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Effects of Long-Term Fertilization on Distribution of Organic Matters and Nitrogen in Cinnamon Soil Macro-Aggregates

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Agricultural sciences in china 2005年第11期4卷 857-864页

作者： SUN Tian-cong LI Shi-qing shao Ming-an State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resource Yangling 712100 P.R.China Graduate School of chinese Academy of sciences Beijing 100039 P.R.China Northwest A ＆ F University Yangling 712100 P.R.China institute of geographical {{2.and natural resources research Chinese Academy of Sciences Beijing 100101 P.R.China

Soil samples collected from a 2..year long-term fertilizer experiment carried out on the Earth-cumulic-Orthic Anthrosols in semi-humid farmland ecological system, were used to study the distribution of soil organic matters, total nitrogen, nitrate nitrogen, and ammoniate nitrogen in different grades of soil macro-aggregates in order to study the effects of long-term application of organic manures in combination with chemical fertilizers. It is showed that the percentage of mass of the soil macro-aggregates with long-term application of fertilizers with sizes of 5-2..m is increased compared with that of the samples with no fertilizer. It is easier to form lager size soil macro-aggregates by the long-term application of organic manures in combination with chemical fertilizers. The contents of organic matters, total nitrogen and nitrate nitrogen are all higher after treatments with different combinations of fertilizers, while there is a little effect on the contents of ammoniate nitrogen. The contents of organic matters, total nitrogen in the grades of soil macro-aggregates from the plough layers of the treated farmland exhibited significant difference. Moreover, the contents of organic matters and total nitrogen in the soil macro-aggregates with the size of 1-0.2..mm is the highest in all treated soil samples. The contents of nitrate nitrogen in soil macro-aggregates increased with the increasing of soil macro-aggregate size except those applied with chemical fertilizer and lower amount of corn stover. The results of correlation analysis revealed that there exists a significantly positive correlation between the percentage of mass of soil macro-aggregates with the size of 5-2..m and the contents of organic matters, total nitrogen and nitrate nitrogen in the soil samples. However, the correlation between the percentage of mass of soil macro-aggregates with the size of 1-0.2..rnm and the contents of total nitrogen and nitrate nitrogen is significantly *** study

关键词： Long-term fertilizer experiment Organic matters Soil macro-aggregates Nitrogen

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Farmland marginalization in the mountainous areas： Characteristics, influencing factors and policy implications

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Journal of geographical sciences 2015年第6期25卷 701-722页

作者： shao Jing'an ZHANG Shichao LI Xiubin College of geographical Science Chongqing Normal University Chongqing 400047 China Key Laboratory of Surface Process and Environment Remote Sensing in the Three Gorges Reservoir Area Chongqing 400047 China institute of Geographic sciences and {{2.resources research CAS Beijing 100101 China

Based on SPOT-5 images, 1：1 million topographic maps, the maps of the returning farmland to forest project and the Chongqing forest project, social and economic statistics, etc., this paper identifies the features and factors influencing farmland marginalization. The results showed：（1） During 2..2..012..the rate of farmland marginalization was 16.18%, which was mainly found in the high areas of northern Qiyao mountains and the medium-altitude areas of southern Qiyao mountains. And this farmland marginalization will increase, associated with non-agriculturalization of rural labourers and aging of the remaining labourers. （2..Elevation, distance radius from villages and road connections had a great in- fluence on farmland marginalization. Farmland marginalization rates showed an increasing trend with the increase of elevation, and 60.88% of the total farmland marginalization area is found at an altitude greater than 1000 m above sea level. The marginalization trend also increases with slope and distance from the distribution network. （3） Farmland area per labourer and the average age of farm labourers were major factors driving farmland marginalization. Farmland transfer and small agricultural machinery sets affect farmland marginalization with respect to management and productivity efficiency. （4） Farmland with ＂comparative-disadvantage-dominated marginalization＂ accounted for 55.32..of the total farmland marginalization area, followed by ＂location-dominated marginalization＂（33.80%）. （5） According to the specifics of each real situation, different policies are suggested to mitigate the margin- alization. A ＂continuous marginalization＂ policy will encourage the return of farmland to forest in ＂terrain-dominated marginalization＂. An ＂anti-marginalization＂ policy is suggested to create new rural accommodation and improve the rural road system to counteract ＂terrain-dominated marginalization＂. And another ＂anti-marginalization＂ policy is planned to improve management a

