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| 1 | Development of a New Index for Integrating Landscape Patterns with Ecological Processes at Watershed Scale显示文摘Understanding the relationship between landscape patterns and ecological processes has been a central yet challenging research theme in landscape ecology. Over the past decades,many landscape metrics have been proposed but few directly incorporated ecological processes. In this paper,we developed a landscape index,namely,location-weighted landscape index(LWLI) to highlight the role of landscape type in ecological processes,such as nutrient losses and soil erosion. Within the framework of the Lorenz curve theory,we develop this index by integrating landscape pattern and point-based measurements at a watershed scale. The index can be used to characterize the contribution of landscape pattern to ecological processes(e.g. nutrient losses) with respect to a specific monitoring point in a watershed. Through a case study on nutrient losses in an agricultural area in northeastern China,we found that nutrient losses tended to be higher for a watershed with a higher LWLI value,and vice versa. It implied that LWLI can be used to evaluate the potential risk of nutrient losses or soil erosion by comparing their values across watersheds. In addition,this index can be extended to characterize ecological processes,such as the effect of landscape pattern on wildlife inhabitation and urban heat island effect. Finally,we discuss several problems that should be paid attention to when applying this index to a heterogeneous landscape site. | CHEN Liding TIAN Huiying FU Bojie ZHAO Xinfeng | 2009 | Chinese Geographical Science2009，19，1： | 38 |
| 2 | A proposal for the theoretical analysis of the interactive coupled effects between urbanization and the eco-environment in mega-urban agglomerations显示文摘Mega-urban agglomerations are strategic core areas for national economic development and the main regions of new urbanization. They also have important roles in shifting the global economic center of gravity to China. However, the development of mega-urban agglomerations has triggered the interactive coercion between resources and the eco-environment. The interactive coupled effects between urbanization and the eco-environment in mega-urban agglomerations represent frontier and high-priority research topics in the field of Earth system science over the next decade. In this paper, we carried out systematic theoretical analysis of the interactive coupling mechanisms and coercing effects between urbanization and the eco-environment in mega-urban agglomerations. In detail, we analyzed the nonlinear-coupled relationships and the coupling characteristics between natural and human elements in mega-urban agglomerations. We also investigated the interactive coercion intensities between internal and external elements, and the mechanisms and patterns of local couplings and telecouplings in mega-urban agglomeration systems, which are affected by key internal and external control elements. In addition, we proposed the interactive coupling theory on urbanization and the eco-environment in mega-urban agglomerations. Furthermore, we established a spatiotemporal dynamic coupling model with multi-element, multi-scale, multi-scenario, multi-module and multi-agent integrations, which can be used to develop an intelligent decision support system for sustainable development of mega-urban agglomerations. In general, our research may provide theoretical guidance and method support to solve problems related to mega-urban agglomerations and maintain their sustainable development. | FANG Chuanglin ZHOU Chenghu GU Chaolin CHEN Liding LI Shuangcheng | 2017 | Journal of Geographical Sciences2017，27，12： | 36 |
