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Effects of Combined Application of Water Retaining Agents and Organic Materials on Water Holding Characteristics of Yellow Brown Soils in Hilly Areas 被引量:1
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作者 唐玉邦 虞利俊 +4 位作者 徐磊 罗佳 王东升 范如芹 裴勤 《Agricultural Science & Technology》 CAS 2015年第9期1985-1988,共4页
[Objective] The aim was to reduce fertilizer and water losses caused by surface runoffs in rainy season and provide scientific references for soil moisture in arid season. [Method] The application proportion of comple... [Objective] The aim was to reduce fertilizer and water losses caused by surface runoffs in rainy season and provide scientific references for soil moisture in arid season. [Method] The application proportion of complex water-holding organic materials was determined by multi-factor mixture experiment and the curve changes of soil moisture characters were tested to analyze water-holding capacity and water availability of soils. [Result] The initial moisture content of soil with different mixture proportions improved in varying degrees. For example, when water-retention agents reached 0.4% and 0.6% of soil weight, soil moisture contents were 69.0% and70.5%, respectively, which showed significant differences with the control(S0.0). Soil dehydration terms in different treatments all extended, prolonging in the range of4.6-14 d. [Conclusion] The applications of water-retention agent and organic material would improve water-holding capacity of hills and low mountains, and initial moisture content and dehydration cycle tend to be volatile upon mixture proportion. Therefore,it is necessary to adjust soil fertility, crop species, and irrigation to meet crop demands on fertilizer and water. 展开更多
关键词 Water retaining agents Organic materials Soils of hilly areas Water characteristics
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Mechanism of formation of sliding ground fissure in loess hilly areas caused by underground mining 被引量:10
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作者 Liu Hui Deng Kazhong +1 位作者 Lei Shaogang Bian Zhengfu 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第4期553-558,共6页
Based on a shallow-buried coal seam covered with thick loose layers in hilly loess areas of western China,we developed a mechanical model for a mining slope with slope stability analysis, and studied the mechanism of ... Based on a shallow-buried coal seam covered with thick loose layers in hilly loess areas of western China,we developed a mechanical model for a mining slope with slope stability analysis, and studied the mechanism of formation and development of a sliding ground fissure by the circular sliding slice method.Moreover, we established a prediction model of a sliding fissure based on a mechanical mechanism,and verified its reliability on face 52,304, an engineering example, situated at Daliuta coal mine of Shendong mining area in western China. The results show that the stress state of a mining slope is changed by its gravity and additional stress from the shallow-buried coal seam and gully terrain. The mining slope is found to be most unstable when the ratio of the down-sliding to anti-sliding force is the maximum, causing local fractures and sliding fissures. The predicted angles for the sliding fissure of face 52,304 on both sides of the slope are found to be 64.2° and 82.4°, which are in agreement with the experimental data. 展开更多
关键词 Loess hilly area Sliding ground fissure Mechanical model Landslide stability Circular sliding Slice method
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Changes of hydrochemical composition and heavy metals concentration in shallow groundwater from karst hilly areas in Guiyang region,China 被引量:2
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作者 刘方 刘丛强 +1 位作者 赵杨 李准 《Journal of Central South University》 SCIE EI CAS 2010年第6期1216-1222,共7页
The quality changes of shallow groundwater from karst hilly areas in Guiyang region of China impacted by the urbanization were investigated. The results show that the major ions in shallow groundwater from the karst h... The quality changes of shallow groundwater from karst hilly areas in Guiyang region of China impacted by the urbanization were investigated. The results show that the major ions in shallow groundwater from the karst hilly areas are mainly composed of HCO3^-, SO4^2-, Ca^2+ and Mg^2+, and the concentrations scopes of NO3^-, Cl^-, K^+ and Na^+ of the groundwater in agricultural, residential and industrial areas are 4.5-9.6, 2.8-7.1, 3.9-6.3 and 2.5-4.9 times higher than those in the forest areas, respectively. The concentrations of As, Pb and Cd of shallow groundwater in the industrial areas are also significantly enhanced, followed by those in the residential areas and the agricultural areas. The concentrations of NO3^-, SO4^2- , As, Pb and Cd of the groundwater in the industrial areas and those of NO3^- , SO4^2-, As and Cd of shallow groundwater in the residential areas reach grade Ⅲ of the Groundwater Quality Standard of China (GB/T 14848-93), while the concentration of NO3^- in the groundwater from the industrial areas exceeds grade V. With the process of urbanization, NO3^- is the key factor to influence the groundwater quality in karst hilly areas, followed by SO4^2-, As, Pb and Cd. 展开更多
