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Effects of Land Use Change on Eco-environment in Hilly Area of Central Sichuan Basin——A Case Study of Yanting County, Sichuan Province 被引量:2
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作者 Luo Huai-liang, Zhu Bo, Chen Guo-jie, Gao Mei-rongInstitute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, Sichuan, China College of Resources and Environment, Sichuan Normal University, Chengdu 610066, Sichuan, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03B期981-986,共6页
With the artificial alder and cypress mixed forest being planted, there has been a marked land use change since 1970s' in Hilly Area of Central Sichuan Basin, China. Data from meteorological observations or posts ... With the artificial alder and cypress mixed forest being planted, there has been a marked land use change since 1970s' in Hilly Area of Central Sichuan Basin, China. Data from meteorological observations or posts operated over long time, measurement and calculation of NPP (net primary production) and biomass of biological community, and analysis of soil organic matter content show that the artificial alder and cypress mixed forest has outstanding eco-environmental effect: adjusting local climate, raising soil fertility, alleviating menace of drought, and raising NPP and biomass of biological community. It is very beneficial for improving ecological environment to afforest artificial alder and cypress mixed forest in populous Hilly Area of Central Sichuan Basin, China. Key Words: land use/land cover change (LUCC); eco-environmental effect; Hilly Area of Central Sichuan Basin; the artificial alder and cypress mixed forest 展开更多
关键词 of as for Sichuan Province Effects of Land use Change on Eco-environment in Hilly area of Central Sichuan Basin A Case Study of Yanting County on ECO
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Mutual Conversion of Land Use between Urban and Rural Area in the Process of Urbanization: A Case Study of Shandong Province
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作者 Xu Hong College of Population, Resource and Environment, Shandong Normal University, Jinan Shandong 250014, China 《Chinese Journal of Population,Resources and Environment》 北大核心 2007年第2期93-96,共4页
Urbanization is one of the driving forces for the land use change in type and structure, and its prominent effect is to convert rural land to urban land. This paper takes Shan-dong Province as an example to analyze th... Urbanization is one of the driving forces for the land use change in type and structure, and its prominent effect is to convert rural land to urban land. This paper takes Shan-dong Province as an example to analyze the current situation of the mutual conversion between the urban and rural areas from the aspects of the structure of land use, the decreasing tendency of the cultivated land, the changes of land use in urban and rural residential areas. It points out that cultivated land is converted to residential area land, industrial and/or mining area land. The relationship between the urban area land and the cultivated land is more direct; meanwhile, the changes of rural residential area lag behind obviously. The decrease of the cultivated land and the decline of soil quality will be the two difficult problems in the process of urbanization. 展开更多
关键词 mutual conversion of land use between urban and rural areas structure of land use flow of the cultivated land
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Sarcopenia diagnosed using masseter muscle area predictive of early mortality following severe traumatic brain injury 被引量:1
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作者 Rindi Uhlich Parker Hu 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第12期2089-2090,共2页
Traumatic brain injury(TBI)represents a global pandemic and is currently a leading cause of injury related death worldwide.Unfortunately,those who survive initial injury often suffer devastating functional,social,an... Traumatic brain injury(TBI)represents a global pandemic and is currently a leading cause of injury related death worldwide.Unfortunately,those who survive initial injury often suffer devastating functional,social,and economic consequences. 展开更多
关键词 TBI Sarcopenia diagnosed using masseter muscle area predictive of early mortality following severe traumatic brain injury
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Changes in soil organic carbon and nitrogen after 26 years of farmland management on the Loess Plateau of China 被引量:10
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作者 ZHOU Zhengchao ZHANG Xiaoyan GAN Zhuoting 《Journal of Arid Land》 SCIE CSCD 2015年第6期806-813,共8页