| 3 | The effect of land use structure on the distribution of soil nutrients in the hilly area of the Loess Plateau,China显示文摘The irrational land use is one of the main reasons for the soil erosion and nutrient loss in the loess hilly area of China. In this project, 4 types of typical land use structure of sustain ment for about 15 years in the loess hill slope are selected to study the effect of land use structure on the distribution of soil nutrients. From hill bottom to hill top, the patterns of land use types are:, grassland-slope farmland-forest, slope farmland-grassland-forest, terrace-grassland-forest and slope farmland-forest-grassland. By measuring the contents of the total N, total P, available N, available P and organic matter of soils, the results show that the land use structure types of slope farmland-grassland-forest and terrace-grassland-forest have a better capacity to maintain the soil nutrients. | Bojie Fu Keming Ma Huafeng Zhou Liding Chen | 1999 | Chinese Science Bulletin1999，44，8： | 32 |
| 4 | A MULTISCALE SOIL LOSS EVALUATION INDEX显示文摘Exploring the relationships between land use and soil erosion at different scales is a fron-tier research field and a hot spot topic in contempo-rary physical geography. Based on the scale-pattern-process theory in landscape ecology and with consideration of such influential factors as land use, topography, soil and rainfall, this paper ap-plies the scale transition method to establishing a soil loss evaluation index at different scales and puts forward a research path and methodology for mul-tiscale soil loss evaluation indices. The multiscale soil loss evaluation index is applied to the evaluation of relationships between land use and soil erosion and the research of soil erosion evaluation at multiple scales. It provides a new method for optimizing the design of regional land use patterns and integrated multiscale research. | FU Bojie ZHAO Wenwu CHEN Liding Lü Yihe WANG De | 2006 | Chinese Science Bulletin2006，51，4： | 22 |
| 5 | Soil contamination with antibiotics in a typical peri-urban area in eastern China: Seasonal variation, risk assessment, and microbial responses显示文摘The prevalence and persistence of antibiotics in soils has become an emerging environmental issue and an increasing threat to soil security and global public health. The problem is more severe in areas undergoing rapid urbanization; however, the ecological risks of antibiotics,seasonal variability, and associated soil microbial responses in peri-urban soils have not been well-explored. The seasonal soil sampling campaigns were conducted in a typical peri-urban watershed in eastern China to investigate distribution of antibiotics. The results demonstrated higher mean concentrations of most antibiotic compounds in winter than in summer in periurban soils. The seasonal variations of norfloxacin, enrofloxacin, and ciprofloxacin were more significant than those of other antibiotics, due to their higher migration ability and bioavailability.An ecological risk assessment demonstrated that chlortetracycline, ciprofloxacin, doxycycline,and ofloxacin can pose high risks to soil microorganisms. Furthermore, the coexistence of multiple antibiotics obviously poses higher risks than individual compounds. A redundancy analysis demonstrated that tetracyclines mainly showed negative correlations with Firmicutes and Chloroflexi, and quinolones showed obviously negative correlations with Acidobacteria,Gemmatimonadetes, and Nitrospirae, suggesting potential inhibition from antibiotics on biological activities or biodegradation processes. However, the persistence of antibiotics in soil results in a significant decrease in bacterial diversity and a change in dominant species.Our results provide an overview of the seasonal variability of antibiotics and the associated effects on bacterial communities in peri-urban soils. The results can provide scientific guidance on decreasing soil contamination with antibiotics to enhance soil security in similar areas. | Fangkai Zhao Lei Yang Liding Chen Qian Xiang Shoujuan Li Long Sun Xinwei Yu Li Fang | 2019 | Journal of Environmental Sciences2019，31，5： | 19 |
