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Forest Ecosystems 2021年第4期8卷 765-777页

作者： Shuo Zhang Qi Deng Ying-Ping Wang Ji Chen Mengxiao Yu Xi Fang Hongbo He Jinlei Chen Pingping Xu Shenhua Wang Junhua Yan Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems South China Botanical GardenChinese Academy of Sciences510650 GuangzhouChina University of Chinese Academy of Sciences 100049 BeijingChina Department of Agroecology Aarhus University8830 TjeleDenmark CSIRO Oceans and Atmosphere PMB 1Victoria 3195 AspendaleAustralia Aarhus University Centre for Circular Bioeconomy Aarhus University8830 TjeleDenmark iCLIMATE Interdisciplinary Centre for Climate Change Aarhus University4000 RoskildeDenmark Faculty of Life Science and Technology Central South University of Forestry and Technology410004 ChangshaChina Institute of Applied Ecology Chinese Academy of Sciences110016 ShenyangChina

Background:Forest restoration has been considered an effective method to increase soil organic carbon(SOC),whereas it remains unclear whether long-term forest restoration will continuously increase *** large uncertainties may be mainly due to the limited knowledge on how soil microorganisms will contribute to SOC accumulation over ***:We simultaneously documented SOC,total phospholipid fatty acids(PLFAs),and amino sugars(AS)content across a forest restoration gradient with average stand ages of 14,49,70,and>90 years in southern ***:The SOC and AS continuously increased with stand *** ratio of fungal PLFAs to bacterial PLFAs showed no change with stand age,while the ratio of fungal AS to bacterial AS significantly *** total microbial residue-carbon(AS-C)accounted for 0.95-1.66% in SOC across all forest restoration stages,with significantly higher in fungal residue-C(0.68-1.19%)than bacterial residue-C(0.05-0.11%).Furthermore,the contribution of total AS-C to SOC was positively correlated with clay content at 0-10 cm soil layer but negatively related to clay content at 10-20 cm soil ***:These findings highlight the significant contribution of AS-C to SOC accumulation along forest restoration stages,with divergent contributions from fungal residues and bacterial *** clay content with stand age significantly affects the divergent contributions of AS-C to SOC at two different soil layers.

关键词： soil carbon stock Microbial biomass Microbial residues Forest restoration soil clay content soil layer

Degradation of soil Properties due to Erosion on Sloping Land in Southern Jiangsu Province,China

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Pedosphere 2004年第1期14卷 17-26页

作者： ZHANGYan PENGBu-Zhuo GAOXiang YANGHao LMCP InstituteofSoilScienceChineseAcademyofSciencesNanjing210008（China） DepartmentofUrbanandResourcesScience NanjingUniversityNanjing210093（China）

soil erosion accelerates soil degradation. Some natural soils and cultivated soils on sloping land in southern Jiangsu Province, China were chosen to study soil degradation associated with erosion. soil erosion intensity was investigated using the 137Cs tracer method. soil particle-size distribution, soil organic matter (OM), total nitrogen (TN) and total phosphorus (TP) were measured, and the effects of erosion on soil physical and chemical properties were analyzed statistically using SYSTAT8.0. Results indicated that erosion intensity of cultivated soils was greater than that of the natural soils, suggesting that cultivation increased soil loss. Erosion also led to an increase of coarser soil particle proportion, especially in natural soils. In addition, silt was the primary soil particle lost due to erosion. However, in cultivated fields, coarser soil particles over time were attributed not only to soil erosion but also to mechanical eluviation as a result of farming activities. Moreover, erosion caused a decrease in soil OM, TN and TP as well as thinning of the soil layer.

关键词： ^(137)Cs coarser soils nutrients soil degradation soil layer

Critical Range of soil Boron for Prognosis of Boron Deficiency in Oilseed Rape

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Pedosphere 2001年第3期11卷 283-288页

作者： WEI YOUZHANG Department of soil Science and Agricultural Chemistry, Zhejiang University, Hangzhou 310029 (China) 浙江大学浙江杭州 310029

Relationships between seed yields of oilseed rape (Brassica napus L.) and extractable boron concentrations in three soil layers (A, P and W) were investigated through ten experiments on three types of soils (Alluvic Entisols, Udic Ferrisols and Stagnic Anthrosols) in northern, western and middle Zhejiang Province. Among several mathematical models used to described the relationships, the polynomial equation, y = a + bx + cx2 + dx3, where y is the yield of oilseed rape seed and x the extractable boron concentration in P layer of soil, was the best one. The critical range of the concentrations corresponding to 90% of the maximum oilseed rape yield was 0.40-0.52 mg kg-1. The extractable boron concentration of the P layers of the soils was the most stable. The critical range determined was verified through the production practices of oilseed rape in Zhejiang and Anhui provinces.

