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文章速递Contribution of Good Agricultural Practices to Soil Biodiversity 认领
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作者 Beata Houšková Rastislav Bušo Jarmila Makovníková 《生态学期刊(英文)》 2021年第1期75-85,共11页
At present time when climate change has negative effect on soil moisture and can decrease significantly the productivity, good agricultural practises have a high importance via their direct influence on soil propertie... At present time when climate change has negative effect on soil moisture and can decrease significantly the productivity, good agricultural practises have a high importance via their direct influence on soil properties, regimes and biodiversity. Objectives of this study have been focused on the assessment of good agricultural practises in different soil cultivation types: conventional, minimum till, mulch, no-till and organic farming. Method used was based on two case study areas where organic and/or minimal farming systems have been applied. As a control, we chose soil with traditional cultivation. In organic farm, we evaluated earthworms;their amount and status and in farm with different types of cultivation we evaluated the microbial activity to assess the biodiversity conditions. Basic soil properties and soil structure have been set to be able to assess the influence of good agricultural practises on soil environment. Our study shows positive effect of these practises on soil moisture content, biodiversity and soil structure stability. These findings can be used for further studies determining the ways of soil cultivation in harmony with nature—in sustainable way. 展开更多
关键词 Good Agricultural Practices Soil Biodiversity Earthworms Microorganisms Soil Enzymes Organic Farm Soil Moisture
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Changes in soil organic carbon and aggregate stability following a chronosequence of Liriodendron chinense plantations 认领
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作者 Qicong Wu Xianghe Jiang +2 位作者 Qianwen Lu Jinbiao Li Jinlin Chen 《林业研究:英文版》 SCIE CAS 2021年第1期355-362,共8页
The objectives for this study were to determine changes in soil organic carbon(SOC)components and water-stable aggregates for soil profi les from diff erent ages of plantations of Liriodendron chinense and to clarify ... The objectives for this study were to determine changes in soil organic carbon(SOC)components and water-stable aggregates for soil profi les from diff erent ages of plantations of Liriodendron chinense and to clarify which organic carbon component is more closely associated with the formation and stability of soil aggregates.Three layers of soil(depths 0–20 cm,20–40 cm,40–60 cm)were collected from young,half-mature and mature stages of L.chinense.SOC,readily oxidizable organic carbon,chemically stable organic carbon and aggregate composition were determined.Intermediate stable organic carbon,the microbial quotient and aggregate stability(mean weight diameter)were calculated.SOC and aggregate stability in the L.chinense plantation did not increase linearly with an increase in L.chinense age;rather,they fi rst decreased,then increased with increasing age of L.chinense.The microbial quotient had a negative eff ect on the level of organic carbon and the stability of aggregates,while chemically stable organic carbon had a positive eff ect,which explained 55.0%and 19.3%of the total variation,respectively(P<0.01).Therefore,more attention should be paid of these two indicators in the future. 展开更多