关键词 karst hilly areas shallow groundwater URBANIZATION heavy metals Guiyang
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Potato yield gaps across the rainfed Yin-mountain Hilly Area of China 被引量:2
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作者 JIA Li-guo CHEN Yang +4 位作者 QIN Yong-lin LIANG Rui-fang CUl Shi-xin MA Zhong FAN Ming-shou 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第11期2418-2425,共8页
Yin-mountain Hilly Area is one of the ideal regions for potato (Solanum tuberosum) production in China. However, potato yield is severely limited as a result of rain-fed crop mode due to water deficiency, as well as... Yin-mountain Hilly Area is one of the ideal regions for potato (Solanum tuberosum) production in China. However, potato yield is severely limited as a result of rain-fed crop mode due to water deficiency, as well as an inadequate farming practices. In this study, yield gaps were determined by using attainable yield (Ya) as a benchmark under optimized management practices, i.e., micro-ridge and side planting with plastic-mulching (MS), and flat planting with plastic-mulching (PM). The yields under MS and PM modes are defined as Yal and Ya2, respectively. Under the same field with MS and PM modes but different densities and fertilizer usages and so on, it was defined as simulated farmers' practices. The yield of simulated farmers' practices (Yfl) reached 57.3 and 69.6% of Yal and Ya2, respectively, while the average yield of 298 randomly surveyed farmers (Yf2) reached only 37.0 and 47.8% of Yal and Ya2 for rain-fed potato, respectively. The gaps of water use efficiency exhibited similar pattern. Further analysis shows that improper measures in rainwater conservation and accumulation, and other management practices contributed to 18.5, 18.2, and 42.6% of yield gap between Yal and Yf2. Improper nutrition management, including overuse of nitrogen and the deficiency of phosphorus andpotassium supplication, was one of the important reasons of yield gap. The results indicate the possibilities of increasing rain-fed potato yields by optimized water and fertilizermanagements in the Yin-mountain Hilly Area. 展开更多
关键词 rain-fed POTATO yield gap water management Yin-mountain hilly area
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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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The Effects of Land Uses on Purplish Soil Erosion in Hilly Area of Sichuan Province,China 被引量:1
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作者 ZHAHGJianhui TLANGuanglong WEIChaofu 《Journal of Mountain Science》 SCIE CSCD 2005年第1期68-75,共8页
In order to evaluate the soil erosion rate for different land uses and make recommendations on land-use alternatives for erosion control in hilly and mountain areas on a Purplish soil (Regosols in FAO taxonomy), exper... In order to evaluate the soil erosion rate for different land uses and make recommendations on land-use alternatives for erosion control in hilly and mountain areas on a Purplish soil (Regosols in FAO taxonomy), experimental data were obtained from three continuously monitored sites located at Yanting, Nanbu and Pengxi of Sichuan province. The data showed that the rank of erosion rate is farmland > unfenced grassland > fenced grassland > forestland. The erosion rate of farmland was more than 3 times higher than that of forestland and fenced grassland, indicating that restricting human activity is crucial for over-erosion. The erodibility was higher at the initial period of rainy season for all the three types of land use. The erosion rates of fenced grassland and mature afforestation land were not proportional to rainfall intensity because these land uses changed impact energy of the rainfall. This research showed that restricting human activity, intensifying the management of initial period of rainy season, and increasing the cover rate of land surface are the three major measures for soil erosion prevention. It is recommended that farmers should cease cultivation on farmland at the top of hills and steep slope land return those lands back to grassland or forestland. 展开更多
关键词 Soil erosion land use hilly area purplish soil
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Spatial and Temporal Distributions of Soil Organic Matter in the Mixed Plantations of Alder and Cypress in the Hilly Areas of Central Sichuan Basin
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作者 WU Pengfei ZHU BO +1 位作者 YANG Yuanli WANG Xiaoguo 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期1021-1027,共7页