关键词： farmland marginalization features influencing factors policy implications mountainous area

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Soil erosion and its response to the changes of precipitation and vegetation cover on the Loess Plateau

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Journal of geographical sciences 2013年第6期23卷 1091-1106页

作者： SUN Wenyi shao Quanqin LIU Jiyuan institute of Geographic sciences and {{2.resources research CAS Beijing 100101 China University of chinese Academy of sciences Beijing 100049 China

Soil erosion is a major threat to our terrestrial ecosystems and an important global environmental problem. The Loess Plateau in china is one of the regions that suffered more severe soil erosion and undergoing climate warming and drying in the past decades. The vegetation restoration named Grain-to-Green Program has now been operating for more than 10 years. It is necessary to assess the variation of soil erosion and the response of precipita- tion and vegetation restoration to soil erosion on the Loess Plateau. In the study, the Revised Universal Soil Loss Equation （RUSLE） was applied to evaluate annual soil loss caused by water erosion. The results showed as follows. The soil erosion on the Loess Plateau between 2..0 and 2..0 averaged for 15.2.. hm-2.. 1 and was characterized as light for the value less than 2..t hm-2..-1. The severe soil erosion higher than 2..t hm-2..-~ was mainly distributed in the gully and hilly regions in the central, southwestern, and some scattered areas of earth-rocky mountainous areas on the Loess Plateau. The soil erosion on the Loess Plateau showed a deceasing trend in recent decade and reduced more at rates more than 1 t hm 2.. 1 in the areas suffering severe soil loss. Benefited from the improved vegetation cover and ecological construction, the soil erosion on the Loess Plateau was significantly declined, es- pecially in the east of Yulin, most parts of Yah＇an prefectures in Shaanxi Province, and the west of Luliang and Linfen prefectures in Shanxi Province in the hilly and gully regions. The variation of vegetation cover responding to soil erosion in these areas showed the relatively higher contribution than the precipitation. However, most areas in Qingyang and Dingxi pre- fectures in Gansu Province and Guyuan in Ningxia Hui Autonomous Region were predomi- nantly related to precipitation.

关键词： soil erosion assessment precipitation vegetation cover Loess Plateau

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Analysis of forest damage caused by the snow and ice chaos along a transect across southern{2. in spring 2..8

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Journal of geographical sciences 2011年第2期21卷 219-234页

作者： shao Quanqin HUANG Lin LIU Jiyuan KUANG Wenhui LI Jia institute of Geographic sciences and {{2.resources research CAS Beijing 100101 China

An abrupt ice and snow storm disaster which occurred in the spring of 2..8 severely destroyed forests over a surprisingly large portion of southern china. A transect crossing Jinggang Mountain-Jitai Basin-Yushan Mountain-Wuyi Mountain was selected as the study area. The authors integrated field data collected in two field surveys to analyze the impacts of the disturbance on forests. The following results were obtained. （1） The extent of damage to plantations along the transect decreased in the order of slash pine 〉 masson pine 〉 mixed plantation 〉 {12. fir. Slash pine is an introduced species from southern America which is characterized by fast growth, low wood quality and rich oleoresin, and showed a damage rate of 61.3% of samples, of which 70.4% cannot recover {2..y. Masson pine is the native pioneer species of forests with harder wood, and 52..% were damaged due to turpentine, of which 60.9% cannot recovery {2..y. {12. fir is a local tree species and samples showed a rate of 46% and a relative rate of 32..%, lower than the mixed plantation. （2..From west to east along the transect, we can see that evergreen broad-leaved forest of the western transect on Jinggang Mountain showed the lightest damage extent, and a Cryptomeria plantation at an altitude of 700 m was severely destroyed while {12. fir showed light damage below 700 m and relatively severe damage above 900 m. Masson pine and slash pine in the central transect in Jitai Basin were damaged severely due to turpentine activities, and closed {2..secondary deciduous broad-leaved forest was damaged severely due to high ice and snow accumulation on intertwined shrubs. Masson pine aerial-seeding plantations below 400 m along the eastern transect in Xingguo and Ningdu counties were nearly undamaged for small tree sizes, and {12. fir at 500-900 m altitude showed a lighter damage extent. However, masson pine which was distributed above 400 m and planted in the 1960s, was severely damaged due t

