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Acidity and conductivity of Pinus massoniana bark as indicators to atmospheric acid deposition in Guangdong, China

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Journal of Environmental Sciences 2006年第5期18卷 916-920页

作者： KUANG Yuan-wen zhou guo-yi WEN Da-zhi LIU Shi-zhong Institute of Ecology South China Botanical Garden＇ Chinese Academy of Sciences Guangzhou 510650 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

Barks of Pinus massoniana collected from two polluted sites, Qujiang and Xiqiaoshan, and from the relatively clean site Dinghushan were used to evaluate the pollution indication by the determination of their acidity and conductivity. The acidity of the inner and outer barks from the polluted sites was significantly higher than those from the clean site, suggesting that the acidity of the bark occurred in concurrent with the air pollution. The significant lower pH values of the outer bark than the inner bark collected from all sites indicated that the outer bark was more sensitive than the inner bark in response to acid pollution, implying that the outer bark is more preferable when used as indication of atmospheric acid pollution. The conductivities of the inner barks differed significantly among the three sites, with higher values at the clean site. However, the significant differences were not observed among these sites. Furthermore, the pH values for the inner and outer barks were not correlated with the conductivity, which did not coincide with some other studies.

关键词： acidity conductivity inner bark outer bark Pinus massoniana

Changes of Soil Water, Organic Matter, and Exchangeable Cations Along a Forest Successional Gradient in Southern China

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Pedosphere 2007年第3期17卷 397-405页

作者： YAN Jun-Hua zhou guo-yi ZHANG De-Qiang CHU guo-Wei South China Institute of Botany Chinese Academy of Sciences Guangzhou 510650 （China）

Information on the distribution patterns of soil water content （SWC）, soil organic matter （SOM）, and soil exchangeable cations （SEC） is important for managing forest ecosystems in a sustainable manner. This study investigated how SWC, SOM, and SEC were influenced in forests along a successional gradient, including a regional climax （monsoon evergreen broad-leaved forest, or MEBF）, a transitional forest （coniferous and broad-leaved mixed forest, or MF）, and a pioneer forest （coniferous Masson pine （Pinus rnassoniana） forest, or MPF） of the Dinghushan Biosphere Reserve in the subtropical region of southern China. SWC, SOM, and SEC excluding Ca^2＋ were found to increase in the soil during forest succession, being highest in the top soil layer （0 to 15 cm depth） except for Na^＋. The differences between soil layers were largest in MF. This finding also suggested that the nutrients were enriched in the topsoil when they became increasingly scarce in the soil. There were no significant differences （P = 0.05） among SWC, SOM, and SEC. A linear, positive correlation was found between SWC and SOM. The correlation between SOM and cation exchange capacity （CEC） was statistically significant, which agreed with the theory that the most important factor determining SEC is SOM. The ratio of K^＋ to Na^＋ in the topsoil was about a half of that in the plants of each forest. MF had the lowest exchangeable Ca^2＋ concentration among the three forests and Ca^2＋：K^＋ in MPF was two times higher than that in MF. Understanding the changes of SWC, SOM, and CEC during forest succession would be of great help in protecting all three forests in southern China.

关键词： forest succession soil exchangeable cations soil organic matter soil water content

Dynamics of soil inorganic nitrogen and their responses to nitrogen additions in three subtropical forests, south China

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Journal of Environmental Sciences 2006年第4期18卷 752-759页

作者： FANG Yun-ting ZHU Wei-xing MO Jiang-ming zhou guo-yi GUNDERSEN Per Dinghushan Forest Ecosystem Research Station South China Botanical Garden Chinese Academy of Sciences Zhaoqing 526070 China Biological Sciences Binghamton University-SUNY Binghamton NY 13902-6000 USA Forest and Landscape Denmark Hoersholm Kongevej 11 2970 Denmark The Graduate School of the Chinese Academy of Sciences Beijing 100039 China

