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Nitrogen cycling of atmosphere-plant-soft system in the typical Calamagrostis angustifolia wetland in the Sanjiang Plain,Northeast China

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Journal of Environmental Sciences 2007年第8期19卷 986-995页

作者： SUN Zhi-gao LIU Jing-shuang Northeast Institute of geography and Agricultural Ecology Chinese Academy of Sciences Changchun 130012 China. Graduate University of Chinese Academy of Sciences Beijing 100039 China Yantai Institute of Coastal Zone Research for sustainable development Chinese Academy of Sciences Yantai 264003 China

The nitrogen （N） distribution and cycling of atmosphere-plant-soil system in the typical meadow Calamagrostis angustifolia wetland （TMCW） and marsh meadow Calamagrostis angustifolia wetland （MMCW） in the Sanjiang plain were studied by a compartment model. The results showed that the N wet deposition amount was 0.757 gN/（m^2·a）, and total inorganic N （TIN） was the main body （0.640 gN/（m^2·a））. The ammonia volatilization amounts of TMCW and MMCW soils in growing season were 0.635 and 0.687 gN/m^2, and the denitrification gaseous lost amounts were 0.617 and 0.405 gN/m^2, respectively. In plant subsystem, the N was mainly stored in root and litter. Soil organic N was the main N storage of the two plant-soil systems and the proportions of it were 93.98% and 92.16%, respectively. The calculation results of N turnovers among compartments of TMCW and MMCW showed that the uptake amounts of root were 23.02 and 28.18 gN/（m^2·a） and the values of aboveground were 11.31 and 6.08 gN/（m^2·a）, the re-translocation amounts from aboveground to root were 5.96 and 2.70 gN/（m^2·a）, the translocation amounts from aboveground living body to litter were 5.35 and 3.38 gN/（m^2·a）, the translocation amounts from litter to soil were larger than 1.55 and 3.01 gN/（m^2·a）, the translocation amounts from root to soil were 14.90 and 13.17 gN/（m^2·a）, and the soil （0-15 cm） N net mineralization amounts were 1.94 and 0.55 gN/（m^2·a）, respectively. The study of N balance indicated that the two plant-soil systems might be situated in the status of lacking N, and the status might induce the degradation of C. angustifolia wetland.

关键词： compartment model nitrogen cycling Calamagrostis angustifolia wetland ecosystem Sanjiang Plain

Dynamic assembly and biocatalysis-selected gelation endow self-compartmentalized multienzyme superactivity

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Science China Chemistry 2022年第10期65卷 1985-1993页

作者： Yue Liao Xia Wang Hongdou Shen Ziyang Tai Qigang Wang school of Chemical Science and Engineering Tongji UniversityShanghai 200092China United Nations Environment Program-Tongji Institute of Environment for sustainable development Tongji UniversityShanghai 200092China

Cellular metabolism in multiple organelles utilizes compartmentalized multienzyme efficient catalysis to realize substance metabolism, energy conversion and immune defenses. The convenient and biomimetic design of artificial multienzymes has become an emerging research topic. Herein, we employ a facile enzyme-initiated radical polymerization to self-anchor multienzyme in cell-like hydrogels with mesoscale compartments. The dynamic assembly of glucose oxidase/cytochrome c(GOx/Cyt c) with methacrylate-modified hyaluronic acid can form nanoaggregates, where only the bound enzyme pairs with the adjacent position can catalyze the polymerization to compartmentalize multienzymes within hydrogel. Consequently, the cascade enzymes within hydrogel display 33.9 times higher activity compared to free enzymes, as well as excellent thermostability and multiple recyclability. The mechanism study indicates that the compartmental effect of the hydrogel and the anchoring effect of Cyt c synergistically enhance GOx/Cyt c activity. According to the density functional theory(DFT) calculation, Cyt c activity increment originates from its ligand changes of Fe(Ⅲ) porphyrin, which has a smaller energy barrier of the catalytic *** study provides a promising strategy for autonomous colocalization of multienzyme in biocompatible hydrogels which can be potentially applied in cascade enzyme induced catalysis applications.

