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Effects of Fertilization on Moisture Content of Soils in the Loess Hilly-gully Region 被引量:1
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作者 徐宣斌 高照良 《Agricultural Science & Technology》 CAS 2015年第2期278-280,共3页
[Objective] The aim of this study was to study the influence of plants on the soil moisture content under different fertilization.[Method] Using sainfoin,sweet clover,Astragalus adsurgens,alfalfa,ryegrass,little flowe... [Objective] The aim of this study was to study the influence of plants on the soil moisture content under different fertilization.[Method] Using sainfoin,sweet clover,Astragalus adsurgens,alfalfa,ryegrass,little flower,white clover as experimental material,this study explored the effects of soil moisture on the improvement of soil quality.[Result] Results showed that the soil moisture content of different plants follows as:sainfoin 〉sweet clover 〉Astragalus adsurgens 〉alfalfa perennial ryegrass 〉small crown 〉white clover,and the average moisture content reached 24.13% which was 2.45% higher than that of control group.At planting white clover,sweet clover,under the condition of 7 kinds of crops,in the treatments without fertilizer and with organic fertilizer,soil moisture content of soil in 0-20 cm grew significantly.[Conclusion] The application of organic fertilizer and growing of plants would improve soil moisture in abandoned fields,enhance the ability of soil water supply,and improve soil fertility. 展开更多
关键词 Plant FERTILIZER Moisture content of soil Loess hilly-gully region
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De-farming and Ecological Restoration in the Loess Hilly-gully Region in Northern China 被引量:4
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作者 XU Yong TANG Qing MA Dingguo GUO Tengyun 《Journal of Mountain Science》 SCIE CSCD 2006年第2期168-177,共10页
De-farming has been a powerful measure taken by the central and local governments of China for ecological restoration in the loess hilly-gully region since 2000. In years past, aid-based de-farming pattern was far and... De-farming has been a powerful measure taken by the central and local governments of China for ecological restoration in the loess hilly-gully region since 2000. In years past, aid-based de-farming pattern was far and wide popularized in the region and terrace-based de-farming pattern demonstrated in a few small watersheds was also rather effective for ecological restoration. After summing up the features of three patterns (aid-based de-farming slope farmland more than 25°(AD25), aid-based de-farming slope farmland more than 15° (AD15) and terrace-based de-farming (TD)), this paper analyzed the regional difference of these patterns in de-farming area, ecological restoration, investment demand and so on. The results show that there are two crucial areas in the loess hilly-gully region for ecological restoration at the moment, the policies adaptation to the different areas should be constituted as soon as possible and the limited fund should be devoted to the two crucial areas. 展开更多
关键词 De-farming ecological restoration loess hilly-gully region China
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A comparison between different ecological de-farming modes in the loess hilly-gully region in China 被引量:3
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作者 XUYong GUOTengyun YANGGuoan 《Journal of Geographical Sciences》 SCIE CSCD 2005年第1期53-60,共8页
The eco-environmental restoration has been a chief task of the western development strategies carried out by the central and local governments of China since the late 1990s, and the ecological de-farming has been rega... The eco-environmental restoration has been a chief task of the western development strategies carried out by the central and local governments of China since the late 1990s, and the ecological de-farming has been regarded as a powerful measure for the ecological restoration in the Loess Plateau and the upper reaches of the Yangtze River. "Relieving and de-farming" (RD) and "rebuilding terrace and de-farming" (RTD) are two more mature ones among various de-farming modes. Taking the loess hilly-gully region as a case, this paper summarized the basic characteristics of RD and RTD modes, calculated the sizes of de-farming slope farmland, rebuilt terraces, enlarged garden plots and restored vegetation, and compared the differences of two modes in terms of de-farming area, ecological reestablishment index, investment demand amount and benefits. The results showed that RTD mode has many advantages, including suitable investment, sufficient grain supply and great benefits, and will be the best ecological reestablishment mode in the loess hilly-gully region, and RD mode which is being carried out in this region should be replaced by RTD mode as soon as possible. 展开更多
关键词 ecological de-farming mode COMPARISON the loess hilly-gully region
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Research on the Development Model of Ecological Agriculture in Loess Hilly-Gully Region of Northern Shannxi, China 被引量:3
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作者 WangJijun LiuGuobin +2 位作者 XieYongsheng QuanSongar ZhangGanglong 《Ecological Economy》 2005年第2期93-99,共7页
On the Loess Plateau of China, facing the vulnerable environment, local people have to try their best to guarantee the security of food, and at the same time, to control the most serious soil erosion in the world. The... On the Loess Plateau of China, facing the vulnerable environment, local people have to try their best to guarantee the security of food, and at the same time, to control the most serious soil erosion in the world. The paper introduces two typical models of ecological agriculture: ecological agriculture with commodity and agri- culture with soil and water conservation. According to the local natural condition, the model of eco-agriculture with commodity could be characterized by the structure of “agriculture-byproduct”, “agriculture-fruit” or “agri- culture-forestry-husbandry”. The development of agriculture with soil and water conservation has decreased the soil erosion rate from 12,184 ton/km2 in 1980 to 458.4 ton/km2 in 1999, while the farmers’ income has increasingly risen. Analyses on the two models’ benefits both in terms of ecological and agricultural economy show that there is a great possibility to construct or restore good eco-environment with comprehensive control in the hilly-gully area of north Shannxi. Further more, the paper points out the potential problems of foodstuff production and stockbreeding development in forming ecological agriculture and eco-environmental restoration. 展开更多
关键词 loess hilly-gully region ecological agriculture ecological economy PERSPECTIVE China.
