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Effects of Microbial Fertilizers on Soil Improvement and Wheat Growth Characteristics in Saline-alkali Land
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作者 Gen SONG Ziru LI +12 位作者 Baohai ZHANG Zhenhua JIA Jirong CUI Dingxin GUO Lili HAN Yanhong WU Jianlong FENG Yan GAO Mingying LIU Chunguang SONG Guojia JI Changsong WANG Zhiwei ZHANG 《Agricultural Biotechnology》 2024年第4期76-81,共6页
[Objectives]This study was conducted to further enrich the research on saline-alkali land improvement,and explore the effects of biological bacterial fertilizers containing Bacillus subtilis and Bacillus velezensis HM... [Objectives]This study was conducted to further enrich the research on saline-alkali land improvement,and explore the effects of biological bacterial fertilizers containing Bacillus subtilis and Bacillus velezensis HM-3 in saline-alkali land improvement and crop growth promotion.[Methods]Wheat was planted in saline-alkali land in Huanghua City,Hebei Province,and a mixed application experiment was carried out using biological agents from Hemiao Biotechnology Co.,Ltd.[Results]Compared with the field of control check(CK),water-soluble salts and pH value in the experimental fields decreased,and living bacteria count in the soil increased.Meanwhile,the economic characters of wheat in the experimental fields showed excellent performance,with yields increasing by 39.09%and 27.49%compared with the CK.It could be seen that the application of biological bacterial fertilizers achieved obvious effects of improving saline-alkali soil and increasing wheat yield.[Conclusions]In this study,the effects of biological bacterial fertilizers on saline-alkali land and wheat growth characters were clarified,providing some technical support and theoretical guidance for wheat planting in Huanghua saline-alkali land. 展开更多
关键词 saline-alkali land Soil improvement WHEAT YIELD
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Bohai Granary:Harnessing the Saline-Alkali Lands
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作者 LIU Xiaojing 《Bulletin of the Chinese Academy of Sciences》 2024年第4期244-250,共7页
Agriculture forms the backbone of a nation,and food security is essential for social stability and sustainable economic growth.In China,ensuring adequate food production is not only critical for national well-being bu... Agriculture forms the backbone of a nation,and food security is essential for social stability and sustainable economic growth.In China,ensuring adequate food production is not only critical for national well-being but also a strategic priority for maintaining self-sufficiency.To enhance food security,two key approaches are increasing yields from the existing agricultural lands and improving the productivity of low-and medium-yield farmland.One of China’s major underutilized resources is its extensive saline-alkali lands,which,despite historically low productivity due to poor soil conditions and scarce freshwater resources,hold immense potential for boosting grain output.Recognizing this,the Chinese Academy of Sciences,in collaboration with the Chinese Ministry of Science and Technology(MOST),initiated the“Bohai Granary Scientific and Technological Demonstration Project”(Bohai Granary Project for short)in partnership with three provinces and one municipality-Hebei,Shandong,Liaoning,and Tianjin.This project represents a landmark effort to rehabilitate saline-alkali lands and transform them into highly productive grain-producing regions,thereby contributing significantly to China’s food security strategy.In this article,the author revisits the key milestones,technological breakthroughs,and outlook on the future potential of this project. 展开更多
关键词 food security saline-alkali land Bohai Granary Project soil improvement agricultural innovation
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Initial Exploration on Effect of Saline-alkali Land Rebuilding and Utilization by Fenlong Cultivation 被引量:2
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作者 韦本辉 申章佑 +6 位作者 周佳 甘秀芹 劳承英 周灵芝 刘斌 胡泊 李艳英 《Agricultural Science & Technology》 CAS 2017年第12期2396-2400,共5页
In order to explore the effect of Fenlong cultivation in rebuilding and uti- lization of saline-alkali land, the Fenlong tillage machine and Fenlong technology were invented and put into tests in the saline-alkali lan... In order to explore the effect of Fenlong cultivation in rebuilding and uti- lization of saline-alkali land, the Fenlong tillage machine and Fenlong technology were invented and put into tests in the saline-alkali land from 2015-2016 in Xinjiang Autonomous Region and Shaanxi province, respectively. The results showed that in Xinjiang, the total salt content in the heavy saline-alkali soil decreased by 31.31% after one season of cotton planting using Fenlong, while cotton yield increased by 48.80%, and the soil salinity level was fallen from "severe" to "moderate" level. In Shaanxi, the total salt content in decreased by 42.73% after planting summer corn summer corn the mild saline-alkali land using Fenlong cultivation, while the corn yield increased by 34.83%, and the soil salinity degree was changed from "mild de- salination" to "normal farmland". At last, the paper provided the mechanism and reasons for desalination in soil and yield increase by Fenlong cultivation. 展开更多
