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1.
为揭示不同耕作处理对土壤微生物、酶活性以及养分的影响,利用大豆为材料,采取两种不同耕作方式为主区,4种中耕方式为副区的裂区试验设计。结果表明:旋耕处理的细菌数量在开花期较翻耕处理降低;旋耕处理的真菌数量在成熟期较翻耕处理提高;而放线菌数量在开花期,翻耕处理较旋耕处理提高,到结荚期却显著低于旋耕处理。翻耕处理的脲酶活性除了在鼓粒期低于旋耕处理,在其他生育期均高于旋耕处理;翻耕处理的土壤磷酸酶活性在结荚期、鼓粒期较旋耕处理提高;翻耕处理的土壤蔗糖酶活性在开花期较旋耕处理提高;翻耕处理在开花期与结荚期的过氧化氢酶(CAT)活性较旋耕处理提高。翻耕处理的速效磷含量较旋耕处理显著提高,速效钾含量旋耕处理较翻耕处理显著提高。在不同中耕措施中,土壤细菌数量在开花期RT1、RT2较RCK显著提高;真菌数量在成熟期PT1、PT2、PT3较PCK降低;各时期的放线菌数量PT2与RT2均较高。在各生育期,PT2、RT2的脲酶活性均较高,在开花期PT2较PCK和RT2较RCK显著提高;土壤磷酸酶活性PT2、RT2在各时期亦较高;土壤蔗糖酶活性在大豆成熟期不同处理均高于各自的CK;在大豆成熟期,PT1较PCK和RT1较RCK的CAT活性提高。不同中耕措施的土壤有机质含量除了RT2显著提高外,其他处理间差异不显著,而碱解氮、速效钾含量PT2、RT2均分别显著高于PCK、RCK。综上可知,PT2组合的耕作处理更有利于保护土壤微环境。  相似文献   

2.
The effects of soil tillage and straw management systems on the grain yield and nitrogen use efficiency of winter wheat (Triticum aestivum L. em. Thell.) were evaluated in a cool Atlantic climate, in central Ireland between 2009 and 2011. Two tillage systems, conventional tillage (CT) and reduced tillage (RT) each with and without incorporation of the straw of the preceding crop, were compared at five levels of fertiliser N (0, 140, 180, 220 and 260 kg N ha−1).CT had a significantly higher mean grain yield over the three years but the effect of tillage varied between years. Yields did not differ in 2009 (Year 1), while CT produced significantly higher grain yields in 2010 (Year 2), while RT produced the highest yields in 2011 (Year 3). Straw incorporation had no significant effect in any year.Nitrogen application significantly increased the grain yields of all establishment treatment combinations. Nitrogen use efficiency (NUE) ranged from 14.6 to 62.4 kg grain (85% DM) kg N ha−1 and decreased as N fertiliser rate was increased.The CT system had a significantly higher mean NUE over the three years but the effect of tillage varied with years. While there was no tillage effect in years 1 and 3, CT had a significantly higher NUE than RT in year 2. Straw management system had minimal effect on NUE in any year.The effect of tillage and N rate on soil mineral N content also varied between years. While there was no tillage effect in years 1 and 3, RT had significantly larger soil N contents than CT in the spring before N application, and post-harvest in year 2. N application rates had no effect on soil N in year 1, increased residual N content in year 2 and had an inconsistent effect in year 3. Straw management had no significant effect on soil mineral N content.These results indicate that RT establishment systems can be used to produce similar winter wheat yields to CT systems in a cool Atlantic climate, providing weather conditions at establishment are favourable. The response to nitrogen is similar with both tillage systems where the crop is successfully established. Straw management system has very little effect on crop performance or nitrogen uptake.  相似文献   

3.
Experiments were conducted to evaluate the effect of mouldboard‐ or chisel‐ploughing and rotations on barley crops and associated weeds in a semi‐arid location. Two primary soil tillage operations and eight crop rotation‐tillage operation combinations were evaluated over two successive seasons. Drought conditions prevailed (<152 mm annual precipitation) and affected the measured parameters. Barley grown in mouldboard‐ploughed plots had higher biomass compared with chisel‐ploughed plots. Barley grain yield was greater in mouldboard‐ploughed plots in a fallow‐fallow‐barley rotation. Weed species densities varied between tillage systems and rotations. Density of Hordeum marinum, for example, was high in fallow‐barley‐fallow in chisel‐ploughed plots, and was high under more continuous fallow in mouldboard‐ploughed plots. Similar variations were also observed in weed fresh weights and in numbers of seed produced. The results describe the productivity of barley under extremely dry conditions, where an advantage for mouldboard ploughing was observed. The results also indicate the complexity of weed communities in their response towards different tillage‐rotation combinations.  相似文献   