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Land-use changes in the small watershed of the Loess Plateau,hilly-gully region, China 被引量:2
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作者 Yini Han Jianzhi Niu Feizhou Wu 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第1期91-99,共9页
As more and more farmland is converted to forestry, the need for effective decision support regarding the use of land in the fragile ecological environment of the Loess Plateau hilly-gully area. The Luoyugou watershed... As more and more farmland is converted to forestry, the need for effective decision support regarding the use of land in the fragile ecological environment of the Loess Plateau hilly-gully area. The Luoyugou watershed was chosen as the study area to calculate the single dynamic degree, integrated dynamic degree, and change indexes of land use, as well as the land-use type transition matrix. This was done by interpreting the TM and SPOT images of the Luoyugou watershed in 1986, 1995, and2004 and making statistical analysis. The results of ou statistical analysis show that the conversion of slope farm land to terrace and forest land plays a dominant role in land-use changes in the Luoyugou watershed from 1986 to2004. The land-use changes are mainly driven by popula tion growth, socio-economic development, consume spending, and investment in forest ecology. 展开更多
关键词 Loess Plateau hilly-gully region Luoyugou watershed Land use and cover changes Driving force
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Compounding soils to improve cropland quality:A study based on field experiments and model simulations in the loess hilly-gully region,China
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作者 HUANG Yun-xin LIU Zheng-jia +2 位作者 LIU Yan-sui LI Yu-rui LIU Xue-qi 《Journal of Mountain Science》 SCIE CSCD 2022年第10期2776-2790,共15页
Increasing the quantity and improving the quality of cropland can alleviate the human-land contradiction and promote the sustainable development of agriculture especially in mountainous areas.With the support of the c... Increasing the quantity and improving the quality of cropland can alleviate the human-land contradiction and promote the sustainable development of agriculture especially in mountainous areas.With the support of the central government’s policies,Yan’an,Northern Shaanxi,China implemented a major land consolidation engineering project in the loess hilly-gully region from 2013 to 2018,achieving 33,333.3 ha of new cropland.However,the poor quality of some newly-constructed cropland at the initial stage hindered its efficient utilization.In order to overcome this problem,red clay and Malan loess were compounded in different volume ratios to explore the method to improve the cropland quality.The Root Zone Water Quality Model was used to simulate the effects of different soil treatments on soil water,nitrogen and maize growth.Experimental data were collected from 2018 to 2019 to calibrate and validate the model.The root mean square error(RMSE)of soil water content,nitrate nitrogen concentration,above-ground biomass,leaf area index were in the range of 11.72-14.06 mm,4.06-11.73 mg kg^(-1),835.21-1151.28 kg ha^(-1)and 0.24-0.47,respectively,while the agreement index(d)between measured and simulated values ranged from 0.70 to 0.96.It was showed that,compared with land constructed with Malan loess only(T1),the soil structure and hydraulic characteristics of land with a volume ratio of red clay and Malan loess of 2:1(T3)was better.Simulation indicated that,compared with T1,the soil water content and available water content of T3 increased by 14.4%and 19.0%,respectively,while N leaching decreased by 16.9%.The aboveground biomass and maize yield of T3 were 7.9%and 6.7%higher than that of T1,respectively.Furthermore,the water productivity and nitrogen use efficiency of T3 increased by 21.0%and 16.6%compared with that of T1.These results indicated that compounding red clay and Malan loess in an appropriate ratio was an effective method to improve soil quality.This study provides a technical idea and specific technical parameters for the construction or improvement of cropland in loess hilly-gully region,which may also provide reference for similar projects in other places. 展开更多
关键词 Soil reconstruction Soil quality Land consolidation engineering High-quality cropland Loess hilly-gully region Root Water Quality Model
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Optimizing field management to promote the ecologicalization of agriculture in loess hilly-gully region,China 被引量:1
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作者 HUANG Yunxin LI Yurui LIU Yansui 《Journal of Geographical Sciences》 SCIE CSCD 2023年第5期1055-1074,共20页
Scientific field management is an important path to realize ecological production and sustainable development of agriculture.As the main content of field management,nitrogen(N)management is the key to balance the econ... Scientific field management is an important path to realize ecological production and sustainable development of agriculture.As the main content of field management,nitrogen(N)management is the key to balance the economic and ecological benefits of agricultural production.In the loess hilly-gully region,for the fragile ecological and social system,ecologicalization of agricultural production is an important direction to promote sustainable agricultural development.However,irrational fertilization has been one of the main constraint factors,hindering the ecologicalization of local agriculture.In order to solve the problem and prove the practical significance of field management to ecologicalization of agriculture,this study