| 6 | Identification on threshold and efficiency of rainfall replenishment to soil water in semi-arid loess hilly areas显示文摘As one critical source of water for maintaining ecosystems in arid and semi-arid regions, rainfall replenishment to soil water can determine vegetation growth and ecosystem functions. However, the limited rainfall resources were often not used effectively in the semi-arid loess hilly areas due to random temporal and spatial distribution of rainfall and specific vegetation features. Thus, it is highly significant to determine the threshold and efficiency of rainfall replenishment to soil water under different vegetation types. The threshold and efficiency can offer scientific evidence for rehabilitating vegetation and improving efficiency of using rainfall resources. In this study, the efficiency and threshold of rainfall replenishment to soil water were determined under natural grassland, wheat, artificial grassland, sea buckthorn shrubland and Chinese pine forestland based on consecutive measurements. The results indicated that the lag-time, rate, efficiency of rainfall replenishment to soil water were closely related to vegetation type, with significant differences existing among different vegetation types. The lag-time for natural grassland in the soil horizon of 20 cm was the shortest one(26.4 h), followed by wheat(27.8 h), sea buckthorn(41.8 h), artificial grassland(50.0 h) and Chinese pine(81.8 h).The value of replenishment rate, followed the order of wheat(0.40 mm h^(-1))> natural grassland(0.30 mm h(-1))> sea buckthorn(0.17 mm h(-1))> artificial grassland(0.14 mm h(-1))> Chinese pine(0.09 mm h(-1)). As for the efficiency of rainfall replenishment to soil water, natural grassland was the most efficient one(35.1%), followed by wheat(29.2%), sea buckthorn(16.8%), artificial grassland(11.5%), Chinese pine(4.2%). At last, it was found that wheat had the lowest threshold(6.8 mm) of rainfall replenishment to soil water, which was followed by natural grassland(10.5 mm), sea buckthorn(20.5 mm), artificial grassland(22.6 mm) and Chinese pine(26.4 mm). These results implied that soil water in natural grassland was sensitive to rainfall and easily to be replenished, while soil water in Chinese pine was harder to be replenished by rainfall compared to other vegetation types. | Lei YANG Handan ZHANG Liding CHEN | 2018 | Science China Earth Sciences2018，61，3： | 17 |
| 7 | Major advances in studies of the physical geography and living environment of China during the past 70 years and future prospects显示文摘The natural environment provides material essentials for human survival and development. The characteristics,processes, regional differentiation and forcing mechanisms of the elements of the natural environment(e.g. geomorphology,climate, hydrology, soil, etc.) are the main objects of research in physical geography. China has a complex natural environment and huge regional differentiation and therefore it provides outstanding reserach opportunities in physical geography. This review summarizes the most important developments and the main contributions of research in the physical geography and human living environment in China during the past 70 years. The major topics addressed are the uplift of the Tibetan Plateau and the evolution of its cryosphere, the development of fluvial systems, the acidification of the vast arid region of the Asian interior, variations in the monsoon and westerly climate systems on multiple timescales, the development of lakes and wetlands, the watershed system model, soil erosion, past human-environment interactions, biogeography, and physical geographic zonality. After briefly introducing international research developments, we review the history of research in physical geography in China, focusing on the major achievements and major academic debates, and finally we summarize the status of current research and the future prospects. We propose that in the context of the national demand for the construction of an ecological civilization, we should make full use of the research findings of physical geography, and determine the patterns and mechanisms of natural environmental processes in order to continue to promote the continued contribution of physical geography to national development strategies, and to further contribute to the theory of physical geography from a global perspective. | Fahu CHEN Bojie FU Jun XIA Duo WU Shaohong WU Yili ZHANG Hang SUN Yu LIU Xiaomin FANG Boqiang QIN Xin LI Tingjun ZHANG Baoyuan LIU Zhibao DONG Shugui HOU Lide TIAN Baiqing XU Guanghui DONG Jingyun ZHENG Wei YANG Xin WANG Zaijun LI Fei Wang Zhenbo HU Jie WANG Jianbao LIU Jianhui CHEN Wei HUANG Juzhi HOU Qiufang CAI Hao LONG Ming JIANG Yaxian HU Xiaoming FENG Xingguo MO Xiaoyan YANG Dongju ZHANG Xiuhong WANG Yunhe YIN Xiaochen LIU | 2019 | Science China Earth Sciences2019，62，11： | 11 |
