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A bacterial consortium, constructed from the oil contaminated soil, mainly consisting of Pseudomonas sp., together with fertilizing, rice husk application, and plowing, was used for the field in situ bioremediation of oil contaminated site in Jianghan Oil field, where the temperature and humidity are very suitable for bioremediation. The variation of total petroleum hydrocarbon, n-alkanes, and polycyclic aromatic hydrocarbons (PAHs) in the bioremediation process showed that more than 95% petroleum hydrocarbons could be efficiently removed. The composition analysis results demonstrated that n-alkanes with long carbon chain and PAHs with 5–6 rings were also degraded in the bioremediation process.

The effect of hydrostatic pressure on the crystal structure, electronic and optical properties of distorted rare-earth manganite TbMnO3 has been studied on the basis of first-principle calculations. The results reveal that the band gaps reduce quadratically with increasing pressure. The optical properties of TbMnO3 predict that the peaks in the dielectric function shift to higher photon energy due to the transformation of inner electronic states with increasing pressure. Otherwise, the peaks in the reflectivity spectra and loss function were also found to move to higher photon energy with pressure increasing and the relationships between the positions of these peaks and pressure can be fitted by third order polynomial expressions.

The ZnO thin films co-doped with Al and Sb have been successfully deposited by a sol–gel spin-coating method on glass substrates and annealed at different temperature for 2 h in air. The annealing effects of different temperature on the structure and biaxial stress were characterized by X-ray diffraction. The results revealed that the annealed ZnO thin films mainly consist of ZnO with wurtzite structure, and the biaxial stress is lower during annealed at 550 °C. The annealed films have high transmittance in the visible region and show sharp absorption edges in the UV region. The optical band gap Eg values are 2.95, 3.03, 3.18 and 3.15 eV, which corresponding to the films annealed at 450, 500, 550, 600 °C, respectively. The resistivity of thin films reaches a minimum when the annealing temperature at 550 °C. The conducting mechanism is contributed to Sb substitute for Zn inducing two corresponding Zn vacancies.

Pour evaluer le potentiel de reutilisation des eaux de drainage superficielles et souterraines en vue d'atteindre une production durable, la qualite de differentes eaux d'irrigation et les productions correspondantes obtenues par les agriculteurs utilisant ces eaux ont ete etudiees de facon suivie. La qualite de l'eau des drains et de la nappe phreatique (EC < 2 dS m -1 ) les designe comme favorables pour leur utilisation dans la majorite des municipalities de Huimin et Yangxin, tout en presentant quelques limitations en Wudy du fait d'une salinite cotiere plus elevee. Des fonctions de production en fonction de la salinite du sol pour le mais et le ble ont ete etablies; pour ce dernier ces fonctions dependent du nombre d'irrigations appliquees. Des simulations du modele SWAP montrent que les productions de mais et de ble peuvent etre maintenues en reutilisant les eaux de drainage si leur teneur en sel ne depasse pas 4 mg cm -3 . Il est clairement plus avantageux d'utiliser des eaux de drainage pour les deux dernieres irrigations du ble plutot que de pratiquer une irrigation deficitaire, et ceci en depit de la salinite des eaux. Les pluies de mousson devraient contribuer a maintenir un bilan de salinite favorable, donc a eviter que le sel s'accumule dans le profil du sol. Les resultats montrent que la reutilisation des eaux de drainage presente des avantages dans la gestion de l'eau d'irrigation, notamment pour les zones de production de ble ou l'eau est insuffisante.

The rapid development of industry and urban areas, population growth and rising living standards have all resulted in an increased water demand for non-agricultural uses in the North China Plain, therefore decreasing the water availability for irrigation. Technologies that favour a reduced demand and water-saving practices in irrigation are required to assure the sustainability of water use in agricultural production. This paper presents main research results relative to the integration of water and soil management technologies which may contribute to improving the use of water and land in agricultural production, reducing demand for irrigation, and more efficient use of groundwater. Improved estimates of crop irrigation requirements, better irrigation scheduling for the winter wheat crop and improved surface irrigation systems, result in water saving corresponding to about 100 mm in very dry years and up to 250 mm in average years with a small yield increase. These savings represent 16–33% of water use during the wheat crop season. Improvements in soil management lead to improved soil fertility and physical properties (including hydraulic conductivity). These improvements produce potential increases in summer maize yields of between 10 and 20%. Copyright © 2003 John Wiley & Sons, Ltd. Dans la Plaine du Nord de la Chine, le developpement rapide de l'industrie et des zones urbaines, la croissance de la population et l'amelioration de leur niveau de vie ont donne lieu a une demande en eau pour des usages non agricoles toujours accrue, ce qui a fortement diminue sa disponibilite pour l'irrigation. Des technologies qui favorisent la reduction de la demande agricole et l'economie d'eau en irrigation sont donc requises pour assurer la durabilite de l'utilisation de l'eau en irrigation. Cet article presente des resultats de recherche relatifs a la gestion de l'eau et du sol a l'echelle de la parcelle qui peuvent contribuer a ameliorer l'utilisation de l'eau et de la terre, la reduction de la demande et l'utilisation plus efficiente des eaux souterraines. En irrigation, les solutions proposees concernent l'estimation plus rigoureuse des besoins en eau des cultures irriguees, l'amelioration de la conduite des arrosages et la modernisation des systemes d'irrigation de surface, ce qui peut conduire a reduire la demande de 100 mm pour les annees de secheresse et jusqu'a 250 mm pour l'annee moyenne. Ces reductions representent a peu pres 16 a 33% de l'eau utilisee pour l'irrigation du ble, la principale culture irriguee dans la region. D'autre part, l'amelioration des pratiques de gestion du sol peut conduire a des effets positifs sur les proprietes hydrauliques et la fertilite du sol, ce qui pourrait conduire a augmenter la productivite du mais en pluvial de 10 a 20% dˆ tant a une meilleure utilisation des pluies d'ete qu'a des conditions de sol plus propices au developpement de la culture. Copyright © 2003 John Wiley & Sons, Ltd.