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Response of maize growth and soil biological characteristics to planting density under fertigation in a semi-arid region

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 186-192页

作者： Peng Jiang Lei Li Dejia Xu Rui Wang Quan Sun school of forestry and Prataculture Ningxia UniversityYinchuan 750021China Institute of Agricultural Resources and environment Ningxia Academy of Agriculture and Forestry SciencesYinchuan 750002China school of Agriculture Ningxia UniversityYinchuan 750021China

Increasing the planting density can exacerbate crop competition for water,nutrients and space which results in a decline in the crop ***,the effect of increasing planting density on crop growth and soil biological characteristics in barren sandy land in the semi-arid regions are still *** this study,we investigated the effects of six planting densities(5.4×10^(4),6.45×10^(4),7.95×10^(4),9.5×10^(4),9.75×10^(4) and 10.5×10^(4) plants/hm^(2))on maize growth,photosynthesis characteristics,yield and soil biological characteristics in barren sandy soil in the semi-arid region of Ningxia,*** results indicated that the stem diameter and spike length decreased linearly with increasing planting *** plant height,spike weight,grain weight and 100-grain weight decreased with increasing plating ***,the root length increased with increasing planting *** diameter,volume and activity increased and then decreased with increasing planting *** was no significant difference(p>0.05)in the effect of planting density on transpiration rate intercellular CO_(2) *** well,the soil microbial biomass carbon and microbial biomass nitrogen decreased with increasing planting *** soil catalase activities increased and then decreased with increasing planting *** alkaline phosphatase activity,the amounts of soil bacteria and actinomycetes increased with increasing planting ***,a moderately increasing planting density can improve maize yield when water and nutrients are *** optimal planting density was 8.29×10^(4) plants/hm^(2) and the highest yield was 15.84 t/hm^(2) in barren sandy soil in semi-arid region of Ningxia,*** study provides a theoretical basis for high yield and high efficiency of maize.

关键词： maize growth planting density yield fertigation soil enzyme activity

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The great catastrophe: causes of the Permo-Triassic marine mass extinction

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National Science Review 2024年第1期11卷 37-50页

作者： Paul B.Wignall David P.G.Bond school of Earth & environment University of Leeds school of environmental Sciences University of Hull

The marine losses during the Permo-Triassic mass extinction were the worst ever experienced. All groups were badly affected, especially amongst the benthos(e.g. brachiopods, corals, bryozoans, foraminifers,ostracods). Planktonic populations underwent a fundamental change with eukaryotic algae being replaced by nitrogen-fixing bacteria, green-sulphur bacteria, sulphate-reducing bacteria and prasinophytes. Detailed studies of boundary sections, especially those in South China, have resolved the crisis to a ～55 kyr interval straddling the Permo-Triassic boundary. Many of the losses occur at the beginning and end of this interval painting a picture of a two-phase extinction. Improved knowledge of the extinction has been supported by numerous geochemical studies that allow diverse proposed extinction mechanisms to be studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections globally, although the intensity and timing shows regional variability. Decreased ocean ventilation coincides with rapidly rising temperatures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting support from geochemical proxies and, even less likely, siltation(burial under a massive influx of terrigenous sediment) which lacks substantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the Permian was likely Siberian Trap eruptions and their associated carbon dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter episodes stemming from Siberian volcanism have also been linked to the crisis, but the short-term nature of these episodes(

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic winter

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Degradation behaviors of Nabumetone and its metabolite during UV/monochloramine process:Experimental and theoretical study

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Journal of environmental Sciences 2024年第8期142卷 103-114页

作者： Xiang Tu Yunsong Bai Qing Fu Sheng Chang Kunfeng Zhang Yang Pan Ruiyang Xiao Yifu Fu Qi Zhang State Key Laboratory of environmental Criteria and Risk Assessment State Environmental Protection Key Laboratory of Drinking Water Source ProtectionResearch Centre of Lake EnvironmentNational Engineering Laboratory for Lake Pollution Control and Ecological RestorationChinese Research Academy of Environmental SciencesBeijing 100012China school of environmental Science and Engineering Suzhou University of Science and TechnologySuzhou 215009China Institute of environmental Engineering School of Metallurgy and EnvironmentCentral South UniversityChangsha 410083China school of forestry Northeast Forestry UniversityHarbin 150040China

