa, L. cv. Verônica) crop cycle inside a polyethylene greenhouse. The radiation and energy balance was made inside a tunnel greenhouse with polyethylene cover (100 mm) and in an external area, both areas with 35 m 2 . Global, reflected and net radiation, soil heat flux and air temperature (dry and humid) were measured during the crop cycle. A Datalogger, which operated at 1 Hz frequency, storing 5 minutes averages was utilized. The global (K↓) and reflected (K) radiations showed that the average transmission of global radiation (K↓in / K↓ex) was almost constant, near to 79.59%, while the average ratio of reflected radiation (Kin / Kex) was 69.21% with 8.47% standard-deviation. The normalized curves of short-wave net radiation, in relation to the global radiation (K*/ K↓), found for both environments, were almost constant at the beginning of cycle; this relation decreased in the final stage of culture. The normalized relation (Rn/ K↓) was bigger in the external area, about 12%, when the green culture covered the soil surface. The long-wave radiation balance average (L*) was bigger outside, about 50%. The energy balance, estimated in terms of vertical fluxes, showed that, for the external area, in average, 83.07% of total net radiation was converted in latent heat evaporation (LE), and 18% in soil heat flux (G), and 9.96% in sensible heat (H), while inside of the greenhouse, 58.71% of total net radiation was converted in LE, 42.68% in H, and 28.79% in G. (author) [pt

Plant-soil interactions promote co-occurrence of three nonnative woody shrubs.

Science.gov (United States)

Kuebbing, Sara E; Classen, Aimée T; Call, Jaime J; Henning, Jeremiah A; Simberloff, Daniel

2015-08-01

Ecosystems containing multiple nonnative plant species are common, but mechanisms promoting their co-occurrence are understudied. Plant-soil interactions contribute to the dominance of singleton species in nonnative ranges because many nonnatives experience stronger positive feedbacks relative to co-occurring natives. Plant-soil interactions could impede other nonnatives if an individual nonnative benefits from its soil community to a greater extent than its neighboring nonnatives, as is seen with natives. However, plant-soil interactions could promote nonnative co-occurrence if a nonnative accumulates beneficial soil mutualists that also assist other nonnatives. Here, we use greenhouse and field experiments to ask whether plant-soil interactions (1) promote the codominance of two common nonnative shrubs (Ligustrum sinense and Lonicera maackii) and (2) facilitate the invasion of a less-common nonnative shrub (Rhamnus davurica) in deciduous forests of the southeastern United States. In the greenhouse, we found that two of the nonnatives, L. maackii and R. davurica, performed better in soils conditioned by nonnative shrubs compared to uninvaded forest soils, which. suggests that positive feedbacks among co-occurring nonnative shrubs can promote continued invasion of a site. In both greenhouse and field experiments, we found consistent signals that the codominance of the nonnatives L. sinense and L. maackii may be at least partially explained by the increased growth of L. sinense in L. maackii soils. Overall, significant effects of plant-soil interactions on shrub performance indicate that plant-soil interactions can potentially structure the co-occurrence patterns of these nonnatives.

Occurrence, characterization and management of fruit rot of immature cucumber fruits under arid greenhouse conditions

Directory of Open Access Journals (Sweden)

ABDULLAH M AL-SADI

2012-01-01

Full Text Available A study was undertaken to characterize and manage pathogens associated with fruit rot of immature cucumber fruits in greenhouses in Oman. A survey over 5 growing seasons from 2008 to 2010 in 99 different greenhouses in Oman showed that the disease is prevalent in 91 (92% greenhouses and results in losses of 10 to 60% (avg. 33% of immature fruits per plant. Incidence of the disease was not found to be affected by growing seasons, which could be attributed to the limited fluctuations in ambient temperatures in greenhouses. Isolations from diseased cucumber fruits yielded Alternaria alternata (isolation frequency = 52%, Fusarium equiseti (40%, Cladosporium tenuissium (27%, Botrytis cinerea (6%, Fusarium solani (6%, Corynespora cassiicola (3%, Aspergillus spp. (2%, Curvularia sp. (1% and Bipolaris sp. (1%. With the exception of Curvularia and Bipolaris species, all other fungi were pathogenic on cucumber fruits, with Fusarium equiseti being the most aggressive, followed by Corynespora cassiicola, Botrytis cinerea and Alternaria alternata. Cladosporium and Aspergillus spp. were found to be weakly pathogenic. Comparing the efficacy of foliar and soil applications of carbendazim fungicide on fruit rot of cucumber showed that foliar applications significantly reduced fruit rot and increased cucumber yield when compared to soil application or to control (P < 0.01. This appears to be the first report of the association of Corynespora cassiicola and Fusarium equiseti with fruit rot of immature greenhouse cucumbers. This is also the first report in Oman for the association of Cladosporium tenuissimum with fruit rot of immature cucumbers. Findings are discussed in terms of factors affecting disease control in greenhouses using carbendazim.

Effects of soil and foliar applications of iron and zinc on flowering and essential oil of chamomile at greenhouse conditions

Directory of Open Access Journals (Sweden)

Yousef NASIRI

2015-11-01

Full Text Available In order to study the effects of soil and foliar applications of iron (Fe and zinc (Zn on flowering, flower yield and essential oil production of German chamomile a pot experiment was conducted under greenhouse conditions at the Faculty of Agriculture, University of Tabriz, Iran in 2012. The experiment was arranged as completely randomized design with 12 treatments and three replications. Treatments were as follow: T1: control – without Fe or Zn fertilizers, T2: 30 mg FeSO4.7H2O kg-1 dry soil, T3: 22 mg ZnSO4.7H2O kg-1 dry soil, T4: 30 mg FeSO4.7H2O + 22 mg ZnSO4.7H2O kg-1 dry soil, T5: foliar spraying of FeSO4.7H2O (3.5 g L-1, T6: foliar spraying of FeSO4.7H2O (7.0 g L-1, T7: foliar spraying of ZnSO4.7H2O (2.5 g L-1, T8: foliar spraying of ZnSO4.7H2O (5.0 g L-1, T9: T5+T7, T10: T5+T8, T11: T6+T7, T12: T6+T8. The foliar spraying was done two times during the growing period. The results revealed that the flower number, flower yield, essential oil content and essential oil yield were significantly increased by soil and foliar applications of Fe + Zn, compared with the control (untreated. The highest flower number (477 plant-1, flower yield (11.6 g pot-1, essential oil content (0.88 % and essential oil yield (119 mg pot-1 were recorded for the soil application of Fe + Zn (T4 by 58, 68, 21.4 and 105 % increment compared to the control, respectively. Foliar application of Fe + Zn (T12 was placed at the next rank; however this treatment had no significant difference with the soil application of Fe + Zn (T4. Other treatments did not show significant differences with the control. Generally, the results showed that soil or foliar application of Fe + Zn can be effective on increase or improve of quantity and quality of chamomile yield. Moreover, use of foliar application as a low cost method especially in areas with alkaline or calcareous soils can be recommended.

The history of human-induced soil erosion: Geomorphic legacies, early descriptions and research, and the development of soil conservation—A global synopsis

Science.gov (United States)

Dotterweich, Markus

2013-11-01

This paper presents a global synopsis about the geomorphic evidence of soil erosion in humid and semihumid areas since the beginning of agriculture. Historical documents, starting from ancient records to data from the mid-twentieth century and numerous literature reviews form an extensive assortment of examples that show how soil erosion has been perceived previously by scholars, land surveyors, farmers, land owners, researchers, and policy makers. Examples have been selected from ancient Greek and Roman Times and from central Europe, southern Africa, North America, the Chinese Loess Plateau, Australia, New Zealand, and Easter Island. Furthermore, a comprehensive collection on the development of soil erosion research and soil conservation has been provided, with a particular focus on Germany and the USA. Geomorphic evidence shows that most of the agriculturally used slopes in the Old and New Worlds had already been affected by soil erosion in earlier, prehistoric times. Early descriptions of soil erosion are often very vague. With regard to the Roman Times, geomorphic evidence shows seemingly opposing results, ranging from massive devastation to landscapes remaining stable for centuries. Unfortunately, historical documentation is lacking. In the following centuries, historical records become more frequent and more precise and observations on extreme soil erosion events are prominent. Sometimes they can be clearly linked to geomorphic evidence in the field. The advent of professional soil conservation took place in the late eighteenth century. The first extensive essay on soil conservation known to the Western world was published in Germany in 1815. The rise of professional soil conservation occurred in the late nineteenth and early twentieth centuries. Soil remediation and flood prevention programs were initiated, but the long-term success of these actions remains controversial. In recent years, increasing interest is to recover any traditional knowledge of soil

Quantification of the growth response of light quantity of greenhouse grown crops

NARCIS (Netherlands)

Marcelis, L.F.M.; Broekhuijsen, A.G.M.; Nijs, E.M.F.M.; Raaphorst, M.G.M.

2006-01-01

Growers have often assumed that a 1% increment in light results in a 1% yield increase. In this study, this rule of thumb has been evaluated for a number of greenhouse grown crops: fruit vegetables (cucumber, tomato, sweet pepper), soil grown vegetables (lettuce, radish), cut flowers (rose,

Greenhouse gas emissions and stocks of soil carbon and nitrogen from a 20-year fertilised wheat-maize intercropping system: A model approach.

Science.gov (United States)

Zhang, Xubo; Xu, Minggang; Liu, Jian; Sun, Nan; Wang, Boren; Wu, Lianhai

2016-02-01

Accurate modelling of agricultural management impacts on greenhouse gas emissions and the cycling of carbon and nitrogen is complicated due to interactions between various processes and the disturbance caused by field management. In this study, a process-based model, the Soil-Plant-Atmosphere Continuum System (SPACSYS), was used to simulate the effects of different fertilisation regimes on crop yields, the dynamics of soil organic carbon (SOC) and total nitrogen (SN) stocks from 1990 to 2010, and soil CO2 (2007-2010) and N2O (2007-2008) emissions based on a long-term fertilisation experiment with a winter-wheat (Triticum Aestivum L.) and summer-maize (Zea mays L.) intercropping system in Eutric Cambisol (FAO) soil in southern China. Three fertilisation treatments were 1) unfertilised (Control), 2) chemical nitrogen, phosphorus and potassium (NPK), and 3) NPK plus pig manure (NPKM). Statistical analyses indicated that the SPACSYS model can reasonably simulate the yields of wheat and maize, the evolution of SOC and SN stocks and soil CO2 and N2O emissions. The simulations showed that the NPKM treatment had the highest values of crop yields, SOC and SN stocks, and soil CO2 and N2O emissions were the lowest from the Control treatment. Furthermore, the simulated results showed that manure amendment along with chemical fertiliser applications led to both C (1017 ± 470 kg C ha(-1) yr(-1)) and N gains (91.7 ± 15.1 kg N ha(-1) yr(-1)) in the plant-soil system, while the Control treatment caused a slight loss in C and N. In conclusion, the SPACSYS model can accurately simulate the processes of C and N as affected by various fertilisation treatments in the red soil. Furthermore, application of chemical fertilisers plus manure could be a suitable management for ensuring crop yield and sustaining soil fertility in the red soil region, but the ratio of chemical fertilisers to manure should be optimized to reduce C and N losses to the environment. Copyright © 2015

Effects of Biofertilizer Containing Microbial of N-fixer, P Solubilizer and Plant Growth Factor Producer on Cabbage (Brassica oleraceae var. Capitata Growth And Soil Enzymatic Activities: A Greenhouse Trial

Directory of Open Access Journals (Sweden)

Sarjiya Antonius

2012-05-01

Full Text Available The objective of this greenhouse study was to evaluate the effects of four different concentrations of biofertilizers containing Pseudomonas sp., Bacillus sp. and Streptomyces sp. on soil properties and to evaluate the growth of Brassica oleraceae var. capitata. The application treatments included control (no fertilizer and four concentration of diluted biofertilizer per pot (20 ml, 40 ml, 60 mland 80 ml. The application of biofertilizer containing benefi cial bacteria signifi cantly increased the growth of B. oleraceae. The useof biofertilizer resulted higher biomass weight and length as well as root length. This greenhouse study also indicated that differentamount of biofertilizer application had almost similar effects. Microbial inoculum not only increased plant harvest, but also improvedsoil properties, such as number of microorganisms, respiration and urease activities.

Yields and Nutritional of Greenhouse Tomato in Response to Different Soil Aeration Volume at two depths of Subsurface drip irrigation

Science.gov (United States)

Li, Yuan; Niu, Wenquan; Dyck, Miles; Wang, Jingwei; Zou, Xiaoyang

2016-01-01

This study investigated the effects of 4 aeration levels (varied by injection of air to the soil through subsurface irrigation lines) at two subsurface irrigation line depths (15 and 40 cm) on plant growth, yield and nutritional quality of greenhouse tomato. In all experiments, fruit number, width and length, yield, vitamin C, lycopene and sugar/acid ratio of tomato markedly increased in response to the aeration treatments. Vitamin C, lycopene, and sugar/acid ratio increased by 41%, 2%, and 43%, respectively, in the 1.5 times standard aeration volume compared with the no-aeration treatment. An interaction between aeration level and depth of irrigation line was also observed with yield, fruit number, fruit length, vitamin C and sugar/acid ratio of greenhouse tomato increasing at each aeration level when irrigation lines were placed at 40 cm depth. However, when the irrigation lines were 15 cm deep, the trend of total fruit yields, fruit width, fruit length and sugar/acid ratio first increased and then decreased with increasing aeration level. Total soluble solids and titrable acid decreased with increasing aeration level both at 15 and 40 cm irrigation line placement. When all of the quality factors, yields and economic benefit are considered together, the combination of 40 cm line depth and “standard” aeration level was the optimum combination. PMID:27995970

[Roles of soil dissolved organic carbon in carbon cycling of terrestrial ecosystems: a review].

Science.gov (United States)

Li, Ling; Qiu, Shao-Jun; Liu, Jing-Tao; Liu, Qing; Lu, Zhao-Hua

2012-05-01

Soil dissolved organic carbon (DOC) is an active fraction of soil organic carbon pool, playing an important role in the carbon cycling of terrestrial ecosystems. In view of the importance of the carbon cycling, this paper summarized the roles of soil DOC in the soil carbon sequestration and greenhouse gases emission, and in considering of our present ecological and environmental problems such as soil acidification and climate warming, discussed the effects of soil properties, environmental factors, and human activities on the soil DOC as well as the response mechanisms of the DOC. This review could be helpful to the further understanding of the importance of soil DOC in the carbon cycling of terrestrial ecosystems and the reduction of greenhouse gases emission.

Soil Phosphorus status in Chinese greenhouse vegetable production system

DEFF Research Database (Denmark)

Kianpoor Kalkhajeh, Yusef

-1 were found in the leachates from P rich coarse-textured Tongshan soils. In contrast, DRP leaching from fine-textured Guli soils rarely exceeded the suggested environmental P threshold of 0.1 mg L-1. In accordance, a change-point Olsen P value above 41 mg kg-1 led to susbtantial DRP leaching from...

Greenhouse cooling using a rainwater basin under the greenhouse

NARCIS (Netherlands)

Campen, J.B.

2006-01-01

The objective of the study was to determine the technical and economical aspects of additional applications for a rainwater basin installed under a greenhouse. The installation for cooling the greenhouse can be placed under the greenhouse. Part of the installation consists of a short-term heat store

The greenhouse gas intensity and potential biofuel production capacity of maize stover harvest in the US Midwest

Energy Technology Data Exchange (ETDEWEB)

Jones, Curtis D. [Department of Geographical Sciences, University of Maryland, College Park MD 20742 USA; Zhang, Xuesong [Joint Global Change Research Institute, Pacific Northwest National Laboratory and University of Maryland, College Park MD 20740 USA; Reddy, Ashwan D. [Department of Geographical Sciences, University of Maryland, College Park MD 20742 USA; Robertson, G. Philip [Great Lakes Bioenergy Research Center, Michigan State University, East Lansing MI 48824 USA; W.K. Kellogg Biological Station, Michigan State University, Hickory Corners MI 49060 USA; Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing MI 48824 USA; Izaurralde, Roberto César [Department of Geographical Sciences, University of Maryland, College Park MD 20742 USA; Texas A& M AgriLife Research & Extension Center, Temple TX 76502 USA

2017-08-11

Agricultural residues are important sources of feedstock for a cellulosic biofuels industry that is being developed to reduce greenhouse gas emissions and improve energy independence. While the US Midwest has been recognized as key to providing maize stover for meeting near-term cellulosic biofuel production goals, there is uncertainty that such feedstocks can produce biofuels that meet federal cellulosic standards. Here, we conducted extensive site-level calibration of the Environmental Policy Integrated Climate (EPIC) terrestrial ecosystems model and applied the model at high spatial resolution across the US Midwest to improve estimates of the maximum production potential and greenhouse gas emissions expected from continuous maize residue-derived biofuels. A comparison of methodologies for calculating the soil carbon impacts of residue harvesting demonstrates the large impact of study duration, depth of soil considered, and inclusion of litter carbon in soil carbon change calculations on the estimated greenhouse gas intensity of maize stover-derived biofuels. Using the most representative methodology for assessing long-term residue harvesting impacts, we estimate that only 5.3 billion liters per year (bly) of ethanol, or 8.7% of the near-term US cellulosic biofuel demand, could be met under common no-till farming practices. However, appreciably more feedstock becomes available at modestly higher emissions levels, with potential for 89.0 bly of ethanol production meeting US advanced biofuel standards. Adjustments to management practices, such as adding cover crops to no-till management, will be required to produce sufficient quantities of residue meeting the greenhouse gas emission reduction standard for cellulosic biofuels. Considering the rapid increase in residue availability with modest relaxations in GHG reduction level, it is expected that management practices with modest benefits to soil carbon would allow considerable expansion of potential cellulosic

Linking soil O2, CO2, and CH4 concentrations in a wetland soil

DEFF Research Database (Denmark)

Elberling, Bo; Jensen, Louise Askær; Jørgensen, Christian Juncher

2011-01-01

and CH4 were measured in the laboratory during flooding of soil columns using a combination of planar O2 optodes and membrane inlet mass spectrometry. Microsensors were used to assess apparent diffusivity under both field and laboratory conditions. Gas concentration profiles were analyzed...... plants tissue on soil gas dynamics and greenhouse gas emissions following marked changes in water level....

Modelled impacts of mitigation measures on greenhouse gas emissions from Finnish agriculture up to 2020

Directory of Open Access Journals (Sweden)

K. REGINA

2008-12-01

Full Text Available Emission scenarios based on integrated quantitative modelling are a valuable tool in planning strategies for greenhouse gas mitigation. By estimating the potential of individual mitigation measures to reduce greenhouse gas emissions, resources can be targeted to the most promising policy measures. This paper reports two agricultural emission scenarios for Finland up to year 2020, one baseline scenario (Scenario 1 based on the projected agricultural production levels determined by markets and agricultural policy and one with selected mitigation measures included (Scenario 2. Measures selected for the analysis consisted of 1 keeping agricultural area at the current level, 2 decreasing the proportion of organic soils, 3 increasing the proportion of grass cultivation on organic soils and 4 supporting biogas production on farms. Starting from 2005, the emissions of nitrous oxide and methane from agriculture would decrease 2.3% in Scenario 1 by 2020 whereas the respective decrease would be 11.5% in Scenario 2. According to the results, mitigation measures targeted to cultivation of organic soils have the largest potential to reduce the emissions. Such measures would include reducing the area of cultivated organic soils and increasing the proportion of perennial crops on the remaining area.

Exploiting Co-Benefits of Increased Rice Production and Reduced Greenhouse Gas Emission through Optimized Crop and Soil Management.

