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Mobilization and Acquisition of Sparingly Soluble P-Sources by Brassica Cultivars under P-Starved Environment I. Differential Growth Response,P-Efficiency Characteristics and P-Remobilization

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Journal of Integrative Plant Biology 2009年第11期51卷 1008-1023页

作者： Muhammad Shahbaz Akhtar Yoko Oki Tadashi Adachi Department of environmental management Engineering Faculty of Environmental Science and TechnologyThe Graduate School of Environmental ScienceOkayama University

Phosphorus （P） starvation is highly notorious for limiting plant growth around the globe. To combat P-starvation, plants constantly sense the changes in their environment, and elicit an elegant myriad of plastic responses and rescue strategies to enhance P-solublization and acquisition from bound soil P-forms. Relative growth responses, P-solublization and P- acquisition ability of 14 diverse Brassica cultivars grown with sparingly soluble P-sources （Rock-P （RP） and Ca3（PO4）2 （TCP）） were evaluated in a solution culture experiment. Cultivars showed considerable genetic diversity in terms of biomass accumulation, concentration and contents of P and Ca in shoots and roots, P-stress factor （PSF） and P use efficiency. Cultivars showed variable P-stress tolerance, and cultivars depicting low PSF and high P-efficiency values were better adaptable to P-starvation. In experiment 2, after initial feeding on optimum nutrition for 12 d after transplanting （DAT）, class-I （low P-tolerant （Oscar and Con-II）） and class-II （low P-sensitive （Gold Rush and RL-18）） cultivars were exposed to P-free environment for 25 d. All of the cultivars remobilized P from above ground parts to their roots during growth in P-free environment, the magnitude of which was variable in tested cultivars. P-concentrations （[P]s） at 37 DAT were higher in developing compared with developed leaves. Translocation of absorbed P from metabolically inactive to active sites in P- stressed plants may have helped class-I cultivars to establish a better rooting system, which provided a basis for enhanced P-utilization efficiency （PUE） and tolerance against P-stress. By supplying TCP and RP spatially separated from other nutrients in split root study, class-I cultivars were still able to mobilize RP and TCP more efficiently compared with class-II cultivars. To compare the growth behavior under P-stress, cultivars were grown in pots for 41 d after sowing, using a soil low in P （NaHCO3-extractable P = 3.97 mg/kg, Mehlich

关键词： Brassica Ca3(PO4)2 P-remobilization P-stress P-use efficiency P-stress factor rock phosphate.

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Rivers increasingly warmer:Prediction of changes in the thermal regime of rivers in Poland

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Journal of Geographical Sciences 2025年第1期 139-174页

作者： Mariusz PTAK Teerachai AMNUAYLOJAROEN Mariusz SOJKA Department of Hydrology and Water management Adam Mickiewicz University School of Energy and Environment University of Phayao Atmospheric Pollution and Climate Research Unit School of Energy and Environment University of Phayao Department of Land Improvement Environmental Development and Spatial Management Poznań University of Life Sciences

Emphasis on future environmental changes grows due to climate change, with simulations predicting rising river temperatures globally. For Poland, which has a long history of thermal studies of rivers, such an approach has not been implemented to date. This study used 9 Global Climate Models and tested three machine-learning techniques to predict river temperature changes. Random Forest performed best, with R2=0.88 and lowest error(RMSE:2.25, MAE:1.72). The range of future water temperature changes by the end of the 21st century was based on the Shared Socioeconomic Pathway scenarios SSP2-4.5 and SSP5-8.5. It was determined that by the end of the 21st century, the average temperature will increase by 2.1°C(SSP2-4.5) and 3.7°C(SSP5-8.5). A more detailed analysis, divided by two major basins Vistula and Odra, covered about 90% of Poland's territory. The average temperature increase, according to scenarios SSP2-4.5 and SSP5-8.5 for the Odra basin rivers,is 1.6°C and 3.2°C and for the Vistula basin rivers 2.3°C and 3.8°C, respectively. The Vistula basin's higher warming is due to less groundwater input and continental climate *** findings provide a crucial basis for water management to mitigate warming effects in Poland.

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The scaling relationship of leaf area and total mass of sample plots across world trees

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Journal of Forestry Research 2019年第6期30卷 2137-2142页

作者： Chengyi Tu Department of environmental Science Policy and Management University of California

The scaling relationship between leaf area and total mass of plant has important implications for understanding resource allocations in the *** model of West,Brown and Enquist(WBE model)considers that a 3/4 scaling exponent of metabolic rate versus total mass to be optimal for each plant and has been confirmed numerous *** leaf area is a better proxy of the metabolic rate than leaf mass,few studies have focused on the scaling exponent of leaf area versus total mass and even fewer have discussed the diversification of this scaling exponent across different ***,I analyzed the scaling exponent of leaf area versus total mass of sample plots across world plants.I found that as the plant grows,it allocates fewer resources to photosynthetic tissues than expected by the WBE *** results also empirically show that this scaling exponent varies significantly for different plant leaf habit,taxonomic class and geographic ***,leaf strategy in response to environmental pressure and constraint clearly plays a significant role.