The investigation was conducted on the spatial and temporal distributions of soil organic mater (SOM) in the mixed plantations of alder (Aluns crernastogyne) and cypress (Cupressus funebris ) (MPAC), which dis... The investigation was conducted on the spatial and temporal distributions of soil organic mater (SOM) in the mixed plantations of alder (Aluns crernastogyne) and cypress (Cupressus funebris ) (MPAC), which distributed in the hilly areas of central Sichuan Basin (HACSB). The results show that: (1) the spatial distribution of SOM among different sites at the same age are not significant before 15-year-old, but significant at 20-year-old, and not significant again after 25-year-old; (2) the SOM contents in 0-15 cm and 15-30 cm layers increase sharply from 10- to 15-year-old, and decline gradually from 15- to 30- year-old; the SOM contents of the 30-year-old PCP were 80. 38% and 78.42% higher than that of the 10-year-old, but 29.16% and 53.37% lower than that of 15-year-old in the 0-15 cm and 15-30 cm layers, respectively. The decrease of SOM contents would lead to the degradation of soil fertility and the decline of forest productivity. 展开更多
关键词 hilly areas of central Sichuan mixed plantations of alder and cypress soil organic matter spatial distributions temporal dynamics
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Characteristics of Soil Seed Banks of Typical Plant Communities in Hilly Area of Funiu Mountain
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作者 Yanjiao LI Pengsen CAI +3 位作者 Weishuang TONG Huashan GAO Yan ZHAO Limin WANG 《Asian Agricultural Research》 2020年第11期27-33,共7页
[Objectives]The purpose was to investigate the characteristics of soil seed bank of typical plant communities in hilly area of Funiu Mountain.[Methods]The seed density,number of species and species composition of the ... [Objectives]The purpose was to investigate the characteristics of soil seed bank of typical plant communities in hilly area of Funiu Mountain.[Methods]The seed density,number of species and species composition of the soil seed bank of typical plant communities such as Themeda japonica,Imperata cylindrica,Vitex negundo,Quercus acutissima,Robinia pseudoacacia,Platycladus orientalis and Populus canadensis in the surface,top 0-5 and top 5-10 cm soil were studied.[Results]The seed reserves of plant communities at different succession stages were(220.00±95.39)–(2650.00±1064.52)seeds/m2.A total of 48 species were counted in the seed bank,belonging to 45 genera in 22 families.Total 27 species were identified in the above-ground vegetation,belonging to 25 genera in 14 families.In the shallow soil where the seeds gathered,the seed densities of Imperata cylindrica and Themeda japonica were relatively low.The reserves of plant communities with different naturalness degrees were(403.33±64.29)-(2110.00±356.79)seeds/m2.A total of 67 species were counted in the seed bank,belonging to 64 genera in 37 families.A total of 45 species were identified in the above-ground vegetation,belonging to 43 genera in 28 families.In the soil layers of 0-5 and 5-10 cm,the seed density of natural secondary Q.acutissima was higher than those of planted P.canadensis,P.orientalis and R.pseudoacacia.In each soil layer,the species number of natural secondary Q.acutissima forest was slightly smaller than those of planted P.canadensis,P.orientalis and R.pseudoacacia forests.[Conclusions]The seeds in the soil seed bank may not completely come from existing above-ground vegetation.Manual assistance is required for vegetation restoration or reconstruction relying on soil seed bank,to ensure the direction of community succession. 展开更多
关键词 Soil seed bank Seed density Species number Species composition hilly area Funiu Mountain
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Path for the “Interaction between Industrialization and Urbanization” in Low Hilly Areas of Sichuan Against the Background of New Urbanization: A Case Study of Overall Planning of Lianjie Town in Weiyuan County
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作者 CHEN Shaoqing 《Journal of Landscape Research》 2015年第6期26-30,共5页
Taking the practical experience of Lianjie Town, Weiyuan County for example, this paper analyzed regional characteristics of the low hilly areas in Sichuan and interaction mechanism of "industrialization and urba... Taking the practical experience of Lianjie Town, Weiyuan County for example, this paper analyzed regional characteristics of the low hilly areas in Sichuan and interaction mechanism of "industrialization and urbanization", explored the path for the interaction between industrialization and urbanization from 5 perspectives, namely accelerating industrial upgrading, optimizing industrial structure, breaking through the dual system, industry back-feeding town, and protecting ecological background. 展开更多
关键词 Interaction between industrialization and urbanization Integration of industry and city Low hilly area
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Moderate scale and realization potential of new citrus-planting business entities in hilly and mountainous areas in China
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作者 ZHANG Xuan-yun ZHANG Shi-chao +3 位作者 LIU Jing-yu RAN Na ZHANG Xiang NING Qi-wen 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2315-2343,共29页