Three forests with different historical land-use, forest age, and species assemblages in subtropical China were selected to evaluate current soil N status and investigate the responses of soil inorganic N dynamics to monthly ammonium nitrate additions. Results showed that the mature monsoon evergreen broadleaved forest that has been protected for more than 400 years exhibited an advanced soil N status than the pine （Pinus massoniana） and pine-broadleaf mixed forests, both originated from the 1930＇s clear-cut and pine plantation. Mature forests had greater extractable inorganic N pool, lower N retention capacity, higher inorganic N leaching, and higher soil C/N ratios. Mineral soil extractable NH4^＋-N and NO3-N concentrations were significantly increased by experimental N additions on several sampling dates, but repeated ANOVA showed that the effect was not significant over the whole year except NH4^＋-N in the mature forest. In contrast, inorganic N （both NH4^＋-N and NO3^--N） in soil 20-cm below the surface was significantly elevated by the N additions. From 42% to 74% of N added was retained by the upper 20 cm soils in the pine and mixed forests, while 0%-70% was retained in the mature forest. Our results suggest that land-use history, forest age and species composition were likely to be some of the important factors that determine differing forest N retention responses to elevated N deposition in the study region.

关键词： N deposition N saturation extractable inorganic N soil solution inorganic N subtropical China

Preliminary Response of Soil Fauna to Simulated N Deposition in Three Typical Subtropical Forests

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Pedosphere 2006年第5期16卷 596-601页

作者： XU guo-Liang MO Jiang-Ming zhou guo-yi FU Sheng-Lei Institute of Ecology South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 （China） Graduate School of the Chinese Academy of Sciences Beijing 100039 （China）

A field-scale experiment arranged in a complete randomized block design with three N addition treatments including a control (no addition of N), a low N (5 g m-2 year-1), and a medium N (10 g m-2 year-1) was performed in each of the three typical forests, a pine (Pinus massoniana Lamb.) forest (PF), a pine-broadleaf mixed forest (MF) and a mature monsoon evergreen broadleaf forest (MEBF), of the Dinghushan Biosphere Reserve in subtropical China to study the response of soil fauna community to additions of N. Higher NH4+ and NO3- concentrations and a lower soil pH occurred in the medium N treatment of MEBF, whereas the NO3- concentration was the lowest in PF after the additions of N. The response of the density, group abundance and diversity index of soil fauna to addition of N varied with the forest type, and all these variables decreased with increasing N under MEBF but the trend was opposite under PF. The N treatments had no significant effects on these variables under MF. Compared with the control plots, the medium N treatment had significant negative effect on soil fauna under MEBF. The group abundance of soil fauna increased significantly with additions of higher N rates under PF. These results suggested that the response of soil fauna to N deposition varied with the forest type and N deposition rate, and soil N status is one of the important factors affecting the response of soil fauna to N deposition.

关键词： Dinghushan Biosphere Reserve N deposition soil fauna subtropical China

Response of Nitrogen Leaching to Nitrogen Deposition in Disturbed and Mature Forests of Southern China

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Pedosphere 2009年第1期19卷 111-120页

作者： FANG Yun-Ting M. YOH MO Jiang-Ming P. GUNDERSEN zhou guo-yi Dinghushan Forest Ecosystem Research Station South China Botanical Garden the Chinese Academy of Sciences Zhaoqing Guangdong 520670 （China） Tokyo University of Agriculture and Technology Tokyo 183-8509 （Japan） Forest ＆ Landscape Denmark Faculty of Life Sciences University of Copenhagen Hoersholm Kongevej 112970 （Denmark）

