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1.
用多种数学统计方法对影响苹果活跃根生长发育的土镶理化因子进行了综合分析。结果表明：土壤有机质、含水量、土壤质地是影响根系生长发育的重要因子，有机质最为重要；同时，Ｃｕ、Ｂ和Ｆｅ３种微量元素也对根系的生长发育有重要作用；在土壤物理因子中，当物理性粘粒含量为２９．５％、石砾度为２９．３％时，最适合根系的生长发育；当土壤孔隙度为３９．９％、容重为１．４４ｇ·ｃｍ－３时，最不适于根系的生长发育。）和土壤孔隙度（ｒ＝０．５４４５＊），其次为土壤石砾度（ｒ＝０．４２６４）和水解Ｎ（ｒ＝０．４１５４）（均为１０％显著水平），与土壤全Ｎ、含水量、有效Ｃａ、Ｃｕ、Ｍｇ含量和ｐＨ值也有一定的正相关；与活跃根量呈负相关的因子有容量、物理性粘粒（即土壤质地）、有效Ｂ和Ｆｅ，但均未达到１０％以上显著水平；其它因子与活跃根的相关性甚小。２．２土壤理化因子对活跃根量影响的通径分析通径分析结果表明，土壤有机质的直接作用最大，其直接通径系数为１．８８３３，表明其含量每增加一个标准单位，就可以便根量增加１．８８３３个标准单位。在所有因子中，对根系影响最大的因子为有机质、含水量、Ｃｕ和物理性粘粒（土壤质地），其系数（绝对值）均在１．０以上，其? 相似文献
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采用盆栽试验方式，研究玉米秸秆对次生盐渍化土壤微生物、土壤理化性状及番茄生长的影响。结果表明：添加玉米秸秆丰富了盐渍化土壤中微生物数量，盐渍化土壤微生物群落中细菌有效序列数量增多，菌群结构趋于丰富化，主要影响的菌群为肠杆菌科（Enterobacteriaceae）、鞘脂单胞菌科（Sphingomonadaceae）和黄单胞菌科（Xanthomonadaceae）。添加玉米秸秆可以改善盐渍化土壤的团聚体结构，显著提高土壤有机质含量；同时加快了设施土壤中矿质元素的释放，碱解氮、速效钾、速效磷含量均降低。添加玉米秸秆处理的番茄株高、茎粗、光合指标均明显高于对照，产量也显著增加。 相似文献
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不同连作苹果园土壤酶活性及微生物状况的调查研究 总被引：9，自引：0，他引：9
通过对山东省栖霞市不同连作苹果园的土壤养分、土壤酶活性、土壤微生物数量调查发现：连作苹果园土壤的养分含量有所下降；土壤脲酶、中性磷酸酶、转化酶的活性下降；土壤中细菌数量大大减少，真菌的数量明显增多。轮作花生、玉米的果园和新果园土壤的养分、酶的活性和微生物的状况均好于连作果园。 相似文献
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铜梁县境内灰棕黄紫泥土占中性紫色土面积的30％以上，弄清该类土壤理化性状、养分含量状况、化肥利用率，施肥种类、数量和搭配比例与玉米产量之间的关系，从以前的定性化向定量化方向开展研究，具有重要的现实意义。通过试验综合分析表明，灰棕黄紫泥土中等肥力水平田块，以667m^2施N15～20kg，P2O54．8kg，K2O2．4姆为最佳产量和最佳经济效益配肥方案。合理施用氮肥是提高玉米产量的主导因素。在施用有机肥的基础上，氮、磷、钾肥合理搭配对提高玉米产量具有明显效果。 相似文献
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以连作7a的黄瓜试验田为研究对象,通过黄瓜-玉米轮作为栽培模式,设置后茬玉米不同种植密度和不同生长期处理,研究设施黄瓜连作土壤理化性质、酶活性及土壤微生物种群的变化。结果表明:后茬玉米种植密度为4 000株/667m2时,生长成熟模式与对照休闲处理相比较,土壤容重、EC值和有机质、速效氮、速效磷、速效钾含量降低,pH值升高;土壤脲酶、过氧化氢酶活性升高,蔗糖酶和磷酸酶活性降低;土壤微生物结构改变,细菌和放线菌数量上升,真菌数量下降。黄瓜-玉米轮作模式对设施连作土壤性状的改善具有显著效果。 相似文献
6.
