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931.
Rachèl V. van Schendel G. C. Page-Christiaens Lean Beulen Catia M. Bilardo Marjon A. de Boer Audrey B. C. Coumans Brigitte H. Faas Irene M. van Langen Klaske D. Lichtenbelt Merel C. van Maarle Merryn V. E. Macville Dick Oepkes Eva Pajkrt Lidewij Henneman for the Dutch NIPT Consortium 《黑龙江环境通报》2016,36(12):1091-1098
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V. A. Romanenkov J. U. Smith P. Smith O. D. Sirotenko D. I. Rukhovitch I. A. Romanenko 《Regional Environmental Change》2007,7(2):93-104
The Model of Humus Balance was used to estimate the influence of climate effects and changing agricultural practices on carbon
(C) levels in soddy–podzolic soils in the Russian Federation for the years 2000–2050. The model was linked with a spatial
database containing soil, climate and farming management layers for identification of spatial change of C sequestration potential.
Analysis of relationships between C, soil texture and climate indicated that compared with a business-as-usual scenario, adaptation
measures could increase the number of polygons storing soil organic carbon (SOC) by 2010–2020. The rate of possible C loss
is sensitive to the different climate scenarios, with a maximum potential for SOC accumulation expected in 2030–2040, thereafter
decreasing to 2050. The effect is most pronounced for the arid part of the study area under the emission scenario with the
highest rate of increase in atmospheric CO2 concentration, supporting findings from the dynamic SOC model, RothC. C sequestration during the study period was permanent
for clay and clay loam soils with a C content of more than 2%, suggesting that C sequestration should be focused on highly
fertile, fine-textured soils. We also show that spatial heterogeneity of soil texture can be a source of uncertainty for estimates
of SOC dynamics at the regional scale.
Figures in color are available at 相似文献
935.
There is inconsistency in many people's choice of electricity. When asked, they say they prefer a ‘green’ (i.e., environmentally friendly) source for this energy. Yet, although green electricity is available in many markets, people do not generally buy it. Why not? Motivated by behavioural decision research, we argue that the format of information presentation drastically affects the choice of electricity. Specifically, we hypothesise that people use the kind of electricity that is offered to them as the default. We present two natural studies and two experiments in the laboratory that support this hypothesis. In the two real-world situations, there was a green default, and most people used it. In the first laboratory experiment, more participants chose the green utility when it was the default than when ‘grey’ electricity was the default. In the second laboratory experiment, participants asked for more money to give up green electricity than they were willing to pay for it. We argue that changing defaults can be used to promote pro-environmental behaviour. Potential policy-making applications of this work are discussed. 相似文献
936.
Trends in plant cover synanthropization along a plain-foothills-mountains gradient have been revealed in the reserve. Characteristics of plant communities in anthropogenically disturbed habitats, centers of concentration of anthropophytes and apophytes, and pathways of their migration are described. 相似文献
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Abstract: Nongame bird hunting is a critical activity of the Zuni people of the southwestern United States. To help determine whether their current hunting practices may be negatively affecting bird populations on the Zuni Reservation, we interviewed 98 Zuni hunters. Nongame bird hunting was practiced by a large portion of Zuni males (45%); the most active age group was 20- to 49-year-olds. The rate a species was hunted was not a function of its abundance at Zuni but seemed instead to be related to its cultural demand. Five "species"—bluebirds ( Sialia currucoides , S. mexicana ), Northern Flicker ( Colaptes auratus ), woodpeckers ( Picoides villosus , P. pubescens , Melanerpes lewis ), Steller's Jay ( Cyanocitta stelleri ), and American Kestrel ( Falco sparverius )—made up 77% of all birds taken. The two most heavily hunted species were each taken in numbers> 10,000 individuals per year. Although the greatest number of hunters were active in autumn, 31% hunted in spring, despite discouragement by the tribal government. Habitats favored by hunters were coniferous forests and riparian areas. Rates of hunting of nongame birds at Zuni equaled or exceeded those reported for game birds hunted by indigenous hunters in the Neotropics and New Mexico. The Zuni believe that some heavily hunted species are decreasing in number because of hunting. Although we cannot prove this at present, we suggest measures to mitigate possible overhunting, including the creation of refugia and a reduction of spring hunting. 相似文献
940.
Jeffrey R. Brook Leiming Zhang Yifan Li David Johnson 《Atmospheric environment (Oxford, England : 1994)》1999,33(30):804
Numerical sensitivity tests and four months of complete model runs have been conducted for the Routine Deposition Model (RDM). The influence of individual model inputs on dry deposition velocity as a function of land-use category (LUC) and pollutant (SO2, O3, SO2−4 and HNO3) were examined over a realistic range of values for solar radiation, stability and wind speed. Spatial and temporal variations in RDM deposition velocity (Vd) during June – September 1996 time period generated using meteorological input from a mesoscale model run at 35 km resolution over north-eastern North America were also examined. Comparison of RDM Vd values to a variety of measurements of dry deposition velocities of SO2, O3, SO2−4 and NHO3 that have been reported in the literature demonstrated that RDM produces realistic results. Over northeastern NA RDM monthly averaged dry deposition velocities for SO2 vary from 0.2 to 3.0 cm s−1 with the highest deposition velocities over water surfaces. For O3, the monthly averaged dry deposition velocities are from 0.05 to 1.0 cm s−1 with the lowest values over water surfaces and the highest over forested areas. For HNO3, the monthly averaged dry deposition velocities have the range of 0.5 to 6 cm s−1, with the highest values for forested areas. For SO2−4, they range from 0.05–1.5 cm s−1, with the lowest values over water and the highest over forest. The monthly averaged dry deposition velocities for SO2 and O3 are higher in the growing season compared to the fall, but this behaviour is not apparent for HNO3 and sulphate. In the daytime, the hourly averaged dry deposition velocities for SO2, O3, SO2−4 and HNO3 are higher than that in the nighttime over most of the vegetated area. The diurnal variation is most evident for surfaces with large values for leaf area index (LAI), such as forests. Based on the results presented in this paper, it is concluded that RDM Vd values can be combined with measured air concentrations over hourly, daily or weekly periods to determine dry deposition amounts and with wet deposition measurements to provide seasonal estimates of total deposition and estimates of the relative importance of dry deposition. 相似文献