关键词 Soil organic carbon Aggregate stability Liriodendron chinense plantation CHRONOSEQUENCE Soil depth
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Effect of natural and anthropogenic acidifi cation on aluminium distribution in forest soils of two regions in the Czech Republic 认领
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作者 Lenka Pavlů LubošBorůvka +1 位作者 Ondřej Drábek Antonín Nikodem 《林业研究:英文版》 SCIE CAS 2021年第1期363-370,共8页
To elucidate the dynamics of aluminium(Al),an element potentially toxic and strongly aff ected by acidifi cation processes,in soils,we selected two regions that were similar in relief,soil types,and vegetation cover b... To elucidate the dynamics of aluminium(Al),an element potentially toxic and strongly aff ected by acidifi cation processes,in soils,we selected two regions that were similar in relief,soil types,and vegetation cover but diff ered markedly in their history of acid precipitation:the JizerskéMountains(anthropogenically acidifi ed)and the NovohradskéMountains(naturally acidifi ed)in the Czech Republic.The levels of Al forms(exchangeable and organically bound)associated with diff erent environmental impacts were measured and univalent,divalent and trivalent Al species were quantifi ed using HPLC/IC.Exchangeable and organically bound Al concentrations were higher in the anthropogenically acidifi ed area.Only the concentrations of the leastdangerous species,the univalent,in organic soil horizons were similar for both mountains.The concentrations of exchangeable Al forms were correlated with Ca concentrations and with pH in the organic horizon.The known relationship of Al with soil pH was stronger in the mineral horizons.Relationships of exchangeable Al forms concentrations with sulphur concentrations or even more with the sulphur calcium molar ratio were found only in the JizerskéMountains,not in the Novohradské.Generally,the obtained results support the hypothesis that mechanisms diff ered between natural and anthropogenic acidifi cation. 展开更多
关键词 Soil acidifi cation Spruce forest Soil properties Aluminium forms Aluminium species
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文章速递旱作烤烟膜秸组合覆盖对土壤性质和烟叶产质量的影响 认领
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作者 邱岭军 张翔 +6 位作者 毛家伟 李亮 李琦 司贤宗 索炎炎 程培军 孔德辉 《山西农业科学》 2021年第2期189-194,256,共7页
设置地膜覆盖(T1)、小麦秸秆覆盖(T2)、地膜+小麦秸秆覆盖(T3)和地膜+小麦秸秆粉碎覆盖(T4)共4个处理进行田间对比试验,探究地膜与秸秆覆盖组合模式对旱作烤烟土壤肥力特性、农艺性状、光合特性、微生物区系、水热状况及烤后烟产质量的... 设置地膜覆盖(T1)、小麦秸秆覆盖(T2)、地膜+小麦秸秆覆盖(T3)和地膜+小麦秸秆粉碎覆盖(T4)共4个处理进行田间对比试验,探究地膜与秸秆覆盖组合模式对旱作烤烟土壤肥力特性、农艺性状、光合特性、微生物区系、水热状况及烤后烟产质量的影响。结果表明,在移栽后35 d,秸秆覆盖的T2处理土壤含水率、土壤温度显著低于其他处理,可能是春季冷热频繁,只秸秆覆盖对烟株前期生长的促进作用较弱,而在移栽后70 d,有秸秆覆盖的T2、T3和T4处理的土壤含水率显著高于T1处理,不同处理间的土壤温度差异不显著;T4处理的土壤细菌、真菌、放线菌数量较T1处理分别提高了26.09%、56.25%、84.44%,且与T1、T2和T3处理的细菌、真菌、放线菌数量间均存在显著性差异;不同膜秸覆盖组合措施的覆盖效果也存在差异,通过改变土壤生境进而影响微生物数量,地膜+小麦秸秆粉碎覆盖的T4处理烟叶品质最佳且经济性状好,较T1处理产量提升11.65%,产值增加19.06%,中上等烟比例均提升21.94%。垄体地膜覆盖+垄沟小麦秸秆粉碎覆盖处理是豫西地区烤烟种植过程中较优的耦合模式,能有效改善烟田土壤生物学特性,提升烟叶品质。 展开更多
