Abstract:The stability of Earth's critical zone is intimately linked with erosion, chemical weathering and the vegetation type and density, therefore affecting the global biogeochemical processes and in turn the global climate. However, there is a lack of knowledge on how Earth's critical zone processes have changed over time. Here we rebuild erosion-weathering-vegetation interactions since ~14.7 ka using geochemical records of a radiocarbon-dated sediment core from Gonghai Lake in North China. Our results revealed distinct, millennial, late deglacial-Holocene erosion and weathering patterns and transitions. Chemical Index of Alteration (CIA) molar, a humidity proxy, indicated low humidity during the late deglacial ~11.5-14.7 ka, high humidity during the early-mid Holocene ~11.5-3.2 ka, and intermediate humidity during the late Holocene interval since ~3.2 ka. Comparison of our records with other climate reconstructions further suggested an orbital-phased humidity changes in North China. This study provides evidence for the solar-forcing controlled Earth's surface processes in the mid-latitude China under natural climate conditions.

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	1. Insolation-driven monsoon-mediated changes in Earth's surface processes in mid-latitude East Asia since the last deglaciation
	LIU Jianbao,CHEN Qiaomei,XIE Chengling
	Earth Science 05 May 2016
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	Abstract:The stability of Earth's critical zone is intimately linked with erosion, chemical weathering and the vegetation type and density, therefore affecting the global biogeochemical processes and in turn the global climate. However, there is a lack of knowledge on how Earth's critical zone processes have changed over time. Here we rebuild erosion-weathering-vegetation interactions since ~14.7 ka using geochemical records of a radiocarbon-dated sediment core from Gonghai Lake in North China. Our results revealed distinct, millennial, late deglacial-Holocene erosion and weathering patterns and transitions. Chemical Index of Alteration (CIA) molar, a humidity proxy, indicated low humidity during the late deglacial ~11.5-14.7 ka, high humidity during the early-mid Holocene ~11.5-3.2 ka, and intermediate humidity during the late Holocene interval since ~3.2 ka. Comparison of our records with other climate reconstructions further suggested an orbital-phased humidity changes in North China. This study provides evidence for the solar-forcing controlled Earth's surface processes in the mid-latitude China under natural climate conditions.
	TO cite this article:LIU Jianbao,CHEN Qiaomei,XIE Chengling. Insolation-driven monsoon-mediated changes in Earth's surface processes in mid-latitude East Asia since the last deglaciation[OL].[ 5 May 2016] http://en.paper.edu.cn/en_releasepaper/content/4686394


	2. Effect of Forest Gaps on the Photosynthetic Physiology of Castanopsis kawakamii seedlings
	TANG Rong,HE Zhongsheng,LIU Jinfu,SU Songjin,ZHENG Shiqun,HONG Wei
	Earth Science 10 April 2015
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	Abstract:The variations of photosynthetic physiology in plants were the dominant factors that could affected seedlings' dynamic growth. The objective of this study was to explore the effects of weak light on photosynthetic physiology of C.kawakamii seedlings by the measurements of chlorophyll contents, net photosynthetic rate (Pn), and chlorophyll fluorescence in forest gaps and non-gaps. The results showed that: (1) the contents of chlorophyll a (Chl-a), chlorophyll b (Chl-b), and total chlorophyll (total Chl) of C.kawakamii seedlings in forest gaps were lower than those of non-gaps while the value of chlorophyll a/b (Chl-a/b) in forest gaps was higher than that of non-gaps. The increase of Chl-b content improved the absorption of light energy which could conducive to enhance the adaptability of seedlings in non-gaps under the weak light condition, (2) the Pn of C.kawakamii seedlings in forest gaps was higher than those of non-gaps, which showed that the formation of forest gaps could improve seedlings' photosynthetic capacity and promote their growth, and (3) under the weak light condition, the initial fluorescence (Fo) of C. kawakamii seedlings in the low age classes of forest gaps and the high age classes in non-gaps showed an increasing trend. Weak light restrained the seedlings' photochemical efficiency with a downward trend in PSII photochemical conversion efficiency (Fv/Fm) for the low age classes of forest gaps. Photochemical quenching (qP) of C.kawakamii seedlings in forest gaps and non-gaps were sensitive to weak light and demonstrated a decreasing trend. The descending trend of Non-photochemical quenching coefficient (NPQ) for C.kawakamii seedlings in forest gaps was larger than that of non-gaps, which indicated that the decline of heat dissipation capacity constrained the growth of seedlings in forest gaps under the weak light condition. Seedlings in forest gaps could maintain a rapid photosynthetic electron transport rate under the weak light condition. This is due to the actual quantum yield of PSII photochemical (Y) showed a tiny decreasing trend in forest gaps than those of non-gaps. We concluded that weak light condition limited the growth of C.kawakamii seedlings at the low age classes of forest gaps and the high age classes of non-gaps.
	TO cite this article:TANG Rong,HE Zhongsheng,LIU Jinfu, et al. Effect of Forest Gaps on the Photosynthetic Physiology of Castanopsis kawakamii seedlings[OL].[10 April 2015] http://en.paper.edu.cn/en_releasepaper/content/4637682

