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Moso bamboo (Phyllostachys Pubescens) expansion into adjacent forests has been widely reported to affect plant diversity and its association with mycorrhizal fungi in subtropical China, which will likely have significant impacts on soil respiration. However, there is still limited information on how Moso bamboo expansion changes soil respiration components and their linkage with microbial community composition and activity. Based on a mesh exclusion method, soil respirations derived from roots, arbuscular mycorrhizal (AM) mycelium, and free-living microbes were investigated in a pure Moso bamboo forest (expanded), an adjacent broadleaved forest (nonexpanded), and a mixed bamboo-broadleaved forest (expanding). Our results showed that bamboo expansion decreased the cumulative CO2 effluxes from total soil respiration, root respiration and soil heterotrophic respiration (by 19.01%, 30.34%, and 29.92% on average), whereas increased those from AM mycelium (by 78.67% in comparison with the broadleaved forests). Bamboo expansion significantly decreased soil organic carbon (C) content, bacterial and fungal abundances, and enzyme activities involved in C, N and P cycling whereas enhanced the interactive relationships among bacterial communities. In contrast, the ingrowth of AM mycelium increased the activities of β-glucosidase and N-acetyl-β-glucosaminidase and decreased the interactive relationships among bacterial communities. Changes in soil heterotrophic respiration and AM mycelium respiration had positive correlations with soil enzyme activities and fungal abundances. In summary, our findings suggest that bamboo expansion decreased soil heterotrophic respiration by decreasing soil microbial activity but increased the contribution of AM mycelial respiration to soil C efflux, which may potentially increase soil C loss from AM mycelial pathway. [ABSTRACT FROM AUTHOR]

Bamboo is widespread in the subtropics and tropics of Asia, Africa, and Latin America. The total area of bamboo forests of various species is 22.0 × 10 ha, accounting for about 1.0% of the total global area of forest. Although the total forest areas in many countries have decreased drastically, bamboo forests have increased at a rate of 3% annually. China has the richest resources of bamboo in the world, with over 500 species in 39 genera. Carbon storage of vegetation, soils, and litter in bamboo forest system in China was 0.2511 × 10, 0.8516 × 10, and 0.0361 × 10 g C, respectively, giving a total of 1.1388 × 10 g C. This paper reviews carbon storage of vegetation, soils, and litter in bamboo forest system and compares the carbon fixation abilities of bamboo forest ecosystems with those of other tree species in subtropical China. [ABSTRACT FROM AUTHOR]

Selection and development of tree species with high fixing CO capacity is an increasing problem worldwide. A comparative study on carbon fixation ability of three forest stands was conducted at Linlong Mountain, Li'nan County, Zhejiang Province, China. The results showed that total carbon storage in the ecosystems of Moso bamboo, Chinese fir, and Masson pine stands were 104.83, 95.66, and 96.49 t C/ha, respectively. The spatial distribution of carbon storage in the three ecosystems decreased in the order: soil > tree story > the vegetation under the forests. Carbon storage in the soils under Moso bamboo, Chinese fir, and Masson pine stands accounted for 65.3, 61.4, and 55.6% of the total CSs, respectively. The Moso bamboo forest ecosystem fixed 1.69 and 1.63 times as much C (9.64 t C/ha/year) as the Chinese fir and Masson pine forest ecosystems, respectively. [ABSTRACT FROM AUTHOR]

Area of bamboo forest ( Phyllostachys praecox) has rapidly increased in southern China during the last 20 years due to its high economic value. Aims of this study were to analyse the temporal and spatial variations of soil organic matter (SOM) in heavily winter mulched bamboo stands and to estimate potential for carbon sequestration. Total of 60 soil profiles with 0-15 years of bamboo plantation were sampled from three towns in Lin'an County. Results showed that with increased plantation years, SOM decreased slightly at the beginning (1-5 years), and then rose up steadily. Based on the average of the three locations, the highest SOM content of 75.82 g/kg was the surface layer (0-10 cm) of the 15 years. As plantation year increased, the variation of SOM in the surface layer (0-10 cm) was represented by a parabolic shape, and in the second layer (10-20 cm), it was a similar mode, but less vigorous. Soil organic carbon (SOC) storage significantly increased during 5 to 15 years after it reached full production, and the calculated annual SOC increment in 0-40 cm soil profile was about 6.3 t C/ha/year. Therefore, extended Phyllostachys praecox forests can be considered as one option for countering CO emissions and regional climate change. [ABSTRACT FROM AUTHOR]

