Changes in the content of humus in gray forest soils under long-term fertilization

The effect of different fertilizing systems on the content of humus in gray forest soils of the Opolie region has been studied during three cycles of eightand seven-course crop rotations. At the application of phosphorus–potassium fertilizers and without fertilization, the content of humus in the plow layer has decreased by 0.02% annually in the first rotation cycle and by 0.011% in the second and third cycles. In the first cycle, the addition of 1 t of litter manure and 1 kg of nitrogen increased the humus content by 55 and 9.8 kg, respectively; in the second and third cycles, the humus increment due to the organic and mineral fertilizers decreased by 2–3 times.     

Assessment and forecast of soil formation under irrigation in the steppe zone of Ukraine

Simulation of changes in energy costs of soil formation during the period of irrigation reclamation in the steppe zone has been performed using Wavelets analysis. A method has been proposed for the evaluation of natural-anthropogenic soil-forming process with consideration for the contribution of irrigation water to the hydrothermal regime during the growing season and the prediction of soil evolution under the effect of changing climatic conditions for the area of irrigated agriculture.     

Evolutionary trends in the geochemistry of steppe soils under long-term agricultural use

The aim of this research was to identify long-term changes in the material composition of arable and fallow lands in the agricultural district of an ancient center in the Northern Black Sea region. Geochemical features of changes in the upper mineral soil horizon of different-aged arable and fallow lands near the ancient city of Kerkinitis were studied. The multitemporal boundary between arable lands of different ages was identified, and indicators to diagnose residual signs of former agricultural loads were revealed in the material composition of agrozems using geostatistical methods. The use of such unique objects of study as soils of ancient agricultural areas is related to the potential evaluation of risks of fertility loss because of slow but practically irreversible processes of pedogenesis and the opportunity to prevent or reduce their negative manifestations in arable land.     

几种络合剂对土壤铁铝键结合腐殖质提取效果的比较研究

选用了０．５ｍｏｌ／ＬＮＨ４Ｆ,０．２５ｍｏｌ／ＬＥＤＴＡ和０．２５ｍｏｌ／ＬＮａ２Ｃ２Ｏ４三种络合剂在不同ｐＨ条件下对红壤、赤红壤和砖红壤中的腐殖质进行了溶解比较试验．结果表明：各浸提剂对铝的浸提能力为ＮＨ４Ｆ＞ＥＤＴＡ和Ｎａ２Ｃ２Ｏ４（ｐＨ≤８）,对铁的浸提能力则为ＥＤＴＡ＞Ｎａ２Ｃ２Ｏ４＞ＮＨ４Ｆ;各浸提剂在不同ｐＨ条件下,铁、铝及有机Ｃ（或Ｎ）的浸出量均为赤红壤＞砖红壤＞红壤。浸提剂的ｐＨ升高使有机Ｃ（或Ｎ）的浸提量增加,铁和铝的浸出量则不仅与络合剂对它的络合能力有关,而且还与溶液中ＯＨ－数量有较大关系。ｐＨ８左右的０．５ｍｏｌ／ＬＮＨ４Ｆ能较好地浸提出土壤中铝键结合腐殖质,且对铁键结合腐殖质破坏极小,它可能是一种区分土壤铁键结合和铝键结合腐殖质的较好溶剂。     

Physicochemical properties and dynamics of humus content in leached chernozem during long application of fertilizers

The effect of long application of fertilizers in crop rotation on the physicochemical properties of leached chernozem and dynamics of the humus content in it is established.     

Use of protective-stimulating compositions when growing wheat in Bashkortostan steppe zones

In the arid steppe zones of Bashkortostan, a substantial reduction of the level of development of harmful objects in spring wheat crops is achieved by means of the integrated use of biofertilizers, trace elements, biopreparations, antistress growth regulators and multifunctional pesticides, which allows improving the phytosanitary state of crops and increasing grain yield and quality.     

