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Modeling of maize gross primary production using MODIS imagery and flux tower data

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International Journal of Agricultural and Biological Engineering 2016年第2期9卷 110-118,I0004,I0005页

作者： Li Shihua He Ping Liu Baosheng Ni Ping Han Xing school of resources and environment University of Electronic Science and Technology of ChinaChengdu 611731China school of resources and environment Jilin Agricultural UniversityChangchun 130018China

Maize is one of the most important crops cultivated on the global *** estimation of maize Gross Primary Production(GPP)can provide valuable information for regional and global carbon budget *** site level to regional/global scales,GPP estimation depends on remote sensing or eddy covariance flux *** this research,the 8-day composite GPP of maize was estimated by Moderate Resolution Imaging Spectroradiometer(MODIS)and flux tower data at eight study sites using a Regional Production Efficiency Model(REG-PEM).The performance of the model was assessed by analyzing the linearly regression of GPP estimated from the REG-PEM model(GPPEST)with the GPP predicted from the eddy covariance data(GPPEC).The coefficient of determination,root mean squared error and mean absolute error of the regression model were *** uncertainties of the model are also discussed in this *** seasonal dynamics(phases and magnitudes)of the GPPEST reasonably agreed with those of GPPEC,indicating the potential of the satellite-driven REG-PEM model for up-scaling the GPP in maize ***,the maize GPP estimated by this model is more accurate than the MODIS GPP products(MOD17A2).In particular,MOD17A2 significantly underestimated the GPP of maize *** uncertainties in the REG-PEM model are mostly contributed by the maximum light use efficiency and the fraction of photosynthetically active radiation.

关键词： gross primary production maize light use efficiency MODIS remote sensing flux datagross primary production maize light use efficiency MODIS remote sensing flux data

Intra-Oceanic Subduction of the Paleo-Asian Oceanic Slab: New Evidence from the Early Carboniferous Quartz Diorite in the Diyanmiao Ophiolite

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Acta Geologica Sinica(English Edition) 2020年第2期94卷 565-567页

作者： WANG Jinfang LI Yingjie LI Hongyang DONG Peipei school of natural resources Hebei Geo UniversityShijiazhuang 050031China

Late Paleozoic supra-subduction zone(SSZ)-type ophiolites and intra-oceanic arc igneous petrotectonic assemblages are developed in the Erenhot-Hegenshan suture zone(EHSZ)in the eastern part of the Central Asian Orogenic Belt(CAOB).which contains information about the Late Paleozoic tectonic evolution of the Paleo-Asian Ocean(PAO)in the eastern ***,there are two main views and associated controversies about the closure time of the PAO in the eastern CAOB,which are“collision suture from Late Devonian to Early Carboniferous”and“final suture from Late Permian to Early Triassic”.

关键词： Carboniferous Asian suture

Ammonia removal from low-strength municipal wastewater by powdered resin combined with simultaneous recovery as struvite

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Frontiers of environmental Science & Engineering 2021年第1期15卷 125-134页

作者： Kuo Fang Fei Peng Hui Gong Huanzhen Zhang Kaijun Wang State Key Joint Laboratory of environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China school of Water resources&environment China University of GeosciencesBeijing 100083China

Low-strength municipal wastewater is considered to be a recoverable nutrient resource with economic and environmental ***,various technologies for nutrient removal and recovery have been *** this paper,powdered ion exchange resin was employed for ammonia removal and recovery from imitated low-strength municipal *** effects of various working conditions(powdered resin dosage,initial concentration,and pH value)were studied in batch experiments to investigate the feasibility of the approach and to achieve performance *** maximum adsorption capacity determined by the Langmuir model was 44.39 mg/g,which is comparable to traditional ion exchange ***,the effects of co-existing cations(Ca^(2+),Mg^(2+),K^(+))were *** on the above experiments,recovery of ammonia as struvite was successfully achieved by a proposed two-stage crystallization process coupled with a powdered resin ion exchange *** electron microscopy(SEM)and X-ray diffractometry(XRD)results revealed that struvite crystals were successfully gained in alkaline conditions(pH=10).This research demonstrates that a powdered resin and two-stage crystallization process provide an innovative and promising means for highly efficient and easy recovery from low-strength municipal wastewater.

