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Tree species determine soil seed bank composition and its similarity with understory vegetation in a semi-arid African savanna

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Ecological Processes 2017年第1期6卷 84-99页

作者： Zewdu Kelkay Tessema Belay Ejigu Lisanework Nigatu Rangeland Ecology and Biodiversity Program School of Animal and Range SciencesCollege of Agriculture and Environmental SciencesHaramaya UniversityPO Box 138Dire DawaEthiopia department of Animal Sciences Faculty of AgricultureWollega UniversityPO Box 38Shambu CampusEthiopia School of natural resource management and environmental Sciences College of Agriculture and Environmental SciencesHaramaya UniversityPO Box 138Dire DawaEthiopia

Introduction:The presence of larger trees in semi-arid African savannas creates sub-habitats,which influences on herbaceous plant communities grown under their canopies differently from opened *** of seed banks accumulated in the soils over time beneath larger trees could facilitate the recovery of plant communities that might disappear due to sustained heavy grazing,prolonged fire,or other anthropogenic factors in semi-arid African ***,the impact of larger trees on soil seed bank composition and its similarity with plant communities grown under their canopies are less understood in semi-arid African ***,we studied the effect of leguminous and non-leguminous tree species and their canopies on soil seed bank(SSB)composition and its similarity with understory vegetation(USV)in a semi-arid savanna of ***:We selected 20 matured trees from 3 dominant tree species,representing one leguminous(Acacia robusta Burch)and 2 non-leguminous tree species(Ziziphus spina-Christi and Balanites aegyptiaca(L.)Del),found in isolation,a total of 60 trees for this *** each selected individual tree,the species composition of USV were recorded using 1-m2 quadrat in four directions(north,south,east,and west)under the inside and outside tree canopies during the flowering ***,soil samples in a 1-m2 quadrat were also collected under the inside tree canopies and their corresponding outside canopies,in each individual tree,for the determination of SSB composition,using a seed emergence ***,the soil was thoroughly mixed after removal of all roots and plant fragments,and spread over sand in plastic pots to a depth of 20 *** pots were placed at random in a glasshouse,examined every 3 days,for the first 2 months,and thereafter weekly for 6 months.A total of 960 soil samples were used for the determination of SSB composition during this ***:A total of 64 species were emerged from the SSB samples,of which 27 w

关键词： Functional groups Herbaceous layers Plant abundance Seedling density Species composition Species diversity Tree-grass interaction

Paving the way toward soil safety and health:current status,challenges,and potential solutions

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Frontiers of environmental Science & Engineering 2024年第6期18卷 63-73页

作者： Chiheng Chu Lizhong Zhu College of environmental and resource Sciences Zhejiang UniversityHangzhou 310058China

Soil is a non-renewable resource,providing a majority of the world’s food and fiber while serving as a vital carbon ***,the health of soil faces global threats from human activities,particularly widespread contamination by industrial *** physical,chemical,and biological remediation approaches encounter challenges in preserving soil structure and function throughout the remediation process,as well as addressing the complexities of soil contamination on a regional *** solutions encompass monitoring and simulating soil processes,with a focus on utilizing big data to bridge micro-scale and macro-scale ***,reducing pollutant emissions to soil is paramount due to the significant challenges associated with removing contaminants once they have entered the soil,coupled with the high economic costs of ***,it is imperative to implement advanced remediation technologies,such as monitored natural attenuation,and embrace holistic soil management approaches that involve regulatory frameworks,soil health indicators,and soil safety monitoring *** the enduring health and resilience of soils necessitates a blend of interdisciplinary research,technological innovation,and collaborative initiatives.