| 8 | Source-sink landscape theory and its ecological significance显示文摘Exploring the relationships between landscape pattern and ecological processes is the key topic of landscape ecology,for which,a large number of indices as well as landscape pattern analysis model were developed.However,one problem faced by landscape ecologists is that it is hard to link the landscape indices with a specific ecological process.Linking landscape pattern and ecological processes has become a challenge for landscape ecologists.“Source”and“sink”are common concepts used in air pollution research,by which the movement direction and pattern of different pollutants in air can be clearly identified.In fact,for any ecological process,the research can be considered as a balance between the source and the sink in space.Thus,the concepts of“source”and“sink”could be implemented to the research of landscape pattern and ecological processes.In this paper,a theory of sourcesink landscape was proposed,which include:(1)In the research of landscape pattern and ecological process,all landscape types can be divided into two groups,“source”landscape and“sink”landscape.“Source”landscape contributes positively to the ecological process,while“sink”landscape is unhelpful to the ecological process.(2)Both landscapes are recognized with regard to the specific ecological process.“Source”landscape in a target ecological process may change into a“sink”landscape as in another ecological process.Therefore,the ecological process should be determined before“source”or“sink”landscape were defined.(3)The key point to distinguish“source”landscape from“sink”landscape is to quantify the effect of landscape on ecological process.The positive effect is made by“source”landscape,and the negative effect by“sink”landscape.(4)For the same ecological process,the contribution of“source”landscapes may vary,and it is the same to the“sink”landscapes.It is required to determine the weight of each landscape type on ecological processes.(5)The sourcesink principle can be applied to non-point source pollution control,biologic diversity protection,urban heat island effect mitigation,etc.However,the landscape evaluation models need to be calibrated respectively,because different ecological processes correspond with different source-sink landscapes and evaluation models for the different study areas.This theory is helpful to further study landscape pattern and ecological process,and offers a basis for new landscape index design. | Liding CHEN Bojie FU Wenwu ZHAO | 2008 | Frontiers in Biology2008，3，2： | 6 |
| 9 | A conceptual model for a process-oriented landscape pattern analysis显示文摘Linking landscape patterns to specific ecological processes has been and will continue to be the key topic in landscape ecology.However,this goal is difficult to achieve by using the traditional landscape metric based on the Patch-Mosaic Model(PMM),as they don’t integrate ecological processes with landscape patterns.In this paper,we proposed a conceptual model,i.e.,the Source-Pathway-Sink Model(SPSM),which designates the role of a landscape unit into 'source', 'sink',or 'pathway' based on specific ecological processes during the landscape pattern analysis.While the traditional landscape metrics derived from the PMM model is visual-or geometrical-oriented and lack of linkage to ecological significance,the SPSM model is process-oriented,dynamic,and scale dependent.A comparison between the PMM and the SPSM models shows that the SPSM model is complementary to the PMM model,and can provide a simple and dynamic perspective on landscape pattern analysis.The SPSM model may represent a conceptual innovation in landscape ecology. | Liding CHEN Ranhao SUN Yihe LU | 2019 | Science China Earth Sciences2019，62，12： | 6 |
