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Does Biochar Addition Influence the Change Points of Soil Phosphorus Leaching?

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Journal of Integrative Agriculture 2014年第3期13卷 499-506页

作者： ZHAO Xiao-rong LI Dan KONG Juan LIN Qi-mei college of Resource and environmental sciences China Agricultural University

Phosphorus change point indicating the threshold related to P leaching, largely depends on soil properties. Increasing data have shown that biochar addition can improve soil retention capacity of ions. However, we have known little about weather biochar amendment influence the change point of P leaching. In this study, two soils added with 0, 5, 10, 20, and 50 g biochar kg-1 were incubated at 25℃ for 14 d following adjusting the soil moisture to 50% water-holding capacity （WHC）. The soils with different available P values were then obtained by adding a series of KH2PO4 solution （ranging from 0 to 600 mg P kg-1 soil）, and subjecting to three cycles of drying and rewetting. The results showed that biochar addition significantly lifted the P change points in the tested soils, together with changes in soil pH, organic C, Olen-P and CaC12-P but little on exchangeable Ca and Mg, oxalate-extractable Fe and Al. The Olsen-P at the change points ranged from 48.65 to 185.07 mg kg-1 in the alluvial soil and 71.25 to 98.65 mg kg^-1 in the red soil, corresponding to CaCl2-P of 0.31-6.49 and 0.18-0.45 mg L~, respectively. The change points of the alluvial soil were readily changed by adding biochar compared with that of the red soil. The enhancement of change points was likely to be explained as the improvement of phosphate retention ability in the biochar-added soils.

关键词： biochar soil phosphorus change point

Effect of NO_3^--N Enrichment on Seawater Stress Tolerance of Jerusalem Artichoke (Helianthus tuberosus)

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Pedosphere 2008年第1期18卷 113-123页

作者： S.K.MEHTA college of Resources and environmental sciences Nanjing Agricultural University

A hydroponic experiment with six treatments, i.e., 0% seawater （control）, 10% seawater, 25% seawater, 0% seawater ＋ N （7.5 mmol L-1 NaNO3）, 10% seawater ＋ N （7.5 mmol L-1 NaO3）, and 25% seawater ＋ N （7.5 mmol L-1 NaNO3）, was carried out to study the effect of nitrogen addition on the growth and physiological and biochemical characteristics of Jerusalem artichoke （Helianthus tuberosus） seedlings under seawater stress. The 10% seawater stress treatment had the least effect on plant growth while at 25% seawater growth was significantly inhibited. The malondialdehyde content and electrolyte leakage in leaves under 10% seawater were similar to those of the control, but significantly higher under the 25% seawater stress. The activities of superoxide dismutase, peroxidase and catalase in the leaves increased concomitantly with increasing seawater concentration and time. Proline and soluble-sugars in the leaves and Na^＋, K^＋, and Cl- contents in shoots and roots increased significantly with the concentration of seawater increasing. Nitrogen addition resulted in increasing fresh and dry weights of shoots and roots compared with seawater treatment without N. Nitrogen supplementation also significantly enhanced the activities of antioxidant enzymes in leaves. Addition of N to seawater enhanced the contents of proline and soluble-sugars in the leaves and K^＋ and total-N in the aerial parts and roots of H. tuberosus, but it resulted in declined concentrations of Na^＋ and Cl- in the aerial parts and roots. Nitrogen addition ameliorated the toxicity of seawater by improving the antioxidative enzymes, accumulating of proiine and soluble-sugars, and altering the distribution of inorganic ions in H. tuberosus.