Phosphate content in virgin and arable soils of Western Transbaikalia

It is established that the virgin and arable soils of Western Transbaikalia have a high natural supply of total phosphorus, of which more than 30% is in the form of organic compounds. Mineral phosphates in these soils are represented mainly by highly basic calcium phosphates of the apatite type.     

Dynamics of agrophysical properties and humus content in chernozem under the moldboard, chisel and surface systems of basic soil tillage

Standard and ecologically correct agronomy system of corn based of modern soil processing devices studied. The influence of different soil processing on agrophysical properties and humus content of chernozem common revealed.     

Use of hyperspectral data to assess the effects of different nitrogen applications on a potato crop

This study was conducted to explore whether hyperspectral data could be used to discriminate between the effects of different rates of nitrogen application to a potato crop. The field experiment was carried out in the Central Potato Research Station, Jalandhar, on seven plots with different nitrogen (N) treatments. Spectral reflectance was measured using a 512-channel spectroradiometer with a range of 395–1075 nm on two different dates during crop growth. An optimum number of bands were selected from this range based on band–band r ², principal component analysis and discriminant analysis. The four bands that could discriminate between the rates of N applied were 560, 650, 730, and 760 nm. An ANOVA analysis of several narrow-band indices calculated from the reflectance values showed the indices that were able to differentiate best between the different rates of N application. These were reflectance ratio at the red edge (R_740/720) and the structure insensitive pigment index (SIPI). To estimate leaf N, reflectance ratios were determined for each band combination and were evaluated for their correlation with the leaf N content. A regression model for N estimation was obtained using the reflectance ratio indices at 750 and 710 nm wavelengths (F-ratio = 32 and r ² = 0.551, P < 0.000).     

重庆土壤铅含量污染评价及其影响因素分析

对重庆市8个区县160个表层土壤样品进行铅（Pb）含量分析,探讨土壤Pb含量特点及其影响因素,并运用地积累指数法对各区县表层土壤Pb污染作出评价。结果表明：全部供试土壤样品的Pb浓度几何平均值为37．30mg／kg,显著高于重庆市土壤Pb背景值（22．20mg／kg）,表现出一定的积累趋势。pH值是影响土壤全Pb含量的重要因素,当pH≤6．5和pH≥7．5时,随着pH值的增大,土壤全Pb含量增加;而6．5〈pH〈7．5时,随着pH值的增大,土壤全Pb含量减少。在供试样品有机质含量范围内,随着有机质含量的增加,土壤全Pb含量呈线性增加。总体上看,重庆市8个区县表层土壤Pb污染为轻度至中度,其中秀山县Pb污染最严重,达到中度污染水平。     

部分水稻土养分变化趋势的抽样调查

测定90个水稻土样点的有机质、全氮、全磷及速效磷、全钾及速效钾含量,求得各养分指标的平均数及不同等级样本所占的百分比与浙江省第2次土壤普查资料比较,结果发现水稻土有机质含量平均水平比20年前略有增加,变异程度有所增大;全氮含量较20年前有所提高,特别是＞2.00g/kg的土壤比20年前增加17.0个百分点;磷素含量增加最为突出,全磷平均由20年前的0.48g/kg提高到0.70g/kg,速效磷含量从6 mg/kg提高到39 mg/kg.速效磷含量＞20.0 mg/kg的水稻土比20年前增加25.2个百分点;全钾含量出现下降趋势,速效钾含量总体变化不大,虽然速效钾含量＜50.0 mg/kg的严重缺钾水稻土比20年前减少17.6个百分点,但速效钾含量50.1～100.0 mg/kg的水稻土却增加13.3个百分点.     

Heavy metal content in soils of suburban areas of the city of Chusovoi

The content of heavy metals in soils of garden plots in the city of Chusovoi exceeds the maximum allowable content in agrozems of the second bottom of the Chusovaya River. The method of measuring the specific magnetic susceptibility of soils allows, with a high probability, revealing territories polluted with Ni, Cu, Zn, Cr, and Mn.     

