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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.
Soil microbial communities are very sensitive to changes in land use and are often used as indicators of soil fertility. We evaluated the microbial communities in the soils of four types of vegetation (cropland (CP), natural grassland (NG), broadleaf forest (BF) and coniferous forest (CF)) at depths of 0–10 and 10–20 cm on the Loess Plateau in China using phospholipid fatty acid (PLFA) profiling and denaturing gradient gel electrophoresis (DGGE) of DNA amplicons from polymerase chain reactions. The soil microbial communities were affected more by vegetation type than by soil depth. Total organic carbon, total nitrogen, soil-water content, pH, bulk density (BD) and C:N ratio were all significantly associated with the composition of the communities. Total PLFA, bacterial PLFA and fungal PLFA were significantly higher in the BF than the CP. The DGGE analyses showed that NG had the most diverse bacterial and fungal communities. These results confirmed the significant effect of vegetation type on soil microbial communities. BFs and natural grass were better than the CFs for the restoration of vegetation on the Loess Plateau. 相似文献
3.
黄土丘陵区小流域植被恢复的土壤养分效应研究 总被引：55，自引：5，他引：55
研究了安家坡小流域荒草地、山杏林地、农地、油松林地、灌木林地、弃耕地等地类的土壤养分特征。结果表明,植被系统具有较强的养分表层富集功能;不同植被恢复类型对土壤养分含量有明显的影响,主要表现在不同土层土壤有机质、速效磷、速效钾、硝态氮和铵态氮含量在不同植被类型间存在显著的差异性;人工灌木植被对土壤的培肥作用高于乔木植被;农地弃耕(撂荒)有一定的土壤培肥作用;对水土流失极为严重的黄土丘陵沟壑区来说,在退耕还林还草时应优先考虑恢复灌木和草本等先锋植被;在土壤质量改善到一定程度时,再进行乔木的间植;农地弃耕是一种节省人力物力而其生态环境效应又很好的双赢途径。 相似文献
4.
Impact of land‐use changes on soil hydraulic properties of Calcaric Regosols on the Loess Plateau,NW China 
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下载免费PDF全文 Miaozi Yu Lulu Zhang Xuexuan Xu Karl‐Heinz Feger Yanhui Wang Wenzhao Liu Kai Schwärzel 《植物养料与土壤学杂志》2015,178(3):486-498
Vegetation restoration efforts (planting trees and grass) have been effective in controlling soil erosion on the Loess Plateau (NW China). Shifts in land cover result in modifications of soil properties. Yet, whether the hydraulic properties have also been improved by vegetation restoration is still not clear. The objective of this paper was to understand how vegetation restoration alters soil structure and related soil hydraulic properties such as permeability and soil water storage capacity. Three adjacent sites with similar soil texture, soil type, and topography, but different land cover (black locust forest, grassland, and cropland) were selected in a typical small catchment in the middle reaches of the Yellow River (Loess Plateau). Seasonal variation of soil hydraulic properties in topsoil and subsoil were examined. Our study revealed that land‐use type had a significant impact on field‐saturated, near‐saturated hydraulic conductivity, and soil water characteristics. Specifically, conversion from cropland to grass or forests promotes infiltration capacity as a result of increased saturated hydraulic conductivity, air capacity, and macroporosity. Moreover, conversion from cropland to forest tends to promote the creation of mesopores, which increase soil water‐storage capacity. Tillage of cropland created temporarily well‐structured topsoil but compacted subsoil as indicated by low subsoil saturated hydraulic conductivity, air capacity, and plant‐available water capacity. No impact of land cover conversion on unsaturated hydraulic conductivities at suction > 300 cm was found indicating that changes in land cover do not affect functional meso‐ and microporosity. Our work demonstrates that changes in soil hydraulic properties resulting from soil conservation efforts need to be considered when soil conservation measures shall be implemented in water‐limited regions. For ensuring the sustainability of such measures, the impact of soil conversion on water resources and hydrological processes needs to be further investigated. 相似文献
5.
