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温度对大兴安岭北坡多年冻土湿地泥炭有机碳矿化的影响 总被引：1，自引：0，他引：1
温度是影响湿地土壤有机碳累积和分解的主要环境因子之一.通过室内培养实验分析温度对大兴安岭北坡连续多年冻土区湿地泥炭有机碳矿化的影响,其中采样点北极村、图强和壮林(52°45'～53°12'N,122°16'～122°46'E)位于大兴安岭的西北坡,而飞虎山和呼中(51°45'～52°09'N,122°57'～123°02'E)位于大兴安岭的东北坡.室内培养实验在4个温度梯度下(5℃,10℃,15℃和20℃)进行,湿地土壤有机碳矿化释放的CO2采用碱液吸收法测量.结果表明随着温度的升高,有机碳的矿化具有增加的趋势,在40天的培养期内,泥炭总的矿化量变化范围为 24.87～112.92mg/g; 同一温度下,泥炭矿化率随着培养时间具有先降低后稳定的趋势,两层泥炭(10～20cm和 20～30cm)对温度的响应趋势基本相同,不过表层泥炭的矿化率和矿化量要高于深层泥炭.有机碳矿化温度敏感性系数Q10值变化范围为 2.03～2.41,而深层泥炭的Q10值相对较大,表明冻土湿地深层泥炭对增温的响应也较敏感,并且大兴安岭东北坡冻土湿地的Q10值要大于西北坡的冻土湿地,表明大兴安岭东北坡的冻土湿地对于气候变暖的响应将更强烈.并且基于Q10值的二元动力学方程很好的反映了大兴安岭北坡冻土湿地泥炭矿化随温度和时间的动态变化. 相似文献
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Zhenying Liu Zhaohui Jin Yawei Li Tielong Li Jiujun Gu Si Gao 《Environmental Geology》2007,52(5):997-1005
Sediment phosphorus (P) fractions and profile distribution at submerged macrophyte growth zone, emergent macrophyte growth
zone and open-water zone were studied in Wuliangsuhai Lake, China, as well as the correlations among water content, grain
size, and organic matter and P fractions. Among the three surveyed zones, the highest concentrations of most P forms occurred
in the surface sediment and the lowest between a depth of 12 and 22 cm, except HCl-P and NaOH-P. Sediment phosphorus was mainly
associated to inorganic forms (>50%) in three surveyed areas, and the highest value of inorganic phosphorus (IP) in the surface
sediment was obtained from submerged macrophyte growth zone. Submerged and emergent macrophytes increased the IP content by
107 and 44 μg/g, respectively, in the surface sediment compared with open-water zone. Vertical profiles of IP in the three
surveyed zones showed that the concentrations decreased from surface to 12 cm depth and then increased. There was a similar
trend in the sediment profiles of organic phosphorus (OP) and total phosphorus (TP), but the highest concentration of OP and
TP in surface sediment was obtained from the emergent macrophyte growth zone. Compared with open-water zone, the emergent
macrophyte increased TP content in surface sediment by 1.73 times to 1,320 μg/g, while submerged macrophyte enhanced TP content
in the surface sediment by 1.13 times to 865 μg/g. It was observed that in macrophyte growth zones, a strong linear correlation
existed between organic matter and OP (r > 0.98), and the maximum concentrations of OP were present in the areas with maximum concentrations of organic matter. Results
show that, although rooted macrophyte could uptake directly P from sediments, it is responsible for increasing the internal
P loading especially OP by reducing current velocities, attenuating wave energy and generating organic residue in Wuliangsuhai
Lake. 相似文献
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边坡治理工程常用到喷锚支护形式。护坡面层采用素混凝土或者钢筋混凝土,耗用建材量大,不经济。公路边坡往往还需要环保观感要求,灰色的混凝土跟周围环境不协调。本文提出一种“锚杆加固+土工格栅护坡+客土喷播绿化”的新型生态边坡复合支护形式,并设计试验段进行研究。通过理正岩土软件计算,边坡稳定性、锚杆承载力均满足设计要求。试验段锚杆采用GFRP锚杆,面积100 m2。施工完成后,对比传统土钉墙混凝土面层和格构梁锚杆护坡支护形式,该形式具有施工快捷、经济适用等优势,既可用于加固边坡又具备绿色环保功能。 相似文献
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