Soil carbon(C) and nitrogen(N) play a crucial role in determining the soil and environmental quality. In this study, we investigated the effects of 26 years(from 1984 to 2010) of farmland management on soil orga... Soil carbon(C) and nitrogen(N) play a crucial role in determining the soil and environmental quality. In this study, we investigated the effects of 26 years(from 1984 to 2010) of farmland management on soil organic carbon(SOC) and soil N in abandoned, wheat(Triticum aestivum L.) non-fertilized, wheat fertilized(mineral fertilizer and organic manure) and alfalfa(Medicago Sativa L.) non-fertilized treatments in a semi-arid region of the Loess Plateau, China. Our results showed that SOC and soil total N contents in the 0–20 cm soil layer increased by 4.29(24.4%) and 1.39 Mg/hm2(100%), respectively, after the conversion of farmland to alfalfa land. Compared to the wheat non-fertilized treatment, SOC and soil total N contents in the 0–20 cm soil layer increased by 4.64(26.4%) and 1.18 Mg/hm2(85.5%), respectively, in the wheat fertilized treatment. In addition, we found that the extents of changes in SOC, soil total N and mineral N depended on soil depth were greater in the upper soil layer(0–30 cm) than in the deeper soil layer(30–100 cm) in the alfalfa land or fertilizer-applied wheat land. Fertilizer applied to winter wheat could increase the accumulation rates of SOC and soil total N. SOC concentration had a significant positive correlation with soil total N concentration. Therefore, this study suggested that farmland management, e.g. the conversion of farmland to alfalfa forage land and fertilizer application, could promote the sequestrations of C and N in soils in semi-arid regions. 展开更多
关键词 soil organic carbon(SOC) soil N fertilizer land use change semi-arid area
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Water Erosion in the Donga Soils in Subhumid Zone in West Africa
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作者 Julien Avakoudjo Félix Alladassi Kouelo +5 位作者 Valentin Missiako Kindomihou Pierre Irénikatché Akponikpe Anastase Hessou Azontonde Brice Augustin Sinsin Tobi Moriaque Akplo Mahugnon Socrate Agonvinon 《Journal of Environmental Protection》 2020年第12期1073-1088,共16页
The runoff and soil loss were assessed <em>in situ</em> at the scale of 2.12 m<sup>2</sup> plots during the rainy season of 2010 to better understand the determinants and magnitude of the massi... The runoff and soil loss were assessed <em>in situ</em> at the scale of 2.12 m<sup>2</sup> plots during the rainy season of 2010 to better understand the determinants and magnitude of the massive soil loss and land subsidence (donga) in the sub-humid zone of Africa in Karimama, North Benin. The experimental design was a split plot with two factors: the topography in 3 modalities (upstream, center and downstream of the donga) was assigned as main plot factor and the degree of degradation of dongas in 2 modalities (beginner dongas and advanced dongas) was assigned as subplot factor. Runoff water was collected through a storage system composed of two tanks. Data were collected on 36 plots (9 plots per donga × 4 dongas). The runoff varies significantly from one site to another for the rainy episode of October 10, 2010. It is twice as high in land use areas (5.87 mm) as in W Park (2.32 mm;l.s.d. = 1.81 mm). From upstream to downstream, runoff and soil loss increased from 2.4 mm to 85.3 mm and 80 g<span style="white-space:nowrap;">·</span>m<sup>-2</sup> to 197 g<span style="white-space:nowrap;">·</span>m<sup>-2</sup>, respectively. Runoff is high in the early dongas (7.60 mm) and low in the advanced dongas (5.68 mm) in contrast to lower soil loss in the early dongas (34 g<span style="white-space:nowrap;">·</span>m<sup>-2</sup>) and high in the advanced dongas (237 g<span style="white-space:nowrap;">·</span>m<sup>-2</sup>). The low value of soil loss with respect to the magnitude of the phenomenon suggests the probable occurrence of other soil loss mechanisms to be elucidated. 展开更多
关键词 W National Park Land use areas Dongas RUNOFF EROSION Soil Loss
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界定土地利用面积值并优化其结构以改善生态系统服务供需平衡状态
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作者 黄佩 赵筱青 +8 位作者 普军伟 顾泽贤 冉玉菊 徐逸飞 吴倍昊 董雯雯 瞿国寻 熊波 周龙进 《Journal of Geographical Sciences》 SCIE CSCD 2024年第5期891-920,共30页
Improving the supply-demand balance of ecosystem services(SDBES)from the perspective of land use is essential for managing regional ecosystem and realizing sustainable development.By combining land use with the supply... Improving the supply-demand balance of ecosystem services(SDBES)from the perspective of land use is essential for managing regional ecosystem and realizing sustainable development.By combining land use with the supply and demand of ecosystem services(SDES),a technical framework for defining land use threshold and optimizing its structure to improve the SDBES state was constructed and applied to a practical case.The spatial pattern of supply and demand of each ES in Lancang county was distinctly heterogeneous,with sig-nificant differences in SDES across different land use types.Strong spatial heterogeneity ex-isted in the ESDR of each ES at the grid scale,and the areas of deficit were ranked as carbon sequestration>water conservation>habitat quality>food production.The structure of dry land,paddy field,tea,evergreen broad-leaved forest,grassland,urban construction land,and indus-trial and mining construction land were the focus of land use optimization.Based on the land use area thresholds under the SDBES,the optimal land use structure for maximizing compre-hensive benefits contributed to a balanced relationship between SDES and promoted sustain-able regional development.The study provides a new perspective and method for improving the SDBES state,alleviating land conflicts,and managing ecological environment. 展开更多