aimed at evaluating the effects of different N fertilization rates and timing using Root Zone Water Quality Model(RZWQM)and then optimizing the N management.Experiments were conducted from 2018 to 2019 in Yangjuangou watershed,loess hilly-gully region,to calibrate and validate the model.The root mean square error(RMSE)of soil water content,nitrate N concentration,above-ground biomass,leaf area index ranged from 10.5-13.5 mm,2.96-3.80 mg·kg^(−1),730.3-1273.9 kg·ha^(−1)and 0.26-0.38,respectively,with the agreement index(d)between observed and simulated values ranging between 0.88 to 0.98.Simulation results showed that N leaching in semi-arid areas was also quite high due to concentrated rainfall and loose soil,which had previously been neglected.When the fertilization rate decreased by 35%(applying the chemical fertilizer at rate of 245.7 kg N ha^(−1))of typical fertilization(applying the chemical fertilizer at rate of 378.0 kg N ha^(−1)),the leaching and residual N decreased by 72.2%-75.4%and 35.6%-50.9%,respectively,while NUE increased by 41.5%-45.2%with no reduction in maize yield.Additionally,compared with applying additional N at seedling stage in one batch,applying at seedling and jointing stages in two batches further decreased N leaching and improved NUE.Thus,a 35%reduction of typical fertilization rate combined with applying additional N at seedling and jointing stages is recommended.From the perspective of N management,this study demonstrated optimizing field management can play a positive role in the ecologicalization of agriculture,and more field management measures should be explored. 展开更多
关键词 field management nitrogen fertilization ecologicalization of agriculture gully agriculture loess hilly-gully region
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Construction and Application of a Regional Kilometer-Scale Carbon Source and Sink Assimilation Inversion System(CCMVS-R) 被引量:1
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作者 Lifeng Guo Xiaoye Zhang +8 位作者 Junting Zhong Deying Wang Changhong Miao Licheng Zhao Zijiang Zhou Jie Liao Bo Hu Lingyun Zhu Yan Chen 《Engineering》 SCIE EI CAS CSCD 2024年第2期263-275,共13页
CO_(2)is one of the most important greenhouse gases(GHGs)in the earth’s atmosphere.Since the industrial era,anthropogenic activities have emitted excessive quantities of GHGs into the atmosphere,resulting in climate ... CO_(2)is one of the most important greenhouse gases(GHGs)in the earth’s atmosphere.Since the industrial era,anthropogenic activities have emitted excessive quantities of GHGs into the atmosphere,resulting in climate warming since the 1950s and leading to an increased frequency of extreme weather and climate events.In 2020,China committed to striving for carbon neutrality by 2060.This commitment and China’s consequent actions will result in significant changes in global and regional anthropogenic carbon emissions and therefore require timely,comprehensive,and objective monitoring and verification support(MVS)systems.The MVS approach relies on the top-down assimilation and inversion of atmospheric CO_(2)concentrations,as recommended by the Intergovernmental Panel on Climate Change(IPCC)Inventory Guidelines in 2019.However,the regional high-resolution assimilation and inversion method is still in its initial stage of development.Here,we have constructed an inverse system for carbon sources and sinks at the kilometer level by coupling proper orthogonal decomposition(POD)with four-dimensional variational(4DVar)data assimilation based on the weather research and forecasting-greenhouse gas(WRF-GHG)model.Our China Carbon Monito ring and Verification Support at the Regional level(CCMVS-R)system can continuously assimilate information on atmospheric CO_(2)and other related information and realize the inversion of regional and local anthropogenic carbon emissions and natural terrestrial ecosystem carbon exchange.Atmospheric CO_(2)data were collected from six ground-based monito ring sites in Shanxi Province,China to verify the inversion effect of regio nal anthropogenic carbon emissions by setting ideal and real experiments using a two-layer nesting method(at 27 and 9 km).The uncertainty of the simulated atmospheric CO_(2)decreased significantly,with a root-mean-square error of CO_(2)concentration values between the ideal value and the simulated after assimilation was close to 0.The total anthropogenic carbon emissions in Shanxi Province in 2019 from the assimilated inversions were approximately 28.6%(17%-38%)higher than the mean of five emission inventories using the bottomup method,showing that the top-down CCMVS-R system can obtain more comprehensive information on anthropogenic carbon emissions. 展开更多
关键词 CCMVS-R regional carbon assimilation system Anthropogenic carbon emissions CO_(2) POD 4DVar
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Does digitalization mitigate regional inequalities?Evidence from China
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作者 Haimeng Liu Xinyang Wang +1 位作者 Zheye Wang Yu Cheng 《Geography and Sustainability》 CSCD 2024年第1期52-63,共12页
