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1.
Better understanding of how the loess soils respond to topography and land use under catchment‐scale vegetation restoration is needed to enable science‐based land management interventions for the policy‐driven “Grain‐for‐Green” eco‐restoration program in the Loess Plateau of China. The objective of this study was to characterize the relationships of four selected soil quality indicators to land use under vegetation restoration and topography for a small catchment (0·58 km2) in the Loess Plateau. The major land uses established in the catchment are cropland, fallow (i.e., natural revegetation), grassland, and jujube orchard. The four soil quality indicators were soil organic carbon (SOC), soil total nitrogen (STN), soil total phosphorus (STP), and mean root zone soil water content during the wet season (MRZSWwet). SOC, STN, and MRZSWwet were significantly different (p < 0·05) for different land uses. Grassland showed the highest values for these three properties, whereas cropland had relatively low values for SOC and STN. Land use had no effect on STP, although the lowest value was observed in grassland. Spatial analysis showed that various relations between soil quality indicators and topography (slope and elevation) were observed. These relations were generally weak for most of them, and they varied with land uses. Further analyses indicated that land uses, slope, and elevation had significant effects on the relations between different soil quality indicators. The results here should provide useful information for the further development of “Grain‐for‐Green” program. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
2.
Sumita Chandel M. S. Hadda A. K. Mahal 《Communications in Soil Science and Plant Analysis》2018,49(6):658-674
Soil quality degradation is a major challenge in submontane Punjab. This poses a great threat to soil quality of this particular area. Thus, a study was conducted to address the selection of most appropriate soil quality indicators and to know the status of soil quality in the area under different land uses. Principal component analysis (PCA) approach was employed to get the minimum data set. Geo-referred soil samples were collected from five different land uses and analyzed for different physical, chemical, and biological attributes. The PCA was performed which screened out the five principal components (PCs) with eigenvalue >1. Soil quality index was highest under the land use forest (0.80) followed by grasses (0.79), horticulture (0.78), cultivated (0.75), and bare (0.67). The organic carbon contributed maximum to soil quality (28.5%) followed by available K (19.4%), electrical conductivity (18.3%), K-factor of universal soil loss equation (USLE) (14.9%), plant available water (10.5%), and clay (8.3%). Conclusively, the study area falls under the medium category of soil quality. 相似文献
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4.
This study assessed the soil organic C (SOC) and soil nutrients in smallholding home garden, woodlot, grazing land, and cropland at two soil depths and two sites in Wolaita Zone, southern Ethiopia. The results showed that soil properties were significantly influenced by land use. The home garden had significantly higher (p < 0.05) SOC and soil nutrients when compared to the cropland. When the home garden was compared to the woodlot and grazing land uses, it had significantly higher (p < 0.05) values except in SOC, total N (TN), cation exchange capacity (CEC), and exchangeable Ca. Cropland, in comparison with grazing land and woodlot, had a non‐significant difference except TN. The SOC stock (0–40 cm) in the home garden, woodlot, grazing land and cropland was 79.5, 68.0, 65.0, and 58.1 Mg ha?1, respectively. Home garden significantly differed (p ≤ 0.05) in SOC only from cropland, and this was attributed not only to the relatively higher organic input in the home garden but also to the little organic matter input and frequently tillage of the cropland. The similar SOC among the home garden, woodlot and grazing lands may imply that the balance between inputs and outputs could be nearly similar for the land uses. Soil TN and CEC had a nearly similar pattern of difference as in SOC among the land uses because of their close relationship with SOC. In general, the land use influence on soil nutrients can be in the order: home garden > wood land ≈ grazing land ≈ cropland, with home garden showing the least difference from the woodlot and the greatest from the cropland. In the agroecosystem, in general, the influence of smallholding home garden on SOC and soil nutrient was marginally different from Eucalyptus woodlot and grazing lands but evidently different from cropland. 相似文献
5.
