Developing scoring functions for soil quality to assess land suitability for irrigated wheat in Southern Algeria     

Adil Mihoub  Naima Koull  Samia Helimi  Mohammed Elhafed Kherraze  Sakher Mokhtari  Manuel Pulido Fernández 《Soil Use and Management》2022,38(1):262-276

Efficient land-use management could be optimized through appropriate advice regarding land suitability and achieving a reasonable yield while preserving soil and environmental conditions. The main objective of this study was to determine and define those locations capable of wheat cultivation with irrigation in the municipality of N’goussa (Southern Algeria). Expert opinion (EO) method was used for selecting minimum soil data set (MDS_-EO), where six influencing soil properties (sand, pH, salinity, organic matter, gypsum and lime) and other three key parameters (slope, land use/land cover, and proximity to roads and electricity network) were considered important for irrigated wheat cultivation in the study area. Indicators were weighted according to principal component analysis (PCA) loadings and summed. PCA revealed that the selected nine indicators are appropriate for accounting 73.63% of the total variance. Two maps of land suitability were created here (expressed as a soil quality index within a range from 0 to 1) from multivariate analysis and already known standard scoring functions (SSFs) by using two data sets (pure and scored). The distribution of soil quality index (IQI) showed that above 70% of the land was moderately (MS) to highly suitable (HS) for irrigated wheat. The estimation accuracy of soil quality classes has been evaluated using random forests (RF), having as a dependent variable the final class of land suitability used in each map. It was determined that estimation accuracy could reach 60% (pure data set) and 65% (scored data set) at 0.5 cut-off value for soil quality classes. Final prioritizing according to ranks of sensitivity index (SI) and efficiency ratio (ER) showed that IQI obtained from scored data set is the most suitable approach in soil quality assessment of arid areas. Therefore, it could be applied in southern Algeria for land management, integrated planning and environmental assessments.  相似文献   

Ash and biochar amendment of coarse sandy soil for growing crops under drought conditions     

Esben W. Bruun  Dorette Müller-Stöver  Betina Nørgaard Pedersen  Line Vinther Hansen  Carsten Tilbæk Petersen 《Soil Use and Management》2022,38(2):1280-1292

Appropriate soil amendments may increase plant available water and crop yields on coarse sandy soils under drought conditions. In this study, we applied straw ash or straw biochar from gasification to a Danish coarse sandy subsoil to assess the effects on soil water retention, evapotranspiration and crop yields. Spring barley (2016, 2017) and winter wheat (2018) were grown over three years in columns containing 25cm of organic matter-rich topsoil, 80 cm of amended coarse sandy soil (1.5%, 3%, 6% wt. ash or 1% wt. biochar or control soil) and 45 cm of un-amended subsoil. Precipitation, evaporative demands and soil moisture were recorded across the growth seasons, with 2018 having severe drought conditions. This year evapotranspiration levels increased with increasing ash and biochar content (by 54% and 33% for the 6% ash- and 1% biochar-amended soils, respectively), and plant dry matter increased by 18% in both the 1% biochar- and 6% ash-treated soils compared to the untreated control. A linear relationship was established between in situ field capacity and ash dosage (R² = .96), showing an increase of 2.2% per percentage (wt.) of ash added, while the 1% biochar treatment increased the capacity by 3.5%, indicating a higher efficiency than for ash. However, we did not find significant positive effects on grain yields. The results show that ash and biochar have the potential to significantly increase soil water retention, evapotranspiration and total dry matter yield in drought conditions, but that this may not correspond to an increase in grain yield.  相似文献   

Do different agronomic soil tests identify similar nutrient deficiencies?     