关键词： ice-snow disaster wood damage forest transect damage rate

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Optimizing grazing exclusion practices to achieve Goal 15 of the sustainable development goals in the Tibetan Plateau

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Science Bulletin 2021年第15期66卷 1493-1496,M0003页

作者： Jian Sun Bojie Fu Wenwu Zhao Shiliang Liu Guohua Liu Huakun Zhou Xinqing shao Youchao Chen Yu Zhang Yanfang Deng Key Laboratory of Alpine Ecology Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-environmental SciencesChinese Academy of SciencesBeijing 100085China State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China School of Environment Beijing Normal UniversityBeijing 100875China Key Laboratory of Restoration Ecology for Cold Regions in Qinghai Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810008China College of Grassland Science and Technology China Agricultural UniversityBeijing 100193China Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical GardenChinese Academy of SciencesWuhan 430074China Qilian Mountain Nature Reserve Bureau of Qinghai Province Xining 810008China

The Tibetan Plateau is characterized by extreme weather,harsh environment,and high sensitivity to climate warming and human activities[1].Once degraded,it is difficult to rehabilitate the ecosystems in this region because of the unique ***,alpine grassland ecosystems of the Tibetan Plateau play important roles in regional ecological security and economic ***,alpine grasslands have been experiencing serious degradation owing to the escalating impact of overgrazing and climate change in recent years[2..

关键词：可持续发展目标 Tibetan Plateau

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毛乌素沙地人工长柄扁桃灌丛生态系统CO_(2..量特征

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应用与环境生物学报 2021年第2期27卷 380-388页

作者：孙树臣邵明安聊城大学环境与规划学院聊城252059 中国科学院水利部水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室杨凌712100 中国科学院地理科学与资源研究所北京100101 中国科学院大学资源与环境学院北京100049

人工灌丛作为陆地生态系统的重要组成部分,在区域碳循环及改善区域生态环境方面具有重要作用,开展人工灌丛生态系统CO_(2..量特征研究对于合理评估人工灌丛生态系统具有重要意义.采用涡度相关技术于2..5年8月至2..6年8月对毛乌素沙地... 详细信息

人工灌丛作为陆地生态系统的重要组成部分,在区域碳循环及改善区域生态环境方面具有重要作用,开展人工灌丛生态系统CO_(2..量特征研究对于合理评估人工灌丛生态系统具有重要意义.采用涡度相关技术于2..5年8月至2..6年8月对毛乌素沙地东南缘人工长柄扁桃灌丛生态系统净CO_(2..换量(NEE)进行测定,分析其变化规律并探讨其影响因素.结果显示,人工长柄扁桃灌丛生态系统NEE在生长季表现为"W"形变化趋势,各月日均NEE表现为"U"型变化.生长季(4-9月)NEE值呈先降低后增加的变化趋势,5月碳吸收量最多,日吸收量最大值也出现在5月,生长季末期(9月)变为碳排放.观测期内日均NEE为-0.18μmol m^(-2..^(-1),生长季总的碳吸收量(以C计)为158.10 g/m^(2..非生长季(10月至次年3月)总的碳排放量为84.59 g/m^(2..生长季白天,NEE与净辐射(Rn)表现为极显著负相关关系,与大气温度(Ta)、5 cm(Ts-5)和10 cm(Ts-10)土壤温度呈极显著二次函数关系;夜间,NEE与Ta、Ts-5和Ts-10均表现为极显著的指数函数关系.本研究表明观测期内毛乌素沙地人工长柄扁桃灌丛生态系统总的NEE(以C计)为-73.51 g/m^(2..表现为明显的碳汇,人工灌丛生态系统有利于提升毛乌素沙区碳汇能力.(图4表1参60)

