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Zonal Differences in Correlation Patterns Between Soil Organic Carbon and Climate Factors at Multi-extent

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Chinese Geographical Science 2016年第5期26卷 670-678页

作者： QIN Falyu SHI xuezheng xu shengxiang YU Dongsheng WANG Dandan State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China Guizhou Technology&Information Center of Land and Resources Guiyang 550004China College of Remote Sensing Nanjing University of Information Science&TechnologyNanjing 210044China

Studying the relationship between climate factors and soil organic carbon （SOC） is vitally important. However, how SOC responses to climate （temperature and precipitation） at cohesive extents is poorly studied. Two transects of approximately the same length （transect P and transect T） were selected to examine the variation of SOC content in relation to mean annual temperature （MAT） and mean annual precipitation （MAP）. The coefficients of partial correlation between SOC density and MAT （Rt） and MAP （Rp） were determined to quantify the relationships between SOC density and the two climate factors. The results indicated that for transect T, Rt was statistically significant once the extent level was greater than or equal to two fundamental extent units, while for transect P, Rp showed statistical significance only at extent levels which were greater than two fundamental extent traits. At the same extent levels but in different transects, Rts exhibited no zonal difference, but Rps did once the extent level was greater than two fundamental extent units. Therefore, to study the relationship between SOC density and different climate factors, different minimum extent levels should be ex- amined. The results of this paper could deepen the understanding of the impacts that SOC pool has on terrestrial ecosystem and global carbon cycling.

关键词： soil organic carbon (SOC) mean annual temperature (MAT) mean annual precipitation (MAP) extent level coefficient of partial correlation

土地利用变化对土壤类型的影响——以太仓和昆山两市为例

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土壤 2024年第4期56卷 897-905页

作者：赵治东孙龙辉赵明松刘峰徐胜祥李德成土壤与农业可持续发展重点实验室(中国科学院) 南京211135 安徽理工大学空间信息与测绘工程学院安徽淮南232001 矿山采动灾害空天地协同监测与预警安徽省教育厅重点实验室安徽淮南232001 矿区环境与灾害协同监测煤炭行业工程研究中心安徽淮南232001 中国科学院大学北京100049

选取江苏省太仓市和昆山市作为研究区域,结合当前土地利用方式和历史土壤图资料,通过室内分析确定土地利用方式的变化区域,并设置典型的调查样点,通过野外踏勘确定土地利用方式改变对土壤类型的潜在影响。结果表明:近40年来,太仓和昆山... 详细信息

选取江苏省太仓市和昆山市作为研究区域,结合当前土地利用方式和历史土壤图资料,通过室内分析确定土地利用方式的变化区域,并设置典型的调查样点,通过野外踏勘确定土地利用方式改变对土壤类型的潜在影响。结果表明:近40年来,太仓和昆山的主要土地利用变化方式是水改旱(即由水田转变为水浇地、旱地、园地、林地和草地等),这一变化分别占据了两市土地利用方式变化的98.92%和98.15%。这种显著的土地利用变化对土壤类型产生了明显影响,导致土壤性质发生改变,包括水稻土的犁底层逐渐减少,甚至消失,使其失去了典型的水稻土特征。研究区内土壤类型变化规则的确定主要由土壤质地和人为土地改造方向所影响。值得注意的是,水改旱后如继续旱作,土壤类型可能会由水稻土转为其他类型土壤(如潮土等),但这需要进一步的研究来验证其效果。

关键词：土地利用变化水改旱土壤类型土壤调查

松嫩典型黑土区耕地黑土层厚度数字制图方法比较

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地球信息科学学报 2024年第6期26卷 1452-1468页

作者：郭俊辉刘峰徐胜祥高璐璐赵治东胡文友于东升赵玉国中国科学院南京土壤研究所土壤与农业可持续发展国家重点实验室南京210008 中国科学院大学北京100049 中国科学院南京土壤研究所土壤环境与污染修复重点实验室南京210008 安徽理工大学空间信息与测绘工程学院淮南232001

黑土层厚度与农田土壤肥力和质量密切相关,准确刻画东北松嫩典型黑土区耕地黑土层厚度的空间分布对黑土地保护和农业可持续发展具有重要意义。然而,常用的预测模型在平原漫岗地区进行数字制图具有较大的难度,如何准确预测黑土层厚度的... 详细信息

