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Temporal changes of eroded soils depending on their agricultural use in the southern Cis-Ural region
I. M. Gabbasova R. R. Suleimanov I. K. Khabirov M. A. Komissarov M. Fruehauf P. Liebelt T. T. Garipov L. V. Sidorova F. Kh. Khaziev 《Eurasian Soil Science》2016,49(10):1204-1210
Temporal changes of eroded soils in the southern Cis-Ural region (Republic of Bashkortostan) depending on their agricultural use during the period from 1975 to 2011 were studied. In the northern foreststeppe zone, the development of erosion processes was retarded upon the use of soil-saving management practices and grain-fallow-grass crop rotations. In slightly eroded light gray forest soils (Eutric Retisols (Cutanic)), the thickness of humus-accumulative horizons and the content of humus increased; the conversion of cropland into permanent fallow was found to be the most efficient measure to control soil erosion. In podzolized chernozems (Luvic Greyzemic Chernic Phaeozems) and typical chernozems (Haplic Chernozems) of the Cis-Ural steppe, the content of humus in the plow layer under grain-row crop rotation and classical soil management decreased, especially in moderately eroded soils. The development of water and wind erosion on slopes depended on the slope shape: the texture of soils at different degrees of erosion on slopes with free runoff became coarser by one gradation after 35 years; in the presence of linear obstacles in the lower part of slopes, the content of fine fractions in moderately and strongly eroded soils increased. 相似文献
3.
横、顺坡垄作对黑土坡面侵蚀-沉积周期规律的影响 总被引：3，自引：0，他引：3
我国东北黑土区的水土流失和土地退化正严重制约着东北地区农业经济发展,威胁国家粮食生产安全。掌握不同垄作方向耕作措施下的东北黑土区土壤侵蚀规律,对合理布设水保措施、控制水土流失等具有重要意义。采用137Cs示踪技术并结合小波分析方法,对不同垄作方向坡耕地土壤侵蚀-沉积速率的空间变化规律开展研究。结果表明：(1)横、顺坡垄作坡面137Cs平均浓度分别为1 802 Bq·m-2和1 770 Bq·m-2,均小于当地背景值2 417 Bq·m-2,说明在两种垄作方向下均发生了不同程度的土壤侵蚀。(2)横坡垄作的坡面平均侵蚀速率(1 341 t·km-2·a-1)小于顺坡垄作(1 477 t·km-2·a-1),表明在长期平均条件下前者的水土保持作用优于后者。尽管研究区土壤侵蚀属于轻度侵蚀,但其侵蚀速率远大于黑土区的土壤容许流失量(200 t·km-2·a-1 相似文献
4.
华南兴国县影响土壤侵蚀时空动力学的环境因素 总被引：7，自引：0，他引：7
WANG Ku SHI Xue-Zheng YU Dong-Sheng SHI De-Ming CHEN Jing-Ming XU Bin-Bin LIANG Yin LI De-Cheng 《土壤圈》2005,15(5):620-627
By using soil erosion maps of four different time periods and a digital elevation model (DEM), in combination with the remote sensing and GIS technologies, soil erosion dynamics in Xingguo County of Jiangxi Province in South China were analyzed on both temporal and spatial scales in soils of different parent materials, altitudes and slopes. The results showed that from 1958 to 2000 severe soil erosion was coming under control with a decreasing percentage of the land under severe erosion. It was also found that the soils developed from Quaternary red clay, granite and purple shale were more susceptible to soil erosion and that areas sitting between 200 to 500 m in altitude with a slope less than 3° or between 7° to 20° where human activities were frequent remained to be zones where soil erosion was most likely to occur. These areas deserve special attention in monitoring and controlling. 相似文献
5.
Changing role of cultivated land in the global carbon cycle 总被引：3，自引：0，他引：3
The carbon balance is ill defined for agricultural lands so that their role in global C balance cannot be accurately estimated.