Tuomas J. Mattila  Jukka Rajala 《Soil Use and Management》2022,38(1):635-648

Traditionally, locally calibrated soil tests were used for fertilizer and lime recommendations. Farmers and advisors are increasingly using new ‘universal’ soil tests without local calibration. The objective of this study was to compare five commercially available soil tests and to determine whether they would provide similar recommendations. In total, 24 fields in Western Finland were sampled for 4 years while being treated with fertilizers, lime and manure. The soil samples were analysed with Mehlich-3, ammonium acetate, H3A, hydrochloric acid and mild acetic acid (Spurway) extractants. In addition, Soil Health Tool (CO₂ burst, water-soluble C and N) and tissue testing were conducted. The different tests extracted different orders of magnitude of nutrients (especially P and Mg), but the results from the different extractions were correlated. Mehlich-3 degree of phosphorus saturation (DPS) presented a threshold, below which soluble phosphorus was not detected. Similar thresholds were found for P, S and Mg. Mehlich-3 and ammonium acetate provided similar results for Ca, Mg and K and can be used interchangeably for liming recommendations. Mehlich-3 identified more fields with Zn, Cu, B and S deficiencies and less fields with Mn deficiencies compared with ammonium acetate + EDTA and tissue testing. The tests had strong correlation, but the determination of nutrient deficiencies needs local calibration of deficiency limits.  相似文献   

Biochar composites: Emerging trends,field successes and sustainability implications     

Liuwei Wang  Yong Sik Ok  Daniel C. W. Tsang  Daniel S. Alessi  Jörg Rinklebe  Ondřej Mašek  Nanthi S. Bolan  Deyi Hou 《Soil Use and Management》2022,38(1):14-38

Engineered biochars are promising candidates in a wide range of environmental applications, including soil fertility improvement, contaminant immobilization, wastewater treatment and in situ carbon sequestration. This review provides a systematic classification of these novel biochar composites and identifies the promising future trends in composite research and application. It is proposed that metals, minerals, layered double hydroxides, carbonaceous nanomaterials and microorganisms enhance the performances of biochars via distinct mechanisms. In this review, four novel trends are identified and assessed critically. Firstly, facile synthesis methods, in particular ball milling and co-pyrolysis, have emerged as popular composite fabrication strategies that are suitable for large-scale applications. Secondly, biochar modification with green materials, such as natural clay minerals and microorganisms, align well with the on-going green and sustainable remediation (GSR) movement. Furthermore, new applications in soil health improvement and climate change mitigation support the realization of United Nation's Sustainable Development Goals (SDGs). Finally, the importance of field studies is getting more attention, since evidence of field success is critically needed before large-scale applications.  相似文献   

A model ensemble approach to determine the humus building efficiency of organic amendments in incubation experiments     

Anton A. Gasser  Julius Diel  Kerstin Nielsen  Paul Mewes  Christof Engels  Uwe Franko 《Soil Use and Management》2022,38(1):179-190

Organic amendments are important to sustain soil organic matter (SOM) and soil functions in agricultural soils. Information about the contribution of organic amendments to SOM can be derived from incubation experiments. In this study, data from 72 incubated organic amendments including plant residues, digestates and manure were analysed. The incubation data was compiled from three experimental setups with varying incubation times, soils and incubation temperatures, in which CO₂ release was measured continuously. The analysis of the incubation data was performed with an approach relying on conceptual parts of C-TOOL, CCB, Century, ICBM, RothC and Yasso which are all well-approved first-order carbon models that differ in structure and abstraction level. All models are an approximation of reality, whereby each model differs in understanding of the processes involved in soil carbon dynamics. To accumulate the advantages from each model a model ensemble was performed for each substrate. With the ability of each carbon model to compute the distribution of carbon into specific SOM pools a new approach for evaluating organic amendments in terms of humus building efficiency is presented that, depends on the weighted model fit of each ensemble member. Depending on the organic substrate added to the soil, the time course of CO₂ release in the incubation studies was predicted with different accuracy by the individual model concepts. Averaging the output of the individual models leads to more robust prediction of SOM dynamics. The E_HUM value is easy to interpret and the results are in accordance with the literature.  相似文献   

测量模拟土体zeta电位的简易流动电位测量装置及其使用方法     

李忠意  刘芳铭  吴金雯  徐仁扣  谢德体 《土壤学报》2022,59(3)