黑土层厚度与农田土壤肥力和质量密切相关,准确刻画东北松嫩典型黑土区耕地黑土层厚度的空间分布对黑土地保护和农业可持续发展具有重要意义。然而,常用的预测模型在平原漫岗地区进行数字制图具有较大的难度,如何准确预测黑土层厚度的空间分布特征是亟待解决的问题。选取东北地区松嫩典型黑土区作为研究区,以研究区内106个剖面点和45个环境因子为基础数据,通过因子重要性排序和相关性剔除法筛选变量,利用多元线性回归(Multiple Linear Regression,MLR)、随机森林(Random Forest,RF)、梯度提升树(Gradient Boosting Decsion Tree,GBDT)、极端梯度提升(Extreme Gradient Boosting,XGBoost)、随机森林回归克里格(Random Forest-Regression Kriging,RF-RK)和堆叠泛化模型(Stacking)对黑土层厚度进行空间预测制图,评估不同模型预测精度并研究影响黑土层厚度空间分布的最优协变量,并基于较优模型绘制东北黑土区耕地黑土层厚度分级图。结果表明:①Stacking组合多种模型的优点,预测性能表现最佳(R^(2)=0.47,MAE=21.02 cm,RMSE=27.12 cm),其次是RF-RK和RF;②通过变量筛选剔除低贡献度的环境变量后,不同模型的R^(2)平均提高0.11,其中MLR提升幅度最大为0.32;③不同模型预测的松嫩典型黑土区黑土层厚度空间分布趋势基本一致,60 cm以上的黑土层主要分布在研究区的东北部和东南部,而30 cm以下的黑土层主要分布在研究区的西南部。在平原漫岗地区,RF-RK和Stacking可以作为黑土层厚度预测的有效方法,总初级生产力(GPP)、坡度坡长因子(LS)和地表温度最大值合成(LSTm)是模型中最重要的解释变量,且黑土层厚度的空间分布信息能为黑土区耕地黑土保护和农业可持续发展提供数据支持。

关键词：黑土层厚度数字土壤制图变量筛选机器学习随机森林回归克里格堆叠泛化模型空间分异特征最优协变量

Uncertainty and Sensitivity Analyses for Modeling Long-Term Soil Organic Carbon Dynamics of Paddy Soils Under Different Climate-Soil-Management Combinations

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Pedosphere 2017年第5期27卷 912-925页

作者： QIN Fal ZHAO Yongcun SHI xuezheng xu shengxiang YU Dongsheng State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences University of Chinese Academy of Sciences Yuxi Normal University

Reporting modeling results with uncertainty information can benefit decision making by decreasing the extent that variability exerts a disproportionate influence on the options selected. For making decisions with more confidence, the uncertainty interval should be as narrow as possible. Here, the soil organic carbon （SOC） dynamics of the major paddy soil subgroup from 4 different paddy field regions of China （located in 4 counties under different climate-soil-management combinations） were modeled using the DeNitrification- DeComposition （DNDC） model for the period from 1980 to 2008. Uncertainty intervals associated with the SOC dynamics for these 4 subgroups were estimated by a long-term global sensitivity and uncertainty analysis （i. e., the Sobolt method）, and their sensitivities to 7 influential factors were quantified using the total effect sensitivity index. The results, modeled with high confidence, indicated that in the past 29 years, the studied paddy soils in Xinxing, Yixing, and Zhongjiang counties were carbon （C） sinks, while the paddy soil in Helong County was a C source. The 3 C sinks sequestered 12.2 （5.4, 19.6）, 17.1 （8.9, 25.0）, and 16.9 （-1.2, 33.6） t C ha-1 （values in the parentheses are the 5th and 95th percentiles, respectively）. Conversely, the C source had a loss of -5.4 （-14.2, 0.06） t C ha-1 in the past 29 years. The 7 factors, which changed with the climate-soil-management context, exhibited variable influences on modeled SOC. Measures with potential to conserve or sequestrate more C into paddy soils, such as incorporating more crop residues into soils and reducing chemical fertilizer application rates, were recommended for specific soils based on the sensitivity analysis results.