Changes in agriculture in the last 50 years have resulted in a general increase in grain yields, total net annual production
(TNAP), and C input to the soil. Amounts of C returned annually with crop residues on Sanborn Field, one of the oldest experimental
fields in the United States, increased after 1950, and this was accompanied by C accumulation in soils. Under wheat monocrop
(with mineral fertilizer), C accumulated at a rate of 50 g m–2 year–1. A 3-year rotation (corn/wheat/clover) with manure and nitrogen applications sequestered 150 g m–2 year–1 of C. Total C balance for the wheat and corn production area in the United States, approximated on the basis of these rates,
indicates that at least 32 Tg C was sequestered annually during the last 40–50 years.
Received: 1 December 1997 相似文献
6.
Yu. G. Chendev A. L. Aleksandrovskii O. S. Khokhlova L. G. Smirnova L. L. Novykh A. V. Dolgikh 《Eurasian Soil Science》2011,44(1):1-12
A sequence of dark gray forest soils developing under a virgin broadleaved forest and under croplands used for 100 and 150
years was studied in the southern part of the forest-steppe zone on the Central Russian Upland. The application of multiple
study methods for these objects made it possible to trace the evolutionary changes in the soil properties during the 150-year-long
period of regular plowing. Several important trends in the soil development under the impact of the cultivation were revealed:
(a) an increase in the thickness of the humus layer (according to the measurements at 20 points for each of the objects),
(b) an increase in the amount of mole tunnels, (c) a decrease in the coefficient of the textural differentiation of the soil
profile (with respect to the clay content), (d) an increase in the contents and reserves of the major nutrients upon a stable
pool of humus in the upper meter, and (e) some alkalization and carbonization of the profile. Powdery accumulations of carbonates
and whitish calcareous coatings on the faces of prismatic peds appeared at a depth of more than 130 cm. The plowed soils contained
thin deep fissures, the surface of which was covered by dark-colored clayey-humus coatings at the depth of 50–110 cm. The
radiocarbon age of the humus in these coatings was 500–1000 years younger than the age of the humus in the soil mass between
the fissures. This set of features attests to the evolution of the plowed dark gray forest soils into chernozems under the
impact of plowing. 相似文献
7.
We investigated whether, under a temperate climate and in a maize crop, earthworm casts could contribute to soil erosion
and further favour the exportation of phosphorus by runoff waters. Recording of casts was made in compacted (wheel-tracks)
and non-compacted inter-rows, for a 2-month period in spring. To assess the rainfall impact on cast evolution, half of the
observation sites were protected against rain splash by a nylon mesh placed above the soil surface. The water runoff was collected
and analysed for sediment contents and phosphorus concentration. The mean annual production of surface casts was calculated
to be 34 kg (dry weight) year–1 kg–1 earthworm (fresh weight). Synchronization between cast erosion and rainfall events was shown under natural conditions (unprotected
sites). The erosion rate was 4 times greater over rainy periods than dry ones, reaching 80% of cast numbers. It appeared that
not the runoff effect but the splash effect, due to the kinetics of the drops, disrupted casts. Newly formed casts disappeared
first, with the erosion rate decreasing twofold for casts more than 10 days old. Cast erosion and runoff, as well as worm
casting activity, were greater under compacted sites than under non-compacted sites, indicating an influence of earthworms
on soil erosion from compacted soils. The total phosphorus content was similar in casts and uningested soil (0.80 mg phosphorus
g–1). Potential phosphorus losses from cast erosion was calculated to reach 25–49 mg phosphorus m–2 per rainfall event depending on soil compaction. The amounts of particulate phosphorus recovered in water runoff after each
rainfall event varied from 1 mg to 11 mg phosphorus. These results are compared and discussed.
Received: 20 October 1998 相似文献
8.