关键词： Soil safety and health Source emission reduction Process monitoring and simulation Green remediation technology Soil health management

Adsorption behavior of imidacloprid pesticide on polar microplastics under environmental conditions:critical role of photo-aging

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Frontiers of environmental Science & Engineering 2023年第4期17卷 13-26页

作者： Weiyi Liu Ting Pan Hang Liu Mengyun Jiang Tingting Zhang department of environmental Science and Engineering Research Centre for Resource and EnvironmentBeijing University of Chemical TechnologyBeijing 100029China

The photo-aging behavior of microplastics(MPs)in natural environment has become a global *** ultraviolet radiation has enough energy to change the polymer structure and physicalchemical properties of *** attention has focused on the interactions of the photo-aged polar and biodegradable MPs with organic *** work investigated the structural properties of aged polar polyamide(PA)MPs and biodegradable polylactic acid(PLA)MPs exposed to ultraviolet irradiation and their adsorption behavior and mechanism for neonicotinoid insecticide imidacloprid(IMI).The results showed that the MPs had extensive changes in surface morphology and chemical properties after *** C–N bond of PA MPs was disrupted to form more carbonyl *** oxygen-containing functional groups on the surface of aged PLA MPs were broken and generated relatively smaller *** adsorption capacity of IMI on PA MPs decreased by 19.2%,while the adsorption capacity of IMI on PLA MPs increased by 41.2%after *** depended on the natural structure of the MPs and their ability to absorb ultraviolet *** electrostatic interactions,hydrogen bonds,van der Waals interactions,and polar-polar interactions were the main adsorption mechanisms of IMI on *** initial solution pH and low ionic strength favored the adsorption of IMI by altering charge distribution on the MPs *** formation of the humic acid-IMI complexes decreased the concentration of IMI in the water phase and further decreased the adsorption on *** results are enlightening for a scientific comprehension of the environmental behavior of the polar MPs.

关键词： Microplastics Neonicotinoid insecticide Photo-aging adsorption environmental conditions

Digital Soil Mapping Using Artificial Neural Networks and Terrain-Related Attributes

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Pedosphere 2015年第4期25卷 580-591页

作者： Mohsen BAGHERI BODAGHABADI José Antonio MARTINEZ-CASASNOVAS Mohammad Hasan SALEHI Jahangard MOHAMMADI Isa ESFANDIARPOOR BORUJENI Norair TOOMANIAN Amir GANDOMKAR department of Geography Najafabad Branch Islamic Azad University department of environmental and Soil Science University of Lleida department of Soil Science College of Agriculture Shahrekord University department of Soil Science College of Agriculture Vali-e-Asr University Agriculture and natural resource Research Center

Detailed soil surveys involve costly and time-consuming work and require expert knowledge. Since soil surveys provide information to meet a wide range of needs, new methods are necessary to map soils quickly and accurately. In this study, multilayer perceptron artificial neural networks(ANNs) were developed to map soil units using digital elevation model(DEM) attributes. Several optimal ANNs were produced based on a number of input data and hidden units. The approach used test and validation areas to calculate the accuracy of interpolated and extrapolated data. The results showed that the system and level of soil classification employed had a direct effect on the accuracy of the results. At the lowest level, smaller errors were observed with the World Reference Base(WRB)classification criteria than the Soil Taxonomy(ST) system, but more soil classes could be predicted when using ST(7 soils in the case of ST vs. 5 with WRB). Training errors were below 11% for all the ANN models applied, while the test error(interpolation error) and validation error(extrapolation error) were as high as 50% and 70%, respectively. As expected, soil prediction using a higher level of classification presented a better overall level of accuracy. To obtain better predictions, in addition to DEM attributes, data related to landforms and/or lithology as soil-forming factors, should be used as ANN input data.

关键词： digital elevation model attributes multilayer perceptron soil classification soil-forming factors soil survey

Effects of acid deposition control in China:a review based on responses of subtropical forests

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Frontiers of environmental Science & Engineering 2024年第6期18卷 115-126页

作者： Danni Xie Xiaodong Ge Lei Duan Jan Mulder School of Land Engineering Chang’an UniversityXi’an 710064China State Key Laboratory of environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China State environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China Faculty of environmental Sciences and natural resource management Norwegian University of Life SciencesBox 5003NO-1432ÅsNorway

