常德市土壤水分平衡指标定量计算研究

土壤水分平衡指标是衡量某一区域土壤水分状况的重要标志，正确掌握某一区域的土壤水分平衡指标．有利于该区农业生产的合理布局和各种农作物的合理配置。定量计算表明：常德市的几种主要土壤水分平衡指标为：年可能蒸散量Ep919mm，年实际蒸散量E．906mm，土壤年缺水量D13mm，土壤年余水量R473mm。通过对常德市全年土壤水分收支情况的分析，得到了较为满意的结果，为有关方面提供了借鉴材料。     

Spatial variation in soil inorganic nitrogen across an arid urban ecosystem

We explored variations in inorganic soil nitrogen (N) concentrations across metropolitan Phoenix, Arizona, and the surrounding desert using a probability-based synoptic survey. Data were examined using spatial statistics on the entire region, as well as for the desert and urban sites separately. Concentrations of both NO₃-N and NH₄-N were markedly higher and more heterogeneous amongst urban compared to desert soils. Regional variation in soil NO₃-N concentration was best explained by latitude, land use history, population density, along with percent cover of impervious surfaces and lawn, whereas soil NH₄-N concentrations were related to only latitude and population density. Within the urban area, patterns in both soil NO₃-N and NH₄-N were best predicted by elevation, population density and type of irrigation in the surrounding neighborhood. Spatial autocorrelation of soil NO₃-N concentrations explained 49% of variation among desert sites but was absent between urban sites. We suggest that inorganic soil N concentrations are controlled by a number of ‘local’ or ‘neighborhood’ human-related drivers in the city, rather than factors related to an urban-rural gradient.     

悬浮液进样石墨炉原子吸收光谱法测定土壤样品中微量硒

采用悬浮液进样石墨炉原子吸收光谱法测定土壤样品中微量硒，选用钯－抗坏血酸为基体改进剂、锆涂覆石墨管。以标准物质制作校正曲线等一系列措施，有效消防共存元素的干扰，并保证了标准系列与土壤样品的原子化条件的一致性，获得了满意的分析结果。     

ATSDR Science Panel on the Bioavailability of Mercury in Soils: Lessons Learned

On the basis of discussion and analysis during and following an ATSDR science panel on the bioavailability of mercury in soils, it is apparent that the default assumption of 100% relative bioavailability for mercury-contaminated soils is excessively conservative. However, current knowledge does not allow the development of default assumptions or guidelines for determining relative bioavailability of mercury in soils. Until such default assumptions or guidelines can be developed, site-specific assays of bioavailability, preferably using either animal bioassays or validated in vitro techniques, may provide the best approach for estimating soil-mercury bioavailability.     

宪法实践中的违宪形态研究

违宪是特定的宪法现象,其内涵是确定的。但在判定违宪与否的统一标准下,违宪的形态是多样的,如果以违宪主体为标准、以违宪行为为标准、以违宪作为行为为标准、以违宪审查的方法为标准进行分类,可以将其划分为不同的形态。对于良性违宪与恶性违宪、直接违宪与间接违宪、广义违宪与狭义违宪这些中国宪法学研究中出现过的违宪分类方法,则应从科学、规范的角度进行再分析。     

非法占有目的内涵之辨析

分析了大陆法系、英美法和中国大陆的各种观点,阐述了占有的含义、非法占有目的之规范结构、非法占有目的之心理构造、所有权能的组成和财产犯罪保护现状等。非法占有目的指向应是占有的本身,占有之下对财物的所有、使用和收益是比占有更深层的类似发起目的的心理动机,不属于占有目的的范畴。占有的本体事实和占有之下对财物更进一步处分的价值评价结合成非法占有目的的完整含义。     

Soil Nutrient Depletion and Population Growth in Sub-Saharan Africa: A Malthusian Nexus?

Soil nutrient mining and other forms of soil degradation threaten future soil productivity, especially in sub-Saharan Africa (SSA). Data from 36 countries in SSA show a significant relationship at the supra-national level between soil nutrient depletion (including erosion), reduced fallow periods, and population pressure and thus illustrate the unsustainable population-agriculture-environment nexus on the continent which so far has been described in case studies only. It appears that Malthusian mechanisms are at work, despite encouraging indications of farmers' concerns and adaptation to changing conditions. It is agreed that a re-examination of the common land degradation assessments and farmers' response to changing conditions would be useful, however, this should not delay other recommended interventions.     

通辽市近45年农业水资源变化分析

分析了通辽市近４５ 年降水、潜在蒸散及农田水分盈亏的变化,结果表明：年降水量在周期变化中具有减小的趋势,年降水量的稳定性增加,潜在蒸散波动上升。本世纪６０ 年代以来,春旱有所缓减,秋旱有所加剧     

土壤污染刑事责任探究

土壤污染是制约生态农业发展的罪魁祸首。制定《土壤污染防治法》对污染土壤的行为进行惩治,无疑是解决问题的一种最为有效的途径。立法最重要的问题是责任的明晰。法律责任有行政责任、民事责任和刑事责任,土壤污染刑事责任应当有别于其他污染。在立法模式上,土壤污染的刑事责任应当既在刑法中规定,也在土壤污染防治法中进行规定。     

沉井冲水掏土纠偏技术的工程应用

软粘土地基处理的方法很多 ,其中对已有倾斜建筑物地基处理的技术难度较大 .本文介绍了在工程实际应用的一种新方法 :沉井冲水掏土纠偏法