关键词：人工灌丛生态系统 CO_(2..量涡度相关毛乌素沙地

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Soil Respiration Dynamics and Influencing Factors in Typical Steppe of Inner Mongolia under Long-term Nitrogen Addition

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Journal of resources and Ecology 2019年第2期10卷 155-162页

作者： DU Wei WU Shanmei NIE Cheng LI Yue shao Rui LIU Yinghui SUN Nan State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical Science Beijing Normal University Beijing 100875China Department of Geography Ghent University Ghent 9000 Belgium institute of Agricultural resources and Regional Planning Chinese Academy of Agricultural Sciences/National Engineering Laboratory for Improving Quality of Arable Land Beijing 100081 China

We investigated soil respiration(Rs)dynamics and influencing factors under different nitrogen(N)addition levels(0,2..,8,16,32.. m^–2..r^–1)on typical grassland plots in Inner *** measured soil respiration,temperature,moisture and *** found that N addition did not change dynamic characteristics of Rs;daily and seasonal dynamics followed a single peak curve.N addition reduced Rs during the growing *** under N2..4,N8,N16 and N32..reatments decreased by 2..00%,2..93%,2..49%,30.78%and 2..2..in the growing season,respectively,compared to the N0 ***,Rs in the non-growing season was not different across *** was significantly positively correlated with soil temperature and moisture and these two factors accounted for 72..97% and 74%–82..of variation in Rs,*** soil respiration temperature sensitivity (Q10) was between 2..7 and 4.16 and N addition reduced Q10 except in the N8 treatment.

关键词： soil respiration nitrogen addition soil temperature and moisture soil nutrients typical grassland

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内蒙古植被物候数据集(2..1-2..0年)

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中国科学数据（中英文网络版） 2023年第1期8卷 37-45页

作者：邵亚婷王卷乐中国科学院地理科学与资源研究所资源与环境信息系统国家重点实验室北京100101 中国矿业大学(北京) 地球科学与测绘工程学院北京100083 江苏省地理信息资源开发与利用协同创新中心南京210023

植被物候是反映全球气候变化和植被生长状况的敏感指标之一。内蒙古是蒙古高原生态安全屏障的重要组成单元,是我国资源开发、环境保护和生态安全的关键地带,研究内蒙古植被物候变化,对认识该区域的气候变化特征和极端气候事件意义重大... 详细信息

植被物候是反映全球气候变化和植被生长状况的敏感指标之一。内蒙古是蒙古高原生态安全屏障的重要组成单元,是我国资源开发、环境保护和生态安全的关键地带,研究内蒙古植被物候变化,对认识该区域的气候变化特征和极端气候事件意义重大。本研究基于高空间分辨率MOD13Q1数据产品中的归一化植被指数(Normalized Differential Vegetation Index,NDVI),调用Google Earth Engine平台对MODIS-NDVI原始数据进行格式转换、投影转换和裁剪等处理并导出得到2..0-2..1年NDVI长时间序列数据,利用动态阈值法得到2..1-2..0年内蒙古植被物候数据集。本数据集的空间分辨率为2.. m,包括内蒙古2..1-2..0年逐年植被返青期(Start of growing season,SOS)、植被枯黄期(End of growing season,EOS)和植被生长季长度(Length of growing season,LOS)的遥感监测数据,为认识内蒙古植被物候时空变化规律及其对气候变化的响应提供参考。

