38 research outputs found

    Analysis 0n Soil Fertility and Productivity of Hillside Fields in the First Sub-region of Loess Hilly Region

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    根据调查研究,分析了黄土丘陵第一副区山坡地土壤肥力与生产力状况及其影响因素,表明由于长期土壤侵蚀的影响,该区山坡地土壤的有机质、全氮和碱解氮含量低,虽然全磷和全钾含量相对较丰富,但其有效性不高,土壤水分条件差且多变,土壤肥力贫瘠。严重的水土流失、干旱和土壤肥力低下是导致该区山坡地生产力低下的主要因素,因此,采取水土保持耕作技术,控制水土流失和合理增加肥料投入是提高山坡地土壤肥力和生产力的重要途径

    The Soil Resources and Evaluation for the Soil Nutrient Level in Daliuta Township in Shefu Coal Field

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    本文概述了神府煤田在柳塔镇辖区内的土壤类型及其分布和土壤的基本理化性质。并应用模糊综合指数法对区内土壤养分状况进行评价,表明河谷川道区及部分沟底地土壤养分充足;而盖沙丘陵区的长期耕种和培肥的土壤养分充足,但是不便于培肥的农地土壤以及稀疏草地土壤养分缺乏。根据养分的测定值及养分的模糊综合评价结果,提出了培肥土壤和提高土壤有效养分途径

    Effects of Relief on Soil Nutrient Losses in Sloping Fieldsin Hilly Region of Loess Plateau

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    根据黄土丘陵区坡地径流小区试验,研究了次降雨条件下,坡地地形因素中的坡长及坡度与土壤养分流失的关系和土壤可溶性养分离子随径流液而流失的状况。初步结果表明,坡地土壤有机质及速效氮、磷、钾养分的流失强度与坡长呈指数函数关系(NL=a1·exp(b1x),a1>0,b1>0),养分流失强度随坡长的增加呈指数增加趋势;坡地土壤有机质的流失强度与坡度呈指数函数关系(NS=a2·exp(b2x),a2>0,b2>0)。径流液中的养分离子流失强度大小顺序为:钙离子>钾离子>无机氮(NO-3-N+NH+4-N)

    Effect of Amendment of Leaf and Stem of Switchgrass(Panicum virgatum)

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    采用室内恒温(25℃)培养的方法,研究施用不同用量的柳枝稷茎、叶对土壤有机碳(SOC)和微生物量碳(MBC)的影响,柳枝稷茎、叶在土壤中分解特性。结果表明:柳枝稷茎、叶施入土壤培养90d后,随着柳枝稷茎、叶施入量的增加,SOC和MBC含量明显增加。在柳枝稷茎、叶施用量相同的条件下,施入柳枝稷叶后,土壤微生物量碳的含量高于施用茎的含量,而施用叶的土壤中有机碳的含量低于施入茎的土壤有机碳的含量。柳枝稷茎、叶在土壤中的分解率具有一定的差异,且与施用量有关。在相同的柳枝稷茎、叶施用量条件下,叶在土壤中的分解率高于茎的分解率,表明了茎中的有机碳在土壤中周转期比叶中的长,说明施用柳枝稷的茎可以有效地促进土壤有机碳的累积Abstract:An incubation experiment under the constant temperature of 25℃ was conducted to investigate theeffect of amendment of leaf and stem of switchgrass(Panicum virgatum)on soil organic carbon(SOC)andmicrobial biomass carbon(MBC)and the decomposition characteristic of the leaf and stem at various amendment rates of switchgrass leaf and stem.The results showed that the contents of SOC and MBC increasedwith amendment rates of switchgrass leaf and stem after the incubation of 90days.Under the same amendment rates of leaf and stem,the pools of soil MBC were larger in the treatments of leaf amendment than thatin the treatments of stem amendment,whereas the contents of SOC were higher in the treatments of stem amendments than those in the treatments of leaf amendments.There was a certain discrepancy of decomposition rate between the leaf and stem.The decomposition rates of leaf and stem were determined by the amendment rates.Under the same amendment rates of leaf and stem,the decomposition rates of leaf were higherthose of stem,indicating that turnover rate of organic of stem in the soil was longer that of the leaf,and theamendment of stem was conductive to accumulation of organic carbon in soil

    Simulated Study on Movement Features of Soil Nitrogen in Different Forms in Soil Profile

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    应用室内土柱模拟试验方法 ,在可控水量条件下 ,研究不同水量淋溶情况下 ,土壤不同形态氮素在剖面中的分布和移动特征。研究表明 ,土壤有机氮组分中 ,氨基酸氮和 NH3- N是易于移动的形态 ,非酸解性氮则相对稳定 ;无机氮组分中 NO- 3 - N是易于移动的形态 ,NH+ 4 - N运移性差 ,非交换态 NH+ 4 - N为相对稳定形态 ;水、肥条件是决定 NO- 3 - N淋失的重要因素。研究结果为认识和掌握土壤氮素在剖面中的运移规律 ,为农田水分和氮素养分管理提供了科学依据 ;同时为深入揭示土壤中各种形态氮运移动态机制 ,展示了模拟实验技术的前