关键词： boron deficiency critical range oilseed rape soil layer

soil ecological stoichiometry in varied microtopographies of an alluvial fan at eastern Helan Mountains,Northwest China

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Journal of Arid Land 2024年第12期16卷 1648-1663页

作者： SHEN Aihong ZHAO Na SHI Yun MI Wenbao SHE Jie ZHANG Fenghong GUO Rui WU Tao LI Zhigang LI Jianhua ZHU Xiaowen LI Hongxia YUE Shaoli College of Forestry and Prataculture of Ningxia University Yinchuan 750021China School of Geography and Planning of Ningxia University Yinchuan 750021China Yinchuan Yinxi Ecological Protection Forest Management Center Yinchuan 750002China Helan Mountain National Nature Reserve Administration of Ningxia Yinchuan 750021China Ningxia Hui Autonomous Region Agricultural Comprehensive Development Center Yinchuan 750002China

Alluvial fans possess diverse geomorphological features and have a significant impact on soil characteristics and variations in ecological ***,it remains unclear how alluvial fans in arid mountainous areas influence the changes in ecological chemical stoichiometry and,consequently,indirectly affect ecosystem *** fan,with its diverse topographical features,exerts a multifaceted influence on soil formation and *** information exists regarding the ecological stoichiometric characteristics of the alluvial fan in arid mountainous *** study investigated the soil physical-chemical characteristics,enzyme activities,soil ecological stoichiometries,and its driving factors of four types of micro-topographies(alluvial mesas,high floodplain,groove beach,and striated groove)in the foothills of eastern Helan Mountains,*** showed that soil physical and chemical properties in the 0–20 cm soil depth was consistently higher than those in the 20–40 cm soil depth,with no changes in pH,total nitrogen,and total potassium.C:P and N:P ratios in alluvial mesas,high floodplain,and striated groove were significantly higher than those in groove *** analysis showed that soil nutrients played the most significant role in the variation of soil ecological stoichiometry *** influenced soil stoichiometry indirectly,primarily through impacts on enzyme activity and soil nutrient *** findings elucidate the intricate interplay between soil ecological stoichiometric characteristics and environmental factors across diverse micro-topographies in alluvial fan,contributing to our understanding of the formation and development of soil in dryland.

关键词： enzyme activity soil layer topography soil physical-chemical property dryland

Simulation experiment of AE-based localization damage and deformation characteristic on covering rock in mined-out area

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International Journal of Minerals,Metallurgy and Materials 2009年第3期16卷 255-260页

作者： Sheng-jun Miao Xing-ping Lai Xing-guang Zhao Fen-hua Ren School of Civil ＆ Environmental Engineering University of Science and Technology Beijing Beijing 100083 China School of Energy Engineering Xi＇an University of Science and Technology Xi＇an 710054 China

The localization damage and deformation characteristics of multiple rock in mined-out area under thick soil layer were investigated by acoustic emission （AE）-based physical similar simulation experiment and damage test combined with the AE theory on rock damage. During different mining courses, the degree of wall rock suffered from mining disturbed process in mined-out area was different, so did the AE density of initial damage and fracture. Some characteristic parameters, including large events, total events, and energy rate, presented fluctuations with temporal and spatial change and take on a certain extent statistic relation. Subsequently, the percent of damage degree was defined and divided into 4 stages, and the localization damage and deformation characteristics of surrounding rock in mined-out area and coal pillars were analyzed quantitatively.

关键词： acoustic emission soil layer underground mine rock damage in-site monitoring

soil bacterial characteristics between surface and subsurface soils along a precipitation gradient in the Alxa Desert, China

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Journal of Arid Land 2021年第3期13卷 257-273页

作者： TENG Zeyu XIAO Shengchun CHEN Xiaohong HAN Chao Key Laboratory of Ecohydrology of Inland River Basin Northwest Institute of Eco-Environmental ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

