Quality of Longitudinal Seed Distribution in Maize Cultivation in the Amazon Region

In Nebraska, early adopters of conservation tillage, especially those using no-till planting, had some concerns regarding planter performance, early season weed control, and possible yield reductions. Selected tillage and planting systems were used long term to evaluate effects on soybean [Glycine max (L.) Merr.] and grain sorghum [Sorghum bicolor (L.) Moench] yield, soil properties, and residue cover in a nonirrigated rotation. The six tillage and planting systems selected for evaluation were: no-tilI, no-till with row-crop cultivation, disk, double disk, chisel, and plow. In 1981, two sets of field plots were established near Lincoln, NE, on a Sharpsburg silty clay loam (fine, montmorillonitic, mesic Typic Argiudolls) so that both crops could be evaluated each year

Both alkalization and acidification of soil occurred when shoot and root materials from lupin and wheat were incubated in a red–brown earth soil, but with three different starting pH values, during a 70-day period. The response of soil pH change to the addition of organic matter depended on the type of plant materials and starting pH. The net effect of addition of lupin and wheat shoots to acid soils (pH<5) caused soil pH to increase, the addition of lupin roots to soils caused soil pH to decrease slightly, whilst with a higher pH soil (6.5) the wheat straw and lupin shoots raised pH and pH was unchanged for soil with addition of lupin roots. The ash alkalinity of plant materials and the mineralization of organic N are major reasons for the soil pH increase, and the nitrification of mineralized N results in soil pH to decrease. Whilst the data given here would suggest the likelihood of soil acidification occurring, particularly on poorly buffered soil given the inevitable influence of legume root materials, the overall directions of soil pH change in a cropping system that is legume-based will be very much influenced by the balance of many factors associated with the soil and plant system.

Urban roadside soils are important growth media for roadside trees. However, typical assessment variables are limited in describing the characteristics of roadside soils. We assessed the characteristics of roadside soils using the pre- and new suggested variables and recommended optimal soil variables that are representative of roadside tree health. Seventy-three roadside soils were collected for measurement, while six urban forest soils were prepared as a control. Samples were used to evaluate both pre-suggested and new variables. The former included bulk density, penetration resistance (PR), pH, organic matter (OM), fluorescein diacetate (FDA) activity, and respiration. To improve the pre-suggested variables, we modified the bulk density using PR and investigated the elemental ratios and stable isotopic signatures of particulate organic matter (POM). Two criteria were used to select the variables for urban roadside soils: (1) the variable should identify distinct characteristics of roadside and urban forest soils and (2) the variable should have a high correlation with urban tree health variables: leaf chlorophyll content and tree vigor. The bulk density measured using the conventional method underestimated soil compaction because obtaining intact cores was challenging. The modified bulk density (BDmodified) obtained from the soil PR is suggested to better represent soil compaction. The roadside soils were affected by de-icing materials, construction debris, and atmospheric alkali particles, which increased the soil pH. The unexpectedly higher OM contents in the roadside soils, where tree origins are limited, possibly due to soil OM sources such as vehicular emissions, animal excreta, and sewer flooding. These OM sources may alter the C/H ratio (POM-C/H) and the stable isotopic signature of POM, leading to OM quality changes. Soil respiration better reflected the changes in the microbial activity of the roadside soils, rather than FDA activity. The newly suggested soil variables, BDmofieid, pH, POM-C/H, and RES, were significantly correlated with leaf chlorophyll content and tree vigor (P < 0.05). Using a multiple regression analysis, the newly suggested set of soil variables, including the BDmodified, soil pH, POM-C/H, and soil respiration, showed high predictive power for the growth of urban roadside trees. Future studies should apply these variables to other cities or broader areas and confirm their predictive ability regarding the health of roadside trees.