Current nitrogen (N) leaching losses and their responses to monthly N additions were investigated under a disturbed pine (Pinus massoniana) forest and a mature monsoon broadleaf forest in southern China. N leaching losses from both disturbed and mature forests were quite high (14.6 and 29.2 kg N ha-1 year-1, respectively), accounting for 57% and 80% of their corresponding atmospheric N inputs. N leaching losses were substantially increased following the first 1.5 years of N applications in both forests. The average increases induced by the addition of 50 and 100 kg N ha-1 year-1 were 36.5 and 24.9 kg N ha-1 year-1, respectively, in the mature forest, accounting for 73.0% and 24.9% of the annual amount of N added, and 14.2 and 16.8 kg N ha-1 year-1 in the disturbed forest, accounting for 28.4% and 16.8% of the added N. Great N leaching and a fast N leaching response to N additions in the mature forest might result from long-term N accumulation and high ambient N deposition load (greater than 30 kg N ha-1 year-1 over the past 15 years), whereas in the disturbed forest, it might result from the human disturbance and high ambient N deposition load. These results suggest that both disturbed and mature forests in the study region may be sensitive to increasing N deposition.

关键词： atmospheric N deposition N addition N leaching loss N saturation subtropical forests

Raman Spectroscopic Analysis of the Effect of Ultraviolet Irradiation on Calf Thymus DNA

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Acta Biochimica et Biophysica Sinica 2005年第1期37卷 39-46页

作者： Yu-Long TANG zhou-yi guo~* Institute of Laser and Life Science.South China Normal University,Guangzhou 510631,China Institute of Laser and Life Science South China Normal UniversityGuangzhou 510631 China

Raman spectroscopy was used for the first time to detect the effect of independent UVA(ultraviolet-A:320-400 nm)and UVB(ultraviolet-B:280-320 nm)irradiation on the calf thymus DNA inaqueous *** both UVA and UVB irradiation for 1 h or 3 h,the damage to the conformation of DNAwas rnoderate,but the reduction of the B-form DNA component was *** UVA and UVB causedsignificant damage to the deoxyribose moiety and bases,among which the pyrimidine base pairs were moreseriously *** appeared to be preferential damaging sites on DNA molecules caused by UVA andUVB irradiation,UVA irradiation caused more damage to the deoxyribose than UVB irradiation,while UVBirradiation caused more significant damage to the pyrimidine moiety than UVA *** UVB irradia-tion for 3 h,unstacking of the AT base pairs and the cytosine ring took place,severe damage to the thyminemoiety occurred,and some base pairs were ***,with either UVA or UVB irradiation for 3 h,the photoreactivation of DNA *** damage to the DNA caused by UVB was immediate,while thedamage caused by UVA was proportional to the irradiation *** experimental results partly indicatethe formation of some cyclobutane pyrimidine dimers and(6-4)pbotoproducts.

关键词： Raman spectroscopy deoxyribonucleic acid(DNA) ultraviolet irradiation(UV) base pair

Effect of Simulated Acid Rain on Potential Carbon and Nitrogen Mineralization in Forest Soils

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Pedosphere 2008年第4期18卷 503-514页

作者： OUYANG Xue-Jun zhou guo-yi HUANG Zhong-Liang LIU Ju-Xiu ZHANG De-Qiang LI Jiong South China Botanic Garden Chinese Academy of Sciences Guangzhou 510650 （China） Graduate School of the Chinese Academy of Sciences Beijing 100049 （China）

Acid rain is a serious environmental problem worldwide. In this study, a pot experiment using forest soils planted with the seedlings of four woody species was performed with weekly treatments of pH 4.40, 4.00, 3.52, and 3.05 simulated acid rain (SAR) for 42 months compared to a control of pH 5.00 lake water. The cumulative amounts of C and N mineralization in the five treated soils were determined after incubation at 25 ℃ for 65 d to examine the effects of SAR treatments. For all five treatments, cumulative CO2-C production ranged from 20.24 to 27.81 mg kg-1 dry soil, net production of available N from 17.37 to 48.95 mg kg-1 dry soil, and net production of NO-3 -N from 9.09 to 46.23 mg kg-1 dry soil. SAR treatments generally enhanced the emission of CO2-C from the soils; however, SAR with pH 3.05 inhibited the emission. SAR treatments decreased the net production of available N and NO3-N. The cumulative CH4 and N2O productions from the soils increased with increasing amount of simulated acid rain. The cumulative CO2-C production and the net production of available N of the soil under Acmena acuminatissima were significantly higher (P ≤ 0.05) than those under Schima superba and Cryptocarya concinna. The mineralization of soil organic C was related to the contents of soil organic C and N, but was not related to soil pH. However, the overall effect of acid rain on the storage of soil organic matter and the cycling of important nutrients depended on the amount of acid deposition and the types of forests.