关键词： Ammonia removal and recovery Powdered resin Crystallization process Struvite Co-existing cations

Water and heat transport in hilly red soil of southern China:II. Modeling and simulation

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2005年第5期6卷 338-345页

作者：吕军黄志珍韩晓非 school of environmental Science and natural resources Zhejiang University Hangzhou 310029 China

Simulation models of heat and water transport have not been rigorously tested for the red soils of southern China. Based on the theory of nonisothermal water-heat coupled transfer, a simulation model, programmed in Visual Basic 6.0, was developed to predict the coupled transfer of water and heat in hilly red soil. A series of soil column experiments for soil water and heat transfer, including soil columns with closed and evaporating top ends, were used to test the simulation model. Results showed that in the closed columns, the temporal and spatial distribution of moisture and heat could be very well predicted by the model, while in the evaporating columns, the simulated soil water contents were somewhat different from the observed ones. In the heat flow equation by Taylor and Lary (1964), the effect of soil water evaporation on the heat flow is not involved, which may be the main reason for the differences between simulated and observed results. The predicted temperatures were not in agreement with the observed one with thermal conductivities calculated by de Vries and Wierenga equations, so that it is suggested that Kh, soil heat conductivity, be multiplied by 8.0 for the first 6.5 h and by 1.2 later on. Sensitivity analysis of soil water and heat coefficients showed that the saturated hydraulic conductivity, KS, and the water diffusivity, D(θ), had great effects on soil water transport; the variation of soil porosity led to the difference of soil thermal properties, and accordingly changed temperature redistribution, which would affect water redistribution.

关键词： Red soil Coupled transfer of soil water and heat Simulation model Validation Sensitivity analysis

Recovery of Baikiaea forest of southwestern Zambia from shifting cultivation and its implications for sustainable management

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Journal of Forestry Research 2019年第2期30卷 497-506页

作者： Filipo Zulu Stephen Syampungani Peter Fushike National Science and Technology Council (NSTC) school of natural resources Copperbelt University

We studied the dominant species by age category of re-growth, and how subsistence forest use through shifting cultivation impacted on the floristic composition of Baikiaea forest. For re-growth stands, variable sampling method was adopted in data collection while in mature stands, a sample plot size of 50 m 9 50 m was used at each of three study sites. Distribution of species by age categories showed that shrub, herb, and grass species were abundant in young re-growth stands while woody vegetation became common with increasing age of the re-growth stand. Hierarchical clustering for common woody species showed several species associations with age categories and also with relatively undisturbed woodland. Common regeneration mechanisms of key woody species were mainly by seed(48%), coppicing(40%) and root suckers(12%). The young re-growth stands of 6–10 and 11–15 years were characterized by B. petersiana, ***, Combretum zeyheri, and Guibourtia coleosperma. Older stands(16–20 years after abandonment) were characterized by B. plurijuga, Pterocarpus antunesii, and Baphia massiensis, thus closely mimicking the relatively undisturbed forest whose dominant key woody species were B. plurijuga, P. antunesii, and G. coloesperma. There were many stems in younger stands(2–5 years) and fewer stems in older re-growth stands of 16–20 years after abandonment following shifting cultivation. Older regrowth stands(16–20 years) were similar to undisturbed stands(P \ 0.005). The similarity between re-growth stands of 16–20 years and control stands demonstrates the recovery of Baikiaea forest over time after cessation of shifting agriculture. Baikiaea forest requires some disturbance to perpetuate the dominant species and begins to show signs of recovery from shifting cultivation within16–20 years after abandonment. This is contrary to assertions that this ecosystem could take up to about 100 years for abandoned fields to begin showing signs of

关键词： Regeneration dynamics Species diversity Tree species dominance Management model Shifting cultivation

Electrochemical corrosion of steel balls in wet grinding

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中国有色金属学会会刊：英文版 2003年第4期13卷 958-962页

作者：谢恒星李松仁李定或 College of Resource and environment Engineering school of resources Processing and Bioengineering Department of Mineral Engineering

Rest potentials for the steel ball electrode and the pyrite electrode as well as the combination potentials and the galvanic currents developed in the pyrite steel ball couple were measured. The data demonstrate that the galvanic couples are going to form between the pyrite particles and the steel balls when they contact with each other. The initial combination potential and the initial galvanic current of the pyrite ball couple while bubbling with oxygen are greater than those in aeration of air. The combination potential and the galvanic current decrease more quickly with time while bubbling with oxygen than they do in aeration of air. In an experiment of simulating wear differences, a galvanic current, which is smaller than that developed in the pyrite ball couple, exists between two different ball electrodes in wear degree on the surface of them. Under different grinding time conditions, the equivalent corrosion current density calculated from marked ball wear data by applying Faraday’s law correlates well with those estimated from polarization curves of pyrite and ball electrodes, and the former is always greater than the latter.