不同间作模式对设施黄瓜生长及土壤环境的影响 总被引：6，自引：2，他引：4
采用小麦、大豆、燕麦为伴生作物与黄瓜间作，研究其对黄瓜生长发育及土壤环境的影响。结果表明：3种间作处理均使土壤容重显著降低，土壤总孔隙度显著提高；整个生育期内各间作处理均显著降低了土壤盐分积累，生育后期黄瓜—小麦处理的土壤EC值下降幅度最大，比对照下降38.96 %；黄瓜—小麦和黄瓜—燕麦处理的土壤有机质含量显著高于对照；各间作处理明显改善了土壤微生物的区系组成，使细菌和放线菌数量增加，土传病菌数量降低，以黄瓜—小麦处理最明显，尖孢镰刀菌3个时期的平均数量比对照下降了69.44 %；各间作处理明显促进了黄瓜生长和产量的提高。黄瓜—小麦间作的综合效果最好，达到了缓解设施土壤连作障碍的目的。 相似文献
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以2005—2021年发表的84例连作试验中的926组数据为研究对象，采用Meta分析方法，研究了连作障碍对农田土壤微生物的影响，以期为解决农田土壤的连作障碍提供参考依据。结果表明：连作障碍提高了土壤真菌数量(28.20%),降低了土壤细菌数量(19.85%)、放线菌数量(16.05%)及微生物Shannon指数(6.01%);与耐连作和不耐连作作物相比，忌连作作物连作显著降低了土壤细菌(25.10%)和放线菌数量(26.86%);连作年限与连作农田土壤中细菌和放线菌数量的变化趋势呈显著负相关(P<0.05);在年均温度和降雨量不同的地区，连作都会导致微生物多样性的变化。连作障碍导致土壤微生物群落发生显著变化，作物类型和连作年限是主要的影响因素。 相似文献
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为了解不同土地利用方式对冀西北坝上地区土壤化学性质的影响,对该地区4种土地利用方式(围封林地、围封采伐地、未围封林地和耕地)下的土壤化学性质进行了分析.结果 表明:耕地的pH在7.5～8.5之间,明显高于其他3种土地利用方式(在6.5～7.5之间)(P＜0.05);耕地土壤的有机质、全氮、全磷、全钾及速效氮、磷、钾都明显高于3种林地(P＜0.05);2种封育林地表层土壤(0～10 cm)各养分含量明显高于未封育林地(P＜0.05),但深层土壤差异不明显.土地利用方式对土壤养分的垂直分布有显著影响,耕地土壤养分,除速效磷外,均表现为先下降后上升的趋势,养分含量变化曲线呈"V"型;3种林地土壤养分随土层深度的增加而降低,拐点均在10～20 cm土层,养分含量变化曲线呈"L"型.由以上结果得出结论,土地利用方式对土壤养分含量及其空间分布具有明显影响,耕地因为人工施肥的原因各养分含量明显高于林地,但土壤有明显的盐碱化趋势;封育可明显提高林地表层土壤养分含量,但对深层土壤影响较小. 相似文献
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为了解塞罕坝地区不同植被地表土壤动物群落特征,分别以白桦林、阔叶混交林、落叶松林、针阔混交林、云杉林、草甸为研究对象,于2017年7月采用陷阱法采集不同植被土壤动物并对其群落组成、结构及多样性进行分析。结果显示,6种植被样地中共获得土壤动物8 351头,隶属5纲19目96科186种,优势类群为盲蛛目、弹尾目、膜翅目、鞘翅目和双翅目。白桦林、落叶松林、阔叶混交林和针阔混交林土壤动物类群数均显著高于草甸和云杉林;落叶松林土壤动物个体数显著高于其他林分。各植被类型之间土壤动物Shannon-Wiener多样性指数和均匀度指数无显著差异。主成分分析和相关分析显示不同植被地表土壤动物的空间分布差异显著,且土壤动物个体数与林分内凋落物生物量、厚度、全氮、全磷、全碳含量及土壤容重呈极显著正相关。可见,塞罕坝地区不同植被类地表土壤动物群落组成和分布存在一定差异,地表环境因子是影响其组成的重要因素。 相似文献
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为了解决长期施用化肥导致盐化潮土质量和甜菜品质下降的问题,研究了牛粪、油菜籽饼、玉米秸秆和食用菌渣对河西内陆灌区盐化潮土性质及甜菜含糖率和效益的影响。结果表明:与化肥(CK2)比较,牛粪有利于降低盐化潮土容重,增加孔隙度和团聚体,容重降低8.82%,总孔隙度和团聚体分别增加4.53和8.28个百分点;玉米秸秆有利于提高盐化潮土有机质及阳离子交换量(CEC)和酶活性,有机质、CEC及蔗糖酶、脲酶、磷酸酶和多酚氧化酶活性分别增加36.93%、36.98%、17.69%、60.66%、23.75%和42.55%;食用菌渣有利于降低pH值,降低了5.85%;牛粪、玉米秸秆可显著降低全盐含量,分别降低了6.52%、5.80%;油菜籽饼有利于提高甜菜植株长势、产量、含糖率和经济效益,叶丛高度、单株鲜叶质量、根体长度、根直径、单株根质量和根产量分别增加16.28%、12.96%、13.00%、10.01%、8.42%和5.02%,含糖率提高1.35个百分点,施肥利润增加1 620.54元/hm2。施用有机物料改善了盐化潮土理化性质,提高了甜菜含糖率和经济效益。 相似文献
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猴头菌醋糟高产配方筛选及营养利用规律研究 总被引：7，自引：0，他引：7
本研究运用五元二次正交旋转回归组合设计进行了糟栽培猴头菌高产配方的初步筛选，并对猴头菌生育期间营养利用规律及酶活变化规律进行了探讨。结果表明，醋糟配料中的麸皮，黄豆粉和过磷酸钙与配料中的其它辅料通过互作产生了增产效应。经优化筛选，获得醋糟栽培猴头菌的两种高产配方：（1）醋糟44．12％，锯末25％，麦麸20％，玉米粉0．63％，黄豆粉5％，过磷酸钙2．25％，石膏2％，白糖1％；（2）醋糟43．50％，锯末30％，麦麸11．25％，玉米粉5％，黄豆粉5％，过磷酸钙2．25％，石膏2％，白糖1％。猴头菌菌丝生长阶段主要降解木质素，而子实体生长阶段主要降解纤维素和半纤维素，且漆酶，愈创木酚氧化酶，纤维素酶，半纤维素酶酶活性的变化与木质素，纤维素及半纤维素的降解规律一致。 相似文献