For many decades,acid deposition used to pose a significant regional air pollution challenge in *** substantial emission control of anthropogenically derived sulfur and nitrogen containing gasses,both sulfur and nitrogen deposition,as well as the acid rain-affected area,have significantly decreased compared to their peak ***,particularly in the humid subtropics,are sensitive to acid deposition,as evidenced by soil acidification,sulfate and nitrate leaching in stream water,and elevated soil nitrous oxide *** in the total deposition of sulfur and nitrogen,caused a significant decline in sulfate and nitrate leaching from subtropical forest and subsequently in sulfate and nitrate concentrations in stream water,although there was about a 5-year *** delay may be attributed to the desorption of accumulated sulfate and continued elevated mineralization of accumulated nitrogen *** of nitrous oxide,a potent greenhouse gas,also declined in nitrogen-saturated subtropical forest soils,as soil water nitrate concentration ***,subtropical forests in China suffering from elevated acid deposition have begun to ***,the current levels of sulfur and nitrogen deposition continue to exceed the critical loads,i.e.,the assigned threshold levels in accordance with emission control policies,in more than 10%of the country’s land area,respectively,indicating remaining risks of acidification and ***,further emission reductions are urgently needed,also because they will help achieving goals related to air quality and nitrous oxide emissions.

关键词： Acidification Critical load Nitrous oxide Surface water chemistry Recovery

World Regionalization of Climate Change(1961–2010)

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International Journal of Disaster Risk Science 2016年第3期7卷 216-226页

作者： Peijun Shi Shao Sun Daoyi Gong Tao Zhou State Key Laboratory of Earth Surface Processes and resource Ecology Beijing Normal University Key Laboratory of environmental Change and natural Disasters of Ministry of Education Beijing Normal University Academy of Disaster Reduction and Emergency management Ministry of Civil Affairs & Ministry of Education

Traditional climate classification or regionalization characterizes the mean state of climate condition, which cannot meet the demand of addressing climate change currently. We have developed a climate change classification method, as well as the fundamental principles, an indicator system, and mapping techniques of climate change regionalization. This study used annual mean temperature and total precipitation as climatic indices, and linear trend and variation change as change indices to characterize climate change quantitatively. The study has proposed a scheme for world climate change regionalization based on a half century of climate data(1961–2010). Level-I regionalization divides the world into 12 tendency zones based on the linear trend of climate, level-II regionalization resulted in 28 fluctuation regions based on the variation change of climate. Climate change regionalization provides a scientific basis for countries and regions to develop plans for adapting to climate change, especially for managing climate-related disaster or environmental risks.

关键词： Climate change Regionalization Temperature Precipitation Tendency Fluctuation World

Vegetation Mapping of the Mond Protected Area of Bushehr Province(South-west Iran)

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Journal of Integrative Plant Biology 2009年第3期51卷 251-260页

作者： Ahmadreza Mehrabian Alireza Naqinezhad Abdolrassoul Salman Mahiny Hossein Mostafavi Homan Liaghati Mohsen Kouchekzadeh department of Biodiversity and Ecosystems management Environmental Sciences Research InstituteShahid Beheshti University department of Biology Faculty of SciencesUniversity of Mazandaran College of the Environment Gorgan University of Agriculture and Natural Resources Sciences department of Ecological Agriculture Environmental Sciences Research InstituteShahid Beheshti University department of Planning and Design of Environment Environmental Research InstituteShahid Beheshti University

Arid regions of the world occupy up to 35% of the earth＇s surface, the basis of various definitions of climatic conditions, vegetation types or potential for food production. Due to their high ecological value, monitoring of arid regions is necessary and modern vegetation studies can help in the conservation and management of these areas. The use of remote sensing for mapping of desert vegetation is difficult due to mixing of the spectral reflectance of bright desert soils with the weak spectral response of sparse vegetation. We studied the vegetation types in the semiarid to arid region of Mond Protected Area, south-west Iran, based on unsupervised classification of the Spot XS bands and then produced updated maps. Sixteen map units covering 12 vegetation types were recognized in the area based on both field works and satellite mapping. Halocnemum strobilaceum and Suaeda fruticosa vegetation types were the dominant types and Ephedra foliata, Salicornia europaea-Suaeda heterophylla vegetation types were the smallest. Vegetation coverage decreased sharply with the increase in salinity towards the coastal areas of the Persian Gulf. The highest vegetation coverage belonged to the riparian vegetation along the Mond River, which represents the northern boundary of the protected area. The location of vegetation types was studied on the separate soil and habitat diversity maps of the study area, which helped in final refinements of the vegetation map produced.

