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1.
The relationships between climate changes and the soil cover are analyzed. The greenhouse effect induced by the rising concentrations of CO2, CH4, N2O, and many other trace gases in the air has been one of the main factors of the global climate warming in the past 30–40 years. The response of soils to climate changes is considered by the example of factual data on soil evolution in the dry steppe zone of Russia. Probable changes in the carbon cycle under the impact of rising CO2 concentrations are discussed. It is argued that this rise may have an effect of an atmospheric fertilizer and lead to a higher productivity of vegetation, additional input of organic residues into the soils, and activation of soil microflora. Soil temperature and water regimes, composition of soil gases, soil biotic parameters, and other dynamic soil characteristics are most sensitive to climate changes. For the territory of Russia, in which permafrost occupies more than 50% of the territory, the response of this highly sensitive natural phenomenon to climate changes is particularly important. Long-term data on soil temperatures at a depth of 40 cm are analyzed for four large regions of Russia. In all of them, except for the eastern sector of Russian Arctic, a stable trend toward the rise in the mean annual soil temperature. In the eastern sector (the Verkhoyansk weather station), the soil temperature remains stable.  相似文献   

2.
寿光大棚菜地土壤呼吸强度、酶活性、pH与EC的变化研究   总被引:4,自引:1,他引:3  
为防治土壤退化、促进农业可持续发展提供科学依据,以寿光地区露地土壤作对照,研究了连作1、5、8和12年大棚蔬菜(番茄)土壤有关生物学指标的变化。结果表明,土壤呼吸强度和脱氢酶活性棚内高于棚外,并随连作年限延长开始增强而后减弱,由于管理差异,12年棚龄土壤又回升。随着连作年限延长,土壤脲酶活性逐渐减弱,而过氧化氢酶活性逐渐增强;土壤呼吸强度和酶活性都由表层向底层逐渐减弱。土壤pH随连作年限增加逐渐下降,而EC逐渐增加,至12年棚龄时,与对照比0—20 cm土层pH下降了1.06单位,其他层次变化不显著。试验还表明,该地区表层土壤pH变化于6.45~7.51,EC 0.5 mS/cm,能较好地满足作物生长需要,同时,EC是影响土壤pH及酶活性变化的重要因素。土壤EC及过氧化氢酶活性可作为反映大棚菜地土壤质量变化的参考指标。  相似文献   

3.
The analysis of modern Russian legislation in the sphere of environmental protection, management of natural resources, soil conservation, and land cadaster works has been performed. It is shown that a common federal approach to environmental impact assessments and soil quality assessments is virtually absent. Ecological indices are not taken into account in the federal land cadaster. Most of the recently adopted legislative regulations in this sphere have a technocratic character. The recent governmental regulations on land and environmental monitoring have still not been put into practice. To ensure soil conservation policy and protect soils as a component of the environment, a distinction should be made between the notions of soil and land in the legal documents. The basic principles of the proposed law “On Soil Conservation” are outlined. It is argued that a system of soil-ecological criteria should be elaborated for the proper assessment of soil quality. As a soil conservation service is absent in Russia, it is suggested that the Dokuchaev Soil Science Society should organize an association for the protection and rehabilitation of Russian soils.  相似文献   

4.
The need for the All-Russia soil-geographic database satisfying international standards is substantiated. Soil functions and the role of soils as a natural resource are analyzed. The soil resources of Russia are briefly described, and the problem of soil degradation is discussed. It is shown that the Russian legislative base regulating soil management and soil conservation policies is in a very poor state and requires improvement. The world policy of soil conservation is compared with the situation in Russia. The procedure for creating the State Soil-Geographic Database of the Russian Federation is described. It is supposed that it will consist of three major directions: the creation of a geographic database on a scale of 1: 2.5 M, the creation of a database of soil profiles, and the creation of a generalized database of the factors of soil formation and morphogenetic soil features. In addition, information about the economic use of typological soil units distinguished on the Soil Map of Russia on a scale of 1: 2.5 M (2007) will be aggregated.  相似文献   

