Effects Of Lime Application Research Articles

Effect of lime application on phosphorus adsorption and desorption in post-active acid sulfate soil, Thailand

The application of lime is the general method of improving acid sulfate soils. However, if a lot of lime is applied, it can reduce the bioavailability of nutrients in the soil, especially phosphorus. The objective of this study was to investigate the effects of liming at different rates on the availability, adsorption, and desorption of phosphorus in two post-active acid sulfate soils (Ay and Se). The experiment was performed in the laboratory. The experiment was laid out in a completely randomized design (CRD) with four treatments and three replicates, i.e., the application of lime at a rate of 0 (control), 0.5, 1.0, and 2.0 times the lime requirement (LR). The lime requirements of the soils in the Ay and Se were 5,690 and 12,250 kg CaCO3/ha, respectively. The finding revealed that increasing the amount of lime could increase soil pH, available phosphorus, and the phosphorus activation coefficient. Application of lime at a dosage of 1.0-2.0 LR resulted in the highest phosphorus adsorption maximum (Qm) (380 mg/kg), while 0.5 LR resulted in the lowest Qm (353 mg/kg) in Se soil only. As lime dosage increased, phosphorus desorption maximum (Dm) and phosphorus desorption ratio (Dr) increased, with 2.0 LR yielding the highest values (124 mg/kg and 23.6 percent for Ay soil, and 77.3 mg/kg and 20.3 percent for Se soil, respectively). The results suggested that applying lime according to the lime requirement test, especially 2.0 LR, is the best option to promote the release of phosphorus in post-active acid sulfate soils.

Liming reduces nitrogen uptake from chemical fertilizer but increases that from straw in a double rice cropping system

Liming materials are widely applied to alleviate soil acidification and increase rice yield in acidic soils, but their effects on nitrogen (N) use efficiency are still unclear. Here, we conducted a field-, pot-, and micro-plot experiment to investigate how the application of slaked lime (i.e., Ca(OH)2) affects the fate of chemical fertilizer-N and straw-N in a double rice cropping system. In the field experiment, liming increased grain yield and N uptake by an average of 9.0% and 10.6%, respectively. In contrast, CaCl2 application did not affect rice yield and N uptake, suggesting that the effects of lime application were not related to the addition of Ca2+. Results from a 15N tracer experiment (i.e., 15N-labeled urea and straw) indicated that liming reduced N uptake from fertilizer (−5.7%), but increased N uptake from straw (+31.3%). Liming also reduced soil retention of both urea- and straw-N and increased their loss rates. Taken together, our results indicate that although liming increases rice yield and N uptake, it lowers the use efficiency of fertilizer N and facilitates N losses. In addition, our results emphasize the need for long-term studies on the impact of liming on soil N dynamics in paddy soils.

Soil enzymatic activity under coffee cultivation with different water regimes associated to liming and intercropped brachiaria

ABSTRACT: This research evaluated the effects of coffee cultivation with two different water regimes associated or not with liming and the presence/absence of brachiaria as intercrop on the activities of the soil enzymes β-glucosidase, arylsulfatase and acid phosphatase. The study was carried out at the experimental farm of Embrapa Cerrados, using the cultivar IAC 144 (Coffea arabica L.), under a clayey dystrophic Cerrado Oxisol. Two water regimes (WR) were considered, WR1 with irrigation shifts throughout the year and WR3 with controlled water stress, for about 70 days, in the dry season. In each water regime, effects of lime application (with/without) and the presence/absence of brachiaria cultivated between the lines of coffee plants were evaluated. The activities of the enzymes β-glucosidase, arylsulfatase and acid phosphatase were evaluated during the rainy and dry seasons. Liming and intercropped brachiaria positively affected the activities of the three enzymes assessed in this study at varying degrees, depending on season and/or the WR. Our findings evidenced that intercropped brachiaria in coffee rows was the factor that most positively impacted soil enzymes activities.