关键词 Fenlong cultivation saline-alkali land DESALINATION Yield increase PROSPECT
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Study on the Landscaping Technologies for Coastal Saline-Alkali Land in Tanghai County of Tangshan City
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作者 潘冬梅 袁卫国 +3 位作者 杜金城 郭淑英 郑艳美 何新红 《Journal of Landscape Research》 2010年第2期1-4,共4页
Tanghai County is one of the counties in Tangshan City with the highest saline-alkali degree, with 80% of its land being covered by saline-alkali soils. Through studying landscaping technologies for coastal saline-alk... Tanghai County is one of the counties in Tangshan City with the highest saline-alkali degree, with 80% of its land being covered by saline-alkali soils. Through studying landscaping technologies for coastal saline-alkali land in Tanghai County, 3 dominant modes for landscaping engineering in such land were summarized as shallow underground pipe desalination technology, banding soil replacement technology and hole membrane soil replacement technology, which are different in application scope and also in cost (respectively 260, 210 and 170 yuan). 3 landscaping measures were also proposed, including promotion of suitable plant cultivation technologies, application of saline-alkali tolerant plants and biological improvement of soils. To explore economic and practical planting patterns for saline-alkali land, low-cost landscaping tests were conducted from the perspectives of improving landscaping engineering mode and optimizing landscaping measures, and the results showed that it was practical to apply low-cost landscaping patterns, and comprehensive ecological measures should be adopted to realize the sustained utilization of soil. 展开更多
关键词 Tanghai County Coastal saline-alkali land landscaping engineering mode Low cost Sustained utilization
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Dynamics of Saline-alkali Land and Its Ecological Regionalization in Western Songnen Plain, China 被引量:18
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作者 YANG Jiuchun ZHANG Shuwen +4 位作者 LI Ying BU Kun ZHANG Yubo CHANG Liping ZHANG Yangzhen 《Chinese Geographical Science》 SCIE CSCD 2010年第2期159-166,共8页
As the important reserve land resources for food production,saline-alkali land should play a significant role to ensure the national food security in the context of global food crisis. The western Songnen Plain is one... As the important reserve land resources for food production,saline-alkali land should play a significant role to ensure the national food security in the context of global food crisis. The western Songnen Plain is one of main distribution regions of saline-alkali land in China,with great potential in agricultural development. In this study,the extent,transformation,spatial distribution and temporal change of saline-alkali land in the western Songnen Plain during 1954–2005 were investigated by using remote sensing and GIS spatial analysis methods. Saline-alkali land change was detected from a temporal series of topographic maps in 1954,satellite images of Landsat MSS in 1976,Landsat TM/ETM in 1988,2000 and 2005 through artificial visual interpretation. The results indicated a significant expansion in saline-alkali land area and aggravation in salinization. The area of saline-alkali land had increased from 401.48×103 ha in 1954 to 1 097.45×103 ha in 2005. While the ratio of light,moderate and serious salinized land areas changed from 6.72︰2.92︰1.00 to 1.25︰1.06︰1.00 in the study period. Grassland,cropland,swampland and water body were the major land use and land cover types from which saline-alkali land transformed. And the secondary salinization occured mainly in Da′an City,Tongyu County,Changling County,Daqing City,Dorbod Mongolian Autonomous County and Zhaoyuan County. Finally,seven large ecoregions and 14 corresponding sub-ecoregions were delineated out based on spatio-temopral dynamic characteristics of saline-alkali land and geo-relational environmental attributes. According to the results,measures of amelioration and ways of development of saline-alkali land in the western Songnen Plain were put forward. 展开更多
关键词 saline-alkali land SALINIZATION ecological regionalization food security Songnen Plain
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Saline-alkali land in the Yellow River Delta: amelioration zonation based on GIS 被引量:3
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作者 GUAN Yuan-xiu, LIU Gao-huan, WANG Jin-feng (State Key Laboratory of Resources and Environment Information System, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第3期313-320,共8页