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Carol A. Johnston 《Landscape Ecology》2014,29(1):81-95
Land area planted to row crops has expanded globally with increased demand for food and biofuels. Agricultural expansion in the Dakota Prairie Pothole Region (DPPR), USA affects a variety of agricultural and non-agricultural land-use types, including grasslands and wetlands that provide critical wildlife habitat and other ecosystem services. The purpose of this study was to quantify recent changes in rural land cover/land use, analyze trends, and interpret results in relation to climate, agronomic practice, and ethanol production. The primary data sources were 1980–2012 statewide cropland data from the U.S. Department of Agriculture (USDA) National Agricultural Statistics Service, and the USDA Cropland Data Layer, produced annually for the DPPR from 2006 through 2012. Area planted to corn or soybean row crops increased, and small grain (e.g., wheat, barley) area decreased significantly over the analysis period. Corn and soybean expanded by 27 % in the DPPR between 2010 and 2012 alone, an areal increase (+15,400 km2) larger than the U.S. state of Connecticut. This expansion displaced primarily small grains and grassland (e.g., pastures, haylands, remnant prairies). Grassland regularly exchanged land with corn and soybean, small grains, and wetlands and water. Corn and soybean had high inter-annual self-replacement values (68–80 %), and continuous corn/soy row cropping was the second most common combination over a three-year period, ranking after continuous grassland. Small grain self-replacement values were only 22–35 %, indicating frequent relocation in the landscape. Temporary gains in wetland and grassland area were attributed to unusually wet climatic conditions and late snowfalls that prevented crop planting. Nearly all of the region’s ethanol refineries were located where corn and soybean crops constituted 50 % or more of the land area. Quantification of grassland losses in the U.S. Northern Plains requires evaluation of all land uses that interact with grasslands, and a longer term perspective that incorporates grassland as part of a normal land-use rotation. 相似文献
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羊肚菌菌种基质的研究 总被引：2，自引：0，他引：2
研究了二种羊肚菌菌株在四种培养基及五种培养料上的菌丝生长情况，结果表明，母种采用黄豆芽玉米粉培养基，栽培种采用棉籽壳木屑麦麸培养料，可缩短制种周期，获得质量较高的菌种。 相似文献
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Bradley J. Cosentino Robert L. Schooley Christopher A. Phillips 《Landscape Ecology》2011,26(3):371-379
Knowledge of how habitat heterogeneity affects dispersal is critical for conserving connectivity in current and changing landscapes.
