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1.
本文对国内现行土壤速效养分速测方法进行了改进 ,包括 :饱和浸提液的制备、浸提剂的筛选、测定方法的改进等 .实验结果表明 :新方法与代表性土壤速效养分速测方法比较 ,提高了精度 ,省时 ,成本低 ,适合于基层土肥站和肥料厂开展测土施肥工作 .  相似文献   

2.
Abstract

The design, materials and dimensions for constructing a coring device for sampling soil fauna and flora at different depths is described.  相似文献   

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4.
丁宁宁  王保松  梁珍海  刘德辉 《土壤》2011,43(3):487-492
在大丰市麋鹿保护区内,设置滩涂荒地(A样区)、挖沟排盐结合耐盐植物初步改良(B样区)、挖深沟作垄结合耐盐植物多年改良(C样区)和在C样区改良基础上进行覆被种植再改良熟化(D样区)共4个试验样区,按0~20cm和20~40cm两层采集土壤,测定土壤pH和总盐分含量,分析、评价不同改良措施对苏北淤泥质滩涂土壤的改良熟化效应...  相似文献   

5.
Rapid soil testing and soil quality assessment are essential to address soil degradation and low farm incomes in smallholder farms. With the objective of testing diffuse reflectance spectroscopy (DRS) to rapidly assess soil chemical properties, nutrient content and a soil quality index (SQI), samples of surface soil were collected from 1113 smallholder farms in seven districts in Bundelkhand region of Uttar Pradesh, India. A minimum dataset (MDS) approach was followed to estimate SQI using the three chemical parameters of soil pH, electrical conductivity (EC) and soil organic carbon (SOC), and 11 different soil nutrients. Principal component and correlation analyses showed that soil pH, SOC content and three available nutrients − copper (Cu), iron (Fe) and sulphur (S) − may constitute the MDS. Estimated SQI values showed strong positive correlation with crop yields. Results of chemometric modelling showed that the DRS approach could yield the coefficient of determination (R2) values in the validation datasets ranging from 0.79 to 0.94 for exchangeable calcium (Ca) followed by 0.67–0.88 for exchangeable potassium (K), 0.52–0.86 for SOC and 0.53–0.81 for available boron (B) content. Except in one district, the DRS approach could be used to estimate SQI values with R2 values in the range of 0.63–0.81; an R2 value of 0.71 was obtained in the pooled dataset. We also estimated the three-tier soil test crop response (STCR) ratings to compare DRS and wet chemistry soil testing approaches. Similar STCR ratings were obtained for both these approaches in more than 86% of the samples. Parameters for which both the methods yielded similar ratings in more than 80% of the samples were EC (>98%), pH and exchangeable Ca (>81%) and available B (>89%). With similar ratings, these results suggest that the DRS approach may safely be used for farmers' fields, replacing the traditional wet analysis approach of soil testing.  相似文献   

6.
为进一步完善我国水土保持农业技术措施的分类体系,并服务于研究与生产,在论述水土保持农业技术措施的概念、分类现状基础上,依据措施实施的方式、作用和目标,并结合农艺环节,将水土保持农业技术划分为以改变微地形为主的蓄水保墒技术、以提高土壤抗蚀力为主的保护性耕作技术和以增加植物覆盖为主的栽培技术3大类,等高耕作、沟垄种植、坑田、半旱式耕作、深耕翻、保墒、覆盖、深松、少耕、培肥土壤、合理配置作物、播种保苗、栽培13个亚类和等高耕作等44个型,以供参考.  相似文献   

7.
黄土高原水土保持措施对侵蚀土壤发育的效应   总被引:1,自引:0,他引:1       下载免费PDF全文
 水土保持工程及植被措施实施,对土壤形成条件、土壤特征及土壤发育产生一定影响,而侵蚀土壤发育程度是评价土壤质量变化及其生态环境效应的重要基础。研究黄土高原水土保持措施对侵蚀土壤理化性质、发育和功能的影响,可为水土保持综合治理,改善黄土高原生态环境提供依据。评述长期定位试验的方法及以空间代替时间的原理,研究了在实施不同水土保持措施后,土壤基本理化性状的变化特征。结果表明:随着措施实施年限的增加,土壤的水分环境和土壤有机碳含量发生了明显改善,对土壤结构和功能产生了影响。证明水土保持措施对侵蚀土壤的发育有一定促进作用。  相似文献   

8.
Abstract

The construction, theory and many of the factors such as interfering anions, extracting agents, soil to solution ratio, reference electrodes, accuracy and precision of the nitrate ion selective electrode are discussed in relation to routine soil testing for nitrate nitrogen.  相似文献   