Soil salinization is one of the major land degradation types and has greatly influenced sustainable agricultural development. Zonation of saline-alkali land is the precondition for effective amelioration. The present ... Soil salinization is one of the major land degradation types and has greatly influenced sustainable agricultural development. Zonation of saline-alkali land is the precondition for effective amelioration. The present situation of saline-alkali land is monitored by remote sensing image processing. Causes for land salinization are analyzed, especially the two key factors, ground water depth and its mineralization degree, are analyzed by using long-term observation data. Previously, zonation of saline-alkali soil was made descriptively and artificially. Based on the present situation of saline-alkali land, ground water depth and ground water mineralization degree, the zonation of saline-alkali land for amelioration in the Yellow River Delta was completed quantitatively. Four different types of saline-alkali land amelioration zones are delineated, namely, easy ameliorated zone, relatively difficult ameliorated zone, difficult ameliorated zone and unfavorable ameliorated zone. Countermeasures for ameliorating saline-alkali soils are put forward according to ecological conditions of different saline-alkali land zones. 展开更多
关键词 GIS the Yellow River Delta saline-alkali land ZONATION
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Quantitative Assessment of Impacts of Regional Climate and Human Activities on Saline-alkali Land Changes:A Case Study of Qian'an County,Jilin Province 被引量:3
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作者 LIAN Yi WANG Jie +5 位作者 TU Gang REN Hongling SHEN Baizhu ZHI Keguang LI Shangfeng GAO Zongting 《Chinese Geographical Science》 SCIE CSCD 2010年第1期91-97,共7页
Interdecadal and interannuat variations of saline-alkali land area in Qian'an County, Jilin Province, China were comprehensively analyzed in this paper by means of satellite remote sensing interpretation, field flux ... Interdecadal and interannuat variations of saline-alkali land area in Qian'an County, Jilin Province, China were comprehensively analyzed in this paper by means of satellite remote sensing interpretation, field flux observations and regional climate diagnosis. The results show that on the interannual scale, the impact of climate factors accounts for 71.6% of the total variation of the saline-alkali land area, and that of human activities accounts for 28.4%. Therefore the impact of climate factors is obviously greater than that of human activities. On the interdecadal scale, the impact of climate factors on the increase of the saline-alkali land area accounts for 43.2%, and that of human activities accounts for 56.8%. The impact of human activities on the variation of saline-alkali land area is very clear on the interdecadal scale, and the negative impact of human activities on the environment should not be negligible. Besides, changes in the area of heavy saline-alkali land have some indication for development of saline-alkali land in Qian'an County. 展开更多
关键词 saline-alkali land regional climate change human activities
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The Salt Reduction and Yield Increase Effects of Smashing Ridging Transforming Saline-alkali Land and Its Development Prospects 被引量:3
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作者 Wei Benhui Shen Zhangyou +5 位作者 Zhou Jia Zhou Lingzhi Gan Xiuqin Lao Chengying Li Yanying Hu Po 《Meteorological and Environmental Research》 CAS 2018年第4期112-115,120,共5页
Using smashing ridging tillage machine and smashing ridging technology invented by the authors, transformation test of saline-alkali land by smashing ridging was conducted respectively in Xinjiang and Shaanxi during 2... Using smashing ridging tillage machine and smashing ridging technology invented by the authors, transformation test of saline-alkali land by smashing ridging was conducted respectively in Xinjiang and Shaanxi during 2015 -2016. The results showed, in severe saline-alkali soil of Xin-jiang ,after growing cotton by smashing ridging, total salt in soil decreased by 31.31 %, cotton production increased by 48.80%, and salinity level declined from severe to moderate; in mild saline-alkali soil of Shaanxi, after growing summer corn by smashing ridging, total salt in soil decreased by 42.37%, corn yield increased by 34.83%, salinity degree changed from mild desalination to normal farmland ; in Ningxia, Inner Mongolia 7 Gansu ,Jilin, Henan, Hebei, and so on, smashing ridging tillage practice in different types of saline-alkali land was conducted ; according to the salt reduction and yield increase effects of saline-alkali land after smashing ridging, the development prospect of smashing ridging technique in improvement and application of saline-alkali land was proposed. 展开更多
关键词 Smashing ridging saline-alkali land IMPROVEMENT Salt reduction Yield increase PROSPECT