本文展示了一款可应用于土壤学领域研究的简易流动电位测量装置。为验证该装置的可行性,采用石英砂和包铁石英砂模拟土体所具有的多孔结构和表面电荷特征,基于流动电位法测量了石英砂在不同浓度（0.01、0.05、0.1、0.5、1.0、2.0和5.0 mmol?L-1）NaCl溶液中的zeta电位和石英砂与包铁石英砂在不同pH（4.4、5.2、6.1、6.6、6.9、7.7和8.0）电解质溶液中的zeta电位。同时采用电泳法测量了石英砂胶体在不同pH电解质溶液的zeta电位以作比较。结果表明：在考虑表面电导时,流动电位法测得石英砂在不同浓度NaCl溶液中的zeta电位随溶液浓度的升高逐渐往正值方向移动。这是由于随着离子强度增加,石英砂的双电层厚度受到压缩,zeta电位的绝对值逐渐降低;相同离子强度下,随溶液pH升高,石英砂和包铁石英砂表面官能团发生去质子化作用,流动电位法测得石英砂和包铁石英砂的zeta电位均随pH升高而逐渐降低;由于电荷屏蔽作用,在带负电荷的石英砂表面包被带正电荷的氢氧化铁后,流动电位法测得包铁石英砂的等电点pH（IEP）介于石英砂和氢氧化铁的IEP。此外,流动电位法测得的石英砂颗粒在不同pH电解质溶液中的zeta电位与电泳法测得的石英砂胶体在不同pH电解质溶液中的zeta电位具有较好的一致性。可见采用自制流动电位装置所获结果均与理论预测及常规电泳法测定结果相符,准确度较高。自制流动电位装置结构简单、操作方便、加工制造容易。该装置可被土壤学领域的研究者借鉴参考,以望为土壤电化学研究工作做出贡献。  相似文献   

不同改良措施对第四纪红壤酶活性的影响     

赵婧  王亚男  曾希柏  文炯  温云杰  吴翠霞  郑重 《土壤学报》2022,59(3)

红壤是我国重要的土壤类型之一,其耕地地力低下问题亟待解决。探究不同改良措施影响下红壤地力提升效果,对实现中低产田可持续利用具有重要意义。本研究以湖南第四纪红黏土发育的旱地红壤为研究对象,分析了休闲（F）、不施肥（CK）、单施无机肥（NPK）、无机肥配秸秆还田（NPKS）、无机肥配施生石灰（NPKL）、无机肥配施骨粉有机肥（NPKA）和无机肥配施生物有机肥（NPKC）等改良措施下不同土层和改良年限土壤中pH及养分含量的变化,并利用微孔板荧光法比较了土壤中碳氮磷循环相关酶活性的差异。结果表明,不同改良措施显著影响土壤养分及酶活性。与CK相比,2020年NPKC处理0～20 cm土层中有机质（SOM）、全氮（TN）、全磷（TP）和有效磷（AP）含量分别提高了73%、29%、61%和1 847%,同时该处理也显著增加了参与碳循环α-1,4-葡糖苷酶（αG）、β-1,4-葡糖苷酶（βG）、β-1,4-木糖苷酶（βX）、纤维二糖水解酶（CBH）和参与氮循环β-1,4-N-乙酰基氨基葡萄糖酐酶（NAG）活性。相关分析表明,SOM与αG、βG、βX、CBH和NAG酶活性呈显著正相关（P < 0.01）,pH与酸性磷酸酶（ACP）活性呈显著负相关（P < 0.01）。改良措施对0～20 cm土层酶活性的影响大于20～40 cm。2019年,NPKA处理0～20 cm土层中CBH酶活性较CK提高了352%,而在20～40 cm土层中CBH酶活性仅较CK提高了2%。此外,不同改良措施土壤中ACP酶活性也呈现出随改良年限增加而增加的趋势。综上可知,无机肥配施有机物料显著提升红壤养分状况,改善土壤酶活性,可作为贫瘠红壤地力提升的有效改良措施。  相似文献   

喀斯特生态系统土壤表面电化学特征及其影响因子     

赵楚  盛茂银  李雨萱  白义鑫  刘树西 《土壤学报》2022,59(3)