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为评价北京山区多年来小流域综合治理的水土保持效果,也为以后小流域治理和植被重建提供理论支撑,以房山区蒲洼小流域为研究地,采用典型样地调查、野外抗冲性实验和室内样品处理的方法,对比分析不同水土保持措施的土壤物理性质、土壤质地和抗冲性.结果表明:随着土层加深,各类措施下土壤密度均呈现增大趋势,总孔隙度和毛管孔隙度呈现减小趋势,而非毛管孔隙度没有明显规律.不同水土保持措施下,土壤密度、总孔隙度和毛管孔隙度均有改善(侧柏林除外),改善程度由好到差依次为:辽东栎次生林>油松落叶松混交林>石坎梯田>油松林>落叶松林>灌丛;各类措施下土壤颗粒均以细、中粉粒为最多,分形维数显示各类水保措施土壤通透性均较为良好;相比荒地,各类措施下土壤冲刷量显著减小,径流时间延长,冲刷量依次为油松落叶松混交林(0.82 kg/cm3)<侧柏林(1.14 kg/cm3)<落叶松林(1.30 kg/cm3)<辽东栎次生林(3.91 kg/cm3)<油松林(5.96 kg/cm3)<荆条灌丛(10.88 kg/cm3),延缓径流冲刷时间由大到小依次为:辽东栎次生林(55.65 s/m)>油松落叶松混交林(46.82 s/m)>落叶松(28.19 s/m)>荆条灌丛(22.39s/m)>侧柏林(17.48 s/m)>油松林(16.94 s/m).土壤抗冲性与细、中粉粒体积分数(正相关)、非毛管孔隙度呈显著(负相关)关系最为密切,由此推出大根径的根系穿插形成的非毛管孔隙对土壤抗冲性是负效应.综上,油松落叶松林混交林提升土壤蓄水持水性能、土壤抗冲性均显示出很大的优势;石坎梯田效果也较好,是小流域治理应首先考虑的2类措施.  相似文献   

11.
用ASI法测定了土壤有效磷、有效钾和铵态氮,并与我国常规分析方法进行了相关性研究。结果表明:(1)ASI—P与Olsen—P呈极显著正相关,其相关系数在水作条件下比旱作条件下高,在酸性条件下比中、碱性条件下高,随着土壤pH值升高,两者的相关系数迅速降低;(2)ASI—K与NH4OAc—K呈极显著正相关,其相关系数在旱作条件下比水作条件下高,在碱性条件下比中、酸性条件下高,且对pH值和水分条件的变化均较敏感;(3)ASI—N比碱解N低得多,且在水作条件的中、酸性pH范围相关性较好。  相似文献   

12.
This paper examines the potential for extension providers to identify learning opportunities by intentionally surveying farmers attending soil testing workshops designed to improve soil health and its management. In south‐eastern Australia, regional government agencies have been running soil health workshops since 2014, yet they have rarely surveyed the participants to understand their previous experience or learning needs, and how that may inform their design. The workshop consisted of two sessions, separated by 6 weeks. Farmers at the first Session were told how to undertake soil measurements. At the second Session, they then discussed their soil test results. The workshop participants (n = 87) at four different localities in the Northern Tablelands of New South Wales were surveyed (68% response rate) at each session. Firstly, to examine their prior knowledge and experience of soil testing, and secondly on how they applied what they had learnt, examine if the soil test results matched their expectations, and their influence in land management decisions. The survey revealed to regional government agencies that the majority of survey respondents (62%) would soil test again. Despite more than half of the respondents infrequently or never having their soil tested, prior to the workshop, 50% indicated that the test results were unexpected. The motivation for those farmers who would soil test again was the specific desire to identify their soil's potential for improved production. The survey provided a way of profiling the workshop audience and obtaining important feedback on how to improve the impact of the workshops for participants.  相似文献   

13.
Background and Scope  Information on a potential contamination of soils or soil materials are derived by chemical analysis which takes place specifically for a given substance. For a comprehensive assessment, information on the bioavailable and mobile contaminant fraction, including all metabolites, is desirable. During the last years several research projects were initiated in Germany, to supplement the chemical analyses and to elaborate a suitable testing strategy. The main goal of this contribution is to elucidate the results of these research projects and to summarize the test strategy, which is recommended based on these results. Results and Conclusion  Ecotoxicological tests, which are standardized for the assessment of chemicals, were regarded as a suitable starting basis for a cost effective, pragmatic approach. Aquatic tests (testing of aqueous soil extracts) focus on the retention function of soils and terrestrial tests (testing of soil) on the habitat function. Suitable reference systems for the terrestrial tests and assessment criteria for both test types (terrestrial and aquatic) were elaborated. On the basis of a round robin test and a laboratory comparison test, a minimal test battery was established. This minimal test battery can be supplemented by further tests if more or specific information is required. Outlook  The recommendations should encourage the discussion regarding the application of biological methods for the assessment of soil quality. Such an assessment is or at least can be required by soil protection laws which have been adopted in some European countries within the last years.  相似文献   