关键词 ecosystem services supply-demand balance ecological supply-demand ratio land use area threshold landuse structureoptimization
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Reconstruction of Lu-level cropland areas in the Northern Song Dynasty (AD976-1078) 被引量:4
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作者 何凡能 李美娇 李士成 《Journal of Geographical Sciences》 SCIE CSCD 2017年第5期606-618,共13页
Based on data on taxed-cropland area and on the number of households in historical documents, a probabilistic model of cropland distribution and a cropland area allocation model were designed and validated. Cropland a... Based on data on taxed-cropland area and on the number of households in historical documents, a probabilistic model of cropland distribution and a cropland area allocation model were designed and validated. Cropland areas for the years AD976, 997, 1066, and 1078 were estimated at the level of Lu(an administrative region of the Northern Song Dynasty). The results indicated that(1) the cropland area of the whole study region for AD976, 997, 1066, and 1078 was about 468.27 million mu(a Chinese unit of area, with1 mu=666.7m2), 495.53 million mu, 697.65 million mu, and 731.94 million mu, respectively. The fractional cropland area(FCA) increased from 10.7% to 16.8%, and the per capita cropland area decreased from 15.7 mu to 8.4 mu.(2) With regard to the cropland spatial pattern, the FCA of the southeast, north, and southwest regions of the Northern Song territory increased by 12.0%, 5.2%, and 1.2%, respectively. The FCA of some regions in the Yangtze River Plain increased to greater than 40%, and the FCA of the North China Plain increased to greater than 20%. However, the FCA of the southwest region(except for the Chengdu Plain) in the Northern Song territory was less than 6%.(3) There were 84.2% Lus whose absolute relative error was smaller than 20% in the mid Northern Song Dynasty. The validation results indicate that our models are reasonable and that the results of reconstruction are credible. 展开更多
关键词 land use/cover change cropland area Lu-level reconstruction spatial–temporal characteristics Northern Song Dynasty
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Comparative Study on Temporary Shelter Planning After Earthquake: With the Plate-Houses Construction After Wenchuan Earthquake as an Example
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作者 Ni Feng Qian Fang(译) Tang Yan(校) 《China City Planning Review》 CSCD 2017年第3期50-57,共8页
After the Wenchuan earthquake of 2008 in Sichuan, China, in order to meet the demand for temporary and transitional houses, Chinese government organized the construction of a great number of plate-houses that played a... After the Wenchuan earthquake of 2008 in Sichuan, China, in order to meet the demand for temporary and transitional houses, Chinese government organized the construction of a great number of plate-houses that played an important role at the time. This paper conducts a comparative study between the plate-houses constructed after Wenchuan earthquake and the temporary shelters in other countries on aspects including planning layout, area index, social psychology, economic cost, etc. In the Wenchuan case, statistics show that the FAR of the plate-house residential area is around 0.4, the number of supporting houses makes up 20% in the total house sets, the average floor area of each house is about 25 m^2 that occupies a land area of 60 m^2, and the per capita planned floor area is 7 m^2, which is far above the international recommended minimum standard of 3.5 m^2. Even if the area for residence, school, hospital, and other land use functions are all counted, the per capita planed land use area of China's plate-house area is still above the international recommended minimum standard, which is 30 m^2. This paper holds that China has been capable of the planning and construction of the physical space of plate-house, but the holistic concept and the systematic arrangement level still need further promotion. 展开更多
关键词 WENCHUAN EARTHQUAKE temporary and transitional settlement house plate-house FAR(floor area ratio) per capita floor area per capita land use area
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4 × 25 GHz uni-traveling carrier photodiode arrays monolithic with In P-based AWG demultiplexers using the selective area growth technique
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作者 叶焓 韩勤 +5 位作者 吕倩倩 潘盼 安俊明 杨晓红 王玉冰 刘荣瑞 《Chinese Optics Letters》 SCIE EI CAS CSCD 2017年第8期90-94,共5页
InP-based photonics integration is becoming a competi- tive candidate for realizing optical modules with enhanced functionality at a reduced cost, especially in optical com- munication systems, since the proposal of w... InP-based photonics integration is becoming a competi- tive candidate for realizing optical modules with enhanced functionality at a reduced cost, especially in optical com- munication systems, since the proposal of wavelength division multiplexing (WDM). In recent years, network traffic has raised demands for high capacity, high speed transmission systems. 展开更多
关键词 AWG In GHz uni-traveling carrier photodiode arrays monolithic with In P-based AWG demultiplexers using the selective area growth techni area
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