Changes in pore networks and readily dispersible soil following structure liming of clay soils

Structure liming aims to improve soil structure (i.e., the spatial arrangement of particles and pores) and its stability against external and internal forces. Effects of lime application on soil structure have received considerable interest, but only a few studies have investigated effects on macro- and mesopore networks. We used X-ray computed tomography to image macropore networks (ø ≥ 0.3 mm) in soil columns and mesopores (ø ≥ 0.01 mm) in soil aggregates from three field sites with (silty) clay soils after the application of structure lime (3.1 t ha−1 or 5 t ha−1 of CaO equivalent). Segmented X-ray images were used to quantify soil porosity and pore size distributions as well as to analyse pore architecture and connectivity metrics. In addition, we investigated the amount of readily dispersible soil particles. Our results demonstrate that structure liming affected both, macropore networks and amounts of readily dispersible soil to different degrees, depending on the field site. Significant changes in macropore networks and amounts of readily dispersible soil after lime application were found for one of the three field sites, while only some indications for similar changes were observed at the other two sites. Overall, structure liming tended to decrease soil macroporosity and shift pore size distribution from larger (ε>1.0 mm) and medium sized macropores (ε0.3–1.0 mm) towards smaller macropores (ε0.1–0.3 mm). Furthermore, liming tended to decrease the critical and average pore diameters, while increasing the surface fractal dimension and specific surface area of macropore network. Structure liming also reduced the amounts of readily dispersible soil particles. We did not find any changes in mesopore network properties within soil aggregates or biopore networks in columns and aggregates. The effects of lime on macropore networks remain elusive, but may be caused by the formation of hydrate phases and carbonates which occupy pore space.

Effects of Lime Application on Activities of Related Enzymes and Protein Expression of Saponin Metabolism of <i>Panax notoginseng</i> under Cadmium Stress

Effects of Lime Application on Activities of Related Enzymes and Protein Expression of Saponin Metabolism of <i>Panax notoginseng</i> under Cadmium Stress

Effects of lime application on nitrogen and phosphorus availability in humic soils

There is a paucity of information on nitrogen (N) and phosphorus (P) mineralization in humic soils, which are highly weathered and have high carbon (C) (>1.8%). This study was to determine effects of liming on N and P mineralization in humic soils. Lime was applied to reduce acid saturation to 20% of the 0–10 and 10–20 cm depths of soils from Eston and Eshowe. Soils were incubated at field capacity moisture and 25 °C temperature, with destructive sampling after 0, 7, 14, 21, 28, 56, 84 and 112 days. Samples were analysed for pH, ammonium- and nitrate-N and extractable P. Phosphorus pools and soil microbial biomass C and N (SMBC and N) were analysed after 112 days only. Soil pH increased up to day 7 and decreased thereafter in Eston soil but decreased throughout the incubation in Eshowe soil. Ammonium- and nitrate-N increased with lime rate, with ammonium-N peaking after 7 and 14 days for Eston and Eshowe soils, respectively. The 0–10 cm depth had higher ammonium-N than 10–20 cm for both soils. Nitrate-N increased with corresponding decrease in ammonium-N. Extractable P decreased till day 21 and increased thereafter in Eston soil, with slight changes in Eshowe. Higher lime rate decreased Al-P, Fe-P and CBD-P and increased soluble-P, Ca-P, and SMB-C and N for both soils. The findings imply that liming humic soils increase nitrate-N and, to a lesser extent, extractable P, possibly improving productivity and exposing N to leaching.

Effects of lime, phosphorus and stocking rate on an extensively managed permanent pasture: botanical composition and groundcover