Yu. N. Vodyanitskii I. O. Plekhanova E. V. Prokopovich A. T. Savichev 《Eurasian Soil Science》2011,44(2):217-226
The upper soil horizons are strongly contaminated in the area influenced by the Mid-Urals copper smelter. In the technogenic
desert and impact zones, the contents of a number of elements (Cu, Zn, As, Pb, P, and S) by many times exceed their clarke
values and the maximum permissible concentrations (or provisional permissible concentrations). The degree of technogeneity
(Tg) for these elements is very high in these zones. In the far buffer zone, Tg is about zero for many elements and increases
up to Tg = 27–42% for four heavy elements (Cu, Zn, Pb, and As) and up to 81–98% for P and S. The buffer capacity of the humus
horizon depends on the soil’s location within the technogeochemical anomaly and also on the particular pollutant. In the impact
zone, it is equal to 70–77% for lead and arsenic, although other technogenic elements (Zn, Cr, S, and P) are poorly retained
and readily migrate into the deeper horizons (the buffer capacity is equal to 14–25%). Nearly all the heavy metals enter the
soil in the form of sulfides. The soils in the area affected by the Noril’sk mining and smelting metallurgical enterprise
are subdivided into two groups according to the degree of their contamination, i.e., the soils within Noril’sk proper and
the soils in its suburbs to a distance of 4–15 km. The strongest soil contamination is recorded in the city: the clarke values
are exceeded by 287, 78, 16, 4.1, and 3.5 times for Cu, Ni, Cr, Fe, and S, respectively. The major pollutants enter the soil
from the ferruginous slag. The soil’s contamination degree is lower in the suburbs, where heavy metal sulfides reach the soils
with the aerial emission from the enterprise. 相似文献
9.
A. N. Gennadiev A. P. Zhidkin K. R. Olson V. L. Kachinskii 《Eurasian Soil Science》2010,43(9):1047-1054
A new method of magnetic tracer was applied by the authors for a quantitative assessment of erosional processes. The rates
of erosion were determined for cultivated and virgin soils (predominantly, chernozems) on slopes in different parts of the
United States and Russia. Quantitative parameters of soil loss and soil deposition for the slopes of different shapes and
aspects were found. Specific features of erosional processes within different parts of slopes were revealed. The relationships
between the intensity of erosion and the humus state of the soils were characterized, and the effect of land use on the rates
of soil erosion was estimated. 相似文献
10.
A typification of soil catenas on slopes from the manifestations of soil erosion and accumulation processes studied at several
key plots in the central part of the East European Plain and in the Mid-West of the United States is suggested. The magnetic
tracer method was used for assessing the rate of lateral mechanical migration of the products of pedogenesis. The typification
of soil catenas on slopes was performed with the quantitative consideration for the material loss and accumulation rates,
the degree of openness of the soil catenas for the migration fluxes, and the localization of accumulation zones on the slopes. 相似文献
11.
E. A. Gurbanov 《Eurasian Soil Science》2010,43(12):1387-1393
It is found that the differentiation and degradation of soil depend on surface slope, water flow rate, and furrow length. The development of irrigation erosion on irrigated areas results in the formation of three zones: erosion, stabilization, and accumulation. The high slopes of irrigated plots favor an intense erosion-accumulation process. Depending on the surface slope and the water flow rate, 0.48–19.40 t of soil is washed away from 1 ha. Irrigation erosion affects the density and porosity of soils, and erosion on the slope is enhanced during the differentiation of soil varieties. The texture of soils becomes coarser in the upper erosion region and finer in the aggraded varieties. On the basis of the quantitative assessment of soil erosion rate, the possible losses in dry matter, humus, and essential nutrients are calculated, as well as their removal with water flows. 相似文献
12.