5.
朱一  李晓龙  吴喆  陶岳  王雅杰  孙宇  张小凯  王震宇 《土壤》2023,55(2):234-244
土壤生态系统是温室气体排放的主要来源之一,降低土壤温室气体排放对于缓解全球变暖具有重要意义。近年来,生物质炭在改良土壤性质、提高土壤碳汇和影响土壤温室气体排放方面展现出了巨大的潜力。因此,关于施加生物质炭对土壤温室气体排放影响的研究已经成为了环境科学和农业生态领域的研究热点。然而,生物质炭对土壤温室气体净排放的影响是促进还是抑制尚无统一定论。不同植被类型条件下土壤温室气体排放也存在较大差异,故而研究添加生物质炭对不同植被类型土壤温室气体排放的影响至关重要。本文综述了添加生物质炭对林地、农田及设施蔬菜土壤中CO2、CH4和N2O排放的影响,探讨了生物质炭对土壤温室气体排放的作用机制。总结发现,不同植被类型土壤添加生物质炭将降低土壤N2O的排放,并且增加土地对CH4的吸收,而对CO2排放的影响没有统一定论。结合国内外生物质炭在该领域的研究现状,未来需开展生物质炭在土壤温室气体减排领域的长期系统研究,同时应充分考虑使用生物质炭可能存在的潜在环境风险,以期为生物质炭在土壤温室气体减排中的应用提供可靠的科学依...  相似文献   

6.
不同栽培方式菜田耕层土壤重金属状况   总被引:6,自引:2,他引:4  
【目的】评价不同栽培方式(温室、大棚和露地)菜田土壤重金属状况,为菜田土壤质量改善和蔬菜高效安全施肥提供一定的理论依据。【方法】针对我国北方3个区域(东北、黄淮海、西北地区)和南方4个区域(华中、西南、华东、华南地区)主要蔬菜种植区不同栽培方式的典型菜田耕层土壤展开调查,选择的主要菜区不同栽培方式的菜田均为远离城郊的未受到工业“三废”、汽车尾气等污染的农村菜田,取样时间是2013年作物收获后或蔬菜施肥前或生长后期,共采集503个土壤样品,对温室、大棚和露地三种栽培方式下土壤重金属状况进行了研究。【结果】1)采样区设施(温室和大棚)菜田土壤重金属Cu、Zn和Cd总量总体上均高于露地菜田土壤,较露地菜田土壤平均分别高12.2%、21.7%和30.4%。2)随着种菜年限的增加,菜田土壤重金属Cu、Zn和Cd总量呈显著增加的趋势。不同栽培方式菜田土壤中均可能存在几种重金属同时污染的复合污染现象,土壤Cu、Zn、Cd等之间的相关性均达到极显著水平。3)采样区不同栽培方式菜田土壤Cd的二级超标率在19.2%~22.3%之间,温室、大棚和露地菜田土壤Cd的单项污染指数平均分别为0.97、0.98和0.70;土壤Cu、Zn、Pb、Cr、As和Hg的二级超标率在0~14.6%之间,单项污染指数在0.06~0.52之间。【结论】设施菜田N、P2O5和K2O总量及有机肥用量均显著高于露地菜田,可能是造成设施菜田土壤中重金属Cu、Zn和Cd积累显著高于露地菜田的重要原因。采样区设施(温室和大棚)菜田土壤Cd总体上处于污染警戒级状态,露地菜田土壤总体上未受到Cd的污染;设施和露地菜田土壤Cu、Zn、Pb、Cr、As和Hg总体上均未构成对土壤的污染。  相似文献   

7.
为探讨影响土壤释放CO2 潜力的因素, 本研究采集黄土丘陵区3 种典型土地利用方式下(苹果园、退牧草地、辽东栎林地)的原状土壤样品, 室内进行不同温度和水分梯度的培养试验, 测定培养过程中土壤释放CO2 的速率以及土壤的理化性质, 并分析其对土壤释放CO2 潜力的影响。结果表明: 影响土壤释放CO2 速率的主要因素是温度, 指数模型Ra=aebT 可以很好地预测土壤呼吸速率随温度的变化情况。含水率对土壤呼吸速率影响不大, 但含水率对Q10 值的影响明显, 较高或较低的水分情况下都会降低土壤呼吸速率随温度变化的敏感程度。3 种土地利用方式下, 土壤释放CO2 的速率表现为: 林地土壤>草地土壤>果园土壤。土壤理化性质中, 有机碳对土壤呼吸的影响最大, 其次为有机氮; 此外微生物量碳很可能是间接影响土壤CO2 释放速率的一个因素。  相似文献   