Low phosphorus (P) constrains productivity of many of the permanent pastures of south-eastern Australia where wool and meat production are important. Whereas the need for fertilisation with P is indisputable for many soils, the benefits of liming to ameliorate soil acidification are not always clear in terms of forage production or quality. This experiment, by measuring botanical composition and groundcover over 10 years, aimed to address the issue of forage composition and groundcover. Merino wethers were continuously grazed on a permanent pasture under two stocking rates (low and high) following treatments with three rates of surface-applied lime and two rates of P. The lime rates were: nil, and sufficient to raise the pHCaCl2 of the 0–10 cm soil layer to 5.0 and to 5.5. Phosphorus was added as two rates of single superphosphate: 125 kg ha–1 every 2–3 years, and 250 kg ha–1 every year. Two hypotheses were proposed: (i) as lime application rate increased, it would lead to the pasture swards having a higher percentage of species favourable for grazing animal production, and a higher level of sward groundcover would be maintained; and (ii) legume presence would be favoured by a higher level of applied P over the long term. The Millennium Drought (1997–2008), which coincided with this experiment (1998–2008), tended to mask or reduce lime effects; nevertheless, the higher legume content in the sward, as well as the superior groundcover found in the high lime–high P treatments at various times throughout the experiment and at its completion compared with the nil-lime control, indicated positive forage effects of lime application. Moreover, by the termination of the experiment in 2008, groundcover generally tended to be lower under nil lime than in treatments that had received lime. The higher proportion of legume in the sward was closely linked to greater applied P, although this did not occur at the low stocking rate in the absence of lime. By contrast, similar high P–low stocking rate treatments but with applied lime had the highest clover contents. It is proposed that the poor persistence of the treatment without lime may be due to a combination of poor legume seedset, because of excessive competition from accompanying grasses, and aluminium toxicity adversely affecting legume growth.

Effects of Lime Application and Understory Removal on Soil Microbial Communities in Subtropical Eucalyptus L’Hér. Plantations

Soil microorganisms play key roles in ecosystems and respond quickly to environmental changes. Liming and/or understory removal are important forest management practices and have been widely applied to planted forests in humid subtropical and tropical regions of the world. However, few studies have explored the impacts of lime application, understory removal, and their interactive effects on soil microbial communities. We conducted a lime application experiment combined with understory removal in a subtropical Eucalyptus L’Hér. plantation. Responses of soil microbial communities (indicated by phospholipid fatty acids, PLFAs), soil physico-chemical properties, and litter decomposition rate to lime and/or understory removal were measured. Lime application significantly decreased both fungal and bacterial PLFAs, causing declines in total PLFAs. Understory removal reduced the fungal PLFAs but had no effect on the bacterial PLFAs, leading to decreases in the total PLFAs and in the ratio of fungal to bacterial PLFAs. No interaction between lime application and understory removal on soil microbial community compositions was observed. Changes in soil microbial communities caused by lime application were mainly attributed to increases in soil pH and NO3–-N contents, while changes caused by understory removal were mainly due to the indirect effects on soil microclimate and the decreased soil dissolved carbon contents. Furthermore, both lime application and understory removal significantly reduced the litter decomposition rates, which indicates the lime application and understory removal may impact the microbe-mediated soil ecological process. Our results suggest that lime application may not be suitable for the management of subtropical Eucalyptus plantations. Likewise, understory vegetation helps to maintain soil microbial communities and litter decomposition rate; it should not be removed from Eucalyptus plantations.

Nutritional Behavior of Heliconia Grown Under Different Levels of Lime

Production and commercialization of tropical flowers and plants has grown in recent years, mainly due to the increasing value of these products in temperate climate countries, such as heliconia, one of the most cultivated tropical ornamental plants in Brazil. This study was developed to determine the effect of lime applications on the nutrients in heliconia plants (Heliconia psittacorum L. × Heliconia sparthocircinata Arist. [cv. Golden Torch]) cultivated in yellow latosol in a greenhouse. The macronutrient levels in the leaves, pseudostem and roots of the heliconia plants were determined after cultivating the plants in containers with a medium texture, yellow latosol, collected from the 0 to 20 cm layer and submitted to doses of 0, 0.9, 2.6, 4.2 and 5.9 t of lime ha-1. Nitrogen and phosphorous performed better in the absence of the correction and in the 0.9 t ha-1 dose for the vegetative parts of the heliconia plants. The application of dolomitic lime promoted greater absorption of potassium, calcium and magnesium, and sulfur performed better for the doses 2.6 and 5.9 t of lime ha-1, for the pseudostem and roots, respectively.