关键词： Helianthus tuberosus ions distributions malondialdehyde nitrate seawater stress

Effect of Nitrogen Starvation on the Responses of Two Rice Cultivars to Nitrate Uptake and Utilization

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Pedosphere 2014年第5期24卷 690-698页

作者： YIN Xiao-Ming LUO Wei WANG Song-Wei SHEN Qi-Rong LONG Xiao-Hua college of Resources and environmental sciences Nanjing Agricultural University

Ammonium(NH+4) is the main nitrogen(N) form for rice crops, while NH+4near the root surface can be oxidized to nitrate(NO-3)by NH+4-oxidizing bacteria. Nitrate can be accumulated within rice tissues and reused when N supply is insufficient. We compared the remobilization of NO-3stored in the tissue and vacuolar between two rice(Oryza sativa L.) cultivars, Yangdao 6(YD6, indica)with a high N use efficiency(NUE) and Wuyujing 3(WYJ3, japonica) with a low NUE and measured the uptake of NO-3, expression of nitrate reductase(NR), NO-3transporter genes(NRTs), and NR activity after 4 d of N starvation following 7-d cultivation in a solution containing 2.86 mmol L-1NO-3. The results showed that both tissue NO-3concentration and vacuolar NO-3activity were higher in YD6 than WYJ3 under N starvation. YD6 showed a 2- to 3-fold higher expression of OsNRT2.1 in roots on the 1st and 4th day of N starvation and had significantly higher values of NO-3uptake(maximum uptake velocity, Vmax) than the cultivar ***, YD6 had significantly higher leaf and root maximum NR activity(NRAmax) and actual NR activity(NRAact) as well as stronger root expression of the two NR genes after the 1st day of N starvation. There were no significant differences in NRAmax and NRAact between the two rice cultivars on the 4th day of N starvation. The results suggested that YD6 had stronger NRA under N starvation, which might result in better NO-3re-utilization from the vacuole, and higher capacity for NO-3uptake and use, potentially explaining the higher NUE of YD6 compared with WYJ3.

关键词： nitrate reductase activity nitrate transpoters nitrogen use efficiency Oryza sativa L. remobilization

Combination of Ecoprofile and Least-cost Model for Eco-network Planning

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Chinese Geographical Science 2014年第1期24卷 113-125页

作者： XIAO He LIU Yunhui YU Zhenrong ZHANG Qian ZHANG Xin college of Resources and environmental sciences China Agricultural University

The protecting requirements and functional connectivity of species in isolated habitat patches are crucial factors of eco-network *** study aimed to improve the method of eco-network planning for species *** was used to group the species by similar behavior types,namely,choice of ecosystem,area requirement,and short distance dispersal abilities.A least-cost model was used to simulate the optimal corridor location to maintain functional connectivity.A combination of ecoprofile and least-cost model was hired to develop an eco-network that promoted species conservation.A case study was also conducted in Beijing,*** addition to the required ecosystem,habitat area is an important parameter for habitat *** area can remove noise habitat patches because of lacking ***-distance dispersal can be used to identify corridor requirements and avoid unnecessary building *** with various dispersal abilities exhibit significant differences in terms of corridor length and location *** isolation is the main threat for weakly mobile species,and habitat loss is the major risk of mobile species *** species groups also exhibit distinct landscape pattern demands for an eco-network,and the eco-network planning based on specific species can not protect other *** proposed that a combination of ecoprofile and least-cost model improved the efficiency of species conservation by eco-network planning.

关键词： eco-network ecoprofile least-cost model biodiversity conservation Beijing China

Average Amount and Stability of Available Agro-Climate Resources in the Main Maize Cropping Regions in China during 1981–2010

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Journal of Meteorological Research 2018年第1期32卷 146-156页

作者： Jin ZHAO Xiaoguang YANG college of Resources and environmental sciences China Agricultural University