Historically, much of the New England landscape was converted to pasture for grazing animals and harvesting hay. Today, consumer demand for local, sustainably produced food, the number of livestock farms and the land area used for farming are increasing in Rhode Island. In order to make sound management decisions, it is important to characterize the effects of livestock on the quality of pasture soils. Although pastures remain a fairly common part of the New England landscape, little research has been published on the effects of grazing animals on pasture soil quality. To assess this, I examined soil quality in farms raising beef cattle, sheep, and horses, using hayed pastures as a control. All pastures were situated on ablation till. Three pastures per livestock type and three control hayed pastures were sampled in May, August and October 2012. I interviewed farmers about their management practices, made soil profile descriptions to a 50-cm depth, and characterized vegetation species. I established a 10 m × 10 m sampling area in each pasture and assessed soil quality based on measurement of physical (aggregate stability, bulk density, soil organic matter, infiltration, soil structure, texture and penetration resistance), chemical (soil pH, electrical conductivity, extractable N and P) and biological (active C, earthworm numbers, soil respiration) parameters, according to general agricultural recommendations in the Cornell Soil Health Training Assessment Manual. The effects of livestock type and sampling date on soil quality parameters were analyzed using a one-way ANOVA on ranks. Penetration resistance, bulk density, aggregate stability, organic matter content and extractable phosphate differed significantly (P&lt;0.05) among pasture type. Hay and sheep pastures had significantly lower penetration resistance and bulk density than horse or beef pastures, whose values were in the ideal range for bulk density, but in the acceptable and problematic ranges for surface penetration resistance, according to general agricultural recommendations. For aggregate stability, hay pastures had the highest fraction of water-stable aggregates, followed by sheep and beef pastures, though all values for all pastures fell within the ideal range for agricultural soils. Horse and hay farms had significantly lower extractable phosphate concentrations than beef or sheep farms, with approximately 25% of horse pasture values within the problematic ranges for soil phosphate, according to agricultural soil guidelines. The remaining soil quality parameters (active C, vegetation, electrical conductivity, pH, extractable N, infiltration rate, and earthworm numbers) did not vary significantly among pasture types or season. Soil pH and extractable NO3- values were problematic in all pasture types, whereas values for surface penetration resistance, active carbon levels, vegetation and earthworm counts were problematic in beef and horse pastures. Extractable PO43- was problematic in all pastures except hay. Penetration resistance and bulk density values were inversely correlated with organic matter content, aggregate stability and earthworm counts, whereas soil respiration was correlated with temperatures and soil moisture.\nOverall mean soil quality values, calculated by converting values for each parameter to a % score and calculating the mean % score, were highest for hayed pastures (78), followed by sheep (74), with horse pastures having the lowest soil quality score (69), which was similar to that for beef pasture (70). Pasture soils generally sustain the greatest damage from traffic during wet conditions, which may explain why soil quality was lower in continuously grazed pastures, regardless of soil moisture conditions, whereas hay is generally harvested in warmer months when soil and vegetation are fairly dry. In addition, sheep are smaller than either horse or beef cattle, and exert less pressure per hoof print, which may lead to better soil quality in pasture. Soil quality could be improved in all pastures by liming soil, preventing traffic during wet soil conditions, and preventing overgrazing by rotating animals off pasture when vegetation height is reduced to 7-12 cm. By implementing these practices, farmers can address a variety of physical, biological and chemical soil quality issues, ultimately leading to better pasture production, which could lower animal feed costs considerably.\nThe results of my study provide baseline data on the effect different types of livestock have on pasture soil quality in Rhode Island, which may be useful in making sound land use and agricultural management decisions.

Experimental assessment of ecological restoration options for compacted forest soils

