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1.
The concentration of edaphic and foliar nutrients is an important factor in assessing the nutritional status of an ecosystem. This article presents data on the macronutrients in leaves and topsoil in Quercus robur forests located in northwest Spain. The aim is to evaluate the nutrient level explained by foliar and soil standard values and establish their relationships. We calculated the following nutrients: nitrogen, phosphorus, potassium, calcium, and magnesium. Plots 10 × 10 m were laid out and replicated three times. Soil was collected once per month with three samples from the topsoil, and leaves were collected once every 2 months during the vegetative period. Within the results, we emphasize the absence of nutrient deficiencies. The leaf macronutrient results differed by stand. Soil fertility can be considered low to medium, except for phosphorus and potassium, as compared with soils under pine and eucalyptus. There was no relationship between macronutrients in topsoil and leaves.  相似文献   

2.
通过对设置在辽东山区本溪市草河口镇和庄河市仙人洞镇两个典型天然次生栎林(Quercus spp.)样地内的土样进行分层(0—10,10—20,20—30,30—40cm)采集和室内分析,研究了0—40cm土层土壤有机碳、全氮、全磷等含量的剖面分布特征,探讨了有机碳与理化性质间的关系。结果表明:土壤有机碳及全氮、全磷、全钾、碱解氮、速效磷、速效钾、阳离子交换量的含量均随土层加深而降低,而土壤容重随土层加深而增加,由t检验和方差分析得知,各指标含量在土层间差异均达到5%显著水平;土壤有机碳与粉粒、pH、全氮、全磷、全钾、碱解氮、速效磷、速效钾、阳离子交换量间均呈显著正相关(r=0.430 9~0.919 0,n=44,P0.01),与土壤容重、砂粒间均呈显著负相关(r=0.388 3~0.670 6,n=44,P0.01),而与黏粒间无显著相关性;由逐步回归分析得知土壤碱解氮、碳氮比、全钾、pH、全氮与有机碳间关系最为紧密。土壤有机碳与其他理化性质间关系密切,且以全氮、碱解氮、碳氮比、全钾和pH对其影响最大;同时,各指标均具有明显的剖面分布规律。  相似文献   

3.
The main edaphic properties of the natural forests of rebollo oak (Quercus pyrenaica Willd.) in Galicia (NW Spain) were calculated. Forty soils distributed throughout the study area were sampled, and 10 edaphic parameters [four were related to chemical properties –pH, organic matter (OM), nitrogen (N), and carbon (C)/N ratio; four were related to soil fertility, phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg); and two to physical characteristics, fine earth and gravel, were estimated. Siliceous substrates were present in most of the stands, with schist and quartzite predominating, and the soils were basically Regosols. The values of soil chemical properties were similar to those reported as optimal values for oak forests [Quercus robur L. and Q. petraea (Matt.) Liebl.] in the study area (i.e., pH close to 5, OM approximately 4, C/N ratio approximately 18). The concentration of macronutrients, except phosphorus (9.4 ppm versus 21.8 ppm), can be considered high as compared with soils under Q. robur. With respect to physical characteristics, the dominant texture was sandy-loam and the gravel content was approximately 40%, with maximum values of more than 70%. The application of Principal Components Analysis to the parameters gave rise to four new variables which may explain nearly 83% of soil variability.  相似文献   

4.
Massive forest damage has been observed in certain mountainous regions affected by acidification. Declining of trees is ascribed to direct effect of SO2 and also increasing concentration of mobile forms of Al in soils. The aim of this paper is to describe the influence of stand factors to distribution of Al forms in the Jizera Mountains region, Czech Republic. A set of 251 samples from 98 sites was collected. Basic soil characteristics and the content of different Al forms were determined. The amount and relative share of these Al forms under different types of vegetation was evaluated, with emphasis on the surface organic horizons. The results showed that phytotoxic mobile Al forms are the most influenced by altitude and organically bound Al forms by forest type. Non-toxic forms of Al are more abundant in broadleaved forest. Soils under coniferous forest are more affected by acidification.  相似文献   

5.
In 2006, the International Organization of Christian Charities (IOCC) began a program in the country of Georgia to establish an improved dairy enterprise in the villages of Minadze and Ghreli in the Akhaltsikhe district. To correctly determine the fertility requirements for the use of either mineral or organic fertilizer materials for improving soil fertility for legume grain crops (beans, peas, soybeans, etc.) and perennial pastures (a mixture of perennial cereal grasses and perennial legumes) and for the proper management of these soils, it was necessary to understand the geomorphic, chemical, and physical characteristics of the soils of this region. Soils of this region belong to a subtype of Cinnamonic Calcareous soils. The characteristics of these soils as well as their fertility and soil management needs were ascertained. Appropriate amounts of mineral and organic fertilizers needed for the proper growth of legume crops and perennial pastures as well as timing of application are presented.  相似文献   