关键词 烤烟 土壤 地膜 秸秆覆盖 土壤性质 产量
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文章速递Metal Accumulation Capability by <i>Platanus acerifolia</i>(Aiton) Willd., <i>Ailantus altissima</i>(Mill.) Swingle, <i>Robinia pseudoacacia</i>L. and <i>Quercus ilex</i>L., Largely Distributed in the City of Rome 认领
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作者 Loretta Gratani Olena Vasheka Francesco Bigaran 《美国植物学期刊(英文)》 2021年第1期163-185,共23页
The main of the research was to analyze the leaf metal accumulation capability of </span><i><span style="font-family:Verdana;">Platanus acerifolia</span></i><span style="... The main of the research was to analyze the leaf metal accumulation capability of </span><i><span style="font-family:Verdana;">Platanus acerifolia</span></i><span style="font-family:Verdana;"> (Aiton) Willd., </span><i><span style="font-family:Verdana;">Ailantus altissima</span></i><span style="font-family:Verdana;"> (Mill.) Swingle, </span><i><span style="font-family:Verdana;">Robinia pseudoacacia </span></i><span style="font-family:Verdana;">L. and</span><i><span style="font-family:Verdana;"> Quercus ilex</span></i><span style="font-family:Verdana;"> L., largely distributed in Rome. In addition, metal concentration was analyzed in the soil, sampling sites were chosen in historical parks (A sites) and high traffic level sites (B sites). The results highlight significant higher leaf and soil metal concentrations in B than in A sites. The ratio between metal concentration in leaves and soils (Biological Absorption Coefficient, BAC) for all the considered sites was significantly different among the species.</span><i> </i><span style="font-family:Verdana;">Morphological and anatomical leaf traits of the considered species show significant differences in A and B sites in response to traffic level. Overall, the results highlight the importance of the selection of tree species in urban areas for their ability to lower pollution levels. 展开更多
关键词 Metals Leaf Soil Urban Areas Traffic Density Portable X-Ray Fluorescence
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文章速递Zai Pit Effects on Selected Soil Properties and Cowpea (<i>Vigna unguiculata</i>) Growth and Grain Yield in Two Selected Dryland Regions of Kenya 认领
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作者 Sillus O. Oduor Nancy W. Mungai Seth F. O. Owido 《土壤科学期刊(英文)》 2021年第1期39-57,共19页
Erratic rainfall and temperature regimes, strongly affect agricultural productivity. To address the reduction in production, this study assessed the effect of Zai pit depths on selected soil properties and cowpea grow... Erratic rainfall and temperature regimes, strongly affect agricultural productivity. To address the reduction in production, this study assessed the effect of Zai pit depths on selected soil properties and cowpea growth and grain yield. “Zai” pit technology was tested in two locations falling under Agroecological Zone IV (relatively dry areas) <i>i.e.