8.
In this paper we describe the accumulation of soil organic matter (SOM) during pedogenesis and the processes that can lead to the emission of greenhouse gases (CO2, CH4, N2O) to the atmosphere via SOM decomposition and denitrification. We discuss the role of management on SOM accumulation and loss, and the potential for controlling emission or comsumption of greenhouse gases by soils. We conclude that under current climate conditions there are global scale opportunities to reduce greenhouse gas emissions from soils and increase the indirect sequestration of greenhouse gases in soils through improved soil management.  相似文献   

9.
The roots of soil micromorphology in Russia are inseparably connected with mineralogical studies. The development of soil micromorphology as a specific field of soil science was greatly affected by the works of W. Kubiena and R. Brewer. In the 1970s, centers for micromorphological studies appeared in many research and educational organizations. They gathered a wealth of information on the micromorphology of different soil types in the Soviet Union. The major tendencies in the development of soil micromorphology and its practical applications are considered: from the general problems of the genesis of modern soils and paleosols and methodological grounds of soil micromorphology to the diagnostics of anthropogenic changes of soils on the basis of data on their microfabric with quantitative assessments of soil morphology at different levels (from the macrolevel to the micro- and submicrolevels). Data on the contribution of Russian micro- morphologists to the study of certain soils and on the major scientific events and organizational efforts in this field are also considered.  相似文献   

10.
试验设对照、尿素、尿素+草甘膦和尿素+丁草胺4个处理,尿素氮用量为200mg·kg-1干土,除草剂用量为10mg有效成分·kg-1干土。在实验室恒温培养条件下,研究除草剂对菜田土壤温室气体排放的影响。结果表明,菜田土壤中施用氮肥显著增加了温室气体N2O、CO2和CH4的排放。尿素氮肥中添加草甘膦显著抑制N2O、CO2的排放,分别比尿素处理降低48.4%和20.2%;添加丁草胺显著抑制N2O排放,比尿素处理降低23.2%,对CO2排放略有减少但不显著;草甘膦和丁草胺对CH4排放都无明显影响。这说明除草剂对土壤温室气体的排放具有显著影响,但不同除草剂品种的效应也存在明显差异。因此,在农田温室气体排放估算时应考虑除草剂的施用对温室气体减排所产生的效果。  相似文献   

11.
Consequent to the interest in converting degraded lands for cultivation of biofuel crops, concerns have been expressed about greenhouse gas (GHG) emissions resulting from changes in soil‐carbon (C) stock following land conversions. A literature‐based study was undertaken for estimating the magnitude of emission of GHGs, particularly carbon dioxide (CO2), following an assessment of the extent and causes of land degradation and the nature of CO2 emission from soils. The study estimated the potential for CO2 emission resulting from changes in soil‐carbon stock following land conversions, using oil palm (Elaeis guineensis Jacq.) as a case study. The analysis indicated that, overall, the magnitude of CO2 emission resulting from changes in soil C stock per se following opening up of degraded land would be low compared with other potential sources of CO2 emission. However, lack of data on critical aspects such as baseline soil C status was a limitation of the study. Soil respiration is the single best measure of GHG emission from soils. Fixation of C in additional biomass will compensate, over time, for C loss through soil respiration following a change in land use or land management, unless such changes involve conversion of existing large C stocks. Therefore, any net CO2 emission from soils resulting from changes in soil C stock following opening up of degraded land is likely to be a short‐term phenomenon. The estimations used in the study are based on various assumptions, which need to be validated by experimental field data. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

12.
Systems of the vertical soil zonality in mountains of Russia have been analyzed on the basis of the Soil Map of the Russian Federation on a 1: 2.5 M scale. Types of the vertical soil zonality are classified into classes, subclasses, and groups. Overall, 4 classes, 8 subclasses, and 27 types of the vertical zonality are distinguished. The soil-geographic zoning of mountain systems of Russia is developed, and provinces and districts of mountainous soils are separated with respect to the character of the vertical soil zonality. The geographic regularities of their distribution are discussed.  相似文献   

13.
Tillage and agricultural sustainability   总被引:1,自引:0,他引:1  
Agricultural sustainability implies an increasing trend in per capita productivity to meet the present needs without jeopardizing the future potential. Soil tillage, soil surface management to alleviate soil-related constraints to crop production, is a basic and an important input with short- and long-term effects on sustainability. An important effect of soil tillage on sustainability is through its impact on the environment e.g. soil degradation, water quality, emission of greenhouse gases from soil-related processes, etc. The need to attain agricultural sustainability is particularly urgent in several tropical eco-regions and soils of low-carrying capacity in the tropics.