泰来县耕地土壤硒含量特征及空间分布

为研究耕地中土壤硒的含量特征及空间分布,选取黑龙江省产粮大县泰来县为研究区,以多目标区域地球化学调查成果为数据基础,采用多元统计、地统计和普通克里格插值等方法分析泰来县耕地土壤硒元素含量及其空间分布特征。研究表明:1)泰来县耕地表、深层土壤硒含量均值分别为0.155和0.056mg/kg,都低于黑龙江省土壤背景值,水田硒元素含量均值在表、深层土壤中都高于旱地;2)土壤硒含量除受成土母质的影响外,还与土壤有机碳、总氮、Fe_2O_3与Al_2O_3含量以及pH等有关;3)表层土壤硒含量较高的区域主要分布在中部,根据土壤硒含量分布状况,富硒地区面积占耕地总面积的6.2%,研究区中部的六三一分厂、丰收村、六三良种场、河北村、六三二分厂、新建村、双山村、解放村和永发村等村耕地土壤硒含量较高,地累积指数表明土壤中生物毒性显著的重金属元素在研究区基本上不存在污染,可以在这些区域发展富硒农产品,以带动当地经济的发展。     

红枫湖水库消落区典型土壤养分与重金属含量调查

为了弄清红枫湖水库消落区土壤养分状况,以期为消落区土壤利用提供科学依据,以贵州最大的人工湖泊红枫湖水库消落区典型土壤为对象,调查了消落区土壤中的养分状况及重金属含量。调查结果表明,消落区调查点的典型土壤全量养分、速效养分不高,重金属含量也处于较低水平。在重视引导、适量利用、正确管理的原则指导下,土壤中的氮、磷、钾养分、重金属不会大量向水体迁移,不会对水库水源带来污染。     

广西耕地土壤铜的含量及其影响因素

对2242个采自广西不同类型的耕地表层土壤样品进行有效铜含量分析,结果表明,广西耕地土壤铜的含量比较丰富,全铜含量在1.03~101.18m g/kg之间,平均27.41m g/kg,高于全国和世界平均含量;有效铜含量在0.01~19.19m g/kg之间,平均2.48m g/kg,低于0.2m g/kg缺铜临界值的土壤只占样点的0.49%;成土母质、土壤有机质、土壤pH值和土壤的农业利用方式是影响土壤有效铜含量的主要因素。     

提取液对土壤有效重金属含量与生物有效性的影响

土壤污染已成全球性问题,发展中国家尤为严重。在土壤污染元素中,Cu、Zn、Pb的污染占很大比重,有效态污染元素对作物、动物及人体的毒害更为严重。重金属的有效态决定了生物有效性及对环境的危害程度,它是污染土壤治理和修复的基础。只有运用合宜的提取方法,准确地测定重金属的有效性,才能制定出有效的治理方案。通过5种提取液的比较得出,醋酸铵提取液、DTPA&TEA提取液、EDTA提取液等3种提取剂能较好地反映土壤重金属的生物有效性,适用于土壤重金属的生物有效性评价。     

Significance of individual components of organic matter in the formation of the water-stable structure of light gray forest soils of the northern forest steppe

The effect of humus, readily decomposable organic matter, and carbohydrates of a nonspecific nature on the formation of water-stable aggregates in field rotation members has been studied. It has been established that the degree of effect of organic matter on aggregation of particles is determined by the character of use of the plots and crop being grown.     

Use of Trichoderma spp. in remediation of polluted soils and waters

Trichoderma spp. probably have a role in remediation of polluted soils and waters. Highly rhizosphere competent strains persist on roots for an extended period of time (at least months) and continuously interact with the plants. They can increase general plant and root growth and increase uptake of a variety of materials. This makes the Trichoderma-plant interaction highly attractive for use in phytoextraction technologies. Moreover, Trichoderma spp. are resistant to a wide range of toxic…     