Directory of Open Access Journals (Sweden)

Ning An

Full Text Available Meeting the future food security challenge without further sacrificing environmental integrity requires transformative changes in managing the key biophysical determinants of increasing agronomic productivity and reducing the environmental footprint. Here, we focus on Chinese rice production and quantitatively address this concern by conducting 403 on-farm trials across diverse rice farming systems. Inherent soil productivity, management practices and rice farming type resulted in confounded and interactive effects on yield, yield gaps and greenhouse gas (GHG emissions (N2O, CH4 and CO2-equivalent with both trade-offs and compensating effects. Advances in nitrogen, water and crop management (Best Management Practices-BMPs helped closing existing yield gaps and resulted in a substantial reduction in CO2-equivalent emission of rice farming despite a tradeoff of increase N2O emission. However, inherent soil properties limited rice yields to a larger extent than previously known. Cultivating inherently better soil also led to lower GHG intensity (GHG emissions per unit yield. Neither adopting BMPs only nor improving soils with low or moderate productivity alone can adequately address the challenge of substantially increasing rice production while reducing the environmental footprint. A combination of both represents the most efficient strategy to harness the combined-benefits of enhanced production and mitigating climate change. Extrapolating from our farm data, this strategy could increase rice production in China by 18%, which would meet the demand for direct human consumption of rice by 2030. It would also reduce fertilizer nitrogen consumption by 22% and decrease CO2-equivalent emissions during the rice growing period by 7% compared with current farming practice continues. Benefits vary by rice-based cropping systems. Single rice systems have the largest food provision benefits due to its wider yield gap and total cultivated area, whereas double

Transfer factors of radionuclides 137Cs and 65Zn from soil to pearl millet and sorghum

International Nuclear Information System (INIS)

Sachdev, P.; Sachdev, M.S.; Deb, D.L.

1996-01-01

The soil to plant transfer factors (TF) of 137 Cs and 65 Zn were determined for two crops, sorghum and pearl millet, under irrigated conditions in greenhouse and under rain fed conditions in field. In the greenhouse experiment, the accumulation of 137 Cs was almost doubled when the soil contamination level was doubled. Under field conditions, 137 Cs concentration in both pearl millet and sorghum grains as well as straw was nearly four times more at 148 kBq Kg -1 level of soil contamination as compared to lower level of 74 kBq kg -1 soil. The TF values for 65 Zn determined under greenhouse conditions for both the crops were nearly a hundred-fold higher as compared to 137 Cs. (author). 7 refs., 2 tabs

Avoidance of fluorinated greenhouse gases. Possibilities of an early exit; Fluorierte Treibhausgase vermeiden. Wege zum Ausstieg

Energy Technology Data Exchange (ETDEWEB)

Becken, Katja; Graaf, Daniel de; Elsner, Cornelia; Hoffmann, Gabriele; Krueger, Franziska; Martens, Kerstin; Plehn, Wolfgang; Sartorius, Rolf

2010-11-15

In comparison to carbon dioxide, fluorinated greenhouse gases are more harmful up to a factor of 24,000. Today the amount of fluorinated greenhouse gases of the world-wide emissions of climatic harmful gases amounts 2 % and increases to 6 % in the year 2050. The authors of the contribution under consideration report on possibilities for the avoidance of the emissions of fluorinated greenhouse gases. The characteristics and ecological effects of fluorinated gases as well as the development of the emission in Germany are presented. Subsequently, the applications of fluorinated hydrocarbons are described.

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

Science.gov (United States)

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

2013-04-01

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

The effects of soil flooding on the establishment of cogongrass (Imperata cylindrica), a nonindigenous invader of the southeastern United States

Science.gov (United States)

King, S.E.; Grace, J.B.

2000-01-01

Cogongrass (Imperata cylindrica), an invasive perennial introduced from Southeast Asia, is currently spreading throughout the southeastern United States from Florida to Louisiana. In the U.S., cogongrass is generally not considered a wetland species, although it's range is expanding in regions with high wetland abundance. The objective of this study was to determine if excessive soil moisture might prevent cogongrass from establishing in areas with seasonally flooded soils. In one greenhouse experiment, we examined cogongrass germination and seedling growth in soils that were freely drained, saturated, and inundated. We performed a second greenhouse experiment to evaluate growth and survival of cogongrass seedlings of four different size classes in five soil moisture treatments ranging from dry to inundated. Cogongrass germination was lowest when seeds were overtopped with water. There were no differences in germination between saturated and freely drained treatments; however, seedlings grew largest in freely drained soil and were smallest when immersed. In our second experiment, most cogongrass plants survived except when given no water, but growth differed by watering treatment depending on seedling size. Increasing moisture was more detrimental to the growth of small seedlings compared to the growth of larger cogongrass plants. Overall, cogongrass was most sensitive to soil inundation in the earliest stages of establishment; thus, excessive moisture conditions in the spring, during early seedling development, could restrict invasion of cogongrass by seed. Once cogongrass is established, however, its tolerance of flooding appears to increase.

REVISITING THE SCATTERING GREENHOUSE EFFECT OF CO2 ICE CLOUDS

International Nuclear Information System (INIS)

Kitzmann, D.

2016-01-01

Carbon dioxide ice clouds are thought to play an important role for cold terrestrial planets with thick CO 2 dominated atmospheres. Various previous studies showed that a scattering greenhouse effect by carbon dioxide ice clouds could result in a massive warming of the planetary surface. However, all of these studies only employed simplified two-stream radiative transfer schemes to describe the anisotropic scattering. Using accurate radiative transfer models with a general discrete ordinate method, this study revisits this important effect and shows that the positive climatic impact of carbon dioxide clouds was strongly overestimated in the past. The revised scattering greenhouse effect can have important implications for the early Mars, but also for planets like the early Earth or the position of the outer boundary of the habitable zone

Gardening with Greenhouses

Science.gov (United States)

Keeler, Rusty

2010-01-01

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

Accounting for Carbon Stocks in Soils and Measuring GHGs Emission Fluxes from Soils: Do We Have the Necessary Standards?

Directory of Open Access Journals (Sweden)

Antonio Bispo

2017-07-01

Full Text Available Soil is a key compartment for climate regulation as a source of greenhouse gases (GHGs emissions and as a sink of carbon. Thus, soil carbon sequestration strategies should be considered alongside reduction strategies for other greenhouse gas emissions. Taking this into account, several international and European policies on climate change are now acknowledging the importance of soils, which means that proper, comparable and reliable information is needed to report on carbon stocks and GHGs emissions from soil. It also implies a need for consensus on the adoption and verification of mitigation options that soil can provide. Where consensus is a key aspect, formal standards and guidelines come into play. This paper describes the existing ISO soil quality standards that can be used in this context, and calls for new ones to be developed through (international collaboration. Available standards cover the relevant basic soil parameters including carbon and nitrogen content but do not yet consider the dynamics of those elements. Such methods have to be developed together with guidelines consistent with the scale to be investigated and the specific use of the collected data. We argue that this standardization strategy will improve the reliability of the reporting procedures and results of the different climate models that rely on soil quality data.

Greener greenhouses

Energy Technology Data Exchange (ETDEWEB)

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

2010-09-15

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

Greenhouse gas emissions from food and garden waste composting

OpenAIRE

Ermolaev, Evgheni

2015-01-01

Composting is a robust waste treatment technology. Use of finished compost enables plant nutrient recycling, carbon sequestration, soil structure improvement and mineral fertiliser replacement. However, composting also emits greenhouse gases (GHG) such as methane (CH₄) and nitrous oxide (N₂O) with high global warming potential (GWP). This thesis analysed emissions of CH₄ and N₂O during composting as influenced by management and process conditions and examined how these emissions could be ...

Interspecific competition of early successional plant species in ex-arable fields as influenced by plant-soil feedback

OpenAIRE

Jing, Jingying; Bezemer, T. Martijn; Van der Putten, Wim H.

2015-01-01

Plant–soil feedback can affect plants that belong to the same (intraspecific feedback) or different species (interspecific feedback). However, little is known about how intra- and interspecific plant–soil feedbacks influence interspecific plant competition. Here, we used plants and soil from early-stage ex-arable fields to examine how intra- and interspecific plant–soil feedbacks affect the performance of 10 conditioning species and the focal species, Jacobaea vulgaris. Plants were grown alon...

Adaptation of a leaf wetness duration model for tomato under Colombian greenhouse conditions

Directory of Open Access Journals (Sweden)

Rodrigo Gil

2015-04-01

Full Text Available Greenhouse tomato production uses structures that protect crops from extreme environmental conditions; however, the climate inside Colombian greenhouses is often not optimal and crops are susceptible to attack by fungal diseases. The use of simulation models for early warnings of attack by diseases have helped to rationalize the use of chemical pesticides by increasing their efficiency when sprayed at critical times of disease onset. The aim of this study was to calibrate the surface wetness energy balance (SWEB model to estimate the leaf wetness duration (LWD for greenhouse tomatoes in the Alto Ricaurte province (Boyaca. For the validation, the performances of the SWEB model were evaluated by comparing a simulated LWD with records from dielectric leaf wetness sensors. The model adequately represented the phenomenon of free water on the leaves for plants in two greenhouses of Santa Sofia and Sutamarchan. The model simulated an average LWD of 9.9 and 12.1 hours day-1 in Santa Sofia and Sutamarchan, respectively. However, the simulations for the two greenhouses indicated different behaviors, with average differences between the observed and simulated daily number of hours with free water of 0.8 hours for Santa Sofia, while, for Sutamarchan, the difference reached 4 hours. The fraction of correct estimates index indicated the model had the ability to correctly predict 92 and 72% of the hours with a presence or absence of LWD in Santa Sofia and Sutamarchan, respectively. The SWEB model is a useful tool for early warnings for the attack of fungal diseases in greenhouse tomatoes. However, due to the shortcomings of the greenhouse structures used for production, the crops are highly susceptible to attack from these pathogens.

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

Science.gov (United States)

Ti, Chaopu; Luo, Yongxia; Yan, Xiaoyuan

2015-12-01

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

Early Response of Soil Properties and Function to Riparian Rainforest Restoration

Science.gov (United States)

Gageler, Rose; Bonner, Mark; Kirchhof, Gunnar; Amos, Mark; Robinson, Nicole; Schmidt, Susanne; Shoo, Luke P.

2014-01-01

Reforestation of riparian zones is increasingly practiced in many regions for purposes of biodiversity conservation, bank stabilisation, and improvement in water quality. This is in spite of the actual benefits of reforestation for recovering underlying soil properties and function remaining poorly understood. Here we compare remnant riparian rainforest, pasture and reforestation plantings aged 2–20 years in an Australian subtropical catchment on ferrosols to determine the extent to which reforestation restores key soil properties. Of the nine soil attributes measured (total nitrogen, nitrate and ammonium concentrations, net nitrification and ammonification rates, organic carbon, bulk density, fine root biomass and water infiltration rates), only infiltration rates were significantly lower in pasture than remnant riparian rainforest. Within reforestation plantings, bulk density decreased up to 1.4-fold and infiltration rates increased up to 60-fold with time post-reforestation. Our results suggest that the main outcome of belowground processes of early reforestation is the recovery of the soils' physical structure, with potential beneficial ecosystem services including reduced runoff, erosion and associated sediment and nutrient loads in waterways. We also demonstrate differential impacts of two commonly planted tree species on a subset of soil properties suggesting that preferential planting of select species could accelerate progress on specific restoration objectives. PMID:25117589

Early response of soil properties and function to riparian rainforest restoration.

Directory of Open Access Journals (Sweden)

Rose Gageler

Full Text Available Reforestation of riparian zones is increasingly practiced in many regions for purposes of biodiversity conservation, bank stabilisation, and improvement in water quality. This is in spite of the actual benefits of reforestation for recovering underlying soil properties and function remaining poorly understood. Here we compare remnant riparian rainforest, pasture and reforestation plantings aged 2-20 years in an Australian subtropical catchment on ferrosols to determine the extent to which reforestation restores key soil properties. Of the nine soil attributes measured (total nitrogen, nitrate and ammonium concentrations, net nitrification and ammonification rates, organic carbon, bulk density, fine root biomass and water infiltration rates, only infiltration rates were significantly lower in pasture than remnant riparian rainforest. Within reforestation plantings, bulk density decreased up to 1.4-fold and infiltration rates increased up to 60-fold with time post-reforestation. Our results suggest that the main outcome of belowground processes of early reforestation is the recovery of the soils' physical structure, with potential beneficial ecosystem services including reduced runoff, erosion and associated sediment and nutrient loads in waterways. We also demonstrate differential impacts of two commonly planted tree species on a subset of soil properties suggesting that preferential planting of select species could accelerate progress on specific restoration objectives.

Soil CO2 production in upland tundra where permafrost is thawing

Science.gov (United States)

Hanna Lee; Edward A.G. Schuur; Jason G. Vogel

2010-01-01

Permafrost soils store nearly half of global soil carbon (C), and therefore permafrost thawing could lead to large amounts of greenhouse gas emissions via decomposition of soil organic matter. When ice-rich permafrost thaws, it creates a localized surface subsidence called thermokarst terrain, which changes the soil microenvironment. We used soil profile CO2...

Evaluation of Phosphorus Leaching in an Agricultural Soil under Different Soil Amendments

OpenAIRE

ERDONA DEMIRAJ; FERDI BRAHUSHI; JAMARBËR MALLTEZI; SULEJMAN SULÇE

2017-01-01

The transport of Phosphorus (P) from agricultural soils to surface waters sensitive to eutrophication has long been a world-wide environmental concern. The intensive agricultural activity in the upper Shkodra fields, combined with others point source pollution, probably, intensify eutrophication of the Shkodra Lake. These Clay Loamy soils (calcaric Regosols) are characterized by low organic matter, N and P, with a high water percolation. An experiment was conducted at Greenhouse Research Stat...

Impact of long-term conservation management on soil microbial N cycling and greenhouse gas emissions in a humid agroecosystem in West Tennessee

Science.gov (United States)

Schaeffer, S. M.; Konkel, J. M.; Jin, V.

2017-12-01

Conservation practices such as no-tillage, cover crops, and reduced mineral fertilizer application are thought to help mitigate atmospheric greenhouse gas (GHG) concentrations through building soil organic matter. However, some studies have shown that both no-till and cover crops can increase GHG emissions, perhaps due to increased microbial activity. It is possible that these results are confounded by perturbations caused when management practices are newly implemented. There is a clear lack of data from long-term sites where experimental plots are well equilibrated to the management systems. Starting in 2016, we measured fluxes of nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2) in twelve combinations of tillage (disk, no-till), N fertilizer rate (0, 67 kg N ha-1), and winter cover crops (none, hairy vetch, winter wheat) under continuous cotton production for 35 years. During the cotton growing season, the largest daily fluxes of N2O (36.9±11.9 g N ha-1 d-1) occurred in tilled plots regardless of cover crop or fertilization rate. However, over the entire year, the largest fluxes were observed during winter cover crop growth (63.0±21.4 g N ha-1 d-1). Overall, N2O fluxes were lower in no-till compared to tilled soils, save those under hairy vetch, a nitrogen fixing cover crop. These results, combined with our observation of higher rates of microbial N mineralization and nitrification in no-till and vetch plots, suggest vetch cover crops may stimulate both GHG and inorganic N production. We observed seasonal patterns in CH4 flux with net CH4 production during Spring and early Summer (from 0.2±0.8 to 4.8±3.2 g C ha-1 d-1), switching to net CH4 consumption by late summer (from -6.3±3.4 to 0.8±0.5 g C ha-1 d-1). Cumulative CH4 fluxes suggest that reduced tillage and fertilization may change these agroecosystems from weak sources to weak sinks for CH4. Our results highlight the impact of nitrogen availability on GHG emissions, and the need for improved

Estimating greenhouse gas emissions at the soil-atmosphere interface in forested watersheds of the US Northeast.

Science.gov (United States)

Gomez, Joshua; Vidon, Philippe; Gross, Jordan; Beier, Colin; Caputo, Jesse; Mitchell, Myron

2016-05-01

Although anthropogenic emissions of greenhouse gases (GHG: CO2, CH4, N2O) are unequivocally tied to climate change, natural systems such as forests have the potential to affect GHG concentration in the atmosphere. Our study reports GHG emissions as CO2, CH4, N2O, and CO2eq fluxes across a range of landscape hydrogeomorphic classes (wetlands, riparian areas, lower hillslopes, upper hillslopes) in a forested watershed of the Northeastern USA and assesses the usability of the topographic wetness index (TWI) as a tool to identify distinct landscape geomorphic classes to aid in the development of GHG budgets at the soil atmosphere interface at the watershed scale. Wetlands were hot spots of GHG production (in CO2eq) in the landscape owing to large CH4 emission. However, on an areal basis, the lower hillslope class had the greatest influence on the net watershed CO2eq efflux, mainly because it encompassed the largest proportion of the study watershed (54 %) and had high CO2 fluxes relative to other land classes. On an annual basis, summer, fall, winter, and spring accounted for 40, 27, 9, and 24 % of total CO2eq emissions, respectively. When compared to other approaches (e.g., random or systematic sampling design), the TWI landscape classification method was successful in identifying dominant landscape hydrogeomorphic classes and offered the possibility of systematically accounting for small areas of the watershed (e.g., wetlands) that have a disproportionate effect on total GHG emissions. Overall, results indicate that soil CO2eq efflux in the Archer Creek Watershed may exceed C uptake by live trees under current conditions.

Agricultural opportunities to mitigate greenhouse gas emissions

International Nuclear Information System (INIS)

Johnson, Jane M.-F.; Franzluebbers, Alan J.; Weyers, Sharon Lachnicht; Reicosky, Donald C.

2007-01-01

Agriculture is a source for three primary greenhouse gases (GHGs): CO 2 , CH 4 , and N 2 O. It can also be a sink for CO 2 through C sequestration into biomass products and soil organic matter. We summarized the literature on GHG emissions and C sequestration, providing a perspective on how agriculture can reduce its GHG burden and how it can help to mitigate GHG emissions through conservation measures. Impacts of agricultural practices and systems on GHG emission are reviewed and potential trade-offs among potential mitigation options are discussed. Conservation practices that help prevent soil erosion, may also sequester soil C and enhance CH 4 consumption. Managing N to match crop needs can reduce N 2 O emission and avoid adverse impacts on water quality. Manipulating animal diet and manure management can reduce CH 4 and N 2 O emission from animal agriculture. All segments of agriculture have management options that can reduce agriculture's environmental footprint. - Management options can be used to reduce agriculture's environmental impacts

Greenhouse impact of Finnish peatlands 1900-2100

Energy Technology Data Exchange (ETDEWEB)

Laine, J; Minkkinen, K [Helsinki Univ. (Finland). Dept. of Ecology; Tolonen, K; Turunen, J [Joensuu Univ. (Finland). Dept. of Biology; Martikainen, P; Nykaenen, H [National Public Health Inst. Kuopio (Finland). Dept. of Environmental Microbiology; Sinisalo, J; Savolainen, I [VTT Energy, Espoo (Finland)

1997-12-31

Northern peatlands are significant in regulating the global climate. While sequestering carbon dioxide (CO{sub 2}, ca. 100 Tg C a{sup -} {sup 1}), these peatlands release cat 24-39 Tg methane (CH{sub 4}) annually to the atmosphere. This is 5-15 % of the annual anthropogenic and 10-35 % of the annual natural CH4 emissions to the atmosphere. The greenhouse gas balance of peatlands may change as a consequence of water level drawdown after land use change, or if summers become warmer and drier, as has been predicted for high latitudes after climatic warming. Currently, some 15 million hectares of northern peatlands and other wetlands have been drained for forestry. More than 90 % of this area is found in Scandinavia and the former Soviet Union. The area drained annually has, however, been declining during the last two decades and, in Finland for instance the annual drained area of nearly 300 000 hectares in the late 1960`s has decreased to cat 35 000 hectares in the early 1990`s. Radiative forcing is the change in the radiative energy balance at the tropopause and it is the driving force behind the greenhouse effect. It is a common quantity for most greenhouse gases and takes into account the dynamics of the greenhouse impact. Radiative forcing model was used to compute the greenhouse impact of the drainage of the peatlands, combining the effects of CO{sub 2} and CH4 balances; N{sub 2}O was not included in the calculations because its contribution is minor. (14 refs.)

