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Status and evaluation of the selected soil nutrients irrigated by unconventional water (Case study: Qom)
2016
Arast, Mina | Zehtabian, Gholamreza | Jafari, Mohammad | Khosravi, Hassan | Jabalbarezi, Bahareh
Population’s exponential growth along with drought has increased water resources limitation, especially in arid and semi-arid area. Therefore, the use of non-conventional water is an important tool for water resource management. If unconventional water has no negative impact on soil properties and water, it can be used for irrigation coupled with desertification projects. So, this paper tries to present the effect of irrigation with municipal wastewater, salt water, brackish water, and combination of salty water and wastewater on some soil properties including nitrogen, phosphorus, and potassium in Qom plain. Soil samples were taken from agricultural land treated by wastewater, saline water, brackish water, combination of salty water, and wastewater and range land as control in five treatments from depths of 0-30 and 60-90 centimeter. The results showed that wastewater has increased the amount of N, P, and K to other treatments and control area. The concentration of potassium in surface layer of area treated by combination of salty water and wastewater with amount of 459.39 ppm has the most significant difference to control and other treatments. Also, the maximum amount of nitrogen was observed in sub layer of saline and brackish water treatment with amount of 0.08 percent.
显示更多 [+] 显示较少 [-]Effect of a thermal power plant waste fly ash on leguminous and non-leguminous leafy vegetables in extracting maximum benefits from P and K fertilization
2015
Inam, Akhtar | Sahay, Seema
Although the Indian population is largely vegetarian, not much attention has been given to the cultivation of vegetables, as compared to other crops like cereals, pulses and oil seeds. Therefore, the present study was conducted on two leafy vegetables, spinach (Spanacia oleracea L.) and methi (Trigonella foenum graecum L.) commonly grown in Aligarh, as the two popular vegetables of Indian diet. The study was conducted for two successive years and during the first year, phosphorus and fly ash interactions with a uniform dose of nitrogen and potassium on both vegetables was observed. During the second year, while keeping nitrogen and phosphorus uniform, potassium and fly ash combinations were studied again with both vegetables, to determine the optimum dose of inorganic fertilizers and fly ash combination. It was observed that fly ash applied at the rate of 15 t ha-1 along with N40P15K20, proved optimum for spinach while in the case of methi, N20P30K40 + FA10 was sufficient. Therefore, both vegetables can safely be grown with 10 to 15 t ha-1 of fly ash and a comparatively lower quantity of NPK.
显示更多 [+] 显示较少 [-]Factors influencing nitrogen retention in forest soils.
1991
Duckworth C.M.S. | Cresser M.S.
Changes in pigment concentration and composition in Norway spruce induced by long-term exposure to low levels of ozone.
1995
Mikkelsen T.N. | Dodell B. | Lutz C.
Charges critiques pour la vegetation.
1993
Thimonier A. | Dupouey J.L.
Effects of ammonia on periphytic communities.
1990
Niederlehner B.R. | Cairns J. Jr.
Critical loads for nitrogen deposition on forest ecosystems.
1989
Schulze E.D. | Vries W. de | Hauhs M. | Rosen K. | Rasmussen L. | Tamm C.O. | Nilsson J.
Challenges in quantifying biosphere-atmosphere exchange of nitrogen species
2007
Sutton, M.A. | Nemitz, E. | Erisman, J.W | Beier, C. | Butterbach Bahl, K. | Cellier, Pierre | de Vries, W. | Cotrufo, F. | Skiba, U | Di Marco, C. | Jones, S. | Laville, Patricia | Soussana, Jean-François | Loubet, Benjamin | Twigg, M. | Famulari, D. | Whitehead, J. | Gallagher, M.W. | Neftel, A. | Flechard, C.R. | Herrmann, B. | Calanca, P.L. | Schjoerring, J.K. | Daemmgen, U. | Horvath, L. | Tang, Y.P. | Emmett, B.A. | Tietema, A. | Penuelas, J. | Kesik, M. | Brueggemann, N. | Pilegaard, K. | Vesala, T. | Campbell, C.L. | Olesen, J.E. | Dragosits, U. | Theobald, M.R. | Levy, P. | Mobbs, D.C. | Milne, R. | Viovy, N. | Vuichard, N. | Smith, J.U. | Smith, P. | Bergamaschi, P. | Fowler, D. | Reis, S. | Centre for Ecology and Hydrology | Clean Fossil Fuels ; Energy Research Centre of the Netherlands (ECN) | Risø National Laboratory ; Danish Ministry of Science, Technology and Innovation | Institut für Meteorologie und Klimaforschung - Atmosphärische Umweltforschung (IMK-IFU) ; Karlsruher Institut für Technologie (KIT) | Environnement et Grandes Cultures (EGC) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech | Wageningen University and Research [Wageningen] (WUR) | Seconda Università degli Studi di Napoli = Second University of Naples | Unité de recherche Agronomie de Clermont (URAC) ; Institut National de la Recherche Agronomique (INRA) | University of Manchester [Manchester] | Agroscope | Royal