《CATENA》2001,44(1):69-84
The evolution of soil structure after a forest fire was studied on two zones representatives of a typical Mediterranean Pine forest. These zones were in opposite slope orientation but with similar topographical and pedological characteristics. Changes in soil macro-aggregation and water stable micro-aggregation were monitored seasonally during a year after the fire. The water erosion patterns were also studied from August 1993, immediately after the fire, to the end of 1996.The first 5 cm of soil depth were the most affected by fire temperature, showing clear differences on aggregate distribution and temporal variability between zones. In the north-facing soil, a substantial and gradual recovery on soil aggregation was observed mainly in the fraction greater than 5-mm diameter; this reached an increase of 27% in mass of aggregates. In the south slope, the evolution of aggregation was smooth and restricted to the fraction minor than 0.1 mm. These differences between zones are reflected also in their values on soil cohesiveness and compaction, being lesser in the south-oriented soils. Values of erosion parameters show that both zones have the higher soil losses during the immediate period (4 months) after the fire, being more important in the south zone. This zone produced more sediment and runoff (52.42% and 29.95%, respectively) than north-facing soils for the whole period studied. 相似文献
13.
Experimental studies and the analysis of published data have shown that carbon reserves in soils generally increase upon soil
exclusion from agricultural use. The rate of carbon accumulation in the abandoned soils depends on the soil type, the time
elapsed since the soil abandoning (the restoration period), and the thickness of the layer for which the rate of carbon accumulation
is determined. For the upper 20-cm-thick layer, it varies from 66 to 175 g C/m2 per year in dependence on the type of soil and averages 111 g C/m2 per year. The highest rate is typical of the first 10–15 years of soil restoration. According to our calculations, the carbon
sequestration in the upper 20-cm-thick layer of Russian soils due to changes in land use was 184–673 Mt C in 1990–2005 and
may reach 282–1030 Mt C by 2020. 相似文献
14.
H. J. Fang S. L. Cheng X. P. Zhang A. Z. Liang X. M. Yang C. F. Drury 《Land Degradation \u0026amp; Development》2006,17(1):89-96
Soil organic carbon (SOC) in eroded soil can be redistributed from upper slope positions and deposited and sequestered in depressional areas. However, the SOC lost from soil erosion is normally not considered when soil carbon budgets are derived and this could result in an overestimation of SOC loss from the agricultural areas. The impact of soil redistribution on the SOC budget of a sloping landscape in the Black soil region in Northeast China was studied using the presence of the 137Cs tracer which has been deposited since 1954 and the fly‐ash tracer, which was deposited in 1903. Five landscape positions (summit, shoulder‐, back‐, foot‐ and toe‐slope) were selected and included in this study. The depths of 137Cs and fly ash and the SOC content of the deposition layers were used to calculate the change in C content of the soil in the various landscape positions over the last century. We found that the most severe soil erosion occurred in soils in the shoulder‐slope position followed by the back‐slope and the summit positions. Soil deposition occurred in the toe‐slope position followed by the foot‐slope position. A total of 683 kg C was eroded from the summit, shoulder‐ and back‐slopes (in a 1 m wide strip) over the past 100 years and 418 kg C (about 61·2 per cent) was deposited in the low‐lying areas (foot‐ and toe‐slopes). Over half (61·5 per cent) of the deposition (257 kg SOC) occurred over the past 50 years. Most of the previously reported loss of C from the upper slope positions in the Black soils was in fact sequestered in the deposition areas in the landscape. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
15.
为了研究不同逆坡耕作强度导致的土壤位移对坡面水蚀的影响,以金沙江干热河谷区坡面径流小区为研究对象,在径流小区5°,10°,15°坡面上,进行单宽流量为0.6 m^2/h的放水试验。在10°坡面的下坡位置设置0.05,0.10,0.20 m土层深度,分别代表连续耕作80,69,46年导致下坡位置土壤损失土层变薄情况。通过收集径流小区出口的产流量和产沙量,研究在不同坡度上的不同逆坡耕作强度导致的土壤位移对坡面产流率、产沙率、总流量和总产沙量的影响。结果表明:(1)在10°坡面,耕作年限越长,产流越快,不同耕作强度(年限)的产流率、总产流量、产沙率和总产沙量均表现46年<69年<80年的变化趋势,说明长期逆坡耕作导致的土壤位移加速了坡面水蚀的发生;(2)在耕作69年的坡面,坡度越大,产流越快。在测定坡度范围,产流率、总产流量、产沙率和总产沙量均表现出5°<10°<15°的变化趋势,即坡度的增加明显增大了坡面水蚀;(3)随耕作侵蚀强度的增大,坡面产流率与产沙率间的指数增长关系越显著,而坡度的增大弱化了水沙指数函数关系。研究成果可为揭示干热河谷区逆坡耕作强度和坡度对水蚀的作用机理提供参考。 相似文献
16.