Bacteria in desert soil have unique phylogeny and important ecological functions, and theirresponses to changes in precipitation need further attention. However, relevant studies have mainlyfocused on the surface soil, and studies on the responses of bacteria at different soil depths to variationsin precipitation are rare. Thus, we used 16S rDNA high-throughput sequencing to investigate the changesin soil bacterial distribution along a mean annual precipitation gradient (50–150 mm) in the Alxa Desert,China, and compared the variation characteristics in the surface soil layer (0–10 cm) and subsurface soillayer (10–20 cm). Results showed that soil bacterial communities significantly changed along theprecipitation gradient in both soil layers. However, the subsurface soil layer could support bacterialcommunities with higher diversity and closer internal relationships but more internal competition than thesurface soil layer. Additionally, compared with the surface soil layer, variations in diversity andco-occurrence patterns in the subsurface soil layer were more in line with the changes in the mean annualprecipitation, while bacterial community structure was less variable in the subsurface soil layer. Comparedwith the mean annual precipitation, soil moisture had little influence on the structure and diversity of soilbacterial community but had a high correlation with intercommunity connectivity. Therefore, soilmoisture might play a complex role in mediating environmental conditions and soil bacterial communitycharacteristics. Due to the different responses of surface and subsurface soil bacteria to the changes inprecipitation, it is necessary to distinguish different soil layers when predicting the trends in desert soilbacterial conditions associated with precipitation, and prediction of subsurface soil bacteria may be moreaccurate.

关键词： precipitation gradient soil layer soil bacterial community structure diversity co-occurrence pattern

Recovery of Collembola in Pinus tabulaeformis Plantations

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Pedosphere 2017年第1期27卷 129-137页

作者： CHANG Liang WANG Baifeng LIU Xianghui Mac A.CALLAHAM Jr. GE Feng State Key Laboratory of Integrated Management of Pest and Rodents Institute of ZoologyChinese Academy of Sciences Northeast Institute of Geography and Agroecology Chinese Academy of Sciences USDA Forest ServiceSouthern Research StationCenter for Forest Disturbance Science

Large areas of forest plantations have been developed in China. It is important to evaluate the soil fauna in plantations and the conditions needed for their recovery in view of the large areas of plantations in China. Three Pinus tabulaeformis forests, a 26-year-old plantation （P26） and a 45-year-old plantation （P45）, exposed to clear-cutting before plantation, and an 80 260-year-old natural forest （N260）, were chosen to study the effects of different forest ages/types on Collembola community in the lifter and soil layers during 2008 and 2009. soil conditions in P26 and P45 were significantly deteriorated when compared to N260. A higher value of soil bulk density and lower values of soil organic matter, soil N, litter depth, soil pH, and soil water content were observed in P26 and P45. Totally, the same genera of Collembola tended to occur in the forests of all ages studied; however, the Collembola community structure was significantly impacted by the differences in forest age. Both in the litter and soil layers, the density and generic richness of the Collembola were the highest in N260 and the lowest in P26. Some collembolan groups were sensitive to soil conditions in particular forest ages. N260 was associated with relatively high abundance of Plutomus collembolans and P45 with relatively high abundance of Pseudofolsomia collembolans. The canonical correspondence analysis showed that the community structure of Collembola was mainly affected by forest age in both litter and soil layer. The ordination analysis of non-metric multidimensional scaling also found that the Collembola community did not recover to the level of natural forests in 26-year regeneration after clear-cutting. Even in 45-year regeneration after clear-cutting, the Collembola community only showed a slight recovery to the level of natural forests. Our results clearly showed that both Collembola community and soil conditions did not recover in 26- and 45-year regeneration after clear-cutting in P.

关键词： community structure forest age litter layer soil conditions soil fauna soil layer

Stres-disipative heat geotemperature precursor mechanism of earthquakes

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Acta Seismologica Sinica(English Edition) 1998年第5期11卷 97-103页

作者：王庆良王文萍梁伟锋陈兵

It is a common phenomenon that there exists shallow geotemperature rise precursor around an earthquake region before the event occurs. The existing models on geotemperature precursor mechanism such as the deep thermal ascent model and the model of hothouse effect, all encounter some contradictions although there is a certain evidence supporting them. From the angle of dissipative heat in the present paper, we set forth a new interpretation model named the stress-dissipative heat model with the main points of view as: the dissipative heat transformed from the work of crustal stress to non-elastic deformation of rock and soil, is one important reason for preseismic geotemperature rise. The medium-term regional and tendency geotemperature rise before an earthquake closely relates to the intensification of regional crustal stress field; the short-term and prequake geotemperature bursting rise around an earthquake region closely relates to rapid change of the source stress field. Plastic deformation and dissipative heat is much easier created in soil than rock. Therefore, the pre-earthquake geotemperature precursors mainly appear in soil covered area and mostly concentrate in shallow soil layers.

关键词： stress dissipative heat geotemperature precursor soil layer