Soil property variation within an aridisol in Big Bend National Park, Texas, USA

This study analyzed relationships between soil properties and food crop production in Ebonyi State of southeast Nigeria. Free survey was conducted after three zones (Agbaja, Akaeze and Ikwo) in the state were purposely selected for representation of the soil sampling. Two types of sampling were conducted; Auger sampling at 0 - 20 and 20 - 40 cm depths and soil profile sampling. Annual crop yield data on maize and cassava for the state from 1988 to 2017 were collected from Agriculture Development Program. Variations in properties among soil horizons were obtained using coefficient of variations while soil parameters were regressed against crop yields to establish their relationships. Results showed that fine sand, total sand, bulk density, total porosity, soil pH, and available phosphorus significantly (p = 0.05) differ from 0 - 20 cm and 20 - 40 cm depths. Also, cassava yield correlated negatively with base saturation, and organic matter at 0.05 probability level; with exchangeable Ca and Na at 0.01 probabilities level but correlated positively with bulk density and available water capacity at 0.01 and 0.05 probability levels, respectively. Similarly, maize yield correlated negatively with available phosphorus and total nitrogen at 0.05 probability level; and with total porosity and exchangeable Ca at 0.01 probability level; and then correlated positively with available water capacity, and bulk density, at 0.01 probability level; with coarse sand at 0.05 probability level. However, soils of Ebonyi State are fertile but some of the chemical properties are still low, therefore, it is paramount to improve the quality of the soil to achieve improved food security in the state.

Rice (Oryza sativa L.)-wheat (Triticum aestivum L.) a dominant cropping system in Punjab Region, Northwestern India, overtime is believed to have negative effect on the soil and water quality. The present study was conducted in an ongoing long-term experiment at the research farm of the School of Organic Farming, Punjab Agricultural University, Ludhiana, to compare the effect of different cropping systems on soil physico-chemical properties. Ten treatments (cropping systems) were laid in a Randomized Complete Block Design (RCBD). The treatments were rice-wheat (CS1), maize-wheat (CS2), basmati rice-wheat-cowpea green manure (CS3), maize-mustard-cowpea green manure (CS4), maize-potato-spring groundnut (CS5), maize-peas-spring groundnut (CS6), maize+ cowpea (fodder)-maize fodder-oats fodder-sathi maize fodder (CS7), sorghum multicut fodder-barseem fodder (CS8), maize (cobs/fodder)-potato-onion (CS9), and baby corn-potato-okra (CS10). Soil samples were collected from four soil depths (0-7.5, 7.5-15, 15-22.5, and 22.5-30 cm) under each cropping system and analyzed for particles size, soil pH, EC, soil organic carbon, aggregate associated carbon, bulk density, porosity, water stable aggregates, MWD, and penetration resistance. Significantly lower soil pH was reported in CS4 and CS8 compared to other cropping systems. Soil EC was significantly higher in CS5 and CS10 while lowest in CS4. Soil organic carbon (SOC), aggregate-associated carbon (AAC), and mean weight diameter (MWD) were significantly higher in CS7 and CS4. Soil bulk density (BD) and penetration resistance (PR) were significantly higher in CS1 and lowest in CS4. SOC was 19% higher in CS7 and BD was 16% lower in CS4 compared to CS1. Soil porosity and water-stable aggregates (WSA) were also found significantly higher in CS4 and CS7 whereas lowest in CS1. The increase in soil depths significantly increased the soil pH, BD and PR, whereas decreased the soil EC, SOC, AAC, porosity, MWD, and WSA. The cropping systems (CS4, CS7, CS8, CS6, CS5, CS3) with green manure/legume/fodder crops in rotation resulted in better physico-chemical properties through the addition of organic matter to the soil compared to cereal-cereal rotations.

This study examines the impact of acidic soil conditions, specifically at pH 4.0, on the proximate and elemental composition of Phaseolus lunatus (Lima bean) and the effectiveness of agricultural lime and organic manure as soil amendments. The experiment was laid in a 1×1×4 factorial and data for all parameters were analyzed using analysis of variance. Growth on the simulated acid soil was achieved by irrigating soil with acidified water, simulated by mixing sulphuric and nitric acids in a 2:1 ratio. The simulated acid soil was subsequently treated with agricultural lime and organic manure prior to planting, with 50 g of each amendment mixed with 5 kg of each soil. Proximate such as moisture content, protein, fat, fiber, and ash, while macro and micronutrient contents in the harvested beans were carried out. Results of physico-chemical properties revealed that acidic soils amended with a combined treatment of agricultural lime and organic manure improved the soil pH towards neutrality (from 4.0 to 7.65). Mineral nutrients analysis revealed a significant (P&lt;0.05) improvement in content for P. lunatus grown on soils amended with organic manure and a combination of agricultural lime and organic manure. The mineral composition was comparable, calcium was significantly (P&lt;0.05) higher in Lima beans grown on unamended acidic soils (pH 4.0) with values ranging from 2022.3% to 5962.3% compared to amended soils values of 1326.3 % to 1381.3%. The application of agricultural lime effectively raised soil pH and improved the nutrient composition of the beans, while organic manure enhanced nutrient availability and improved overall plant health. The combined application of both amendments resulted in the highest nutritional values, indicating a synergistic effect in ameliorating the negative impacts of soil acidity. P. lunatus had higher carbohydrates and moisture content (p&lt;0.05) under the different amended soils. The results of the elemental composition revealed that P. lunatus is rich in macro and micro nutrients. This study has shown the importance of appropriate soil management strategies for enhancing the nutritional quality of Phaseolus lunatus in acid induced soil. The study also revealed that these amendments not only enhanced the nutrients composition of Phaseolus lunatus but also positively impacted the soil physico-chemical properties and nutrients availability.