A detailed study of the soil cover of a sinkhole (300 m2) in the dry steppe landscape of the Bogdinsk–Baskunchak Natural Reserve in Astrakhan oblast has been performed, and the factors of its differentiation have been analyzed. The indices of pedodiversity have been calculated and compared for karst sinkholes in the dry steppe and northern taiga landscapes. Quantitative parameters of the lateral migration of solid soil substances on the slopes of the sinkhole have been determined. The rate of soil erosion decreases from the slope of southern aspect to the slopes of western, northern, and eastern aspects. On the average, it is estimated at 0.4 mm/yr. The average rate of accumulation of solid substances on the lower parts of the slopes and in the bottom of the sinkhole reaches 0.74 mm/yr. A comparative analysis of the soil properties attests to their dependence on the particular position of a given soil within the sinkhole. Downward the slopes of the sinkhole, full-profile brown arid soils (Cambic Calcisols) are replaced by sierozem-like soils (Haplic Calcisols), light-humus poorly developed soils (Luvisols), lithozems (Leptosols), and stratified soils (stratozems, or Colluvic Regosols). The soils within the upper ring-shape soil microzone are more diverse and contrasting with respect to their morphological, physical, chemical, and physicochemical properties. The degree of soil contrasts decreases down the slopes of the sinkhole towards its bottom. The studied sinkhole is characterized by considerable pedodiversity. Quantitative parameters of pedodiversity for the sinkhole in the dry steppe zone are higher than those form the sinkholes in the northern taiga zone. 相似文献
17.
间歇降雨对红壤坡面土壤侵蚀特征的影响 总被引：4，自引：2，他引：2
自然条件下降雨多以间歇形式出现,而坡面土壤侵蚀又是一个渐变发育的复杂过程。通过3个雨强(60,90,120 mm/h)、5个坡度(5°,10°,15°,20°,25°)下的15场室内模拟降雨,研究一、二次降雨条件下不同雨强、坡度及降雨量对红壤坡面径流和侵蚀过程的影响,探讨间歇降雨条件下坡面侵蚀发育过程及其主要影响因素的变化。结果表明:(1)二次降雨的产流时间相比一次降雨均提前,一次降雨径流总量受到雨强、坡度和降雨量的共同影响,15°坡度是径流总量变化的一个转折点,二次降雨时降雨量的作用减弱,各雨强下的最大相差倍数减小,各坡度之间的倍数差距也减小。(2)一次降雨发生细沟侵蚀最主要的动力是降雨强度,大雨强、陡坡情况下细沟侵蚀更容易产生,而15°坡度对细沟侵蚀的产生具有重要作用,此时若发生细沟侵蚀,坡面侵蚀则多以细沟侵蚀为主,二者侵蚀量呈正比例函数关系,二次降雨的细沟侵蚀量和一次降雨过程中细沟发育情况相关,一次降雨的细沟发育越剧烈,二次降雨的细沟侵蚀量越少,此时细沟侵蚀量和总侵蚀量呈一次函数关系。总体来说,侵蚀总量的变化和细沟发育所处阶段紧密相关。(3)间歇降雨条件下,不同雨强、坡度、降雨量对坡面土壤径流和侵蚀过程的影响存在差异;同时,一次降雨土壤径流和侵蚀的变化对后期二次降雨径流和侵蚀的发展具有重要影响,使得在不同土壤侵蚀发展阶段,雨强、坡度、降雨量等因子对坡面土壤径流和侵蚀影响的程度也随之改变。 相似文献
18.