为了对山西省山区土壤干旱程度和水资源利用情况进行研究,通过称重法研究了山西榆次区不同植被(樱桃林地、耕地、枣树林地和杨树林地)及撂荒地土壤剖面水分变化特征、水分有效性及干燥化效应。结果表明:土壤平均含水量从小到大依次为杨树林地(8.10%)、枣树林地(9.94%)、撂荒地(10.70%)、樱桃林地(14.47%)和耕地(14.53%)。各植被下土层均有不同程度的干层发育,其中耕地和樱桃林地土壤为轻度干层,撂荒地主要为中度干层,而枣树林地与杨树林地则发育了中重度干层。杨树林地各土层均为无效水,枣树林地以无效水为主,撂荒地以无效水与难效水为主,耕地和樱桃林地受灌溉补给,以难效水与中效水为主。各植被中除杨树林地外,土壤水分含量均随土层深度增加先减后增。其中樱桃林地和枣树林地土壤水分都在0—3 m内呈递减趋势,3—5 m土壤水分迅速升高。耕地和撂荒地土壤含水量先减后增,均在2—2.5 m深度土层为含水量低值拐点。杨树林地土壤水分在0—3.5 m保持平稳,3.5—5 m水分呈下降趋势。 相似文献
6.
喀斯特石漠化区不同土地利用方式下土壤有机碳分布特征 总被引：12，自引：3，他引：9
为探究喀斯特土壤有机碳分布特征及其对人为干扰的响应,挖掘了2 854个土壤剖面,采集了22 786个土壤样品,分析了贵州省不同土地利用方式下土壤有机碳分布规律;并结合贵州省石漠化防治规划,初步估算了石漠化防治工程的土壤碳增汇贡献。结果表明:贵州省土壤有机碳呈现含量高、密度小的特征。表层土壤(0-20cm)有机碳平均含量25.07g/kg,平均密度仅为4.27kg/m~2。不同用地类型土壤表层有机碳含量大小为灌木林地乔灌木林地灌草地乔木林地弃耕地与荒地草地水田园地旱地与坡耕地;表层碳密度大小为水田灌木林地乔木林地乔灌木林地弃耕地与荒地灌草地旱地与坡耕地草地园地。0-60cm土层土壤有机碳含量对人为干扰较为敏感,60-100cm土层土壤有机碳含量差异较小。实施退耕还林,人工种草及人工造林等石漠化防治工程会明显促进土壤有机碳的积累,到2050年,贵州省0-10,0-20,0-30,0-100cm土层土壤有机碳将增加1.99×10~(13),3.37×10~(13),4.45×10~(13),6.29×10~(13) g。可见,喀斯特地区土壤有机碳具有含量高、密度低的显著特征,石漠化治理能有效增加喀斯特地区土壤碳汇。 相似文献
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The application of geotextile mats constructed from the palm leaves of Borassus aethiopum (Borassus) and Mauritia flexuosa (Buriti) was investigated in field experiments. The use of geotextiles caused improved soil moisture storage during dry summer periods on a steep (21–25°) roadside slope in Lithuania. The enhanced soil moisture under the Borassus and Buriti mats encouraged better root development of perennial grasses, increased the number and weight of earthworms and increased the dry biomass of perennial grasses by 50.5 and 18.2%, respectively, compared with a grassland control. The mean rate of water erosion from bare soil during the study period from 17/04/2007 to 11/12/2008 was 33.21 Mg/ha. The cover of palm‐mat geotextiles decreased soil losses from bare fallow soil by 94.8–91.1%. An erosion rate of 0.85 Mg/ha over this 21‐month period was measured on the slope under perennial grasses without geotextile cover. Application of geotextile cover on perennial grasses completely prevented soil erosion by water. Therefore, use of geotextiles has clear soil and water conservation benefits on industrial slopes susceptible to erosion. The use of geotextiles has multiple benefits including soil conservation, the improvement of plant growth conditions and the encouragement of earthworm populations. 相似文献
8.
梯田玉米土壤水分动态研究 总被引：2，自引：1，他引：2
依据田间试验资料，对梯田玉米土壤水分动态特征进行了研究。并以谷子和休闲地作为对比，对不同植被覆盖条件下的梯田土壤水分差异进行了探讨。结果表明：（1）雨季降水对玉米地土壤水分的补给起着重要的作用，其土壤贮水量动态与年内的降雨周期相吻合；（2）不同植被覆盖条件对梯田土壤水分状况影响较大，玉米、谷子全生育期的农田蒸散量分别为502．9mm和473．9mm，同期对照休闲地的蒸散量仅为414．1mm；（3）玉米全生育期ET／E0（农田蒸散量／同期水面蒸发量）的比值为0．77，并且在拔节期和抽雄期都大于1，而谷子全生育期该值为0．69。 相似文献
9.