黄土丘陵区天然和人工植被类型对土壤理化性质的影响 总被引：8，自引：2，他引：6
不同植被类型对黄土高原土壤质量的改善作用存在较大差异。研究天然和人工植被类型对土壤性状的影响差异对于深入认识黄土高原植被恢复与土壤环境演化的关系,准确评价不同植被恢复模式生态环境效益具有重要意义。该研究以黄土丘陵区燕沟流域为例,选择研究区广泛分布的11种天然和人工植被类型为研究对象,系统分析了该区天然和人工植被类型对土壤性状的影响。结果表明:天然和人工植被类型对土壤性状的影响差异明显。200cm土层土壤含水率大小为农田>天然草地>人工乔木林地>果园>人工灌木林地>天然灌木林地。与农田相比,天然灌木林地和天然草地土壤体积质量降低最为明显,人工乔木林地、人工灌木林地和果园土壤体积质量下降差别不明显。天然灌木林地、天然草地和人工灌木林地土壤有机质、全氮都有明显提高,人工乔木林地和果园土壤有机质和全氮提高不明显。不同植被类型土壤有机质、全氮总体随土层加深呈下降趋势,农田、果园和人工乔木林地土壤有机质和全氮垂直变化较小,而天然灌木林地、天然草地和人工灌木林地变化较大。不同植被类型土壤全磷含量差异较小,且垂直变化不明显。总体看来,天然植被类型对该区土壤性状改善作用优于人工植被类型,而人工灌木林的改善作用优于人工乔木林。 相似文献
6.
黄土高原1999年开始的退耕还林（草）工程，对植被覆盖与土地利用结构产生了深刻影响，评估黄土高原未来植被恢复潜力、植树造林适宜区以及土地利用变化，对黄土高原生态保护和高质量发展具有重要意义。该研究基于北洛河流域2020年下垫面状况，借鉴"相似生境法"，对不同地貌类型区的未来恢复潜力、植树造林适宜区与土地利用变化进行了分析。结果表明：1）丘陵沟壑区目前平均植被盖度为61.9%，未来20~30 a仍有9.2%左右的上升空间，植被可恢复土地面积约占丘陵区的36.4%。土石山林区尚有11.5%的土地面积具有恢复余地，高塬沟壑区与阶地平原区植被盖度恢复余地很小。2）未来土地利用变化面积主要集中在丘陵沟壑区，与2020年相比，其耕地将减少47.4%，而林地与草地会增加0.7%与15.8%。土石山林区耕地将减少23.0%，林地与草地分别会增加0.2%与36.0%。3）基于"适地适树"原则下的情景模拟，高塬沟壑区与阶地平原区分别有279.16、233.73 km2面积可植树造林，而丘陵沟壑区大片可退耕土地适宜于自然恢复。结果表明，丘陵沟壑区仍是未来生态恢复重点关注区域，是黄河流域生态保护和高质量发展的热点区域。 相似文献
7.
黄土高原地区是我国水土流失和环境问题严重的地区之一,人工植被恢复可以有效改善土壤性质,提高土壤质量,明确长期人工植被恢复后土壤水分和养分性质的响应差异,有利于进一步有效改善生态环境。选取晋西黄土区自然恢复的次生林地、人工刺槐林地、人工油松林地3种典型植被恢复类型为研究对象,通过测定土壤物理性质以及有机碳、氮磷钾元素含量等土壤养分,对比分析长期不同人工林恢复条件下的差异。结果表明:(1)次生林地、刺槐林地和油松林地在0-20 cm浅层土壤的容重分别1.15,1.04,1.06 g/cm3,次生林地的容重最大,土壤容重随着土层深度的增加而增大;(2)次生林地在浅层的土壤水分状况优于刺槐林地和油松林地,土壤水分消耗期(生长季开始前)过渡到积累期(生长期开始)时,次生林土壤水分动态变化更剧烈;(3)次生林地土壤碳储量较高,油松林地土壤氮、磷储量较高。3种林地土壤养分垂直变化差异显著,且均具有明显的表聚性,有机碳、全氮、全磷、速效氮和速效钾含量均随着土层深度的增加而减少,而速效磷含量随着土层深度的变化表现为先增大再减小。以水养条件为依据,建议在植被恢复过程中多以保育次生林为主来达到较好的水碳储量等生态效益,有利于优化晋西黄土区的林分管理,促进植被恢复和生态建设。 相似文献
8.