关键词： forest soils mineralization organic C organic N simulated acid rain

Effect of Simulated N Deposition on Soil Exchangeable Cations in Three Forest Types of Subtropical China

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Pedosphere 2009年第2期19卷 189-198页

作者： LU Xian-Kai MO Jiang-Ming P.GUNDERSERN ZHU Wei-Xing zhou guo-yi LI De-Jun ZHANGXu Dinghushan Forest Ecosystem Research Station South China Botanical Garden Chinese Academy of Sciences Zhaoqing 526070 China Danish Centre for Forest Landscape and Planning University of Copenhagen Hoersholm Kongevej 11 DK-2970 Hoersholm Denmark Department of Biological Sciences State University of New York Binghamton NY 13902-6000 （USA） Nanjing Agricultural University Nanjing 210095 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China

The effects of simulated nitrogen(N)deposition on soil exchangeable cations were studied in three forest types of subtropical *** N treatments with three replications were designed for the monsoon evergreen broadleaf forest (mature forest):control(0 kg N ha-1 year-1),low N(50 kg N ha-1 year-1),medium N(100 kg N ha-1 year-1)and high N(150 kg N ha-1 year-1),and only three treatments(i.e.,control,low N,medium N)were established for the pine and mixed *** had been applied continuously for 26 months before the *** mature forest responded more rapidly and intensively to N additions than the pine and mixed forests,and exhibited some significant negative symptoms,e.g.,soil acidification,Al mobilization and leaching of base cations from *** pine and mixed forests responded slowly to N additions and exhibited no significant response of soil *** of soil exchangeable cations to N deposition varied in the forests of subtropical China,depending on soil N status and land-use history.

关键词： exchangeable cation forest soil land-use history N deposition subtropics

Therapeutic Role of Chinese Medicine Targeting Nrf2/HO-1 Signaling Pathway in Myocardial Ischemia/Reperfusion Injury

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Chinese Journal of Integrative Medicine 2024年第10期30卷 949-960页

作者： LIU Chang-xing guo Xin-yi zhou Ya-bin WANG He First Clinical Medical School Heilongjiang University of Chinese MedicineHarbin150040China Clinical Medical School Chengdu University of Traditional Chinese MedicineChengdu610036China Department of Cardiology the First Affiliated Hospital of Heilongjiang University of Chinese MedicineHarbin150040China

Acute myocardial infarction(AMI),characterized by high incidence and mortality rates,poses a significant public health *** therapy,though the preferred treatment for AMI,often exacerbates cardiac damage,leading to myocardial ischemia/reperfusion injury(MI/RI).Consequently,the development of strategies to reduce MI/RI is an urgent priority in cardiovascular *** medicine,recognized for its multi-component,multi-pathway,and multi-target capabilities,provides a novel approach for alleviating MI/RI.A key area of interest is the nuclear factor E2-related factor 2(Nrf2)/heme oxygenase-1(HO-1)*** pathway is instrumental in regulating inflammatory responses,oxidative stress,apoptosis,endoplasmic reticulum stress,and ferroptosis in MI/*** paper presents a comprehensive overview of the Nrf2/HO-1 signaling pathway's structure and its influence on MI/***,it reviews the latest research on leveraging Chinese medicine to modulate the Nrf2/HO-1 pathway in MI/RI treatment.

关键词： nuclear factor E2-related factor 2/heme oxygenase-1 signaling pathway myocardial ischemia/reperfusion injury Chinese medicine mechanisms