Greenhouse impact of Finnish peatlands 1900-2100

Energy Technology Data Exchange (ETDEWEB)

Laine, J.; Minkkinen, K. [Helsinki Univ. (Finland). Dept. of Ecology; Tolonen, K.; Turunen, J. [Joensuu Univ. (Finland). Dept. of Biology; Martikainen, P.; Nykaenen, H. [National Public Health Inst. Kuopio (Finland). Dept. of Environmental Microbiology; Sinisalo, J.; Savolainen, I. [VTT Energy, Espoo (Finland)

1996-12-31

Northern peatlands are significant in regulating the global climate. While sequestering carbon dioxide (CO{sub 2}, ca. 100 Tg C a{sup -} {sup 1}), these peatlands release cat 24-39 Tg methane (CH{sub 4}) annually to the atmosphere. This is 5-15 % of the annual anthropogenic and 10-35 % of the annual natural CH4 emissions to the atmosphere. The greenhouse gas balance of peatlands may change as a consequence of water level drawdown after land use change, or if summers become warmer and drier, as has been predicted for high latitudes after climatic warming. Currently, some 15 million hectares of northern peatlands and other wetlands have been drained for forestry. More than 90 % of this area is found in Scandinavia and the former Soviet Union. The area drained annually has, however, been declining during the last two decades and, in Finland for instance the annual drained area of nearly 300 000 hectares in the late 1960`s has decreased to cat 35 000 hectares in the early 1990`s. Radiative forcing is the change in the radiative energy balance at the tropopause and it is the driving force behind the greenhouse effect. It is a common quantity for most greenhouse gases and takes into account the dynamics of the greenhouse impact. Radiative forcing model was used to compute the greenhouse impact of the drainage of the peatlands, combining the effects of CO{sub 2} and CH4 balances; N{sub 2}O was not included in the calculations because its contribution is minor. (14 refs.)

Food for early succession birds: relationships among arthropods, shrub vegetation, and soil

Science.gov (United States)

Richard N. Conner; Daniel Saenz; D. Brent Burt

2006-01-01

During spring and early summer, shrub- and herbaceous-level vegetation provides nesting and foraging habitat for many shrub-habitat birds. We examined relationships among arthropod biomass and abundance, foliage leaf surface area and weight, vegetation ground cover, soil characteristics, relative humidity, and temperature to evaluate what factors may influence...

Effect of soil solarization on soil-borne pathogens

International Nuclear Information System (INIS)

Sobh, Hana

1995-01-01

Author.Soil solarization was conducted at three locations on the Lebanese coast. Maximum soil temperatures recorded were 53 and 48 celsius degrees at Jiyeh, 48.9, 46 and 43 celsius degrees at Naameh and 48, 45 and 43.5 celsius degrees at Khaldeh at 5, 15 and 25cm soil depths respectively. Mean soil temperatures recorded at 3pm were at Jiyeh 51.6, 47 and 46 celsius degrees compared to Naameh 47, 45 and 41 celsius degrees and Khaldeh 44, 42 and 41 celsius degrees at 5, 15 and 25 cm respectively. The mean temperature in solarized soils were 7.3 to 15 celsius degrees higher than those of the nonsolarized soils indicating a sustained increase of soil temperature in the solarized soils. The effect of soil solarization on artificially introduced fungal pathogens in the soil at Khaldeh, resulted in complete destruction of sclerotia of Sclerotinia spp. at three depths studied. However, with respect to the two other pathogens tested, solarization resulted in reduction of the viability of microsclerotia of Verticillium spp. by 99-79% and of Fusarium oxysporum f. sp. melonis inoculum by 88-54% at 5 and 15 cm respectively, but only by 45% and 14% reduction at 25 cm. This level of control is significant when it is compared to the percentage of control where the level of reduction of inoculum viability did not exceed 10% at any soil depth. As there were contradicting reports in the literature on nematodes, two field trials in greenhouses were conducted to study the possibility of integrating 2 methods for management on nematodes. Soil solarization alone or in combination with biological control of nematodes using Arthrobotrys spp. and Dactyl ella brocophaga to control the root-knot nematodes on two crops, tomato at Naameh and cucumber at Jiyeh were compared to Methyl Bromide treatment. It was evident that, even on a very susceptible crop like cucumber, the integration of biological control and soil solarization gave a good level of control similar to methyl bromide. Neither root

Fungicide Effect on Glomus Intrarradices in Different Genotypes of Beans (Phaseolus Vulgaris L., OAT (Avena Sativa L., and Wheat (Triticum Aaestivum L. Growth Cultivated in Two Soil Types under Greenhouse Conditions

Directory of Open Access Journals (Sweden)

Abdul Khalil Gardezi

2013-12-01

Full Text Available The objective of this research was to evaluate the effect of fungicides on the association with Glomus intraradices and soil contamination on three genotypes of beans (Phaseolus vulgaris L., one of oat (Avena sativa L., and another one of wheat (Triticum aestivum L.. The study was done under greenhouse conditions at the Montecillo Campus of the Postgraduate College, Mexico. Two soils were used, one irrigated with sewage water and the other one with clean water from a well. Half of the plants were inoculated with Glomus intraradices. Metacaptan was used as a fungicide applied to half of the seeds. The pH of the soil was alkaline. Electric conductivity, and organic matter, nitric and ammoniac nitrogen, phosphorous, copper and nickel quantities were higher on the soils irrigated with sewage water. The soil contamination did not affect significantly plant responses in this study. It is concluded that endomycorrhiza inoculation (Glomus intraradices gave better growth and yield, especially in beans. The application of fungicides improved plant growth.

Early action to reduce greenhouse gas emissions before the commitment period of the Kyoto protocol: advantages and disadvantages.

Science.gov (United States)

Michaelowa, A; Rolfe, C

2001-09-01

Current "business as usual" projections suggest greenhouse gas emissions from industrialized nations will grow substantially over the next decade. However, if it comes into force, the Kyoto Protocol will require industrialized nations to reduce emissions to an average of 5% below 1990 levels in the 2008-2012 period. Taking early action to close this gap has a number of advantages. It reduces the risks of passing thresholds that trigger climate change "surprises." Early action also increases future generations' ability to choose greater levels of climate protection, and it leads to faster reductions of other pollutants. From an economic sense, early action is important because it allows shifts to less carbon-intensive technologies during the course of normal capital stock turnover. Moreover, many options for emission reduction have negative costs, and thus are economically worthwhile, because of paybacks in energy costs, healthcare costs, and other benefits. Finally, early emission reductions enhance the probability of successful ratification and lower the risk of noncompliance with the protocol. We discuss policy approaches for the period prior to 2008. Disadvantages of the current proposals for Credit for Early Action are the possibility of adverse selection due to problematic baseline calculation methods as well as the distributionary impacts of allocating a part of the emissions budget already before 2008. One simple policy without drawbacks is the so-called baseline protection, which removes the disincentive to early action due to the expectation that businesses may, in the future, receive emission rights in proportion to past emissions. It is particularly important to adopt policies that shift investment in long-lived capital stock towards less carbon-intensive technologies and to encourage innovation and technology development that will reduce future compliance costs.

Organic amendments and nutrient leaching in soil columns

Science.gov (United States)

The lack of nutrient build up in reclaimed coal mine soils would therefore require additional inputs to maintain plant productivity and establishment of a healthy ecosystem. In a greenhouse experiment, reclaimed coal mine soil were amended with fresh and composted poultry manure at the rates based ...

Nitrous oxide emissions from an intensively managed greenhouse vegetable cropping system in Northern China

International Nuclear Information System (INIS)

He Feifei; Jiang Rongfeng; Chen Qing; Zhang Fusuo; Su Fang

2009-01-01

Nitrous oxide (N 2 O) emissions from a typical greenhouse vegetable system in Northern China were measured from February 2004 to January 2006 using a close chamber method. Four nitrogen management levels (NN, MN, CN, and SN) were used. N 2 O emissions occurred intermittently in the growing season, strongly correlating with N fertilization and irrigation. No peak emissions were observed after fertilization in the late Autumn season due to low soil temperature. 57-94% of the seasonal N 2 O emissions came from the initial growth stage, corresponding to the rewetting process in the soil. The annual N 2 O emissions ranged from 2.6 to 8.8 kg N ha -1 yr -1 , accounting for 0.27-0.30% of the annual nitrogen input. Compared with conventional N management, site-specific N management reduced N fertilization rate by 69% in 2004 and by 76% in 2005, and consequently reduced N 2 O emissions by 51% in 2004 and 27% in 2005, respectively. - High N 2 O emissions coming from the initial growth stage can be attributed to the rewetting process in the greenhouse soil.

Deep percolation in greenhouse-cultivated celery using the technique of subsurface film strips placement

Directory of Open Access Journals (Sweden)

Zhida Du

2014-05-01

Full Text Available To reduce the deep percolation during greenhouse vegetable cultivation, the technique of subsurface film strips placement was tested. Four treatments with two kinds of cross-sections (flat and U-shaped and two different spacings (10 cm and 40 cm of subsurface film strips were arranged in a greenhouse before planting celery. At the same time, a non-film treatment was arranged for comparison. Soil water content was measured and irrigation time was adjusted according to the soil water content. Evapotranspiration of celery during growth was calculated by the method of energy balance and the deep percolation was calculated by the equation of water balance. Deep percolation was reduced in all experimental treatments. Greater reduction in deep percolation was observed when using U-shaped cross-section strips compared with that using the flat cross-section strips. In addition, greater reduction in deep percolation was observed when the spacing between the film strips was smaller. The results of this test showed that the technique of subsurface film strips placement can reduce deep percolation and conserve irrigation water for greenhouse vegetables cultivation. However, the optimal layout variables for the use of the technique of subsurface film strips placement need further experimental and numerical analysis.

Effect of cover crops on greenhouse gas emissions in an irrigated field under integrated soil fertility management

Science.gov (United States)

Guardia, Guillermo; Abalos, Diego; García-Marco, Sonia; Quemada, Miguel; Alonso-Ayuso, María; Cárdenas, Laura M.; Dixon, Elizabeth R.; Vallejo, Antonio

2016-09-01

Agronomical and environmental benefits are associated with replacing winter fallow by cover crops (CCs). Yet, the effect of this practice on nitrous oxide (N2O) emissions remains poorly understood. In this context, a field experiment was carried out under Mediterranean conditions to evaluate the effect of replacing the traditional winter fallow (F) by vetch (Vicia sativa L.; V) or barley (Hordeum vulgare L.; B) on greenhouse gas (GHG) emissions during the intercrop and the maize (Zea mays L.) cropping period. The maize was fertilized following integrated soil fertility management (ISFM) criteria. Maize nitrogen (N) uptake, soil mineral N concentrations, soil temperature and moisture, dissolved organic carbon (DOC) and GHG fluxes were measured during the experiment. Our management (adjusted N synthetic rates due to ISFM) and pedo-climatic conditions resulted in low cumulative N2O emissions (0.57 to 0.75 kg N2O-N ha-1 yr-1), yield-scaled N2O emissions (3-6 g N2O-N kg aboveground N uptake-1) and N surplus (31 to 56 kg N ha-1) for all treatments. Although CCs increased N2O emissions during the intercrop period compared to F (1.6 and 2.6 times in B and V, respectively), the ISFM resulted in similar cumulative emissions for the CCs and F at the end of the maize cropping period. The higher C : N ratio of the B residue led to a greater proportion of N2O losses from the synthetic fertilizer in these plots when compared to V. No significant differences were observed in CH4 and CO2 fluxes at the end of the experiment. This study shows that the use of both legume and nonlegume CCs combined with ISFM could provide, in addition to the advantages reported in previous studies, an opportunity to maximize agronomic efficiency (lowering synthetic N requirements for the subsequent cash crop) without increasing cumulative or yield-scaled N2O losses.

The Influence of Soil Displacement in Bavarian Agricultural Landscapes on the Land-Atmosphere Exchange of Greenhouse Gases.

Science.gov (United States)

Smidt, J.; Schmid, H. P. E.

2016-12-01

The terrestrial biosphere represents the world's second-largest stock of carbon, after the oceans, estimated to be 2300 Gt carbon with 1500 Gt of organic carbon (Kirkels et al., 2014). In agricultural landscapes, erosion and deposition caused by tillage and subsequent heavy precipitation redistribute large amounts of soil and therefore carbon (Van Oost et al., 2007). Erosion rates in areas of agricultural production are 1-2 magnitudes larger than in areas covered with native vegetation (Montgomery, 2007). Landscapes in the German state of Bavaria have been used for agricultural production for thousands of years. Within the framework of the project "Bavarian Landscapes Under Climate Change," a multi-method approach is taken. At two distinct watersheds in Bavaria, we attempt to quantify the effect of soil displacement on the fluxes of CO2, N2O and CH4 using continuous eddy covariance (EC) data, small manual gas chamber measurements and a soil laboratory incubation experiment designed to simulate an erosion event. The pre-alpine site of Rottenbuch, part of the TERENO network, is located at 690 masl and characterized by molasses and carbonic/dolomitic fluvioglacial sediments. The Otterbach site, part of the Bavarian Forest, lies at 350 masl and is dominated by granite and gneiss rock. The sites have an annual precipitation of 1200 and 700 mm, respectively. In Rottenbuch, the downslope area is managed grassland and the upslope area is grazed part of the year. In Otterbach, the downslope field is organic grassland, and the upslope area is used for agricultural production. There is a standard EC station at each site, as well as automatic chambers (Rottenbuch) and manual chambers (Otterbach). The data collected will be used to calibrate, run and verify numerical models to ascertain the sensitivity of the fluxes to biological, biochemical and physical processes and ultimately bring light to the question of agricultural landscapes as sinks or sources of greenhouse gases.

REVISITING THE SCATTERING GREENHOUSE EFFECT OF CO{sub 2} ICE CLOUDS

Energy Technology Data Exchange (ETDEWEB)

Kitzmann, D., E-mail: daniel.kitzmann@csh.unibe.ch [Center for Space and Habitability, University of Bern, Sidlerstr. 5, 3012 Bern (Switzerland)

2016-02-01

Carbon dioxide ice clouds are thought to play an important role for cold terrestrial planets with thick CO{sub 2} dominated atmospheres. Various previous studies showed that a scattering greenhouse effect by carbon dioxide ice clouds could result in a massive warming of the planetary surface. However, all of these studies only employed simplified two-stream radiative transfer schemes to describe the anisotropic scattering. Using accurate radiative transfer models with a general discrete ordinate method, this study revisits this important effect and shows that the positive climatic impact of carbon dioxide clouds was strongly overestimated in the past. The revised scattering greenhouse effect can have important implications for the early Mars, but also for planets like the early Earth or the position of the outer boundary of the habitable zone.

Proximal sensing for soil carbon accounting

OpenAIRE

England, Jacqueline R.; Viscarra Rossel, Raphael A.

2018-01-01

Maintaining or increasing soil organic carbon (C) is vital for securing food production and for mitigating greenhouse gas (GHG) emissions, climate change, and land degradation. Some land management practices in cropping, grazing, horticultural, and mixed farming systems can be used to increase organic C in soil, but to assess their effectiveness, we need accurate and cost-efficient methods for measuring and monitoring the change. To determine the stock of organic C in soil, one requires...

A global spectral library to characterize the world's soil

NARCIS (Netherlands)

Viscarra Rossel, R.A.; Behrens, T.; Ben-Dor, E.; Bartholomeus, H.M.

2016-01-01

Soil provides ecosystem services, supports human health and habitation, stores carbon and regulates emissions of greenhouse gases. Unprecedented pressures on soil from degradation and urbanization are threatening agro-ecological balances and food security. It is important that we learn more about

Is credit for early action credible early action?

International Nuclear Information System (INIS)

Rolfe, C.; Michaelowa, A.; Dutschke, M.

1999-12-01

Credit for early action as a tool for greenhouse gas emissions reduction is compared with various market instruments as a means of narrowing the gap between projected emissions and those of the Kyoto Protocol. Market instruments work by creating a market price for emissions and use the market to encourage reductions at the lowest price, which is done by placing limits on greenhouse gas emissions and allowing the market to decide where reductions occur, or by imposing a carbon tax or emissions charge. While they can be applied within a sector, they are usually used to encourage reductions throughout the economy or across large sectors. Credit for early action also creates an incentive for emissions reductions throughout the economy or at least across many sectors. Credit for early action tools do not work by either imposing a carbon tax or emissions charge or placing limits on emissions, rather they promise that entities that take action against greenhouse gases prior to the imposition of a carbon tax or emissions limits will receive a credit against future taxes or limits. An overview is provided of the Kyoto Protocol and the rationale for taking early action, and a review is included of the theory and specific proposals for market instruments and credit for early action. A comparative analysis is provided of these approaches by examining their relative efficiency, environmental effectiveness, and impacts on the redistribution of wealth. Credit for early action is viewed as problematic on a number of counts and is seen as an interim strategy for imposition while political support for market instruments develop. The environmental effectiveness of credit for early action is very difficult to predict, and credit for early action programs do not yield the lowest cost emissions reductions. Credit for early action programs will not achieve compliance with the Kyoto Protocol at the lowest cost, and credits for early action will increase the compliance costs for those who

Phosphorus saturation and mobilization in two typical Chinese greenhouse vegetable soils

DEFF Research Database (Denmark)

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

2017-01-01

, with a mean of 3.43 mg L(-1), were found in the leachates from P rich Tongshan soils. In contrast, P leaching from fine-textured but less P rich Guli soils rarely exceeded the suggested environmental P threshold of 0.1 mg L(-1). Strong linear correlations were found between different soil test P measures...

Changes in the soil environment from excessive application of fertilizers and manures to two contrasting intensive cropping systems on the North China Plain

International Nuclear Information System (INIS)

Ju, X.T.; Kou, C.L.; Christie, P.; Dou, Z.X.; Zhang, F.S.

2007-01-01

Effects of excessive fertilizer and manure applications on the soil environment were compared in greenhouse vegetable systems shifted from wheat-maize rotations 5-15 years previously and in wheat-maize rotations. N, P and K surpluses to the greenhouses were 4328, 1337 and 1466 kg ha -1 year -1 , respectively compared to 346, 65 and -163 kg ha -1 year -1 to wheat-maize fields. Subsequently, substantial mineral N and available P and K accumulated in the soil and leaching occurred down the soil profile in the greenhouses. Soil pH under vegetables was significantly lower than in the wheat-maize fields, while the EC was significantly higher in the vegetable soils. The mean Cd concentration in the vegetable soils was 2.8 times that in the wheat-maize rotations. Due to excessive fertilizer application in greenhouse vegetable production in northeast China, excessive salt and nitrate concentrations may accumulate and soil quality may deteriorate faster than in conventional wheat-maize rotations. - Extremely high nutrient inputs to intensively managed vegetable crops in northeast China may lead to very serious degradation of soil and water quality

Changes in the soil environment from excessive application of fertilizers and manures to two contrasting intensive cropping systems on the North China Plain

Energy Technology Data Exchange (ETDEWEB)

Ju, X.T. [Key Laboratory of Plant-Soil Interactions, Ministry of Education, College of Agricultural Resources and Environmental Sciences, China Agricultural University, Beijing 100094 (China)]. E-mail: juxt@cau.edu.cn; Kou, C.L. [Key Laboratory of Plant-Soil Interactions, Ministry of Education, College of Agricultural Resources and Environmental Sciences, China Agricultural University, Beijing 100094 (China); Institute of Soil and Fertilization, Henan Academy of Agricultural Sciences, Zhengzhou, 450002 (China); Christie, P. [Key Laboratory of Plant-Soil Interactions, Ministry of Education, College of Agricultural Resources and Environmental Sciences, China Agricultural University, Beijing 100094 (China); Agricultural and Environmental Science Department, Queen' s University Belfast, Newforge Lane, Belfast BT9 5PX (United Kingdom); Dou, Z.X. [Center for Animal Health and Productivity, Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, 382 West Street Road, Kennett Square, PA 19348 (United States); Zhang, F.S. [Key Laboratory of Plant-Soil Interactions, Ministry of Education, College of Agricultural Resources and Environmental Sciences, China Agricultural University, Beijing 100094 (China)

2007-01-15

Effects of excessive fertilizer and manure applications on the soil environment were compared in greenhouse vegetable systems shifted from wheat-maize rotations 5-15 years previously and in wheat-maize rotations. N, P and K surpluses to the greenhouses were 4328, 1337 and 1466 kg ha{sup -1} year{sup -1}, respectively compared to 346, 65 and -163 kg ha{sup -1} year{sup -1} to wheat-maize fields. Subsequently, substantial mineral N and available P and K accumulated in the soil and leaching occurred down the soil profile in the greenhouses. Soil pH under vegetables was significantly lower than in the wheat-maize fields, while the EC was significantly higher in the vegetable soils. The mean Cd concentration in the vegetable soils was 2.8 times that in the wheat-maize rotations. Due to excessive fertilizer application in greenhouse vegetable production in northeast China, excessive salt and nitrate concentrations may accumulate and soil quality may deteriorate faster than in conventional wheat-maize rotations. - Extremely high nutrient inputs to intensively managed vegetable crops in northeast China may lead to very serious degradation of soil and water quality.