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A GIS-based Tupu Analysis of Dynamics of Saline-alkali Land in Western Jilin Province 被引量:1
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作者 REN Chunying ZHANG Bai +3 位作者 WANG Zongming SONG Kaishan LIU Dianwei LIU Zhiming 《Chinese Geographical Science》 SCIE CSCD 2007年第4期333-340,共8页
Based on Tupu theory, this paper studied the dynamic changes, conversion modes, expansion intensity and landscape attributes of the saline-alkali lands in Changling County, Zhenlai County and Da'an City of the wes... Based on Tupu theory, this paper studied the dynamic changes, conversion modes, expansion intensity and landscape attributes of the saline-alkali lands in Changling County, Zhenlai County and Da'an City of the western Jilin Province in 1980-2000 with the help of GIS. The results show that the saline-alkali land rather sharply increased in Da'an during 1995-2000; the main conversion processes in the three counties were from grassland to saline-alkali land and from saline-alkali land to grassland; and the typical shapes, spatial expansion speed and mode, and landscape attributes of the saline-alkali land were different in the three counties, which were closely related to local topography, predominant wind orientation, water resources distribution, etc. The corresponding spatial expansion mode was marginality in Changling, random in Zhenlai and more kernels in Da'an, respectively. Landscape attributes also responded to the spatial-temporal dynamic changes of the saline-alkali land and the landscape indices of Da'an fluctuated greatly. The frame of this research may provide fundamental reference for landscape analysis and give some suggestions for regional sustainable development. 展开更多
关键词 Tupu saline-alkali land GIS Jilin Province
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Effects of Soil Improver on Wheat in Saline-Alkali Lands in the Yellow River Delta
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作者 Liang DONG Shenzhong TIAN +6 位作者 Zeqiang SUN Xuejun WANG Zhaohui LIU Ruiqin LI Ye TIAN Deshui TAN Jiafa LUO 《Agricultural Biotechnology》 CAS 2019年第2期133-136,共4页
Field experiment carried out to test the effects of soil improver on wheat yield and soil physical-chemical properties. The results indicated that soil improver could optimize soil aggregates structure, decrease soil ... Field experiment carried out to test the effects of soil improver on wheat yield and soil physical-chemical properties. The results indicated that soil improver could optimize soil aggregates structure, decrease soil bulk density, soil pH and soil salt content, increase soil organic matter and 1 000-grain weight, thereby enhancing wheat yield. With the increase of soil improver application amount, soil physical-chemical properties became better and wheat yield increased. However, there was no significant difference in the treatments with the application amounts of 3%, 4% and 5%. In addition, the treatment of reducing nitrogen showed no superiority in soil physical-chemical properties and wheat yield, indicating that sufficient nitrogen was essential for the growth of wheat. 展开更多
关键词 SOIL improver saline-alkali land WHEAT
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A Meta-Analysis of 30 Years in China and Micro-District Experiments Shows Organic Fertilizer Quantification Combined with Chemical Fertilizer Reduction Enhances Rice Yield on Saline-Alkali Land
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作者 HE Chen RUAN Yunze JIA Zhongjun 《Rice science》 2025年第2期259-272,I0055-I0059,共19页
To improve the yield and quality of rice grown on saline-alkali soil,a meta-analysis combined with micro-district experimental studies was conducted in China to examine the impact of humic acidbased organic fertilizer... To improve the yield and quality of rice grown on saline-alkali soil,a meta-analysis combined with micro-district experimental studies was conducted in China to examine the impact of humic acidbased organic fertilizer and chemical fertilizer on rice yield and quality.This study employed a two-factor fully randomized experimental design,incorporating four levels of humic acid(F0,0.0 g/pot;F1,4.8 g/pot;F2,12.0 g/pot;and F3,19.2 g/pot)and three levels of chemical fertilizer(A1,full conventional dosage;A2,85% of conventional dosage;and A3,70% of conventional dosage).The meta-analysis revealed that the application of organic fertilizer(at a rate of 1500‒3000 kg/hm^(2))combined with chemical fertilizer had a significantly positive effect on the theoretical yield,tiller number,partial factor productivity,and SPAD value of rice.Temperature,organic fertilizer application,and chemical fertilizer levels were identified as critical factors affecting rice yield.The micro-experiments demonstrated that the application of humic acid organic fertilizer with treatment F3 significantly elevated the SPAD value at the full heading and grain filling stages.Increased