However, we generally lack an understanding of how dispersal costs and animal movements vary among crops characteristic of
agroecosystems. We hypothesized that a physiological constraint, desiccation risk, influences movement behavior among crops
and other matrix habitats (corn, soybean, forest, prairie) in Ambystoma tigrinum (tiger salamander) in Illinois, USA. In a desiccation experiment, salamanders were added to enclosures in four replicate
plots of each matrix habitat, and water loss was measured every 12 h for 48 h. Changes in water loss were examined using a
linear mixed model. Water loss varied among treatments, over time, and there was a significant treatment-time interaction.
Water loss was greater in corn and prairie than in forest and soybean. To assess whether salamanders move through matrix habitats
that minimize desiccation, we tracked movements of individuals released on edges between habitats for two treatment combinations:
soybean–corn, and soybean–prairie. As predicted based on our desiccation experiment, movements were oriented towards soybean
in both cases. Thus, variation in desiccation risk among matrix habitats likely influenced movement decisions by salamanders,
although other factors such as predation risk could have contributed to habitat choice. We argue that conceptualizing dispersal
cost as uniformly high in all crop types is too simplistic. Estimating crop-specific dispersal costs and movement patterns
may be necessary for constructing effective measures of landscape connectivity in agroecosystems. 相似文献
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近年来，随着白洋淀内源污染与点源污染逐渐得到控制，农业面源污染逐渐成为制约白洋淀水质改善的重要因素。改善白洋淀生态环境状况，加强农业面源污染防控至关重要。然而，当前对雄安新区农业面源污染的认识尚待提高，尤其需要加强对种植业化肥使用及其氮磷盈余空间分布特征研究。因此，本研究以雄安新区主要种植模式小麦—玉米为研究对象，采用农田养分平衡方法，分析2016年雄安新区小麦—玉米氮、磷养分输入、输出与盈余情况，为雄安新区农业面源污染防控提供科学依据。结果表明：(1)雄安新区农田氮磷养分的输入以化肥为主，输出以籽粒为主，总体化肥氮、磷投入水平为446.82 kg/hm2、84.23 kg/hm2,籽粒输出氮、磷养分水平为312.71 kg/hm2、42.79 kg/hm2;(2)雄安新区小麦—玉米农田氮磷养分均表现为盈余状况，且氮磷养分盈余与氮肥、磷肥投入极显著正相关；(3)雄安新区氮素、磷素盈余强度分别为273.74 kg/hm2、44.99 kg/hm2,不同县市氮磷养分盈余量从高到低为安新县>雄县>容城县。建议进行合理的农田养分管理，开展养分平衡长期观测，实现化肥减量增效。 相似文献
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Soil Phosphorus Variability: Scale-dependence in an Urbanizing Agricultural Landscape 总被引：1，自引：0，他引：1
We examine the hypothesis that human activity changes patterns of variance in soil P (Bray-1) concentrations across several
spatial scales. We measured soil P concentrations and variability for each of four different land uses at three distinct levels
of analysis. Land uses were remnant prairie, lawns, corn fields of cash grain farms, and corn fields of dairies in Dane County,
Wisconsin (USA). For each land use type, levels of analysis were sites (an agricultural field, residential lawn or prairie,
ranging in size from 100 m2 to approximately 20 ha), 10-m plots within a site, and points within the 10-m diameter plot. The rank of mean soil P concentrations
was cash grain > dairy > lawn > prairie. For all land use types, most of the variance was accounted for by site-to-site variation.
Among-site variance was higher for human-dominated sites (0.55, 0.15, 0.14 [log (mg/kg)]2 for cash grain, dairy, and lawn sites, respectively) than it was for prairies (0.07 [log (mg/kg)]2). However, prairies had the highest among-plot variation (0.04 [log (mg/kg)]2) compared to other sites (0.01, 0.002, and 0.01 [log (mg/kg)]2 for cash grain, dairy, and lawn sites, respectively). The results indicate that in this watershed, human activity has increased
the mean soil P and variance of soil P, and shifted the scale of variance to larger spatial extents. Human impacts on landscape
pattern extend to soil properties that affect nutrient flow and eutrophication of surface waters. Because soil P turns over
slowly, the legacy of altered soil P patterns may affect freshwaters for centuries. 相似文献