关键词： hydrogel cascade enzyme enzymatic polymerization compartmentalization superactivity

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Plant property regulates soil bacterial community structure under altered precipitation regimes in a semi-arid desert grassland, China

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Journal of Arid Land 2023年第5期15卷 602-619页

作者： ZHANG Lihua GAO Han WANG Junfeng ZHAO Ruifeng WANG Mengmeng HAO Lianyi GUO Yafei JIANG Xiaoyu ZHONG Lingfei College of geography and Environment Science Northwest Normal UniversityLanzhou 730070China Key Laboratory of Resource Environment and sustainable development of Oasis Lanzhou 730070China College of Grassland Agriculture Northwest Agriculture and Forestry UniversityYangling 712100China

Variations of precipitation have great impacts on soil carbon cycle and decomposition of soil organic *** bacteria are crucial participants in regulating these ecological processes and vulnerable to altered *** the impacts of altered precipitation on soil bacterial community structure can provide a novel insight into the potential impacts of altered precipitation on soil carbon cycle and carbon storage of ***,soil bacterial community structure under a precipitation manipulation experiment was researched in a semi-arid desert grassland in Chinese Loess *** precipitation levels,i.e.,control,reduced and increased precipitation by 40%and 20%,respectively(referred here as CK,DP40,DP20,IP40,and IP20)were *** results showed that soil bacterial alpha diversity and rare bacteria significantly changed with altered precipitation,but the dominant bacteria and soil bacterial beta diversity did not change,which may be ascribed to the ecological strategy of soil *** linear discriminate analysis(LDA)effect size(LEfSe)method found that major response patterns of soil bacteria to altered precipitation were resource-limited and drought-tolerant *** addition,increasing precipitation greatly promoted inter-species competition,while decreasing precipitation highly facilitated inter-species *** changes in species interaction can promote different distribution ratios of bacterial populations under different precipitation *** structural equation model(SEM)analysis,with changes in precipitation,plant growth characteristics were found to be drivers of soil bacterial community composition,while soil properties were *** conclusion,our results indicated that in desert grassland ecosystem,the sensitive of soil rare bacteria to altered precipitation was stronger than that of dominant taxa,which may be related to the ecological strategy of bacteria,species interaction,and precipitation-induced var

关键词： plant-microbe interactions bacterial community diversity bacterial community composition bacterial interactions precipitation gradients

Influencing Factors and Improvement Suggestions for Agricultural Green development Performance:Empirical Insights from China

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Chinese Geographical Science 2023年第5期33卷 917-933页

作者： LI Erling ZHANG Mengzhen LI Ruolan DENG Qingqing Key Research Institute of Yellow River Civilization and sustainable development&Collaborative Innovation Center on Yellow River Civilization of Henan Province Henan UniversityKaifeng 475001China Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions/The College of geography and Environmental Science Henan UniversityKaifeng 475001China Institute of sustainable development in Agriculture and Rural Area Henan UniversityKaifeng 475004China

Agricultural green development is an essential direction for global sustainable *** academic literature,however,needs to place greater emphasis on studying the factors influencing agricultural green development performance and how such performance can be improved.A theoretical framework for agricultural green development performance was constructed in this paper using the Super-SBM model,which considers undesirable outputs,to measure the agricultural green development performance of 330 cities at or above the prefecture level in China(excluding Tibet Autonomous Region,Hong Kong,Macao and Taiwan of China)from 2007 ***,the influencing mechanism of agricultural green development performance was then analyzed using a spatial econometric *** results show that:1)from 2007 to 2018,China’s agricultural green development performance experienced three stages of evolution:‘rise,decline and rise’.2)The regions with high performance agricultural green development are mainly distributed in eastern China,northeastern China,and southern Qinghai Province.3)The agricultural economic level,industrialization process,and labor quality play significant roles in promoting local agricultural green development performance,while such performance is obviously inhibited by the openness level and the government’s environmental *** agricultural green development performance is significant inhibited by the agricultural economic level and accelerated industrialization process in neighboring cities,while significantly promoted by the agricultural industrial structure in neighboring *** suggestions for improving agricultural green development performance are proposed based on these research results,which can provide scientific references for promoting sustainable agriculture.