6.
对不同植被、不同利用方式下广东丘陵红壤水分性能进行了比较研究.结果表明,与自然地带性植被下的赤红壤比较,次生植被、人工植被下红壤类土壤导水性、持水能力和供水能力一般均较低.在同样的吸力下,次生植被、人工植被下红壤类土壤持水量较少,在同样吸力段.土壤释放的水量较少.玄武岩砖红壤持水量较大,但土壤水分有效性低.研究表明.广东丘陵旱地土壤局部干旱的发生,与其本身的土壤水分性能有密切关系,改良土壤水分性状,是调控广东丘陵旱地土壤水分的重要环节.  相似文献   

7.
西北典型林地和农田土壤锌的吸附-解吸特性研究   总被引:3,自引:0,他引:3  
采集我国西北地区的黄绵土、土娄土和石灰性褐土3种典型土壤,分别包括农田和自然林地土壤,通过不同土壤类型及利用方式的比较,研究这三类土壤对锌的吸附-解吸特性。结果表明,各土壤对锌的吸附量均随平衡液锌浓度的增加而增大,均可用Langmuir方程、Freundlich方程和Temkin方程来描述,相关系数均达到显著或极显著水平;土壤对锌的解吸量随吸附量的增大而增加。在3种土壤中土娄土对锌的最大吸附量、最大缓冲容量以及对锌的吸附作用力以及固定量都最大;石灰性褐土对锌的最大吸附量大于黄绵土,而黄绵土对锌的最大缓冲容量、吸附作用力和固定量大于石灰性褐土。3种土壤对锌的吸附和解吸曲线有明显的相似性,自然林地土壤改为农田利用后,土壤对锌吸附-解吸性质均有一定的变化,但变化不是太大。  相似文献   

8.
[目的]研究衡阳市紫色土丘陵坡地恢复对土壤酶活性及理化性质的影响,以揭示不同恢复阶段土壤性质的变化、土壤生态系统的恢复/退化机理。[方法]采用时空互代方法,分析草本(Ⅰ)、灌草(Ⅱ)、灌丛(Ⅲ)和乔灌群落(Ⅳ)阶段的0—10cm,10—20cm和20—40cm土层的土壤酶活性和理化性质变化。[结果](1)不同恢复阶段的Patrick指数(R)、Shannon—Wiener指数(H)的大小顺序为:ⅢⅣⅡⅠ,Simpson指数(D)排序为:ⅠⅡⅣⅢ,Evenness指数(E)排序为:ⅣⅢⅡⅠ,各植被地上和地下生物量均显著增加;(2)随着植被恢复过程的进行,土壤含水量(SWC)、土壤有机质(SOM)、全氮(TN)、全磷(TP)、硝态氮(NO-3—N)和有效磷(AP)含量明显上升,土壤容重(SBD)、pH值及根土比(R/S)逐渐减小。随着土壤深度增加,SWC,R/S,SOM以及N,P养分等明显下降,而SBD和pH值逐渐增大;(3)随着恢复进行,脲酶(URE)、蛋白酶(PRO)、碱性磷酸酶(APE)、蔗糖酶(INV)、纤维素酶(CEL)和多酚氧化酶(PPO)活性明显上升,过氧化氢酶(CAT)活性以Ⅲ最高。除PPO和CAT外,其他土壤酶活性随土壤深度加深显著减小。[结论]植被恢复可改善土壤理化性质和提高土壤酶活性。  相似文献   

9.
陕北石油污染对土壤理化性质的影响   总被引:7,自引:1,他引:7  
为了研究石油污染对土壤理化性质的影响,对安塞县8个类型油井井场周围土壤中的石油烃含量和理化性质进行分析测定。结果表明,井场周围土壤石油烃含量变化范围为0.08~71.49 g/kg,其中井场外0~5 m区域和5~20 m区域内土壤污染严重。石油污染导致土壤含水率、pH值、硝态氮、速效磷、全钾和速效钾含量显著降低,容重、有机质和铵态氮含量显著升高,全氮和全磷含量无显著变化;石油污染土壤中的石油烃含量与含水率、容重、有机质、铵态氮、速效磷和速效钾均呈极显著相关,与pH值和全钾呈显著相关,与全氮、硝态氮和全磷无显著相关关系。  相似文献   

10.
The physical and chemical properties of Arctic tundra soils were studied along a 250-km latitudinal transect in northern Alaska. The transect includes the nonacidic tundra of the Arctic Coastal Plain, the moist nonacidic tundra of the northern Arctic Foothills, and moist acidic tundra of the southern Arctic Foothills. The parent material of the coastal plain consists of carbonate-rich alluvium. The northern foothills have a mantle of calcareous loess. Further south the parent materials are moraines of late Quaternary. Vegetation changes from sedges on the coastal plain, to grasses on the northern foothills, and tussock and shrub tundra in southern foothills. Following the same order, soil pH and base saturation decrease and soil acidity increases. Most of the soil exchangeable acidity and cation exchange capacity are from soil organic matter.  相似文献   

