期刊文献+
共找到4篇文章
< 1 >
每页显示 20 50 100
农田土壤中氮的环境指标研究 被引量:13
1
作者 田艳 马友华 +5 位作者 胡宏祥 吴蔚君 徐云连 赵学敏 龚娟 awais shakoor 《中国农学通报》 2017年第7期142-147,共6页
氮肥的大量不合理施用使农田氮素成了农业面源污染的重要因子,然而关于农田氮素对环境污染的标准并没有系统的介绍。笔者分别从农田土壤氮素盈余、农田径流总氮、铵态氮、硝态氮等方面着手,介绍农田土壤中氮对环境产生的影响。土壤中氮... 氮肥的大量不合理施用使农田氮素成了农业面源污染的重要因子,然而关于农田氮素对环境污染的标准并没有系统的介绍。笔者分别从农田土壤氮素盈余、农田径流总氮、铵态氮、硝态氮等方面着手,介绍农田土壤中氮对环境产生的影响。土壤中氮素富集会加大农田土壤氮流失至水体的风险和数量。农田生态系统中氮素通过氨挥发、地表径流、下渗淋失等进入到环境,其盈余主要以气态、可溶态等形态对环境造成污染。综述国内外相关研究得到:农田径流损失的氮以可溶态为主,其中水稻田面水氮浓度超过30 mg/L会促使土壤矿质态氮部分释放,增加土壤溶液中矿质态氮含量,增加农田土壤氮流失风险;土壤无机N含量达到60 mg/kg时能满足作物的正常生长,超过此值,N素流失风险增加,多余的土壤NO3-N将会引起较大的环境风险。化肥使用量控制在150~180 kg/(hm^2·a)之内,可以有效控制化肥氮的损失污染。土壤氮素盈余、农田径流总氮、铵态氮、硝态氮等可作为农田土壤中氮的环境指标。 展开更多
关键词 农田 土壤氮 环境指标 氮素盈余 总氮 铵态氮 硝态氮
下载PDF
Divergent consequences of bio-resources on morphological plasticity and biochemical responses in early-stage leguminous species:Sustainable productivity approaches 被引量:2
2
作者 Taimoor Hassan Farooq Muhammad Farrakh Nawaz +5 位作者 Muhammad Qasid awais shakoor Irfan Ahmad Sadaf Gul Khuram Shahzad Xiaoyong Chen 《Geoscience Frontiers》 SCIE CAS CSCD 2024年第3期312-321,共10页
Inorganic resources can be detrimental to the environment when exploited.In comparison,organic resources help balance the soil’s carbon and nitrogen(C/N)ratio,enhance soil fertility and benefit ecological protection.... Inorganic resources can be detrimental to the environment when exploited.In comparison,organic resources help balance the soil’s carbon and nitrogen(C/N)ratio,enhance soil fertility and benefit ecological protection.Current climate crises,rapid urbanization,and fast population growth are causing many natural forests to be converted to agricultural and industrial lands to fulfill ever-increasing food and developmental requirements.Application of different bio-resources becomes necessary for sustainable productivity of available lands.This study explores the effects of various organic amendments on the growth,morpho-physiological and biochemical attributes of three leguminous tree species:Dalbergia sissoo,Vachellia nilotica,and Acacia ampliceps,concerning sustainable productivity.One-year-old healthy,disease-free,and homogenous seedlings were used as study material in a greenhouse pot experiment.Four organic amendments,i.e.,compost(CMP),cow dung(CD),poultry manure(PM),and biochar(BC),along with a control(CK)treatment,were applied.Results showed that all the organic amendments performed significantly better(P<0.05)than CK.CD produced the most significant results,followed by BC application,while PM influence was the least.Among all treatments and species,the maximum values of root length,root biomass,chlorophyll content,carotenoids,catalase,and total phenolic content were recorded under the CD treatment.Whereas for plant height and collar diameter,no big differences were observed between CD and BC(P=0.054).While comparing species,V.nilotica growth was significantly enhanced under organic amendments,followed by A.ampliceps.Combined and comparative results of studied parameters conclude that CD and BC were the most effective organic amendments,which greatly improved the growth of experimental leguminous tree species;this makes these two biofertilizers a powerful tool for sustainable agricultural productivity.Our study contributes toward an enhanced understanding of plant’s morpho-physiological responses,biochemical growth patterns,controls,and activities under different bio-fertilizers. 展开更多
关键词 Bio-fertilizers Crop productivity Ecological sustainability Nitrogen fixation Organic cultivation Physiological responses
原文传递
Morpho-anatomical adaptations of dominantly grown wild Datura inoxia to wastewater resource:Productivity and ecological issues 被引量:1
3
作者 Taimoor Hassan Farooq Shagufta Jabeen +5 位作者 awais shakoor Muhammad Saleem Arif Nadia Siddique Khuram Shahzad Muhammad Umair Riaz Yong Li 《Geoscience Frontiers》 SCIE CAS CSCD 2024年第3期248-258,共11页