Environmental magnetism, elemental chemistry, pollen, macrofossil, and radioisotopes were studied on top-metre cores from Ballydoo Lough, Connemara, western Ireland, to reconstruct the impact of changing farming practices on soil erosion in a lake catchment. Documentary evidence, including detailed agricultural statistics, gave an independent land-use history over the period represented in the sediment record, i.e. most of the last two centuries. Maximum soil erosion, which involved unweathered coarse material as well as topsoil, was associated with a rapidly rising rural population and increased arable activity during the early 19th century. The Great Famine (1845–1847) halved the population, but arable and especially pastoral farming quickly recovered and were maintained at a high level from the late 1850s until the late 1890s. During this time, the rate of soil erosion slowed down considerably and the contribution of coarse mineral material relative to topsoil declined. Erosion of peaty soils was less important as potato cultivation declined and the middle slopes of the catchment were no longer cultivated. From the end of the 18th century to the 1970s, sediment accumulation and erosion rates were less and progressive podzolisation occurred as pastoral and particularly arable farming declined. The uppermost sediments record a sharp increase in soil erosion, involving mainly organic-rich soils from the upper slopes. This increase is attributed to a sharp rise in livestock numbers, especially sheep. A feature of the pollen record is the high arboreal pollen representation (43%–66% of total terrestrial pollen), which consists mainly of secondary pollen. It indicates a substantial input of pollen-bearing organic detritus derived from peaty soils and peat cuttings in the catchment. 相似文献
19.
黄土区城市工程建设产生了大量黄土堆填边坡,因其结构松散,缺乏必要防护,水土流失严重。该研究基于野外调查,设计室内堆填边坡降雨冲刷模型试验,分析其侵蚀破坏过程中含水率和基质吸力的响应变化规律,结合水土动力学原理,分析了降雨切沟侵蚀阶段沟坡坍塌破坏机理,并揭示了坡度对侵蚀产沙量的影响。结果表明：1）随坡度增大,坡顶含水率饱和速率加快,边坡基质吸力响应速率先增后减,且在40°范围内响应速率最快,在此坡度附近需更加注重坡面防护和坡脚排水。2）切沟侵蚀阶段,沟坡坍塌破坏为水力-重力复合侵蚀过程,且坡度越大,越容易达到临界破裂角,沟坡重力侵蚀现象越普遍。3）黄土堆填边坡在极端降雨条件下,其临界坡度在41°附近。该研究成果可为黄土区工程堆积体的地质灾害防治及水土流失综合治理提供理论支持。 相似文献
20.
Changes in β-glucosidase enzyme–humic complexes and conventional parameters (pH, total organic C, total N, water-soluble C,
and bulk density) were studied in an almond-cropped soil prone to erosion under a rehabilitation practice. The experimental
plan included three soil slopes (0%, 2%, and 6%) and two type of fertilization (organic and mineral), with sampling of rhizosphere
and inter-row soils. The enzyme humic complexes were extracted by pyrophosphate, purified by ultrafiltration of the organic
extracts on molecular mass exclusion membranes (mol wt > 104) and fractionated by isoelectric focusing technique (IEF). The IEF on polyacrylamide rod gels with a restricted pH gradient
ranging between 6.0 and 4.0 gave five humic bands on the basis of the little differences of their electric charges (pI). Under both organic and mineral fertilization, β-glucosidase activity bound to the fractionated humic substances, especially
in the pH range 4.5–4.2 of the rhizosphere soil, was higher than that of the inter-row soil. This also occurred in 6% slope
where the enzyme activity was lower than in soil with lower slopes. The higher number of the β-glucosidase active humic bands
in rhizosphere than inter-row soil, particularly for the 0% slope, may be due to the presence of humic molecules capable of
preserving the enzyme molecules in the active form, other than to the higher microbial activity synthesizing and releasing
the tested enzymes. 相似文献