Effects Of Different Interplanting Patterns On Soil Microbial Community And Physical And Chemical Properties Of Young Camellia Oleifera Forest

Camellia oleifera Abel. is a special high-quality edible woody oil species in China, which has an important strategic position to solve the grain and oil security problem. However, young Camellia oleifera crown grow slow, no economic income, vegetation damaged and rain flushing action, which bring serious problem of soil erosion. Young Camellia oleifera forest intercropped is regarded as a reasonable forest management pattern, not only obtain early gains, also improve the soil fertility and promote the growth of Camellia oleifera tree, which is considered to be a legitimate business model. This paper, selecting 5 years young Camellia oleifera forest from MinHou Tongkong Forest farm as the research object, interplanting 6 different legume in young Camellia oleifera forest, namely interplanting with Cassia rotundifolia Pers, soybean, peanut, mungbean, cowpea and Chamaecrista nictitans, and comparison with interplanting with no crop, controlled different model by soil physical properties, soil nutrient and soil microbial community structure, aim to reveal the biological significance of interplanting, provided the scientific basis for select the best interplanting model. The main research results:(1) Six kinds of interplanting mode improve soil physical properties generally. In addition to the interplanting with mungbean mode’s soil moisture is lower than oil-tea monoculture mode, the rest planting patterns respectively improved soil moisture from 3.58% to 30.33%, soil fie moisture capacity from 3.20% to 11.34%, soil capillary water from 4.91% to 13.52%, soil maximum moisture capacity from 3.03% to 4.57%, soil total porosity from 1.55% to 13.61% and reduced soil bulk density from 0.10 g·cm3 to 0.24 g-cm3.(2) Monoculture mode’s organic matter is 13.48g·kg-1,6 species of legume interplanting organic matter among 14.53 g·kg-1 to 16.47 g·kg-1, which relived interplanting mode can increased organic matter. Compared to monoculture mode, soil total and available nitrogen, total and available phosphorus and total and available potassium were improved to vary degrees in the different interplanting modes, and the differences reached significant level(p<0.05). After interplanting have no obvious impact on soil pH value.Correlation analysis showed that soil organic was significantly correlated to total and available nitrogen and available potassium(p<0.01). Soil total nitrogen was significantly correlated to total and available phosphorus and available potassium. Also significant correlation between soil nutrient and soil physical properties, due to outcome of combined the soil nutrient, plant roots, and soil microbial.(3) This study detected 30 kinds of PLFA, showed oil-tea root zone soil microbial variety, including complete and incomplete distribution type. Common in different interplanting modes, 18:1 ω9c is the highest percentage PLFA monomer, as the absolute advantage feature phospholipid fatty acid groups. In different interplanting modes, the sum of 16:0、i16:0、18:0(characterization of bacteria) and 18:1ω9c、18:2ω6,9(characterization of fungi) were more than 50%, which showed these two kinds of microbial groups was a main role in soil of oil-tea root zone. The total PLFA, bacteria, fungi and gram-negative bacteria content were improved under different interplanting modes. Cluster analysis showed that interplanting mdel changed microbial community structure, and the changing of the interplanting with Cassia rotundifolia Pers mode is the biggest.Correlation analysis showed that soil organic and total and available nitrogen were positive significantly correlated to soil microbial groups, and soil microbial was positive significantly correlated to soil physical and chemical properties, which showed they were contact and influence each other between soil microbial and soil physical and chemical properties.(4) From soil microbial biomass, soil physical properties and soil nutrient analysis for comprehensive improvement of sorting:Camellia oleifera-Cassia rotundifolia Pers model> Camellia oleifera-Chamaecrista nictitans model> Camellia oleifera-peanut model> Camellia oleifera-cowpea model> Camellia oleifera-soybean model> Camellia oleifera-mungbean model>oil-tea monoculture model...