Effect of plant resistance and BioAct WG (Purpureocillium lilacinum strain 251) on Meloidogyne incognita in a tomato-cucumber rotation in a greenhouse.

Science.gov (United States)

Giné, Ariadna; Sorribas, Francisco J

2017-05-01

The effectiveness of combining resistant tomato with BioAct WG (Purpureocillium lilacinum strain 251, Pl251) against Meloidogyne incognita was assessed in a tomato-cucumber rotation in a greenhouse over 2 years. Additionally, the enzymatic activity of the fungus, the percentage of fungal egg and juvenile parasitism, cardinal temperatures and the effect of water potential on mycelial growth and the soil receptivity to Pl251 were determined in vitro. Plant resistance was the only factor that suppressed nematode and crop yield losses. Percentage of egg parasitism in plots treated with BioAct WG was less than 2.6%. However, under in vitro conditions, Pl251 showed protease, lipase and chitinase activities and parasitised 94.5% of eggs, but no juveniles. Cardinal temperatures were 14.2, 24-26 and 35.4 °C. The maximum Pl251 mycelial growth was at -0.25 MPa and 25 °C. Soil temperatures and water potential in the greenhouse were in the range of the fungus. However, soil receptivity was lower in greenhouse soil, irrespective of sterilisation, than in sterilised sand. Plant resistance was the only factor able to suppress nematode densities, disease severity and yield losses, and to protect the following cucumber crop. Environmental factors involved in soil receptivity could have negatively affected fungus effectiveness. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Effect of reflective surfaces on a greenhouse lettuce crop

Energy Technology Data Exchange (ETDEWEB)

Warman, P.R.; Mayhew, W.J.

1979-01-01

The Canadian greenhouse industry is an important segment of horticultural production, providing employment for thousands of people. Continuing increases in the costs of conventional fuel supplies, however, has placed the industry in some jeopardy since the cost of heating during the winter months is also escalating. In response to this problem the Brace Research Institute has developed a single roofed greenhouse designed to capture and store the sun's energy, and to increase the amount of downward solar radiation inside the greenhouse through the use of specularly-reflecting back and side walls. The research investigated the effect of a reflective surface on plant growth, development, and nutritional uptake during fall and the early months of winter. The inside walls of the greenhouse were lined with aluminized polyester to act as a reflective surface and flat black roofing felt paper to provide a non-reflecting surface. Grand Rapids Forcing lettuce was planted from seed into a peat-vermiculite bed and total solar radiation was monitored on the horizontal. Over the duration of the experiment, the reflective side of the greenhouse received more than twice as much solar radiation as the non-reflective side leading to significantly larger plant yields on the reflective side. There were no significant differences in the uptake of the plant macronutrients, N, P, K, Ca, and Mg.

Photovoltaic greenhouses: evaluation of shading effect and its influence on agricultural performances

Directory of Open Access Journals (Sweden)

Sergio Castellano

2014-12-01

Full Text Available During the last years, European government remuneration polices promoted the realisation of photovoltaic systems integrated with the structures instead of on ground photovoltaic (PV plants. In this context, in rural areas, greenhouses covered with PV modules have been developed. In order to interdict the building of greenhouses with an amount of opaque panels on covering not coherent with the plant production, local laws assigned a threshold value, usually between 25% and 50%, of the projection on the soil of the roof. These ranges seem not to be based on scientific evaluation about the agricultural performances required to the building but only on empirical assessments. Purpose of this paper is to contribute to better understand the effect of different configurations of PV panels on the covering of a monospan duo-pitched roof greenhouse in terms of shading effect and energy efficiency during different periods of the year. At this aim, daylighting and insolation analysis were performed by means of the software Autodesk® Ecotect® Analysis (Autodesk, Inc., San Rafael, CA, USA on greenhouse model with different covering ratio of polycrystalline photovoltaic panels on the roof.

Potato (Solanum tuberosum) greenhouse tuber production as an assay for asexual reproduction effects from herbicides

Science.gov (United States)

The present study determined whether young potato plants can be used as an assay to indicate potential effects of pesticides on asexual reproduction. Solanum tuberosum (Russet Burbank) plants were grown from seed pieces in a mineral soil in pots under greenhouse conditions. Plant...

Potentials and drawbacks of chelate-enhanced phytoremediation of soils

NARCIS (Netherlands)

Römkens, P.F.A.M.; Bouwman, L.A.; Japenga, J.; Draaisma, C.

2002-01-01

Chelate-enhanced phytoremediation has been proposed as an effective tool for the extraction of heavy metals from soils by plants. However, side-effects related to the addition of chelates, e.g. metal leaching and effects on soil micro-organisms, were usually neglected. Therefore, greenhouse and

Grappling with greenhouse

International Nuclear Information System (INIS)

Mitchell, C.D.

1992-01-01

A natural greenhouse effect keeps the Earth at a temperature suitable for life. Some of the gases responsible for the greenhouse effect are increasing at an unprecedented rate because of human activity. These increased levels of greenhouse gases in the atmosphere will strengthen the natural greenhouse effect, leading to an overall warming of the Earth's surface. Global warming resulting from the enhanced greenhouse effect is likely to be obscured by normal climatic fluctuations for another ten years or more. The extent of human-caused climate change will depend largely on future concentrations of greenhouse gases in the atmosphere. In turn, the composition of the atmosphere depends on the release of greenhouse gases. Releases are hard to predict, because they require an understanding of future human activity. The composition of the atmosphere also depends on the processes which remove greenhouse gases from it. This booklet is summarizing the latest research results in the form of climate change scenarios. The present scenarios of change are based on climate models, together with an understanding of how present-day climate, with its inherent natural variability, affects human activities. These scenarios present a coherent range of future possibilities for climate; they are not predictions but they serve as a useful starting point. It is estimated that human-caused climate change will affect all aspects of life in Australia, including our cities, agriculture, pests and diseases, fisheries and natural ecosystems. 15 figs., ills

Global warming potential and greenhouse gas emission under different soil nutrient management practices in soybean-wheat system of central India.

Science.gov (United States)

Lenka, Sangeeta; Lenka, Narendra Kumar; Singh, Amar Bahadur; Singh, B; Raghuwanshi, Jyothi

2017-02-01

Soil nutrient management is a key component contributing to the greenhouse gas (GHG) flux and mitigation potential of agricultural production systems. However, the effect of soil nutrient management practices on GHG flux and global warming potential (GWP) is less understood in agricultural soils of India. The present study was conducted to compare three nutrient management systems practiced for nine consecutive years in a soybean-wheat cropping system in the Vertisols of India, in terms of GHG flux and GWP. The treatments were composed of 100% organic (ONM), 100% inorganic (NPK), and integrated nutrient management (INM) with 50% organic + 50% inorganic inputs. The gas samples for GHGs (CO 2 , CH 4 , and N 2 O) were collected by static chamber method at about 15-day interval during 2012-13 growing season. The change in soil organic carbon (SOC) content was estimated in terms of the changes in SOC stock in the 0-15 cm soil over the 9-year period covering 2004 to 2013. There was a net uptake of CH 4 in all the treatments in both soybean and wheat crop seasons. The cumulative N 2 O and CO 2 emissions were in the order of INM > ONM > NPK with significant difference between treatments (p < 0.05) in both the crop seasons. The annual GWP, expressed in terms of CH 4 and N 2 O emission, also followed the same trend and was estimated to be 1126, 1002, and 896 kg CO 2 eq ha -1  year -1 under INM, ONM, and NPK treatments, respectively. However, the change in SOC stock was significantly higher under ONM (1250 kg ha -1  year -1 ) followed by INM (417 kg ha -1  year -1 ) and least under NPK (198 kg ha -1  year -1 ) treatment. The wheat equivalent yield was similar under ONM and INM treatments and was significantly lower under NPK treatment. Thus, the GWP per unit grain yield was lower under ONM followed by NPK and INM treatments and varied from 250, 261, and 307 kg CO 2 eq Mg -1 grain yield under ONM, NPK, and INM treatments, respectively.

Study of greenhouse gases reduction alternatives for the exploitation of non conventional oil sands in Canada

Energy Technology Data Exchange (ETDEWEB)

Bouchonneau, Deborah [Institut Francais du Petrole (IFP), Paris (France)

2008-07-01

High energy prices and greenhouse gases reduction represent the main challenges the current worldwide energetic situation has to face. As a consequence, paradox strategies can be highlighted: oil prices are sufficiently high to exploit non conventional oil resources, like extra heavy oils and oil sands. But the production of these resources emits larger GHG than the conventional oil path and implies other major environmental issues (water management, risks of soil pollution, destruction of the boreal forest), incompatible with the rules validated by the protocol of Kyoto. At the light of the new greenhouse gases reduction regulation framework announced by the Canadian Federal government, this work focuses on the study of greenhouse gases reduction alternatives applied to the non conventional oil sands exploitation in Canada. (author)

Investigation of the behaviour of pesticides in soil environment by using isotope tracer techniques. Part of a coordinated programme on isotope-tracer-aided studies of agrochemical residue - soil biota interactions

International Nuclear Information System (INIS)

Onal, G.

1982-07-01

Studies were conducted to characterize the behaviour of 14 C-carboxyl-labelled 2,4-D (2,4-dichlorophenoxy acetic acid) in soil-plant systems under laboratory, greenhouse and field conditions. Results indicated that degradation, of the chemical was faster in soil rich in organic matter and that moisture content did not affect degradation rates significantly. Under greenhouse conditions, barley, wheat and oat plants took up less than 1% of the amount of herbicide applied to soil. Under field conditions, 15% of the applied 14 C-activity was recovered in soil-methanol extracts prepared by Soxhlet extractor for 48 hours. Soil radioactivity, remaining after extraction, was determined by a wet combustion procedure and was found to account for 48% of the applied herbicide after four weeks. The balance of 37% was presumably lost as 14 C-carbon dioxide

Variability in soil-water retention properties and implications for physics-based simulation of landslide early warning criteria

Science.gov (United States)

Thomas, Matthew A.; Mirus, Benjamin B.; Collins, Brian D.; Lu, Ning; Godt, Jonathan W.

2018-01-01

Rainfall-induced shallow landsliding is a persistent hazard to human life and property. Despite the observed connection between infiltration through the unsaturated zone and shallow landslide initiation, there is considerable uncertainty in how estimates of unsaturated soil-water retention properties affect slope stability assessment. This source of uncertainty is critical to evaluating the utility of physics-based hydrologic modeling as a tool for landslide early warning. We employ a numerical model of variably saturated groundwater flow parameterized with an ensemble of texture-, laboratory-, and field-based estimates of soil-water retention properties for an extensively monitored landslide-prone site in the San Francisco Bay Area, CA, USA. Simulations of soil-water content, pore-water pressure, and the resultant factor of safety show considerable variability across and within these different parameter estimation techniques. In particular, we demonstrate that with the same permeability structure imposed across all simulations, the variability in soil-water retention properties strongly influences predictions of positive pore-water pressure coincident with widespread shallow landsliding. We also find that the ensemble of soil-water retention properties imposes an order-of-magnitude and nearly two-fold variability in seasonal and event-scale landslide susceptibility, respectively. Despite the reduced factor of safety uncertainty during wet conditions, parameters that control the dry end of the soil-water retention function markedly impact the ability of a hydrologic model to capture soil-water content dynamics observed in the field. These results suggest that variability in soil-water retention properties should be considered for objective physics-based simulation of landslide early warning criteria.

A greenhouse study on arsenic remediation potential of Vetiver grass (Vetiveria Zizanioides) as a function of soil physico-chemical properties

Science.gov (United States)

Quispe, M. A.; Datta, R.; Sarkar, D.; Sharma, S.

2006-05-01

Arsenic is one of the most harmful and toxic metals, being a Group A human carcinogen. Mining activities as well as the use of arsenic-containing pesticides have resulted in the contamination of a wide variety of sites including mine tailings, cattle dip sites, wood treatment sites, pesticide treatment areas, golf courses, etc. Phytoremediation has emerged as a novel and promising technology, which uses plants to clean up contaminated soil and water taking advantage of plant's natural abilities to extract and accumulate various contaminants. This method has distinct advantages, since it maintains the biological properties and physical structure of the soil, is environment friendly, and above all, inexpensive. However, effective remediation of contaminated residential soils using a specific plant species is an immensely complex task whose success depends on a multitude of factors including the ability of the target plant to uptake, translocate, detoxify, and accumulate arsenic in its system. One of the major challenges in phytoremediation lies in identifying a fast- growing, high biomass plant that can accumulate the contaminant in its harvestable parts. vetiver grass (Vetiveria zizanioides) is a fast-growing perennial grass with strong ecological adaptability and large biomass. While this plant is not a hyperaccumulator of arsenic, it has been reported to be able to tolerate and accumulate considerable amounts of arsenic. Being a high biomass, fast-growing plant, vetiver has the potential to be used for arsenic remediation. The present study investigates the potential of vetiver grass to tolerate and accumulate arsenic in soils with varying physico-chemical properties. A greenhouse study is in progress to study the uptake, tolerance and stress response of vetiver grass to inorganic arsenical pesticide. A column study was set up using 5 soils (Eufaula, Millhopper, Orelia, Orla, and Pahokee Muck) contaminated with sodium arsenite at 4 different concentrations of

Regional greenhouse gas emissions from cultivation of winter wheat and winter rapeseed for biofuels in Denmark

DEFF Research Database (Denmark)

Elsgaard, Lars; Olesen, Jørgen E; Hermansen, John Erik

2013-01-01

Biofuels from bioenergy crops may substitute a significant part of fossil fuels in the transport sector where, e.g., the European Union has set a target of using 10% renewable energy by 2020. Savings of greenhouse gas emissions by biofuels vary according to cropping systems and are influenced...... by such regional factors as soil conditions, climate and input of agrochemicals. Here we analysed at a regional scale the greenhouse gas (GHG) emissions associated with cultivation of winter wheat for bioethanol and winter rapeseed for rapeseed methyl ester (RME) under Danish conditions. Emitted CO2 equivalents...

Fate of 14C-allylalcohol herbicide in soils and crop residues

International Nuclear Information System (INIS)

Scheunert, I.; Vockel, D.; Klein, W.; Korte, F.

1981-01-01

Residue disappearance and leaching of 14 C-allylalcohol from different soils were studied in laboratory experiments. Additionally, the uptake of residues by lettuce and carrots was investigated in the greenhouse. In laboratory experiments, residue disappearance and leaching from soils was correlated negatively to the organic matter content. In greenhouse experiments with a sandy loam soil at an application rate normally used in practice, an average of 12.5% of the applied radioactivity was recovered after an eight day interval between application and sowing. Furthermore, an average of 8% (sum in soil and plants) of the applied radioactivity was recovered after lettuce or carrot growing. Uptake of residues was higher by carrots than by lettuce, and higher by lettuce roots than by lettuce tops. No bioaccumulation was observed. The residues in soils and plants were, to a high percent-age, unextractable and, to a smaller extent, fully water-soluble products. Unchanged allylalcohol could not be detected by the analytical methods used

Feasibility of Using Phytoextraction to Remediate a Compost-Based Soil Contaminated with Cadmium.

Science.gov (United States)

Parisien, Michele A; Rutter, Allison; Zeeb, Barbara A

2015-01-01

Greenhouse and in-situ field experiments were used to determine the potential for phytoextraction to remediate soil contaminated with Cd from municipal solid waste (MSW) and sewage sludge (SS) compost application at a Peterborough (Canada) site. For the greenhouse experiment, one native (Chenopodium album) and three naturalized (Poa compressa, Brassica juncea, Helianthus annuus) plant species were planted in soil containing no detectable Cd (phytoextraction is therefore not feasible at this site. Though low Cd bioavailability has negative implications for Cd phytoextraction from MSW/SS compost-based soils, it may limit receptor exposure to Cd sufficiently to eliminate the potential for risk at this site.

Detection of DNA specific sequences of Spongospora subterranea in soil and potato tubers

Directory of Open Access Journals (Sweden)

Cristian Oswaldo Saavedra Rodríguez

2004-01-01

Full Text Available A test has been developed for early identification of the casual agent for potato powdery scab (Spongospora subterranea fs subterranea. Identification was carried out in seeds and soil where this tuber is grown. A polymerase chain reaction (PCR was set up for detecting 372, 390 and 391 bp ribosomal DNA internal transcribed spacer sequences (ITS in the S. subterraneagenome. A method for extracting and purifying DNA from infected plant material (potato root nodes and pustules on the potato was standardised. Plant tissue was obtained by potato tuber propagation using an inoculum from the pathogen in greenhouse conditions. After the PCR had been optimised and its sensitivity determined, a molecular methodology was validated by examining plant material infected with S. subterranea and soil samples infested with the pathogen obtained from the departments of Cundinamarca and Nariño. The PCR detected S. subterranea DNA from infected material and soil samples (all thirty samples from the experimental area analysed proved PCR positive. These results show that this molecular method was not just useful for the early detection of the pathogen in soil samples but as a tool for detecting or determining the possible presence of this micro-organism in places that have been declared f ree of S. subterranea and an effective form of quality control in producing the certif ied potato seed. Key words: Powdery scab, cystosori, internal transcribed spacer, PCR, plasmodiophorid.

Evaluation of crop residues on potassium kinetics in an acid soil and potassium use efficiency in potato-garlic sequence using tracer 86Rb

International Nuclear Information System (INIS)

Sud, K.C.

2005-01-01

Greenhouse and laboratory studies were conducted on an acid soil in order to evaluate the role of two crop residues i.e. paddy and wheat along with farmyard manure on potassium kinetics and its availability in the potato-garlic sequence using tracer 86 Rb. Under rapid equilibrium, application of crop residues of paddy, wheat straw and FYM were able to enhance soil pH and organic carbon content. In addition, their application helped in enhancing soil K availability indices like water soluble, available and non-exchangeable -K. This was further augmented by the Q/I studies using 86 Rb where application of organic residues helped in lowering the potassium buffering capacity of the soil. Greenhouse study supplemented the results obtained from laboratory study where application of crop residues/FYM were able to improve the potato yield significantly and maintained higher concentration of K in potato leaf at early growth stages. A significant correlation was obtained between leaf K and haulms-K with that of 86 Rb activities in potato leaf at 35 days and 86 Rb absorbed in the haulms, respectively. Residues/ FYM and PK application to potato left sufficient residual effect on succeeding garlic crop. In potato-garlic sequence, K recovery was highest with FYM while N and P recoveries were higher with wheat residues. The nutrient recoveries with PK application followed law of diminishing returns. (author)

The impact of land-use change from forest to oil palm on soil greenhouse gas and volatile organic compound fluxes in Malaysian Borneo

Science.gov (United States)

Drewer, Julia; Leduning, Melissa; Kerdraon-Byrne, Deirdre; Sayer, Emma; Sentien, Justin; Skiba, Ute

2017-04-01

Monocultures of oil palm have expanded in SE Asia, and more recently also in Africa and South America, frequently replacing tropical forests. The limited data available clearly show that this conversion is associated with a potentially large greenhouse gas (GHG) burden. The physical process of land-use change, such is felling, drainage and ploughing can significantly increase emissions of N2O and soil CO2 respiration and decrease CH4 oxidation rates in the short term; and in the long-term regular nitrogen applications will impact in particular soil N2O fluxes. Little is known about volatile organic compound (VOC) fluxes from soil and litter in tropical forests and their speciation or about the links between GHG and VOC fluxes. VOC emissions are important as they directly and indirectly influence the concentrations and lifetimes of air pollutants and GHGs. For example, oxidation of VOCs generate tropospheric ozone which is also a potent GHG. Within ecosystems, monoterpenes can mediate plant-microbe and plant- interactions and protect photosynthesis during abiotic stress. However, little is known about monoterpene composition in the tropics - a widely recognized major global source of terpenoids to the atmosphere. These knowledge gaps make it difficult for developing countries in the tropics, especially SE Asia, to develop effective mitigation strategies. Current understanding of soil GHG fluxes associated with land-use change from forest to oil palm is not sufficient to provide reliable estimates of their carbon footprints and sustainability or advice on GHG mitigation strategies. To provide the necessary data we have installed a total of 56 flux chambers in logged forests, forest fragments and mature and young oil palm plantations as well as riparian zones within the SAFE landscape in SE Sabah (Stability of Altered Forest Ecosystems; http://www.safeproject.net). Soil respiration rates, N2O, CH4 and VOC fluxes together with soil moisture, pH, mineral and total C and

The Effect of Earthworm (Lumbricus terrestris L.) Population Density and Soil Water Content Interactions on Nitrous Oxide Emissions from Agricultural Soils

International Nuclear Information System (INIS)

Evers, A.K.; Gordon, A.M.; Thevathasan, N.V.; Demers, T.A.

