Substrate effects on vegetative and reproductive growth of Ornithogalum thyrsoides “Royal Beauty”

The effect of soil amendment with degraded granite or perlite on plant growth of Ornithogalum thyrsoides was investigated in Central Chile. Bulbs were planted in April in raised soil beds under greenhouse. Three different substrates were compared: control (unamended soil), decomposed granite soil (DG) and soil in proportion 1:2, and perlite and soil in proportion 1:2. Soil nutrient availability in all treatments was considered higher than the plant requirements. The plants in the unamended soil had the greatest flower stem diameter, total fresh weight, and aboveground fresh weight. In terms of stem length, inflorescence length, belowground structures fresh weight, and inflorescence fresh weight, perlite with soil had similar results as unamended soil, but never better. Our results indicate that, under the conditions of this experiment, DG or perlite is not recommended for growing O. thyrsoides, since they did not improve either vegetative or reproductive growth.     

提高岩溶地区石灰土生产力试验研究

连续2年在石灰土上进行提高土地生产力的相关试验,结果表明:与传统栽培(CK)相比,平衡施肥(处理1)、施用土壤改良保水剂(处理2)、少耕覆盖死覆盖(处理3)、少耕覆盖活覆盖(处理4)、育苗移栽、合理密植措施均能有效的提高土地生产力。表现为能有效提高土壤含水量、改善土壤理化性状、增加产量产值。2年平均:处理2~4全生育期土壤水分含量比传统栽培提高6.7%、16.6%、10.1%,雨水透地前提高7.7%、17.4%、8.1%;处理3对土壤理化性状的改善作用最明显,有机质、全氮含量比试验前分别提高9.9%、6.4%,土壤容重降低0.22 g/cm3、土壤孔隙度提高4.1个百分点,其余处理稍次之;处理1~4产量比CK平均增加13.4%、36.3%、28.5%、27.8%,纯收入平均增加20.9%、38.7%、22.7%、37.9%。     

淮北沿海中低产地区农业增产增效配套技术开发及应用

针对江苏省淮北沿海中低产地区盐碱土特点，以响水县老舍实验区为中心，通过水利建设与农艺措施相结合，递进改良盐碱土，综合运用种养业先进适用技术，优化农业内部结构，实现了该地区农业增产增效。     

我国南方红壤酸化问题及改良修复技术研究进展

近年来我国南方红壤酸化问题日益突出,严重制约了该区域的粮食安全和农业可持续发展。主要介绍了南方红壤酸化的现状和危害,总结了近年来红壤酸化加速的主要成因,从无机改良、有机改良、生物修复和生物质炭改良修复酸化土壤等4个方面分析了红壤酸化改良修复技术及基本原理,以期为红壤酸化改良修复工作提供参考。     

清末民国时期安徽的农业改良

清末民初，安徽农业改良机构渐次成立，形成了包括农政机关、农会、农业推广机构、农业研究机构和农业教育机构的农业改良机构体系。其改良的举措，主要有举办农事调查、宣传农业科技知识、研究和推广优良品种、引进新农具和化肥、防治病虫害等。尽管改良取得了一定成效，但没有改变近代安徽农业的落后局面。     

Driving forces for sodium removal during phytoremediation of calcareous sodic and saline–sodic soils: a review