The natural and economic conditions of agricultural resources vary greatly in China,especially in hilly and mountainous areas.The phenomenon of land fragmentation has become increasingly prominent,so that large-scale ... The natural and economic conditions of agricultural resources vary greatly in China,especially in hilly and mountainous areas.The phenomenon of land fragmentation has become increasingly prominent,so that large-scale operations cannot be fully achieved in a short period of time,and the centralized and continuous scale of operations cannot be realized in China.In addition,with increasingly strict farmland protection and agricultural land use control systems,the issues of nongrain production and nonagricultural cultivated land use have become increasingly restricted.Thus,it is quite necessary to determine the appropriate scale of operations and the means to achieve moderately scaled operations for the new business entities.On the basis of microsurvey data for 108 new citrus-planting business entities in the modern agricultural park in the Chongqing's Jiangjin District,an area with long citrus-planting history,we measured the moderate scale of new citrus-planting business entities to maximize profit using a translog growth model.According to the projection pursuit model,we evaluated the suitability conditions of citrus planting in garden land,woodland,grassland,and general cultivated land in the study area.We then explored the potential for new moderate-scale business entities within different farming radii.The results showed that large-scale planting conditions of citrus in garden land,forest land,grassland,and general cultivated land in the study area were suitable,and the proportion of high-suitable and mediumsuitable land was 73.42%.Under the existing social and economic conditions,the moderate scale of new citrus-planting business entities in the study area was 1.8–2.7 hm^(2).In particular,its rankings from large to small were agricultural enterprises(17.19–25.78 hm^(2)),farmer cooperatives(16.88–25.33 hm^(2)),big growers and breeders(6.39–9.59 hm^(2)),and family farms(5.02–7.53 hm^(2)).In the sample of 108 households,only 47.22%of the entities achieved moderate-scale operation,of which 25%of the entities achieved a scale greater than moderate operation.However,52.78%of the entities achieved a scale of less than moderate operation.These entities would have to transfer the surrounding adjacent garden land,forest land,grassland,or general cultivated land to achieve largescale land management.The land area of the adjacent gardens in a 1000 m farming radius could meet the moderate-scale operation demand of the vast majority of new business entities.For the vast majority of new business entities,the land area of the adjacent woodland,grassland,and general cultivated land could supplement the garden land to achieve moderate-scale operation in a 500 m farming radius.If the land area with moderate suitability and high suitability is prioritized,the land area in the adjacent gardens in the 1000 m farming radius could meet the moderate-scale operation demand for the vast majority of new business entities.Within the 500 m farming radius,the vast majority of new business entities have achieved moderate-scale operations if the land area adjacent to forest land,grassland,and general arable land was supplemented by gardens;however,a few entities could not achieve moderate-scale operations.From the village perspective,gardens were prioritized.Sixteen villages had planting areas and planting suitability that exceeded the average level of the study area,accounting for 23.53%.If combined with the reserve potential of the garden land,eight villages could improve their potential,accounting for 11.76%.Therefore,the conditions of large-scale citrus planting in the study area should be further improved,and the scale expansion of new citrus-planting business entities should receive additional scientific guidance. 展开更多
关键词 Land management hilly and mountainous areas Agricultural business entities Moderate operation scale Agricultural land resources Realizing potential
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Structure and governance model of rural social space quality:A case study of Longxi County in the Loess Hilly Area of China 被引量:5
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作者 WU Shanshan MA Libang +1 位作者 TAO Tianmin DOU Haojian 《Journal of Geographical Sciences》 SCIE CSCD 2022年第7期1297-1320,共24页