This study investigated degradation behaviors of a nonsteroidal anti-inflammatory drug Nabumetone(NMT)and its major metabolite 6-methoxy-2-naphthylacetic acid(MNA)in the coupling process of ultraviolet and monochloramine(UV/NH2Cl).The second-order rate constants of the contaminants reacting with reactive radicals(HO·,Cl·,Cl_(2)·-,and CO_(3)·^(-))were determined by laser flash photolysis ***·and Cl·contributed predominantly with 52.3%and 21.7%for NMT degradation and 60.8%and 22.3%for MNA *** presence of chlorides retarded the degradation of NMT,while promoted the destruction of MNA,which was ascribed to the photosensitization effects of MNA under UV *** functional theory(DFT)calculations revealed that radical adduct formation(RAF)was dominant pathway for both HO·and Cl·reacting with the contaminants,and hydrogen atom transfer(HAT)preferred to occur on side chains of NMT and *** reacted with NO_(2)·through single electron transfer(SET)with the second-order rate constant calculated to be 5.35×10^(7)(mol/L)^(-1)sec^(-1),and the contribution of NO_(2)·was predicted to be 13.0%of the total rate constant of NMT in pure water,which indicated that NO_(2)·played a nonnegligible role in the degradation of *** acute toxicity and developmental toxicity of NMT were enhanced after UV/NH_(2)Cl treatment,while those of MNA were *** transformation products of both NMT and MNA exhibited higher mutagenicity than their parent *** study provides a deep understanding of the mechanism of radical degradation of NMT and MNA in the treatment of UV/NH2Cl.

关键词： UV/NH_(2)Cl Reactive species Degradation kinetics Reaction mechanism Degradation products

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Spatial pattern recognition for near-surface high temperature increases in mountain areas using MODIS and SRTM DEM

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Journal of Mountain Science 2024年第6期21卷 2025-2042页

作者： WANG Yanxia YANG Lisha HUANG Xiaoyuan ZHOU Ruliang school of Soil and Water Conservation Southwest Forestry UniversityKunming 650224China school of Economics and Management Southwest Forestry UniversityKunming 650224China

Abrupt near-surface temperature changes in mountainous areas are a special component of the mountain climate *** and accurate measurements of the locations,intensity,and width of the near-surface changes are necessary but highly difficult due to the complicated environmental conditions and instrumental *** paper develops a spatial pattern recognition method to measure the near-surface high temperature increase(NSHTI),one of the lesser-attended ***,raster window measurement was proposed to calculate the temperature lapse rate using MODIS land surface temperature and SRTM DEM *** fully considers the terrain heights of two neighboring cells on opposite or adjacent slopes with a moving window of 3×3 cell ***,a threshold selection was performed to identify the NSHTI cells using a threshold of-0.65℃/100 ***,the NSHTI strips were parameterized through raster vectorization and spatial *** Yunnan,a mountainous province in southwestern China,as the study area,the results indicate that the NSHTI cells concentrate in a strip-like pattern along the mountains and valleys,and the strips are almost parallel to the altitude contours with a slight northward ***,they are located mostly at a 3/5 height of high mountains or within 400 m from the valley floors,where the controlling topographic index is the altitude of the terrain trend surface but not the absolute elevation and the topographic uplift height and cutting ***,the NSHTI intensity varies with the geographic locations and the proportions increase with an exponential trend,and the horizontal width has a mean of about 1000 m and a maximum of over 5000 *** result demonstrates that the proposed method can effectively recognize NSHTI boundaries over mountains,providing support for the modeling of weather and climate systems and the development of mountain resources.

关键词： High temperature increase Mountain areas MODIS Spatial pattern recognition Raster window measurement Threshold selection

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Reproductive patterns in Araucaria araucana forests in the Andean range, Chile

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Ecological Processes 2024年第01期13卷 252-261页

作者： Sergio Donoso Karen Pe?a-Rojas Claudia Espinoza Carolain Badaracco Rómulo Santelices-Moya Antonio Cabrera-Ariza Mediterranean Forests Laboratory Faculty of Forestry and Nature Conservation Centro Secano Faculty of Agricultural and Forestry Sciences Universidad Católica del Maule Maule Advanced studies Research Center Vice-Rector's Office for Research and Postgraduate Studies Catholic University of Maule

Background Araucaria araucana is a mast species that presents a high variability in annual cone production. Researchers have recorded synchronization events in cone production in different populations, which allows the seed production to be concentrated, reducing the percentage of seeds consumed by different animal *** We sampled three populations located in the Andes Mountains, Araucanía Region, Chile. In 2004 we began the collection of data on cone production, for which we installed permanent plots（1200 m2each） at each location. We identified and labeled each female tree in each plot to monitor its cone production. In 2012 we selected a total of 30 trees near the plots to evaluate the number of seeds per cone. In each February from 2012 to 2014 we selected two mature cones and covered them with a porous mesh for subsequent collection and storage in March. At the beginning of June, we counted and weighed the seeds, determining the average weight, the number of seeds per cone, the germination capacity（GC）, and the germination speed（GS）.Results Cone production was synchronous across the three locations. We observed significant differences among the locations and years evaluated. The cones had fewer seeds in 2013（high production） compared to those in 2012（low production）, but their weights were similar. In 2014 the cones produced smaller seeds in fewer quantities. The difference between the years 2013 and 2014 resulted from the high-energy expenditure in 2013. Regarding GC and GS, there were significant differences among the three locations（GC: F = 45.41, p < 0.01; GS: F = 96.08, p < 0.01）, where the highest values were observed in *** Both GC and GS are related to seed weight but not to the number of cones produced in a given year. These annual fluctuations in seed production are determining factors in the population dynamics of forest species. Our results allow a better understanding of the reproductive phenology of A. araucana and could hel