Soil tillage influences atricultural sustainability through its effects on soil processes, soil properties, and crop growth. However, there is no one blueprint of a universally applicable sustainable tillage system. Appropriate tillage systems are soil- and crop-specific and their adaptation is governed by both biophysical and socio-economic factors. In addition to increasing crop yields, tillage methods must also facilitate soil and water conservation, improve root system development, maintain a favorable level of soil organic matter content, and reverse degradative in the soil's life-support processes.

Important components or sub-systems of conservation-effective tillage systems include mulch farming, no-till or reduced tillage systems, use of cover crops and planted fallows, agroforestry, raised beds or ridge-tillage, and soil inversion or deep plowing. The ecological limits for the applicability of these components or sub-systems differ widely. The efforts of a multi-disciplinary team (comprising soil scientists, agricultural engineers, agronomists, economists and social scientists) are needed to develop site-specific tillage methods to achieve both short- and long-term goals of agricultural sustainability.  相似文献   


14.
Abstract

As a means of economic disposal and to reduce need for chemical fertilizer, waste generated from swine production is often applied to agricultural land. However, there remain many environmental concerns about this practice. Two such concerns, contribution to the greenhouse effect and stratospheric ozone depletion by gases emitted from waste‐amended soils, have not been thoroughly investigated. An intact core study at Auburn University (32 36′N, 85 36′W) was conducted to determine the source‐sink relationship of three greenhouse gases in three Alabama soils (Black Belt, Coastal Plain, and Appalachian Plateau regions) amended with swine waste effluent. Soil cores were arranged in a completely random design, and treatments used for each soil type consisted of a control, a swine effluent amendment (112 kg N ha?1), and an ammonium nitrate (NH4NO3) fertilizer amendment (112 kg N ha?1). During a 2‐year period, a closed‐chamber technique was used to determine rates of emission of nitrous oxide (N2O)–nitrogen (N), carbon dioxide (CO2)–carbon (C), and methane (CH4)–C from the soil surface. Gas probes inserted into the soil cores were used to determine concentrations of N2O‐N and CO2‐C from depths of 5, 15, and 25 cm. Soil water was collected from each depth using microlysimeters at the time of gas collection to determine soil‐solution N status. Application of swine effluent had an immediate effect on emissions of N2O‐N, CO2‐C, and CH4‐C from all soil textures. However, greatest cumulative emissions and highest peak rates of emission of all three trace gases, directly following effluent applications, were most commonly observed from sandier textured Coastal Plain and Appalachian Plateau soils, as compared to heavier textured Black Belt soil. When considering greenhouse gas emission potential, soil type should be a determining factor for selection of swine effluent waste disposal sites in Alabama.  相似文献   

15.
The first in the world collection of soil monoliths from the Dokuchaev Central Soil Museum (St. Petersburg) was examined in order to test and verify the new substantive-genetic classification system of Russian soils. This work made it possible to introduce a number of refinements in the second edition of the Russian soil classification system (2004). These refinements included the addition of new diagnostic horizons and features and the specification of their definitions. The analysis of the museum collection of soils has definite advantages, as it allows one to work with soils from different geographic regions simultaneously, to consider morphological features of soils under standard conditions, to use analytical soil data, and to analyze different names (i.e., interpretations of the genesis) given to the same soils. At the same time, a critical analysis of the collection creates necessary prerequisites for a comparative analysis of soils from different regions of Russia with the national reference soil base, which is important in order to reveal the real pedogenetic diversity and improve the information base on soil resources in Russia.  相似文献   

