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181.
182.
The design of efficient water allocation systems depends, among other factors, on economic issues and, above all, on a reliable estimate of the economic value of water. In this paper the hedonic price method is utilized to reveal the implicit value of irrigation water by analyzing agricultural land values in Chalkidiki, a typical rural area in Greece. The method was applied to a sample of both irrigated and nonirrigated properties and the value of irrigation water was estimated by disaggregating the total price of each parcel of land, obtained through a local survey. Results show that, apart from typical value attributes, the agricultural characteristics of the land, including irrigation water availability, have a significant influence on land prices. 相似文献
183.
184.
Assessment of Soil Cover Degradation and Desertification in Northern Lowland Dagestan 总被引:2,自引:0,他引:2
Stasyuk N. V. Dobrovol'skii G. V. Zalibekov Z. G. Saidov A. K. Dobrynin D. V. 《Russian Journal of Ecology》2004,35(3):144-149
New principles of the assessment of soil cover degradation and desertification, the scale and intensity of destructive processes manifestation are determined. 相似文献
185.
Prioritization for Conservation of Northern European Cattle Breeds Based on Analysis of Microsatellite Data 总被引:2,自引:0,他引:2
186.
187.
Dissolved ions and suspended participates from twelve water samples from Sohag (different localities) and Aswan (behind and below the High Dam) areas were collected along the River Nile, upper Egypt, which is at present affected seriously by pressure of population, intense industrial and agricultural activities, and atmospheric fallout. Eighteen trace and nine major ions in solution and fourteen metals in suspension were analyzed to establish whether elements are of anthropogenic or natural origin. Results of this study show that the Nile water was contaminated with high concentrations of dissolved lead, and with copper, nickel and mercury to a lesser extent, suggesting that these contaminants are generated from anthropogenic activities. the other dissolved ions in the Nile are of natural origin because their metal concentrations fall within the range of the normal background and average world dissolved values for inland waters. Results show that the usual constituents of suspended particulates in the Nile seem to be some metals (Cu and Zn) adsorbed on iron and manganese oxide/hydroxide. the results also reveal that most trace and major metal particulates increase from south to north due to activities associated with the dense population living along the Nile banks. No significant differences were observed between the chemical composition of trace and major elements taken on the east and west river Nile banks. 相似文献
188.
Bevin Keen Ellen England Timothy Webb Summer Bartczak Charles Bleckmann 《补救:环境净化治理成本、技术与工艺杂志》2006,16(4):71-80
Environmental compliance requirements periodically impact the military's ability to use all installation resources. In response, environmental management strategies have been developed to ensure compliance and allow site closure. This study examines the relationship between environmental management strategies and environmental compliance at U.S. Marine Corps (USMC) installations via analysis of environmental compliance audit scores. Five environmental scores of interest from 1998 to 2004 audits—which include total compliance, total management, audit management, policy management, and training management—were subjected to statistical analysis. Results showed the USMC met environmental compliance and management standards, despite limited resources. High management strategy scores were moderately correlated with high total compliance scores. Total management scores improved over time, and noncompliance was most often associated with a lack of resources and plans. © 2006 Wiley Periodicals, Inc. 相似文献
189.
Sesbania rostrata in pure and amended Pb/Zn tailings. About 90% of seeds of S. rostrata germinated in pure Pb/Zn tailings, which contained high concentrations of Pb, Zn, Cu, and Cd. Although seedling growth suffered
from the adverse environment of Pb/Zn tailings, they became established on tailings stands, in the greenhouse, as well as
on the actual tailings dam, and completed their life cycle in 4 months. Dry matter production and nitrogen accumulation was
3200 kg/ha and 69.4 kg/ha, respectively in the actual tailings dam. Applying inorganic fertilizer to Pb/Zn tailings led to
no obvious improvement in growth and nodulation of S. rostrata, while tailings amended by river sediment or domestic refuse rich in organic matter improved the growth and nodulation of
the species. Azorhizobium caulinodans survived and formed N-fixing stem and root nodules in S. rostrata grown in pure Pb/Zn tailings with a nodule biomass exceeding 300 mg fresh matter per plant. 相似文献
190.
The ultrastructure of the genera Althornia, Aplanochytrium, Japonochytrium, Schizochytrium and Thraustochytrium is described, and all are regarded as members of the new order Thraustochytriales Sparrow. Species considered are Althornia crouchii, Aplanochytrium kerguelensis, Hyalochlorella marina, Japonochytrium sp., Schizochytrium aggregatum, Thraustochytrium kinnei and T. striatum. All but H. marina are, on ultrastructural evidence, related genera, and some speculative suggestions are made about possible interrelationships both between the species discussed, between the Thraustochytriales and Labyrinthulales, and between these two and other major taxa. 相似文献