2010-01-01

Earthworms may have an influence on the production of N 2 O, a greenhouse gas, as a result of the ideal environment contained in their gut and casts for denitrifier bacteria. The objective of this study was to determine the relationship between earthworm (Lumbricus terrestris L.) population density, soil water content and N 2 O emissions in a controlled greenhouse experiment based on population densities (90 to 270 individuals m-2) found at the Guelph Agroforestry Research Station (GARS) from 1997 to 1998. An experiment conducted at considerably higher than normal densities of earthworms revealed a significant relationship between earthworm density, soil water content and N 2 O emissions, with mean emissions increasing to 43.5 g ha-1day-1 at 30 earthworms 0.0333 m-2 at 35% soil water content. However, a second experiment, based on the density of earthworms at GARS, found no significant difference in N 2 O emissions (5.49 to 6.99 g ha-1day-1) aa a result of density and 31% soil water content

Chapter 14. Greenhouses

Energy Technology Data Exchange (ETDEWEB)

Rafferty, Kevin D.

1998-01-01

Greenhouse heating is one of the most common uses of geothermal resources. Because of the significant heating requirements of greenhouses and their ability to use very low- temperature fluids, they are a natural application. The evaluation of a particular greenhouse project involves consideration of the structure heating requirements, and the system to meet those requirements. This chapter is intended to provide information on each of these areas.

Uncertainty analysis of a coupled ecosystem response model simulating greenhouse gas fluxes from a temperate grassland

Science.gov (United States)

Liebermann, Ralf; Kraft, Philipp; Houska, Tobias; Breuer, Lutz; Müller, Christoph; Kraus, David; Haas, Edwin; Klatt, Steffen

2015-04-01

Among anthropogenic greenhouse gas emissions, CO2 is the dominant driver of global climate change. Next to its direct impact on the radiation budget, it also affects the climate system by triggering feedback mechanisms in terrestrial ecosystems. Such mechanisms - like stimulated photosynthesis, increased root exudations and reduced stomatal transpiration - influence both the input and the turnover of carbon and nitrogen compounds in the soil. The stabilization and decomposition of these compounds determines how increasing CO2 concentrations change the terrestrial trace gas emissions, especially CO2, N2O and CH4. To assess the potential reaction of terrestrial greenhouse gas emissions to rising tropospheric CO2 concentration, we make use of a comprehensive ecosystem model integrating known processes and fluxes of the carbon-nitrogen cycle in soil, vegetation and water. We apply a state-of-the-art ecosystem model with measurements from a long term field experiment of CO2 enrichment. The model - a grassland realization of LandscapeDNDC - simulates soil chemistry coupled with plant physiology, microclimate and hydrology. The data - comprising biomass, greenhouse gas emissions, management practices and soil properties - has been attained from a FACE (Free Air Carbon dioxide Enrichment) experiment running since 1997 on a temperate grassland in Giessen, Germany. Management and soil data, together with weather records, are used to drive the model, while cut biomass as well as CO2 and N2O emissions are used for calibration and validation. Starting with control data from installations without CO2 enhancement, we begin with a GLUE (General Likelihood Uncertainty Estimation) assessment using Latin Hypercube to reduce the range of the model parameters. This is followed by a detailed sensitivity analysis, the application of DREAM-ZS for model calibration, and an estimation of the effect of input uncertainty on the simulation results. Since first results indicate problems with

Application of dynamic model to predict some inside environment variables in a semi-solar greenhouse

Directory of Open Access Journals (Sweden)

Behzad Mohammadi

2018-06-01

Full Text Available Greenhouses are one of the most effective cultivation methods with a yield per cultivated area up to 10 times more than free land cultivation but the use of fossil fuels in this production field is very high. The greenhouse environment is an uncertain nonlinear system which classical modeling methods have some problems to solve it. There are many control methods, such as adaptive, feedback and intelligent control and they require a precise model. Therefore, many modeling methods have been proposed for this purpose; including physical, transfer function and black-box modeling. The objective of this paper is to modeling and experimental validation of some inside environment variables in an innovative greenhouse structure (semi-solar greenhouse. For this propose, a semi-solar greenhouse was designed and constructed at the North-West of Iran in Azerbaijan Province (38°10′N and 46°18′E with elevation of 1364 m above the sea level. The main inside environment factors include inside air temperature (Ta and inside soil temperature (Ts were collected as the experimental data samples. The dynamic heat transfer model used to estimate the temperature in two different points of semi-solar greenhouse with initial values. The results showed that dynamic model can predict the inside temperatures in two different points (Ta and Ts with RMSE, MAPE and EF about 5.3 °C, 10.2% and 0.78% and 3.45 °C, 7.7% and 0.86%, respectively. Keywords: Semi-solar greenhouse, Dynamic model, Commercial greenhouse

Soil moisture content with global warming

International Nuclear Information System (INIS)

Vinnikov, K.Ya.

1990-01-01

The potential greenhouse-gas-induced changes in soil moisture, particularly the desiccation of the Northern Hemisphere contents in summer, are discussed. To check the conclusions based on climate models the authors have used long-term measurements of contemporary soil moisture in the USSR and reconstructions of soil moisture for the last two epochs that were warmer than the present, namely, the Holocene optimum, 5,000-6,000 years ago, and the last interglacial, about 125,000 years ago. The analysis shows that there is a considerable disagreement between the model results and the empirical data

Storage of Miscanthus-derived carbon in rhizomes, roots, and soil

DEFF Research Database (Denmark)

Christensen, Bent Tolstrup; Lærke, Poul Erik; Jørgensen, Uffe

2016-01-01

Compared with annual crops, dedicated perennial bioenergy crops are ascribed additional benefits in terms of reduced greenhouse gas emissions; these benefits include increased carbon (C) storage in soil. We measured Miscanthus-derived C in rhizomes, roots, and 0–100 cm soil beneath three 16-yr-ol...

Effects of biochar and elevated soil temperature on soil microbial activity and abundance in an agricultural system

Science.gov (United States)

Bamminger, Chris; Poll, Christian; Marhan, Sven

2014-05-01

As a consequence of Global Warming, rising surface temperatures will likely cause increased soil temperatures. Soil warming has already been shown to, at least temporarily, increase microbial activity and, therefore, the emissions of greenhouse gases like CO2 and N2O. This underlines the need for methods to stabilize soil organic matter and to prevent further boost of the greenhouse gas effect. Plant-derived biochar as a soil amendment could be a valuable tool to capture CO2 from the atmosphere and sequestrate it in soil on the long-term. During the process of pyrolysis, plant biomass is heated in an oxygen-low atmosphere producing the highly stable solid matter biochar. Biochar is generally stable against microbial degradation due to its chemical structure and it, therefore, persists in soil for long periods. Previous experiments indicated that biochar improves or changes several physical or chemical soil traits such as water holding capacity, cation exchange capacity or soil structure, but also biotic properties like microbial activity/abundance, greenhouse gas emissions and plant growth. Changes in the soil microbial abundance and community composition alter their metabolism, but likely also affect plant productivity. The interaction of biochar addition and soil temperature increase on soil microbial properties and plant growth was yet not investigated on the field scale. To investigate whether warming could change biochar effects in soil, we conducted a field experiment attached to a soil warming experiment on an agricultural experimental site near the University of Hohenheim, already running since July 2008. The biochar field experiment was set up as two-factorial randomized block design (n=4) with the factors biochar amendment (0, 30 t ha-1) and soil temperature (ambient, elevated=ambient +2.5° C) starting from August 2013. Each plot has a dimension of 1x1m and is equipped with combined soil temperature and moisture sensors. Slow pyrolysis biochar from the C

Comparison the Efficiency of Aquasorb and Accepta Superabsorbent Polymers in Improving Physical, Chemical, and Biological Properties of Soil and Tomato Turnover under Greenhouse Condition

Directory of Open Access Journals (Sweden)

mehdi nourzadeh haddad

2017-06-01

condition of soil improving the crop production finally. Material and Methods: This experiment was conducted under greenhouse conditions in Shushtar city at northern Khuzestan Province using the randomized complete block design using 13 treatments and with 3 replications. Soil samples were taken from a field in the study area, air dried, and passed through a 2 mm sieve. Seven concentration (0, 0.25, 0.5, 0.75, 1.0, 1.25, and 1.5 percentage of superabsorbent polymers (Aquasorb and Accepta were used in greenhouse condition. Superabsorbent and 10 Kg soil thoroughly mixed in each pot. All treatments were irrigated when the plants at control showed sign of wilting. There were three replications of each treatment. NPK fertilizers were applied as urea, diammonium phosphate (DAP and potassium sulphate (K2SO4 based the soil test. Soil samples were again collected which were analyzed for nitrate-N, total organic carbon (TOC, phosphorus and potassium, bulk density, particle density and saturation percentage.NPK of plant samples were also determined. Data were statistically analysed by Duncan test using SPSS. Results and Discussion: Results had shown that the highest bulk density (1.515 gr/cm3 seen in control treatment and with increasing the polymer, bulk density decreased significantly to 0.91 gr/cm3 in treatment No.2. Also the treatments No. 4 and 11 shown decreasing EC significantly from 0.9 in control treatment to 0.68 in No.4. Adding superabsorbent had significant effect on Potassium amount of soil. Using superabsorbent had no significant effect on real density, pH, N amount, Phosphorous, soil organic carbon after yield harvesting in soil and amount of Phosphorous in plant. Significant increasing in number of leaves, branches, fresh weight of plant, and fruit weight with using superabsorbent polymers and the highest used polymer level (treatments No. 7 and 13 had the highest effect on fresh weight of plant which reported 47.2 g for No.7 and 90.47 g for No.13. Also using 1

Uptake of plutonium, americium, curium, and neptunium in plants cultivated under greenhouse conditions

International Nuclear Information System (INIS)

Pimpl, M.; Schmidt, W.

1984-01-01

The root-uptake of Np, Pu, Am, and Cm from three different artificially contaminated soils in grass, maize, spring wheat, and potatoes was investigated under greenhouse conditions in pots filled with 9 kg contaminated soil and in lysimeters with a surface area of 0,5 m 2 containing the soils in undisturbed profils up to a depth of 80 cm. Only the plough layer of 30 cm was contaminated with Np, Pu, Am, and Cm. Crop cultivation was done corresponding to usual practice in agriculture. Results of the 1st vegetation period are represented. Transfer factors obtained deviate considerably from those which are recommended for the estimation of long-term exposure of man in the Federal Republic of Germany. (orig.)

Greenhouse gas emissions and sinks in the Swedish forest industry; Svenska skogsindustrins emissioner och upptag av vaexthusgaser

Energy Technology Data Exchange (ETDEWEB)

Hagberg, Linus; Karlsson, Per-Erik; Stripple, Haakan; Ek, Mats; Zetterberg, Therese; Zetterberg, Lars

2008-06-15

In this study, the greenhouse gas uptake and emissions are estimated for activities associated with the Swedish forest industry. The study is intended as an update of a previous emission inventory from 1994. The inventory includes uptake and emissions of carbon dioxide (CO{sub 2}), nitrous oxide (N{sub 2}O) and methane (CH{sub 4}) in the forest ecosystem (all productive forest land in Sweden) and in the forest industrial production system, which here includes forestry and logging, manufacturing industries (pulp and paper industry, the sawmill industry and board industry), and transport of forest raw material and forest products in Sweden. The study shows that the overall net result of the Swedish forest industry activities is an annual removals of greenhouse gases equivalent to 1.6 million tonnes of CO{sub 2} equivalents. The result is however beset with considerable uncertainties, especially with regard to changes in carbon stocks in the forest ecosystem. The overall results of the calculations are also dependent on how forest industry activities delineated. The study shows that the issues in the forest industrial production system has decreased by about 40% since the early 1990s from the equivalent 5.8 million tonnes CO{sub 2} equivalents to 3.5 million tonnes of CO{sub 2} equivalent, despite increased production. The study also shows that the forest industry total contributions to the Swedish forest constitutes a net sink of greenhouse gases, which we estimated at 5.2 million tonnes of CO{sub 2} equivalents. This is due primarily to a continued net growth in the Swedish forest, which is the result of an active and sustainable Forestry. Most of the forest land represents a significant lowering of CO{sub 2}, while the organogenic soils, which accounts for a smaller proportion of forest areas, probably account for a significant emission of CO{sub 2}. Above all, included in the calculations of gas exchange in the forest ecosystem, is a large emission of CO{sub 2

NEW GREENHOUSE TECHNOLOGIES FOR VEGETABLE PRODUCTION

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S. M. Sirota

2016-01-01

Full Text Available First decade of XXI century is characterized by significant augmentation in vegetable world’s production. Average annual vegetable production has been 346 million tons, and it has exceeded the average annual potato production (318 million tons. It has occurred due to the use of up-to-date technologies for vegetable production and, particularly, in greenhouses. In Russian Federation, the total production of vegetables was 5 275.6 thousand tons in 2015 that was 13.3% more than in 2014. But the total vegetable production in greenhouses was only 722.8 thousand tons, that was 0.7% less than in 2014 (728.1 thousand tons. It can be explained that the old technologies have been used for many greenhouses around Russia. Up-to-date technologies for greenhouses are described in the article. Small-volume hydroponics. Plants are grown in mineral wadding, packed up in the special chutes. Mineral nutrition and water are supplied through special pipe with many branch pipes toward each plant. Advantage: pH and nutrition are maintained, consumption of water and mineral nutrition are optimized, and that improves plants grow control. Expenditures of labor decreased, quality of fruit became better and the yield increased significantly by 45-50 kg/m2 comparing with growing on the soil (25-30 kg/m2. Hydroponics with flowing water (salad production lines. Conveyor for salad and vegetable growing on horizontal moving chutes with flowing water and nutrition was developed. Advantage: high level of automation and mechanization of all processes of growing increased the effectiveness of the use of greenhouse areas (we can place 30% plants more at the same area. Seedling production lines. Production lines for seedlings enable to grow vegetables and leafy vegetables on stationary benches, being furnished with periodical nutrition and water supply at times. Advantage: 700 seedlings additionally on each m2 a year. Future technologies are

PHYTOREMEDIATION OF SOILS CONTAMINATED WITH WOOD PRESERVATIVES: GREENHOUSE AND FIELD EVALUATIONS

Science.gov (United States)

Phytoremediation was evaluated as a potential treatment for the creosote-contaminated surface soil at the McCormick and Baxter (M&B) Superfund Site in Portland, OR. Soil a the M&B site is contaminated with pentachlorophenol (PCP) and polyaromatic hydrocarbons (PAHs). Eight indivi...

Early Eocene deep-sea benthic foraminiferal faunas: Recovery from the Paleocene Eocene Thermal Maximum extinction in a greenhouse world

Science.gov (United States)

Thomas, Ellen; D’haenens, Simon; Speijer, Robert P.; Alegret, Laia

2018-01-01

The early Eocene greenhouse world was marked by multiple transient hyperthermal events. The most extreme was the Paleocene-Eocene Thermal Maximum (PETM, ~56 Ma), linked to the extinction of the globally recognised deep-sea benthic foraminiferal Velasco fauna, which led to the development of early Eocene assemblages. This turnover has been studied at high resolution, but faunal development into the later early Eocene is poorly documented. There is no widely accepted early Eocene equivalent of the Late Cretaceous-Paleocene Velasco fauna, mainly due to the use of different taxonomic concepts. We compiled Ypresian benthic foraminiferal data from 17 middle bathyal-lower abyssal ocean drilling sites in the Pacific, Atlantic and Indian Oceans, in order to characterise early Eocene deep-sea faunas by comparing assemblages across space, paleodepth and time. Nuttallides truempyi, Oridorsalis umbonatus, Bulimina trinitatensis, the Bulimina simplex group, the Anomalinoides spissiformis group, pleurostomellids, uniserial lagenids, stilostomellids and lenticulinids were ubiquitous during the early Eocene (lower-middle Ypresian). Aragonia aragonensis, the Globocassidulina subglobosa group, the Cibicidoides eocaenus group and polymorphinids became ubiquitous during the middle Ypresian. The most abundant early Ypresian taxa were tolerant to stressed or disturbed environments, either by opportunistic behavior (Quadrimorphina profunda, Tappanina selmensis, Siphogenerinoides brevispinosa) and/or the ability to calcify in carbonate-corrosive waters (N. truempyi). Nuttallides truempyi, T. selmensis and other buliminids (Bolivinoides cf. decoratus group, Bulimina virginiana) were markedly abundant during the middle Ypresian. Contrary to the long-lived, highly diverse and equitable Velasco fauna, common and abundant taxa reflect highly perturbed assemblages through the earliest Ypresian, with lower diversity and equitability following the PETM extinction. In contrast, the middle Ypresian

Early Eocene deep-sea benthic foraminiferal faunas: Recovery from the Paleocene Eocene Thermal Maximum extinction in a greenhouse world.

Directory of Open Access Journals (Sweden)

Gabriela J Arreguín-Rodríguez

Full Text Available The early Eocene greenhouse world was marked by multiple transient hyperthermal events. The most extreme was the Paleocene-Eocene Thermal Maximum (PETM, ~56 Ma, linked to the extinction of the globally recognised deep-sea benthic foraminiferal Velasco fauna, which led to the development of early Eocene assemblages. This turnover has been studied at high resolution, but faunal development into the later early Eocene is poorly documented. There is no widely accepted early Eocene equivalent of the Late Cretaceous-Paleocene Velasco fauna, mainly due to the use of different taxonomic concepts. We compiled Ypresian benthic foraminiferal data from 17 middle bathyal-lower abyssal ocean drilling sites in the Pacific, Atlantic and Indian Oceans, in order to characterise early Eocene deep-sea faunas by comparing assemblages across space, paleodepth and time. Nuttallides truempyi, Oridorsalis umbonatus, Bulimina trinitatensis, the Bulimina simplex group, the Anomalinoides spissiformis group, pleurostomellids, uniserial lagenids, stilostomellids and lenticulinids were ubiquitous during the early Eocene (lower-middle Ypresian. Aragonia aragonensis, the Globocassidulina subglobosa group, the Cibicidoides eocaenus group and polymorphinids became ubiquitous during the middle Ypresian. The most abundant early Ypresian taxa were tolerant to stressed or disturbed environments, either by opportunistic behavior (Quadrimorphina profunda, Tappanina selmensis, Siphogenerinoides brevispinosa and/or the ability to calcify in carbonate-corrosive waters (N. truempyi. Nuttallides truempyi, T. selmensis and other buliminids (Bolivinoides cf. decoratus group, Bulimina virginiana were markedly abundant during the middle Ypresian. Contrary to the long-lived, highly diverse and equitable Velasco fauna, common and abundant taxa reflect highly perturbed assemblages through the earliest Ypresian, with lower diversity and equitability following the PETM extinction. In contrast, the

Early Eocene deep-sea benthic foraminiferal faunas: Recovery from the Paleocene Eocene Thermal Maximum extinction in a greenhouse world.