关键词： agricultural green development performance influencing factors improvement suggestions China

Progress of research on transportation geography in China

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Journal of Geographical Sciences 2016年第8期26卷 1067-1080页

作者：金凤君王成金曹有挥曹小曙王姣娥戴特奇焦敬娟 Key Laboratory of Regional sustainable development Modeling Institute of Geographic Sciences and Natural Resources Research CAS Nanjing Institute of geography and Limnology CAS school of geography and Planning Sun Yat-sen University school of geography Beijing Normal University University of Chinese Academy of Sciences

As an important branch of human geography, transportation geography has experienced three periods of evolution: foundation, systematization, and rapid development of the discipline. It has gradually become a relatively mature discipline. During the period 1930– 1980, the development of transportation geography consisted mainly of the publication of theoretical texts. During 1980–2000, it gradually became a systematic discipline. Since the start of the 21 st century, transportation geography has focused mainly on exploring the impacts of transportation on socio-economic development. Currently, studies on transportation geography have led to significant developments in a number of areas, including transportation theory, facility distribution and planning, transportation flows and network analysis, evaluation of transport modes, transportation planning, and simulation and assessment of urban transportation. Such studies have also enriched human geography research, provided a wider geographical overview and elucidated the development mechanism of transportation, as well as helped to understand the impacts of transport development on socio-economic systems. Some findings obtained by geographers have been widely used in transportation geography and related fields, including the four basic laws of transportation generation, the hub–spoke mode of transport organization, the subordinating and guiding functions of transportation on socio-economic development, regional transport dominance measures, accessibility measures, and spatial organization of port systems.

关键词： transportation geography evolutionary process research field academic contribution development trend

Characteristics of the dynamic changes in active accumulated temperature in Sichuan,China in the last 51 years against the background of climate change

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Journal of Mountain Science 2023年第1期20卷 115-128页

作者： WANG Hao JIANG Shan WANG Jia-bin YU Xiao-hang HUANG Jia-ning LIU Jian-gang school of geography Liaoning Normal UniversityDalian116029China

It is of utmost necessity to understand the dynamics of regional active accumulated temperature(AAT)to cope with the negative impacts of global warming on agroforestry development and food security and to provide a real-time and effective reference basis for regional agroforestry *** daily temperature data from 30 meteorological stations in Sichuan Province from 1970 to 2020,and sea surface temperature(SST)index data from the Atlantic Multiphase Oscillation(AMO)and Pacific Decadal Oscillation(PDO)were used for the *** Province was divided into the western region(WS)and the eastern region(ES),considering 1000 m above sea level as the *** spatiotemporal characteristics of≥0℃ and≥10℃ active accumulated temperature(AAT0,AAT10)in WS and ES were analyzed comprehensively using 5-day average sliding,empirical orthogonal function(EOF),ensemble empirical mode decomposition(EEMD),and multiple mutation *** results show that(1)AAT0 and AAT10 of WS ranged from 3034℃ to 3586℃ and 1971℃ to 2636℃,respectively,while the AAT0 and AAT10 of ES ranged from 5863℃ to 6513℃ and 4847℃ to 5875℃,*** period around 1997 was a significant abrupt change,and the AAT in the province generally increased during the subsequent time period(2)AAT in the study area is mainly driven by the fluctuations of AMO,as reflected by the low-to-high variation of AAT coinciding with the jump of the cold-to-warm phase of *** different time scale fluctuations in the past 51 years,the major cycle for both AAT0 and AAT10 in WS is 3.40 a,while the major cycles in ES are 3.64 a and 3.19 a,respectively with a sub-cycle of 7.29 *** fluctuation has an insignificant periodic characteristic of 25.50 a on the interdecadal scale(3)The spatial heterogeneity of AAT in WS is prominent and is mainly reflected by the significantly warm conditions in the south of the WS region and relatively slight warm conditions in the north,as well as by the isolated cooling area in the f

关键词： Sichuan Province Active accumulated temperature(AAT) Ensemble empirical mode decomposition(EEMD) Mutation analysis Empirical orthogonal function(EOF)

Intraregional Agricultural Characteristics Critical in Explaining Farmland Abandonment:Evidence from Chugoku and Shikoku Region of Japan

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Chinese Geographical Science 2020年第6期30卷 1111-1128页

作者： SU Guandong TOMOZAWA Kazuo OKAHASHI Hidenori CHEN Lin Department of geography Graduate School of LettersHiroshima UniversityHigashihiroshima 7398522Japan Department of geography Faculty of LettersNara UniversityNara 6318502Japan school of geography South China Normal UniversityGuangzhou 510631China

