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Temperature variations recovered from tree-rings in the middle Qilian Mountain over the last millennium

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Science china Earth sciences 2005年第4期48卷 521-529页

作者： LIU Xiaohong1,2. QIN Dahe1, shao {2. , CheN Tuo1 & REN Jiawen12.1. Cold and Arid Regions Environmental and Engineering research {2., Chinese Academy of sciences, Lanzhou 73.000, china 2. {2. of geographical sciences and natural {12. research, Chinese Academy of sciences, Beijing 100101, china 1. Cold and Arid Regions Environmental and Engineering research institute Chinese Academy of Sciences 730000 Lanzhou China 2..institute of {2.{2..and natural resources research Chinese Academy of Sciences 100101 Beijing China

Based on the cross-dated tree-ring samples collected from the middle Qilian Moun- tain, a standard ring-width chronology had been developed, which covered the period AD 1000 to {3.0. The correlations between the chronology and climatic records from the nearby meteorological stations indicated that temperature was the dominant climatic factor for tree growth at upper timberline, and the most important climatic factor for the tree growth in the area was the mean temperature from previous December to current April. The temperature variations recovered from the ring-width data showed a cold period during the “Little Ice Age” and the con- tinuous warming during the twentieth century. Comparison between the ring-width chronology and δ18O records from the Dunde ice core in the Qilian Mountain indicated that there was a con- sistent trend in both time series. A significant correlation existed between our ring-width chro- nology and the Northern hemispheric temperature, suggesting that the climate changes in the Qilian Mountain were not only driven by regional factors, but also responsive to the global cli- mate.

关键词： middle Qilian Mountain, tree-ring width chronology, temperature variations.

Spatial distribution of surface rock fragment on hillslopes in a small catchment in wind-water erosion crisscross region of the Loess Plateau

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Science china Earth sciences 2008年第6期51卷 862-870页

作者： ZHU YuanJun1,2.. shao MingAn1 1 {2. of Soil and Water Conservation, Chinese Academy of {2..and Ministry of Water {2., Northwest Agriculture and Forestry University, Yangling 712..0, china 2..1} of geographical {2..and natural {2. {12., Chinese Academy of {2.. Beijing {12.. china 1. institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources Northwest Agriculture and Forestry University Yangling 712100 China 2..institute of {2.{2..and natural resources research Chinese Academy of Sciences Beijing 100101 China

The cover and size distributions of surface rock fragment in hillslopes were investigated by using digital photographing and treating technique in a small catchment in wind-water erosion crisscross region of the Loess Plateau. The results indicated that the maximal cover of rock fragment was pre-sented at mid-position in steep hillslope. Rock fragment presented a general decreasing-trend along the hillslope in gentle hillslope. Rock fragment cover was positively related to gradient, rock fragment size decreased generally along the hillslope, and the size reduced with the gradient. The mean size of rock fragment was at a range of 6―2..mm in the steep hillslope, rock fragment size > 50 mm was rarely presented. The covers of rock fragment at different positions were markedly related to the quantities of rock fragment he area of rock fragment of 2..0 mm accounted for 60% or more of the total area, dominating the distribution of rock fragment in the hillslopes.

关键词： wind-water erosion crisscross region of the Loess Plateau small catchment hillslope surface rock fragment cover and size

Water Security Problem in North china: research and Perspective

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Pedosphere 2005年第5期15卷 563-575页

作者： XIA Jun LIU Meng-Yu JIA shao-Feng Key Laboratory of Water Cycle ＆Related Land Surface Processes Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 （China） State Key Laboratory of Water resources ＆ Hydropower Engineering sciences Wuhan University Wuhan 430072（China） Center for Agricultural resources research Institute of Genetic and Developmental Biology Chinese Academy of Sciences Shijiazhuang 050021 （China）

This paper addresses the emergence of water security problems in North china with the aim of highlighting key water{3. management and water security issues for the long-term development of North china. Three key problemsrelated to water {3. and security issues in North china in the 2..t century are addressed, namely 1) the watercycle under environmental change, 2..agricultural water saving, and 3. water security. Development of international{12. related to these issues is also reviewed. The {12. plan developed recently by the Chinese Academy of sciences(CAS) is discussed and suggestions on {12. and development of water {3. science in North china are *** to focus on experimental catchments and dedicated {12. stations, a detailed knowledge of the water cycle onNorth china farmland has been compiled. A range of techniques that include isotope tracers has been used to acquirehydrologic data. Much {12. has been devoted to developing distributed hydrological models at different scales. In thewell irrigation district, five different water saving irrigation regimes have been investigated, and these regimes have hadwidespread application, and reduced water use 60-150 mm while they increased water use efficiency (WUE) by 2..-3.%.Furthermore, preventing water pollution is the most essential step to ensure North china’s water security.