关键词： arid region coast line halophytes island vegetation Iran Persian Gulf vegetation mapping vegetation types.

Evaluation of land suitability for Moringa oleifera tree cultivation by using Geospatial technology:The case of Dhidhessa Catchment,Abay Basin,Ethiopia

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Oil Crop Science 2023年第1期8卷 45-55页

作者： Mitiku Badasa Moisa Muleta Ebissa Feyissa Indale Niguse Dejene Firdissa Sadeta Tiye Kiros Tsegay Deribew Zenebe Reta Roba Mengistu Muleta Gurmessa Dessalegn Obsi Gemeda department of Agricultural Engineering Faculty of TechnologyWollega University Shambu CampusEthiopia department of Earth Sciences College of Natural and Computational SciencesWollega University Nekemte CampusNekemteEthiopia department of Geography and environmental Studies Wollega UniversityGimbi CampusGimbiEthiopia department of Geography and environmental Studies Raya UniversityMaichewEthiopia department of Forestry College of Natural Resource and Agricultural EconomicsMettu University Bedele CampusEthiopia department of Fisheries and Aquatic Sciences Faculty of AgricultureWollega University Shambu CampusShambuEthiopia department of natural resource management College of Agriculture and Veterinary MedicineJimma UniversityEthiopia

Land suitability analysis of Moringa oleifera tree cultivation is important to enhance its product,as the demand forthis tree for medicinal values and food sources is increasing ***,this study aimed to assess suitableland for Moringa oleifera tree cultivation by using the integration of multi-criteria evaluation with geospatialtechnologies in the Dhidhessa catchment,western *** parameters,namely:slope,land use and landcover(LULC),soil texture,land surface temperature,and rainfall data,were used in this *** land suitabilityevaluation of Moringa oleifera is classified into three classes as highly suitable,moderately suitable,and *** results revealed that,about 344.4 km2(12.2%)of the area is categorized into highly suitable,and2343.7 km2(83%)is moderately suitable for Moringa tree,whereas,137.2 km2(4.9%)is categorized as notsuitable for Moringa oleifera tree ***,based on the finding of the study,we suggested that farmers andother stakeholders can cultivate Moringa oleifera trees in the Dhidhessa catchment.

关键词： Moringa tree Medicinal plant Overlay analysis AHP MCE

Farmers' contributions to the conservation of tree diversity in the Groundnut Basin,Senegal

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Journal of Forestry Research 2017年第5期28卷 1083-1096页

作者： Antoine Sambou Bienvenu Sambou Anders R?bild department of Geosciences and natural resource management Faculty of ScienceUniversity of Copenhagen Institut des Sciences de l'Environnement (ISE) Facultdes Sciences et TechniqueUniversitCheikh Anta Diop(UCAD)

Tree diversity in West Africa is threatened by intensified land uses and salinization, and farmers’ role in conservation of tree species is unclear. We hypothesized that farmers contribute to conservation of tree diversity through protection of trees in their agroforestry landscapes and compared the diversity and structure of the tree vegetation across landscape classes. Inventories were carried out in three villages in the Groundnut Basin in Senegal, assessing tree diversity, density and crown cover. Tree diversity as assessed by species accumulation curves was high in forests, but cultivated landscapes had comparable or almost comparable diversity, especially in the cases where the forest was planted or was affected by charcoal production. However, the occurrence of exotic species was higher in cultivated parts of the landscape, and although many species were in common, ordination plots indicated that forests and cultivated landscapes to some degree had different species composition. Salinity had a strong influence on vegetation, not only in the tans (salt marshes) but also across the other landscape classes. In conclusion, agroforestry landscapes in the three villages harbor considerable tree diversity, but insufficient to fully conserve the tree species. We argue that informing and including farmers in tree management in the region will contribute to overall conservation of tree genetic resources.

关键词： Tree diversity Conservation-landscape classes environmental factors Groundnut Basin