</i> Katumani in Machakos County and Naivasha in Nakuru County, Kenya, aiming to determine the combined effect of four “Zai” pit depths and two levels of manure (plots with manure and plots without manure) on selected soil properties, growth and yield of cowpea. Experiment was laid out in split plot arrangement, with manure levels as the main plot factor and “Zai” pit depths (Flat: Z<sub>0</sub>, 30 cm: Z<sub>30</sub>, 45 cm: Z<sub>45</sub> and 60 cm: Z<sub>60</sub>) as subplot factor, replicated four times. Cowpea (M66 variety) was used as the test crop. Inorganic N and extractable P were significantly (P < 0.05) higher, at 1.37 mg<span style="white-space:nowrap;"><span style="white-space:nowrap;">&sdot;</span></span>kg<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;">&minus;</span></span>1</sup> for N<sub>in</sub> and 80.4 mg<span style="white-space:nowrap;"><span style="white-space:nowrap;">&sdot;</span></span>kg<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;">&minus;</span></span>1</sup> for P<sub>ex</sub> in Zai pits compared to flat plots which were at 0.91 mg<span style="white-space:nowrap;"><span style="white-space:nowrap;">&sdot;</span></span>kg<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;">&minus;</span></span>1</sup> for N<sub>in</sub> and 47.1 mg<span style="white-space:nowrap;"><span style="white-space:nowrap;">&sdot;</span></span>kg<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;">&minus;</span></span>1</sup> for P<sub>ex</sub>. The values of N<sub>in</sub> and P<sub>ex</sub> also varied depending on depths, with Z<sub>45</sub> having highest N<sub>in</sub> at 1.17 against the least, at 0.89 in the Z<sub>0</sub>, while Pex was highest in Z<sub>30</sub> at 102.3 mg<span style="white-space:nowrap;"><span style="white-space:nowrap;">&sdot;</span></span>kg<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;">&minus;</span></span>1</sup> while Z<sub>0</sub> having the least P<sub>ex</sub> of 89.7 mg<span style="white-space:nowrap;"><span style="white-space:nowrap;">&sdot;</span></span>kg<sup><span style="white-space:nowrap;"><span style="white-space:nowrap;">&minus;</span></span>1</sup>. Generally, crops in “Zai” pitted plots were larger in diameter at 0.46 cm than crops in flat plots at 0.42 cm. Better performance was observed in yield, with Z<sub>30</sub> yielding 30.5% against 18.2% Flat plots in Machakos while 27.9% in Z<sub>30</sub> against 22.5% from Flat plots in Naivasha. This study demonstrated great potential of “Zai” pit technology on crop production, as reflected on improved growth and yield of cowpeas. Combining “Zai” pits with manure increases soil N<sub>in</sub>, P<sub>ex</sub> and is a guarantee of great crop performance in terms of high final yields. 展开更多
关键词 Zai Pits ASALs Soil Moisture Dryland Agriculture Cattle Manure Inorganic Nitrogen Extractable Phosphorus
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Soil and water conservation measures improve soil carbon sequestration and soil quality under cashews 认领
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作者 Gopal Ramdas Mahajan Bappa Das +12 位作者 Sandrasekaran Manivannan Begur Lakshminarasimha Manjunath Ram Ratan Verma Sujeet Desai Rahul Mukund Kulkarni Ashish Marotrao Latare Reshma Sale Dayesh Murgaonkar Kiran Puna Patel Shaiesh Morajkar Ashwini Desai Natasha Barnes Heena Mulla 《国际泥沙研究:英文版》 SCIE 2021年第2期190-206,共17页