The rural social space quality is an important indicator to measure the living standard and thinking ideas and so forth of rural residents in a certain region.In this paper,213 administrative villages in Longxi County... The rural social space quality is an important indicator to measure the living standard and thinking ideas and so forth of rural residents in a certain region.In this paper,213 administrative villages in Longxi County of the Loess Hilly Area,China are taken as evaluation units to construct the evaluation model of the rural social space quality.This paper deeply analyzed the variation patterns and their formation mechanism of the rural social space quality at a village scale,and proposed a governance model based on the rural social space quality.The results show that:(1)the social space quality levels of individual administrative villages show a gradually decreasing trend from the township seats to outward.The eastern part of Longxi County has a relatively high education level and living standard,and the western part has a relatively high population stability level and income level.(2)The rural social space quality is mainly in a ring structure,supplemented by the interlaced structure.The core area is the towns and their surrounding areas,while the transition area,marginal area,and other areas are expanded around the core area.(3)Social forces and spatial effects jointly shape the variation of the rural social space quality.Social organizations provide a driving force for the allocation of elements,and interweaving with the spatial effects lead to the differences in the social space quality.(4)The governance models of the rural social space quality are constructed based on the principles of retaining the rural“people”,optimizing the rural“land”,and developing the rural“industry”,so as to improve the rural centripetal force,core force,inner thrust,and source power. 展开更多
关键词 rural social space quality spatial structure formation mechanism governance model Longxi County in the Loess hilly area of China
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Current Situation and Influencing Factors of Pluriactivity in Mountainous and Hilly Rural Areas of Sichuan Province,China 被引量:4
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作者 LIU Shao-quan ZHANG Hai-qin +1 位作者 XIE Fang-ting GUO Shi-li 《Journal of Mountain Science》 SCIE CSCD 2013年第3期445-454,共10页
In this study, the current situation of pluriactivity in mountainous and hilly rural areas of Sichuan province was analyzed using representative sample survey data and natural factor data calculated based on 30 m-reso... In this study, the current situation of pluriactivity in mountainous and hilly rural areas of Sichuan province was analyzed using representative sample survey data and natural factor data calculated based on 30 m-resolution DEM and GIS. Moreover, using logistic regression model, a quantitative analysis was conducted on factors influencing pluriactivity in terms of individuals, households, communities and natural environmental conditions. The results showed that, (1) only 17.77% of rural laborers in mountainous and hilly areas of Sichuan province were engaged in pluriactivity. Geographically, pluriactivity was mainly chosen according to the "proximity principle", and was concentrated in construction and service industries; (2) the following factors have a significant influence on whether rural laborers in hilly areas engage in pluriactivity: gender, number of years of education, marriage, number of laborers and time to towns. Those with little influence include: age, health, family size, arable land per capita and per capita income, whether there are elderly people over 75 years and children less than 3 years. According to the main factors affecting pluriaetivity, the government should enhance vocational skills training for rural laborers in mountainous and hilly areas, especially for female laborers, further improve transport accessibility and encourage rural laborers, especially female laborers to move into pluriactivity to increase the income of farm households. 展开更多
关键词 Mountainous and hilly areas Rurallaborers Pluriaetivity Influencing factors
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Temporal variation of soil water and its influencing factors in hilly area of Chongqing,China 被引量:1
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作者 Zhong Shouqin Zhang Weihua +1 位作者 Lv Jiake Wei Chaofu 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2014年第4期47-59,共13页
The paper studied the temporal variation of soil water content and its influencing factors in hilly area of Chongqing by the yearly data of 2006 and 2007.According to precipitation anomaly percentage,the year 2006 was... The paper studied the temporal variation of soil water content and its influencing factors in hilly area of Chongqing by the yearly data of 2006 and 2007.According to precipitation anomaly percentage,the year 2006 was a dry year and 2007 a normal year.In the dry year 2006,the variations of soil moisture in all three layers(0-10 cm,10-20 cm,20-40 cm)were medium(10%<CV<30%);in the normal year 2007,the variation in the layer of 0-10 cm was strong(CV>30%),and those of the two deeper layers were weak(CV<10%).Hence,the seasonal variation of soil moisture in the humid area was large in the dry year and small in the wet year.The probability distributions of soil moisture in all three layers in both dry and normal years showed single-peak shapes.However,peak locations and values varied with different layers and years.Among factors affecting the temporal variation of soil moisture in the 0-10 cm layer,during March to May,the meteorological factors including temperature,sunshine and precipitation were all inversely correlated with soil water content variation.The correlations with average