The available agro-climate resources that can be absorbed and converted into dry matter could directly affect crop growth and yield under climate change. Knowledge of the average amount and stability of available agro-climate resources for maize in the main cropping regions of China under climate change is essential for farmers and advisors to optimize cropping choices and develop adaptation strategies under limited resources. In this study, the three main maize cropping regions in China—the North China spring maize region（NCS）, the Huanghuaihai summer maize region（HS）, and the Southwest China mountain maize region（SCM）—were selected as study regions. Based on observed solar radiation, temperature, and precipitation data, we analyzed the spatial distributions and temporal trends in the available agro-climate resources for maize during 1981-2010. During this period, significantly prolonged climatological growing seasons for maize [3.3, 2.0, and 4.7 day（10 yr）^-1 in NCS, HS, and SCM] were found in all three regions. However, the spatiotemporal patterns of the available agro-climate resources differed among the three regions. The available heating resources for maize increased significantly in the three regions, and the rates of increase were higher in NCS [95.5℃ day（10 yr）^-1] and SCM [93.5℃ day（10 yr）^-1] than that in HS [57.7℃ day（10 yr）^-1].Meanwhile, decreasing trends in the available water resources were found in NCS [–5.3 mm（10 yr）^-1] and SCM[–5.8 mm（10 yr）^-1], whereas an increasing trend was observed in HS [3.0 mm（10 yr）^-1]. Increasing trends in the available radiation resources were found in NCS [20.9 MJ m^-2（10 yr）^-1] and SCM [25.2 MJ m^-2（10 yr）^-1], whereas a decreasing trend was found in HS [11.6 MJ m^-2（10 yr）^-1]. Compared with 1981–90, the stability of all three resource types decreased during 1991–2000 and 2001–10 in the three regions. More consideration should be placed on the extreme events caused by more intense climate fluctuations. The results

关键词： maize available agro-climate resources stability variability

Effects of Earthworms and Ryegrass on the Removal of Fluoranthene from Soil

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Pedosphere 2013年第4期23卷 523-531页

作者： JING Yong-Ping LIU Man-Qiang YIN Qi-Peng LI Hui-Xin HU Feng college of Resources and environmental sciences Nanjing Agricultural University

Earthworms can promote the bioremediation of contaminated soils through enhancing plant growth and microorganism development. The individual and combined effects of earthworms and ryegrass （Lolium multifloram Lain.） on the removM of fiuoranthene from a sandy-loam alluvial soil were investigated in a 70-d microcosm experiment. The experiment was set up in a complete factorial design with treatments in four replicates： without earthworms or ryegrass （control, CK）, with earthworms only （E）, with ryegrass only （P）, and with both earthworms and ryegrass （EP）. The residual fluoranthene, microbial biomass C, and polyphenol oxidase activity in the soil changed significantly （P 〈 0.01） with time. In general, the residual concentration of fluoranthene in the soil decreased sharply from 71.8-88.7 to 31.7-37.4 mg kg-1 in 14 d, and then decreased gradually to 19.7-30.5 mg kg-1 on the 70th d. The flu- oranthene concentration left in the soil was the least with both earthworms and ryegrass, compared to the other treatments at the end of the experiment. Half-life times of fluoranthene in the E, P, and EP treatments were 17.8%-36.3% smaller than that of CK. More fluoranthene was absorbed by earthworms than ryegrass. However, the total amounts of fluoranthene accumulated in both the ryegrass and earthworms were small, only accounting for 0.01%-1.20% of the lost fluoranthene. Therefore, we assumed that microbial degradation would play a dominant functional role in fluoranthene removal from soil. We found that earthworms significantly increased microbial biomass C and polyphenol oxidase activity （P 〈 0.01） in the presence of ryegrass at the end of the experiment. Furthermore, microbial biomass C and polyphenol oxidase activity were significantly （P 〈 0.05） and negatively related to the residual fluoranthene concentration. This implied that earthworms might promote the removal of fluoranthene from soil via stimulating microbial biomass C and polyphenol oxidase activity.

关键词： microbial biomass C microbial degradation plant growth polyphenol oxidase activity residual concentration

Targeting cholesterol trafficking to mitigate axonal degeneration in hereditary spastic paraplegia

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Neural Regeneration Research 2025年第5期20卷 1397-1398页

作者： Zhenyu Chen Xue-Jun Li Department of Biomedical sciences University of Illinois College of Medicine RockfordRockfordILUSA Department of Bioengineering University of Illinois at ChicagoChicagoILUSA

Axonal degeneration underlies many debilitating diseases including hereditary spastic paraplegia(HSP),a genetically and clinically diverse group of disorders characterized by spasticity and weakness of the lower *** is one significant cause of chronic neurodisability due to the lack of effective treatments and a wide range of onset ages from early childhood to 70 years.