Land degradation is becoming a serious problem in the west coast region of India where one of the world's eight biodiversity hotspots,the‘Western Ghats’,is present.Poor land management practices and high rainfal... Land degradation is becoming a serious problem in the west coast region of India where one of the world's eight biodiversity hotspots,the‘Western Ghats’,is present.Poor land management practices and high rainfall have led to increasing problems associated with land degradation.A long-term(13-year)experiment was done to evaluate the impact of soil and water conservation measures on soil carbon sequestration and soil quality at three different depths under cashew nut cultivation on a 19%slope.Five soil and water conservation measures-continuous contour trenches,staggered contour trenches,halfmoon terraces,semi-elliptical trenches,and graded trenches all with vegetative barriers of Stylosanthes scabra and Vetiveria zizanoides and control were evaluated for their influence on soil properties,carbon sequestration,and soil quality under cashews.The soil and water conservation measures improved significantly the soil organic carbon,soil organic carbon stock,carbon sequestration rate and microbial activity compared to the control condition(without any measures).Among the measures tested,continuous contour trenches with vegetative barriers outperformed the others with respect to soil organic carbon stock,sequestration rate,and microbial activity.The lower metabolic quotient with the measures compared to the control indicated alleviation of environmental stress on microbes.Using principal component analysis and a correlation matrix,a minimum dataset was identified as the soil available nitrogen,bulk density,basal soil respiration,soil pH,acid phosphatase activity,and soil available boron and these were the most important soil properties controlling the soil quality.Four soil quality indices using two summation methods(additive and weighted)and two scoring methods(linear and non-linear)were developed using the minimum dataset.A linear weighted soil quality index was able to statistically differentiate the effect of soil and water conservation measures from that of the control.The highest value of the soil quality index 展开更多
关键词 Land degradation Microbial activity Microbial biomass carbon Minimum dataset Soil erosion Western Ghats
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Predicting soil erosion hazard in Lattakia Governorate (W Syria) 认领
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作者 Mohammed Safwan Khallouf Alaa +5 位作者 Alshiehabi Omran Bao Pham Quoc Thi Thuy Linh Nguyen Nam Thai Van Tran Anh Duong Harsányi Endre 《国际泥沙研究:英文版》 SCIE 2021年第2期207-220,共14页
The main objective of this study is to predict soil erosion in the Lattakia Governorate(WSyria)using the Water Erosion Prediction Project model(WEPP)and to compare the result with that of the RUSLE.Field survey and da... The main objective of this study is to predict soil erosion in the Lattakia Governorate(WSyria)using the Water Erosion Prediction Project model(WEPP)and to compare the result with that of the RUSLE.Field survey and data collection were carried out,and 44 soil samples were analyzed.In addition,all the necessary input files were prepared for use in