temperature and accumulated temperature were both highly significant P<0.01(P=0.00).The inverse correlations with sunshine and precipitation were significant P<0.05(P=0.01).Among soil physical properties,except for bulk density which was inversely correlated with soil moisture,all other properties were positively correlated.Organic material was positively correlated with soil moisture,which suggested that organics had the sponge effect and contributed to soil water storage and movement.During the period of June to September,there was no significant correlation between soil water content and total storage.The meteorological factors of temperature,accumulated temperature and sunshine were all inversely and highly significantly correlated with soil water content P<0.01(P=0.00). 展开更多
关键词 soil water temporal variation influencing factors hilly area
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The characteristics of gully erosion over rolling hilly black soil areas of Northeast China 被引量:6
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作者 胡刚 伍永秋 +3 位作者 刘宝元 张永光 游智敏 于章涛 《Journal of Geographical Sciences》 SCIE CSCD 2009年第3期309-320,共12页
In this study,short-term gully retreat was monitored from the active gullies selected in representative black soil area,using differential global positioning system(GPS).With the support of geographic information syst... In this study,short-term gully retreat was monitored from the active gullies selected in representative black soil area,using differential global positioning system(GPS).With the support of geographic information system(GIS),multi-temporal digital elevation models(DEM) were constructed from the data collected by GPS and used for further analysis.Based on the analysis of multi-temporal DEM,we discussed the erosion-deposition characteristics within gully and a developing model for black soil gully area of Northeast China was proposed.The results are:(1) The analysis of the monitored gully data in 2004 indicated that the retreat of gully head reached more than 10 m,gully area extended 170-400 m2,net gully eroded volume 220-320 m3,and gully erosion modulus 2200-4800 t?km?2?a?1.(2) Compared with the mature gully the initial gully grows rapidly,and its erosion parameters are relatively large.The erosion parameters have not only to do with flow energy,but also with the growth phase.(3) There are significant seasonal differences in gully erosion parameters.The extension of gully area and width dominates in winter and spring without marked net erosion while changes mainly occur in gully head and net erosion in rainy season.(4) It is remarkable for freeze-thaw erosion in the black soil area of NE China.The gully wall of SG2 extended 0.45 m under freeze-thaw effect in 2004,and the distance of gully head retreated maximally 6.4 m.(5) Due to freeze-thaw action and snowmelt,gully is primarily in the interior adjustment process in winter and early spring.There are much more depositions compared with that during rainy season,which can almost happen throughout the gully,while erosion mostly occurs near head,esp.for gullies having a relatively long history of development.On the other hand,the process of energy exchange with exterior dominates in rainy season.It is considered that this cyclic process is an important mechanism for gully growth in high latitude or/and high attitude regions. 展开更多
关键词 rolling hilly black soil areas gully erosion digital terrain model global positioning system
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Distribution of Soil Nutrients in Arable Land of Tropical Hilly and Mountainous Area
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作者 刘存法 王汀忠 《Agricultural Science & Technology》 CAS 2016年第7期1648-1650,1653,共4页
[Objective] The aim was to explore spatial distribution characters of soil nutrients in arable lands of Hainan mountainous areas and provide references for soil nutrient management in tropical mountainous areas. [Meth... [Objective] The aim was to explore spatial distribution characters of soil nutrients in arable lands of Hainan mountainous areas and provide references for soil nutrient management in tropical mountainous areas. [Method] The research took arable lands in Wuzhishan City as an example by field survey, sampling and lab analysis and investigated soil nutrients and distributions based on analysis of soil nutrient contents. [Result] The soils were dominated by acid soils, with pH of 5.1; soil nutrients were distributed in a non-uniform manner; contents of soil organic matter, available phosphorus, available potassium, as well as medium elements kept lower or moderate levels; effective copper and available zinc were rich. Local spe- cial climate, uneven distribution of parent material and non-uniform fertilization con- tributed to acid soils and unbalanced distribution of soil nutrients in Wuzhishan. [Conclusion] It is recommended to facilitate soil nutrient balance by promoting re- turning straws to farmlands and technical specification of balanced fertilization by soil testing as per nutrient distribution of arable lands in Wuzhishan City. 展开更多
