Mapping critical loads of sulfur and nitrogen for soils in Zhanjiang
Journal Title: Science Paper Online - Year 2007, Vol 2, Issue 7
Abstract
Supported by the geographical information system (GIS), critical loads of sulfur and nitrogen of soils in Zhanjiang area, Guangdong province were estimated through the steady state method. According to the critical loads of sulfur, the area can be divided into three parts, with high values (>5.0 keqhm-2a-1) in the northern and southern ones where coniferous/ broadleaf-conifer-mixed forest and cultivated vegetation are distributed respectively, and low values (<1.0 keqhm-2a-1) in the middle one where broadleaf forest is dominated. The distribution pattern of critical loads of sulfur coincides well with that of vegetation, because the spatial variation of the uptake rates of base cation by vegetation are much more significant than that of the weathering rates of soils in the area. In comparison with the critical loads of sulfur, the critical loads of nitrogen are commonly high (>5.0 keqhm-2a-1) as a results of abundant vegetation and thus high uptake rates of nitrogen by vegetation. It is estimated that critical loads have been exceeded by sulfur deposition or nitrogen deposition in more than half of the area, most of which occurs in broadleaf forest in the middle part with only sulfur exceedance. In addition, the nitrogen exceedance occurs mainly in coniferous/broadleaf-conifer-mixed forest in the northern part.
Authors and Affiliations
Lei Duan, Xianbo Xian, Pixue Li
Keywords
Related Articles
- EP ID EP102237
- DOI -
- Views 102
- Downloads 0
Critical diffusible hydrogen concentration for blistering of a micro-alloyed clean wheel steel
The critical diffusible hydrogen concentration for hydrogen blistering of a micro-alloyed clean wheel steel was measured using the electrolytic hydrogen charging method. The results show that the diffusible hydrogen conc...
阿司匹林临床应用现状及局限性
阿司匹林是抗血小板治疗的经典药物，在心脑血管系统疾病应用最多，但近年来关于阿司匹林抵抗的报道渐多，本文主要对阿司匹林应用现状及阿司匹林抵抗研究最新进展进行了概述，并对中医药在抗血小板应用前景进行了分析。
多乙烯多胺类膏体含能材料的制备与热性能表征
本文介绍以多乙烯多胺与硝酸盐为原料合成制备一种新型的膏体含能物质的方法。利用红外测试对产物的结构进行表征、DSC和TGA对产物的性能进行表征。红外测试表明无机盐与多烯多胺反应生成一种稳定的含能产物。DSC和TGA表明该产物热性能稳定...
Kinetics models of Fischer-Tropsch synthesis<br /> on the cobalt-based catalyst<br />
The activated phases were Co for the cobalt-based catalyst. The production of CO2 was trace, the reaction for the water gas shift was ignored. Formed hydrocarbon reaction was the main reaction of Fischer-Tropsch synthesi...
The synthesis of MFI zeolite membrane on large H-ZSM-5 crystal
Using in-situ hydrothermal synthesis to prepare large H-ZSM-5 crystal and the MFI zeolite membrane was synthesized on it. The X-ray diffraction (XRD), optical microscope, scanning electron microscope (SEM) and Uv-vis dif...