| 10 | Effects of riparian vegetation patterns on the distribution and potential loss of soil nutrients: a case study of the Wenyu River in Beijing显示文摘一个河边的生态系统是在一条河隧道和陆上的生态系统之间的一个生态的转变地区。河边的生态系统在维持溪流健康和银行稳定起一个重要作用。因为人的活动,河边的植被的类型沿着 Wenyu 河极大地变化了。这研究由于土壤营养素损失在水污染上检验河边的植被模式的影响。到高地的来自河隧道的四个河边的植被模式被选择为这研究的焦点:草地,农田,草地农田,和 grassland-manmade 草坪。沿着植被模式和滋养的损失的潜在的风险的土壤营养素的不同分布被观察并且比较。结果证明河边的农田有全部的氮(TN ) 的最低价值,全部的磷(TP ) ,可得到的氮(一) ,可得到的磷(AP ) ,和有机物(OM ) ,但是它有最高的土壤体积密度(BD ) 。土壤 TN 的分布, TP,一, AP,和 OM 为河边的农田向河隧道从高地展出了一个衰退趋势,而一个不同趋势为河边的草地被观察。草地农田和 grassland-manmade 草坪的植被模式证明在更低的斜坡的草地有更多的营养素和 OM,但是在上面的斜坡比农田或 manmade 草坪降低土壤 BD。那么,降低斜坡的草地可以从高地拦截并且渗透表面流量。降低斜坡的草地有土壤 TN 的高水平, TP,一,并且 AP,并且因此,它可以成为滋养的损失的新来源。我们的结果建议河边的植被的管理应该被改进,特别地在浓密地占据的区域,到控制土壤侵蚀和河污染。 | Erhui GUO Liding CHEN Ranhao SUN Zhaoming WANG | 2015 | Frontiers of Environmental Science & Engineering2015，9，2： | 6 |
| 11 | Static Schedule Generation for Time-Triggered Ethernet Based on Fuzzy Particle Swarm Optimization显示文摘In time-triggered ethernet(TTEthernet),designing and optimizing the static scheduling of TT messages to improve the real-time performance of the whole network control system is important.When there is a high load on TTEthernet network communication,the conventional static scheduling policy introduces certain problems,such as increased packet loss rate,load imbalance,and transmission delay.Meanwhile,basic artificial intelligence algorithms generally features convergence within only a few steps,leading to higher probability to fall into a local optimal solution.To realize these targets,Fuzzy particle swarm optimization(FPSO)based on population diversity is established.By combining Particle swarm optimization(PSO)with a fuzzy algorithm,setting the adjustment of the inertia weight and the regulation of the mutation factor as the controlled variables of the Fuzzy logic controller(FLC),and adjusting the FLC inference rules,a novel static schedule generation for TTEthernet is proposed.Simulation results prove that,compared to the conventional rate-monotonic scheduling algorithm and the PSO algorithm,FPSO has a strong global search capability when the communication of the TTEthernet system is in a high-load state.FPSO improves the load balancing of the network and reduces the transmission delay of TT message packets.FPSO shows excellent ability to optimize scheduling tables and guarantee the real-time performance of the TTEthernet system. | CHEN Huang WANG Lide SHEN Ping DI Jun | 2019 | Chinese Journal of Electronics2019，28，6： | 5 |
| 12 | Occurrence, spatial distribution and ecological risks of antibiotics in soil in urban agglomeration显示文摘Antibiotics in soil environment are regarded as emerging pollutants and have introduced increasing risks to soil ecosystem and human health in rapid urbanization areas. Identifying the occurrence and spatial variability of antibiotics in soils is an urgent issue in sustaining soil security. In this study, antibiotics in soils were investigated and analyzed in BeijingTianjin-Hebei urban agglomeration. The occurrence, spatial distribution, and related affecting factors of antibiotics in soils were identified and ecological risks of antibiotics in soil environment were assessed. Results showed that(1) The mean concentration of soil antibiotics in Beijing-Tianjin-Hebei urban agglomeration was 21.79 μg/kg. Land use substantially affected the occurrence and concentration of antibiotics in soils. Concentrations of antibiotics in cropland and orchard soils were 2-3 times higher than the other land use types.(2)The concentrations of antibiotics in soils in Beijing-Tianjin-Hebei urban agglomeration presented a spatial pattern of high values in southeast, and low values in northwest. Spatial variability of antibiotics in soils was closely related to the application of organic fertilizer and wastewater irrigation as well as topographical features. Furthermore, soil properties and land management policy had substantial influences on soil antibiotics, and soil heavy metals may aggravate the accumulation of antibiotics in soils.(3) Ecological risks assessment of antibiotics in soils demonstrated that erythromycin(ERY), sulfamethoxazole(SMX), and doxycycline(DOX) may introduce high risks to soil ecosystem health, and more attention should be paid to the areas with intensive human activities that had potential high risk to soil ecosystem health. This study suggests that scientific land and soil management should be considered to prevent soil antibiotic pollution and sustain soil security in urban agglomeration. | Min Li Lei Yang Haw Yen Fangkai Zhao Xinmiao Wang Tianhui Zhou Qingyu Feng Liding Chen | 2023 | Journal of Environmental Sciences2023，，3： | 5 |