    长期施用化肥条件下土团聚体中有机碳与养分分布

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    [目的]探究长期施肥与小麦&mdash;玉米轮作下土表层水稳性团聚体组成及对团聚体中有机碳和养 分分布的影响,为评价长期施肥对改善土肥力状况的影响提供科学依据。[方法]利用田间长期施用化 肥与轮作定位试验,通过湿筛法分离土壤水稳性团聚体,得到土壤团聚体构成,并测定不同粒径团聚体中 有机碳和养分的含量。[结果]结果表明长期施用化肥显著影响土壤水稳性团聚体含量,长期施肥降低了 >2mm的水稳性团聚体数量,增加了<1mm的水稳性团聚体含量。施肥在一定程度上提高了水稳性团 聚体有机碳的含量,但施用高量氮、磷下0.25~0.5mm和<0.25mm水稳性团聚体中有机碳含量明显低 于施用低量氮、磷肥料。不同施肥处理土壤水稳性团聚体全氮含量变化趋势与水稳性团聚体有机碳含量 基本一致。磷素在不施肥处理各粒径团聚体中均匀分布,低氮、磷处理各粒径团聚体中全磷含量差异较 小,高氮、磷处理各粒径土壤团聚体中全磷含量变化无明显趋势。长期施肥降低了>2mm水稳性团聚体 中全K含量,增加了<2mm的水稳性团聚体中全K含量。[结论]水稳性团聚体关系土壤有机碳、氮的数 量,水稳性团聚体及其中有机碳、氮含量在氮磷化肥的长期施用下变化无明显规律,并且,长期施用氮、磷 化肥下土壤磷素和钾素在土壤中的保存及供应能力也受到影响。因此,需要合理施肥管理,促进农田生产 力的可持续发展。</p

    Organic carbon storage in the vegetation biomass in secondary forest region of Ziwuling Mountain

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    根据野外调查和观测,对子午岭次生林区的灌木和森林植被地上部各部分生物量中有机碳的储量进行了比较和分析。在灌木群落中,狼牙刺、虎榛子和沙棘群落中的茎杆与枝条中有机碳的储量分别占地上部生物量中有机碳储量的70.59%~75.33%、95%和83.84%;茎杆和枝条及叶片生物量中有机碳储量的顺序为沙棘&gt;狼牙刺&gt;虎榛子;灌木群落中草本层生物中有机碳储量的顺序为狼牙刺&gt;沙棘&gt;虎榛子;地被层有机物质中有机碳储量的顺序为沙棘&gt;虎榛子&gt;狼牙刺。狼牙刺群落、虎榛子群落和沙棘群落中有机碳的储量分别为15.06~16.25t/hm2、8.84t/hm2和25.67t/hm2。在森林植被中,山杨-辽东栎混交林、山杨林、白桦林、辽东栎林等落叶阔叶林的茎与枝条中有机碳的储量,占地上生物量中总储碳量的88.66%~97.75%、侧柏林和人工油松林针叶林的茎和枝条中有机碳的储量,约占地上生物量中总储碳量的83%,除过人工油松林外,乔木林中灌木层中有机碳储量的顺序为白桦&gt;山杨-辽东栎&gt;山杨&gt;侧柏&gt;辽东栎,乔木林中草本层生物量中有机碳的储量为0.5~0.6t/hm2,人工油松林的草本层生物量中有机碳的储量为1.26t/hm2,天然乔木林下地被物..

    Driving Effect of Alfalfa(Medicago sativa L.)on Dynamics of

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    根据旱地长期定位试验和分离土壤有机质中微粒有机质及矿物结合有机质的方法,研究了长期生长苜蓿对土壤有机碳、全氮变化的驱动作用。结果表明:不施肥条件下,苜蓿地土壤有机碳、全氮的含量比裸地土壤中的含量明显增加,土壤有机碳和氮库中的微粒有机碳、氮的含量没有显著增加,而增加的有机碳、氮主要分布在矿物结合有机碳、氮组分中。在施用有机肥及氮、磷化肥条件下,苜蓿地土壤有机碳和全氮的含量显著地提高,增加的有机碳、氮几乎平均地分布在微粒有机碳、氮和矿物结合有机碳、氮组分中。由此表明,保持适宜的苜蓿生产力并采用合理的施肥措施,长期生长苜蓿能够有效地驱动土壤固定有机碳和氮素,从而保持和提高土壤肥力。Land use has a significant impact on change in soil organic carbon and nitrogen.The driving effect of alfalfa(Medicago sativa L.)on the dynamics of soil organic carbon and nitrogen in dryland was studied based the long-termfield experiment and the method for separating the soil organic matter into particulate organic matter and mineral-associated organic matter.The level of soil organic carbon(SOC)and nitrogen in the land grown alfalfa withoutfertilization increased compare with the bare land,the particulate organic carbon(POC)did not demonstratesignificant changes whereas the mineral-associated organic carbon(MOC)and nitrogen increased.The statusof SOC and N in the land grown alfalfa applied manure and N and P fertilizers showed significant increasecompared with that in the land grown alfalfa without fertilizer,and the increased organic carbon and nitrogendistributed in the fraction of POC and MOC,respectively.These results suggest that applying the manureand chemical fertilizer in the alfalfa land and keeping the rational alfalfa productivity is the sustainable way tosequester organic carbon and nitrogen and to improve soil fertility in the semiarid area
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