Abstract. Sodic and saline–sodic soils are characterized by the occurrence of sodium (Na⁺) at levels that result in poor physical properties and fertility problems, adversely affecting the growth and yield of most crops. These soils can be brought back to a highly productive state by providing a soluble source of calcium (Ca²⁺) to replace excess Na⁺ on the cation exchange complex. Many sodic and saline–sodic soils contain inherent or precipitated sources of Ca²⁺, typically calcite (CaCO₃), at varying depths within the profile. Unlike other Ca²⁺ sources used in the amelioration of sodic and saline‐sodic soils, calcite is not sufficiently soluble to effect the displacement of Na⁺ from the cation exchange complex. In recent years, phytoremediation has shown promise for the amelioration of calcareous sodic and saline–sodic soils. It also provides financial or other benefits to the farmer from the crops grown during the amelioration process. In contrast to phytoremediation of soils contaminated by heavy metals, phytoremediation of sodic and saline–sodic soils is achieved by the ability of plant roots to increase the dissolution rate of calcite, resulting in enhanced levels of Ca²⁺ in soil solution to replace Na⁺ from the cation exchange complex. Research has shown that this process is driven by the partial pressure of CO₂ (P_CO2) within the root zone, the generation of protons (H⁺) released by roots of certain plant species, and to a much smaller extent the enhanced Na⁺ uptake by plants and its subsequent removal from the field at harvest. Enhanced levels of P_CO2 and H⁺ assist in increasing the dissolution rate of calcite. This results in the added benefit of improved physical properties within the root zone, enhancing the hydraulic conductivity and allowing the leaching of Na⁺ below the effective rooting depth. This review explores these driving forces and evaluates their relative contribution to the phytoremediation process. This will assist researchers and farm advisors in choosing appropriate crops and management practices to achieve maximum benefit during the amelioration process.     

四湖地区涝渍地综合改良对稻田节肢动物群落的态效应

研究了涝渍地综合改良对稻田节肢动物群落的结构和季节动态及多样性局的影响。发现改良后的稻田节肢动物群落结构更加复杂，多样性增加，时间稳定性亦增强。     

野葛及百喜草对红壤坡地水土保持及土壤改良的效应

试验研究红壤坡地野葛水土保持和土壤改良效应结果表明,横峰野葛和百喜草可有效增大土壤持水量、土壤孔隙度和降低土壤容重,提高土壤pH值、有机质和N、P、K含量,减少土壤侵蚀量和径流量,水土保持和改良土壤效果明显,且野葛综合效果优于百喜草。     

Alleviation of Soil Aluminum Phytotoxicity in a Typical Paddy Soil in Southern China by Using Weak Organic Acids

Weak organic acids including tartaric and citric acids were applied to a typical paddy soil in southern China to test their effects on rice in the field for three years. Their effects were also compared with top dressings of the two acids, basal application of diammonium acid phosphate, calcium carbonate, and the control. The results showed that rice grain yield of the citric acid treatment was significantly higher than that of the control and the same difference was also observed for the filled spikelets per panicle. There were no significant difference among all the treatments and the control on the accumulation of above ground dry matter. However the root dry matter, length, peroxidase activity, and white root number of citric acid treatment were significantly higher than that of the control, while no significant differences among other treatments were observed. Basal application of citric acid played a positive role on this soil.     

不同改良物质对苏打碱土盐碱度及水稻生长的影响

针对吉林省西部新垦水田地盐碱化严重等问题,研究了脱硫石膏(GR)、沙土(SS)、农家肥(FM)、混合(M)4种处理对苏打碱土新垦水田的改良作用.结果表明：M处理的水稻株高与SS、FM、对照(CK)间存在极显著差异(P<0.01);GR处理的水稻根长、叶面积指数与CK、FM存在极显著差异(P<0.01);M和GR处理水稻株高、根长和叶面积指数差异不显著,表明M处理中的脱硫石膏成分对土壤改良的贡献率最大,进而影响水稻的形态特征.M处理的水稻根生物量最高,GR处理的水稻茎、叶、穗生物量和总生物量最高,并且与CK间存在极显著差异(P<0.01).在改良12个月后,0~20 cm土层土壤的pH在M与CK间存在显著差异 (P<0.05);CK、SS与GR处理间EC值差异极显著(P<0.01).在改良17个月后,M与CK间土壤pH存在极显著差异(P<0.01);CK、FM和SS处理与GR、M处理间EC、ESP值存在极显著差异(P<0.01),M处理的EC值最高、ESP最低.GR处理水稻产量达到 6 071 kg/hm².