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	3. Methane emissions from mud volcanoes in the Southern Junggar Basin, China
	Wan Zhifeng
	Earth Science 30 July 2014
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	Abstract:Methane emissions from geological sources have recently been recognised as an important component of the atmospheric methane budget. Mud volcano eruptions are an important source of methane gas emissions. A mud volcano is a geological structure formed as a result of the emission of argillaceous material on the Earth's surface or sea floor. Mud volcanoes are widely distributed, and their methane emissions are enormous. Increasing methane emissions from mud volcanoes would mean a significant increase in natural carbon emissions worldwide, with a corresponding significant effect on the worldwide environment. The annual methane emission of a single mud volcano in the southern margin of Junggar Basin, northwestern China, equals up to 666.20 m3. Additionally, the estimated annual methane emissions might be up to 3.33 × 107 m3 in the study area, which measures 200 × 100 m2. Thus, more attention should be focused on the methane emitted from mud volcanoes.
	TO cite this article:Wan Zhifeng. Methane emissions from mud volcanoes in the Southern Junggar Basin, China[OL].[30 July 2014] http://en.paper.edu.cn/en_releasepaper/content/4605218


	4. A fast automatic interpretation of 3D potential-field data
	ZhangXu,YuPeng,ChenXiao,Tang Rui,XiangYang
	Earth Science 07 November 2013
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	Abstract:Gravity and magnetic data have been extensively used in the interpretation of geologic features, such as location, depth and geological structures. We have presented two improved technique for inversing the source parameters. First we introduce a new filter called sine angle, which is useful to improve the resolution of the weak response of deep-source. We also develop a simple approach to determine both the depth and source geometry. We have generalized the approach for gravity field, especially for contact of the gravity and multiple sources with different geometries. The feasibility and stability of our method are demonstrated on synthetic data.
	TO cite this article:ZhangXu,YuPeng,ChenXiao, et al. A fast automatic interpretation of 3D potential-field data[OL].[ 7 November 2013] http://en.paper.edu.cn/en_releasepaper/content/4568602


