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Change Characteristics of Soil Organic Carbon Pools under Different Management

Author: PengYing
Tutor: LiaoMin
School: Zhejiang University
Course: Soil
Keywords: Long-term fertilization Orchard grass Organic carbon pool Crop amount Dynamic characteristics
CLC: S153.6
Type: Master's thesis
Year: 2012
Downloads: 72
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Abstract

Fertilization test and orchard grass test by long-term positioning of the research, a systematic study of the impact of different land management on soil organic carbon and its component library, the analysis of the different components of organic carbon content, distribution, time series characteristics and analysis of the relationship between the different components of organic carbon pool and plant nutrients and yield, and to provide a theoretical basis for soil fertility to enhance and nurture the soil. The main findings are as follows: (1) long-term characteristics of different fertilization, soil organic carbon and its component library studies have shown that organic and inorganic fertilizers in soil organic carbon and microbial biomass carbon (SMBC), water-soluble organic carbon (of WSOC) light fraction organic carbon (LFOC) and its share of the proportion of total soil organic carbon were significantly higher than that of chemical fertilizer soil. Compared with no fertilizer, fertilizer than organic fertilizer more significant increase in soil restructuring the organic carbon (HFOC), and HFOC / TOC; organic fertilizer and chemical fertilizer were conducive to the larger grain size (gt; 250μm) and a smaller grain size (lt ; 250μm) water-stable aggregates TOC content. Therefore, the long-term application of organic fertilizer, especially organic fertilizer and inorganic fertilizer can improve soil active carbon content and soil aggregate stability, so as to maintain and improve the quality of the soil carbon pool and sustained productivity. And correlation analysis, the results show that the different components of soil organic carbon under long-term fertilization the of SMBC, WSOC, LFOC and POM-C can be used as early predictors reflect changes in soil organic carbon pool. (2) changes in the production of crop nutrients and bio-term fertilization. The results show that the the plants total N and total P total performance: grain gt; stems; Rice gt; barley. K as a whole; barley stems gt; rice stems gt; the Rice Grains gt; barley grain. Organic and inorganic fertilizer applied to improve the rice stalks and grain wholly-N, total P, total K content, organic fertilizer total N, total P greater than inorganic fertilizer, potassium less than inorganic fertilizers. Barley stalks and grain full N fertilization also reduce the total P, total K content, organic fertilizer processing three nutrient indexes content greater than inorganic fertilizer. Compared with CK, organic fertilizer and chemical fertilizer applied (except single N fertilization) are significantly increased biomass and grain yield of rice, organic fertilizer is more significant than increase the effect of inorganic fertilizer, which organic - inorganic fertilizer high single organic fertilizer, the high amount of inorganic fertilizer with manure higher than the low amount of inorganic fertilizer with organic fertilizer. In addition, we found that the single nitrogen treatment significantly reduced the biomass of rice. Visible, chemical fertilizer has a significant role to improve rice biomass. (3) analysis of soil organic carbon and its component library feature Taoyuan grass. The results indicate that the the orchard soil organic carbon content showed: the ryegrass treatment gt; clean tillage treatment gt; hairy vetch processing; compared to clean tillage treatment, orchard planting ryegrass and vetch, soil SMBC of WSOC significantly increased, which ryegrass increase compared with hairy vetch; the ryegrass to soil LFOC content than clean tillage decreased by 6.45%. Vetch 11.13%. Orchard pasture the soil HFOC content less than clean tillage. Ryegrass and vetch processing the than CK, respectively, 1.73% and 13.25%. Orchard grass and significantly improve soil aggregate content at all levels, including the largest increase for large aggregates (gt; 250μm) grain size and distribution of the impact of the organic carbon in aggregates, leading to changes in organic carbon content and aggregate content trend differences. Compared to clean tillage treatment, ryegrass treatment significantly increased the size of the aggregates of the soil organic carbon content (except lt; 74μm) the vetch treatment significantly reduced its content (except gt; 2000μm). (4) of orchard grass under the dynamic changes of soil organic carbon and its component library research. The results show that, soddy soil organic carbon as soddy time showed the highest spring summer and autumn content and lower in winter. This may be different because temperatures lead to different rate of organic matter decomposition. SMBC content in ryegrass and vetch two grass materials gradually increased; soil WSOC content: ryegrass gt; vetch, increase - lower - increased trend; processing soil LFOC concentration experienced ryegrass and clean tillage rise - down - up, vetch has been on an upward trend; ryegrass and vetch the soil treated HFOC concentration first rise maximum appears in sampled early (9.35g/kg), then has been declining. Clean tillage treatment at an early stage, has been in a rising trend, down to a minimum until the peach ceases; ryegrass and vetch can gradually improve all levels of aggregates of organic carbon content, which ryegrass compared vetch reached first maximum , which is related to their decomposition rate.

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CLC: > Agricultural Sciences > Agriculture as the foundation of science > Soil > Soil chemistry, soil physical and chemical > Soil composition
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