Regional inequality significantly influences sustainable development and human well-being.In China,there exists pronounced regional disparities in economic and digital advancements;however,scant research delves into t... Regional inequality significantly influences sustainable development and human well-being.In China,there exists pronounced regional disparities in economic and digital advancements;however,scant research delves into the interplay between them.By analyzing the economic development and digitalization gaps at regional and city levels in China,extending the original Cobb-Douglas production function,this study aims to evaluate the impact of digitalization on China's regional inequality using seemingly unrelated regression.The results indicate a greater emphasis on digital inequality compared to economic disparity,with variable coefficients of 0.59 for GDP per capita and 0.92 for the digitalization index over the past four years.However,GDP per capita demonstrates higher spatial concentration than digitalization.Notably,both disparities have shown a gradual reduction in recent years.The southeastern region of the Hu Huanyong Line exhibits superior levels and rates of economic and digital advancement in contrast to the northwestern region.While digitalization propels economic growth,it yields a nuanced impact on achieving balanced regional development,encompassing both positive and negative facets.Our study highlights that the marginal utility of advancing digitalization is more pronounced in less developed regions,but only if the government invests in the digital infrastructure and education in these areas.This study's methodology can be utilized for subsequent research,and our findings hold the potential to the government's regional investment and policy-making. 展开更多
关键词 regional inequality regional disparities Digital divide DIGITALIZATION Sustainable development Economic growth Seemingly unrelated regression
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Assessment of plant diversity of endemic species of the Saharo-Arabian region in Egypt
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作者 Asmaa S ABO HATAB Yassin M AL-SODANY +2 位作者 Kamal H SHALTOUT Soliman A HAROUN Mohamed M EL-KHALAFY 《Journal of Arid Land》 SCIE CSCD 2024年第7期1000-1021,I0002-I0044,共65页
Savanna, semi-deserts, and hot deserts characterize the Saharo-Arabian region, which includes Morocco, Mauretania, Algeria, Tunisia, Libya, Egypt, Palestine, Kuwait, Saudi Arabia, Qatar, Bahrain, the United Arab Emira... Savanna, semi-deserts, and hot deserts characterize the Saharo-Arabian region, which includes Morocco, Mauretania, Algeria, Tunisia, Libya, Egypt, Palestine, Kuwait, Saudi Arabia, Qatar, Bahrain, the United Arab Emirates, Oman, Yemen, southern Jordan, Syria, Iraq, Iran, Afghanistan, Pakistan, and northern India. Its neighboring regions, the Sudano-Zambezian region belonging to the Paleotropical Kingdom and the Mediterranean and Irano-Turanian regions included in the Holarctic Kingdom, share a large portion of their flora with the Saharo-Arabian region. Despite the widespread acknowledgment of the region's global importance for plant diversity, an up to date list of the Saharo-Arabian endemics is still unavailable. The available data are frequently insufficient or out of date at both the whole global and the national scales. Therefore, the present study aims at screening and verifying the Saharo-Arabian endemic plants and determining the phytogeographical distribution of these taxa in the Egyptian flora. Hence, a preliminary list of 429 Saharo-Arabian endemic plants in Egypt was compiled from the available literature. Indeed, by excluding the species that were recorded in any countries or regions outside the Saharo-Arabian region based on different literature, database reviews, and websites, the present study has reduced this number to 126 taxa belonging to 87 genera and 37 families. Regarding the national geographic distribution, South Sinai is the richest region with 83 endemic species compared with other eight phytogeographic regions in Egypt, followed by the Isthmic Desert(the middle of Sinai Peninsula, 53 taxa). Sahara regional subzone(SS1) distributes all the 126 endemic species, Arabian regional subzone(SS2) owns 79 taxa, and Nubo-Sindian subzone(SS3) distributes only 14 endemics. Seven groups were recognized at the fourth level of classification as a result of the application of the two-way indicator species analysis(TWINSPAN) to the Saharo-Arabian endemic species in Egypt, i.e., Ⅰ Asphodelus refractus group, Ⅱ Agathophora alopecuroides var. papillosa group, Ⅲ Anvillea garcinii group, Ⅳ Reseda muricata group, V Agathophora alopecuroides var. alopecuroides group, Ⅵ Scrophularia deserti group, and Ⅶ Astragalus schimperi group. It's crucial to clearly define the Saharo-Arabian endemics and illustrate an updated verified database of these taxa for a given territory for providing future management plans that support the conservation and sustainable use of these valuable species under current thought-provoking devastating impacts of rapid anthropogenic and climate change in this region. 展开更多
关键词 ENDEMISM phytogeographical regions Saharo-Arabian floristic region Egyptian flora plant diversity two-way indicator species analysis(TWINSPAN)
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Investigation of Groundwater Quality with Borehole Depth in the Basin Granitoids of the Ashanti Region of Ghana
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作者 Bernard Ofosu Augustine Kofi Asante +2 位作者 Festus Anane Mensah Umar-Farouk Usman Naa Korkoi Ayeh 《Journal of Water Resource and Protection》 CAS 2024年第5期381-394,共14页