关键词： carbon loss carbon sequestration carbon sink carbon source DeNitrification-DeComposition model fertilizer appli-cation influential factors residue incorporation Sobol~ method

基于RUSLE模型的青藏高原土壤保持功能定量评价

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土壤 2024年第1期56卷 173-181页

作者：刘振坤刘峰郑光辉李德成徐胜祥张甘霖南京信息工程大学地理科学学院南京210044 土壤与农业可持续发展重点实验室(中国科学院) 南京210008 中国科学院大学北京100049 中国科学院流域地理学重点实验室(中国科学院南京地理与湖泊研究所) 南京210008

土壤保持功能是青藏高原生态系统的主要调节功能之一,准确评估青藏高原土壤保持功能的时空变化规律,是确保该地区顺利开展水土保持和生态环境治理工作的前提。本研究通过收集气象、土壤、土地利用、DEM和NDVI等数据,利用RUSLE模型对1982... 详细信息

土壤保持功能是青藏高原生态系统的主要调节功能之一,准确评估青藏高原土壤保持功能的时空变化规律,是确保该地区顺利开展水土保持和生态环境治理工作的前提。本研究通过收集气象、土壤、土地利用、DEM和NDVI等数据,利用RUSLE模型对1982—2020年青藏高原土壤保持功能的时空特征进行动态评估。结果表明:1982—2020年青藏高原的土壤保持量呈波动增加趋势,土壤保持能力由南向北逐渐减弱,高值区主要集中在青藏高原东南部的川西和藏东的高山深谷;在过去的近40 a中,青藏高原土壤侵蚀强度发生明显转换,其主要特征是由高一级的中度侵蚀强度向低一级的轻度或微度侵蚀强度转换,说明青藏高原近40 a内土壤保持状况不断改善;不同地形条件下青藏高原土壤保持能力也有明显差异,主要表现为起伏度小的高海拔地区土壤保持能力普遍较弱;就不同的土地利用类型而言,林地区域的土壤保持能力最强,而未利用地土壤保持能力最弱。近40 a来,青藏高原土壤保持能力不断增强,但仍存在部分区域的土壤保持能力较弱。未来在重视和保护土壤保持能力较强的林地区域的同时,应加强起伏度小的高海拔地区水土治理工作,制定分级分区的土壤侵蚀防治措施,进一步增强青藏高原地区的土壤保持功能。

关键词： GIS RUSLE模型土壤保持功能青藏高原

基于巴林特小组指导的团体心理干预对晚期肝癌介入治疗患者生活质量的影响

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中西医结合护理（中英文） 2024年第7期10卷 163-165页

作者：季孟娟钟海胡小龙徐升祥马强中山市人民医院广东中山528403

目的探讨在行介入治疗的晚期肝癌患者中实施基于巴林特小组指导下的团体心理干预对其生活质量的影响。方法本次研究对象为中山市人民医院于2021年6月至2022年6月收治的90例晚期肝癌介入治疗患者,按照抽签法平均分为2组。对照组45例患者... 详细信息

目的探讨在行介入治疗的晚期肝癌患者中实施基于巴林特小组指导下的团体心理干预对其生活质量的影响。方法本次研究对象为中山市人民医院于2021年6月至2022年6月收治的90例晚期肝癌介入治疗患者,按照抽签法平均分为2组。对照组45例患者采用常规护理,观察组45例患者采用基于巴林特小组指导下的团体心理干预。比较2组患者手术前后的心理状态、自我护理能力、希望水平及生活质量。结果2组在术后14 d、术后1个月的焦虑自评量表和抑郁自评量表评分相较于同组术前均降低,自我护理能力量表、Herth希望量表及癌症患者生活质量量表评分相较于同组术前均升高(P均<0.05);相较于同期对照组,观察组的上述5项评分均更优(P均<0.05)。结论基于巴林特小组指导的团体心理干预可有效改善晚期肝癌介入治疗患者的心理状态,提高其自我护理能力、希望水平及生活质量。

关键词：晚期肝癌介入治疗巴林特小组指导团体心理干预生活质量

Environmental and Anthropogenic Factors Driving Changes in Paddy Soil Organic Matter: A Case Study in the Middle and Lower Yangtze River Plain of China

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Pedosphere 2017年第5期27卷 926-937页

作者： GUO Naijia SHI xuezheng ZHAO Yongcun xu shengxiang WANG Meiyan ZHANG Ganlin WU Jinshui HUANG Biao KONG Chao State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory for Agro-Ecological Processes in Subtropical Regions Institute of Subtropical Agriculture Chinese Academy of Sciences