	5. Major Element Characteristics of the Reticulate Laterites and their Indicative Weathering Intensity in Northeastern Guangdong Province, China during the Late Pleistocene
	Wen Xiaohao
	Earth Science 01 March 2013
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	Abstract:Reticulate laterites have been well-developed on the top regolith materials of South China. Two typical profiles, Linjiang and Jiaoling, are selected and their ages and major elements are determined. The data from three thermoluminescence (TL) and three optically stimulated luminescence datas reveal that both reticulate laterites of Linjiang and Jiaoling profiles correspond well with the late quaternary, especially the last interglacial. The geochemical data show that strong-weathered reticulate laterites are mainly composed of SiO2, Al2O3 and TFe, which tend to be easily assembled under warm and wet conditions, and the distributing limits are 60.32 to 67.81%, 17.52 to 21.32% and 4.17 to 5.96% in Linjiang and 50.10% to 53.14%,23.07% to 24.44%,10.18% to 11.40%, in respect. The other major elements such as Na2O, CaO, MgO, which tend to be easily eluviated under warm and wet conditions, and their distributing limits were all below 0.50%, showing being violently eluviated. These geochemical characteristics (such as major elements' distributings, weathering eigenvalues and CIA values) indicated both reticulate laterites of Linjiang and Jiaoling profiles have undergone the intensive weathering of biochemistry under the tropical-subtropical wetter and warmer climate-environment, which apparently reflects the climate was rather wetter and warmer during late quaternary, especially the last interglacial in Northeastern Guangdong province.
	TO cite this article:Wen Xiaohao. Major Element Characteristics of the Reticulate Laterites and their Indicative Weathering Intensity in Northeastern Guangdong Province, China during the Late Pleistocene[OL].[ 1 March 2013] http://en.paper.edu.cn/en_releasepaper/content/4523823


	6. Driving forces of species extinction in framentated habitat
	Liu Huiyu
	Earth Science 15 January 2013
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	Abstract:In this paper, Habitat fragmentation can reduce not only species abundance, but also effective colonization ability, and further change the interpecific competition. Habitat fragmentation is one of the leading causes of species extinction. However, extinction may come from habitat destruction or competition, which is not revealed explicitly. In this paper, we simulated the species extinction response to spatial-temporal heterogeneity by cellular automata, and further study the effects of habitat destruction and interspecific competition. The results show that: 1) the extinction of superior competitor comes from habitat destruction. 2) the extinction of inferior competitor comes from habitat destruction and competition under random destruction, while comes from competition under edge destruction; 3) extinction time resulting from both habitat destruction and competition is very short, reversely, extinction time solely from habitat destruction or competition is very long.
	TO cite this article:Liu Huiyu. Driving forces of species extinction in framentated habitat[OL].[15 January 2013] http://en.paper.edu.cn/en_releasepaper/content/4513524


	7. Microwave Doppler spectra of sea echoes at high incidence angles: Influence of larger-scale waves
	Wang Yunhua
	Earth Science 02 December 2011
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	Abstract:Within the framework of the composite surface scattering model, analytical formulas for Doppler shift and bandwidth of radar echoes backscattered from time-varying sea surface are derived in the forms of three-dimensional integrals. In our derivations, the influences of the tilt modulation, the hydrodynamic modulation, the shadow and the curvature of large-scale undulating waves are all taken into account for achieving more reasonable results. Comparisons between our theoretical curves with the results obtained directly by exact numerical method demonstrate that our formulas can improve the simulated results. On the other hand, the simulations by our formulas can also help to estimate the effects of the tilt modulation, the hydrodynamic modulation, and the shadow of large-scale waves on Doppler behaviors individually. We find that the predicted Doppler shifts are always larger in HH-polarization than in VV-polarization due to the tilt modulation. Meanwhile, the simulations also show that the predicted Doppler shifts for both HH- and VV- polarizations would become larger when the hydrodynamic modulation is considered. In addition, at low-grazing angles (LGA), the shadow of large-scale undulating waves results in a rapid increase in the predicted Doppler shift, and on the contrary the shadow makes the bandwidth becoming narrower.
	TO cite this article:Wang Yunhua. Microwave Doppler spectra of sea echoes at high incidence angles: Influence of larger-scale waves[OL].[ 2 December 2011] http://en.paper.edu.cn/en_releasepaper/content/4453378