The dependence of groundwater quality on borehole depth is usually debatable in groundwater studies, especially in complex geological formations where aquifer characteristics vary spatially with depth. This study ther... The dependence of groundwater quality on borehole depth is usually debatable in groundwater studies, especially in complex geological formations where aquifer characteristics vary spatially with depth. This study therefore seeks to investigate the relationship between borehole depth and groundwater quality across the granitoid aquifers within the Birimian Supergroup in the Ashanti Region. Physicochemical analysis records of groundwater quality data were collected from 23 boreholes of public and private institutions in the Ashanti Region of Ghana, and the parametric values of iron, fluoride, total hardness, pH, nitrate, and nitrite were used to study the groundwater quality-depth relationship. The results showed that the depth-to-groundwater quality indicated a marginal increase in water quality in the range of 30 to 50 m, which is mathematically represented by the low-value correlation coefficient (r<sup>2</sup> = 0.026). A relatively significant increase occurs in the depth range of 50 to 80 m, which is given by a correlation coefficient of r<sup>2</sup> = 0.298. The mean percent parameter compatibility was 74%, 82%, 89%, and 97% at 50, 60, 70, and 80 m depths, respectively. The variations in groundwater quality per depth ratio ranged from 1.48, 1.37, 1.27, and 1.21 for 50, 60, 70, and 80 m depth, respectively. The recommended minimum borehole depth for excellent groundwater quality is suggested with a compatibility per meter depth ratio of 1.37. This results in a range between 50 and 70 m as the most desirable drilling depth for excellent groundwater quality within the granitoids of the Birimian Supergroup of the Ashanti Region in Ghana. 展开更多
关键词 Groundwater Quality Borehole Depth Birimian Supergroup Granitoid Aquifers Ashanti region
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Prevalence of Enteric Pathogens Associated with Infections among Table Egg Consumers in Some Primary Health Establishments in the Center Region of Cameroon
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作者 Mariane Lucie Ngueguim Bernard Viban Tangwa +2 位作者 Victor Ngu Ngwa Albert Ngakou Abdoulmoumini Mamoudou 《Advances in Infectious Diseases》 CAS 2024年第3期606-619,共14页
Method: In Cameroon limited data are available regarding the prevalence of enteric bacteria associated with table egg consuming infections. As such, a situational-based study was performed in patients with complains o... Method: In Cameroon limited data are available regarding the prevalence of enteric bacteria associated with table egg consuming infections. As such, a situational-based study was performed in patients with complains of stomach disorders after egg consumption. Data related to sociodemographic characteristics and other factors were collected using a structured based questionnaire. Stool culture of utmost importance in stomach disorders patients and serum were collected for typhoid serological test. Results: A total of 207 participants took part in the survey, Results indicated nontyphoidal Salmonella infections were highest in the 3 areas of study with Mfoundi (73.44%) having the highest level of infection compared to other bacterial infection. other enteric bacteria associated to this infection were E. coli serotype 157, Aeromonas, Citrobacter freundii, Enterobacter cloaca and typhi salmonella. Meanwhile salmonelosis caused by typhic salmonella had highest prevalence in the Lekie Division (13.11%) as a result of poor hygienic practices associated with the conservation and preparation of eggs, Stool culture was observed to detect more positive cases in the diagnosis of typhoid fever than Widal test, but with no statistically significant (p > 0.05) difference between the stool culture and Widal test in the 3 areas of study. Conclusion: this study revealed that egg consumers are pruned to enteric bacterial and salmonella infections depending on how and where egg is consumed. 展开更多
关键词 Enteric Pathogens Table Eggs Consumption Center region Cameroon
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Dust-Holding Capacity and Bio-Chemical Changes of Plant Species Growing in an Around Opencast Mining Area of Bundelkhand Region of Uttar Pradesh, India
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作者 Priyanka Singh Amit Pal 《American Journal of Plant Sciences》 CAS 2024年第8期677-698,共22页
The present study has been carried out on a total of 50 available plant species to assess their dust-capturing capacity and biochemical performances in and around open cast granite mine areas of Jhansi district and Bu... The present study has been carried out on a total of 50 available plant species to assess their dust-capturing capacity and biochemical performances in and around open cast granite mine areas of Jhansi district and Bundelkhand University campus treated as control site. Plant species existing under a polluted environment for a long time may be considered as potentially resistant species and recommended for green belt design in mining areas, especially to cope with dust pollution. Results showed the pollution level, especially of mining-originated dust particles holding capacity of leaves and effects of different biochemical parameters (Total Chlorophyll, Protein and Carotenoid) of existing plant species both from mining areas as well as from Bundelkhand University campus. Based on their performances, Tectona grandis L., Ficus hispida L., Calotropis procera Aiton., Butea monosperma Lam. and Ficus benghalensis L., etc. are highly tolerant species while Ficus infectoria L., Artocarpus heterophyllus Lam., Ipomoea purpurea L., Allianthus excelsa Roxb. and Bauhinia variegata L. are intermediate tolerant species. T. grandis had shown the highest dust-holding capacity (2.566 ± 0.0004 mg/cm2) whereas Albizia procera (0.018 ± 0.0002 mg/cm2) was found to be the lowest dust-holding capacity. Our findings also showed that the T. grandis and F. hispida have significant dust deposition with minimal effect of dust on their leaf chlorophyll (17.447 ± 0.019 mg/g and 14.703 ± 0.201 mg/g), protein (0.699 ± 0.001 mg/g and 0.604 ± 0.002 mg/g) and carotenoid (0.372 ± 0.003 mg/g and 0.354 ± 0.003 mg/g) content respectively among all selected plant species. Therefore, in the present investigation, plant species with high tolerance to high dust-holding capacity on their leaf surfaces are preferable for green corridors as open cast granite mines and their adjacent areas. 展开更多