14.
紫色土丘陵区典型水土保持措施的适宜性评价   总被引:4,自引:0,他引:4       下载免费PDF全文
为科学合理选择适宜的水土保持措施,利用特尔斐(Delphi)法和模糊数学原理,对紫色土丘陵区典型水土保持措施进行区域适宜性评价。以问卷调查为基础进行评价指标的筛选,从求-供和产-望2个角度建立2套评价指标体系。根据评价指标与水土保持措施适宜性之间的关系选择单项指标评价模型,采用特尔斐法确定各评价指标的权重,最后结合加权求和与几何平均方法对水土保持措施适宜性进行综合评价,并以四川省遂宁市群力村为例进行实证研究。结果表明:研究专家注重措施的水土保持效益和自然环境效益,当地农民则看重措施实施后的社会经济效益;在群力村较为普遍的4种水土保持措施中,退耕还草最为适宜,其次为退耕还林,等高耕作和梯田的适宜性相对较小,与实际推广情况一致;梯田和等高耕作的适宜性较低主要受到农村劳动力数量、农民投资能力和措施社会经济效益的限制。  相似文献   

15.
水土保持措施对板栗林土壤呼吸的影响   总被引:3,自引:0,他引:3  
为阐明板栗林土壤呼吸对水土保持措施的响应,采用IRGA法,对不同类型板栗林的土壤呼吸从2009年3月至2010年9月开展为期1年半的定位观测。结果表明:1)采取水土保持措施后,样地的土壤水分状况得到一定程度的改善,尤其随着采取水土保持措施年限的延长,其对土壤水分时空分布影响更为显著。2)4个板栗林样地的土壤呼吸速率均呈明显的单峰曲线变化,水土保持措施对土壤呼吸的季节动态无明显影响。3)样地Ⅰ和Ⅲ的参考呼吸R10分别为1.718和1.595μmol/(m2.s);而采取水土保持措施后,样地Ⅱ和Ⅳ的R10均表现为一定程度的降低,分别为1.092和1.324μmol/(m2.s)。样地Ⅰ和Ⅲ的土壤呼吸的温度敏感性指数Q10分别为1.927和1.899;采取水土保持措施后,样地Ⅱ和Ⅳ的Q10均表现为略微增加。采取水土保持措施后,土壤温度和土壤湿度对土壤呼吸速率的影响有一定程度的增强。研究结果可为把水土保持措施作为土壤严重侵蚀地区一种潜在的固碳减排模式提供基础数据。  相似文献   

16.
Abstract

Soil texture often plays an important role in the interpretation of soil analytical data for fertilizer advisory purposes. A reliable and inexpensive method of clay content estimation is, therefore, a requirement of most advisory laboratories. This note discusses the use of sample density (i.e. the mass of a scooped volume of soil) as an index of clay content. A strong relationship was found to exist between sample density and clay content, and such estimates of clay content were superior to those obtained by experienced pedologists using the “finger test” procedure. The use of this quick and simple procedure is considered to be ideally suited to soil testing laboratories handling large numbers of samples.  相似文献   

17.
概述了在农业领域中应用离子交换树脂获取土壤养分含量的研究进展,探讨了树脂的预处理方法、使用形式以及提取土壤养分的基本操作和影响因素,同时提出该技术在提取土壤养分中的应用前景及需要解决的问题。  相似文献   

18.
 为加速黄土高原水土流失治理的健康发展,在深入分析黄土高原水土流失治理存在的主要问题,以及生物措施治理黄土高原水土流失作用的基础上,按照黄土高原河谷平原区、黄土丘陵沟壑区、黄土高原沟壑区、鄂尔多斯高原区和土石山区5个类型区,提出以植被建设和保护为核心的生态建设思路和治理对策,同时指出了采取生物措施治理水土流失时需注意的若干问题。  相似文献   

19.
Abstract

Soil samples were obtained at 0–3, 3–6, 6–9 and 0–9 inch depths from experimental plots receiving five tillage treatments. Each of two samplers composited approximately six one‐inch cores from each plot. Soil samples were analyzed for acidity, P and K using routine analysis procedures in the University of Illinois Soil Testing Laboratory.

Few significant differences were attributed to sampler and it was concluded that samplers using similar sampling techniques were obtaining soil samples from the same population.

No significant differences in soil acidity at different depths were observed. The different tillage methods did significantly affect soil P at the 0–3 inch depth, but had no significant effect on soil P at deeper depths. Different tillage methods also significantly affected soil K values at different depths.  相似文献   

20.
Abstract

Experiments were conducted to seek a better basis for soil testing of rice paddy soils. Soils were incubated under variable conditions of simulated flooding, and then extracted with DTPA5 . The amounts of Cu, Zn, Mn and Fe extracted were sensitive to the imposed soil conditions. Good correlations between Zn extracted from simulated flooded soils and Zn uptakes by rice from flooded soils in pots, suggest that this approach to soil testing may be more useful for paddy soils than existing tests on air dried soils.  相似文献   

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