关键词 Tropical area Arable land Soil nutrients hilly and mountainous area
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Impacts of Sloping Land Conversion Program on the vegetation in loess hilly and gully area of northern Shaanxi 被引量:3
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作者 Ma Junfei Lu Changhe Yu Bohua 《Ecological Economy》 2009年第2期160-167,共8页
Aiming at alleviating the serious soil erosion, the Chinese government initiated the Sloping Land Conversion Program (SLCP) in 1999. Now; after 8 years of project implementation, the ecological recovery effects of t... Aiming at alleviating the serious soil erosion, the Chinese government initiated the Sloping Land Conversion Program (SLCP) in 1999. Now; after 8 years of project implementation, the ecological recovery effects of the SLCP have become the hot issue of academic circle. This paper; raking the loess hill and gully area of northern Shaanxi as an example, presents a methodology for assessing the vegetation restoration effect of SLCP with normalized difference vegetation index (NDVI). The key components include calculation of the Growing Season NDVI (GSNDVI), and estimation of the NVDI change induced by climate and SLCP, respectively. Based on the method, the NDVI change between 2000 and 2006 was obtained using the GSNDVI that excluded the noise from snow and ice. After the part of total NDVI change caused to: climate variation was estimated using empiric formulae, we obtained the part induced by human factors, i.e. the SLCP The human induced part of ND VI change was considered as an approximation indicating the effect of the SLCP on the vegetation. Finally, we analyzed the ND VI change characters of the whole study area, different slope lands and different land use types by spatial statistics method. Results show that the vegetation condition is significantly improved by the SLCP, particularly land types that directly involved in the SLCP, such as steeply slope farmlands, degraded grasslands, etc. 展开更多
关键词 SLCP MODIS ND VI Loess hilly and gully area Land use
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Balance of Water Supply-demand in Paddy Fields in Hilly Regions in Sichuan Province
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作者 张鸿 姜心禄 +1 位作者 樊红柱 郑家国 《Agricultural Science & Technology》 CAS 2012年第7期1489-1492,共4页
[Objective] The aim was to study the effects of water supply and consumption on water saving and drought resistance. [Method] Controlling field experiment was conducted to explore water balance between supply and dema... [Objective] The aim was to study the effects of water supply and consumption on water saving and drought resistance. [Method] Controlling field experiment was conducted to explore water balance between supply and demand in paddy fields in hilly regions in Sichuan Province. [Result] Rainfall in hilly areas was 3 611.10 m3/hm2; water for irrigation was 6 299.25 m3/hm2; evapotranspiration of rice was 6 424.95 m3/hm2; deep leakage was 2 459.55 m3/hm2; overflowing amount was 1 026.00 m3/hm2. In addition, water consumption totaled 8 884.50 m3/hm2 during rice production; water use was 0.99 kg/m3 and use efficiency of irrigated water was 1.40 kg/m3. [Conclusion] Water supply and consumption should be further organized to save water and fight against drought in hilly areas in Sichuan Province. 展开更多
关键词 RICE Water balance between supply and demand Sichuan Province hilly areas
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Design and experiment analysis of the small maize harvester with attitude adjustment in the hilly and mountainous areas of China
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作者 Meizhou Chen Guangfei Xu +3 位作者 Yuanzhen Wei Yinping Zhang Peisong Diao Huanxiao Pang 《International Journal of Agricultural and Biological Engineering》 SCIE 2024年第1期118-127,共10页
To solve the problem of small planting plots and large sloping land for mechanized maize harvesting in China hilly and mountainous areas,a small maize harvester with attitude adjustment was designed to realize maize s... To solve the problem of small planting plots and large sloping land for mechanized maize harvesting in China hilly and mountainous areas,a small maize harvester with attitude adjustment was designed to realize maize snapping,peeling,straw crushing and attitude adjusting at on time in this study.The basic structure and working principle of the small maize harvester were described,and the key components were designed as follows.The maize snapping device adopted the combination form of maize snapping plates and straw pulling rollers,and the gap of the straw pulling rollers can be adjusted to adapt to different maize varieties.Two pairs of peeling rollers formed a groove arrangement to improve peeling rate and reduced ear grain loss.The pressure feeding device mainly comprised drive chain and three grade pressure feeding rollers to increase the friction between ears and the peeling rollers,and help ears slide.The attitude adjustment advice was designed according to the high point stationary pursuit leveling method.When the attitude angle of