Silage maize quality in different uses of Italian ryegrass and soil management methods after liming

ABSTRACTThe effects of lime application with multiple soil management methods and uses on dry matter (DM) yield and crude protein (CP) content of Silage maize cropping in succession with Italian ryegrass (ryegrass) from 2009 to 2014 in a southern Brazilian Oxisol were studied. The experimental design was completely randomized block in split-plot with four replications. The main plot treatments were the four soil management methods: conventional tillage (CT), minimum tillage (MT), no-tillage (NT) and chiseled no-tillage (CNT). The sub-plots treatments were the three uses of Italian ryegrass (ryegrass): cover crop (CC), silage (S), and grazing dairy heifers as part of integrated crop-livestock system (ICL). In all the years, the maize was sown approximately 30 days after the ryegrass desiccation with herbicide. In the medium-term (5 yrs.) after liming, soil management methods did not change DM yield and CP content in silage maize. The use of ryegrass for S and ICL did not change DM yield, but notably maintained or increased CP content in silage maize after liming. The use of ryegrass only as CC provided less measurable benefits than the combined production system of silage maize with ryegrass.

Effects of Lime Applications on Chemical Properties of Soil and Rice Yields in Long-term Fertilization Experiment

Monitoring of soil fertility and crop productivity in long-term application of fertilizers is necessary to use fertilizers efficiently. This study was conducted to investigate effects of continuous application of lime for rice cultivation from 1969 to 2014. The treatments were no lime treatments (N, NPK, NPKC, and NPKS) and lime treatments (N+L, NPK+L, NPKC+L, and NPKS+L). The application of lime in addition to N, NPK, and NPKC tended to increase pH, exchangeable Ca, and available SiO2. The input of mean annual 1,170 Mg ha -1 yr -1 of lime increased pH 0.0042 yr -1 , 0.0062 yr -1 , 0.0127 yr -1 , and 0.0041 yr -1 in lime treatments (N+L, NPK+L, NPKS+L, and NPKC+L) compared with no treatments (N, NPK, NPKS, and NPKC), respectively. The mean annual Ca field balance varied from 169 to 561 kg ha -1 yr -1 in no treatments, from 871 to 1,263 kg ha -1 yr -1 in lime treatments, indicating that Ca was accumulated in the soils. The mean annual Ca field balance in silicate fertilizer treatments (NPKS, NPKS+L) were higher than that of other treatments because silicate fertilizer included Ca component. Grain yield of rice had no significant differences between no lime treatments and lime treatments. Thus the application of lime led to changes in soil chemical properties but had no impact on the production of rice.

Effects of Adding Lime to Improve Levee Soil Layer Using Numerical Method (Case Study: Part VI of Bijar – Zanjan Four-Lane)

Abstract. Soil stabilization is defined as improvement of its physical and engineering properties to provide a series of pre-determined objectives. Some soil are poor due to unfavorable technical specifications or consisting clay or silt to work in road construction. In this study, the effects of lime application in soil stabilization have been investigated in levee soil layers of part 6 of Bijar – Zanjan four-lane in Kordestan province. In the next stage, remodeling of this issue in the implementation of reinforcing layers and the results of two of these cases were compared. Finite difference FLAC.2D software was used to model soil profiles. Comprehensive results were obtained examining the role of factors such as soil type, the percentage of lime, water content, particle of reinforcing layers, energy caused by density etc.

Long-term effects of gap creation and lime application on element input and output in a European beech (Fagus sylvatica L.) forest

Four gaps of 30 m diameter were cut in a mature European beech (Fagus sylvatica L.) forest in 1989. In two of the gaps and their surrounding areas, dolomite lime (3 t ha−1) was applied. The study was designed to examine the long-term effects of lime application and canopy removal on element input via throughfall and output in seepage water at 80 cm depth in this European beech forest. Throughfall and seepage water were collected in the unlimed gap center, the limed gap center and the undisturbed beech stand in 1991, 1992, 1993, 1996 and 2012. The canopy opening increased the seepage water acidity from 1991 to 1996. The pH values of the seepage water were higher in the limed gaps than in the unlimed gaps during the five study periods. The amount of annual throughfall and of seepage water were higher in the gaps during the study period; in 2012, the annual amounts of seepage water were significantly higher in the gaps than in the closed stand, whereas the input of most elements decreased from 1991 to 2012. The seepage water in the unlimed gaps had higher nitrate nitrogen (NO3-N) concentrations, but lower sulfate sulfur (SO4-S) concentrations than in the limed gaps in 1991, 1992, 1993 and 1996. The amount of leaching NO3-N and SO4-S in 2012 was, however, significantly higher in the limed gaps than in the unlimed gaps, while the input of nitrogen (N) and SO4-S was significantly lower in the limed gaps than in the closed stand. In general, the annual amounts of element input via throughfall were higher in the closed stand than in the gaps. However, the element output through leaching was much higher in the gap centers than in the closed stand. The net losses of aluminum (Al), calcium (Ca), magnesium (Mg) and manganese (Mn) were higher in the unlimed gaps than in the limed gaps and the closed stand in 1991. In 2012, 23 years after liming and canopy opening, the effects of gaps and liming, and the interaction of gap and liming on element leaching, were still significant compared to the untreated stand. Overall, canopy opening reduced N, sulfate, Al, and base cation deposition in the long run. Canopy opening in combination with liming affected the seepage water acidity and the leaching losses of base cations up to 23 years after canopy removal and liming in this European beech forest.