the WEPP model and RUSLE.Results show that more than of 80%of the locations studied experience slight to moderate erosion(less than 5 t/ha/y),whereas the rest of the locations experience severe soil erosion hazard.Moreover,the volume of runoff estimated by the WEPP model is in the range of 51e321 mm,and the R^2 between the simulated soil erosion and the predicted runoff reached 0.68.Interestingly,the R^2 between the WEPP model and RUSLE is 0.56,which indicates a good correlation between the two models. 展开更多
关键词 Soil erosion RUN-OFF WEPP RUSLE SYRIA
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水稻、小麦与土壤中重金属Cd含量的关系模拟研究 认领
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作者 于灏 苏智杰 +3 位作者 祝培甜 陈勇 杨侨 赵中秋 《地学前缘》 EI CAS 北大核心 2021年第1期438-445,共8页
土壤污染防治工作已成为提升耕地质量、保护国土生态安全的重要任务之一。为了科学预测我国大宗农作物(如水稻、小麦)与土壤重金属含量的关系,减少安全利用类农用地的大量农产品与土壤的协同监测,实现重金属污染农用地的安全利用,本研... 土壤污染防治工作已成为提升耕地质量、保护国土生态安全的重要任务之一。为了科学预测我国大宗农作物(如水稻、小麦)与土壤重金属含量的关系,减少安全利用类农用地的大量农产品与土壤的协同监测,实现重金属污染农用地的安全利用,本研究以重金属Cd为例,选取对水稻、小麦Cd含量影响较大的土壤Cd含量、土壤pH值、土壤阳离子交换量(CEC)和土壤有机碳(OC)含量作为输入因子,水稻、小麦Cd含量作为输出因子,分别建立了多元回归模型与神经网络模型。结果表明:水稻、小麦Cd含量与土壤Cd含量呈现正相关关系;模拟出的水稻、小麦与土壤Cd的多元线性回归模型的预测能力分别为67.8%和83.8%;利用神经网络构建了水稻、小麦Cd含量预测模型,在训练集、验证集和测试集中都表现出很好的预测能力,R值均大于多元线性回归模型,且MSE(均方误差)值较小,神经网络对水稻、小麦Cd含量预测具有很好的适用性,模拟精度总体优于多元回归预测模型。研究结果可为污染农用地的安全利用评价及优化配置提供一定的理论依据和参考。 展开更多
关键词 土壤 水稻 小麦 预测模型 神经网络
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宁夏草原针茅属植物群落物种多样性和生产力格局及影响因素研究 认领
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作者 刘万弟 李小伟 +3 位作者 黄文广 马惠成 马红英 王文晓 《草业学报》 北大核心 2021年第1期12-23,共12页
物种多样性和生产力是草地生态系统的核心指标,是实现草地生态系统服务与功能的根本所在。宁夏温性草原位于干旱与半干旱的过渡区,针茅属植物是其优势种群,对水热变化敏感;因此,在全球气候变化背景下,探讨宁夏草原针茅属植物群落物种多... 物种多样性和生产力是草地生态系统的核心指标,是实现草地生态系统服务与功能的根本所在。宁夏温性草原位于干旱与半干旱的过渡区,针茅属植物是其优势种群,对水热变化敏感;因此,在全球气候变化背景下,探讨宁夏草原针茅属植物群落物种多样性与生产力的格局,在宏观尺度揭示其影响因素,不仅在生态学理论研究中具有重大价值,而且对宁夏天然草地生产与管理也具有指导意义。本研究以宁夏温性草原针茅属植物群落为对象,沿着环境梯度设置15个野外观测样地,调查了植物群落特征,测定土壤养分指标,结合各个样地的气候因子、土壤养分和空间数据,探讨了植物群落多样性和生产力空间分布格局及其对生态因子的响应,阐明植物群落物种多样性与生产力的关系。结果显示:1)宁夏针茅属群落生产力与纬度呈显著正相关,与海拔和经度显著负相关;物种多样性与纬度显著负相关,与海拔显著正相关,而与经度关系不显著;2)冗余分析(RDA)结果显示:土壤速效氮(SAN)、年均温度(MAT)、土壤有机碳(SOC)、土壤全氮(TN)、年均辐射(Ssrad)、土壤水分(SWC)、土壤容重(BD)、土壤全磷(TP)、年均降水量(MAP)、生长季月均降水量(GSP)、干旱季月均降水量(PDA)是影响物种多样性和生产力的主要因素;土壤因子对生产力、多样性及整体解释量分别为15.6%、17.8%、19.8%,水热因子对生产力、多样性及整体解释量分别为13.8%、37.9%、25.2%,共同解释量分别为68.7%、39.6%、50.6%。总体而言,水热及土壤因子是宁夏针茅属草原生产力及多样性格局的驱动因素,但对多样性和生产力解释比例不同,具有一定的倾向性;群落多样性与生产力呈正相关趋势,但不显著。本研究结果能为宁夏天然草原的生产与管理提供理论依据。 展开更多
关键词 针茅属群落 多样性 生产力 水热条件 土壤
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宁夏盐池县荒漠草原区不同群落优势植物叶片-土壤生态化学计量特征 认领
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作者 聂明鹤 沈艳 +2 位作者 陆颖 王科鑫 张小菊 《草地学报》 CAS 北大核心 2021年第1期131-140,共10页
为分析宁夏荒漠草原区不同群落植物与土壤的碳(Carbon,C)、氮(Nitrogen,N)、磷(Phosphorus,P)含量及其比值特征,本研究以宁夏盐池县荒漠草原区8种群落的植被及土壤为对象,研究了不同群落优势植物与土壤生态化学计量特征及其相互关系。... 为分析宁夏荒漠草原区不同群落植物与土壤的碳(Carbon,C)、氮(Nitrogen,N)、磷(Phosphorus,P)含量及其比值特征,本研究以宁夏盐池县荒漠草原区8种群落的植被及土壤为对象,研究了不同群落优势植物与土壤生态化学计量特征及其相互关系。结果表明:与全球平均水平相比,研究区不同群落优势植物叶片与土壤的C,N,P含量均较低;不同群落优势植物叶片与土壤的生态化学计量特征不同;苦豆子(Sophora alopecuroides)群落、短花针茅(Stipa breviflora)群落、赖草(Leymus secalinus)群落与白刺(Nitraria tangutorum)群落的限制植物生长的元素主要是P,甘草(Glycrrhiza uralensis)群落、中亚白草(Pennisetum centrasiaticum)群落和油蒿(Artemisia ordosica)群落植物的生长限制元素主要是N,N与P元素共同限制牛枝子(Lespedeza potaninii)群落的植物生长;土壤总C含量与植物总C含量具有极显著的正相关关系(P<0.01),与土壤全N和全P含量呈显著正相关(P<0.05);植物总C含量与土壤全P含量呈显著正相关(P<0.05)。 展开更多