膨润土对镉污染土壤团聚体结构特征及有机碳含量的影响

通过4年田间原位钝化修复定位试验,研究施用膨润土钝化修复重金属镉污染菜地过程中,膨润土对土壤团聚体结构、稳定性以及有机碳含量变化特征。结果表明,与对照相比,施加膨润土后2～5 mm和5～8 mm粒径土壤团聚体数量增加,而2 mm的粒径团聚体数量则有所降低。投加膨润土提高了土壤团聚体稳定性,其几何平均直径(Geometric mean diameter, GMD)和平均质量直径(Mean weight diameter, MWD)分别增加9.57%～33.48%和4.74%～31.39%。与对照相比,全土和各粒径团聚体中有机碳含量随膨润土投加量增加而增加,而颗粒有机碳的含量则相反,最大降低了11.64%。投加膨润土提高了2～5 mm粒级团聚体对土壤有机碳含量的贡献率,0.5 mm粒级团聚体对土壤有机碳含量贡献率降低。投加膨润土后土壤烯烃类、烷烃类和酚类官能团含量有所增加,与对照相比,增加幅度分别为1.52%～4.55%、2.60%～36.28%和2.06%～10.98%。     

我国设施菜田土壤重金属含量特征与影响因素

为调查我国设施菜田土壤重金属污染状况,探讨种植年限、土壤有机碳及全氮等因素对设施菜田土壤重金属含量的影响,以我国设施菜田土壤为研究对象,通过文献查阅和土壤样品采集两种方式,在全国和黄淮海与环渤海设施蔬菜主产区,分别获取土壤401组/233组和548个/310个样本点数据,利用数理统计、相关性及多元统计分析等方法定量描述了我国设施菜田土壤重金属积累及污染特征,并进行了土壤重金属污染影响因素分析。结果分析表明:在全国范围内,文献资料中的设施菜田土壤Cd、Pb、As、Cr、Hg、Cu、Zn、Ni平均含量分别为0.32、24.9、8.45、83.6、0.05、29.9、70.7、27.4mg kg-1,超标率排序为Cd(30.5%)>Cu(9.8%)>C(r7.2%)>Zn(4.8%)>Pb(4.7%)>As(3.7%),在采集的设施菜田土壤样品中,八种重金属平均含量分别为0.13、21.9、6.48、41.9、0.09、23.6、72.1、21.4 mg kg-1,超标率排序为Cd(5.3%)>Cu(1.8%)>As(1.6%)>Zn(0.9%)>Pb(0.6%)>Cr(0.6%)。在黄淮海与环渤海设施蔬菜主产区,文献资料中的设施菜田土壤Cd、Pb、As、Cr、Hg、Cu、Zn、Ni平均含量分别为0.30、25.9、8.56、67.1、0.08、33.3、79.1、32.5 mg kg-1,超标率排序为Cd(25%)>Cu(10.4%)>C(r9.9%)>Pb(6.3%)>Zn(2.2%)>As(2.1%),在采集的设施菜田土壤样品中,八种重金属平均含量分别为0.13、22.8、5.93、43.5、0.08、23.1、69.3、19.4mg kg-1,超标率排序为Cd(3.1%)>Cu(2.1%)>Cr(2.0%)>As(1.2%)>Pb(0.6%)>Zn(0.5%)。而Hg、Ni基本都不超标。随种植时间的延长,设施菜田土壤中Cd、As、Cu、Zn含量呈逐步累积状态,文献来源的土壤Cd在种植21~25年(3.60mg kg-1),土壤Cu、Zn含量在26~30年(80.3mg kg-1和180mg kg-1)达到最高值;在采集的土壤样品中,Cd含量分别在种植16~20年(0.19mg kg-1)、As、Cu、Zn在21~25年(16.0、53.6mg kg-1和131mg kg-1)达到最高值。相关性分析表明,设施菜田土壤Cd含量与有机碳呈显著正相关,Cu、Zn含量与有机碳、全氮、速效磷、速效钾呈显著正相关,结合肥料中重金属含量进一步验证了磷肥和粪肥投入是设施菜田土壤重金属的重要来源。因此,为保证土壤环境及蔬菜质量安全,应注重肥料等污染源的控制。