Science.gov (United States)

Arreguín-Rodríguez, Gabriela J; Thomas, Ellen; D'haenens, Simon; Speijer, Robert P; Alegret, Laia

2018-01-01

The early Eocene greenhouse world was marked by multiple transient hyperthermal events. The most extreme was the Paleocene-Eocene Thermal Maximum (PETM, ~56 Ma), linked to the extinction of the globally recognised deep-sea benthic foraminiferal Velasco fauna, which led to the development of early Eocene assemblages. This turnover has been studied at high resolution, but faunal development into the later early Eocene is poorly documented. There is no widely accepted early Eocene equivalent of the Late Cretaceous-Paleocene Velasco fauna, mainly due to the use of different taxonomic concepts. We compiled Ypresian benthic foraminiferal data from 17 middle bathyal-lower abyssal ocean drilling sites in the Pacific, Atlantic and Indian Oceans, in order to characterise early Eocene deep-sea faunas by comparing assemblages across space, paleodepth and time. Nuttallides truempyi, Oridorsalis umbonatus, Bulimina trinitatensis, the Bulimina simplex group, the Anomalinoides spissiformis group, pleurostomellids, uniserial lagenids, stilostomellids and lenticulinids were ubiquitous during the early Eocene (lower-middle Ypresian). Aragonia aragonensis, the Globocassidulina subglobosa group, the Cibicidoides eocaenus group and polymorphinids became ubiquitous during the middle Ypresian. The most abundant early Ypresian taxa were tolerant to stressed or disturbed environments, either by opportunistic behavior (Quadrimorphina profunda, Tappanina selmensis, Siphogenerinoides brevispinosa) and/or the ability to calcify in carbonate-corrosive waters (N. truempyi). Nuttallides truempyi, T. selmensis and other buliminids (Bolivinoides cf. decoratus group, Bulimina virginiana) were markedly abundant during the middle Ypresian. Contrary to the long-lived, highly diverse and equitable Velasco fauna, common and abundant taxa reflect highly perturbed assemblages through the earliest Ypresian, with lower diversity and equitability following the PETM extinction. In contrast, the middle Ypresian

Biochar reduces copper toxicity in Chenopodium quinoa Willd. In a sandy soil.

Science.gov (United States)

Buss, Wolfram; Kammann, Claudia; Koyro, Hans-Werner

2012-01-01

Mining, smelting, land applications of sewage sludge, the use of fungicides containing copper (Cu), and other human activities have led to widespread soil enrichment and contamination with Cu and potentially toxic conditions. Biochar (BC) can adsorb several substances, ranging from herbicides to plant-inhibiting allelochemicals. However, the range of potential beneficial effects on early-stage plant growth with regard to heavy metal toxicity is largely unexplored. We investigated the ameliorating properties of a forestry-residue BC under Cu toxicity conditions on early plant growth. Young quinoa plants () were grown in the greenhouse in the presence of 0, 2, and 4% BC application (w/w) added to a sandy soil with 0, 50, or 200 μg g Cu supplied. The plants without BC showed severe stress symptoms and reduced growth shortly after Cu application of 50 μg g and died at 200 μg Cu g. Increasing BC concentrations in the growth medium significantly increased the plant performance without Cu toxicity or under Cu stress. At the 4% BC application rate, the plants with 200 μg g Cu almost reached the same biomass as in the control treatment. In the presence of BC, less Cu entered the plant tissues, which had reduced Cu concentrations in the order roots, shoots, leaves. The amelioration effect also was reflected in the plant-soil system CO gas exchange, which showed clear signs of improvement with BC presence. The most likely ameliorating mechanisms were adsorption of Cu to negatively charged BC surfaces and an improvement of the water supply. Overall, BC seems to be a beneficial amendment with the potential to ameliorate Cu toxicity in sandy soils. Further research with a broad spectrum of different soil types, BCs, and crop plants is required. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Effects of climate and geochemistry on soil organic matter stabilization and greenhouse gas emissions along altitudinal transects in different mountain regions

Science.gov (United States)

Griepentrog, Marco; Bodé, Samuel; Boudin, Mathieu; Dercon, Gerd; Doetterl, Sebastian; Matulanya, Machibya; Msigwa, Anna; Vermeir, Pieter; Boeckx, Pascal

2017-04-01

Terrestrial ecosystems are strongly influenced by climate change and soils are key compartments of the global carbon (C) cycle in terms of their potential to store or release significant amounts of C. This study is part of the interregional IAEA Technical Cooperation Project ``Assessing the Impact of Climate Change and its Effects on Soil and Water Resources in Polar and Mountainous Regions (INT5153)'' aiming to improve the understanding of climate change impacts on soil organic carbon (SOC) in fragile polar and high mountainous ecosystems at local and global scale for their better management and conservation. The project includes 13 benchmark sites situated around the world. Here we present novel data from altitudinal transects of three different mountain regions (Mount Kilimanjaro, Tanzania; Mount Gongga, China; Cordillera Blanca, Peru). All altitudinal transects cover a wide range of natural ecosystems under different climates and soil geochemistry. Bulk soil samples (four field replicates per ecosystem) were subjected to a combination of aggregate and particle-size fractionation followed by organic C, total nitrogen, stable isotope (13C, 15N) and radiocarbon (14C) analyses of all fractions. Bulk soils were further characterized for their geochemistry (Na, K, Ca, Mg, Al, Fe, Mn, Si, P) and incubated for 63 days to assess greenhouse gas emissions (CO2, CH4, NO, N2O). Further, stable C isotopic signature of CO2 was measured to determine the isotopic signature of soil respiration (using Keeling plots) and to estimate potential respiration sources. The following four ecosystems were sampled at an altitudinal transect on the (wet) southern slopes of Mount Kilimanjaro: savannah (920m), lower montane rain forests with angiosperm trees (2020m), upper montane cloud forest with gymnosperm trees (2680m), subalpine heathlands (3660m). Both forests showed highest C contents followed by subalpine and savannah. The largest part of SOC was found in particulate organic matter

Energy policies and the greenhouse effect. V. 1

International Nuclear Information System (INIS)

Grubb, Michael.

1991-01-01

This study represents the culmination of two years of research on the Greenhouse Effect by the Energy and Environmental Programme. It is the fourth study which we have published on the policy aspects of this subject, following Issues for Policymakers, Negotiating Targets, and our report of October 1990 Formulating a Convention. The first volume of the study concentrates on the policy issues arising from attempts to reduce greenhouse gas emissions from the energy sector. The second volume on 'country studies and technical options' provides the detailed analysis on which the conclusions of this book have been based, and will be published in early 1991. Although it was not our intention to produce such a large work at the outset, the upsurge of interest in the subject has expanded the framework of measures being considered to address environmental issues in general and the greenhouse effect in particular. These developments have had a major impact on the size and content. In this book, as in our previous publications, the Programme's work is aimed at moving the policy debate forward as quickly as possible into areas which seem to offer the best prospects for effective policy action. (Author)

[Research methods of carbon sequestration by soil aggregates: a review].

Science.gov (United States)

Chen, Xiao-Xia; Liang, Ai-Zhen; Zhang, Xiao-Ping

2012-07-01

To increase soil organic carbon content is critical for maintaining soil fertility and agricultural sustainable development and for mitigating increased greenhouse gases and the effects of global climate change. Soil aggregates are the main components of soil, and have significant effects on soil physical and chemical properties. The physical protection of soil organic carbon by soil aggregates is the important mechanism of soil carbon sequestration. This paper reviewed the organic carbon sequestration by soil aggregates, and introduced the classic and current methods in studying the mechanisms of carbon sequestration by soil aggregates. The main problems and further research trends in this study field were also discussed.

Identifying Factors Causing Variability in Greenhouse Gas (GHG) Fluxes in a Polygonal Tundra Landscape

Science.gov (United States)

Arora, B.; Wainwright, H. M.; Vaughn, L. S.; Curtis, J. B.; Torn, M. S.; Dafflon, B.; Hubbard, S. S.

2017-12-01

Greenhouse gas (GHG) flux variations in Arctic tundra environments are important to understand because of the vast amount of soil carbon stored in these regions and the potential of these regions to convert from a global carbon sink to a source under warmer conditions. Multiple factors potentially contribute to GHG flux variations observed in these environments, including snowmelt timing, growing season length, active layer thickness, water table variations, and temperature fluctuations. The objectives of this study are to investigate temporal variability in CO2 and CH4 fluxes at Barrow, AK over three successive growing seasons (2012-14) and to determine the factors influencing this variability using a novel entropy-based classification scheme. We analyzed soil, vegetation, and climate parameters as well as GHG fluxes at multiple locations within low-, flat- and high-centered polygons at Barrow, AK as part of the Next Generation Ecosystem Experiment (NGEE) Arctic project. Entropy results indicate that different environmental factors govern variability in GHG fluxes under different spatiotemporal settings. In particular, flat-centered polygons are more likely to become significant sources of CO2 during warm and dry years as opposed to high-centered polygons that contribute considerably to CO2 emissions during cold and wet years. In contrast, the highest CH4 emissions were always associated with low-centered polygons. Temporal variability in CO2 fluxes was primarily associated with factors affecting soil temperature and/or vegetation dynamics during early and late season periods. Temporal variability in CH4 fluxes was primarily associated with changes in vegetation cover and its covariability with primary controls such as seasonal thaw—rather than direct response to changes in soil moisture. Overall, entropy results document which factors became important under different spatiotemporal settings, thus providing clues concerning the manner in which ecosystem

Greenhouse gas emissions from willow-based electricity: a scenario analysis for Portugal and The Netherlands

NARCIS (Netherlands)

Rebelo de Mira, R.; Kroeze, C.

2006-01-01

This study focuses on greenhouse gas emissions from power plants using willow as fuel compared to those using fossil fuels. More specifically, we quantify emissions of nitrous oxide (N2O) from soils on which willow is grown, and compare these to emissions of carbon dioxide (CO2) from fossil

Greenhouse gas flux under warm-season perennial C4 grasses across different soil and climate gradients on the Islands of Hawaii

Science.gov (United States)

Pawlowski, M. N.; Crow, S. E.; Sumiyoshi, Y.; Wells, J.; Kikkawa, H. R.

2011-12-01

Agricultural soils can serve as either a sink or a source for atmospheric carbon (C) and other greenhouse gases (GHG). This is particularly true for tropical soils where influences from climate and soil gradients are wide ranging. Current estimates of GHG flux from soil are often under or overestimated due to high variability in sample sites and inconsistencies in land use and vegetation type, making extrapolation to new study systems difficult. This work aimed to identify patterns of trace fluxes of carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4) across two soil types and three species of warm season perennial C4 grasses: Pennisetum purpureum (Napier grass), Panicum maximum (Guinea grass) and Saccharum officinarum (sugar cane) on the islands of Oahu and Maui in Hawaii. Multiple static vented chambers were installed into replicate plots for each species; flux measurements were made during the growth, fertilization and harvest cycles at set time intervals for one hour and analyzed by gas chromatography. Initial results from Oahu indicate no significant differences in CO2 flux between the P. maximum and P. purpureum species after fertilization or at full growth. We observed an average flux of 143 mg m-2 h-1 and 155 mg m-2 h-1 for P. maximum and P. purpureum respectively at full growth for CO2 and 1.7 μg m-2 h-1and 0.3 μg m-2 h-1 for N2O. Additionally, N2O rates sampled after a typical fertilizer application were significantly greater than at full growth (p=0.0005) with flux rates of 25.2 μg m2h-1 and 30.3 μg m2h-1 for P. maximum and P. purpureum respectively. With a global warming potential of 310 for N2O, even short-term spikes following fertilizer application can cause long lasting effects of GHG emission from agricultural soils. CH4 flux was negligible for all species on the Oahu plots during these sample periods. Globally, water limitation is a major factor influencing the potential productivity of agricultural crops and the sustainability of

Modeling and parametric studies for thermal performance of an earth to air heat exchanger integrated with a greenhouse

International Nuclear Information System (INIS)

Ghosal, M.K.; Tiwari, G.N.

2006-01-01

A thermal model has been developed to investigate the potential of using the stored thermal energy of the ground for greenhouse heating and cooling with the help of an earth to air heat exchanger (EAHE) system integrated with the greenhouse located in the premises of IIT, Delhi, India. Experiments were conducted extensively throughout the year 2003, but the developed model was validated against typical clear and sunny days experiments. Parametric studies performed for the EAHE coupled with the greenhouse illustrate the effects of buried pipe length, pipe diameter, mass flow rate of air, depth of ground and types of soil on the greenhouse air temperatures. The temperatures of the greenhouse air, with the experimental parameters of the EAHE, were found to be, on average 7-8 deg. C higher in the winter and 5-6 deg. C lower in the summer than those of the same greenhouse without the EAHE. The greenhouse air temperatures increase in the winter and decrease in the summer with increasing pipe length, decreasing pipe diameter, decreasing mass flow rate of flowing air inside buried pipe and increasing depth of ground up to 4 m. The predicted and measured values of the greenhouse air temperatures that were verified, in terms of root mean square percent deviation and correlation coefficient, exhibited fair agreement

Climate change: Bio-technologies are facing a huge challenge. Why is climate changing? Control and measurement of greenhouse gases in the atmosphere. Soils at the heart of climate change. Between pollution and climate change, the survival of soil organisms. Modelling microbial degradation in soils to analyse greenhouse gas releases. A threat against plant health. The opinion of the seed industry. Truly living clouds. Language, the other stake of the struggle against climate changes

International Nuclear Information System (INIS)

Salas y Melia, David; Delmotte, Marc; Chenu, Claire; Chevallier, Tiphaine; Mougin, Christian; Lamy, Isabelle; Caquet, Thierry; Garnier, Patricia; Sache, Ivan; Pagesse, Pierre; Amato, Pierre; Desprez, Basile; Vernet, Agnes

2015-01-01

As the Rio Earth Summit in 1992 decided to react to limit the irrecoverable global warming, this publication, through several articles, outlines that this issue has not progressed at all after 23 years on a political point of view, and has even regressed with respect to initially defined objectives, but has progressed in terms of understanding of climate change under the influence of our production modes, notably in the agriculture sector. Thus, the articles discuss or recall the origin and process of climate change, how greenhouse gas emissions are controlled and measured, how soil are impacted or play a role in climate change as the survival of soil organisms is at stake under the pressure of pollution and climate change, how climate change can be a threat for plants, how the seed industry perceives these issues, how micro-organisms present in the air and clouds are now a topic in atmosphere sciences. The last article discusses the importance of intelligibility of scientific publications on these issues

Applied machine learning in greenhouse simulation; new application and analysis

Directory of Open Access Journals (Sweden)

Morteza Taki

2018-06-01

Full Text Available Prediction the inside environment variables in greenhouses is very important because they play a vital role in greenhouse cultivation and energy lost especially in cold and hot regions. The greenhouse environment is an uncertain nonlinear system which classical modeling methods have some problems to solve it. So the main goal of this study is to select the best method between Artificial Neural Network (ANN and Support Vector Machine (SVM to estimate three different variables include inside air, soil and plant temperatures (Ta, Ts, Tp and also energy exchange in a polyethylene greenhouse in Shahreza city, Isfahan province, Iran. The environmental factors which influencing all the inside temperatures such as outside air temperature, wind speed and outside solar radiation were collected as data samples. In this research, 13 different training algorithms were used for ANN models (MLP-RBF. Based on K-fold cross validation and Randomized Complete Block (RCB methodology, the best model was selected. The results showed that the type of training algorithm and kernel function are very important factors in ANN (RBF and MLP and SVM models performance, respectively. Comparing RBF, MLP and SVM models showed that the performance of RBF to predict Ta, Tp and Ts variables is better according to small values of RMSE and MAPE and large value of R2 indices. The range of RMSE and MAPE factors for RBF model to predict Ta, Tp and Ts were between 0.07 and 0.12 °C and 0.28–0.50%, respectively. Generalizability and stability of the RBF model with 5-fold cross validation analysis showed that this method can use with small size of data groups. The performance of best model (RBF to estimate the energy lost and exchange in the greenhouse with heat transfer models showed that this method can estimate the real data in greenhouse and then predict the energy lost and exchange with high accuracy. Keywords: Black box method, Energy lost, Environmental situation, Energy

[Impacts of rice straw biochar on organic carbon and CO2 release in arable soil].

Science.gov (United States)

Ke, Yue-Jin; Hu, Xue-Yu; Yi, Qing; Yu, Zhong

2014-01-01

In order to investigate the stability of biochar and the effect of biochar when added into soil on soil organic carbon, a 130-day incubation experiment was conducted with rice straw biochar produced at 500 degrees C and 700 degrees C (RBC500 and RBC700) and with addition rates of 0% (control), 3%, 6% and 100% (pure biochar), to detect the change of total organic carbon (TOC), easily oxidized carbon (EOC) and status of CO2 release, following addition of biochar in arable soil. Results showed that: the content of both TOC and EOC in soil increased with biochar addition rates comparing with the control. RBC500 had greater contributions to both TOC and EOC increasing amounts than those of RBC700 under the same biochar addition rate. TOC contents of all treatments decreased during the initial 30 days with the largest decreasing amplitude of 15.8%, and tended to be stable in late incubation stages. Same to that of TOC, EOC contents of all treatments also tended to remain stable after 30 days, but in the 30 days of early incubation, EOC in the soil decreased by 72.4% and 81.7% respectively when the added amount of RBC500 was 3% and 6% , while it was reduced by 61.3% and 69.8% respectively when the added amount of RBC700 was 3% and 6%. EOC contents of soil added with biochar produced at the same temperature were similar in the end of incubation. The reduction of soil EOC content in early incubation may be related to mineralization caused by labile fractions of biochar. During the 130-day incubation, the accumulated CO2 releases showed an order of soil and biochar mixtures soil could reduce CO2 release, the largest reduction amplitude is 41.05%. In a long time scale, biochar as a soil amendment is favorable to the deduction of greenhouse gas release and soil carbon immobilization. Biochar could be used as a soil carbon sequestration carrier.

Biochar-mediated reductions in greenhouse gas emissions from soil amended with anaerobic digestates

International Nuclear Information System (INIS)

Martin, Sarah L.; Clarke, Michèle L.; Othman, Mukhrizah; Ramsden, Stephen J.; West, Helen M.

2015-01-01

This investigation examines nitrous oxide (N 2 O) fluxes from soil with simultaneous amendments of anaerobic digestates and biochar. The main source of anthropogenic emissions of N 2 O is agriculture and in particular, manure and slurry application to fields. Anaerobic digestates are increasingly used as a fertiliser and interest is growing in their potential as sources of N 2 O via nitrification and denitrification. Biochar is a stable product of pyrolysis and may affect soil properties such as cation exchange capacity and water holding capacity. Whilst work has been conducted on the effects of biochar amendment on N 2 O emissions in soils fertilised with mineral fertilisers and raw animal manures, little work to date has focused on the effects of biochar on nitrogen transformations within soil amended with anaerobic digestates. The aim of the current investigation was to quantify the effects of biochar application on ammonification, nitrification and N 2 O fluxes within soil amended with three anaerobic digestates derived from different feedstocks. A factorial experiment was undertaken in which a sandy loam soil (Dunnington Heath series) was either left untreated, or amended with three different anaerobic digestates and one of three biochar treatments; 0%, 1% or 3%. Nitrous oxide emissions were greatest from soil amended with anaerobic digestate originating from a maize feedstock. Biochar amendment reduced N 2 O emissions from all treatments, with the greatest effect observed in treatments with maximum emissions. The degree of N 2 O production and efficacy of biochar amelioration of gas emissions is discussed in context of soil microbial biomass and soil available carbon. - Highlights: • Nitrous oxide was emitted from anaerobic digestates applied to soil. • Simultaneous amendment of soil with biochar and anaerobic digestate reduced N 2 O emissions. • Soil nitrate accumulation occurred but was digestate dependent

Comparative effect of ZnO NPs, ZnO bulk and ZnSO4 in the antioxidant defences of two plant species growing in two agricultural soils under greenhouse conditions.