关键词 Bundelkhand region Biochemical Changes Dust-Holding Capacity Chlorophyll Content Open Cast Granite Mining
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Enhancing Autonomy Capability in Regional Power Grids:A Strategic Planning Approach withMultiple Autonomous Evaluation Indexes
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作者 Jie Ma Tong Zhao +8 位作者 Yuanzhao Hao Wenwen Qin Haozheng Yu Mingxuan Du Yuanhong Liu Liang Zhang Shixia Mu Cuiping Li Junhui Li 《Energy Engineering》 EI 2024年第9期2449-2477,共29页
After the integration of large-scale DistributedGeneration(DG)into the distribution network,the randomness and volatility of its output result in a reduction of spatiotemporal alignment between power generation and de... After the integration of large-scale DistributedGeneration(DG)into the distribution network,the randomness and volatility of its output result in a reduction of spatiotemporal alignment between power generation and demand in the distribution network,exacerbating the phenomenon of wind and solar power wastage.As a novel power system model,the fundamental concept of Regional Autonomous Power Grids(RAPGs)is to achieve localized management and energy autonomy,thereby facilitating the effective consumption of DGs.Therefore,this paper proposes a distributed resource planning strategy that enhances the autonomy capabilities of regional power grids by considering multiple evaluation indexes for autonomy.First,a regional Energy Storage(ES)configuration strategy is proposed.This strategy can select a suitable reference value for the upper limit of ES configuration based on the regional load andDGoutput to maximize the elimination of source load deviations in the region as the upper limit constraint of ES capacity.Then,a control strategy for regional ES is proposed,the charging and discharging reference line of ES is set,and multiple autonomy and economic indexes are used as objective functions to select different proportions of ES to control the distributed resources of the regional power grid and establish evaluation indexes of the internal regional generation and load power ratio,the proportion of power supply matching hours,new energy consumption rate and tie line power imbalance outside the region to evaluate changes in the regional autonomy capabilities.The final simulation results showthat in the real regional grid example,the planning method in the planning year in the region of the overall power supply matching hour ratio and new energy consumption rate increased by 3.9%and 4.8%on average,and the power imbalance of the tie line decreased by 7.8%on average.The proposed planning approach enables the maximization of regional autonomy while effectively smoothing the fluctuation of power exchange between the regional grid and the higher-level grid.This presents a rational and effective planning solution for the regional grid,facilitating the coordinated development between the region and the distribution network. 展开更多
关键词 regional autonomous power grid distributed generation distributed energy storage regional planning strategy evaluation index
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Uncertainties of ENSO-related Regional Hadley Circulation Anomalies within Eight Reanalysis Datasets
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作者 Yadi LI Xichen LI +3 位作者 Juan FENG Yi ZHOU Wenzhu WANG Yurong HOU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第1期115-140,共26页
El Nino-Southern Oscillation(ENSO),the leading mode of global interannual variability,usually intensifies the Hadley Circulation(HC),and meanwhile constrains its meridional extension,leading to an equatorward movement... El Nino-Southern Oscillation(ENSO),the leading mode of global interannual variability,usually intensifies the Hadley Circulation(HC),and meanwhile constrains its meridional extension,leading to an equatorward movement of the jet system.Previous studies have investigated the response of HC to ENSO events using different reanalysis datasets and evaluated their capability in capturing the main features of ENSO-associated HC anomalies.However,these studies mainly focused on the global HC,represented by a zonal-mean mass stream function(MSF).Comparatively fewer studies have evaluated HC responses from a regional perspective,partly due to the prerequisite of the Stokes MSF,which prevents us from integrating a regional HC.In this study,we adopt a recently developed technique to construct the three-dimensional structure of HC and evaluate the capability of eight state-of-the-art reanalyses in reproducing the regional HC response to ENSO events.Results show that all eight reanalyses reproduce the spatial structure of HC responses well,with an intensified HC around the central-eastern Pacific but weakened circulations around the Indo-Pacific warm pool and tropical Atlantic.The spatial correlation coefficient of the three-dimensional HC anomalies among the different datasets is always larger than 0.93.However,these datasets may not capture the amplitudes of the HC responses well.This uncertainty is especially large for ENSO-associated equatorially asymmetric HC anomalies,with the maximum amplitude in Climate Forecast System Reanalysis(CFSR)being about 2.7 times the minimum value in the Twentieth Century Reanalysis(20CR).One should be careful when using reanalysis data to evaluate the intensity of ENSO-associated HC anomalies. 展开更多