panicle number and seed-setting rate were the main contributors to the rise in yield,with the F3 treatment yielding the highest overall.The effective leaf area,high-efficiency leaf area,and dry matter accumulation in rice treated with F3 were all higher compared with the F0 treatment.Our findings indicated that the addition of humic acid organic fertilizer can markedly improve the partial factor productivity and agronomic efficiency of rice.In conclusion,the application of F3 organic fertilizer combined with A3 chemical fertilizer(F3A3)significantly increased the yield of saline-alkali rice,which was 6.62% higher than that of the F0A1 treatment,thereby validating the meta-analysis outcomes.We propose that the combined use of humic acid organic fertilizer and chemical fertilizer can promote the growth of rice in saline-alkali soils.Consequently,these management practices provide a means to foster the green and healthy development of rice in saline-alkali regions across China. 展开更多
关键词 humic acid chemical fertilizer rice yield saline-alkali land
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Saline-alkali land reclamation boosts topsoil carbon storage by preferentially accumulating plant-derived carbon 被引量:4
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作者 Lin Chen Guixiang Zhou +7 位作者 Biao Feng a Chao Wang Yu Luo Fang Li Congcong Shen Donghao Ma Congzhi Zhang Jiabao Zhang 《Science Bulletin》 SCIE EI CAS CSCD 2024年第18期2948-2958,共11页
Saline–alkali land is an important cultivated land reserve resource for tackling global climate change and ensuring food security, partly because it can store large amounts of carbon(C). However, it is unclear how sa... Saline–alkali land is an important cultivated land reserve resource for tackling global climate change and ensuring food security, partly because it can store large amounts of carbon(C). However, it is unclear how saline–alkali land reclamation(converting saline–alkali land into cultivated land) affects soil C storage.We collected 189 adjacent pairs of salt-affected and cultivated soil samples(0–30 cm deep) from the Songnen Plain, eastern coastal area, Hetao Plain, and northwestern arid area in China. Various soil properties, the soil inorganic C(SIC), organic C(SOC), particulate organic C(POC), and mineral-associated organic C(MAOC) densities, and plant-and microbial-derived C accumulation were determined.Saline–alkali land reclamation inconsistently affected the SIC density but significantly(P < 0.001)increased the SOC density. The SOC, POC, and MAOC densities were predicted well by the integrative soil amelioration index. Saline–alkali land reclamation significantly increased plant-derived C accumulation and the plant-derived C to microbial-derived C ratios in all saline–alkali areas, and less microbial transformation of plant-derived C(i.e., less lignin degradation or oxidation) occurred in cultivated soils than salt-affected soils. The results indicated that saline–alkali land reclamation leads to plant-derived C becoming the dominant contributor of SOC storage. POC storage and MAOC storage were strongly linked to plant-and microbial-derived C accumulation, respectively, caused by saline–alkali land reclamation.Our findings suggest that saline–alkali land reclamation increases C storage in topsoil by preferentially promoting plant-derived C accumulation. 展开更多
关键词 saline-alkali land Salt-affected soil Particulate organic carbon Mineral-associated organic carbon Plant-derived carbon
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Design and test of a dual-axis layered rotary tillage stubble exterminator in saline-alkali land based on discrete elements
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作者 Zhuang Zhao Dongwei Wang +5 位作者 Shuqi Shang Peng Guo Zenghui Gao Chao Xia Haipeng Yan Jialin Hou 《International Journal of Agricultural and Biological Engineering》 SCIE 2024年第5期163-175,共13页
Considering the problems of poor straw mulching performance,low soil crushing rate and poor straw mulching performance of the traditional rotary tiller on saline-alkali soils,a two-axis layered rotary stubble cutter f... Considering the problems of poor straw mulching performance,low soil crushing rate and poor straw mulching performance of the traditional rotary tiller on saline-alkali soils,a two-axis layered rotary stubble cutter for saline-alkali soils with front-axis positive rotation of the front axle and rear-axis counter-rotation of the rear axle was developed,focusing on the kinetic properties of the straw and soil under positive and counter-rotation.In addition,the most important structural parameters and the arrangement of the front-axis stubble cutting knife and the rear-axis return knife were analyzed and determined.Hertz-Mindlin with bonding was used to create a discrete element model of the agglomerate of implement,straw and soil.The forward speed,horizontal distance and vertical distance were used as test factors,and the straw return rate and soil fragmentation rate were used as test indexes to analyze the straw-soil transport law under different operating parameters from a microscopic point of view,and then Design-Expert was used to conduct the test 1.07 km/h,horizontal distance of 569.55 mm,vertical distance of 176.59 mm.To validate the performance of the two-axis,layered rotary tiller,a field trial was conducted and the results show that the straw return ratio was(91.59±0.41)%,soil fragmentation ratio was(91.90±0.29)%and tillage depth stability was(91.52±0.46)%,which met the requirements for peanut seedbed preparation on saline-alkali land. 展开更多