Maize (Zea mays L.) production in Africa is threatened by the invasive fall armyworm – FAW (Spodoptera frugiperda), and information on its agro-ecological variation and adaptation of different maize cultivars is scarce. The effect FAW was assessed on three hybrid maize cultivars (PAN–12, PAN–53, CMS–8704) and one Landrace in two agro-ecological zones (Coastal Lowland and Western Highland) of Cameroon. Maize cultivars were not fully resistant to FAW feeding and differences occurred in infestation severity and damage incidence between hybrid cultivars and landrace, but no significant yield differences was recorded. FAW infestation severity (IS) and damage incidence (DI) differed (P&lt;0.001) significantly between cultivars in each agro-ecological zone. The highest IS occurred in hybrid maize cultivars as compared to the Landrace. Maize DI differed between cultivars in the Coastal Lowland with the highest in hybrid PAN–12 and PAN–53 as compared to CMS–8704 and Landrace (P&lt;0.001). For the Western Highland, the highest damage incidence occurred in hybrid PAN–53 with the lowest in Landrace (P&lt;0.05). Maize yield differed (P&lt;0.001) significantly across cultivars within each agro-ecological zone. Significantly (P&lt;0.001) higher maize yield occurred in the Coastal Lowland (ranging from 4.2−5.5 tons/ha) as compared to the lowest in the western highland (ranging from 3.2−4.6 tons/ha). The highest yield occurred in PAN–12 and PAN–53 as compared to CMS–8704 and Landrace for each agro-ecological zone. Overall, maize yield could not be predicted from FAW damage since the maize hybrids PAN–12 and PAN–53 recorded the highest damage and the highest yield, which implies high cultivar-specific defensive and yield-producing traits than the effect of FAW damage.

This experiment was carried out at student’s experimental field, Kabba College of Agriculture, Horticultural Section to investigate the response of tomato variety (Roma F) yield to different mulch materials and staking. A split plot experiment was laid out in a randomized complete block design (RCBD) with three replications to randomize the staking levels and mulch materials in the main and sub-plots, respectively. The experiment comprised of two staking levels, i.e. stick staking (SST) and no- stick staking (NST) and six mulch materials, i.e. black polyethylene, white polyethylene, maize straw, palm fronts, grasses and no mulch. The parameters taken on soil physical and chemical properties are soil moisture content (%), soil temperature (O C), soil pH, total nitrogen, available phosphorus and soil organic matter. Growth and yield parameters taken are as follows: average plant height, number of leaves, and number of fruits, stem girth, number of fruit per plant, fruit length, fruit diameter and yield per land area. Weeds were identified and their dry weights were measured. Data were collected from ten randomly selected plants in each plot. The data were statistically analyzed using GENSTAT. The analysis of variance (ANOVA) was performed to find out the significance of variation among the treatments while the significant difference between mean treatments were separated using Duncan’s multiple range test (DMRT) at 5% level of probability. The result obtained from this study indicated that mulch materials and stick staking affect significantly growth parameters of tomato, yield per plant and yield per land area. The result also, indicated that plot mulch with black polythene performance best in terms of growth and yield and also improved soil physical properties better than either white polythene or organic mulch in the study area. It is therefore recommended that black polyethylene should be used as mulch materials for tomato production. However, better and stable fruit yield of tomato could be obtained with the practice of mulching in combination with staking. It is recommended that mulching should be carried out together with staking for higher fruit yield and black polyethylene should be use as mulch material in the study area.