Soil organic carbon,nitrogen, and phosphorus distribution in stable aggregates of an Ultisol under contrasting land use and management history 总被引：1，自引：0，他引：1 
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下载免费PDF全文 Different land‐use affects the organization of mineral soil particles and soil organic components into aggregates and the consequent arrangement of the aggregates will influence essential ecosystem functions. We investigated a continuous rubber plantation (forested), land fallowed for 10 y (fallow), 10‐y continuous arable cropping land and cropped land with top soil removed (TSR) for concentrations of C, N, and P in bulk soil and dry aggregates. Results showed that a high level of soil disturbance decreased the proportion of surface (0–15 cm) soil aggregate stability (low mean weight diameter) in TSR by 149% and arable cropping by 125% compared with the forested. Aggregate associated SOC was higher in aggregate‐size fractions of forested land‐use when compared with that in 10‐y fallow, continuous arable cropping, and TSR. For aggregate associated N, fallow and forested land‐use types concentrated higher proportion across aggregate sizes than the arable cropping and TSR. Macro aggregate fractions generally contained higher concentrations of C, N, and P compared with the micro‐aggregates. Water transmission indicators like total porosity and saturated hydraulic conductivity recorded higher values with forested and fallow land‐use than the others. We can thus conclude that long‐term soil disturbance due to cultivation and removal of top soil reduces the accumulation of soil C, N, and P in bulk soil and decreases water transmission properties. On the other hand, aggregate‐associated C, N and P accumulations are dependent on the level of soil surface disturbance and aggregate sizes. 相似文献
10.
Soil organic carbon as affected by land use in young and old reclaimed regions of a coastal estuary wetland,China 总被引：1，自引：0，他引：1
Soil organic carbon (SOC) and selected soil properties were measured in fringe and ditch marshes and cropland of old and young reclaimed areas in a subtropical estuary in China in order to investigate the effects of land use and reclamation history on SOC. The results show that after the conversion of wetlands to cropland, a longer reclamation history (>20 yr) resulted in greater soil bulk density, salinity, clay and silt, and lower soil moisture, SOC and sand content, whereas a shorter reclamation history (<20 yr) induced smaller values for soil pH, moisture and sand. Ditch marshes had greater average SOC in the top 50 cm than fringe marshes and cropland. SOC decreased generally down soil profiles from 0 to 50 cm in depth, except for the obvious accumulation of SOC in deeper soils from old fringe and young ditch marshes. Ditch marshes had the greatest SOC densities in the top 50 cm in both regions compared to the other land uses. SOC densities in the top 50 cm were less in croplands than in fringe marshes in the young region, while there were no significant differences between them in the older one. Except for cropland, SOC densities in the top 50 cm of the fringe or ditch marshes in the old region were not significantly different from those in the young region. SOC in both regions was reduced by 13.53 × 104 t (12.98%) in the top 50 cm of the marshes after conversion to cropland, whereas the regional SOC storage increased by 29.25 t when ditch marshes were included. The results from regression analysis show that bulk density and soil moisture significantly influenced SOC. The total SOC stored in both ditch marshes and croplands was higher compared to fringe marshes. The regional SOC storage in the top 50 cm was not reduced after reclamation due to C accumulation in the ditch marshes. The regional effects of cultural practices should be taken into account in devising strategies for managing soils in coastal wetlands, particularly in the developing world. 相似文献
11.
E. V. Dubovik 《Eurasian Soil Science》2012,45(3):303-308
The alteration of the typical chernozem structure under long fallow, black fallow, and perennial grasses under the impact
of sprinkling were studied. The changes in the macrostructural status of the soil were objectively estimated from the results
of two coupled analysis methods. It was found that the most important changes in the aggregate-structural status occurred
in the soil under black fallow and perennial grasses; long-fallow lands were the most stable and resistant to external impacts.
Soil classes characterizing the quality of the soil structure in terms of the aggregation and water stability were proposed.