关键词 saline-alkali land straw return soil fragmentation dual-axis layering discrete element simulation field trial
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Optimizing Model Land Use and Crop Productivity in Agroforestry Farms for Food Security of Small Farmers in Burundi
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作者 Audace Niyonzima Heidi Megerle +5 位作者 Habonimana Bernadette Christina Weber Ndihokubwayo Soter Jannis Bahnmüller Ngendakumana Serge Niragira Sanctus 《Agricultural Sciences》 2025年第1期123-145,共23页
Burundi faces major agricultural constraints, including land fragmentation, soil erosion, limited access to inputs, inadequate infrastructure and demographic pressures that exacerbate food insecurity. In order to addr... Burundi faces major agricultural constraints, including land fragmentation, soil erosion, limited access to inputs, inadequate infrastructure and demographic pressures that exacerbate food insecurity. In order to address the multiple challenges faced by farmers in rural areas, a study on improving agricultural productivity and food security in Burundi through optimized land use and diversified farming practices in agroforestry systems has been carried out. The study area is the communes of Giheta and Rutegama, all located in Burundi’s humid plateau livelihood zone, and involved 164 households grouped in coffee growing cooperatives supervised by the cooperative consortium COCOCA. The study uses a mathematical programming model to determine optimal crop selection based on factors such as production costs, yields and market demand. The findings of the study revealed significant insights into the demographic and socio-economic characteristics of the sampled population. Notably, 98.8% of respondents were engaged in agriculture, confirming the predominantly agricultural nature of Burundi. The results indicated that maize is the most important crop, occupying 33.9% of the average total cultivated area, followed by cassava at 26.5% and bananas at 19.4%. Together, these three crops accounted for a substantial portion of the total cultivated area, highlighting their significance in local agriculture. Beans and potatoes also play a role, occupying 14.4% and smaller areas, respectively. In terms of profitability, the study provides a detailed analysis of profit margins by crop. Bananas emerges as the most profitable crop, with a profit margin of 97.3%, followed closely by cassava at 96.1% and rice at 90.5%. These crops not only offered substantial yields relative to their production costs but also benefited from strong market demand. Other crops, such as beans (71.3%), coffee (70.3%), and vegetables (54.5%), also demonstrated considerable profitability, although they occupied smaller cultivated areas. Conversely, crops like pigeon peas (4.1%), potatoes (7.6%), and sweet potatoes (7.6%) exhibited the lowest profit margins, which may discourage farmers from investing in them unless other incentives, such as ecological benefits or local consumption needs, are present. Regarding the results, we therefore recommend to promote policies supporting agroforestry, improve market access and develop infrastructure to exploit these benefits. 展开更多
关键词 OPTIMIZATION land Use Crop Productivity AGROFORESTRY Smallholder Farmers BURUNDI
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Modeling the Conversion of Forest Land to Other Types of Occupation Due to Urban Growth in Five Forest Towns in the Congo Basin
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作者 Stoffenne Malonga Binsangou Suspense Averti Ifo Benoit Mertens 《Open Journal of Ecology》 2025年第1期43-64,共22页