关键词： Scaling relationship Leaf area Total mass Standard major axis regression

Reduction of DOM fractions and their trihalomethane formation potential in surface river water by in-line coagulation with ceramic membrane filtration

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Journal of environmental Sciences 2014年第3期26卷 529-536页

作者： Pharkphum Rakruam Suraphong Wattanachira International Postgraduate Programs in environmental management Graduate School Chulalongkorn University Center of Excellence on Hazardous Substance management Chulalongkorn University Department of environmental Engineering/Center of Excellence on Hazardous Substance management Faculty of Engineering Chiang Mai University

This research was aimed at investigating the reduction of DOM fractions and their trihalomethane formation potential （THMFP） by in-line coagulation with 0.1 μm ceramic membrane filtration. The combination of ceramic membrane filtration with a coagulation process is an alternative technology which can be applied to enhance conventional coagulation processes in the field of water treatment and drinking water production. The Ping River water （high turbidity water） was selected as the raw surface water because it is currently the main raw water source for water supply production in the urban and rural areas of Chiang Mai Province. From the investigation, the results showed that the highest percent reductions of DOC, UV-254, and THMFP （47.6%, 71.0%, and 67.4%, respectively） were achieved from in-line coagulation with ceramic membrane filtration at polyaluminum chloride dosage 40 mg/L. Resin adsorption techniques were employed to characterize the DOM in raw surface water and filtered water. The results showed that the use of a ceramic membrane with in-line coagulation was able to most efficiently reduce the hydrophobic fraction （HPOA）（68.5%）, which was then followed by the hydrophilic fraction （HPIA）（49.3%）. The greater mass DOC reduction of these two fractions provided the highest THMFP reductions （55.1% and 37.2%, respectively）. Furthermore, the in-line coagulation with ceramic membrane filtration was able to reduce the hydrophobic （HPOB） fraction which is characterized by high reactivity toward THM formation. The percent reduction of mass DOC and THMFP of HPOB by in-line coagulation with ceramic membrane filtration was 45.9% and 48.0%, respectively.

关键词： ceramic membranedissolved organic matter fractionationin-line coagulation polyaluminium chloridetrihalomethane formation potential

A long way to go:impacts of urbanization on migrants’livelihoods and rural ecology in less industrialized regions

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Journal of Mountain Science 2023年第12期20卷 3450-3463页

作者： ZHANG Zhi-qi LI Ming-jing LI Wen-jun WEI Yi-ran SHI Yi-lu Department of environmental management Peking UniversityBeijing 100871China

Urbanization,often coupled with industrialization,is generally considered as a boost for improving livelihood as well as alleviating ecological pressures of the rural ***,this experience needs to be tested in less industrialized areas,particularly where the urbanization is driven by non-economic factors such as urban public services and relevant government policies rather than employment *** two villages on the Qinghai-Tibet Plateau as examples,through the field investigation by using semi-structured questionnaires and in-depth interviews,and statistical data analysis,we explored the impacts of urbanization on migrants’livelihoods and the ecological conditions of their original village *** found that the disposable income and savings of emigrant households were less than the stay households,which might be correlated to the limited employment due to the lagged industrialization in the local township,and the mismatch between their traditional labor skills and the demands of urban *** home-village rangeland overuse was not alleviated since the increasing grazing pressure caused by the stay households,though the emigrant households intended to decrease the number of livestock on their home *** concluded that the urbanization misaligned with local industrialization may fail to improve migrant livelihoods and local ecological conditions in less industrialized *** research supplements the previous urbanization theory by highlighting the non-industrialization driven urbanization,and is particularly pertinent for the transitional countries worldwide.

关键词： Urbanization Industrialization Livelihoods Ecological conditions Pastoral areas Qinghai-Tibet Plateau

Loop-mediated isothermal amplification of single pollen grains

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Journal of Integrative Plant Biology 2014年第8期56卷 741-748页

作者： Ali Bekta Ignacio Chapela Department of environmental Science Policy and Management University of California Berkeley

The polymerase chain reaction （PCR） has been a reliable and fruitful method for many applications in ecology. Nevertheless, unavoidable technical and instrumental require- ments of PCR have limited its widespread application in field situations. The recent development of isothermal DNA amplifica- tion methods provides an alternative to PCR, which circumvents key limitations of PCR for direct amplification in the field. Being able to analyze DNA in the pollen cloud of an ecosystem would provide very useful ecological information, yet would require a field-enabled, high-throughput method for this potential to be realized. Here, we demonstrate the applicability of the loop- mediated DNA amplification method （LAMP）, an isothermal DNA amplification technique, to be used in pollen analysis. Wedemonstrate that LAMP can provide a reliable method to identify species from the pollen cloud, and that it can amplify successfully with sensitivity down to single pollen grains, thus opening the possibility of field-based, high-throughput analysis.