关键词： environmental change North china water cycle water resources water security

Relationship between environmental evolution and human activities in the northeastern Qinghai-Xizang Plateau throughout the past millennium and its implications for the onset of the Anthropocene

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Science china Earth sciences 2024年第11期67卷 3536-3549页

作者： Yang PU Xueqiong WEI Jianbao LIU Ke ZHANG Beibei LI Zhudeng WEI Mengmeng ZHANG Tong he Yanjun WANG Xiaohua shao School of geographical sciences Nanjing University of Information Science and Technology Key Laboratory of Alpine Ecology Institute of Tibetan Plateau Research Chinese Academy of Sciences State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences

In current research on the Anthropocene, assessing the impact of human activities via stratigraphic records of sediments and demarcating the Anthropocene epoch globally are critical scientific issues that urgently need to be addressed. The northeastern Qinghai-Xizang Plateau(QXP), where humans first settled permanently in large numbers in the QXP, has varying sedimentary environments that are extremely sensitive to human activities. In contrast to other regions of the QXP, the northeastern sector boasts a richer array of climatic and environmental reconstruction sequences. This distinctive feature renders it an exemplary locale for investigating the stratigraphic boundary of the Anthropocene. Through in-depth analysis and integration of existing paleoclimate and paleoenvironment sequences in the northeastern QXP, we draw the following conclusions:(1) Throughout the past millennium, the impact of human activities on the environment of the northeastern QXP has become increasingly significant, especially in the past 2..–3.0 years, gradually overshadowing climatic factors.(2..Since AD 1950,multiple physicochemical indicators related to human activities in the northeastern QXP have shown exponential growth,forming a distinct peak within the past millennium and clearly depicting the global “Great Acceleration” phenomenon and its development process.(3. Intensified human activities have driven swift environmental shifts and “decoupled” the interplay between climatic variations and the ecological environment, propelling the northeastern QXP into the “Early Anthropocene”from the “Late Holocene”. On the basis of the above findings, we construct a model suitable for identifying the stratigraphic boundary of the Anthropocene in the northeastern QXP and note that since the ecological environment in the northeastern QXP has entered the “Early Anthropocene”, the climate signals of certain physicochemical indicators in sediments are gradually becoming weaker, whereas the signals of

关键词： Anthropocene Qinghai-Xizang Plateau (QXP) Climate change Environmental evolution Human activities

Current situation and trend of arable land change in china

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Journal of geographical sciences 2000年第3期10卷 28-34页

作者： Received date: 1999-11-02..ENG Xiang-jing1 , JIA shao-feng 2..1.{3. of Population {2.. People’s University of china, Beijing 100872..3. 2..{3. of Geographic sciences and natural resources {2.. Chinese Academy of sciences, Beiji 中国人民大学北京中科院地理科学与资源所北京

How to protect arable land in the process of economic development and urbanization is a critical issue in china. In this paper, an attempt is made to analyze the situation of arable land change in china and it's relationship with population growth, economic development and urbanization. In depth analysis is also made in different regions. Forecasting is conducted to show the trend of arable land change in china based on the results of correlation analysis. Some suggestions are put forward for the policy making of reasonable utilization and protection of arable land in the future.

关键词： arable land change population growth economic development urbanization

The Climatic Signals in Tree-ring Chronologies of Qilian Juniper and Qinghai Spruce With Reference to the Aspects in Qinghainan Mountain in Northeast Tibetan Plateau

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The Climatic Signals in Tree-ring Chronologies of Qilian Jun...

research progress of socio-economic water cycle in china

第四届青藏高原国际学术研讨会

作者： Liang Eryuan~(1,2..shao {2.~(1,2..1 {2..of {2. sciences and natural resources research, Chinese Academy of sciences, Beijing, 100101 2..2..of Tibetan Plateau research, Chinese Academy of sciences, Beijing, 100085

Qilian juniper (Sabina przewalskii Kom.) and Qinghai spruce (Picea crassifolia Kom.) are endemic and widespread species in northeast Tibetan Plateau. The existence of mixed forests of two species provides a rare opportunity to compare their growth behaviour and climate-tree growth relationships under the same environment. herein, two mixed forests at western (H1 and H2..and eastern (H3.and H4) aspects of Qinghainan Mts. (3.°2..05 98°40.007, 3.3.-3.00 m) in the east margin of Qaidam Basin were selected. H1, 3.and H2..4 are Qilian juniper and Qinghai spruce forests sites, respectively.