As a result of the sprinkling, the soil structure quality of the long-fallow land changed from good (classes IVa–IVb) to medium
(IIIb–IIIc), that of the black fallow changed from good and medium (classes IVa–IIIb) to poor (classes IIa, IIb, and IIc),
and the structure quality of the soil under perennial grasses changed from medium and poor (IIIb–IIb) to poor and even unsatisfactory
(classes IIb–Ic). 相似文献
12.
对中国科学院沈阳生态实验站潮棕壤水稻田、玉米地、撂荒地和人工林地4种土地利用方式经过14年后在0~150 cm土体10个土层中土壤比表面的剖面分布进行比较研究的结果表明,不同土地利用方式及不同深度土层土壤比表面差异显著,除林地0~5 cm表层外,4种土地利用方式在80 cm以内深度的土层中土壤比表面随剖面深度增加呈渐次增大的趋势,说明林地表层高有机碳积累对土壤比表面增加可能产生了重要影响。150 cm深度土壤比表面平均值为林地>玉米地>撂荒地>水稻田。土壤比表面与土壤风干含水量及交换性盐基总量呈极显著正相关关系:水稻田、玉米地、撂荒地、林地中土壤比表面与风干含水量相关系数分别为0.767、0.911、0.943、0.953(n=30,P<0.001);与土壤交换性盐基总量的相关系数分别为0.877、0.978、0.673、0.780(n=30,P<0.001)。不同利用方式下土壤比表面与土壤有机碳、全氮、碱解氮呈显著负相关关系,与土壤pH、硫、磷之间的关系因土地利用方式不同而具有一定的差异。研究结果表明,土壤比表面可作为指征不同土地利用方式对土壤理化性质影响的可行的土壤物理学指标,测定不同土壤的比表面可以基本反映出土壤交换性能的差异。 相似文献
13.
Burhan U. Choudhury Abdul R. Fiyaz Kamal P. Mohapatra Shishomvanao Ngachan 《Land Degradation \u0026amp; Development》2016,27(4):1163-1174
In the fragile hilly ecosystem of North‐eastern Himalayan Region (NEHR) of India, interaction of land use change and soil organic carbon (SOC) holds significance in sustaining land productivity. However, because of limited data, the effect of land use on SOC inventory at regional level is poorly quantified. The present study assessed the influence of seven major land uses and agrophysical variables (soil texture, bulk density, annual rainfall and mean temperature) on SOC concentration and stock across altitudinal gradients (6–3,500 masl) of NEHR of India. Results revealed that non‐agricultural land uses (grasslands and forests) registered significantly higher SOC concentration (2·20 to 2·51%) and stock (35·2–42·1 Mg ha−1) compared with agricultural (shifting and settled‐up and lowlands), plantation and horticultural land uses (SOC, 1·44 to 1·63%; stock, 27·4–28·4 Mg ha−1). Principal component analysis exhibited that the variation in SOC concentration among the land uses was mostly contributed by finer fractions of soil separates (silt and clay contents), and altitudinal gradient led variation in climatic variables (rainfall and temperature). Trend analyses depicted that SOC increased with an increase in rainfall and clay content but decreased with mean temperature and soil bulk density. Along the altitudinal gradient (6 to 1,000 masl), an inconsistent increase in silt + clay, annual rainfall, SOC concentration, and stock was also observed. However, beyond 1,000 masl, the corresponding increase was linear. The wide variability in SOC concentration and stock, therefore, resulted from the interaction of land uses, altitudinal gradients, textural gradients and climatic variables Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
14.
Soil organic carbon distribution in relation to land use and its storage in a small watershed of the Loess Plateau, China 总被引：2，自引：0，他引：2
Soil organic carbon (SOC) is an important component in agricultural soil, and its stock is a major part of global carbon stocks. Estimating the SOC distribution and storage is important for improving soil quality and SOC sequestration. This study evaluated the SOC distribution different land uses and estimated the SOC storage by classifying the study area by land use in a small watershed on the Loess Plateau. The results showed that the SOC content and density were affected by land use. The SOC content for shrubland and natural grassland was significantly higher than for other land uses, and cropland had the lowest SOC content. The effect of land use on the SOC content was more significant in the 0-10 cm soil layer than in other soil layers. For every type of land use, the SOC content decreased with soil depth. The highest SOC density (0-60 cm) in the study area was found in shrublandII (Hippophae rhamnoides), and the other land uses decreased in the SOC density as follows: natural grassland > shrublandI (Caragana korshinskii) > abandoned cropland > orchard > level ground cropland > terrace cropland > artificial grassland. Shrubland and natural grassland were the most efficient types for SOC sequestration, followed by abandoned cropland. The SOC stock (0-60 cm) in this study was 23,584.77 t with a mean SOC density of 4.64 (0-60 cm). 相似文献
15.