关键词：磨矿电化学腐蚀钢球球磨机选矿

Water and heat transport in hilly red soil of southern China:I. Experiment and analysis

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2005年第5期6卷 331-337页

作者：吕军黄志珍韩晓非 school of environmental Science and natural resources Zhejiang University Hangzhou 310029 China

Studies on coupled transfer of soil moisture and heat have been widely carried out for decades. However, little work has been done on red soils, widespread in southern China. The simultaneous transfer of soil moisture and heat depends on soil physical properties and the climate conditions. Red soil is heavy clay and high content of free iron and aluminum oxide. The climate conditions are characterized by the clear four seasons and the serious seasonal drought. The great annual and diurnal air temperature differences result in significant fluctuation in soil temperature in top layer. The closed and evaporating columns experiments with red soil were conducted to simulate the coupled transfer of soil water and heat under the overlaying and opening fields’ conditions, and to analyze the effects of soil temperature gradient on the water transfer and the effects of initial soil water contents on the transfer of soil water and heat. The closed and evaporating columns were designed similarly with about 18 °C temperatures differences between the top and bottom boundary, except of the upper end closed or exposed to the air, respectively. Results showed that in the closed column, water moved towards the cold end driven by temperature gradient, while the transported water decreased with the increasing initial soil water content until the initial soil water content reached to field capacity equivalent, when almost no changes for the soil moisture profile. In the evaporating column, the net transport of soil water was simultaneously driven by evaporation and temperature gradients, and the drier soil was more influenced by temperature gradient than by evapo- ration. In drier soil, it took a longer time for the temperature to reach equilibrium, because of more net amount of transported water.

关键词： Red soil Coupled transfer of water and heat Evaporation Initial soil moisture

Insect pollinator dependence of shea (Vitellaria paradoxa C.F. Gaertn.) in the Guinea Savanna zone of Ghana

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Ecological Processes 2019年第1期8卷 593-601页

作者： Latif Iddrisu Nasare Peter KKwapong Dzigbodi Adzo Doke Department of Forestry and Forest resources Management Faculty of Natural Resources and EnvironmentUniversity for Development StudiesP.O.Box TL 1882TamaleGhana Department of Conservation Biology and Entomology School of Biological SciencesCollege of Agriculture and Natural SciencesUniversity of Cape CoastCape CoastGhana Department of Eco-tourism and environmental Management Faculty of Natural Resources and EnvironmentUniversity for Development StudiesP.O.Box TL 1882TamaleGhana.

Shea(Vitellaria paradoxa ***.)is a multipurpose tree species indigenous to the Sudano Sahelian zone of Africa and occurs as the most abundant economic tree species in northern *** edible oil(shea butter)extracted from shea kernel is ranked as the most economic product of the *** fruit set and yield of shea are known to be influenced by insect pollination,the actual contribution of insect pollinators to its reproductive success has rarely been *** study estimated the percentage insect pollinator dependence and monetary value of insect pollination per bag of shea kernel(85 kg)in the Guinea savanna *** pollination and insect exclusion treatments were applied to the flowers of 18 randomly selected matured shea trees and observed from the onset of flowering to fruit *** of total production value attributed to insect pollination approach was used in estimating the monetary value of pollination per bag of shea kernel with the average market price as *** study revealed an insect pollinator dependence of 77%and 73%for fruit set and dry kernel yield,*** number of fruit set per inflorescence varied significantly between insectexcluded and open-pollinated inflorescences(p<0.05).The monetary value of insect pollination was estimated at GH₵73.21(US$18.67)per bag of kernel as of August *** is a high insect pollinator–dependent species and the conservation of insect pollinators would be critical to the sustainability of yield.

关键词： Fruit set Inflorescence Insect pollinator dependence Pollination Shea

Electrochemically induced phase transition in a nanoflower vanadium tetrasulfide cathode for high-performance zinc-ion batteries

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Journal of Energy Chemistry 2022年第6期31卷 356-362,I0010页

作者： Shizhe Gao Peng Ju Ziquan Liu Lei Zhai Wenbao Liu Xiaoyu Zhang Yanli Zhou Caifu Dong Fuyi Jiang Jianchao Sun school of environment and Material Engineering Yantai UniversityYantai 264005ShandongChina Key Laboratory of Marine Eco-environmental Science and Technology Marine Bioresource and Environment Research CenterFirst Institute of OceanographyMinistry of Natural ResourcesQingdao 266061ShandongChina

Aqueous zinc-ion batteries (AZIBs) are promising contenders for large-scale energy storage with the merits of their low cost,high safety,environmental friendliness,and competitive gravimetric energy ***,suitable cathode materials with long cycle life and adequate capacity are still ***,we report a nanoflower vanadium tetrasulfide/carbon nanotubes (VS_(4)/CNTs) cathode with high Znstorage *** propose a phase transition reaction mechanism from VS_(4)to zinc pyrovanadate in the initial cycles and a reversible intercalation mechanism for Zn^(2+) in zinc pyrovanadate during subsequent *** a result,the cathode delivers a high discharge capacity of 265 mAh g^(-1)at 0.25 A g^(-1)and 182 m Ah g^(-1)at 7 A g^(-1).In addition,the cathode exhibits a long-term cyclability with 93%capacity retention over 1200 cycles at 5 A g^(-1).VS_(4)/CNTs with superior electrochemical performance is a hopeful cathode material in AZIBs.

关键词： Zinc-ion batteries Vanadium tetrasulfide Zinc pyrovanadate Phase transition Reaction mechanism