Effect of Lime Application to Acidic Soils on Oleoresin Yield Tapped from Pine Plantations in South China

Oleoresin is a major non-forest product collected from commercially mature or near mature pine trees. Efforts have been made to increase oleoresin yield, but basically limited to the genetic improvement of planting materials and the application of chemical stimulants to tapping surface of trees. Nutrition management may play a role, particularly for pine stands suffering from soil acidification and degradation. We set up a field experiment including application of water retainer, NPK complex fertilizer, lime and borax in different combinations to pine stands for oleoresin tapping with extremely low soil pH value and nutrition. Lime significantly affected the annual yield of oleoresin tapped from two pine species studied (P P > 0.10). In addition, all of the four matters applied did not influence the growth of both pine species. We concluded that proper use of lime alone may generate 15% to 35% of gain in oleoresin production for pine plantations with similar soil conditions in the region. We also discussed the potential of comprehensive soil or site management, and proposed further research for improvement of pine oleoresin production.

Calagem na nutrição de cálcio e no desenvolvimento do sistema radicular da goiabeira

A aplicação de calcário em solos ácidos promove maior desenvolvimento do sistema radicular das plantas e consequentemente, melhora a absorção de água e nutrientes. O objetivo deste trabalho foi avaliar os efeitos da aplicação de calcário no solo, no desenvolvimento do sistema radicular e na nutrição de cálcio de goiabeiras cultivadas em um Latossolo Vermelho distrófico ácido. Analisaram-se amostras de solo coletadas em quatro pontos eqüidistantes, a 75 cm do tronco, nas camadas de 0-20 e 20-40 cm de profundidade, de parcelas que receberam 0, 3,7 e 7,4 t ha-1 de calcário. O calcário foi aplicado em pré-plantio, incorporado com arado de aivecas e grade aradora, na camada de 0-30 cm de profundidade. Durante o segundo e o terceiro ano de cultivo da goiabeira, avaliaram-se os efeitos da calagem nas propriedades químicas do solo. Aos 42 meses após a incorporação do calcário (terceiro ano de cultivo da goiabeira), realizou-se a amostragem das raízes com trado cilíndrico serrilhado para a avaliação da matéria seca e do teor de cálcio radicular e e também realizou-se a amostragem de folhas. A calagem promoveu a correção da acidez do solo, aumentando a saturação por bases, com conseqüente incremento da disponibilidade e absorção de cálcio pela planta, proporcionando maior desenvolvimento do sistema radicular da goiabeira. Concentrações de cálcio próximas de 30 mmol c dm-3 no solo e teor desse nutriente de 7,5 g kg-1 nas raízes, estiveram associados ao maior crescimento radicular da goiabeira.

신개간 및 기경작 초지토양간 목초의 생산성과 무기양분 함량 비교 II. 석회 시용에 따른 토양특성, 목초의 초기생육, 수량 및 무기양분 함량 변화