水热对三峡水库消落带退耕稻田土壤有机碳矿化的影响 总被引：1，自引：0，他引：1
采用模拟培养的方法,研究了不同水热条件对三峡水库消落带退耕稻田土壤有机碳(SOC)矿化的影响。试验共设3个培养温度(10、20和30℃)和4个水分梯度(40%田间持水量(WHC)、70%WHC、100%WHC和浅层淹水)。结果表明:1在66天培养期内,各培养温度(10~30℃)下,70%WHC、100%WHC和浅层淹水处理之间的SOC累积矿化量均无明显差异,其中10℃培养时40%WHC处理下的累积矿化量要显著低于70%WHC和100%WHC水分处理(P0.05),但与浅层淹水无明显差异,而20℃和30℃培养时40%WHC处理下的累积矿化量则要显著低于其他水分处理,表明相较于70%WHC的水分处理,40%WHC水分处理会抑制消落带退耕稻田SOC矿化,而高水分(100%WHC和浅层淹水)对SOC矿化则无明显促进和抑制作用。2在相同水分条件下,消落带退耕稻田SOC累积矿化量均随培养温度升高而增加。3高温下各水分处理之间的温度敏感性无显著差异,而低温下水分对温度敏感性有显著影响,低温浅层淹水处理下的Q10为2.33,显著高于40%WHC处理,与70%WHC和100%WHC处理之间无明显差异。且随着温度升高,浅层淹水下消落带退耕稻田SOC矿化的温度敏感性显著降低,而在土壤含水量≤100%WHC下则无明显变化。温度和水分均能显著影响SOC矿化,但二者无明显的交互效应。4双库一级矿化动力学模型拟合结果表明,水分和温度通过影响消落带退耕稻田土壤易分解有机碳含量和难分解有机碳的矿化速率,从而影响SOC矿化。 相似文献
16.
Abstract. To assess the effect of different land uses on soil properties, five land use types (fallow, Gmelina , arable, secondary forest and cocoa plots) on a sandy loam Alfisol (Typic Kandiudalf) were compared in terms of surface (0–15 cm) soil pH, exchangeable acidity, K, Ca and Mg, extractable P, total N, organic matter, gravimetric moisture, temperature and bulk density. There were significant differences ( P ≤ 0.05- P ≤ 0.001) between the land use types for all the properties except exchangeable acidity and moisture. All the land use types differed significantly from each other in at least four properties. Fallow and secondary forest differed in nine properties, fallow and cocoa in seven and fallow and Gmelina in six. In terms of the number of properties with high variability (CV ≥ 35%), the order was arable, secondary forest and cocoa (4) > Gmelina (3) > fallow (1). 相似文献
17.
黄土丘陵沟壑区小流域土壤水分空间变异性及其影响因素 总被引：1，自引：0，他引：1
为了解不同土地利用方式和地形条件下土壤含水率的数量特征及其变异规律,以黄土高原丘陵沟壑区纸坊沟小流域为研究对象,利用经典统计学方法系统分析了小流域尺度土壤含水率的空间变异性。结果表明:不同土地利用方式下土壤平均含水率之间呈极显著差异,其顺序为:农田>草地>林地>灌木地;土壤含水率在土壤剖面上呈先减小后增大的趋势。地形条件显著影响土壤含水率,其中梯田>沟底>坡地>峁顶;不同坡位土壤含水率的顺序为坡下>坡上>坡中,不同坡向间为阴坡>阳坡。上述土壤含水量的变异程度均为中等。在小流域尺度,土地利用和地形对土壤水分具有显著的交互作用。相关结果可为黄土丘陵沟壑区的土壤水分管理、土地利用结构优化、不同地形条件下的植被布局提供参考。 相似文献
18.