the rack approached 0,the small maize harvester reached the level state.The actual range of attitude adjustment was obtained and the accuracy of static attitude adjustment was verified through attitude adjustment test.The influencing factors of ear loss rate and bract peeling rate were determined by orthogonal test,including the rotational speed of straw pulling rollers,peeling rollers and pressure feeding rollers.The mathematical regression model between the experimental factors and indicators was established by using Design Expert,and through the analysis variance to verify the significance of the evaluation indicators,the best combination of operation parameters was determined that the rotational speed of straw pulling rollers,peeling rollers and pressure feeding rollers were 1440 r/min,1535 r/min and 406 r/min.Under the optimal combination of the operation parameters,the ear loss rate and bract peeling rate were 1.33%and 93.98%.The design indicators of the small maize harvester can meet the relevant national standards,and can satisfy the need of maize mechanized harvesting in China hilly and mountainous areas. 展开更多
关键词 MAIZE HARVESTER hilly and mountains areas attitude adjustment anti rollover structure
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Spatio-temporal Pattern of Cropland Abandonment in Hilly and Mountainous Areas:A Case Study of Jiangxi,China
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作者 WEN Jiaming XIE Hualin 《Journal of Resources and Ecology》 CSCD 2024年第5期1311-1323,共13页
Cropland abandonment is common and widely distributed in hilly and mountainous areas.Clarifying the current situation and development of cropland abandonment can provide reference for the rational and classified manag... Cropland abandonment is common and widely distributed in hilly and mountainous areas.Clarifying the current situation and development of cropland abandonment can provide reference for the rational and classified management of cropland abandonment in hilly and mountainous areas.Taking Jiangxi Province as the study area,and using the Google Earth Engine and Landsat data,the scale and years of abandoned cropland from 2002 to 2020 were calculated by using the random forest classifier and rules for identifying cropland abandonment.The spatio-temporal pattern of cropland abandonment at the county level was analyzed.The results indicated that the overall accuracy of land use classification was over 90%.The cropland abandonment rate ranged from 3%to 5.5%from 2002 to 2020,while the cropland abandonment rate was highest in 2013 and showed a downward trend after 2017.Among the years,the area of first-time abandoned cropland was the largest in 2005.The distribution of the cropland abandonment rate was low in the middle and north,but high in the surrounding area and the south.A notable positive spatial correlation was observed in the cropland abandonment rate,with a gradual intensification of spatial clustering.The LISA cluster map revealed a significant north-south disparity,exhibiting an incremental trend over time in the characteristics of the“High-High”cluster in the Southeastern Mountainous Area and the“Low-Low”cluster in the Poyang Lake Hilly Plain in Jiangxi.The results of this study can provide data for extracting spatial information and analyzing the driving factors of cropland abandonment in hilly and mountainous areas,and they can also provide a basis for the development of policies for the utilization and classification management of abandoned cropland. 展开更多
关键词 cropland abandonment Google Earth Engine hilly and mountainous areas spatio-temporal pattern Jiangxi Province
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Two New Species of Fire-Bellied Newts (Caudata, Salamandridae, Cynops) from Southeastern China
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作者 Zhitong LYU Shuo QI +2 位作者 Siyu ZHANG Keyuan DAI Yingyong WANG 《Asian Herpetological Research》 SCIE CSCD 2023年第1期41-53,I0003,共14页
The fire-bellied newt genus Cynops contains ten known species distributed in China and Japan in East Asia.In this work,two new Cynops species are described,namely Cynops jiaoren sp.nov.distributed in northern Guangdon... The fire-bellied newt genus Cynops contains ten known species distributed in China and Japan in East Asia.In this work,two new Cynops species are described,namely Cynops jiaoren sp.nov.distributed in northern Guangdong and Cynops maguae sp.nov.distributed in eastern Jiangxi.The two new species can be distinctly distinguished from their congeners by the independent phylogenetic placements and a combination of morphological characteristics.The discovery of these two new species in the Southeast Chinese Hilly Area,where half of congeners occur,increases the known diversity of Cynops,and indicates unresolved relationships among the species in southeastern China.Further discussions on the taxonomic status of Cynops cyanurus are also provided. 展开更多
关键词 Cynops jiaoren sp.nov. Cynops maguae sp.nov. Cynops yunnanensis comb.nov. Southeast Chinese hilly area taxonomy
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