Science.gov (United States)

García-Gómez, Concepción; Obrador, Ana; González, Demetrio; Babín, Mar; Fernández, María Dolores

2017-07-01

The present study has investigated the toxicity of ZnO NPs to bean (Phaseolus vulgaris) and tomato (Solanum lycopersicon) crops grown to maturity under greenhouse conditions using an acidic (soil pH5.4) and a calcareous soil (soil pH8.3). The potentially available Zn in the soils and the Zn accumulation in the leaves from NPs applied to the soil (3, 20 and 225mgZnkg -1 ) and changes in the chlorophylls, carotenoids and oxidative stress biomarkers were measured at 15, 30, 60 and 90days and compared with those caused by bulk ZnO and ZnSO 4 . The available Zn in the soil and the leaf Zn content did not differ among the Zn chemical species, except in the acidic soil at the highest concentration of Zn applied as Zn ions, where the highest values of the two variables were found. The ZnO NPs showed comparable Zn toxicity or biostimulation to their bulk counterparts and Zn salts, irrespective of certain significant differences suggesting a higher activity of the Zn ion. The treatments altered the photosynthetic pigment concentration and induced oxidative stress in plants. ROS formation was observed at Zn plant concentrations ranging from 590 to 760mgkg -1 , but the effects on the rest of the parameters were highly dependent on the plant species, exposure time and especially soil type. In general, the effects were higher in the acidic soil than in the calcareous soil for the bean and the opposite for the tomato. The similar uptakes and toxicities of the different Zn forms suggest that the Zn ions derived from the ZnO NPs exerted a preferential toxicity in plants. However, several results obtained in soils treated with NPs at 3mgZnkg -1 soil indicated that may exist other underlying mechanisms related to the intrinsic nanoparticle properties, especially at low NP concentrations. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of Cassava Processing Effluent on Soil Properties, Growth and ...

African Journals Online (AJOL)

A study, comprising a survey, greenhouse and field experiments was conducted to examine the effect of Cassava Processing Effluent (CPE) on soil chemical properties, maize growth performances and grain yield. In the survey, soil samples were taken (0-15 and 15 – 30cm) of CPE contaminated and non contaminated ...

Inventory and action plan for greenhouse gas emissions and capture in the Lower Saint Lawrence

International Nuclear Information System (INIS)

Granger, F.; Avoine, G.; Michon, P.-Y.; Drainville, L.

2003-01-01

The authors reported on a project designed to provide farmers with concrete information based on data from their enterprise to develop an action plan for the reduction of greenhouse gas emissions. This project involved completing an inventory of greenhouse gas emissions and capture for seven farms located in the Lower Saint Lawrence region of Quebec. The authors presented a balance sheet and action plan for the region under study. A total of six priorities were identified. They encompassed measures such as the optimization of nitrogen management in agricultural soils, to increasing the capture rate of carbon dioxide, and reducing the use of fossil fuels. 6 refs., 6 figs

The greenhouse effect: Its causes, possible impacts, and associated uncertainties

International Nuclear Information System (INIS)

Schneider, S.H.; Rosenberg, N.J.

1991-01-01

The Earth's climate changes. The climatic effects of having polluted the atmosphere with gases such as carbon dioxide (CO2) may already be felt. There is no doubt that the concentration of CO2 in the atmosphere has been rising. CO2 tends to trap heat near the Earth's surface. This is known as the greenhouse effect, and its existence and basic mechanisms are not questioned by atmospheric scientists. What is questioned is the precise amount of warming and the regional pattern of climatic change that can be expected on the Earth from the anthropogenic increase in the atmospheric concentration of CO2 and other greenhouse gases. It is the regional patterns of changes in temperature, precipitation, and soil moisture that will determine what impact the greenhouse effect will have on natural ecosystems, agriculture, and water supplies. These possible effects are discussed in detail. It is concluded, however, that a detailed assessment of the climatic, biological, and societal changes that are evolving and should continue to occur into the next century cannot reliably be made with available scientific capabilities. Nevertheless, enough is known to suggest a range of plausible futures with attendant impacts, both positive and negative, on natural resources and human well being

Early soil knowledge and the birth and development of soil science

NARCIS (Netherlands)

Brevik, E.C.; Hartemink, A.E.

2010-01-01

Soils knowledge dates to the earliest known practice of agriculture about 11,000 BP Civilizations all around the world showed various levels of soil knowledge by the 4th century AD, including irrigation, the use of terraces to control erosion, various ways of improving soil fertility, and ways to

Quantum cascade laser photoacoustic detection of nitrous oxide released from soils for biofuel production

Science.gov (United States)

Couto, F. M.; Sthel, M. S.; Castro, M. P. P.; da Silva, M. G.; Rocha, M. V.; Tavares, J. R.; Veiga, C. F. M.; Vargas, H.

2014-12-01

In order to investigate the generation of greenhouse gases in sugarcane ethanol production chain, a comparative study of N2O emission in artificially fertilized soils and soils free from fertilizers was carried out. Photoacoustic spectroscopy using quantum cascade laser with an emission ranging from 7.71 to 7.88 µm and differential photoacoustic cell were applied to detect nitrous oxide (N2O), an important greenhouse gas emitted from soils cultivated with sugar cane. Owing to calibrate the experimental setup, an initial N2O concentration was diluted with pure nitrogen and detection limit of 50 ppbv was achieved. The proposed methodology was selective and sensitive enough to detect N2O from no fertilized and artificially fertilized soils. The measured N2O concentration ranged from ppmv to ppbv.

Phytoremediation of Soils Contaminated by Chlorinnated Hydrocarbons

Science.gov (United States)

Cho, C.; Sung, K.; Corapcioglu, M.

2001-12-01

In recent years, the possible use of deep rooted plants for phytoremediation of soil contaminants has been offered as a potential alternative for waste management, particularly for in situ remediation of large volumes of contaminated soils. Major objectives of this study are to evaluate the effectiveness of a warm season grass (Eastern Gamagrass) and a cool season prairie grass (Annual Ryegrass) in the phytoremediation of the soil contaminated with volatile organic compounds e.g., trichloroethylene (TCE), tetrachloroethylene (PCE), and 1,1,1-trichloroethane (TCA) and to determine the main mechanisms of target contaminant dissipation. The preliminary tests and laboratory scale tests were conducted to identify the main mechanisms for phytoremediation of the target contaminants, and to apply the technique in green house application under field conditions. The results of microcosm and bioreactor experiments showed that volatilization can be the dominant pathway of the target contaminant mass losses in soils. Toxicity tests, conducted in nutrient solution in the growth room, and in the greenhouse, showed that both Eastern gamagrass and Annual ryegrass could grow without harmful effects at up to 400 ppm each of all three contaminants together. Preliminary greenhouse experimentw were conducted with the 1.5 m long and 0.3 m diameter PVC columns. Soil gas concentrations monitored and microbial biomass in bulk and rhizosphere soil, root properties, and contaminant concentration in soil after 100 days were analyzed. The results showed that the soil gas concentration of contaminants has rapidly decreased especially in the upper soil and the contaminant concentraitons in soil were also significantly decreased to 0.024, 0.228, and 0.002 of C/Co for TCE, PCE and TCA, respectively. Significant plant effects were not found however showed contaminant loss through volatilization and plant contamination by air.

Tracking nitrogen losses in a greenhouse crop rotation experiment in North China using the EU-Rotate{sub N} simulation model

Energy Technology Data Exchange (ETDEWEB)

Guo Ruiying [Ministry of Education Key Laboratory of Arid and Grassland Ecology, School of Life Sciences, Lanzhou University, No. 222 Tianshui Nanlu, Lanzhou 730000, Gansu Province (China); Nendel, Claas, E-mail: nendel@zalf.d [Institute for Landscape Systems Analysis, Leibniz-Center for Agricultural Landscape Research, Eberswalder Strasse 84, 15374 Muencheberg (Germany); Rahn, Clive [Warwick HRI, Wellesbourne CV35 9EF (United Kingdom); Jiang Chunguang; Chen Qing [College of Resources and Environmental Sciences, China Agricultural University, No. 2 Yuanmingyuan Xilu, Haidian, Beijing 100193 (China)

2010-06-15

Vegetable production in China is associated with high inputs of nitrogen, posing a risk of losses to the environment. Organic matter mineralisation is a considerable source of nitrogen (N) which is hard to quantify. In a two-year greenhouse cucumber experiment with different N treatments in North China, non-observed pathways of the N cycle were estimated using the EU-Rotate{sub N} simulation model. EU-Rotate{sub N} was calibrated against crop dry matter and soil moisture data to predict crop N uptake, soil mineral N contents, N mineralisation and N loss. Crop N uptake (Modelling Efficiencies (ME) between 0.80 and 0.92) and soil mineral N contents in different soil layers (ME between 0.24 and 0.74) were satisfactorily simulated by the model for all N treatments except for the traditional N management. The model predicted high N mineralisation rates and N leaching losses, suggesting that previously published estimates of N leaching for these production systems strongly underestimated the mineralisation of N from organic matter. - The EU-Rotate{sub N} model can satisfactorily simulate crop N uptake and N{sub min} dynamics in a typical greenhouse cucumber production system of North China

Control of Pathogenicity Root-Knot Nematode (Meloidogyne Javanica by Earthworm Eisenia Feoetida-Based Products in Greenhouse

Directory of Open Access Journals (Sweden)

M. Rostami

2016-06-01

Full Text Available Introduction: Biocontrol of nematode agents in order to decrease the hazardous impacts of chemical pesticide application including problems of public health and environmental pollution is apriority. In this study, solid (Vermicompost and liquid products (Liquid Vermicompost, Vermiwash and Coelomic fluidof the earthworm species Eisenia fetida were tested against root-knot nematode, Meloidogyne javanica in greenhouse conditions. Materials and Methods: In this study, Solid (Vermicompost and Liquid products(Wormtea, Vermiwash, Coelomic fluid erthworms (Eisenia foetida were tested against Meloidogyne javanica and also the effect of Vermicompost was evaluated on Pathogenicity of various nematode initial inoculum in two stage greenhouse conditions. Earthworm-based products (Vermicompost, Wormtea, Vermiwash and Coelomic fluid were added to tomato pots. Various treatments of liquid as well as solid products and their combination were used in the greenhouse trial. The first Stage greenhouse experiment- Tomato seeds grown in 2 kg sterilized soil. In the treatments having Vermicompost, pots incorporated with 200 gr of this compost homogeneously mixed with soil. After plants reached at two leaf stage, to study the effects of liquid products (Wormtea, Vermiwash, and Coelomic fluid they added to the pots (500cc along with the irrigation water every week and after of 4 leaf stage, 5000 nematode eggs and larva inoculated to the tomato host plants. 90 days after nematode inoculation, plant and nematode growth indices separately measured and compared. The experiment conducted based on completely randomized design having four replicates. The second stage greenhouse experiment- Tomato seeds grown in 2 kg sterilized soil. In the treatments, pots incorporated with 200 gr of this compost homogeneously mixed with soil. After of 4 leaf stage, 0,1000,2000,4000 and 10000 nematode eggs and larva inoculated to the tomato host plants. 90 days after nematode inoculation, plant

Influence of soil organic C content on the greenhouse gas emission potential after application of biogas residues or cattle slurry - Results from a pot experiment

Science.gov (United States)

Heintze, Gawan

2017-04-01

Influence of soil organic C content on the greenhouse gas emission potential after application of biogas residues or cattle slurry - Results from a pot experiment Gawan Heintze1,2, Tim Eickenscheidt1, Urs Schmidthalter2 and Matthias Drösler1 1University of Applied Sciences Weihenstephan-Triesdorf, Chair of Vegetation Ecology, Weihenstephaner Berg 4, 85354 Freising, Germany 2Technische Universität München, Chair of Plant Nutrition, Emil-Ramann-Str. 2, 85354 Freising, Germany The European Union Renewable Energy Directive, which sets a binding target of a final energy consumption of 20% from renewable sources by 2020, has markedly promoted the increase of biogas plants, particularly in Germany. As a consequence, a large amount of biogas residue remains as a by-product of the fermentative process. These residues are now widely used instead of mineral fertilizers or animal slurries to maintain soil fertility and productivity. However, to date, the effect of the application of biogas residue on greenhouse gas (GHG) emission, compared to that of other organic fertilizers, is contradictory in literature, not having been completely understood. It is often stated that GHG fluxes are closely related to the quality of the raw material, particularly the type of soil to which the digestates are applied. This study addresses the questions (a) to what extent are the applications of biogas digestate and cattle slurry different in terms of their GHG emission (CO2, CH4 and N2O) potential, and (b) how do different soil organic carbon contents (SOCs) influence the rate of GHG exchange. We hypothesize that, i) cattle slurry application enhances the CO2 and N2O fluxes compared to the biogas digestate due to the overall higher C and N input, and ii) that with increasing SOC and N content, higher emissions of CO2 and N2O can be expected. The study was conducted as a pot experiment. Biogas digestate and cattle slurry were applied to and incorporated into three different soil types with

Cultivos de cobertura: efectos sobre la macroporosidad y la estabilidad estructural de un suelo franco-limoso Cover crops: effects on soil macroporosity and soil structural stability in a silt loam soil

Directory of Open Access Journals (Sweden)

María Florencia Varela

2011-07-01

Full Text Available Los suelos franco-limosos manejados con siembra directa a menudo poseen porosidad estructural baja e inestable. Con el objetivo de determinar la capacidad de los cultivos de cobertura (CC de mejorar la porosidad y estabilidad estructural de estos suelos se llevaron a cabo experimentos de campo y de invernáculo. Ambos tuvieron tratamientos con y sin CC (avena, Avena sativa L., en rotación con soja (Glicine max L. Merr.. Luego de los CC se midieron densidad aparente (DA, el índice de inestabilidad estructural (IE y en el ensayo de invernáculo además, se midió la evolución de la distribución de tamaño de poros (DTP. En ambos ensayos la introducción de CC no disminuyó la DA, aunque incrementó la estabilidad del suelo (PNo- till (NT silt loam topsoils have often a low and unstable structural porosity. The objective of this study was to determine the capability of cover crops (CC of improving the structural porosity and stability of silt loam soils under NT. Greenhouse and field experiments were carried out on a silt loam soil (Typic Argiudoll with and without CC (oat, Avena sativa L. in crop sequences with soybean (Glicine max L. Merr.. Soil bulk density (DA and aggregate instability index (IE were measured after the CC in both experiments. In the greenhouse experiment, soil pore size distribution (DTP was measured. The use of CC did not change DA, but soil IE was significantly lower in crop sequences with CC (P < 0.05 both under field and greenhouse conditions. Stability increases were likely due to the effect of CC residues and root mass. No differences in DTP were found between treatments, although a significant effect of sampling date was observed (P<0.05. Changes in DTP were due to significant increases in mesopore (517.5% and macropore (52.7% volumes. Such changes occurred in all the treatments, probably due to the soil wetting-drying cycles. The results found in this study agree with other studies carried out on silt loams in the

The use of 32P to study root growth of soybean as affected by soil compaction

International Nuclear Information System (INIS)

Sisworo, Elsje L.; Sisworo, Widjang H.; Syaukat, Sri Harti; Wemay, Johannis; Haryanto

1996-01-01

Two greenhouse and two field experiments have been conducted to study the effect of soil compaction on root and plant growth of soybean, by using 32 P in the form of carrier free KH 2 32 PO 4 solution. In the greenhouse experiment it was clearly shown that by increasing soil compaction the growth of roots and shoots was increasingly inhibited. The growth of roots was expressed in √% arcsin converted from 32 P activity (counts per minute, cpm) in the shoots and 32 P activity in the shoots (cpm) without convertion. Plant growth was expressed in plant height, number of leaves, dry weight of pods and shoots. In the field experiment, it was shown distinctively that root growth in the 15 cm soil depth was inhibited whith the increase of soil compaction. Similar with the greenhouse experiments the of plants of roots was expressed in cpm 32 P of roots, shoots, and pods, while, the growth of plants was expressed in plant height, number of pods, and dry weight of pods, seeds, and stover. (author). 19 refs, 4 tabs, 6 figs

Greening the greenhouse grower

DEFF Research Database (Denmark)

Staats, Henk; Jansen, Lilian; Thøgersen, John

2011-01-01

Growing plants and flowers in greenhouses is a commercial activity that imposes a burden on the environment. Recently a system of registration, control, and licensing has been developed by the sector of greenhouse growers in the Netherlands, acknowledged by the state. The current study was executed...... to understand the achievements of the greenhouse growers within this system. We applied a social-cognitive model to understand intentions to reduce emissions and predict actual pesticide use. The social-cognitive concepts from the model were measured in a questionnaire that was completed by 743 greenhouse...

The Dynamic Greenhouse Challenge

Science.gov (United States)

Roman, Harry T.

2010-01-01

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

The role of clouds and oceans in global greenhouse warming. Final report

Energy Technology Data Exchange (ETDEWEB)

Hoffert, M.I.

1996-10-01

This research focuses on assessing connections between anthropogenic greenhouse gas emissions and global climatic change. it has been supported since the early 1990s in part by the DOE ``Quantitative Links`` Program (QLP). A three-year effort was originally proposed to the QLP to investigate effects f global cloudiness on global climate and its implications for cloud feedback; and to continue the development and application of climate/ocean models, with emphasis on coupled effects of greenhouse warming and feedbacks by clouds and oceans. It is well-known that cloud and ocean processes are major sources of uncertainty in the ability to predict climatic change from humankind`s greenhouse gas and aerosol emissions. And it has always been the objective to develop timely and useful analytical tools for addressing real world policy issues stemming from anthropogenic climate change.

The Contribution of Soils to North America's Current and Future Climate

Science.gov (United States)

Mayes, M. A.; Reed, S.; Thornton, P. E.; Lajtha, K.; Bailey, V. L.; Shrestha, G.; Jastrow, J. D.; Torn, M. S.

2015-12-01

This presentation will cover key aspects of the terrestrial soil carbon cycle in North America and the US for the upcoming State of the Carbon Cycle Report (SOCCRII). SOCCRII seeks to summarize how natural processes and human interactions affect the global carbon cycle, how socio-economic trends affect greenhouse gas concentrations in the atmosphere, and how ecosystems are influenced by and respond to greenhouse gas emissions, management decisions, and concomitant climate effects. Here, we will summarize the contemporary understanding of carbon stocks, fluxes, and drivers in the soil ecosystem compartment. We will highlight recent advances in modeling the magnitude of soil carbon stocks and fluxes, as well as the importance of remaining uncertainties in predicting soil carbon cycling and its relationship with climate. Attention will be given to the role of uncertainties in predicting future fluxes from soils, and how those uncertainties vary by region and ecosystem. We will also address how climate feedbacks and management decisions can enhance or minimize future climatic effects based on current understanding and observations, and will highlight select research needs to improve our understanding of the balance of carbon in soils in North America.

Greenhouse cooling and heat recovery using fine wire heat exchangers in a closed pot plant greenhouse: design of an energy producing greenhouse

NARCIS (Netherlands)

Bakker, J.C.; Zwart, de H.F.; Campen, J.B.