《Land Degradation \u0026amp; Development》2017,28(3):983-993
An accurate estimation of soil organic carbon (SOC) is important for the evaluation and management of carbon (C) flux in terrestrial ecosystems. However, there is little work on the spatial variability of SOC in deep soils and its driving factors. Thus, the objective of the study was to derive the primary factors dominating the spatial distribution of SOC in different soil layers with the use of the autoregressive state‐space approach. The concentration of SOC was measured to the depth of 500 cm (n = 86) along a south–north transect of China's Loess Plateau. The mean SOC of the 500‐cm soil profile generally decreased from south to north following the decreasing rainfall gradient. Based on the investigated factors, the state‐space model was able to capture 90.3–99.9% of the spatial variability of SOC in the various soil layers. According to the coefficients in the optimal state‐space model for each soil layer, climatic factors such as precipitation and temperature had a dominant control over the spatial distribution of SOC at shallow depths. However, both climatic and edaphic (e.g. soil texture) factors, and to a small extent land use, influenced the spatial behavior of SOC at the 40–200 cm soil depth. For soil layers below 200 cm, the importance of land use was revealed, and the spatial characteristics of SOC were together driven by land use, climatic and edaphic factors. This is critical for the management of soil C flux in deep soils and the C stock and cycle in terrestrial ecosystems. Table SI. Basic properties of soils and climate and elevation under three land uses along the south–north transect on the Loess Plateau (mean ± standard deviation). Note that SWC is gravimetric soil water content. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
19.
不同利用方式对潮棕壤交换性钾钠及盐基总量的影响 总被引：2，自引：0，他引：2
为深刻认识土地利用变化对土壤交换性离子的影响,本文对潮棕壤水稻田、玉米地、撂荒地和人工林地4种土地利用方式经过14年后,在0～150cm剖面中土壤交换性钾、钠、交换性盐基总量的剖面分布及交换性钾钠比值变化进行了比较研究。结果表明,林地和撂荒地各土层交换性K含量及土体中交换性K储量具有高于水稻田和玉米地的趋势;水稻田和撂荒地0～20cm各土层的交换性Na含量显著高于林地和玉米地;林地0～150cm深度土壤交换性Na储量显著高于其他三种利用方式(P<0.05);0～150cm深度内土壤交换性盐基总储量大小依次为林地、玉米地、撂荒地、水稻田;水稻田剖面土壤交换性K/Na随土层深度增加而增大,其他3种土地利用方式则是随土层深度增加而降低。土壤管理和植物自身的特性在土壤剖面中交换性离子的构成以及土壤交换性盐基库的重建等方面可能起到重要作用。 相似文献
20.
Switchgrass (Panicum virgatum L.) is a perennial biofuel crop with a high production potential and suitable for growth on marginal land. This study investigates the long-term planting effect of switchgrass on the dynamics of soil moisture, pH, organic carbon (SOC), total nitrogen (TN), nitrate nitrogen (NO3–-N) and ammonium nitrogen (NH4+-N) for soils to a depth of 90-cm in a sandy wasteland, Inner Mongolia, China. After crop harvesting in 2015, soil samples were collected from under switchgrass stands established in 2006, 2008, and 2009, native mixture, and a control that was virgin sand. Averaged across six layers, soil moisture and pH was significantly higher under the native mixture than switchgrass or virgin sand. However, SOC and TN were significantly higher under the 2006 switchgrass stand when compared with all other vegetation treatments and the control. The SOC and TN increased from 2.37 and 0.26 g kg?1, respectively, for 2009 switchgrass stand, and to 3.21 and 0.42 g kg?1, respectively, for 2006 switchgrass stand. Meanwhile, SOC and TN contents were 2.51 and 0.27 g kg?1, respectively, under the native mixture. The soil beneath switchgrass and native mixture showed the highest NO3–-N and NH4+-N, respectively. The soil moisture increased with depth while SOC, TN, and NO3–-N decreased. An obvious trend of increasing moisture, SOC, TN, and mineral N was observed with increasing switchgrass stand age. Thus, growing switchgrass on sandy soils can enhance SOC and TN, improve the availability of mineral N, and generate more appropriate pH conditions for this energy cropping system. 相似文献