关键词 宁夏盐池县 荒漠草原 植物群落 优势植物 土壤 生态化学计量
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土壤及肥料类型对蔬菜重金属累积的影响 认领
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作者 高丽 杨欣悦 +1 位作者 赵家印 席运官 《安徽农业科学》 CAS 2021年第2期59-62,共4页
为探索不同重金属含量的土壤和不同施肥对不同蔬菜重金属累积的影响,开展了铜镉超标的昆明市周边蔬菜地土壤和不超标的南京市周边蔬菜地土壤,在施用有机肥和化肥的情况下,辣椒、番茄、菜薹、芥蓝的可食部分对铜镉累积的盆栽试验。结果表... 为探索不同重金属含量的土壤和不同施肥对不同蔬菜重金属累积的影响,开展了铜镉超标的昆明市周边蔬菜地土壤和不超标的南京市周边蔬菜地土壤,在施用有机肥和化肥的情况下,辣椒、番茄、菜薹、芥蓝的可食部分对铜镉累积的盆栽试验。结果表明,铜作为作物的必需营养元素,在一定范围内,土壤铜的含量不会显著影响番茄、菜薹、芥蓝对铜的累积,相比化肥,有机肥的施用能够促进番茄、辣椒对铜的累积(分别高54.0%、45.9%),但降低菜薹、芥蓝对铜的累积;镉是作物的有害元素,在化肥施用条件下,菜薹、芥蓝、辣椒、番茄Cd累积都是重金属超标土壤显著高于非超标土壤(分别提高50.1%、51.3%、155.0%和11.1%),叶菜的累积高于茄果类,相比化肥,重金属超标土壤中有机肥的施用可抑制菜薹和辣椒对Cd的吸收与累积(分别降低22.8%和34.9%)。 展开更多
关键词 蔬菜 土壤 施肥 重金属累积 影响
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樟子松人工林生长对土壤碳氮磷化学计量的影响 认领
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作者 李尧 雷泽勇 +2 位作者 于东伟 张岩松 白津宁 《安徽农业科学》 CAS 2021年第2期91-94,共4页
以科尔沁沙地不同生长期(幼林、中龄林、成熟林、过熟林)的樟子松人工林为对象,研究0~100 cm层土壤碳氮磷化学计量随林龄的变化规律。结果表明:樟子松人工林土壤C/N含量表现为过熟林>中林龄>幼林龄>成熟林,C/P含量表现为过熟林... 以科尔沁沙地不同生长期(幼林、中龄林、成熟林、过熟林)的樟子松人工林为对象,研究0~100 cm层土壤碳氮磷化学计量随林龄的变化规律。结果表明:樟子松人工林土壤C/N含量表现为过熟林>中林龄>幼林龄>成熟林,C/P含量表现为过熟林>幼林龄>中林龄>成熟林,N/P随着林龄增加先降低后升高,C/P、C/N、N/P含量最低值均出现在生长速度最快的成熟林,最高值均出现在过熟林。表明沙地樟子松人工林在成熟林以前,土壤磷含量满足樟子松人工林的生长需求。在过熟林阶段碳含量出现累积,土壤磷增长量低于碳增长量,致使过熟林时期樟子松人工林增长速率下降,磷成为过熟林时期樟子松生长限制因子。 展开更多
关键词 樟子松 林龄 土壤 化学计量
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关中地区典型土壤和污泥中多氯联苯的分布特征 认领
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作者 刘婉玉 袁琪 王森 《西北大学学报:自然科学版》 CAS 北大核心 2021年第1期33-42,共10页
多氯联苯(polychlorinated biphenyls,PCBs)是一类环境中广泛存在的全球性有机污染物。该文以关中地区固体废弃物处置区土壤和污水处理厂污泥为研究对象,探究典型污染土壤和污泥中PCBs同系物的分布特征。结果表明,固体废弃物处置区土壤(... 多氯联苯(polychlorinated biphenyls,PCBs)是一类环境中广泛存在的全球性有机污染物。该文以关中地区固体废弃物处置区土壤和污水处理厂污泥为研究对象,探究典型污染土壤和污泥中PCBs同系物的分布特征。结果表明,固体废弃物处置区土壤(4.26~57.77 ng/g(avg,15.31 ng/g))和污泥中(9.64~213.85 ng/g(avg,53.65 ng/g))∑PCBs在国内外均处于中等偏低水平,76.47%的土壤样品中∑PCBs低于荷兰农业土壤容许标准值(20 ng/g),94.12%的污泥样品中∑PCBs低于我国城市污泥农用控制标准(200 ng/g dw)。土壤和污泥中分别检测到36和33种PCBs单体,其中三氯代和四氯代PCBs所占比例最高。主成分分析结果表明关中地区污泥中PCBs可能源于国产变压器油或进口PCBs商品。研究结论以期为土壤和污泥中PCBs的污染与控制提供基础数据和科学依据。 展开更多
关键词 关中地区 土壤 污泥 多氯联苯 分布特征
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草莓连作障碍绿色防控研究进展 认领
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作者 戚嘉琦 周怡 +3 位作者 陈冉 吴欣欣 胡珍珠 陈伯清 《中国果菜》 2021年第1期69-73,共5页
土壤连作障碍是草莓生产中最主要的瓶颈问题之一,对草莓植株的生长及果实产量、品质都有不良影响,严重妨碍了草莓产业的健康发展。本文探讨了草莓连作障碍的成因,对草莓连作障碍的危害进行了分析,并对近年来的防治方法进行了总结,提出... 土壤连作障碍是草莓生产中最主要的瓶颈问题之一,对草莓植株的生长及果实产量、品质都有不良影响,严重妨碍了草莓产业的健康发展。本文探讨了草莓连作障碍的成因,对草莓连作障碍的危害进行了分析,并对近年来的防治方法进行了总结,提出了草莓连作障碍未来的防治方向。 展开更多
关键词 草莓 连作障碍 土壤 成因 克服技术
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两种干燥方式对土壤中多环芳烃回收率及同分异构体比值的影响 认领
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作者 何坤 谢忠雷 +2 位作者 高传宇 靳前 王国平 《吉林大学学报:理学版》 CAS 北大核心 2021年第1期175-182,共8页
通过实验室模拟向泥炭土和农田土添加不同量的外源多环芳烃单体标准物质,经冷冻干燥和自然风干处理后,用气相色谱-质谱法(GC-MS)对土壤中16种外源多环芳烃单体进行测定,分析两种干燥方式对土壤外源多环芳烃回收率和同分异构体比值的影响... 通过实验室模拟向泥炭土和农田土添加不同量的外源多环芳烃单体标准物质,经冷冻干燥和自然风干处理后,用气相色谱-质谱法(GC-MS)对土壤中16种外源多环芳烃单体进行测定,分析两种干燥方式对土壤外源多环芳烃回收率和同分异构体比值的影响,以反映不同干燥方式下土壤中多环芳烃测定的准确度及自然土壤多环芳烃来源判定的差异.实验结果表明:泥炭土随外源多环芳烃添加量的增加,多环芳烃总量回收率呈先降低后增加的趋势,在相同添加量下,风干处理的多环芳烃总量回收率(56.29%~80.15%)均高于冻干处理的回收率(52.82%~78.31%),泥炭土单体多环芳烃低环组分风干处理高于冻干处理的回收率,高环组分冻干处理高于风干处理的回收率;不同干燥方式处理下农田土中多环芳烃总量回收率差异显著(P<0.05),经冻干处理后的总量回收率为64.40%~73.81%,经风干处理后的总量回收率为40.88%~57.01%,其单体多环芳烃冻干处理均高于风干处理的回收率;两种土壤的有机质质量比和含水率不同可能是导致多环芳烃总量和单体回收率差异的主要因素;在两种干燥方式处理下,泥炭土中不同多环芳烃同分异构体比值无显著差异,农田土中多环芳烃同分异构体比值受干燥方式影响显著. 展开更多