2006-01-01

A greenhouse cooling system with heat storage for completely closed greenhouses has been designed, based on the use of a fine wire heat exchanger. The performance of the fine wire heat exchangers was tested under laboratory conditions and in a small greenhouse compartment. The effects of the system

ARBUSCULAR MYCORRHIZAL FUNGI INCREASED EARLY GROWTH OF GAHARU WOOD OF Aquilaria malaccencsis and A. crasna UNDER GREENHOUSE CONDITIONS

Directory of Open Access Journals (Sweden)

Maman Turjaman

2006-07-01

Full Text Available Gaharu wood stand has an important source of profits to the forest community in South and Southeast Asia tropical forest countries, but Aquilaria species have reduced in number and turn out to be endangered due to overexploitation.   Today,   the planting stocks of   Aquilaria species are not sufficient to sustain the yield of gaharu wood and promote forest conservation.  The objective of this study was to determine   the effect of   five arbuscular mycorrhizal (AM fungi: Entrophospora sp., Gigaspora decipiens, Glomus clarum, Glomus sp. ZEA, and Glomus sp. ACA, on the early growth of  Aquilaria malaccensis and A. crasna under greenhouse conditions. The seedlings of  Aquilaria spp. were inoculated with Entrophospora sp., Gi. decipiens, Glomus clarum, Glomus sp. ZEA, Glomus sp. ACA and uninoculated (control under greenhouse conditions. Then, percentage AM colonization, plant growth, survival rate and nitrogen (N and phosphorus (P content and mycorrhizal dependence (MD were measured. The percentage AM colonization of A. malaccensis and A. crasna ranged from 83 to 97% and from 63 to 78%, respectively. Colonization by five AM fungi increased plant height, diameter, and shoot and root dry weights. N and P content of  the seedlings were also increased by AM colonization. Survival rates were higher in the AM-colonized seedlings at 180 days after transplantation than those in the control seedlings. The MD of Aquilaria species was higher than 55 %. The results suggested that AM fungi can be inoculated`to Aquilaria species under nursery conditions to obtain vigorous seedlings, and the field experiment is underway to clarify the role of AM fungi under field conditions.

Regional greenhouse climate effects

International Nuclear Information System (INIS)

Hansen, J.; Rind, D.; Delgenio, A.; Lacis, A.; Lebedeff, S.; Prather, M.; Ruedy, R.; Karl, T.

1990-01-01

The authors discuss the impact of an increasing greenhouse effect on three aspects of regional climate: droughts, storms and temperature. A continuous of current growth rates of greenhouse gases causes an increase in the frequency and severity of droughts in their climate model simulations, with the greatest impacts in broad regions of the subtropics and middle latitudes. But the greenhouse effect enhances both ends of the hydrologic cycle in the model, that is, there is an increased frequency of extreme wet situations, as well as increased drought. Model results are shown to imply that increased greenhouse warming will lead to more intense thunderstorms, that is, deeper thunderstorms with greater rainfall. Emanual has shown that the model results also imply that the greenhouse warming leads to more destructive tropical cyclones. The authors present updated records of observed temperatures and show that the observations and model results, averaged over the globe and over the US, are generally consistent. The impacts of simulated climate changes on droughts, storms and temperature provide no evidence that there will be regional winners if greenhouse gases continue to increase rapidly

Assessment of the role of plants in the bioremediation of two hydrocarbon-contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Bailey, V L; McGill, W G [Alberta Univ., Edmonton, AB (Canada). Dept. of Renewable Resources

1999-01-01

Phytoremediation has been considered as a viable alternative for cleaning up contaminated soils. A study was conducted to examine the potential for plant-assisted bioremediation of hydrocarbon contaminated soils using wheat, canola, sunflower, fababean, and alsike clover. Crops were grown to maturity in greenhouses. Creosote and oil contaminated soils were used. The soils and plant tissues were then extracted and measured for dichloromethane-extractable organic (DEO) materials. The concentrations of DEO within the soil was them compared with non-planted samples. The study showed that at the end of a three month period there was no major difference in DEO concentrations in any of the soils. After six months, the DEO concentrations of the greenhouse soils had decreased compared to the reserved samples, but there was no major change in concentration due to the presence of any of the plant species. The results indicate that the role of plants in bioremediation systems, both as enhancers of bioremediation systems and as the possible sinks of contaminant C, should be further studied. 22 refs., 1 tab., 7 figs.

Assessment of the role of plants in the bioremediation of two hydrocarbon-contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Bailey, V.L.; McGill, W.G. [Alberta Univ., Edmonton, AB (Canada). Dept. of Renewable Resources

1999-07-01

Phytoremediation has been considered as a viable alternative for cleaning up contaminated soils. A study was conducted to examine the potential for plant-assisted bioremediation of hydrocarbon contaminated soils using wheat, canola, sunflower, fababean, and alsike clover. Crops were grown to maturity in greenhouses. Creosote and oil contaminated soils were used. The soils and plant tissues were then extracted and measured for dichloromethane-extractable organic (DEO) materials. The concentrations of DEO within the soil was them compared with non-planted samples. The study showed that at the end of a three month period there was no major difference in DEO concentrations in any of the soils. After six months, the DEO concentrations of the greenhouse soils had decreased compared to the reserved samples, but there was no major change in concentration due to the presence of any of the plant species. The results indicate that the role of plants in bioremediation systems, both as enhancers of bioremediation systems and as the possible sinks of contaminant C, should be further studied. 22 refs., 1 tab., 7 figs.

Assessment of the role of plants in the bioremediation of two hydrocarbon-contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Bailey, V.L.; McGill, W.G. [Alberta Univ., Edmonton, AB (Canada). Dept. of Renewable Resources

1999-09-01

Phytoremediation has been considered as a viable alternative for cleaning up contaminated soils. A study was conducted to examine the potential for plant-assisted bioremediation of hydrocarbon contaminated soils using wheat, canola, sunflower, fababean, and alsike clover. Crops were grown to maturity in greenhouses. Creosote and oil contaminated soils were used. The soils and plant tissues were then extracted and measured for dichloromethane-extractable organic (DEO) materials. The concentrations of DEO within the soil was them compared with non-planted samples. The study showed that at the end of a three month period there was no major difference in DEO concentrations in any of the soils. After six months, the DEO concentrations of the greenhouse soils had decreased compared to the reserved samples, but there was no major change in concentration due to the presence of any of the plant species. The results indicate that the role of plants in bioremediation systems, both as enhancers of bioremediation systems and as the possible sinks of contaminant C, should be further studied. 22 refs., 1 tab., 7 figs.

Assessment of the role of plants in the bioremediation of two hydrocarbon-contaminated soils

International Nuclear Information System (INIS)

Bailey, V.L.; McGill, W.G.

1999-01-01

Phytoremediation has been considered as a viable alternative for cleaning up contaminated soils. A study was conducted to examine the potential for plant-assisted bioremediation of hydrocarbon contaminated soils using wheat, canola, sunflower, fababean, and alsike clover. Crops were grown to maturity in greenhouses. Creosote and oil contaminated soils were used. The soils and plant tissues were then extracted and measured for dichloromethane-extractable organic (DEO) materials. The concentrations of DEO within the soil was them compared with non-planted samples. The study showed that at the end of a three month period there was no major difference in DEO concentrations in any of the soils. After six months, the DEO concentrations of the greenhouse soils had decreased compared to the reserved samples, but there was no major change in concentration due to the presence of any of the plant species. The results indicate that the role of plants in bioremediation systems, both as enhancers of bioremediation systems and as the possible sinks of contaminant C, should be further studied. 22 refs., 1 tab., 7 figs

National Greenhouse Gas Emission Inventory

Data.gov (United States)

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

The greenhouse effect

International Nuclear Information System (INIS)

Berger, A.

1991-01-01

The greenhouse effect on earth can be defined as the long wave energy trapped in the atmosphere. Climate forcing and climate system response within which climate feedback mechanisms are contained are determined. Quantitative examples illustrate what could happen if the greenhouse effect is perturbed by human activities, in particular if CO2 atmospheric concentration would double in the future. Recent satellite measurements of the greenhouse effect are given. The net cooling effect of clouds and whether or not there will be less cooling by clouds as the planet warms are also discussed

Program to monitor and evaluate a passive solar greenhouse/aquaculture system. Final report

Energy Technology Data Exchange (ETDEWEB)

1982-01-01

A temperature monitoring program of Amity's solar greenhouse demonstrated that air, soil, and water temperatures can be maintained at optimal levels without supplemental heat. A foil reflector placed in front of the greenhouse glazing at an angle of between 0 and 5/sup 0/ above horizontal enhanced direct light entering the greenhouse by as much as 22%. Aquaculture in the water heat storage of a solar greenhouse has been a success. Fish reached harvest size in about seven months. The two species that were received the best by the public were African perch (Tilapia mossambica) and channel catfish (Ictalurus punctatus). Although carp (Cyprinus carpio) were the fastest growers they were not well received by the public. Linking hydroponics to greenhouse aquaculture shows a lot of promise. Different support medias were examined and tomatoes and European cucumbers were raised successfully. A savonius windmill was successfully linked to an aquaculture aeration system but because of the wind pattern in the Willamette valley the windmill system did not provide air in the evening when it was needed most. Alternate designs are discussed. Locally grown fish diets were evaluated for their ability to promote fish growth. Diets such as water hyacinth, duckweed, earthworms, beans, and comfrey were raised on the Amity site, pelleted with a hand grinder and solar dried. Duckweed and earthworms appear to hold promise for a nutritous, easy to grow and pelletize, food source. Amity's solar greenhouse, three coldframe designs and a PVC tunnel cloche were compared in a vegetable growing trial. Most impressive was the cloche design because it provided adequate protection, was inexpensive and very easy to build.

Monitoring soil carbon will prepare growers for a carbon trading system

Directory of Open Access Journals (Sweden)

Emma C. Suddick

2013-07-01

Full Text Available California growers could reap financial benefits from the low-carbon economy and cap-and-trade system envisioned by the state's AB 32 law, which seeks to lower greenhouse gas emissions statewide. Growers could gain carbon credits by reducing greenhouse gas emissions and sequestering carbon through reduced tillage and increased biomass residue incorporation. First, however, baseline stocks of soil carbon need to be assessed for various cropping systems and management practices. We designed and set up a pilot soil carbon and land-use monitoring network at several perennial cropping systems in Northern California. We compared soil carbon content in two vineyards and two orchards (walnut and almond, looking at conventional and conservation management practices, as well as in native grassland and oak woodland. We then calculated baseline estimates of the total carbon in almond, wine grape and walnut acreages statewide. The organic walnut orchard had the highest total soil carbon, and no-till vineyards had 27% more carbon in the surface soil than tilled vineyards. We estimated wine grape vineyards are storing significantly more soil carbon per acre than almond and walnut orchards. The data can be used to provide accurate information about soil carbon stocks in perennial cropping systems for a future carbon trading system.

The effective mitigation of greenhouse gas emissions from rice paddies without compromising yield by early-season drainage.

Science.gov (United States)

Islam, Syed Faiz-Ul; van Groenigen, Jan Willem; Jensen, Lars Stoumann; Sander, Bjoern Ole; de Neergaard, Andreas

2018-01-15

Global rice production systems face two opposing challenges: the need to increase production to accommodate the world's growing population while simultaneously reducing greenhouse gas (GHG) emissions. Adaptations to drainage regimes are one of the most promising options for methane mitigation in rice production. Whereas several studies have focused on mid-season drainage (MD) to mitigate GHG emissions, early-season drainage (ED) varying in timing and duration has not been extensively studied. However, such ED periods could potentially be very effective since initial available C levels (and thereby the potential for methanogenesis) can be very high in paddy systems with rice straw incorporation. This study tested the effectiveness of seven drainage regimes varying in their timing and duration (combinations of ED and MD) to mitigate CH 4 and N 2 O emissions in a 101-day growth chamber experiment. Emissions were considerably reduced by early-season drainage compared to both conventional continuous flooding (CF) and the MD drainage regime. The results suggest that ED+MD drainage may have the potential to reduce CH 4 emissions and yield-scaled GWP by 85-90% compared to CF and by 75-77% compared to MD only. A combination of (short or long) ED drainage and one MD drainage episode was found to be the most effective in mitigating CH 4 emissions without negatively affecting yield. In particular, compared with CF, the long early-season drainage treatments LE+SM and LE+LM significantly (pemissions were small and not significantly affected by ED. It is concluded that ED+MD drainage might be an effective low-tech option for small-scale farmers to reduce GHG emissions and save water while maintaining yield. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

The effects of fire on greenhouse gas fluxes from mosses and lichen patches in the Yukon Kuskokwim Delta, AK.

Science.gov (United States)

Navarro-Perez, E.; Natali, S.; Schade, J. D.; Holmes, R. M.; Mann, P. J.

2017-12-01

Climate change has altered patterns of temperature, emissions of greenhouse gases and increased fire frequencies, especially in the Artic. Until recently, the Arctic has been a carbon (C) sink, but have begun releasing C in recent years, likely in response to warming temperatures, permafrost thaw and resulting changes in microbial processes. In addition, increases in fire frequency and intensity are changing vegetation patterns, particularly the relative importance of mosses and lichens. These changes alter soil temperatures, nutrient availability, and moisture, consequently affecting microbial processes and the release of greenhouse gases (GHG) such as N2O, CO2 and CH4. The objective of this research was to understand how recent fires in the Yukon-Kuskokwim River Delta in southwest Alaska are affecting the emission of GHGs from peat plateau soils. We hypothesized that the presence of mosses and lichen would change soil moisture and temperature, leading to changes in GHG production after fire. We also hypothesized that fire would increase soil nutrient availability, which would increase microbial process rates and GHG emissions. To test these hypotheses, we measured N2O, CH4 and CO2 fluxes from moss and lichen patches in three burned and unburned areas and collected soil cores for analyses of gravimetric soil moisture, carbon and nitrogen concentrations, and N mineralization rates. Soil temperatures were measured in the field with a thermocouple. Results demonstrated low but measurable CH4 emissions from all patches, suggesting peat plateaus in the YK Delta may be CH4 sources. In addition, CO2 emissions were higher in soils under lichen patches in burned areas than unburned controls. Finally, results suggest that burned areas have higher concentrations of extractable NH4 and NO3, and that increased N may be increasing soil respiration.

The soil and air quality connection: abstracts of the 36. Alberta soil science workshop

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-07-01

The workshop has the following general categories of papers (with abstracts only): plenary session, volunteer session I; volunteer session II; technical session I - soil reclamation, and soil fertility; technical session II - soil conservation, and soil information; and poster presentations. Twelve individual papers are abstracted/indexed as follows: (1) greenhouse gas emissions from Canadian prairie agriculture; (2) acid deposition, critical loads, soil sensitivity, and environmental responses; (3) the downwind health risks of intensive livestock production; (4) nitrous oxide emission as affected by tillage practices and fertilizer association; (5) a conceptual system for assigning sensitivities to potentially acidifying inputs to soils in the oil sands regions of Alberta; (6) a particle tracer method for soil aggregation and translocation studies; (7) DNA adduct quantification in Eisenia fetida after subchronic exposures to creosote contaminated soils; (8) the physical distribution of anthropogenic mercury in nine contaminated soils; (9) bioremediation of hydrocarbon-contaminated soils: are treatability and ecotoxicity endpoints related?; (10) land reclamation using oil sand processing tailings: a field study; (11) assessment of toxicity based criteria for disposal of drilling waste in oil and gas exploration; and (12) toxicity assessment of approved drilling mud additives in the oil and gas sector.

Evaluation of HYDRUS-1D for Estimating Evapotranspiration of Bell Pepper Regulated by Cloud-based Fertigation System in Greenhouse

Science.gov (United States)

Ito, Y.; Honda, R.; Takesako, H.; Ozawa, K.; Kita, E.; Kanno, M.; Noborio, K.

2017-12-01

A fertile surface layer, contaminated with radiocesium resulting from the accident of the Fukushima Daiichi Nuclear Power Plant in 2011, was removed and replaced by non-fertile soil in Fukushima farmlands. In a greenhouse, we used a commercially-available cloud-based fertigation system (CBFS) for regulating an application rate of liquid fertilizer to bell pepper grown in the non-fertile soil. Although the CBFS regulates the application rate based on a weekly trend of volumetric water content (Θw) remotely measured at the soil surface using a soil moisture sensor if all applied water being consumed by plants in a greenhouse is not known. Evapotranspiration of green pepper grown with the CBFS was estimated by HYDRUS-1D. Experiments in a greenhouse were conducted in Fukushima, Japan, from September 1st to October 31st in 2016. Bell pepper plants were transplanted in the begging of June in 2016. The Penman-Monteith equation was used to estimate evapotranspiration, representing transpiration since the soil surface was covered with plastic mulch. Time domain reflectometry (TDR) probes were horizontally installed to monitor changes in Θw at 5, 10, 20, and 30 cm deep from the soil surface. The van Genuchten-Mualem hydraulic model for water and heat flow in soil was used for HYDRUS-1D. A precipitation rate for the upper boundary condition was given as an irrigation rate. We assumed wind speed was always 0.6 m s-1 for the Penman-Monteith equation. The amount of evapotranspiration estimated with the Penman-Monteith equation agreed well with the amount of irrigated water measured. The evapotranspiration simulated with HYDRUS-1D agreed well with that estimated with the Penman-Monteith equation. However, Θw at all depth were underestimated with Hydrus-1D by approximately 0.05 m3 m-3 and differences of Θw between measured and estimated with HYDRYS-1D became larger at deeper the soil depths. This might be attributed to larger water flow occurred because of a free drainage used

Use of Carbon Isotopic Tracers in Investigating Soil Carbon Sequestration and Stabilization in Agroecosystems

International Nuclear Information System (INIS)

2017-09-01

The global surface temperatures have been reported to increase at an average rate of 0.06 C (0.11 F) per decade. This observed climate change known as the greenhouse effect is attributed to the emission of greenhouse gases (GHGs), including carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) to the atmosphere, resulting in trapping the heat near the earth’s surface causing global warming. World soils are the largest reservoir of terrestrial carbon and that soils are a source or sink of GHGs depending on land use management. Recognizing the urgent need to address the soil organic matter constraints for a sustainable agricultural production to ensure food security, this publication provides an integrated view on conventional and isotopic methods of measuring and modelling soil carbon dynamics, and the use nuclear and radioisotope tracer techniques in in-situ glasshouse and field labelling techniques to assess soil organic matter turnover and sequestration.

Greenhouse gas emissions from liquid dairy manure: Prediction and mitigation

DEFF Research Database (Denmark)

Petersen, Søren O.

2017-01-01

The handling and use of manure on livestock farms contributes to emissions of the greenhouse gases (GHG) CH4 and N2O, especially with liquid manure management. Dairy farms are diverse with respect to manure management, with practices ranging from daily spreading to long-term storage for more......, and use of treatment technologies. Also, effects of treatment and handling on the properties of field-applied manure must be taken into account. Storage conditions and manure composition importantly define carbon and nitrogen transformations, and the resulting emissions of CH4 and N2O, as well as CO2...... application, manure and soil together define the equilibrium distribution of labile carbon and nitrogen between bulk soil and manure hotspots. This introduces heterogeneity with respect to potential for N2O emissions, which is not represented in existing prediction models. Manure treatment and management...

Soil Carbon 4 per mille

Science.gov (United States)

Minasny, Budiman; van Wesemael, Bas

2017-04-01

The '4 per mille Soils for Food Security and Climate' was launched at the COP21 aiming to increase global soil organic matter stocks by 4 per mille (or 0.4 %) per year as a compensation for the global emissions of greenhouse gases by anthropogenic sources. This paper surveyed the soil organic carbon (SOC) stock estimates and sequestration potentials from 20 regions in the world (New Zealand, Chile, South Africa, Australia, Tanzania, Indonesia, Kenya, Nigeria, India, China Taiwan, South Korea, China Mainland, United States of America, France, Canada, Belgium, England & Wales, Ireland, Scotland, and Russia) and asked whether the 4 per mille initiative is feasible. This study highlights region specific efforts and scopes for soil carbon sequestration. Reported soil C sequestration rates generally show that under best management practices, 4 per mille or even higher sequestration rates can be accomplished. High C sequestration rates (up to 10 per mille) can be achieved for soils with low initial SOC stock (topsoil less than 30 t C ha-1), and at the first twenty years after implementation of best management practices. In addition, areas that have reached equilibrium but not at their saturation level will not be able to further increase their sequestration. We found that most studies on SOC sequestration globally only consider topsoil (up to 0.3 m depth), as it is considered to be most affected by management techniques. The 4 per mille initiative was based on a blanket calculation of the whole global soil profile C stock, however the potential to increase SOC is mostly on managed agricultural lands. If we consider 4 per mille on global topsoil of agricultural land, SOC sequestration is about 3.6 Gt C per year, which effectively offset 40% of global anthropogenic greenhouse gas emissions. As a strategy for climate change mitigation, soil carbon sequestration buys time over the next ten to twenty years while other effective sequestration and low carbon technologies become