4.
《Soil Technology》1992,5(1):81-90
Eroded Kandhapludult soils occupy more than 40% of the Southern Piedmont region of the USA. The humid-thermic climate associated with the Ultisols permits double crop residue production ranging from 10 to 14 Mg ha−1 yr−1. Long-term conservation tillage into these crop residues is beneficial in ameliorating the effects of soil erosion. During the course of a five-year study, decomposition of these residues increased soil carbon significantly. Restoration processes were initiated by increasing average soil carbon, representing slight, moderate and severe soil erosion classes, from 0.97 to 2.37% in the 0 to 1.5-cm depth. Accompanying soil carbon responses were increases in soil N, water-stable aggregation and infiltration. Runoff coefficients on conservation tilled restored soils was only 6%, compared to 35% for those conventionally tilled. Rill and interrill soil loss rates were also reduced significantly with surface residue provided with conservation tillage.Restoring Ultisol landscapes with variable levels of soil erosion requires differential fertilization. All fertilizer requirements for severely eroded plots were 1.43 to 2.30-fold higher than those of moderately eroded plots. Because biological N fixation by the crimson clover (Trifolium incarnatum L.) cover crop appeared to be retarded on the severely eroded site, observed plant N stress developed on the irrigated/conservation tillage treatment. Cumulative grain yields of severely eroded site, ranged from 15.4 to 30.3 Mg ha−1 5yr−1, and were statistically equal to or exceeded those of the slightly eroded site. Conservation tillage grain yields were best optimized on the rainfed-moderately eroded site, probably because of the more desirable texture-organic properties of the 13-cm thick Ap horizon. Management of cool-season cover crops with conservation tillage appears essential to restore and sustain crop productivity on eroded Ultisols.  相似文献   

5.
Winter barley is the major crop on semiarid drylands in central Aragon (NE Spain). In this study we compared, under both continuous cropping (BC) (5–6-month fallow) and a crop–fallow rotation (BF) (16–18-month fallow), the effects of three fallow management treatments (conventional tillage, CT; reduced tillage, RT; no-tillage, NT) on the growth, yield and water use efficiency (WUE) of winter barley during three consecutive growing seasons in the 1999–2002 period. Daily precipitation measurements and monthly measurements of soil water storage to a depth of 0.7 m were used to calculate crop water use (ET) and its components. The average growing season precipitation was 195 mm. Above-ground dry matter (DM) and corresponding WUE were high in years with high effective rainfalls (>10 mm day−1) either in autumn or spring. However, the highest values of WUE for grain yield were mainly produced by effective rainfalls during the time from stem elongation to harvest. Despite the similarity in ET for the three tillage treatments, NT provided the lowest DM production, corresponding to a higher soil water loss by evaporation and lower crop transpiration (T), indicated by the lowest T/ET ratio values found under this treatment. No clear differences in crop yield were observed among the tillage treatments in the study period. On average, and regardless of the type of tillage, BF provided the highest values of DM and WUE and yielded 49% more grain than BC. These differences between cropping systems increased when water-limiting conditions occurred in the early stages of crop growth, probably due to the additional soil water storage under BF at sowing. Although no significant differences in precipitation use efficiency (PUE) were observed between BC and BF, PUE was higher under the BC system, which yielded 34% more grain than the BF rotation when yields were adjusted to an annual basis including the length of the fallow. The crop yield under BF was not dependent on the increase in soil water storage at the end of the long fallow. In conclusion, this study has shown that, although conventional tillage can be substituted by reduced or no-tillage systems for fallow management in semiarid dryland cereal production areas in central Aragon, the practice of long-fallowing to increase the cereal crop yields is not longer sustainable.  相似文献   