Purpose The bamboo species Phyllostachys praecox has been planted in large areas of southern China for the production of edible bamboo shoots. In recent years, high rates of fertilizer application and heavy winter mulch have been employed to achieve an earlier harvest of the shoots and a better economic return. Little is known about the potential impact of these intensive management practices on the receiving environment. Therefore, a field experiment was conducted to quantify the effect of winter mulch on soil CO2 efflux, which contributes to greenhouse gas emissions. Materials and methods The field study was established in 6-year-old P. praecox stands for the period between December 2006 and February 2007 in Lin'an County, Zhejiang Province, China. The treatments included a 200- mm mulch with rice straw and rice husks, and a control without mulch. Soil CO2 efflux rates and soil temperature changes were measured monthly and comparisons were made between the treatments. Results and discussion Soil CO2 efflux rates in the mulch treatment were 10.98 and 4.27 μmol m-2s-1 in December 2006 and January 2007, respectively, which was eight times greater than soil CO2 efflux rates measured in the nonmulch control treatment in the corresponding months. The significantly higher temperature and increased dissolved organic carbon in the mulch treatment were considered to have contributed to the enhanced soil CO2 emission. Conclusions Heavy winter mulch in a P. praecox plantation can greatly enhance soil respiration rates due to increases in both soil temperature and readily mineralizable labile organic matter. The increased CO2 emissions from soil respiration under winter mulch treatments can potentially reduce the greenhouse gas emission mitigation function of the bamboo forest plantations. It is recommended that new management practices be developed to alleviate the impacts of winter mulch on the environment. [ABSTRACT FROM AUTHOR]

Background, aim, and scope Bamboo (Phyllostachy pubescens Mazel ex Lehaie), a unique fast-growing tree species, is an important forest resource in southern China. Because of its high economic value and short rotation period, intensive management practices such as fertilization, weeding, and deep tilling are extensively utilized. These practices significantly increase the production of mature timber and young shoots. In this paper, bamboo stands under intensive management with short-term (STIP) and long-term (LTIP) practices were compared with those managed conventionally (CON) to study the effects of intensive management practices on soil biological properties. Materials and methods We measured the soil microbial biomass carbon (MBC), basal respiration carbon (BRC), and the specific ability of soil microbiota to consume a range of carbon (C) substrates, measured by Biolog ECU MicroPlate. Results Intensive management practice significantly decreased (P<0.05) soil MBC (in the order of CON > STIIP> LTIP), but increased soil BRC (in the order of STIP LTIP > CON). Under intensive management practices, soil microbial activity, and diversity of C sources utilized by microbial communities decreased (P<0.05), as characterized by average well color development (AWCD). Shannon and McIntosh indexes tended to decline with intensive management practices. Intensive management practice also caused much lower (P<0.05) utilization of 2-hydroxy benzoic acid and a-cyclodextrin. Discussion Soil biological properties were proved to be sensitive indicators of soil quality in response to the intensive management practices, with decreases in soil MBC, microbial activity, and diversity of C sources utilized by microbial communities under the continuing intensive management practices in bamboo stands. This indicates that the intensive management practices had resulted in the negative effect on the soil microbial activities. Conclusions Intensive management practices generally had a negative influence on the soil biological properties. This would have important implications for the sustainable management of bamboo production systems in southern China. Recommendations and perspectives To minimize the detrimental effect on soil microbial communities, an improved intensive management practice with reducing amounts of mineral fertilizer and increasing organic fertilizer applications are recommended annually so that both high bamboo yield and soil quality can be sustained over a long period. [ABSTRACT FROM AUTHOR]

Three field experiments at three sites in east Zhejiang Province were conducted to determine the influence of applications of boron (B) on growth, yield, and quality of the red bayberry trees (Myrica rubra Sieb. et Zuca) with a manure species of "Buqizhong" in Linhai city. Ground B application or foliar B spraying significantly improved length and incidence rates of spring and summer shoots and increased fruit set rates, which resulted in the increases in fruit yield (13.7-17.5% for ground B application or 13.2-27.3% for foliar B spraying) and in improvement of fruit quality. The optimum yields were recorded with the treatments of ground B application of 40 g tree-1 of borax or foliar B spraying of 2.0 g L-1 of borax. Spring shoot incidents for the treatment of ground application of 50 g borax tree-1 every year during the experiment (4B50) were significantly higher than that for the treatment of ground application of 50 g borax tree-1 only in the first year of the experiment (B50), but the yield difference between them was not significant at P = 0.05. The increased yield effect of ground B application could last for 3 years. Boron application of red bayberry trees can be carried out by foliar-spraying 2.0 g borax L-1 every year or ground application of 50 g borax tree-1 every 3 years. The results of this study showed that application B could significantly improve the growth and increased fruit yield and quality of the red bayberry trees not exhibiting any vegetative symptoms of B deficiency. [ABSTRACT FROM AUTHOR]