黄土高原丘陵区不同土地利用方式对土壤理化性质的影响 总被引：16，自引：0，他引：16
对晋西北黄土高原丘陵区持续利用30年的小叶锦鸡儿人工林、农田、杨树林、小叶锦鸡儿和杨树的混交林地以及撂荒地的土壤理化性状进行了研究。结果表明,不同土地利用方式对土壤理化性质影响很大。小叶锦鸡儿和杨树的混交林以及小叶锦鸡儿人工林可以降低土壤容重,提高土壤酶活性、有机质和全N含量,从而改善土壤肥力。混交林和小叶锦鸡儿人工林的土壤培肥作用高于杨树纯林。粗放的农业耕作措施提高土壤容重,降低土壤养分含量,使土壤退化。撂荒地一定程度上可以起到培肥土壤的作用。在黄土高原丘陵区,种植小叶锦鸡儿人工林以及小叶锦鸡儿和杨树的混交林是较好的生态重建和植被恢复方式。 相似文献
9.
10.
黄土高原丘陵区人工灌草生态系统水土保持功能评估 总被引：3，自引：3，他引：3
人工灌草复合植被是黄土高原植被恢复与重建的主要植被类型,在该区域水土保持中发挥着重要的作用。以定西市安定区为例,基于InVEST模型对该区人工灌草生态系统的水土保持功能进行定量化评估,以期为黄土高原丘陵区生态恢复与水土资源的可持续利用提供决策支撑。评估结果为:(1)人工灌草地单位面积的水源涵养量为369.25 m~3/hm~2,是草地的90.5%、林地的134%和耕地的110%;该区的水源涵养总量为3 970.99×10~4 m~3,人工灌草地水源涵养量占该区总水源涵养量的29.9%。(2)人工灌草地单位面积的N保持量为2.4 kg/hm~2,净化率为72.21%,P保持量为0.12 kg/hm~2,净化率为71.07%。(3)人工灌草地单位面积的土壤保持量为308.76 t/hm~2,比草地、林地和耕地分别高1.88,1.44,6.01倍,该区的土壤保持总量为3 310.21×10~4 t,人工灌草地土壤保持量占总土壤保持量的54.82%。结果表明,人工灌草地的水源涵养能力仅次于草地,高于其他土地利用类型,但土壤保持能力是6种土地类型中最强的,具有较好的水土保持功能,是黄土高原丘陵区适宜的植被类型和土地利用方式。 相似文献
11.
[目的]探究黄土高原植被恢复过程中土壤微生物的演变特征,为黄土高原生态恢复重建工作提供科学参考。[方法]以Web of Science数据库和CNKI数据库中的期刊论文为数据源,运用CiteSpace文献计量工具对黄土高原植被恢复过程中土壤微生物演变的研究概况及研究热点进行分析。[结果]2002—2018年黄土高原植被恢复过程中土壤微生物演变特征相关文献的发表数量随时间呈增长趋势;国内外研究热点主要围绕土壤微生物量、微生物群落结构以及酶活性展开,且对于微生物量的关注度比较高;在植被演替过程中,微生物生物量和酶活性总体增加,微生物群落从贫营养型向富营养型转变,土壤微生物群落结构和功能的进一步改善。不同植被类型对土壤生物质量改善效果不同,总体来说,混交林作用效果最好,刺槐和柠条纯林次之,荒草地和油松纯林最低。[结论]黄土高原植被恢复土壤微生物今后的研究应注重微生物关键种的识别、参与碳氮磷循环的功能微生物以及全球变化对微生物群落影响等方面。 相似文献
12.
There are variations in soil respiration across vegetation types; however, it is unclear which factors are mainly responsible for the variations. A field experiment was conducted in 2008 and 2009 in a semiarid region of China to investigate the daytime and monthly variation of soil respiration across vegetation types and to determine the factors controlling the variation. An automated portable soil carbon dioxide (CO2) flux measurement system was used to measure the soil respiration in shrubland, grassland, fallow land, and cropland during the growing periods. The results showed that the relative daytime variation amplitude of soil respiration in the fallow land and cropland was as small as that of shrubland and grassland during July, but greater than that of shrubland and grassland during August and October. A hysteresis effect for the relationship between the daytime soil respiration and daytime soil temperature was observed for all four vegetation types. There was also a hysteresis effect for the relationship between the daytime soil respiration and daytime air temperature for the grassland. Over the study period, the monthly soil respiration rates of the fallow land and cropland were statistically comparable and significantly lower than those of the shrubland and grassland, with the exception of August, during which the monthly soil respiration of the cropland was as great as that of shrubland and grassland. The factors responsible for the monthly soil respiration variation across the vegetation types differed from month to month. In general, the soil temperature and soil water content were mainly responsible in August and September; however, the root biomass predominated in July and October. The results are valuable for accurately estimating regional carbon fluxes by considering the temporal variability of the soil respiration variation across vegetation types in the Loess Plateau of China. 相似文献
13.