11.
Abstract

Eighty four soil samples collected from southeastern Norway were analyzed for Cd by extraction with NH4OAc, DTPA, NH4OAc-EDTA, NH4NO3, HCl and CaCl2. The total Cd, pH, exchangeable K and Ca, dithionite-extractable Mn, available P and fine sand (0.2–0.02 mm) contents were the principal factors related to the extractable Cd, with some inter-extractant variations. Cadmium extracted by NH4NO3, NH4OAc, HCl and CaCl2 decreased with increasing soil pH, but the Cd extracted by all the extractants increased with increasing total Cd, exchangeable K and Ca, available P, and Mn-oxide contents in the soils. The Cd concentrations in plants were significantly related to the extractable Cd, exchangeable Ca and Mg, pH, Mn-oxides and organic matter content.  相似文献   

12.
不同耕作模式对稻田土壤理化性质及经济效益的影响   总被引:6,自引:0,他引:6  
董建江  邵伏文  张林  姜超强  祖朝龙 《土壤》2015,47(3):509-514
为研究不同耕作模式对土壤理化性状和作物经济效益的影响,对皖南地区4种典型耕作模式(单季稻种植、油稻轮作、麦稻轮作、烟稻轮作)的土壤和作物产量进行了研究。结果表明:与单季稻种植相比,轮作显著降低了土壤含水量;麦稻轮作和烟稻轮作土壤体积质量显著增加,孔隙度显著降低;麦稻轮作土壤有机质和碱解氮含量分别显著降低35.8%和47.8%;烟稻轮作土壤速效钾含量显著增加68.2%,速效磷含量提高109.5%。油稻轮作和烟稻轮作总产值比单季稻种植分别显著增加35.3%和155.5%。为解决轮作对土壤的不良影响,要注重增施有机肥和秸秆还田以改善土壤体积质量和孔隙度;麦稻轮作应重点解决土壤p H降低的问题;烟稻轮作要减少烟后晚稻的磷肥和钾肥施用量。总体而言,油稻轮作和烟稻轮作是皖南地区维护农田土壤肥力,促进农业可持续发展,实现农业增产增收的重要耕作模式。  相似文献   

13.
重庆缙云山典型林分土壤结构分形特征   总被引:6,自引:0,他引:6       下载免费PDF全文
 为了解长江三峡库区森林土壤的物理性质,运用分形原理,研究重庆缙云山4种典型林分林地土壤分形特征,建立土壤结构分维与土壤性质预测模型,运用弹性分析与边际分析,探讨土壤结构分形变化与土壤性质变化的关系。研究表明:土壤机械组成分维、微团聚体组成分维和孔隙组成分维可作为评价土壤结构的指标。不同林分林地土壤颗粒机械组成分维值为2.7~2.9,土壤微团聚体组成分维为2.5~2.8,土壤孔隙组成分维为2.3~2.8。从质地、微团聚体组成和孔隙组成来看,常绿阔叶灌丛土壤结构要明显优于其他林地土壤,而楠竹林最差。不同林分及农地土壤的微团聚体组成、机械颗粒组成和孔隙组成分维与土壤性质存在较明显相关关系,相关系数都在0.5以上。由弹性系数和边际量可以看出,机械分维的影响要大于微团聚体分维和孔隙组分维。这对进一步探讨分形学在土壤结构与土壤性质的应用方面有重要的意义。  相似文献   

14.
施用白云石对酸性黄红壤作物产量及化学性质的影响   总被引:8,自引:0,他引:8  
白云石改良酸性黄红壤三年定位试验结果表明:酸性黄红壤施用白云石可以降低土壤交换性铝的含量,提高土壤pH值和交换性钙、镁的含量,显著提高作物产量,且有明显的后效。第1—6季作物分别增产10.8%~13.4%、21.5%~48.6%、9.4%~16.2%、10.9%~44.6%、7.9%~22.0%和6.6%~29.8%。白云石施用量为600kg hm-2时,降酸作用可维持3季作物以上;白云石施用量为2500 kg hm-2时,降酸作用可维持6季作物以上。  相似文献   

15.
16.
Soil acidification in mountainous regions of the Czech Republic presents a serious problem. This paper summarizes several projects dealing with this problem exploiting different methods and having different objectives: 1) Long-term soil and forest development in the Krkonoše Mountains. 2) Soil and forest development along an elevation transect in the Šumava Mountains. 3) Long-term effects of liming. 4) Comparison of soil acidification between three mountainous regions, with emphasis on labile Al content. 5) Spatial distribution and factors of soil acidification and Al release in the Jizera Mountains. The results of these projects showed that acidification in forest soils in the mountainous areas is caused by a combination of different factors, especially by the type of vegetation, atmospheric deposition, parent rock, altitude, and others. A slight improvement of soil properties is apparent after the decrease of immissions in the 1990's.  相似文献   