6.
Despite possible agronomic and environmental benefits, the diffusion of soil conservation tillage systems in Italy is currently rather low. The aim of this study was to compare the performance of different soil tillage techniques, in an effort to identify suitable soil management options for irrigated crops in Central Italy. An experiment was carried out on maize and soybean from April to October in two consecutive years (1993 and 1994) in Maccarese (a coastal location near Rome). The systems compared were: conventional mouldboard ploughing (CT), minimum tillage, ridge tillage and no-tillage (NT). In 1993, actual crop evapotranspiration was measured throughout the growing season on NT and CT soybean, using a micrometeorological technique.
No significant differences due to soil tillage were found for grain yield and yield irrigation water use efficiency (IWUEy), except for soybean in 1994, in which yields and IWUEy were 59 % higher on conservation tillage treatments compared with CT. In 1994 soybean yield water use efficiency was 10.1 and 9.5 kg ha−1 mm−1 for NT and CT respectively. The results suggest that the adoption of soil conservation tillage is feasible, for the specific cropping system, with equivalent or better performances as conventional tillage.  相似文献   

7.
摘 要:利用野外风洞设备,以翻耕地为对照,对科尔沁沙地东部农田的4种不同作物茬地抗风蚀效果进行了测试,对风蚀主要影响因子进行了分析。试验结果表明:作物留茬可显著提高地表抗风蚀能力;在相同风速条件下,抗风蚀能力大小依次为燕麦茬地>玉米茬地>向日葵茬地>绿豆茬地>翻耕地;与翻耕地相比,燕麦茬地、玉米茬地、向日葵茬地和绿豆茬地的起动风速分别抬高了53.3% 、17.8% 、11.1%、 8.9%。本试验表明,风蚀量与土壤地表覆盖度、土壤0~5cm表层含水量、地表粗糙度、土壤容重、土壤坚实度呈负相关关系,其中与前三者呈显著高度负相关关系。采用免耕留茬措施可以有效地抑制农田土壤风蚀,有利于防治农田荒漠化。  相似文献   

8.
Three different tillage practices, conventional (mouldboard ploughing at 22–25 cm plus one rotary hoeing at 5–6 cm, CT), minimum (one rotary hoeing at 12–15 cm, MT), and no‐tillage (direct drilling in soil covered by vetch residues, NT), combined with three fertilization treatments, inorganic (50 kg N ha?1 as ammonium sulphate), cattle manuring (30 t ha?1), and control (no‐fertilizer), were applied on a cotton crop (Gossypium hirsutum L. cv. Acala SJ‐2) grown on a clay loam soil in the field of the Agricultural University of Athens. Soil (gravimetric water content, bulk density, and penetration resistance in the top 40 cm) and plant parameters (root growth, leaf water potential, leaf area growth and seedcotton yield) were recorded throughout the cultivation period in all treatments. No‐tillage was associated with significantly higher values of soil water throughout the observation period caused by the vetch mulch. Bulk density and penetration resistance were initially higher in the no‐tilled plots, but they became significantly lower after 2–3 months from sowing. These beneficial effects on soil properties favoured root growth, expressed as root surface density, in the NT‐plots at the top soil layer. Similar, although less spectacular, effects were observed in the manured plots. Plant water status, expressed in terms of the water potential index, was significantly and consistently best in the NT‐ and worst in the CT‐plots throughout crop growth. In addition, NT favoured a better foliage growth and resulted in significantly higher yields than the other tillage practices. In general, NT, and in second instance, MT considerably improved plant water status, and hence foliage growth and yield in comparison with CT by maintaining higher levels of soil water and improving root growth. Manuring positively interacted with the reduced tillage practices for most soil and plant parameters.  相似文献   

9.
Abstract Estimates of soil evaporation and available soil water of no‐tillage fields under farm conditions are important to assess soil water status at sowing of rainfed grain crops. The objective of this study was to predict stored soil water of no‐tillage fields during the fallow periods following soybean (Glycine max (L.) Merr.) and maize (Zea mays L.) crops by accounting for decreased soil evaporation as a result of the residues left on the soil surface. Three simple phenomenological models were used to simulate stored soil water under field conditions at seven locations in Argentina. Two models calculated decreased soil evaporation based on crop residue mass, and the third assumed a constant fractional decrease in bare soil evaporation. All models gave good estimates of soil water content during the fallow periods following a soybean crop. In cases with large quantities of maize residue, however, the models resulted in more water retention in the soil than observed as a consequence of underprediction of soil evaporation. These results indicate that full benefit of crop residue was not being achieved in these fields, probably due to a failure to finely chop and uniformly distribute the crop material on the soil surface.  相似文献   