关键词 regional Hadley circulation ENSO atmosphere-ocean interaction reanalysis data
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Factors of Adherence to Concurrent Tuberculosis Treatment and Antiretroviral Therapy among HIV-TB Co-Infected Individuals in the East Region, Cameroon in the COVID-19 Era: A Retrospective Cohort Study
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作者 François Anicet Onana Akoa Ulrich Dama +5 位作者 Jean Ndibi Abanda Alphonse Tedonge Asobochia Melkior Fobasso Dzeuta Pearl Nsom Mbu Yokyu Zachary Pangwoh Pierre Yassa Yoniene 《Health》 2024年第2期131-147,共17页
Context/Objectives: Tuberculosis (TB) and HIV co-infection is a serious health problem in Cameroon. The problems associated with poor adherence to treatment are on the increase worldwide. This problem can be observed ... Context/Objectives: Tuberculosis (TB) and HIV co-infection is a serious health problem in Cameroon. The problems associated with poor adherence to treatment are on the increase worldwide. This problem can be observed in all situations where patients are required to administer their own medication, whatever the type of illness. The general objective of this study was to assess the factors affecting adherence to treatment among HIV-TB co-infected patients in health facilities in the East Region in the COVID context. Method: A retrospective cohort study before and during COVID-19 was conducted in HIV care units in 13 health districts in the East Region of Cameroon. Data were collected using a questionnaire recorded in the Kobo Collect android application, analyzed using SPSS version 25 software and plotted using Excel. Results: The pre-COVID-19 cohort compared to the during-COVID-19 cohort had a 1.90 risk of not adhering to treatment (OR: 1.90, CI {1.90 - 3.37}) and the difference was statistically significant at the 5% level (p-value = 0.029). Frequency of adherence was 65.4% (140/214). Adherence before COVID-19 was 56.9% whereas during COVID-19, it was 74.3%. Conclusion: The implementation of targeted interventions in the COVID-19 context, using evidence-based data and integrating the individual needs of HIV-TB co-infected patients, improved adherence to concurrent anti-tuberculosis treatment and antiretroviral therapy during the COVID-19 Era. 展开更多
关键词 Factors of Adherence Tuberculosis Treatment Antiretroviral Therapy HIV-TB Co-Infection East region Cameroon
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Regional economic assessment of a novel place-based model for sustainable food systems
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作者 Susanna Kujala Kari Koppelmäki 《Geography and Sustainability》 CSCD 2024年第2期220-229,共10页
Several actions from both the environmental and human viewpoints have already been made to meet the sustainability goals targeted at food systems.Still,new place-based ideas to improve sustainability are needed.Agroec... Several actions from both the environmental and human viewpoints have already been made to meet the sustainability goals targeted at food systems.Still,new place-based ideas to improve sustainability are needed.Agroecological symbiosis(AES),a novel food system model,is an example of a suggested system-level change to attain sustainability targets;it is a symbiosis of food production and processing using renewable energy that uses its own feedstock.AES has already been found advantageous from the ecological and biophysical viewpoints,but a regional economic evaluation of the model is still lacking.Thus,the aim of our paper is to assess the regional economic impact of a possible systemic change in the food system using the network of agroecological symbiosis(NAES)as an example.We applied scenarios representing different ways of moving towards envisioned NAES models in Mäntsälä,Finland,and a computable general equilibrium model to evaluate the regional economic impact.According to our results,both regional economy and employment would increase,and the regional production base would diversify with NAES implementation applied to the region,but the extent of the benefits varies between scenarios.The scenario that includes change in both public and private food demand,production of bioenergy and utilization of by-products would cause the largest impacts.However,realizing NAES requires investments that may influence the actual implementation of such models.Nonetheless,a change towards NAES can promote an economically and spatially just transition to sustainability,as NAES seems to be economically most beneficial for rural areas. 展开更多
关键词 SUSTAINABILITY regional economy Localized food system Renewable energy CIRCULARITY
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Individual alcohol consumption by the population of Russia versus regional living conditions
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作者 Sergey A.Maksimov Svetlana A.Shalnova +4 位作者 Galina A.Muromtseva Yuliya A.Balanova Svetlana E.Evstifeeva Anna V.Kapustina Oksana M.Drapkina 《Global Health Journal》 2024年第1期24-31,共8页