Since the 1980 s,Japan has witnessed an unprecedented decline in agriculture chiefly due to farmers’aging,depopulation,and unfavorable socio-economic *** development has resulted in an increase of farmland abandonment(FLA)across the ***,it remains unclear as to how and to what extent FLA is influenced by intraregional agricultural *** such,this article discusses the issue of FLA by taking a closer look at the Chugoku and Shikoku region,as it has experienced the highest FLA rates in Japan in recent *** this analysis,a total of 25 indicators retrieved from the census of agriculture and forestry at the former municipalities scale were selected to describe intraregional agricultural *** employed principal component analysis(PCA)to evaluate agricultural characteristics,while multiple linear regressions(MLR)was applied to explore their correlations with FLA and spatial ***,there are strong intraregional differences in the agricultural characteristics across the Chugoku and Shikoku region,with eight different principle components(PCs)describing their ***,variables measuring agricultural characteristics explain nearly 52.8%of the variation in FLA in our *** sales orientation and scale of agriculture have the strongest negative correlation to FLA in the region,while the status of agricultural succession displays the strongest positive correlation to ***,in areas where agriculture is more stable and easier to maintain,FLA is more strongly influenced by changes in agricultural characteristics than by geographical *** argue that localized approaches and policies for future management need to take intraregional differences in agricultural characteristics and FLA into *** findings help to explain spatial variations in agricultural characteristics and FLA in regional contexts,suggesting the need for better-informed farmland use policies to mitigate further aba

关键词： intraregional agricultural characteristics farmland abandonment(FLA) Chugoku and Shikoku region,Japan

A soil quality index for evaluation of degradation under land use and soil erosion categories in a small mountainous catchment, Iran

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Journal of Mountain Science 2019年第11期16卷 2577-2590页

作者： Kazem NOSRATI Adrian LCOLLINS Department of Physical geography School of Earth SciencesShahid Beheshti University*** TehranIran sustainable Agriculture Sciences Department Rothamsted ResearchNorth WykeOkehamptonEX202SBUK

Soil erosion and land use type have long been viewed as being particularly important drivers of soil *** objectives of this study,therefore,were to select a new soil quality index(SQI)which varies significantly with land use/soil erosion,and to evaluate the new SQI using expert *** total,18 soil physical,chemical,and biochemical properties(indicators)were measured on 56 soil samples collected from four land use/soil erosion categories(rangeland/surface erosion,rangeland/subsurface erosion,cultivated land/surface erosion and dry-farming land/surface erosion).Principal component and classification analysis(PCCA)identified five PCs that explained 77.7%of the variation in soil properties with the biochemical PC varying significantly with land use/soil *** discriminant analysis(GDA)selected urease and clay as the most sensitive properties distinguishing the land use/soil erosion *** GDA canonical scores for the new SQI were significantly correlated with expert opinion soil surface summed scores(for soil movement,surface litter,pedestalling,rills and flow pattern)derived using the *** of the Interior Bureau of Land Management(BLM)method.A forward stepwise general regression model revealed that the new SQI values were explained by soil movement,surface litter,and the summed values of the soil surface ***,this study confirmed that soil quality in the study area in Iran is controlled by land use and corresponding soil erosion.

关键词： Soil quality index Land use Erosion status Soil enzyme activities Multivariate statistical techniques

Deposition of Nutrients From Harmattan Dust in Ghana, West Africa

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Pedosphere 2015年第4期25卷 613-621页

作者： Henrik BREUNING-MADSEN Theodore Wola AWADZI Gry LYNGSIE Institute of Geosciences and Natural Resource Management University of Copenhagen Department of geography and Resource development University of Ghana

In order to measure dust's nutrient input on farmland in different agro-ecological zones, Harmattan dust was sampled by mats with plastic straw in Ghana between 2002–2006. The inputs of total nutrients by Harmattan dust in Ghana per Harmattan period were about 1–2 kg Ca ha-1, 0.5–2 kg K ha-1, 0.5–1.5 kg Mg ha-1and less than 0.5 kg P ha-1. Compared with the annual input of nutrients by precipitation, the dust accounted for 10% or less of Ca, Mg and K but approximately 20%–40% of P. The input of nutrients by dust was only valid for areas with vegetation, because in areas with none or sparse vegetation, loss of soil due to wind erosion and hereby loss of nutrients might be significant. In farmland areas with bare and vegetated fields there seemed to be an internal redistribution of the nutrients and not a net gain of nutrients from outside the area(long-range transported dust). The input of P by dust might be of some importance in the traditional shifting cultivation systems, while the inputs of other three nutrients of Ca, Mg and K were so low that they must be considered insignificant. In the intensive agriculture systems with huge inputs of manures and fertilizers the nutrient input by dust is insignificant and could be neglected.

关键词： deposition rate dust deposition input of nutrient long-range transported dust nutrient concentration traditionalagricultural system