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Phytolith-occluded carbon (PhytOC) with high resistance against decomposition is an important carbon (C) sink in many ecosystems. This study compared concentrations of phytolith in plants and the PhytOC production of seven sympodial bamboo species in southern China, aiming to provide the information for the managed bamboo plantation and selection of bamboo species to maximize phytolith C sequestration. Leaf litters and living leaves of seven sympodial bamboo species were collected from the field sites. Concentrations of phytoliths, silicon (Si), and PhytOC in leaf litters and living leaves were measured. Carbon sequestration as PhytOC was estimated. There was a considerable variation in the PhytOC concentrations in the leaf litters and living leaves among the seven bamboo species. The mean concentrations of PhytOC ranged from 3.4 to 6.9 g kg(-1) in leaf litters and from 1.6 to 5.9 g kg(-1) in living leaves, with the PhytOC production rates ranging from 5.7 to 52.3 kg e-CO2 ha(-1) year(-1) as leaf litters. Dendrocalamopsis oldhami (Munro) Keng f. had the highest PhytOC production rate. Based on a bio-sequestration rate of 52.3 kg e-CO2 ha(-1) year(-1), we estimated that the current 8 × 10(5) ha of sympodial bamboo stands in China could potentially acquire 4.2 × 10(4) t e-CO2 yearly via phytolith carbon. Furthermore, the seven sympodial bamboo species stored 5.38 × 10(5) t e-CO2 as PhytOC in living leaves and leaf litters in China. It is concluded that sympodial bamboos make a significant contribution to C sequestration and that to maximize the PhytOC accumulation, the bamboo species with the highest PhytOC production rate should be selected for plantation.

Phytolith-occluded organic carbon (PhytOC) is an important long-term (up to several thousand years) terrestrial carbon (C) fraction in forest ecosystems. The objectives of this study were to (i) investigate the spatial distribution of PhytOC in Lei bamboo (Phyllostachys praecox C.D. Chu & C.S. Chao.) forests under intensive management (mulching and fertilization) and (ii) assess the role of PhytOC in C sequestration in a Lei bamboo stand and across subtropical China. Phytolith concentrations in Lei bamboo plant components were (P < 0.05) in the following order: rhizome ≈ stump > leaf ≈ branch > culm. The distribution of PhytOC in bamboo leaves, branches, culms, rhizomes, and stumps was 22.2%, 12.1%, 16.1%, 15.9%, and 33.7%, respectively. The PhytOC stock was in the following order (P < 0.05): soil (9361 kg C·ha−1) > mulching materials (197.5 kg C·ha−1) > belowground plant parts (13.0 kg C·ha−1) ≈ aboveground plant parts (12.8 kg C·ha−1) ≈ litterfall (11.3 kg C·ha−1). The PhytOC accretion rate in the vegetation in the Lei bamboo stand was 19.4 kg C·ha−1·year−1, equivalent to 71 kg CO2-eq·ha−1·year−1. The soil PhytOC stock decreased markedly with depth and had an accretion rate of 325 kg C·ha−1·year−1 for the 0–60 cm soil layer. Based on a PhytOC accretion rate of 0.795 Mg CO2-eq·ha−1·year−1, PhytOC accretion rate in the 2.62 × 106 ha of Lei bamboo stands in southern China is estimated to be 2.08 × 106 Mg CO2-eq·year−1. In conclusion, intensively managed Lei bamboo stands have a large potential in long-term C sequestration in the form of PhytOC, and the PhytOC stock belowground should not be ignored due to its contribution to the ecosystem level PhytOC stock.

The results of a three-year field experiment showed that boron application significantly increased spring shoot length, spring shoot incidence, leaf area, and uptake of N, P, and K in red bayberry (Myrica rubra Sieb. et Zuca). Soil application of boron gave a significantly higher fruit yield than foliar application of boron in 2009 and 2008. On average, over three years the increases in uptake amounts of N, P, and K as well as fruit yield were in the following order: soil application of boron every year > foliar B application every year > soil B application only in the first year > foliar B application only in the first year.

Shoot dieback characterized by leaflet, rosette shoots, and dieback of shoot tips is one of the most important problems in red bayberry production in south China. However, the causes of shoot dieback have not been determined. The results of leaf analysis and correction experiment showed that leaf boron (B) concentrations were highly correlated with leaf area (P < 0.01), spring shoot length (P < 0.01), and spring shoot numbers sprouting from one old shoot (P < 0.05). Foliar application of B at 2.0 g L–1 of borax was more effective on correcting shoot dieback than foliar application of Zn at 2.0 g L–1 of zinc sulfate and of molybdenum (Mo) at 2.0 g L–1 of ammonium molybdate. Boron application increased fruit yields by 1.23–2.15 times compared with the control. Shoot dieback resulted mainly from B deficiency in the red bayberry trees.

Alternate bearing, resulting mainly from boron (B) deficiency, and excessive fruits in the alternate years of red bayberry trees are the most important limiting factors for production. This investigation was conducted on 18-year-old Muye red bayberry trees (Myrica rubra Sieb. et Zuca) in a commercial red bayberry orchard located in Laxi County, Zhejiang Province in 2006–2007.The results indicated that foliar application of paclobutrazol (PB) significantly increased the vegetative growth parameters (i.e., spring shoot incident and spring shoot length). Spring shoot incidents and spring shoot lengths of red bayberry were increased with increasing PB concentrations, but the optimum fruit yield and quality were obtained from foliar-applied PB at 100–200 mg L−1 at full bloom. Foliar application of PB increased the contents of N and K in the leaves with increases of PB concentrations up to 300–600 mg L−1. Fruit quality of red bayberry trees treated with PB or and boron fertilizer (BF) was improved at full bloom...

Selection and development of tree species with high fixing CO2 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.

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 × 106 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 × 1015, 0.8516 × 1015, and 0.0361 × 1015 g C, respectively, giving a total of 1.1388 × 1015 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.

Chinese hickory (Carya cathayensis Sarg.) is a woody nut and oil tree from China. Intensive management including heavy application of chemical fertiliser and long-term application of herbicides has resulted in serious soil loss and degradation. This study aimed to test the hypothesis that intercropping in the soil under Chinese hickory stands may improve soil fertility and microbial community functional diversity. A field experiment consisting of four treatments (clean tillage; intercropping rape (Brassica rapa L.), ryegrass (Lolium perenne L.) or Chinese milk vetch (Astragalus sinicus L.) was conducted to study the effects of intercropping on soil organic carbon (SOC) structure and microbial community functional diversity under C. cathayensis stand, by means of 13C-nuclear magnetic resonance (NMR), and EcoPlates incubated at 25°C. After 4 years of treatment, intercropping increased available nitrogen (N), phosphorus and potassium in the soil by 25.1–54.2, 4.2–6.0 and 0–22.5 mg kg–1, respectively, relative to the clean tillage treatment; intercropping rape, ryegrass and Chinese milk vetch increased SOC, microbial biomass C (MBC), and water-soluble organic C (WOC) by 23.1–24.7, 138.6–159.7 and 56.2–69.5% (P