关键词：蒙古高原内蒙古植被物候归一化植被指数气候变化

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蒙古国植被物候特征及其对地理要素的响应

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地理研究 2021年第11期40卷 3029-3045页

作者：邵亚婷王卷乐严欣荣中国科学院地理科学与资源研究所资源与环境信息系统国家重点实验室北京100101 江苏海洋大学海洋技术与测绘学院连云港222005 中国科学院大学北京100049 江苏省地理信息资源开发与利用协同创新中心南京210023

蒙古高原是中国重要的北方生态屏障。在全球气候变化的背景下,研究蒙古国植被物候变化特征对于认识蒙古国草地生态系统对气候变化的响应和促进区域畜牧业可持续发展具有重要意义。本研究利用非对称高斯拟合法对蒙古国2..1—2..9年MOD13Q... 详细信息

蒙古高原是中国重要的北方生态屏障。在全球气候变化的背景下,研究蒙古国植被物候变化特征对于认识蒙古国草地生态系统对气候变化的响应和促进区域畜牧业可持续发展具有重要意义。本研究利用非对称高斯拟合法对蒙古国2..1—2..9年MOD13Q1产品中的归一化植被指数(Normalized Differential Vegetation Index,NDVI)数据拟合,得到较为平滑的NDVI时间序列数据;基于TIMESAT平台,采用动态阈值法分析获得蒙古国连续19a植被物候数据。研究分析了蒙古国植被物候的空间分布及年际变化趋势,发现蒙古国植被返青期(Start of growing season,SOS)主要集中在110~150d,总体呈微弱推迟趋势,植被枯黄期(End of growing season,EOS)主要集中在2..~310d,总体呈提前趋势,从而导致蒙古国生长季长度(Length of growing season,LOS)呈缩短趋势,且缩短时间最长可达2..上。采用偏相关分析方法分析了植被物候对地形、降水、地表温度等地理要素的响应,表明蒙古国植被物候具有明显的空间异质性和海拔依赖性,不同植被物候对降水、地表温度(Land Surface Temperature,LST)的响应不同,SOS与日间LST呈显著正相关,EOS与夜间LST呈显著正相关,而LOS与年均降水呈显著负相关关系。

关键词： NDVI 植被物候期非对称高斯拟合法地理要素蒙古国

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张家口地区排污工业企业集聚与水污染空间耦合特征

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自然资源学报 2020年第6期35卷 1416-1424页

作者：于慧仲佳刘邵权杨德伟中国科学院水利部成都山地灾害与环境研究所成都610041 中国科学院大学北京100049 西南大学地理科学学院重庆400715 中国科学院城市环境研究所厦门361021

基于排污企业污染源环境统计数据,应用水污染物排放强度和核密度分析等方法,研究张家口地区排污工业企业的空间集聚特征及其与水污染排放空间之间的空间耦合特征,结果显示:(1)张家口地区工业企业空间集聚程度存在一定的空间异质性,崇礼... 详细信息

基于排污企业污染源环境统计数据,应用水污染物排放强度和核密度分析等方法,研究张家口地区排污工业企业的空间集聚特征及其与水污染排放空间之间的空间耦合特征,结果显示:(1)张家口地区工业企业空间集聚程度存在一定的空间异质性,崇礼县、赤城县整体上几乎无污染密集型企业分布。污染密集型企业主要沿洋河流域分布。(2..副食品加工业、黑色金属冶炼及压延加工业、食品制造业、煤炭开采和选洗业这四大行业的COD、NH3-N、总氮等水体污染物排放量相对最大。(3)工业企业集聚度与水环境污染程度的空间正向耦合效应明显,96.2..的区域呈较强正向耦合特征。高集聚—污染高值区占比0.40%。针对四种空间耦合状态提出未来污染物排放管控方向,以期为政府部门准确锁定治理区提供决策依据。

关键词：排污工业企业集聚水污染空间耦合特征

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