Veterinary and Agricultural University = Kongelige Veterinær- og Landbohøjskole (KVL ) | Institut für Agrarekologie | Hungarian Meteorological Service (OMSZ) | Centre for Ecology and Hydrology [Bangor] (CEH) ; Natural Environment Research Council (NERC) | University of Amsterdam [Amsterdam] (UvA) | Center for Ecolological Research and Forestry Applications | Helsingin yliopisto = Helsingfors universitet = University of Helsinki | Danish Institute of Agricultural Sciences | Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE) ; Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) | Modélisation des Surfaces et Interfaces Continentales (MOSAIC) ; Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE) ; Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) | University of Aberdeen | JRC Institute for Environment and Sustainability (IES) ; European Commission - Joint Research Centre [Ispra] (JRC)
Recent research in nitrogen exchange with the atmosphere has separated research communities according to N form. The integrated perspective needed to quantify the net effect of N on greenhouse-gas balance is being addressed by the NitroEurope Integrated Project (NEU). Recent advances have depended on improved methodologies, while ongoing challenges include gas-aerosol interactions, organic nitrogen and N2 fluxes. The NEU strategy applies a 3-tier Flux Network together with a Manipulation Network of global-change experiments, linked by common protocols to facilitate model application. Substantial progress has been made in modelling N fluxes, especially for N2O, NO and bi-directional NH3 exchange. Landscape analysis represents an emerging challenge to address the spatial interactions between farms, fields, ecosystems, catchments and air dispersion/deposition. European up-scaling of N fluxes is highly uncertain and a key priority is for better data on agricultural practices. Finally, attention is needed to develop N flux verification procedures to assess compliance with international protocols
显示更多 [+] 显示较少 [-]Assessment of sediment concentration and nutrient loads in effluents drained from extensively managed fishponds in France
2008
Banas, Damien | Masson, Gérard | Leglize, L. | Usseglio-Polatera, Philippe | Boyd, C.E. | Unité de Recherches Animal et Fonctionnalités des Produits Animaux (URAFPA) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL) | Université Paris-Sud - Paris 11 (UP11) | Centre National de la Recherche Scientifique (CNRS) | AgroParisTech | Université Paul Verlaine - Metz (UPVM) | Auburn University (AU)
International audience | Expansion of aquaculture has increased concern over its environmental impact. The composition of effluents from intensive aquaculture is well documented, but few data on extensive aquaculture are available. During 12 draining operations, 523 water samples were collected downstream from six extensively-managed fishponds in northeastern France. Study ponds had surface areas of 2–620 ha and were managed for production of Cyprinids and Percids. Concentrations of total suspended solids, total phosphorus, and Kjeldahl nitrogen in effluents from the ponds were greatest during the final stage of draining. Loads of phosphorus were higher than those reported for effluents of more intensive aquaculture ponds in the USA, but the source of the potential pollutants was catchments and sediment rather than feeds and fertilizer. It will be necessary to reduce the water drawdown rate during the fishing stage and possibly implement other best management practices to prevent the TSS concentration from exceeding 1 g/L. Effluent phosphorus loads were higher than those reported for more intensive aquaculture ponds, but the pollutant source was catchments rather than feeds and fertilizers.
显示更多 [+] 显示较少 [-]Soil nutrients in a mature natural mixed forest exposed to elevated CO2
2002
Bucher-Wallin, I. K. | Schleppi, P. | Hagedorn, F. | Bucher, J. B. (Swiss Federal Research Institute WSL, Birmensdorf (Switzerland))
Elevated CO2 was shown to influence the nutritional status of exposed ecosystems. In an earlier experiment in model ecosystems in open-top chambers with young spruce and beech, the nitrate concentration of the soil solution was dramatically reduced after 4 years exposure to elevated CO2. This phenomenon was mainly interpreted as an immobilization of nitrogen in the soil. To test if such effects occur also in mature, undisturbed natural forests, we used facilities of the Swiss Canopy Crane project. Here in a mixed 120 years old forest the crowns of 30-35 m high broadleaved trees are fumigated with CO2 during the growing season since spring 2001. According to the results the soil is probably not yet much influenced by the fumigation of the tree crowns, and it is too early to estimate whether the observed nutrient effects are due to the CO2 treatment or to the natural variability of the soil
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