동일한 토양종류(토양명: 송정통)인 인접한 토양에서 신개간지와 다소 숙전화 된 기경작 초지토양 간의 비옥도 특성과 시비처리별 목초 생산성과 무기양분 함량차이를 비교.검토하고 자 기초시험으로 pot 시험을 수행하였다. 초지 토양의 비옥도 개량에 연관된 퇴비(I보), 석회 (II보) 및 인산(III보)의 시용효과를 단계별로 검토하였다. 본보(II)에서는 3요소 및 고토를 동일하게 기본시비를 한 조건에서 1) 무석회구, 2) 석회 보비구(27g), 3) 석회 다비구(54g, CaCO<TEX>$_3$</TEX>/pot)를 처리내용으로 한 두 토양간 석회의 비효를 비교.검토하였다. 1. 시험전 신개간지와 기존초지간 토양의 화학성(비옥도)에 큰 차이를 보였다. 초지토양 비옥도 등급기준(불량-보통-양호)에 기준 한 각 화학성을 신개간지 토양 ↔ 기경작 초지토양간의 차이를 일반적으로 비교하면 불량/보통 ↔ 보통/양호수준을 보였다. 2. 시험 후 토양특성의 변화를 보면 석회시 비로 두 토양 공히, 유효인산 함량은 약간 감소되었고, 유기물 함량은 변화를 보이지 안 했으며 치환성 Ca과 mg 함량이 높아졌다. 인산 흡수계수는 신개간 토양에서 크게 높아졌으나 기경작 초지토양에서는 석회 다비구에서 만 크게 높아졌다. 석회시비에 따른 유효인산 함량 의 저하와 인산흡수계수 상승의 부정적 영향을 퇴비와 병행시비의 경우 개선되었다. 3. 목초의 초기 생육상은 신개간지보다 기경작 초지토양에서 매우 양호하였고, 각 토양 공히 석회 다비구에서 불량해 진 경향을 보였다. 그러나 퇴비와 병행된 석회시비는 석회 단독 시비조건보다 크게 초기생육상이 양호해 졌다. 4. 목초의 수량은 대조구에서 신개간지에 비해 기경작 초지토양에서 50.9%의 더 높은 생산성을 보였다. 석회 보비구에서 각 토양 공히 대조구보다 15-18% 정도 증수하였고 반면에 석회 다비구는 보비구와 비슷하거나 다소 낮야지는 경향을 보였다. 5. 기경작 초지토양의 목초 중 Ca, mg 및 P 함량이 신 개간 토양의 목초 중 함량보다 다소 높았고 석회 보비구에서 Ca, mg 함량이 높아 졌으나 석회 보비구와 다비구간 차이는 경미하였다. This pot experiment was conducted to find out the forage productivity and contents of mineral nutrients in an orchardgrass sward affected by the compost lime, and phosphorus applications on the newly reclaimed and arable pasture soils. This 2nd part was concerned with the effect of lime application(L<TEX>$_{0}$</TEX>=control, L<TEX>$_1$</TEX>=279, L<TEX>$_2$</TEX>=54g CaCO<TEX>$_3$</TEX>/pot). The results obtained are summarized as follows: 1. There were considerable differences between the newly reclaimed and arable pasture soils in the soil chemical properties as follows in general; poor/common in the newly reclaimed soil longrightarrow and common/good in the arable pasture soil in terms of soil fertility standard. 2. It was recognized that the lime application was resulted in somewhat decrease of the concentrations of available P<TEX>$_2$</TEX>O<TEX>$_{5}$</TEX> and increase of P<TEX>$_2$</TEX>O<TEX>$_{5}$</TEX> absorbtion coefficient in the newly reclaimed soil, whereas these negative effects were positively enhanced by both lime and compost applications. The concentrations of exchangeable Ca and mg in both soils were increased by lime application. 3. The vigour at early growth stage of orchardgrass was better in the arable pasture soil than newly reclaimed soil. It was worsened by the heavy lime application(L<TEX>$_2$</TEX>), but this negative effect was positively enhanced by both lime and compost application. 4. Compared with the non-lime application, the forage yields of L<TEX>$_1$</TEX> treatment were increased in both soils by 15~18%. whereas it of L<TEX>$_2$</TEX> treatment was similar or lower than it of L<TEX>$_1$</TEX>. 5. The concentrations of Ca, mg, and P in orchardgrass were relatively higher in the arable pasture soil than the newly reclaimed soil, whereas there it was no difference in the K concentration. It was recognized that the concentrations of mg and Ca in orchardgrass were higher in the L<TEX>$_1$</TEX> treatment than the Lo treatment in both soils, whereas there were no difference in it between L<TEX>$_1$</TEX> and L<TEX>$_2$</TEX> treatments.ments.