The conversion of forest land to other types of land cover is one of the major issues in the global fight against climate change. Understanding the direct and indirect factors of these conversions from local studies i... The conversion of forest land to other types of land cover is one of the major issues in the global fight against climate change. Understanding the direct and indirect factors of these conversions from local studies in the tropics is essential to project the future impact of human activities on the preservation of tropical forests in general and the forests of the Republic of Congo in particular. This study, conducted in five localities with different socioeconomic contexts in the Republic of Congo, aims to analyze the variability of drivers of deforestation and forest degradation linked to urbanization in the Congo Basin. Using a series of land cover maps from the years 1986, 2003 and 2019 for the cities of Ouesso, Pokola, Ngombe, Impfondo and Dongou, as well as field data and socio-economic information collected from local and central administrations, a unique model has been developed to understand the explanatory patterns of forest loss. Deforestation around urban centers is mainly due to urban agriculture due to population growth, as well as the spatial expansion of cities, which have a major impact on the stability and integrity of forests. Shifting agriculture is the main direct cause of deforestation and forest degradation, representing 48% of the total sample, followed by the collection of wood fuel (22%), the collection of construction wood (19%), illegal logging (6%) and urban expansion (5%). Forecasts indicate that forest loss around major cities will increase by 487, 20 ha to 5266, 73 ha by 2050 compared to the base year of 2019. This study highlights the need for a new system of land management and poverty alleviation of local populations to ensure the stability of the Congo Basin tropical forests around large and small African cities. 展开更多
关键词 DEFORESTATION Degradation MODELING Congo Basin land Use Change landSAT Strong Points
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Use of a Land Use Regression Model Methodology for the Estimation of Individual Long-Term PM2.5 Exposure Profiles of Urban Residents in Jiujiang City, China
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作者 Weiye Wang Sisi Hu 《Journal of Geoscience and Environment Protection》 2025年第1期233-243,共11页
The purpose of this study was to establish a method able to accurately estimate the long-term exposure levels of individuals to fine particulate matter (PM2.5) in Jiujiang City (China) by constructing land use regress... The purpose of this study was to establish a method able to accurately estimate the long-term exposure levels of individuals to fine particulate matter (PM2.5) in Jiujiang City (China) by constructing land use regression (LUR) models. Subsequently, the accuracy of models was further verified. PM2.5 concentrations were continuously collected daily from seven monitoring stations for the construction of daily LUR models from September 1 to 14, 2023. The constructed models used PM2.5 concentrations as the dependent variable, while land use, elevation, population density and road length were used as the predictive variables. Subsequently, twenty volunteers were invited to participate, with their daily PM2.5 exposure estimated based on their work address and home address, allowing their average exposure levels to be calculated. Furthermore, volunteers wore portable PM2.5 detectors continuously for a 14-day period and the average measured PM2.5 level was used as a comparative standard. Results showed that the adjusted R2 values for the 14 daily models ranged from 0.85 to 0.94, with the R2 values generated from leave-one-out-cross-validation tests all greater than 0.61, indicating good prediction accuracy. No significant differences were observed in the measurement accuracy of the LUR modeling method and measurements using a portable PM2.5 detector (p > 0.05). This study aimed to develop a novel method for the accurate and convenient measurement of individual long-term PM2.5 exposure levels for epidemiological studies in urban environments comparable to that of Jiujiang city. 展开更多
关键词 land Use Regression Fine Particulate Matter PM2.5 Individual Exposure Long-Term Exposure
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结合RF和LandTrendr算法的黄河流域下游撂荒耕地提取与时空变化分析
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作者 郭益梦 何珊 邵怀勇 《农业工程学报》 北大核心 2025年第2期271-280,共10页
耕地撂荒是一种常见的土地利用与覆被变化现象,深刻影响着全球的农业生产和粮食安全。黄河流域作为中国重要的粮食生产基地,监测其撂荒耕地时空动态变化并分析其原因具有重要的现实意义。该研究以黄河流域下游兰考县、长垣市、封丘县和... 耕地撂荒是一种常见的土地利用与覆被变化现象,深刻影响着全球的农业生产和粮食安全。黄河流域作为中国重要的粮食生产基地,监测其撂荒耕地时空动态变化并分析其原因具有重要的现实意义。该研究以黄河流域下游兰考县、长垣市、封丘县和东明县为研究区,依托Google Earth Engine(GEE)云平台,结合Landsat长时间序列影像,并通过分层随机采样与目视解译相结合的方式构建样本集,结合多维度特征,综合应用随机森林概率模型及LandTrendr变化检测方法,系统地提取2004—2022年撂荒耕地与休耕地,并对其动态变化进行深入分析。结果表明:1)基于土地覆被变化提取2022年撂荒耕地与非撂荒耕地的F1分数分别为0.80和0.87,而结合变化检测方法提取2004—2022年撂荒耕地,撂荒耕地与非撂荒耕地的平均F1分数分别达到0.87和0.89,精度显著提升;2)研究区撂荒耕地面积在2004—2022年间呈现先上升后波动式下降的趋势,平均面积为28.24 km^(2),2007年达到峰值49.35 km^(2),而休耕地分布零散且面积较小;3)农业机械化水平的提升有效遏制了撂荒现象,而粮食产量的提升可能会带来撂荒风险的增加,第一产业就业人数对撂荒影响有限。该研究通过结合随机森林与LandTrendr算法,实现了对撂荒耕地的精准提取,并揭示其变化趋势及影响因素,这为黄河流域下游制定针对性的农业政策,保障国家粮食安全提供了参考。 展开更多
关键词 黄河流域 耕地撂荒 粮食安全 时空变化
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Exploring Cyber Threat Intelligence into Land Administration Systems for Enhanced Cyber Resilience
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作者 Pierre-François Blin Trias Aditya +1 位作者 Purnama Budi Santosa Christophe Claramunt 《Journal of Geographic Information System》 2025年第1期45-65,共21页