黄土高原是我国水土流失最为严重、生态环境极为脆弱的地区之一，生态环境建设对区域的发展极为重要。白银市区位于甘肃省中部，属典型的黄土高原矿农交错区。恶劣的自然环境和以工业为主体的强烈的人类经济社会活动共同作用，使白银市区产生了诸如水土流失日趋严重、土地退化面积不断扩大、水资源进一步短缺和天然植被遭到人为破坏等生态环境问题。通过对白银市区生态退化的现状及原因的分析，根据恢复生态学、可持续发展原理和生态经济学理论，根据白银市区实际情况，提出了白银市区生态恢复的原则和对策。 相似文献
14.
土壤水分是黄土高原植被恢复及其可持续性的主导限制因子,为认识退耕还林(草)工程以来大尺度植被恢复与土壤水分关系,以25km×25km格点为研究单元,采用1992—2013年逐月降水量、归一化植被指数(NDVI)和土壤水分指数(SWI)等数据,分析了该区植被恢复与土壤水变化过程及其区域分布特征。结果表明,黄土高原植被和土壤水分变化特征和趋势不一致,其中大部分区域(70%以上面积)NDVI呈极显著增加趋势(p0.01),但绝大部分地区(94%面积)的SWI没有趋势性变化。为进一步揭示植被和土壤水分变化关系,以格点为单元提取并分析了相似年组(年降水量差小于2%,年差大于或等于5年,逐月降水量相关性大于0.55),并分析了不同相似年组内NDVI和SWI的变化特征。植被指数与土壤水分变化主要包括两类:植被指数和土壤水分同时增加与植被指数增加而土壤水分减少。黄土高原植被、土壤水分变化的区域性明显,在未来生态恢复过程中,需要进一步认识植被恢复对土壤水分的关系,促进黄土高原植被恢复的可持续性。 相似文献
15.
黄土高原半干旱区不同土地利用下的土壤有机碳、碳组分和土壤营养 总被引：5，自引：0，他引：5
Cropland (CP), native grassland (NG) and two shrub land treatments which were converted from cropland in 1985:seabuckthorn (Hippophae rhamnoides L. ) (ST), and branchytamarisk (Tamarix ramosissima) (BT) were investigated to evaluate effects of land use conversion on soil organic carbon (SOC) and soil nutrients in the semi-arid region of the Loess Plateau of China. Total organic carbon (TOC), light fraction organic carbon (LFOC), heavy fraction organic carbon (HFOC), total N (TN), nitrate nitrogen (NO3--N) and nitrite nitrogen (NO2--N), ammonium nitrogen (NH4+-N), total P, and available P (AP) were measured. The results showed that SOC in NG, ST and BT were 12.7%, 27.7% and 34.8% higher than that of the cropland, respectively. LFOC, light fraction (LF) dry matter, ratio of TOC to TN (C/N) and the ratio of TOC to AP (C/P) were higher in the shrub land or native grassland than in the cropland. Cropland had the highest TN, the sum of NO3--N and NO2--N, TP and AP due to the use of chemical fertilizers. TOC significantly correlated with LFOC, HFOC and C/N. LFOC significantly correlated with dry matter of the LF and C/N. TN, the sum of NO3--N and NO2--N and AP were significantly negatively correlated with TOC and LFOC. Therefore, land use conversion from cropland to shrub land, or maybe grassland, contributed to SOC sequestration and improved soil nutrients stabilization. 相似文献
16.