Short-term effects of lime application on soil properties and fine-root characteristics for a 9-year-old Sitka spruce plantation growing on a deep peat soil

Summary Short-term effects of lime application on a 9-year-old Sitka spruce (Picea sitchensis (Bong.) Carr.)) stand planted on a deep blanket peat soil were investigated. Ground limestone was applied at three rates: 7.5 (L1), 15.0 (L2) and 22.5 t ha ‐1 (L3) plus a control (L0). The peat was sampled on the first and second growing seasons after lime application. Soil properties were examined for the litter layer and three depths of the peat profile at 5 cm intervals, while fine root ( 1 cm in length) in the litter layer compared with the L0 plots at the first growing season, while

Effects of lime application and test branch position on 14C-photosynthate partitioning in 3-year-old Sitka spruce (Picea sitchensis plants growing in pots containing peat soils

Experiments were carried out to determine the effects of lime and test branch position on percentage 14C-distribution within the plant, sink activities of plant fractions and total 14Crecovered in plants. The investigation was conducted with 3-year-old Sitka spruce [Picea sitchensis (Bong.) Carr.] seedlings planted in pots containing either limed or unlimed peat soils. To determine effects of test branch position on the above processes, upper test branches (UTB) and lower test branches (LTB) of plants were exposed to CO2 in October 1993, April 1994 and July 1994. These dates represented 100, 160 and 263 days after plants had been established under limed and unlimed conditions. Percentage 14C-distribution to the leader fraction decreased in October and increased in both April and July as a result of liming. In October, percentage 14C-distribution to the coarse-root fraction and sink activity of this fraction were increased by lime application. In July, the LTB and UTB of the limed plants retained 49 per cent and 51 per cent respectively higher concentrations of 14C as disintegrations per minute per gram dry weight compared with those of the unlimed plants. On all sampling occasions, sink activities of below-ground parts of the plant receiving 14C from the LTB were higher than when 14C was received from the UTB; such increases ranged from 55 per cent to over 300 per cent and were seemingly unrelated to liming treatment. In July, sink activity of above-ground parts of the limed plants importing 14C from the UTB was 100 per cent higher than when 14C was imported from the LTB. During the period of shoot elongation in April, both the UTB and LTB exported high percentages of their current photosynthate to the above-ground parts of the plant. When shoot elongation slowed down in July, the UTB and LTB exported high current photosynthate more equally to the above and below-ground parts of the plants. Concentrations of

Effect of Lime Application on the Movement of Atrazine and Nitrate-Nitrogen Through Undisturbed-Saturated Soil Columns

A study was conducted to determine the effects of three application rates of agricultural lime (0, 5, and 10 Mg ha−1) on atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5 triazine) and nitrate-nitrogen (NO3-N) transport through undisturbed-saturated soil columns. The soil columns were saturated with CaSO4 solution before leaching them with two pore volumes of a solution containing CaCl2 (0.005 M), atrazine (2000 μg a.i atrazine L−1), and KNO3 (200 mg-N L−1). Leachate samples were collected at the bottom of soil columns for the analysis of pH, NO3-N, and atrazine. The results of this study showed that with the increase in the lime application rates a significant increase and then a decrease in the leachate flow rate and volume was observed. The concentration of NO3-N in the leachate water increased with an increase in lime application rate. An increase in the application rate of lime had no significant effect on the pH values of the leachate. Also, an increase in the application rate of lime resulted in higher concentrations of atrazine in the leachate water.

Improvement of edaphic cyanobacterial population through liming in red and lateritic rice soils of West Bengal

In view of the predominance of acidic pH levels in lateritic soils and of the importance of this soil property on growth and distribution of blue-green algae or cyanobacteria (CB), the effect of lime application on the reduction of acidity and subsequently on growth and some related physiological properties of CB have been studied. Four soils with varying pH levels were used for this purpose and three lime treatments corresponding to 0,50 and 100% lime requirement were applied to each of them. The soils thus treated were incubated under submerged condition in an illuminated chamber for 6 weeks and were drawn at weekly intervals for studies of the number, fresh mass and chlorophyll content of the developed algal mass. Increase of the pH value of the soil through application of lime improved growth and relevant physiological properties of the CB.