Background:There are substantial regional differences in drinking alcohol in Russia,both at the population and individual levels.However,the causes of these differences have not been studied yet.Objective:The goal of ... Background:There are substantial regional differences in drinking alcohol in Russia,both at the population and individual levels.However,the causes of these differences have not been studied yet.Objective:The goal of our study was to examine the effect of regional living conditions on individual alcohol consumption by the population of Russia.Methods:For the analysis,we used data from a cross-sectional epidemiological study conducted in 2013-2014.The final analytical sample included 18,130 people aged 25-64 years.We conducted the interviews face to face,based on which any drinking in the last year,as well as alcohol abuse,were considered as a response.Alcohol abuse was recorded when the respondent consumed 5.75 or more grams of pure ethanol per day(75th percentile of average daily alcohol consumption among alcohol drinkers).The assessment of the regional living conditions was accomplished via integral indexing,which was previously performed based on publicly available data for 2010-2014.Associations were assessed using generalized scoring equations with unchanging standard errors.The associations were expressed by odds ratios(OR)and 95%confidence intervals(C).Results:Deterioration of social conditions and increase in demographic depression in the region of residence increased the odds of any drinking(OR 1.51,95%CI:1.33 to 1.72,P<0.001 and OR 1.22,95%CI:1.05 to 1.41,P=0.oo9,respectively).The odds of alcohol abuse increased with the deterioration of social living conditions and the growth of the industrial development in the region:OR 1.35,95%CI:1.14 to 1.59,P<0.001 and OR 1.16,95%CI:1.05 to 1.28,P=0.002,respectively.Conclusion:Our analysis allowed assessing the impact of the regional living conditions on individual drinking alcohol in the population of Russia. 展开更多
关键词 ALCOHOL Living environment regional features RUSSIA
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Image Hiding with High Robustness Based on Dynamic Region Attention in the Wavelet Domain
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作者 Zengxiang Li Yongchong Wu +3 位作者 Alanoud Al Mazroa Donghua Jiang Jianhua Wu Xishun Zhu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期847-869,共23页
Hidden capacity,concealment,security,and robustness are essential indicators of hiding algorithms.Currently,hiding algorithms tend to focus on algorithmic capacity,concealment,and security but often overlook the robus... Hidden capacity,concealment,security,and robustness are essential indicators of hiding algorithms.Currently,hiding algorithms tend to focus on algorithmic capacity,concealment,and security but often overlook the robustness of the algorithms.In practical applications,the container can suffer from damage caused by noise,cropping,and other attacks during transmission,resulting in challenging or even impossible complete recovery of the secret image.An image hiding algorithm based on dynamic region attention in the multi-scale wavelet domain is proposed to address this issue and enhance the robustness of hiding algorithms.In this proposed algorithm,a secret image of size 256×256 is first decomposed using an eight-level Haar wavelet transform.The wavelet transform generates one coefficient in the approximation component and twenty-four detail bands,which are then embedded into the carrier image via a hiding network.During the recovery process,the container image is divided into four non-overlapping parts,each employed to reconstruct a low-resolution secret image.These lowresolution secret images are combined using densemodules to obtain a high-quality secret image.The experimental results showed that even under destructive attacks on the container image,the proposed algorithm is successful in recovering a high-quality secret image,indicating that the algorithm exhibits a high degree of robustness against various attacks.The proposed algorithm effectively addresses the robustness issue by incorporating both spatial and channel attention mechanisms in the multi-scale wavelet domain,making it suitable for practical applications.In conclusion,the image hiding algorithm introduced in this study offers significant improvements in robustness compared to existing algorithms.Its ability to recover high-quality secret images even in the presence of destructive attacksmakes it an attractive option for various applications.Further research and experimentation can explore the algorithm’s performance under different scenarios and expand its potential applications. 展开更多
关键词 Image hiding ROBUSTNESS wavelet transform dynamic region attention
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MAVEN observation of magnetosonic waves in the Martian magnetotail region
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作者 ShangChun Teng JiCheng Sun +3 位作者 JiaWei Gao Y.Harada Markus Fraenz DeSheng Han 《Earth and Planetary Physics》 EI CAS CSCD 2024年第2期317-325,共9页
Magnetosonic waves are an important medium for energy transfer in collisionless space plasma.Magnetosonic waves have been widely investigated in the upstream of the bow shock at Mars.These waves are believed to origin... Magnetosonic waves are an important medium for energy transfer in collisionless space plasma.Magnetosonic waves have been widely investigated in the upstream of the bow shock at Mars.These waves are believed to originate from pickup ions or reflected particles.By utilizing MAVEN spacecraft data,we have observed the occurrence of quasi-perpendicularly propagating magnetosonic emissions near the proton gyrofrequency in the Martian magnetotail region.These plasma waves are associated with a significant enhancement of proton and oxygen flux.The excited magnetosonic waves could possibly heat the protons through resonance and facilitate the ionospheric plasma escape.Our results could be helpful to better understand the Mars’magnetospheric dynamics and offer insights into possible energy redistribution between waves and plasma in the Martian nightside magnetosphere. 展开更多
关键词 Martian magnetotail region magnetosonic waves proton escape
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