17.
Abstract

One approach to evaluating computer models which predict terrestrial‐aquatic ecosystem response to acid deposition is the experimental acidification of soils with subsequent comparisons among predicted and measured soil solution response. Using a soil microcosm experimental approach, comparisions between simulated acid rain (i.e. dilute H2SO4), dry NH4NO3, and prilled reduced S were made for suitability for large‐scale field experiments. Soil microcosms consisting of reconstructed soil profiles received a background simulated throughfall dosing over the six month treatment period. Results indicated that simulated throughfall, applied at twice the ambient rate, acidified soil leachates approximately 0.5 pH units over the treatment period. Along with the decline in leachate pH was an apparent release of base cations as well as Fe and Al. Over the length of the treatment period, very little of the prilled S dissolved and the simulated acid rain treatment did not have significant effects on leachate chemistry.  相似文献   

18.
苗桓  许加明  虞悦  卜元卿  王艮梅  周蓉 《土壤》2023,55(6):1316-1322
通过研究三种不同森林土壤中蚯蚓对莠去津暴露的响应,为莠去津在林业上的科学使用和保护生态环境提供科学依据。采用室内实验的方法研究三种不同类型的森林土壤中莠去津对蚯蚓的影响,以40、80、160、320、480 mg/kg作为暴露浓度,暴露后于第0天,第7天,第14天,第21天,第28天,第35天分别测定土壤中蚯蚓鲜重和死亡率,于第0天和第35天测定土壤中蚯蚓体宽。结果表明,三种森林土壤中莠去津暴露浓度越高,暴露时间越长,对蚯蚓致死效应越强,对蚯蚓鲜重和体宽的抑制效应也越强,呈明显的时间-效应关系和剂量-效应关系。暴露浓度相同时,三种土壤中莠去津对蚯蚓死亡率、鲜重和体重的影响均表现为黄棕壤>雏形土>石灰土。莠去津对蚯蚓的毒性效应与土壤中有机质的含量之间具有明显负相关性,与全磷和有效磷的含量之间具有明显正相关性。研究结果揭示不同类型土壤中莠去津对蚯蚓的毒性作用具有明显差异,且与土壤的肥力具有显著相关性,其可为评估莠去津在农林业上使用的环境风险提供基础参考数据。  相似文献   

19.
鲁中南石灰岩山地针阔混交林土壤理化性状及水文效应   总被引:4,自引:0,他引:4  
为选择出适宜鲁中南石灰岩山地的针阔混交林模式,以山东省新泰市扒石山小流域栽植的5种10a生针阔混交林为研究对象,采用野外调查与室内测定相结合的方法,系统分析针阔混交林模式下的枯落物蓄积量、土壤理化性质、土壤渗透速率、土壤水文效应等指标,研究不同针阔混交林对林地土壤理化性状和土壤水文效应的改良效果。结果表明:5种混交林模式下的各项指标均差异显著,且针阔混交林的各项指标均优于侧柏纯林,其中针阔混交林的各项指标均以侧柏刺槐混交林最优,侧柏黄连木混交林较差;林地土壤理化性状和水文效应的改良效果依次为:侧柏刺槐混交林侧柏苦楝混交林侧柏五角枫混交林侧柏臭椿混交林侧柏黄连木混交林。在鲁中南石灰岩山地营造针阔混交林时,应优先选择侧柏刺槐混交林和侧柏苦楝混交林,其次可选择侧柏五角枫混交林和侧柏臭椿混交林,应尽量避免大面积营造侧柏黄连木混交林及侧柏纯林。  相似文献   

20.
Zinc (Zn) sorption curves were established for 11 cultivated sandy soils from central Vietnam. Soil samples (10 g) were equilibrated with 5 mM calcium chloride (CaCl2) solutions (50 mL) at five zinc chloride (ZnCl2) concentrations (0 to 80 mg Zn L–1). The experimental sorption data were fitted with the Freundlich equation. The amounts of Zn sorbed by soil (QZn) at different Zn concentrations in the equilibrium solution (CZn) were closely related to cation exchange capacity (CEC) and pH, that is, to the available exchange sites at given pH values. More specifically, an excellent correlation was found between Zn sorption and exchangeable calcium (Caex), which evidently also depends on CEC and pH. A unique equation was proposed to predict QZn from CZn and Caex in the range of Zn loading covered in our research, that is, from traces to QZn ≈ 60 mg Zn kg–1.  相似文献   

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