关键词 土壤 干燥方式 多环芳烃 回收率 同分异构体比值
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根系分泌物对砷酸还原菌TS28活性及土壤中酶活性的影响 认领
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作者 郭平 徐富凯 +3 位作者 刘亦博 李美璇 封保根 陈薇薇 《吉林大学学报:理学版》 CAS 北大核心 2021年第1期183-189,共7页
以砷酸还原菌(Stenotrophomonas sp.TS28)以及油菜、小麦和小白菜的根系分泌物为实验对象,研究根系分泌物对砷(As)污染土壤中砷酸还原菌TS28存活、As还原能力的影响以及土壤中酶活性的变化规律.结果表明:土壤中的As(Ⅴ)抑制了TS28的活性... 以砷酸还原菌(Stenotrophomonas sp.TS28)以及油菜、小麦和小白菜的根系分泌物为实验对象,研究根系分泌物对砷(As)污染土壤中砷酸还原菌TS28存活、As还原能力的影响以及土壤中酶活性的变化规律.结果表明:土壤中的As(Ⅴ)抑制了TS28的活性,添加根系分泌物刺激了TS28的活性,增加了TS28的存活数量和存活时间;植物根系分泌物会影响TS28的As还原能力,影响程度与其来源有关,小麦的根系分泌物对TS28的As还原能力提升效果最好,10 d内将As(Ⅴ)的还原量提升了45.86%;TS28降低了As污染土壤中蔗糖酶和脱氢酶的活性,添加根系分泌物提高了含TS28的As污染土壤中脲酶、酸性磷酸酶、蔗糖酶和脱氢酶这4种土壤酶的活性,油菜根系分泌物的促进效果最好. 展开更多
关键词 根系分泌物 土壤 砷酸还原菌 存活 还原 酶活性
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土壤与初烤烟叶成分及烤烟品质的相关性分析 认领
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作者 赵鹏力 申洪涛 +5 位作者 徐辰生 王艳芳 张仕祥 刘德鸿 刘领 杨自军 《河南科技大学学报:自然科学版》 CAS 北大核心 2021年第2期82-87,93,M0007,共8页
为了探讨植烟区土壤成分对烤烟基础化学成分及品质的影响,选择南平K326植烟品种为材料,测定土壤和烟叶中基础成分含量,分析其与评吸结果的关联性。研究结果表明:土壤碱解氮和速效磷含量与C3F烤烟烟碱有较高的正相关性(r>0.64),土壤... 为了探讨植烟区土壤成分对烤烟基础化学成分及品质的影响,选择南平K326植烟品种为材料,测定土壤和烟叶中基础成分含量,分析其与评吸结果的关联性。研究结果表明:土壤碱解氮和速效磷含量与C3F烤烟烟碱有较高的正相关性(r>0.64),土壤有机质与烤烟总氮、总糖、还原糖含量有正相关性(r>0.72)。C3F烤烟透发性与土壤速效钾呈强正相关性(r>0.96),与烤烟总氮、钾含量呈较强正相关性(r>0.65)。B2F烤烟透发性与总氮(r>0.84)、糖含量(r>0.74)有正相关性。说明土壤营养物质影响烤烟中的化学成分含量,同时影响初烤烟叶的品质,且与等级有关联。烤烟中总氮、钾、烟碱和总糖含量及其之间的比例关系与烤烟的透发性有关。 展开更多
关键词 南平市 土壤 烤烟 品质 透发性
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生物有机肥对烟株根系及土壤理化性质的影响 认领
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作者 钟泽林 冯文龙 +3 位作者 余伟 张宗锦 闫芳芳 周欢 《安徽农业科学》 CAS 2021年第2期138-142,146,共6页
通过田间试验,研究了生物有机肥对烟株根系及土壤理化性质的影响。结果表明,施用全元生物有机肥对不同肥力土壤上烟株不同生育期根系生长均有促进作用;可有效调整不同肥力土壤的酸碱度,提高土壤含水量,增加土壤有机碳、微生物量碳和微... 通过田间试验,研究了生物有机肥对烟株根系及土壤理化性质的影响。结果表明,施用全元生物有机肥对不同肥力土壤上烟株不同生育期根系生长均有促进作用;可有效调整不同肥力土壤的酸碱度,提高土壤含水量,增加土壤有机碳、微生物量碳和微生物量氮;有效调节不同肥力土壤中根际微生物的多样性和群落结构。其中,全元生物有机肥2250 kg/hm 2+复合肥255 kg/hm 2是改善土壤理化性质、增加根系生长、改善烟株生长的土壤生态环境的最佳标准。 展开更多
关键词 生物有机肥 根系 土壤 理化性质
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不同磷肥对水稻根表铁膜及砷镉吸收的影响——以石灰岩黄壤性水稻土为例 认领
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作者 赵婷婷 王春丽 赵秀兰 《中国环境科学》 EI CAS 北大核心 2021年第1期297-306,共10页
为寻求砷(As)镉(Cd)复合污染稻田安全利用的有效措施,以贵州石灰岩区As、Cd复合污染黄壤性水稻土为材料,采用盆栽试验,研究了6种磷肥对土壤As、Cd有效性、水稻根表铁膜及As、Cd吸收的影响.结果表明:与对照相比,羟基磷灰石(HAP)、生物酶... 为寻求砷(As)镉(Cd)复合污染稻田安全利用的有效措施,以贵州石灰岩区As、Cd复合污染黄壤性水稻土为材料,采用盆栽试验,研究了6种磷肥对土壤As、Cd有效性、水稻根表铁膜及As、Cd吸收的影响.结果表明:与对照相比,羟基磷灰石(HAP)、生物酶活性磷肥(BCP)、钙镁磷肥(CMP)处理使土壤pH值显著提高,磷酸二氢钙(MCP)、磷酸二氢钾(MKP)、过磷酸钙(SSP)处理使土壤pH值显著降低.所有磷肥处理均降低了土壤有效Fe含量,其中HAP、MCP、CMP的降低效果显著.HAP显著降低了土壤有效Cd和有效As含量;MCP和BCP显著提高土壤有效Cd含量,但对土壤有效As无显著影响;SSP显著降低了土壤有效Cd含量,但显著提高土壤有效As含量.不同磷肥使水稻根表铁膜数量提升0.6%~27.1%,铁膜数量与铁膜中Cd、As含量分别呈极显著(R^2=0.555**)和显著(R^2=0.525*)正相关关系.MCP、MKP、BCP显著降低了糙米Cd、As含量,HAP、SSP、CMP显著降低了糙米Cd含量,但对糙米As含量无显著影响.磷肥均使Cd叶→颖壳的转运系数下降,MKP、MCP能抑制As从根到茎的转运,BCP能抑制As从叶到颖壳的转运.磷肥降低水稻糙米Cd、As含量与铁膜数量增加、水稻体内Cd、As转运变化有关. 展开更多
关键词 磷肥 As/Cd 土壤 水稻 铁膜
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