Changes in soil organic matter(SOM) can affect food security, soil and water conservation, and climate change. However, the drivers of changes in SOM in paddy soils of China are not fully understood because the effects of agricultural management and environmental factors are studied separately. Soil, climate, terrain, and agricultural management data from 6 counties selected based on representative soil types and cropping systems in China were used in correlation analysis, analysis of variance, and cforest modeling to analyze the drivers of changes in SOM in paddy soils in the Middle and Lower Yangtze River Plain from 1980 to 2011. The aims of this study were to identify the main factors driving the changes in SOM and to quantitatively evaluate their individual impacts. Results showed that the paddy SOM stock in the study area increased by 12.5% at an average rate of 0.023 kg myearover the 31-year study period. As a result of long-term rice planting, agricultural management practices had a greater influence than soil properties, climate, and terrain. Among the major drivers, straw incorporation, the most influential driver, together with fertilization and tillage practices, significantly increased the accumulation of SOM, while an increase in temperature significantly influenced SOM decomposition. Therefore, to confront the challenge of rising temperatures, it is important to strengthen the positive effects of agricultural management. Rational fertilizer use for stabilizing grain production and crop straw incorporation are promising measures for potential carbon sequestration in this region.

关键词： agricultural management practices cforest modeling environmental factors carbon sequestration fertilizer use straw incorporation temperature tillage

Influence of Climate on Soil Organic Carbon in Chinese Paddy Soils

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Chinese Geographical Science 2017年第3期27卷 351-361页

作者： WANG Dandan YAN Yechao LI Xinhui SHI xuezheng ZHANG Zhongqi David C WEINDORF WANG Hongjie xu shengxiang School of Geography and Remote Sensing Nanjing University of Information Science & Technology Nanjing 210044 China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008China Jiangsu Normal University Xuzhou 221116 China Department of Plant and Soil Sciences Texas Tech University Lubbock 79409 USA

Soil organic carbon(SOC) is a major component of the global carbon cycle and has a potentially large impact on the greenhouse effect. Paddy soils are important agricultural soils worldwide, especially in Asia. Thus, a better understanding of the relationship between SOC of paddy soils and climate variables is crucial to a robust understanding of the potential effect of climate change on the global carbon cycle. A soil profile data set(n = 1490) from the Second National Soil Survey of China conducted from 1979 to 1994 was used to explore the relationships of SOC density with mean annual temperature(MAT) and mean annual precipitation(MAP) in six soil regions and eight paddy soil subgroups. Results showed that SOC density of paddy soils was negatively correlated with MAT and positively correlated with MAP(P < 0.01). The relationships of SOC density with MAT and MAP were weak and varied among the six soil regions and eight paddy soil subgroups. A preliminary assessment of the response of SOC in Chinese paddy soils to climate indicated that climate could lead to a 13% SOC loss from paddy soils. Compared to other soil regions, paddy soils in Northern China will potentially more sensitive to climate change over the next several decades. Paddy soils in Middle and Lower Yangtze River Basin could be a potential carbon sink. Reducing the climate impact on paddy soil SOC will mitigate the positive feedback loop between SOC release and global climate change.

关键词： soil organic carbon paddy soils mean annual temperature mean annual precipitation climate change

Temporal changes in SSR allelic diversity of major rice cultivars in China

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Journal of Genetics and Genomics 2009年第6期36卷 363-370页

作者： Xinghua Wei Xiaoping Yuan Hanyong Yu Yiping Wang Qun xu shengxiang Tang State Key Laboratory of Rice Biology China National Rice Research Institute Hangzhou 310006 China

Forty simple sequence repeats （SSRs） were used to assess the changes of diversity in 310 major Chinese rice cultivars grown during the 1950s-1990s. Of the 40 SSR loci, 39 were polymorphic. A total of 221 alleles were detected with an average of 5.7 alleles per locus （Na）. The Nei＇s genetic diversity index （He） varied drastically among the loci （0.207 to 0.874, mean 0.625）. Comparing the temporal changes in Na and He, the cultivars from the 1950s had more alleles and higher He scores than the cultivars from the other four decades. Analysis of molecular variance （AMOVA） indicated that the genetic differentiation among the five decades was not significant in the whole set, but significant within indica and japonica. More changes among the decades were revealed in indica cultivars than in japonica cultivars. Some alleles had been lost in current rice cultivars in the 1990s, occurring more frequently in indica. These results suggest that more elite alien genetic resources should be explored to widen the genetic backgrounds of rice cultivars currently grown in China.

关键词： rice (Oryza sativa L.) major varieties SSR genetic diversity AMOVA