10.
为明确冬小麦―夏玉米轮作种植模式中,不同耕作整地方式对小麦播种质量、产量和效益的影响,设置旋耕2次、深松+旋耕、重耙+旋耕、翻耕+轻耙、翻耕+旋耕、重耙+翻耕+轻耙和重耙+翻耕+旋耕(CK)共7种耕整地方式。结果表明,在夏玉米为籽粒玉米的地块,7种耕作整地方式中CK处理的秸秆含量较少,地表及0~20cm土层平均秸秆含量较其他处理减少27.5%和28.6%,土壤与秸秆混合较均匀,0~20cm土层中每5cm土壤平均容重较其他处理变化减小30.5%,播种深度适宜,平均3.9cm,出苗质量好,缺苗断垄较其他处理降低25.7%,苗间离散度均匀,平均极差减小39.0%,穗数最多(670.5万/hm2)、产量最高(7966.5kg/hm2)、效益最高(9051.0元/hm2),与其他处理达显著性差异。在夏玉米为青贮玉米的地块,除旋耕2次和深松+旋耕的整地处理产量较低外,其余处理间产量差异不显著,其中翻耕+旋耕处理的产量和效益最高,分别为8133.0kg/hm2和9894.0元/hm2,效益显著高于其他处理。  相似文献   

11.
免耕的固碳效应研究进展   总被引:1,自引:0,他引:1  
免耕是一种保护性耕作,可显著地增强土壤的固碳能力。土壤有机碳的获得或者损失取决于生物或有机质剩余的碳增加量与作物收割、微生物化或者分解过程中的碳丢失量这二者的比率。农田耕地的废除恰好可以使作物残茬分解速率降低、土壤有机碳增加。而与土壤耕地有关的几个因素加速了残茬的分解。秸秆还田的手段通过微生物分解的方式提高了对损失碳的利用。免耕提高了农业可持续性能力和抵消人为因素的温室气体排放。总CO2释放量的50%发生在夏季。研究中CO2平均年释放数据表明NT释放量低于常规耕种系统,表层碳积累量明显高于常规耕种系统。除了提高土壤的固碳能力以外,免耕对土壤质量参数产生好的影响,改善了土壤结构,提高了土壤渗透率,减少了流失和侵蚀,这些提高很大程度上是土壤表层有机质积累的结果。文中指出,中国应加土壤固碳能力的研究,并适度的推广免耕政策。  相似文献   

12.
保护性耕作下农田土壤风蚀量及其影响因子的研究初报   总被引:1,自引:0,他引:1  
李琳 《中国农学通报》2009,25(15):0-214
本研究采用移动式风洞仪对北京市保护性耕作下农田土壤风蚀影响进行研究,并得出以下初步结论:(1)六种地块下土壤风蚀量以裸露翻旋地最高,种植越冬覆盖作物能显著降低土壤风蚀量;不同免耕播种机和秸秆处理方式下,风蚀量区别主要在于播种机,以迪尔风蚀量最低,农哈哈机型最高;四种耕作方式下土壤风蚀量以旋耕地最高,翻耕地比旋耕地降低80.81%,重耙和免耕地风蚀量分别比旋耕地降低95.35%和97.71%;冬小麦五种不同播期下土壤风蚀量随着播期的推后逐渐增大。(2)四种作物中小麦田的覆盖率最高,其次为紫花苜蓿和小黑麦,油菜覆盖率最低;四种耕作方式下耙耕小麦田覆盖率最高为84.00%,旋耕最低为55.33%;五个播期下9月27日播种的小麦田覆盖率显著高于其他播期,10月7日和10月12日最低。(3)将土壤风蚀量作为依变量,覆盖率、作物株高和土壤容重作为自变量进行多元回归分析,并建立多元回归方程:Y=173.186-0.449x1-0.485x2-72.699x3。  相似文献   