| 13 | Effect of Agricultural Land Use Changes on Soil Nutrient Use Efficiency in an Agricultural Area,Beijing,China显示文摘Agricultural land use and management practices may affect soil properties,which play a critical role in sustaining crop production.Since the late 1970s,several new agricultural land use types had been introduced in the rural areas of China.The purpose of this study is to evaluate the effect of these land use changes on the soil properties,nu-trient absorption rate,and nutrient use economic efficiency ratio in an agricultural area of Beijing.Specifically,the cropland,the orchard and the vegetable field were examined.Results of this study suggest that land use and farming management practices significantly affect the content of soil organic carbon (SOC),total nitrogen (TN),total phos-phorus (TP),and available phosphorus in the surface layer of 0-25 cm (p<0.05) in the Yanqing Basin,northwestern Beijing.Soil nutrients in each agricultural land use type decrease rapidly with the increasing soil depth.Orchard and vegetable field tend to have higher soil nutrients than the cropland does.However,the soil nutrient-absorption rate (NAR) of the orchard and vegetable field is lower than that of the cropland,even though orchard and vegetable field may provide much higher economic benefit.While increasing SOC,TN,and TP in the orchard and vegetable field by intensive farming may be a valuable option to improve soil quality,potential increase in the risk of nutrient loss,or agricultural non-point source pollution can be a tradeoff if the intensive practices are not managed appropriately. | CHEN Liding QI Xin ZHANG Xinyu LI Qi ZHANG Yanyan | 2011 | Chinese Geographical Science2011，21，4： | 5 |
| 14 | Analysis and assessment of heavy metal contamination in surface water and sediments: a case study from Luan River, Northern China显示文摘重金属 Cu, Ni, Pb, Zn, Cd,和 Cr 的集中从 Luan 河 inChina 在表面水和沉积里被检验,。与在 Cu 和 Ni 的衰落,集中在下游的车站在表面水里发现了。这发现建议水水流是在重金属污染的一个主要解释因素。在河的中间的活动范围观察的许多 Cr, Pb,和 Cd 在本地区域显示重金属污染,尽管 Daheiting 水库下游地在水里的集中有明显的减少。人为的活动贡献重金属污染沉积,这因此是的离开河更远的沉积也建议的在看见的 Cu , Pb ,和 Ni 的重要升起趋势用作环境指示物,与沉积,评价用geo累积索引被进行(我<潜水艇class=“ a-plus-plus ”> geo )和潜在的生态的风险索引( RI )。我 < 潜水艇 class= “ a-plus-plus ” > geo 价值揭示了那 Cd (3.13 ) , Cr (2.39 ) 在 Luan 河里显著地积累了。RI 珍视因为采样车站的大多数(89%) 比 300 高,建议来自 Luan 河的那沉积提出严重生态的风险,与在上面、中间的溪流的比那下游地高的潜在的生态的风险。在水里的 Pb/Ni 和在沉积的 Cr/Ni 之中的好关联被观察。簇分析建议 Cd 可以有各种各样的起源,从人为的来源被导出。 | Zhaoming WANG Ranhao SUN Haiping ZHANG Liding CHEN | 2015 | Frontiers of Environmental Science & Engineering2015，9，2： | 5 |
| 15 | The effects of land use on runoff and soil nutrient losses in a gully catchment of the hilly areas:implications for erosion control显示文摘Serious soilerosion is one ofthe majorissues threatening sustainable land use in semiarid areas,especially in the LoessPlateau ofChina.Understanding the effectsofland use on soiland water loss is important for sustainable land use strategy. Two sub-catchments: catchment A (CA) and catchment B (CB) with distinct land uses were selected to measure soil moisture,runoff and soil nutrientlossin Da Nangou catchmentofthe LoessPlateau ofChina.The effectsofland use patterns on runoffand nutrientlosseswere analyzed based on soilmoisture pattern by kriging and soilnutrients using multiple regression model.The resultsindicated thatthere were significantdifferencesin runoff yield and soil nutrient losses between the two sub-catchments. W ith similar land uses, the CA produced an average sediment yield of 49 kg ha-1 and 22.27 kg ha-1 during two storm events. M eanwhile,there was almostno runoffin the CB with dissimilarland uses during the same events. Bufferzonesshould be established to re-absorb runoffand to trap sedimentsin catchmentwith similar land use structure such as the CA.M oreover,land use managementstrategy aiming to increase the infiltration threshold ofhydrologicalresponse unitscould decrease the frequency ofrunoffoccurrence on aslopeand catchmentscale. | WANG Jun FU Bojie QIU Yang CHEN Liding CHEN Chen HU Baodong | 2005 | Journal of Geographical Sciences2005，15，4： | 3 |