以西南喀斯特典型石漠化生态系统土壤为研究对象,采用空间替代时间的方法,研究石漠化演替过程中土壤表面电化学特征演变规律及其与土壤理化性质的相关性。采用物质表面联合分析法对不同石漠化等级土壤表面电化学属性及进行测定。结果表明,土壤表面电荷密度、表面电场强度、比表面、表面电荷数量随石漠化强度的增加而下降,其变化范围分别为0.34 C·m-2~0.42 C·m-2、4.85×108 V·m-1~5.86×108 V·m-1、47.11 m2·g-1~53.16 m2·g-1、16.86 cmol·kg-1~22.82 cmol·kg-1,土壤表面电位随石漠化强度的增加而上升,其变化范围为-113.74 mV~ -115.10 mV;研究区黏土矿物组成为伊利石、高岭石、绿泥石、伊蒙混层、绿蒙混层,且以绿蒙混层为主;土壤黏粒、砂粒、非晶质氧化铝、胡敏酸是影响喀斯特石漠化地区土壤表面电化学属性变化的主要因素,解释率分别为48.3%、38.1%、13.0%、12.0%;土壤粒径组成、有机质组分和金属氧化物对土壤表面电化学特征影响由强到弱依次分别为：土壤黏粒>砂粒>粉粒,胡敏酸>有机碳>富里酸,非晶质氧化铝>游离氧化铁>非晶质氧化铁。本研究对中国西南喀斯特石漠化土壤管理与调控、退化植被恢复重建具有重要意义。  相似文献   

基于贡献率模型的崩塌易发性评价——以广州市白云区为例     

邓日朗  陈凌伟  蔡俊坚  詹华炜  郑先昌 《水土保持通报》2022,42(4):218-226

[目的] 根据地质灾害野外普查空间数据库,分析花岗岩风化残积土发育地区崩塌形成机理和破坏模式,探究不同环境孕灾因子对崩塌发育的贡献率,评估崩塌灾害空间易发性与分布规律,为中国东南沿海地质灾害多发区的灾害防治工作提供科学支持。[方法] 在分析广州市白云区花岗岩风化残积土崩塌发育特征的基础上,选取高程、坡度、坡向、地形起伏度、距地表水体距离、降雨量、地层岩性、土地利用类型共8个与崩塌灾害发育密切关联的致灾因子构建崩塌灾害易发性评价指标体系,叠加研究区内404个历史崩塌数据,依据贡献率模型计算统计各指标因子崩塌灾害敏感性和空间分布特征。采用各二级指标因子贡献率的修正样本差确定因子权重。[结果] ①研究区内坡度、高程和地形起伏度对崩塌易发性贡献程度较高,坡向、地层岩性、降雨量在崩塌灾害易发性评价中贡献程度较低。②极高易发区主要集中在丘陵西麓,崩塌易发性由山地线范围外层边缘向中心逐级降低。③崩塌极高易发区和高易发区崩塌比率占总崩塌比率超过85%,模型易发性评价成功率和预测率分别达到91.3%和92.6%。[结论] 斜坡地形地貌因子对崩塌发育影响较显著,基于贡献率的崩塌灾害易发性评价模型能够客观量化指标因子权重,模型预测评价结果精度较高,易发性区划符合实际崩塌发育空间分布特征。  相似文献   

不同水分条件下保水剂对黄瓜根系和叶片生理特征的影响     

纪冰祎  赵驰鹏  吴玥  宋吉青  白文波 《水土保持通报》2022,42(2):114-121

[目的]研究不同土壤干旱生境中保水剂对黄瓜根系和叶片生理特征的影响,探讨其生长效应与土壤水分的内在联系,为保水剂的合理施用和农田科学灌溉等提供一定的技术参考。[方法]利用盆栽模拟试验,通过定量灌水,系统研究在3种不同的土壤水分条件下,保水剂对黄瓜根际水分、根系形态特征、叶绿素荧光参数和叶片气孔性状等生理特性的影响。[结果](1)不同水分条件下,保水剂处理的黄瓜根系生长受到明显抑制。与对照相比,保水剂处理组在土壤含水量为田间持水量70%(FC₂)和55%(FC₃)时的总根长、平均根系直径、总根体积、根表面积和根干重均显著降低,分别降低了3.4%,24.2%,62.1%,41.0%和51.6%以上。(2)随着干旱胁迫的加剧,保水剂处理叶片的有效光合效率(F_v′/F_m′)和实际量子产量[Y(Ⅱ)]较对照出现先升后降的变化趋势,非光化学淬灭(NPQ)则呈相反的变化;尤其在FC₂和FC₃处理时,保水剂处理促使黄瓜叶片的光化学淬灭(q_P)较对照分...  相似文献