关键词： degeneration diseases hereditary

Adsorption and desorption of Cu2＋ on paddy soil aggregates pretreated with different levels of phosphate

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Journal of environmental sciences 2017年第5期29卷 311-320页

作者： Jun Dai Wenqin Wang Wenchen Wu Jianbo Gao Changxun Dong college of sciences Nanjing Agricultural University Nanjing 210095 China college of Resources and environmental sciences Nanjing Agricultural University Nanjing 210095 China South China Institute of environmental sciences Ministry of Environmental Protection Guangzhou 510655 China

Interactions between anions and cations are important for understanding the behaviors of chemical pollutants and their potential risks in the *** we prepared soil aggregates of a yellow paddy soil from the Taihu Lake region,and investigated the effects of phosphate（P） pretreatment on adsorption-desorption of Cu2＋ of soil aggregates,free iron oxyhydrates-removed soil aggregates,goethite,and kaolinite with batch adsorption *** results showed that Cu2＋ adsorption was reduced on the aggregates pretreated with low concentrations of P,and promoted with high concentrations of P,showing a V-shaped *** with the untreated aggregates,the adsorption capacity of Cu2＋ was reduced when P application rates were lower than 260,220,130 and110 mg/kg for coarse,clay,silt and fine sand fractions,*** the contrary,the adsorption capacity of Cu2＋ was higher on P-pretreated soil aggregates than on the control ones when P application rates were greater than those ***,the desorption of Cu2＋ was enhanced at low levels of P,but suppressed at high levels of P,displaying an inverted V-shaped change over P *** Cu2＋ adsorption by the aggregate particles with and without P pretreatments was well described by the Freundlich *** results were obtained on P-pretreated ***,such P effects on Cu2＋adsorption-desorption were not observed on kaolinite and free iron oxyhydrates-removed soil *** present results indicate that goethite is one of the main soil substances responsible for the P-induced promotion and inhibition of Cu2＋ adsorption.

关键词： Paddy soil Aggregates Copper (Ⅱ) Adsorption and desorption

Comprehensive Review and Analysis on Facial Emotion Recognition:Performance Insights into Deep and Traditional Learning with Current Updates and Challenges

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Computers, Materials & Continua 2025年第1期82卷 41-72页

作者： Amjad Rehman Muhammad Mujahid Alex Elyassih Bayan AlGhofaily Saeed Ali Omer Bahaj Artificial Intelligence&Data Analytics Lab College of Computer&Information SciencesPrince Sultan UniversityRiyadh11586Saudi Arabia MIS Department college of Business Administration Prince Sattam Bin Abdulaziz UniversityAlKharj11942Saudi Arabia

In computer vision and artificial intelligence,automatic facial expression-based emotion identification of humans has become a popular research and industry *** demonstrations and applications in several fields,including computer games,smart homes,expression analysis,gesture recognition,surveillance films,depression therapy,patientmonitoring,anxiety,and others,have brought attention to its significant academic and commercial *** study emphasizes research that has only employed facial images for face expression recognition(FER),because facial expressions are a basic way that people communicate meaning to each *** immense achievement of deep learning has resulted in a growing use of its much architecture to enhance *** review is on machine learning,deep learning,and hybrid methods’use of preprocessing,augmentation techniques,and feature extraction for temporal properties of successive frames of *** following section gives a brief summary of assessment criteria that are accessible to the public and then compares them with benchmark results the most trustworthy way to assess FER-related research topics *** this review,a brief synopsis of the subject matter may be beneficial for novices in the field of FER as well as seasoned scholars seeking fruitful avenues for further *** information conveys fundamental knowledge and provides a comprehensive understanding of the most recent state-of-the-art research.

关键词： Face emotion recognition deep learning hybrid learning CK+ facial images machine learning technological development