With the increasing global water scarcity,wastewater irrigation has become widespread,but it can have detrimental ecological consequences.Although wastewater contains valuable nutrients for plants,improper treatment o... With the increasing global water scarcity,wastewater irrigation has become widespread,but it can have detrimental ecological consequences.Although wastewater contains valuable nutrients for plants,improper treatment or the use of untreated wastewater in irrigation can negatively impact soil fertility and plant growth.This study is divided into two parts:firstly,a phytosociological survey was conducted to identify plant species with the highest importance value index(IVI)in the vicinity of wastewaterirrigated areas.Secondly,a comparative morpho-anatomical analysis was carried out to investigate the morpho-anatomical adaptations of the species with the highest IVI under wastewater irrigation compared to normal water irrigation.The results of the phytosociological survey revealed the presence of 51 plant species in the vicinity of the wastewater-irrigated areas,with varying relative densities and coverage.Datura inoxia exhibited the highest IVI(28.79),followed by Xanthium strumarium(24.34),while Lippia nodiflora showed the lowest IVI(1.86).The morphological growth of D.inoxia was superior under normal water irrigation,but the average root length was greater under wastewater irrigation.Regarding cell anatomy,cell thickness and cell area characteristics in the dermal,ground,and vascular tissues of the stem and root tended to be greater under wastewater treatment.However,the opposite trend was observed in leaf anatomical analysis,possibly due to the combined effect of wastewater and climatic conditions.Stem and root xylem thickness were greater under wastewater irrigation,whereas phloem thickness was higher under normal water irrigation.The number of vascular bundles in the stem,root,and leaf was higher under wastewater treatment compared to normal water irrigation,but their arrangement was circular in the latter and scattered under wastewater irrigation.Datura inoxia demonstrated strong adaptive potential under wastewater irrigation,as indicated by its highest relative density,coverage,and IVI,suggesting its suitability for phytoremediation.However,due to the low relative density,coverage,and IVI of many other species,the use of untreated wastewater for irrigation cannot be appreciated. 展开更多
关键词 Water pollution PHYTOSOCIOLOGY Structural growth PHYTOREMEDIATION Agricultural irrigation Ecological concerns
原文传递
Soil mineral nitrogen dynamics in fallow periods in a rainfed semiarid Mediterranean agricultural system 被引量:1
4
作者 awais shakoor Àngela D.BOSCH-SERRA +2 位作者 Antonio LIDON Damián GINESTAR Jaime BOIXADERA 《Pedosphere》 SCIE CAS CSCD 2023年第4期622-637,共16页
Rainfed agricultural systems in semiarid Mediterranean environments are subject to erratic but often heavy rainfall events.As an agronomic practice,fallow periods can be included even within the existing European Unio... Rainfed agricultural systems in semiarid Mediterranean environments are subject to erratic but often heavy rainfall events.As an agronomic practice,fallow periods can be included even within the existing European Union common policy for crop diversification.This study aimed to quantify the effects of previous mineral fertilization on soil mineral nitrogen(N_(min))content and potential nitrate leaching during no-till fallow periods of crop rotation.The Leaching Estimation and Chemistry Model(LEACHM)was used for soil N_(min)prediction after fallow.During fallow periods,N_(min)measured in the soil profile increased by an average of 125 kg N ha^(-1),whereas the model showed an average increase of 95 kg N ha^(-1).The amount of nitrogen(N)leached was estimated to be 11–38 kg N ha^(-1).The N balance simulated using LEACHM might differ from the actual situation.The calibrated LEACHM underestimated soil N_(min)after a drought period followed by soil water replenishment,probably due to a pulse in soil C and N mineralization caused by the wetting of dry soil,but overestimated soil N_(min)after occasional rainy spells when soil quickly became saturated,probably due to occasional nitrous oxide emissions not being fully accounted for by the model and specific preferential water flow,which might lead to greater nitrate leaching than that simulated by LEACHM using the convection-dispersion equation.The results show that soil N_(min)measurements after fallow periods cannot be well predicted by LEACHM.The findings of this study provide a support for fertilization planning for crop rotation systems including a fallow period to avoid overfertilization in the following cropping season and reduce N environmental impacts. 展开更多
关键词 crop rotation Latin Hypercube-One factor at a Time(LH-OAT)method Leaching Estimation and Chemistry Model(LEACHM) mineral fertilizer nitrogen balance nitrogen environmental impacts nitrogen leaching soil water
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部