	8. Shrinkage and cracking behaviour of swelling soil under different temperatures
	TANG Chaosheng
	Earth Science 06 January 2011
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	Abstract:In this investigation, desiccation tests were conducted on two swelling soil slurries (Xiashu clay and Romainville clay) under different environmental temperature conditions. During drying, the water loss rate, volume shrinkage, initiation and propagation of desiccation cracks were monitored. By applying computer image processing technology, the geometric parameters of the crack pattern and the corresponding probability density functions (PDF) were determined. In addition, the surface crack ratio Rsc was introduced to quantify crack networks at different water contents. The results show that the soil water evaporation process is composed of two stages: a constant rate zone and a subsequent falling rate zone; higher water loss rate is accompanied by higher temperature; the cracking water content, crack length, width, aggregate area and their probability density functions increase with an increase of temperature; the Rsc increases evidently with a decrease of water content, and gradually tents to stabilization once the shrinkage limit (SL) is reached. The increase of Rsc is accompanied by the decrease of void ratio, and the cracking curve (Rsc versus water content) to some extent reflects the shrinkage properties of soil. During drying, most of the cracks developed before the air entry (AE) point where the soil specimen is still saturated.
	TO cite this article:TANG Chaosheng. Shrinkage and cracking behaviour of swelling soil under different temperatures[OL].[ 6 January 2011] http://en.paper.edu.cn/en_releasepaper/content/4404675


	9. Variation of the Moisture Index from March to August during Recent 100 Years Indicated by Tree Ring of Luoshan Mountains
	Wang Yajun,Ma Yuzhen,Lu Ruijie,Sang Yanli,Meng Hongwei
	Earth Science 06 January 2011
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	Abstract:The tree-ring width of Pinus Tabulaeformis from Luoshan Mountains correlates positively with the monthly precipitation and negatively with the monthly temperature during the growing season. There is a more significant relation between tree-ring width and the moisture index (P/T): the simultaneous influence of precipitation and temperature. The reconstructed equation of the moisture index from March to August is developed using the tree-ring width, with a correlation coefficient of 0.621, and reaches 0.001 significent level. The reconstructed moisture index shows that there is a markable change of humid and dryness during recent 100 years, The reconstructed moisture index lower than average reflects the drought years recorded in historical documents; By constrasting with other areas, the dry period from 1923 to 1931 is correspondent with the period of high temperature and low precipitation during the 1920s' and 1930s' at Northwest, North China and Yangtze River Basin in China. Moreover, the humid period from 1939 to 1944 corresponds well with those of Qilianshan Mountains, the south Plateau of Qinghai and the East Tianshan Mountains, etc, and also with the period of low temperature and high precipitation after 1940s' at Northwest, North China and Yangtze River Basin in China. After primary analysis we conclude that the moisture index within 100 years of Luoshan records the dry and wet change of Northwest at least and may be close with the climatic change in large range.
	TO cite this article:Wang Yajun,Ma Yuzhen,Lu Ruijie, et al. Variation of the Moisture Index from March to August during Recent 100 Years Indicated by Tree Ring of Luoshan Mountains[OL].[ 6 January 2011] http://en.paper.edu.cn/en_releasepaper/content/4404537


	10. Numericle simulation of the formation of linear dunes
	Zhang Ruyan,Luo Chunmei
	Earth Science 17 October 2010
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	Abstract:Three-dimensional flow above the sand dunes have been studied numerically by using Large-Eddy Simulation (LES) method. In the flow direction and span direction cyclic boundary conditions are imposed for velocity and pressure. The movement of the sand which is known as the elemental types of desert have been investigated. The numerical method employed in this study can be divided into three parts: (i) calculation of the air flow above the sand dunes using standard MAC method with a generalized coordinate system; (ii) estimation of the sand transfer caused by the flow through the friction; (iii) determination of the shape of the ground. Since the computational area has been changed due to step (iii), steps (i)-(iii) are repeated until prescribed times. The simulated dunes, which is formed by two directional winds, extends at the converging direction which is known as linear dunes.
	TO cite this article:Zhang Ruyan,Luo Chunmei. Numericle simulation of the formation of linear dunes[OL].[17 October 2010] http://en.paper.edu.cn/en_releasepaper/content/4387969

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