13.
Crop residue removal and subsoil compaction are limiting to yield improvement in the North China Plain (NCP). We conducted a field study composed of six consecutive crop growing seasons from 2010 to 2013 in Henan province, China, to determine responses of soil properties, crop root distribution and crop yield to tillage and residue management in a wheat–maize cropping system under irrigated conditions. Tillage practices comprised mouldboard ploughing (MP) to a depth of 15-cm, deep mouldboard ploughing (DMP) to a depth of 30-cm, and chisel ploughing (CP) to a depth of 30-cm. Crop residue management included crop residue retained (CRRet) and crop residue removed (CRRem). The results indicated that yields in DMP and CP increased by 6.0% and 7.3% for wheat and by 8.7% and 9.0% for maize, respectively, relative to MP. The CRRet treatment also increased wheat yield by 6.7% and maize yield by 5.0%. The yield increases under DMP and CP were related to reduced bulk density and soil penetration resistance, increased soil water content, improved total N distribution and improved root density (0–60-cm). Compared with MP, the root mass density under DMP and CP were increased by 43.4% and 42.0% for wheat and by 40.6% and 39.4% for maize, respectively. The yield increases under CRRet were also related to increased soil water content, reduced penetration resistance and increased N status (0–40-cm). Overall, for DMP + CRRet and CP + CRRet, a more favorable soil environment alongside greater root mass density and suitable spatial distribution resulted in higher grain yields of wheat and maize. Thus, compared with conventional shallow tillage practice, DMP or CP with residue application could improve soil quality and agricultural productivity under irrigated areas with loam soil in the NCP.  相似文献   

14.
Sustainable farming practices can be beneficial or detrimental to crop production in the short-term, which will strongly determine their appeal to farmers. We evaluated the effects of several sustainable practices on soil properties, plant nutrition and ecophysiology and crop yield in a semiarid agroecosystem. A three-year randomised experiment was conducted in a rainfed almond grove where the initial soil management was reduced tillage. Two alternative treatments were evaluated: reduced tillage plus green manure and no-tillage. The following soil and plant parameters were measured once per year: soil organic carbon, total nitrogen and Polsen; foliar N, P, δ13C and δ15N and crop yield. We found that soil bulk density increased significantly with no-tillage. Leaf δ15N was positively associated with soil fertility, foliar nutrient concentrations and crop yield across treatments. Leaf δ13C, Nfoliar and crop yield were strongly positively associated across treatments in every year of the study. Reduced tillage treatments displayed higher leaf δ15N, δ13C, Nfoliar and crop yield than the no-tillage treatment, indicating a sharp decrease in the leaf nitrogen status and intrinsic water use efficiency of almond trees during the transition from reduced tillage to no-tillage. In semiarid agroecosystems where soils are prone to compaction, some tillage is required to maintain optimal crop production in rainfed almonds.  相似文献   

15.
Due to the high cost of fuel and labour associated with conventional tillage, and because of their advantageous environmental consequences, interest in reduced and zero tillage systems has increased. Direct drilling into zero tilled (ZT) soil of two spring barley (Hordeum vulgare L.) cultivars (six-rowed Rolfi and two-rowed Saana), spring oats (Avena sativa L., cultivar Roope), and spring wheat (Triticum aestivum L., cultivar Kruunu) was compared with conventional tillage (CT) and drilling into ploughed soil. Two field experiments were conducted on clay soils (clay content > 50%) between latitudes 60° and 61° N. Seed and fertilizer were placed in the same row in ZT and in separate rows in CT. Oats was the most productive spring cereal species in ZT. Establishment of spring wheat was often poor. Barley was most vulnerable to water surplus during early growth and drought during late growth. High levels of crop residues caused problems in soil drying in spring and growth of monocultures of oats and wheat. A higher seeding rate was advantageous in zero tilled clay soil. The substantial grain yield decrease suggests need for improving ZT.Long-term trials are required to determine whether ZT suits clay soils as soil structure can change over time and weather conditions play a major role in the productivity of differently tilled soils.  相似文献   

16.
Effect of different tillage practices on soil structure and nitrogen dynamic in loess soils with and without longterm application of farmyard manure
Field trials were conducted in 1979 and 1980 on two farms with and without longterm application of farmyard manure respectively, to study the effect of different tillage practices (ploughing at low soil moisture in summer and autumn and ploughing at highsoil moisture in autumn) on soil structure and nitrogen dynamic. Soil structure measurements showed great differences between ploughing at low and high soil moisture contents. Ploughing soil at high moisture contents caused a rise in penetrometer resistance as in bulk density and a decrease of macropors as well as in oxygen concentration in top soil and in tillage pan. But little differences were observed between ploughing in summer and autumn at low soil moisture contents.
Ploughing soil at high moisture contents caused a higher soil compaction on the farm without longterm application of farmyard manure compared to the farm with longterm application of farmyard manure.
The differences in soil nitrate content were strongly correlated with soil compaction. Very large differences in soil nitrate content between ploughing at low and high soil moisture contents were always observed in May, when the soil temperature was higher than 15°C These differences in soil nitrate content are due to reduced nitrogen mineralization and an increase of denitrification activity after ploughing at high soil moisture contents.  相似文献   

