摘要
研究了重金属污染裸地植被恢复4、5、6a和7a后的植物凋落物积累量、土壤化学特征、重金属含量与土壤微生物特征。结果表明:与未恢复裸地相比,植被恢复显著地提高了根际土壤中的有机碳(18.6—31.1g·kg^-1)、总氮(0.88—1.56g·kg^-1)和总磷(0.34—0.39g·kg^-1)含量(P〈0.05);上述指标以及植物凋落物积累量没有随植被恢复年龄增加而提高。植被恢复地土壤pH、重金属铅、锌、铜的总量和DTPA(diethylenetriaminepentaacetic acid)可提取量均显著地高于未恢复裸地(P〈0.05),并且随植被恢复年龄增加呈现出一致提高的趋势。土壤微生物量碳和氮在5个研究样地中的变化趋势基本一致,即最大值均出现在样地RV(恢复5a)(127.34mg·gdw^-1和2.45mg·gdw^-1),然后在样地RVI(恢复6a)和RVII(恢复7a)均有不同程度地下降。微生物量氮在4个恢复样地中变化显著(P〈0.05)。土壤微生物基础呼吸和功能多样性最大值发生在样地RVI(59.10mg·gdw^-1和3.14),随后在样地RVII中略有下降(P〉0.05)。未恢复裸地的土壤微生物对羧酸和胺类化合物利用率显著大于4个恢复样地(P〈0.05),对碳水化合物、氨基酸、聚合物和杂合物的利用率显著低于4个恢复样地(P〈0.05)。主成分分析结果表明,未恢复裸地的CLPP(community level physiological profiles)指纹与恢复样地存在显著差异(P〈0.05),4个恢复样的CLPP指纹相似。
Litter accumulation, soil-chemical parameters, heavy metal contents and soil-microbial properties after the revegetation of the barren land contaminated with heavy metals were investigated. The results showed that, the re-vegetation could significantly increase soil organic carbon ( 18.6 - 31.1 g·kg^-1 ) , total nitrogen (0.88 - 1.56 g·kg^-1 ) and total phosphorus (0.34- 0.39 g·kg^-1) in rhizosphere soils compared with the barren land. However, the litter accumulation and the above indicators did not consistently increase with the re-vegetation ages. Soil pH, the total amount of Pb, Zn and Cu and DTPA-extractable Pb, Zn and Cu in the re-vegetated soils were significantly (P 〈 0.05 ) higher than those in the barren land, and linearly increased with the re-vegetation age. The RV site had the highest levels in both soil-microbial biomass carbon and nitrogen ( 127.34 mg·gdw^-1 and 2.45 mg·gdw^-1 ). There was a significantly ( P 〈 0.05 ) different decline in microbial biomass nitrogen in the RVI and RVII sites. The RVI site had the highest levels in soil basal respiration and functional diversity (59.10 mg·gdw^-1 and 3.14) and there was a decline in the RVII site. Both the basal respiration and functional diversity had no significant difference among the four re-vegetated sites. Soil-microbial community in the barren land had a greater utilization in carboxylic acids and amines/amides, and lower utilization in carbohydrates, amino acid, polymers and miscellaneous than those in the four re-vegetated sites (P 〈 0.05 ). The PCA (principal components analysis) showed that CLPP (community level physiological profiles) in the barren land was significantly (P 〈 0. 05 ) distinct from the re-vegetated sites, but had no significant difference among the four re-vegetated sites.
出处
《生态学报》
CAS
CSCD
北大核心
2009年第3期1636-1646,共11页
Acta Ecologica Sinica
基金
浙江省自然科学基金资助项目(Y507053)
台州学院博士启动基金资助
关键词
退化裸地
植被恢复
土壤微生物量
土壤基础呼吸
功能多样性
degraded barren land
re-vegetation
soil microbial biomass
soil basal respiration
functional diversity