The current global cybersecurity landscape, characterized by the increasing scale and sophistication of cyberattacks, underscores the importance of integrating Cyber Threat Intelligence (CTI) into Land Administration ... The current global cybersecurity landscape, characterized by the increasing scale and sophistication of cyberattacks, underscores the importance of integrating Cyber Threat Intelligence (CTI) into Land Administration Systems (LAS). LAS services involve requests and responses concerning public and private cadastral data, including credentials of parties, ownership, and spatial parcels. This study explores the integration of CTI in LAS to enhance cyber resilience, focusing on the unique vulnerabilities of LAS, such as sensitive data management and interconnection with other critical systems related to spatial data uses and changes. The approach employs a case study of a typical country-specific LAS to analyse structured vulnerabilities and their attributes to determine the degree of vulnerability of LAS through a quantitative inductive approach. The analysis results indicate significant improvements in identifying and mitigating potential threats through CTI integration, thus enhancing cyber resilience. These findings are crucial for policymakers and practitioners to develop robust cybersecurity strategies for LAS. 展开更多
关键词 Cyber Threat Intelligence Common Vulnerabilities and Exposures Geodata land Administration Systems Risk Assessment Spatial Cadastral Data
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Modelling Land Degradation (LD) Using Geospatial Techniques for Agricultural and Environmental Management Case Study: Alla Catchment;Dekemhare-Eritrea
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作者 Okbaldet Negede Faith Njoki Karanja 《Journal of Geographic Information System》 2025年第1期97-117,共21页
Eritrea faces significant environmental and agricultural challenges due to human activities, rugged terrain, and fluctuating climates like recurrent droughts and erratic rainfall. Desertification, deforestation, and s... Eritrea faces significant environmental and agricultural challenges due to human activities, rugged terrain, and fluctuating climates like recurrent droughts and erratic rainfall. Desertification, deforestation, and soil erosion are major concerns affecting soil quality, water resources, and vegetation, especially in areas like the Alla catchment. Recent assessments reveal declining vegetation and precipitation levels over four decades, alongside rising temperatures, linked to increased desertification and land degradation driven by climate variations and prolonged droughts. The urgent need for sustainable land management practices is explained by reduced productivity, biodiversity, and ecosystem health. This study focused on modelling land degradation in Eritrea’s Alla catchment using advanced geospatial techniques. Vegetation indices and soil erosion models were used to evaluate critical factors such as rainfall Erosivity, soil erodibility, slope characteristics, and land cover management. The resulting model highlighted varying levels of susceptibility to land degradation, highlighting widespread vulnerability characterized by high and very high susceptibility hotspots. Areas with minimal degradation were found in the northern vegetation-covered regions. Soil loss in the catchment is primarily influenced by inadequate land cover, steep slopes, soil erosion susceptibility, erosive rainfall patterns, and insufficient support practices. The study underscores the urgency of addressing deforestation and unsustainable agricultural practices to mitigate soil erosion. Recommendations include enhancing community capacity for effective land management, promoting climate adaptation strategies, and aligning national efforts with the global Sustainable Development Goals to achieve Land Degradation Neutrality. 展开更多
关键词 Alla Catchment Remote Sensing Google Earth Pro NDVI LULC land Degradation Sustainable Development Goals Soil Erosion Susceptibility Map
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LandEM模式的改进及在青藏高原地区初步应用
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作者 刘勇洪 翁富忠 +6 位作者 何文英 唐飞 李锐 徐永明 韩阳 杨俊 王艺丹 《气象学报》 北大核心 2025年第1期61-79,共19页
基于物理模型的微波发射率(MLSE)模拟一直面临着很大挑战,目前还缺乏利用物理模式模拟较高分辨率的全球或区域尺度MLSE的应用案例。针对先进辐射传输模拟系统(ARMS)中的陆面微波发射率(LandEM)模式,对土壤介电常数和粗糙地表反射率模型... 基于物理模型的微波发射率(MLSE)模拟一直面临着很大挑战,目前还缺乏利用物理模式模拟较高分辨率的全球或区域尺度MLSE的应用案例。针对先进辐射传输模拟系统(ARMS)中的陆面微波发射率(LandEM)模式,对土壤介电常数和粗糙地表反射率模型进行了改进及相应MLSE模拟研究,并结合地面观测MLSE资料进行了模拟评估,同时开展了LandEM模式主要输入参数优化研究;在此基础上,以青藏高原地区为例,选择3种粗糙地表反射率半经验模型和1种发射率经验模型组合成9种MLSE模拟方案,利用3套卫星观测资料反演的MLSE产品,对9种不同模拟方案进行了评估,并选择出最优模拟方案对青藏高原地区MLSE进行了模拟分析。研究结果显示:LandEM模式中引入Mironov常温土壤介电常数模型后模拟的MLSE得到改善,引入Zhang冻土介电常数模型可弥补原有冻土介电常数估算的缺陷,引入Chen-Weng粗糙地表反射率模型后模拟的MLSE也得到有效改善;针对青藏高原地区MLSE模拟,Qp粗糙地表反射率模型更适合裸土粗糙地表,Chen-Weng模型更适合植被粗糙地表;改进后的LandEM模式及优化模拟方案能较好地模拟0.10°×0.10°空间分辨率青藏高原地区水平极化MLSE值及空间分布,也能较好地模拟垂直极化MLSE值,但还不能对垂直极化MLSE空间差异进行有效模拟。 展开更多
关键词 微波地表发射率 landEM模式 土壤介电常数 粗糙地表反射率 青藏高原
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