关键词： Seed weight Germination potential Masting species Sustainable use Dioecious species

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Effects of organic fertilizers on organic carbon accumulation in alkalized saline soil and silage maize yield

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 159-168页

作者： Lidong Ji Lei Li Rui Wang Xing Xu Fengju Zhang Guilian Mao Teng Wang school of forestry and Prataculture Ningxia UniversityYinchuan750021China school of Agriculture Ningxia UniversityYinchuan750021China school of Ecological environment Ningxia UniversityYinchuan 750021China school of Life Sciences Ningxia UniversityYinchuan 750021China

To understand the combined effect of organic and chemical fertilizers on soil carbon emissions and carbon balance of a farmland ecosystem,this study investigated the organic fertilizer nitrogen replacing different proportions of chemical fertilizer *** results showed that,compared to F_(100),the O_(15)F_(85) treatment increased the yield and net ecosystem productivity carbon sequestration of silage maize under mild,moderate,and severe salinization levels,as well as the contents of soil organic carbon,microbial carbon,and humin carbon,while reducing plant carbon *** O_(15)F_(85) treatment did not significantly increase soil carbon emissions(CEC),but O_(30)F_(70),O_(45)F_(55) and O_(100) treatments significantly increased *** soil carbon balance analysis showed that the farmland ecosystem was a“sink”for atmospheric CO_(2) under each *** O_(15)F_(85) treatment produced an“excitation effect”to enhance the carbon sink effect of silage maize farmland under mild,moderate and severe salinization levels while maintaining stable production and *** the O_(100) treatment increased the carbon sink of farmland under different salinization levels,the yield was significantly reduced and did not represent practical production *** analysis showed that soil organic carbon components and ecosystem carbon balance were closely related to soil total salt,pH and bulk density,while soil dissolved organic carbon,humus carbon components and carbon emissions were closely related to soil moisture and ***,the purpose of improving the carbon sink of saline-alkali land can be achieved through soil salt inhibition,soil structure remodeling and water supplement and warming regulation,which provides technical and theoretical support for reducing carbon emissions,achieving carbon neutrality and alleviating global warming.

关键词： carbon balance carbon component organic carbon organic substitution saline-alkali land

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Sustainable Seawater Desalination and Energy Management:Mechanisms,Strategies,and the Way Forward

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Research 2024年第3期2023卷 595-611页

作者： Meng Wang Yen Wei Ruoxin Li Xin Wang Chengyu Wang Nanqi Ren Shih-Hsin Ho State Key Laboratory of Urban Water Resource and environment School of EnvironmentHarbin Institute of TechnologyHarbin 150001China Department of Chemistry Tsinghua UniversityBeijing 100084China Key Laboratory of Bio-based Material Science&Technology(Northeast forestry University) Ministry of EducationHarbin 150040China.

Solar-driven desalination systems have been recognized as an effective technology to address the water ***,evaporators prepared based on advanced manufacturing technologies have emerged as a promising tool in enhancing ocean energy *** this review,we discussed the thermal conversion,energy flow,salt deposition mechanisms,and design strategies for solar-driven desalination systems,and explored how to improve the desalination performance and energy use efficiency of the systems through advanced manufacturing *** future perspectives,we determined the feasibility of coupling solar-driven solar desalination systems with multi-stage energy utilization systems and emerging artificial intelligence technologies,for which conclusions are given and new directions for future desalination system development are ***,exciting opportunities and challenges in the face of basic research and practical implementation are discussed,providing promising solutions and blueprints for green and novel desalination technologies while achieving sustainable development.

