Soil organic carbon fractions as influenced by vegetation type and land management: A case study in semiarid rangelands of Hamedan, Iran

Authors : Khadijeh Salari NİK, Mohsen NAEL, Ghasem ASSADİAN, Ali Akbar Safari SİNEGANİ, Soheila Javaheri KHA

Pages : 76-81

Doi:10.18393/ejss.34853

View : 16 | Download : 6

Publication Date : 2015-03-18

Article Type : Research Paper

Abstract :Soil is an environmental component permanently changing due to the often cyclic processes of litter supply and vegetation cover. To investigate the influence of vegetation type on soil carbon fractions, six vegetation types, including rainfed wheat insert ignore into journalissuearticles values(RW);, grasses insert ignore into journalissuearticles values(G);, Astragallus–Bromus insert ignore into journalissuearticles values(A-B);, Astragallus–lactuca insert ignore into journalissuearticles values(A-L);, Astragallus–Artemisi insert ignore into journalissuearticles values(A-A);, Astragallus–Euphorbia insert ignore into journalissuearticles values(A-E); were studied in similar environmental conditions in terms of parent material and slope aspect in Gonbad watershed, Hamadan. Total organic carbon insert ignore into journalissuearticles values(TOC);, active carbon insert ignore into journalissuearticles values(AC);, soil carbohydrates insert ignore into journalissuearticles values(Ch); and basal respiration insert ignore into journalissuearticles values(BR); were measured in surface soils insert ignore into journalissuearticles values(0-15 cm); in fall and spring. TOC, CH, and BR were significantly greater in A-B and A-A than other covers. A-B and A-A showed higher vegetation cover and litter compared to other types. TOC and Ch in RW and G were significantly lower than other types. The highest insert ignore into journalissuearticles values(711.7 mg/kg); and lowest insert ignore into journalissuearticles values(262.6 mg/kg); AC were observed in A-B and RW, respectively. RW had lowest values of selected soil quality indicators due to tillage and cultivation. The content of TOC and AC were significantly higher in spring than autumn. Amount of BR and Ch showed no significant difference in the two seasons. Significant positive correlations were observed between soil quality indicators, these correlations were stronger in spring than in autumn. In autumn, the highest correlations were observed between AC and Ch insert ignore into journalissuearticles values(0.701);, as well as AC and BR insert ignore into journalissuearticles values(0.441);. In spring, significant correlations were observed between all soil quality indicators at 1% level. It was concluded that AC and Ch are the most sensitive soil quality indicators that reflect land use and vegetation type differences.
Keywords : soil quality, vegetation type, active carbon, carbohydrate