Analysis of effect of bentleg opener geometry on performance in cohesive soil using the discrete element method

In the Amazon region, pastures are the main land use subsequent to deforestation and this change can result in soil acidification and degradation. Liming is a management practice to increase soil pH, important to recover degraded lands and increase soil fertility, but its impacts on soil methane cycling in tropical soils are unknown. Here we investigate the role of soil pH on methane uptake under high concentrations of the gas, manipulating pasture and forest soils pH by liming and evaluating the active methane cycling microbial community. Top layer of forest and pasture soils were subjected to liming treatment and incubated with ∼10 000ppm of 13CH4. Soil DNA was evaluated with Stable Isotopic Probing (SIP-DNA), methanotrophic abundance was quantified (pmoA gene), and high throughput sequencing of 16S rRNA was performed. Liming increased the methane uptake in both forest (∼10%) and pasture (∼25%) soils. Methanotrophs Methylocaldum spp. (type I) and potential methanotrophs in Beijerinckiaceae (type II) were identified to actively incorporate carbon from methane in limed pasture soils. In limed forest soils, Nitrososphaeraceae were identified as 13C-enriched taxa, indicating that ammonia oxidizers can oxidize methane in these soils. Liming Amazonian pasture soils not only contributes to the fertility and recovery of degraded areas but also has the potential to improve the oxidation of methane at high concentrations of this gas.

Spatial variability of soil physical properties in Archeological Dark Earths under different uses in southern Amazon

Soil acidity is one of the major constraints limiting crop productivity in Central Uganda. Thus, the ideal soil pH for crop production ranges from 5.5 to 6.8, but in Central Uganda, crops are believed to be cultivated in soils with pH below these ranges. Given the adverse effects of soil acidity to agricultural production, appropriate measures such as the use of lime could be an option to improve the productive capacity. Henceforward, soils were sampled from farmers’ fields in Mpigi, Mubende and Wakiso Districts representing Central Uganda to evaluate rates of CaCO3 and corncob biochar in a greenhouse incubation study. Afterwards, 2 kg of soil was weighed, placed in a plastic container and thoroughly mixed with 0, 1, 3 and 5 g equivalent to 0, 1, 3 and 5 tons/ha CaCO3 and corncob biochar. Soils were arranged in a Complete Randomized Design (CRD) and moistened with 500 ml of water to bring it to about field capacity and pH determination done for a period of three (3) months until equilibration. The analysis of variance (ANOVA) showed significant effect (P&lt;0.001) on soil pH when CaCO3 and corncob biochar were applied with the three districts recording a near neutral pH of 6.7.&#x0D; After pH equilibration in the greenhouse, rates of CaCO3 and corncob biochar that raised the soil pH in each medium were used to calculate the lime rates i.e., 0, 120, 360 and 600 g applied in the fields. In a Complete Randomized Design (CRD) consisting of four replications, soybean varieties were applied as the main plots while rates of CaCO3 and corncob biochar were applied as the sub plots. The analysis of variance (ANOVA) showed that CaCO3 had significant effect (p&lt;0.001) on soil pH with Mpigi recording the highest soil pH (6.7) followed by Mubende (pH 6.6). Rates of CaCO3 and corncob biochar also showed significant effect (p&lt;0.001) on soybean grain yield compared to 0 g CaCO3 and corncob biochar. Application of 600 g of corncob biochar showed significant effect (p&lt;0.001) on soil pH in the different study locations. Besides, increased in CaCO3 rate to 600 g recorded the highest (7137.5 kg ha-1) soybean grain yield in Wakiso District while 600 g of corncob biochar recorded the highest (5637.5 kg ha-1) soybean grain yield in Mpigi District thus signifying the potential effect of CaCO3 and corncob biochar in Acid Ferralsols.