| 16 | Landscape Network Approach to Assess Ecological Impacts of Road Projects on Biological Conservation显示文摘Awareness of the adverse ecological effects of road and other large construction projects has resulted in a rapidly growing demand to quantitatively predict and evaluate the effects on gene flow among plants and animals in natural habitats.In this study,we evaluated the effects of different road construction scenarios on animal species movement by using the methods of ecological landscape connectivity in the typical regions of Yunnan Province,China.The results showed landscape connectivity levels(Probability of Connectivity(PC))decreased after road construction and species with lower dispersal abilities were more affected to the subsequent habitat fragmentation.First level roads affected landscape connectivity most significantly.At a distance of 100 m,the PC index decreased more than 50%.Further analysis suggested that the use of landscape connectivity to assess landscape processes revealed the adverse effects on the species movement more effectively compared with the traditional landscape pattern analysis.In addition,we conducted a graph theory and a least-cost modeling discussion,it is obvious that they are powerful tools to represent and analyze landscape networks with respect to related species movement.Network analysis offers a quantitative and simple but effective tool for ecological process assessment and biological conservation on large scales. | LIU Shiliang DENG Li CHEN Liding LI Junran DONG Shikui ZHAO Haidi | 2014 | Chinese Geographical Science2014，24，1： | 3 |
| 17 | Soil Carbon Stock and Flux in Plantation Forest and Grassland Ecosystems in Loess Plateau, China显示文摘Carbon sequestration occurs when cultivated soils are re-vegetated. In the hilly area of the Loess Plateau, China, black locust(Robinia pseudoacacia) plantation forest and grassland were the two main vegetation types used to mitigate soil and water loss after cultivation abandonment. The purpose of this study was to compare the soil carbon stock and flux of these two types of vegetation which restored for 25 years. The experiment was conducted in Yangjuangou catchment in Yan′an City, Shaanxi Province, China. Two adjacent slopes were chosen for this study. Six sample sites were spaced every 35–45 m from summit to toe slope along the hill slope, and each sample site contained three sampling plots. Soil organic carbon and related physicochemical properties in the surface soil layer(0–10 cm and 10–20 cm) were measured based on soil sampling and laboratory analysis, and the soil carbon dioxide(CO2) emissions and environmental factors were measured in the same sample sites simultaneously. Results indicated that in general, a higher soil carbon stock was found in the black locust plantation forest than that in grassland throughout the hill slope. Meanwhile, significant differences in the soil carbon stock were observed between these two vegetation types in the upper slope at soil depth 0–10 cm and lower slope at soil depth 10–20 cm. The average daily values of the soil CO2 emissions were 1.27 μmol/(m2·s) and 1.39 μmol/(m2·s) for forest and grassland, respectively. The soil carbon flux in forest covered areas was higher in spring and less variation was detected between different seasons, while the highest carbon flux was found in grassland in summer, which was about three times higher than that in autumn and spring. From the carbon sequestration point of view, black locust plantation forest on hill slopes might be better than grassland because of a higher soil carbon stock and lower carbon flux. | HU Chanjuan LIU Guohua FU Bojie CHEN Liding LYU Yihe GUO Lei | 2014 | Chinese Geographical Science2014，24，4： | 2 |