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Journal of geographical sciences 2002年第1期12卷 114-120页

作者： JIA shao-feng, WANG Guo, ZHANG Shi-feng, YU Gui-rui, WANG Jin-xia, XIA Jun (institute of Geographic {{2.and{3. resources research, CAS, Beijing 100101,china) institute of Geographic sciences and{{2.{3. research CAS 北京 100101

china has made great progress in the study of socio-economic water cycle. She has completed national water {3. appraisement and medium to long-term water supply planning. She has been engaging in study on water-deficient regions in North{2..and Northwest{2..for about half a century. For solving water shortage problem in northern{2.. she has put forward the famous South-to-North Water Transferring Projects, which has been set as one of the four biggest national projects in the Tenth Five-Year-Plan period although there are still debates. For promoting water use efficiency,{2..has been reforming her water management system, including water right system and water price system. There has already been a case of water right purchase.{2..has also done a lot of research on the interaction between human activity, water and ecosystem. For meeting the need of sustainability and coordinating water {3. development and environmental protection, the study of ecological water requirement became very hot in recent years. There are three focuses of socio-economic water cycle study now in{2.. water transfer projects from the south to the north, water {3. management and ecological water requirement.

关键词： water cycle socio-economic water cycle sustainable water resources management water security

Estimation of soil organic carbon reservoir in china

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Journal of geographical sciences 2001年第1期11卷 3-13页

作者： WANG shao-qiang1, ZHOU Cheng-hu1, LI Ke-rang1, ZHU Song-li{2.HUANG Fang-hong1 (1.The State Key Laboratory of resources and Environment Information System, {{2.of Geographic {2. and natural resources research, CAS, Beijing 100101, china The State Key Laboratory of resources and Environment Information System Institute of Geographic Sciences and Natural Resources Research CAS Beijing China institute of Environment Science Beijing Normal University Beijing China

The paper respectively adopted physio-chemical properties of every soil stratum from {2.3.soil profiles of the second national soil survey. The corresponding carbon content of soils is estimated by utilizing conversion coefficient 0.58. In the second soil survey, the total amount of soil organic carbon is about 9{2.18xl08t and carbon density is about 10.53.kgC/m{2.n china according to the area of 877.63.106hm{2.urveyed throughout the country. The spatial distribution characteristics of soil organic carbon in china is that the carbon storage increases when latitude increases in eastern china and the carbon storage decreases when longitude reduces in northern china. A transitional zone with great variation in carbon storage exists. Moreover, there is an increasing tendency of carbon density with decrease of latitude in western china. Soil circle is of great significance to global change, but with substantial difference in soil spatial distribution throughout the country. Because the structure of soil is inhomogeneous, it could bring some mistakes in estimating soil carbon reservoirs. It is necessary to farther resolve soil respiration and organic matter conversion and other questions by developing uniform and normal methods of measurement and sampling.

关键词： terrestrial ecosystem global change soil carbon reservoir carbon cycle

Patterns and drivers of seasonal water sources for artificial sand-fixing plants in the northeastern Mu Us sandy land,Northwest{2.

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Pedosphere 2024年第1期34卷 63-77页

作者： Yanwu PEI Laiming HUANG Ming'an shao Jiao WANG Yinglong ZHANG Yellow River Delta Modern Agricultural Engineering Laboratory Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of natural resources and Environment Northwest Agriculture and Forestry UniversityYangling 712100China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences of Chinese Academy of SciencesBeijing 100085China College of resources and Environment University of Chinese Academy of SciencesBeijing 100049China Shenmu Ecological Association Shenmu 719399China

Understanding plant water-use patterns is important for improving water-use efficiency and for sustainable vegetation restoration in arid and semi-arid regions. However, seasonal variations in water sources and their control by different sand-fixing plants in water-limited desert ecosystems remain poorly understood. In this study, stable isotopic ratios of hydrogen(δ^(2..) and oxygen(δ^(18)O) in precipitation, soil water, groundwater, and xylem water were determined to document seasonal changes in water uptake by three representative plant species(Pinus sylvestris var. mongolica Litv., Amygdalus pedunculata Pall., and Salix psammophila) in the northeastern Mu Us sandy land, Northwest china. Based on the depth distribution and temporal variation of measured gravimetric soil water content(SWC), the soil water profile of the three species stands was divided into active(0.01 g g^(-1)2..2.. g^(-1)2..), and moist(0.08 g g^(-1)2..g g^(-1), CV >45%) layers. Annually, P. sylvestris, A. pedunculata, and S. psammophila obtained most water from deep(59.2..9.7%, moist layer and groundwater),intermediate(57.4%±9.8%, stable and moist layers), and shallow(54.4%±10.5%, active and stable layers) sources, respectively. Seasonally, the three plant species absorbed more than 60% of their total water uptake from the moist layer and groundwater in the early(June) dry season;then, they switched to the active and stable layers in the rainy season(July–September) for water resources(50.1%–62..%). In the late(October–November) dry season, P. sylvestris(54.5%–66.2.. and A. pedunculata(52..%–63.6%) mainly used water from stable and moist layers, whereas S. psammophila(52..%–70.7%) still extracted water predominantly from active and stable layers. Variations in the soil water profile induced by seasonal fluctuations in precipitation and groundwater levels and discrepancies in plant pheno

关键词： desert ecosystem MixSIAR model plant water uptake soil moisture stable isotopes vegetation restoration water-use efficiency