16.
在滇池流域农田,重点是滇池滨湖区和入滇河流柴河流域,选择不同土地利用类型、不同种植年限大棚采集土壤样品进行气相色谱(ECD)分析。结果表明,试区土壤中有机氯农药(OCPS)检出率为95.9%,OCPS的残留量范围、平均值分别为nd-63.4 μg·kg-1、6.3 μg·kg-1,以p,p′-DDE为主要残留物,98.3%的样点达到国家《土壤环境质量标准》一级标准(〈50 μg·kg-1)。与国内同类报道相比,滇池周边土壤中OCPS的残留较低。不同土地利用类型有机氯残留量排序为:设施栽培〉水稻田〉露天菜地〉荒草地〉坡耕地;不同大棚种植年限土壤中,棚龄长于15 a的 OCPS残留量要明显高于棚龄短于15 a的,而棚龄短于15 a的,土壤中OCPS含量差异不明显。  相似文献   

17.

Purpose  

Land use type is an important factor influencing greenhouse gas emissions from soils, but the mechanisms involved in affecting potential greenhouse gas (GHG) emissions in different land use systems are poorly understood. Since the northern regions of Canada and China are characterized by cool growing seasons, GHG emissions under low temperatures are important for our understanding of how soil temperature affects soil C and N turnover processes and associated greenhouse gas emissions in cool temperate regions. Therefore, we investigated the effects of temperature on the emission of N2O, CO2, and CH4 from typical forest and grassland soils from China and Canada.  相似文献   

18.
The first inventory and zoning of the emission and sink of methane and carbon dioxide in the urban structure of greenhouse gases from soils and surface technogenic formations (STFs) (Technosols) on technogenic, recrementogenic, and natural sediments have been performed with consideration for the global warming potential under conditions of different formation rate of these gases, underflooding, and sealing. From gas geochemical criteria and anthropogenic pedogenesis features, the main sources of greenhouse gases, their intensity, and mass emission were revealed. The mass fractions of emissions from the sectors of waste and land use in the inventories of greenhouse gas emissions have been determined. New sources of gas emission have been revealed in the first sector, the emissions from which add tens of percent to the literature and state reports. In the second sector, emissions exceed the available data in 70 times. Estimation criteria based on the degree of manifestation and chemical composition of soil-geochemical anomalies and barrier capacities have been proposed. The sink of greenhouse gases from the atmosphere and the internal (latent) sink of methane in soils and STFs have been determined. Ecological functions of soils and STFs have been shown, and the share of latent methane sink has been calculated. The bacterial oxidation of methane in soils and STFs exceeds its emission to the atmosphere in almost hundred times.  相似文献   

19.
Tropical acid peat land could be an emission source of greenhouse gases, especially, of methane, because peat soil contains large amount of carbon. When these acid peat lands are utilized for farming, adjustment of the acid condition by adding lime (CaCO3) becomes essential. However, by adding lime to these soils, methane and carbon dioxide production potentials were increased in various acid peat soils. Soluble organic carbon also increased in soils by the lime addition. It was due to that the soil pH rose by liming and the decomposition of organic matter was enhanced under these conditions.  相似文献   

20.
Intensive greenhouse vegetable‐production systems commonly utilize excessive fertilizer inputs that are inconsistent with sustainable production and may affect soil quality. Soil samples were collected from 15 commercial greenhouses used for tomato production and from neighboring fields used for wheat cropping to determine the effects of intensive vegetable cultivation on soil microbial biomass and community structure. Soil total nitrogen (N) and organic‐matter contents were greater in the intensive greenhouse tomato soils than the open‐field wheat soils. Soil microbial carbon (C) contents were greater in the greenhouse soils, and soil microbial biomass N showed a similar trend but with high variation. The two cropping systems were not significantly different. Soil microbial biomass C was significantly correlated with both soil total N and soil organic matter, but the relationships among soil microbial biomass N, soil total N, and organic‐matter content were not significant. The Biolog substrate utilization potential of the soil microbial communities showed that greenhouse soils were significantly higher (by 14%) than wheat soils. Principal component (PC) analysis of soil microbial communities showed that the wheat sites were significantly correlated with PC1, whereas the greenhouse soils were variable. The results indicate that changes in soil microbiological properties may be useful indicators for the evaluation of soil degradation in intensive agricultural systems.  相似文献   

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