| 18 | Spatial Scale Effects of Water Erosion Dynamics:Complexities, Variabilities, and Uncertainties显示文摘Severe water erosion is notorious for its harmful effects on land-water resources as well as local societies. The scale effects of water erosion, however, greatly exacerbate the difficulties of accurate erosion evaluation and hazard control in the real world. Analyzing the related scale issues is thus urgent for a better understanding of erosion variations as well as reducing such erosion. In this review article, water erosion dynamics across three spatial scales including plot, watershed, and regional scales were selected and discussed. For the study purposes and objectives, the advantages and disadvantages of these scales all demonstrate clear spatial-scale dependence. Plot scale studies are primarily focused on abundant data collection and mechanism discrimination of erosion generation, while watershed scale studies provide valuable information for watershed management and hazard control as well as the development of quantitatively distributed models. Regional studies concentrate more on large-scale erosion assessment, and serve policymakers and stakeholders in achieving the basis for regulatory policy for comprehensive land uses. The results of this study show that the driving forces and mechanisms of water erosion variations among the scales are quite different. As a result, several major aspects contributing to variations in water erosion across the scales are stressed: differences in the methodologies across various scales, different sink-source roles on water erosion processes, and diverse climatic zones and morphological regions. This variability becomes more complex in the context of accelerated global change. The changing climatic factors and earth surface features are considered the fourth key reason responsible for the increased variability of water erosion across spatial scales. | WEI Wei CHEN Liding YANG Lei FU Bojie SUN Ranhao | 2012 | Chinese Geographical Science2012，22，2： | 2 |
| 19 | Protein and RNA expression of acid-sensing ion channels 2 and 3 in myocardial ischemia rats induced by isoproterenol显示文摘OBJECTIVE:To investigate the impact of electro-acupuncture at the Neiguan(PC 6) acupoint on protein and RNA expression of acid-sensing ion channel 2(ASIC2) and ASIC3 in myocardial ischemia rats.METHODS:Fifty male Sprague-Dawley rats were used,weighing(230 ± 50) g.The rats were randomized into a normal group A,model group B,Neiguan(PC 6) group C,Lieque(LU 7) group D,and A-shi points group E.There were 10 rats in each group.Rats were continuously administered 85 mg/kg intravenous isoproterenol daily to establish the model.Successfully modeled rats in groups C,D,and E were given electro-acupuncture treatment.Each group of rats was sacrificed with chloral hydrate(1 mL/100 g) intraperitoneal injection.The left ventricular myocardium was extracted and placed at- 70 ℃ until use.Western blot analysis and real-time PCR were performed to assay protein and RNA expressions of ASIC2 and ASIC3,respectively.Fold changes in RNA expression were quantified with the 2~^(-△△Ct) method.Blood samples were drawn from the aorta abdominalis and tested for creatine kinase-MB(CK-MB) and lactate dehydrogenase(LDH) levels using enzyme-linked immunosorbent assay.RESULTS:Myocardial ischemia rats given electro-acupuncture at the Neiguan(PC 6) acupoint had significantly lower protein and RNA expression of ASIC2 and ASIC3,and CK-MB and LDH levels,compared with model rats(P < 0.01).CONCLUSION:Electro-acupuncture at the Neiguan(PC 6) acupoint can not only decrease the protein and RNA expression of ASIC2 and ASIC3,but also inhibit the opening of ASICs and reduce the cardiomyocyte damage in myocardial ischemia rats. | Wang Shudong Zhang Lide Dong Baoqiang Zhang Wenshun Ho Chin Ee Guo Na Chen Yiguo | 2015 | Journal of Traditional Chinese Medicine2015，35，2： | 2 |
| 20 | The effect of land cov- er/vegetation on soil water dynamic in the hilly area of the loess plateau, China显示文摘 | Chen Liding Huang Zhilin Gong Jie | 2007 | C atena2007，70，2： | 1 |
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