2000-2015年黄土高原生态系统水源涵养、土壤保持和NPP服务的时空分布与权衡/协同关系 总被引：2，自引：1，他引：1
生态系统服务评估决定区域可持续发展,对人类福祉至关重要。以黄土高原为研究区域,基于CASA、InVEST和RUSLE模型,结合土地利用类型、归一化植被指数、气象等数据,分析了2000年、2005年、2010年和2015年的NPP、土壤保持和水源涵养3项关键生态系统服务的时空分布特征,识别了3种生态系统服务的热点区,并基于相关系数法分析了黄土高原地区和不同气候区(干旱气候区、半干旱气候区、高原气候区、半湿润气候区)不同生态系统服务间的权衡/协同关系。结果表明:(1)2000—2015年,黄土高原地区的土地利用类型变化剧烈,其中林地(2.8%)和建设用地(43.1%)显著增加,耕地(-2.7%)明显减少;(2)2000—2015年,净初级生产力(NPP)、产水量和土壤保持均呈现增长趋势,分别增加14.1%,5.3%和101.3%;(3)黄土高原的4类热点区(非热点区、一类热点区、二类热点区、三类热点区)所占面积变化不显著,分布具有明显的地带性,从西北到东南依次为非热点区、一类热点区、二类热点区和三类热点区;(4)在整个黄土高原地区,土壤保持与NPP、水源涵养之间为协同关系,NPP与水源涵养为权衡关系;在4个气候区,NPP与土壤保持之间的权衡/协同关系与黄土高原地区一致,但土壤保持和水源涵养在半干旱气候区和半湿润气候区呈权衡关系,NPP与水源涵养在高原气候区和半湿润气候区为协同关系。为促进区域生态系统可持续管理,应在土地规划过程中考虑生态系统服务之间的相互关系,尽可能减少权衡,增加协同。 相似文献
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The water-wind erosion crisscross region of the northern Loess Plateau in China is under constant pressure from severe erosion due to its windy and dry climate and intensive human activities. Identifying sustainable land use patterns is key to maintaining ecosystem sustainability in the area. Our aim was to appraise the impacts of different land use regimes on the dynamics of soil total organic C(TOC), total N(TN), and microbes in a typical watershed in the northern Loess Plateau to identify sui... 相似文献
19.
D.L. She L.C. Timm I. Pla Sentís K. Reichardt S.E. Yu 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(4):369-380
Abstract Long-term vegetation restoration carried out on the slopes of the Loess Plateau of China employed different spatial and temporal land-use patterns but very little is known about the effects of these patterns on soil water-content variability. For this study the small Donggou catchment was selected to investigate soil water-content distributions for three spatial scales, including the entire catchment area, sampling transects, and land-use systems. Gravimetric soil water contents were determined incrementally to a soil depth of 1.20 m, on 10 occasions from April to October, 2007, at approximately 20-day intervals. Results indicated that soil water contents were affected by the six land-use types, resulting in four distinct patterns of vertical distribution of soil moisture (uniform, increasing, decreasing, and fluctuating with soil depth). The soil water content and its variation were also influenced in a complex manner by five land-use patterns distributed along transects following the gradients of five similar slopes. These patterns with contrasting hydrological responses in different components, such as forage land (alfalfa)–cropland–shrubland or shrubland–grassland (bunge needlegrass)–cropland–grassland, showed the highest soil water-content variability. Soil water at the catchment scale exhibited a moderate variability for each measurement date, and the variability of soil water content decreased exponentially with increasing soil water content. The minimum sample size for accurate data for use in a hydrological model for the catchment, for example, required many more samples for drier (69) than for wet (10) conditions. To enhance erosion and runoff control, this study suggested two strategies for land management: (i) to create a mosaic pattern by land-use arrangement that located units with higher infiltration capacities downslope from those with lower soil infiltrabilities; and (ii) raising the soil-infiltration capacity of units within the spatial mosaic pattern where possible. 相似文献
20.
Effect of vegetation changes on soil erosion on the loess plateau 总被引：48，自引：0，他引：48
ZHENG Fen-Li 《土壤圈》2006,16(4):420-427
Vegetation is one of the key factors affecting soil erosion on the Loess Plateau. The effects of vegetation destruction and vegetation restoration on soil erosion were quantified using data from long-term field runoff plots established on the eastern slope of the Ziwuling secondary forest region, China and a field survey. The results showed that before the secondary vegetation restoration period （before about 1866-1872）, soil erosion in the Ziwuling region of the Loess Plateau was similar to the current erosion conditions in neighboring regions, where the soil erosion rate now is 8 000 to 10 000 t km^-2 year^-1. After the secondary vegetation restoration, soil erosion was very low; influences of rainfall and slope gradient on soil erosion were small; the vegetation effect on soil erosion was predominant; shallow gully and gully erosion ceased; and sediment deposition occurred in shallow gully and gully channels. In modern times when human activities destroyed secondary forests, soil erosion increased markedly, and erosion rates in the deforested lands reached 10 000 to 24000 t km^-2 year^-1, which was 797 to 1682 times greater than those in the forested land prior to deforestation. Rainfall intensity and landform greatly affected the soil erosion process after deforestation. These results showed that accelerated erosion caused by vegetation destruction played a key role in soil degradation and eco-environmental deterioration in deforested regions. 相似文献