17.
针对宁夏中部干旱带土壤风蚀严重、沙尘暴频发等生态问题,分别选择典型压砂农田、沙质旱作传统翻耕农田、人工灌木林地、封育草场和流动沙地5种风蚀环境为研究对象,利用TOPSIS法综合评价不同风蚀环境抗风蚀性能。结果表明:灌木林地的抗风蚀性能最强,其Ci值为0.674257,其次为压砂农田、封育草场;抗风蚀性能最弱的是翻耕农田、流动沙地,Ci值分别为0.087007和0.003552。可见翻耕农田和流动沙地是当地主要沙尘来源。  相似文献   

18.
土壤侵蚀是重要的环境公害,侵蚀造成土壤有机碳的大量迁移、转化和流失,产生严重的环境问题,相关机理研究尚不清楚。本文阐述了水蚀和风蚀两种主要方式对土壤有机碳库的影响,侵蚀和二氧化碳温室气体排放的关系。介绍了林地转为农田、草地以及草地转为农田等土地利用方式的改变对土壤有机碳库的影响,免耕提高土壤固碳能力。提出了控制侵蚀,减少土壤碳流失的措施。  相似文献   

19.
华北平原免耕冬小麦生长发育特征研究   总被引:20,自引:3,他引:17  
2004—2006年在河北栾城中国科学院农业生态试验站开展了不同耕作方式下冬小麦生长发育特征及其影响因素的比较研究。冬小麦基本苗数和分蘖率在不同耕作方式间差异显著, 表现为免耕<旋耕<翻耕。免耕处理冬小麦分蘖成穗率高于翻耕和免耕处理, 但基本苗数低, 2004—2005生长季比翻耕和旋耕处理分别低28.9%和29.7%, 2005—2006生长季分别低11.7%和10.0%; 免耕处理冬小麦株高、叶面积指数、地上部干物质积累和产量均低于翻耕和旋耕处理, 其中叶面积指数在2004—2005和2005—2006生长季的最高值分别为2.9和6.0, 产量比翻耕降低30.1%和27.19%、比旋耕降低15.3%和25.20%。免耕可保持耕层较高的土壤水分含量, 总体上高于翻耕和旋耕处理; 免耕处理在冬小麦苗期和返青期表现出明显的“降温效应”, 耕层土壤日均温度低于翻耕和旋耕, 冬小麦出苗和返青较翻耕和旋耕分别晚1~3 d和4~5 d。  相似文献   

20.
Mouldboard ploughing is known to accelerate soil organic matter (SOM) mineralization rate in Mediterranean regions. Long-term reduced tillage intensity potentially diminishes soil organic carbon (SOC) and total nitrogen (STN) depletions. Here, we compared long-term no-tillage (NT) and conventional tillage (CT) impact on SOC and STN sequestration rates at different depths ranging from 0 to 30 cm. The long-term experiment started in 1986 on a Typic Xerofluvent soil in Central Italy using a randomized complete block design with four replications. Ten years after the experiment began, SOC and STN concentrations in the 0–30 cm soil layer were already higher under NT compared to CT. The shallow layer (0–10 cm) showed the highest SOC and STN concentration increments. However, no differences between tillage systems were observed in the deeper layers. After 28 years, continuous NT increased SOC and STN content in the 30 cm soil depth by 22% compared to initial values. In the same period, continuous CT decreased SOC and STN content by 3% and 5%, respectively. On average, the total SOC and STN gains under NT may be attributed to the shallow layer increments. In the 10–20 and 20–30 cm soil layers, SOC accumulation over time was negligible also under NT. In the whole profile (0–30 cm), the mean annual SOC variation was +0.40 Mg ha−1 yr−1 and −0.06 Mg ha−1 yr−1 under NT and CT, respectively. Under NT, SOC content increased rapidly in the first ten years (+0.75 Mg ha−1yr−1); later on, SOC increments were slower indicating the reaching of a new equilibrium. Data show that NT is a useful alternative management practice increasing carbon sequestration and soil health in Mediterranean conditions.  相似文献   

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