关键词： Sustainable Solar directions

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Design of multi-section luffing apple pruning equipment and cutting test of the key components

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 109-117页

作者： Siyuan Tong Wenbin Li Yaxiong Wang Lei Zhang Feng Kang school of Technology Beijing Forestry UniversityKey Lab of State Forestry and Grassland Administration for Forestry Equipment and AutomationBeijing 100083China

In order to reduce the labor intensity and improve the efficiency of pruning,this study designed a multi-section luffing apple pruning equipment suitable for apple orchards in hilly and mountainous areas of *** the essay,the structure and working principle of the equipment are expounded,the cutter was analyzed,and the parameters were *** the self-made test bench to simulate the field experiment,this study selected the ratio of cutting speed to feeding speed and feeding speed as the influencing factors and took the cut-off rate,cutting efficiency and cutting power as the objectives to carry out single factor experiment and quadratic regression orthogonal *** test results show that the cutting power increases with the increase of ratio of cutting speed to feeding speed,and the cut-off rate and cutting efficiency first increase and then *** the feeding speed increases,the cutting efficiency and power increase,and the cut-off rate *** the cutoff rate was greater than 80%,the optimal combination of operating parameters was the feeding speed of 0.55 m/s and ratio of cutting speed to feeding speed of *** this combination,the cut-off rate was 84.9%,the cutting efficiency was 13.1,and the cutting power was 175.7 *** error between the predicted target value of the model and the average measured target value was less than 7%,so the test results are *** to the obtained optimal operating parameters,the actual cutting experiment of the pruning equipment in the field was carried out,and the cutting rate was 96.3%,which meet the design *** study can also meet the needs of mechanized pruning of fruit trees with different crown shapes,improve the applicability of pruning equipment,and provide support for the development of mechanized pruning equipment in China.

关键词： apple pruning equipment cutting test optimal parameters regression analysis

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Comparison of antimony and arsenic behaviour at the river-lake junction in the middle of the Yangtze River Basin

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Journal of environmental Sciences 2024年第2期136卷 189-200页

作者： Huiji Liu Wei Zeng Ziyang Lai Mengchang He Chunye Lin Wei Ouyang Xitao Liu State Key Laboratory of Water environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China Advanced Interdisciplinary Institute of environment and Ecology Beijing Normal UniversityZhuhai 519087China

As typical metalloid toxic elements widely distributed in environmental media,the geochemical behaviour of antimony(Sb)and arsenic(As)affects environmental *** selected the surface waters and sediments at the river-lake junction of Dongting Lake as the research objects,analysed the concentration and chemical partitioning of Sb and As,assessed its contamination and ecological risk levels,and discussed its sources and potential influencing *** concentrations of dissolved Sb and As in surface waters were low(studies on the environmental behaviour of metalloids in specific hydrological conditions,such as river-lake junctions.

关键词： Contamination Ecological risks Antimony(Sb) Arsenic(As) River-lake junction Dongting Lake

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Can urban forests provide acoustic refuges for birds?Investigating the influence of vegetation structure and anthropogenic noise on bird sound diversity

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Journal of forestry Research 2024年第2期35卷 163-175页

作者： Zezhou Hao Chengyun Zhang Le Li Bing Sun Shuixing Luo Juyang Liao Qingfei Wang Ruichen Wu Xinhui Xu Christopher A.Lepczyk Nancai Pei Research Institute of Tropical forestry Chinese Academy of ForestryGuangzhou 510520People’s Republic of China school of Electronics and Communication Engineering Guangzhou UniversityGuangzhou 510006People’s Republic of China Hunan Botanical Barden Changsha 410116People’s Republic of China Guangdong Eco-Engineering Polytechnic Guangzhou 510520People’s Republic of China College of forestry Wildlife and EnvironmentAuburn UniversityAuburnAL 36849USA

As a crucial component of terrestrial ecosystems,urban forests play a pivotal role in protecting urban biodiversity by providing suitable habitats for acoustic *** studies note that vegetation structure is a key factor influencing bird sounds in urban forests;hence,adjusting the frequency composition may be a strategy for birds to avoid anthropogenic noise to mask their ***,it is unknown whether the response mechanisms of bird vocalizations to vegetation structure remain consistent despite being impacted by anthropogenic *** was hypothesized that anthropogenic noise in urban forests occupies the low-frequency space of bird songs,leading to a possible reshaping of the acoustic niches of forests,and the vegetation structure of urban forests is the critical factor that shapes the acoustic space for bird *** acoustic monitoring in various urban forests was used to monitor natural and anthropogenic noises,and sounds were classified into three acoustic scenes(bird sounds,human sounds,and bird-human sounds)to determine interconnections between bird sounds,anthropogenic noise,and vegetation *** noise altered the acoustic niche of urban forests by intruding into the low-frequency space used by birds,and vegetation structures related to volume(trunk volume and branch volume)and density(number of branches and leaf area index)significantly impact the diversity of bird *** findings indicate that the response to low and high frequency signals to vegetation structure is *** clarifying this relationship,our results contribute to understanding of how vegetation structure influences bird sounds in urban forests impacted by anthropogenic noise.

关键词： Anthropogenic noise Bird sounds Urban forests Vegetation structure

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