关键词： DNA amplification field-diagnostics loop-mediated DNAamplification method pollen

Socio-economic importance and utilization of Spondias mombin in Nigeria

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Asian Pacific Journal of Tropical Medicine 2010年第3期3卷 232-234页

作者： Adedokun MO Oladoye AO Oluwalana SA Mendie Ⅱ Department of Forestry & Wildlife management College of Environmental ManagementUniversity of Agriculture

Objective:To investigate the socio-economics and medicinal utilization of Spondia monbin, commonly known as plum in English and iyeye in ***:Three communities were selected in Abeokuta which was Itoku,Kuto,and Omida using purposive random sampling technique because of the concentration of users in the *** questionnaire was administered to randomly selected marketers,consumers and herbalists from the three *** and marketing margin were descriptively ***:The results showed that the leaves were being used for child birth aid,cough,sore throat,efu dudu,antiseptic soap,malaria and *** bark uses included child birth aid,inflammation concoction, fever,stomachic,malaria,and efu *** uses of the fruit included cure for dizziness, stomachic,eaten as food,and *** seed were also being used for child birth aid,fibroid, and *** marketing margin analyses revealed that trading on the plants was profitable with the bark having the highest margin which showed the level of its ***: The study reveals the medicinal potentials and the socioeconomic importance of Spondia mombin hence the need to conserve the species from unsustainable exploitation to ensure its availability.

关键词： Spondia mombin Trado-medical practitioners Market margin Medicinal uses Marketers

Preparation and tribological properties of lanthanum-doped TiO_2 nanoparticles in rapeseed oil

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Journal of Rare Earths 2013年第6期31卷 589-594页

作者：谷科城陈波水陈勇 Department of Oil Application & management Engineering Logistical Engineering University Department of Barracks management & environmental Engineering Logistical Engineering University

Oleic acid （denoted as OA） surface-capped lanthanum-doped titanium dioxide composite nanoparticles, abbreviated as OA/La-TiO2, were prepared via sol-gel method in association with surface modification by oleic acid. The microstructure of as-prepared OA/La-TiO2 was characterized by means of X-ray diffraction, scanning electron microscopy and Fourier transform infrared spectrometry, and their thermal stability was evaluated by thermogravimetry and differential scanning calorimetry. Moreover, the tribological properties of OA/La-TiO2 as lubricant additives in rapeseed oil were evaluated with a four-ball friction and wear tester. The morphology as well as elemental composition and chemical characteristics of worn steel surfaces was investigated by scanning electron microscopy, energy dispersive X-ray spectrometry and X-ray photoelectron spectroscopy. Results showed that as-prepared OA/La-TiO2 particles were of spherical shape and had an average diameter of 20 nm. In the meantime, OA/La-TiO2 particles doped with 1.5% （molar ratio; the same hereafter） and 2.5% of lanthanum could markedly improve the anti-wear and friction-reducing capacities of rapeseed oil. This is attributed to the formation of a complex boundary lubrication film mainly composed of the oxides of iron, titanium and lanthanum as well as the formation of an adsorption film of oleic acid on steel sliding surfaces.

关键词： titanium dioxide lanthanum nanoparticle preparation rapeseed oil lubricant additive tribological properties rare earths

Application of Basin Morphometry Laws in catchments of the south-western quadrangle of south-eastern Nigeria

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Frontiers of Earth Science 2013年第3期7卷 361-374页

作者： A.O AISUEBEOGUN I.C EZEKWE Department of Geography and environmental management Niger Delta University Wilberforce Island 560001 Nigeria Department of Geography and environmental management University of Port Harcourt Port Harcourt 500001 Nigeria

The relationship between process and form has been at the core of research in fluvial geomorphology. Form-process relationships of a natural river basin are strongly influenced by its hydrologic and sedimentologic processes as basin morphometric properties of length, shape, and relief, change in response to various hydrologic stimuli from the environment, but usually in line with well established laws. In the four fiver basins （Orashi, Otamiri, Sombreiro, New Calabar） examined in this study, however, empirical evidence does not conform neatly with theoretical postulates. Remarkable variations are noted in the molphometric properties of the catchments, when compared with established morphometric laws. The most varied in conformity are the Orashi and New Calabar basins, although the Sombreiro and Otamiri catchments also show some level of variation. Prime explanation for the morphometric and topographic non-conformity is caused by the nature of surficial material and the profoundly shallow relief of much of the study area, especially the alluvial flood and deltaic plains to the south and south-west of the study area.

关键词： catchments watershed morphology morpho- metric analysis Nigeria Africa