Incorporation Of Farmyard Manure Research Articles

Yield, water, and carbon footprint of rainfed rice production under the lens of mid-century climate change: a case study in the eastern coastal agro-climatic zone, Odisha, India.

Water and carbon footprint assessment can be a good indicator of sustainable agricultural production. The present research quantifies the potential impact of near-future (2026-2050) climate change on water footprint (WF) and carbon footprint (CF) of farm-level kharif rice production of three locally grown varieties (Khandagiri, Lalat, and Swarna) in Odisha, India, under the two RCP scenarios of 4.5 and 8.5. The crop yield, water resources utilization, and greenhouse gas (GHG) emissions were estimated using the calibrated and validated DSSAT crop simulation model. The precipitation and temperature estimates from three regional climate models (RCM), namely HadGEM3-RA, RegCM4, and YSU-RSM were downscaled using the quantile mapping method. The results revealed a considerably high increase in the total WF of the Khandagiri, Lalat, and Swarna rice varieties elevating up to 101.9%, 80.7%, and 71.8% respectively during the mid-century for RCP 4.5 scenario, and 67.3%, 66.6%, and 67.2% respectively for RCP 8.5 scenario relative to the baseline WF. Moreover, compared to the green WF, the blue WF was projected to increase significantly (~ 250-450%) in the future time scales. This could be attributed to increasing minimum temperature (~ 1.7°C) and maximum temperature (~ 1.5°C) and reduced precipitation during the rice-growing periods. Rice yield was projected to continually decline in the future period (2050) with respect to the baseline (1980-2015) by 18.8% and 20% under RCP 4.5 and 8.5 scenarios respectively. The maximum CF of Swarna, Lalat, and Khandagiri rice were estimated to be 3.2, 2.8, and 1.3 t CO2eq/t respectively under RCP 4.5 and 2.7, 2.4, and 1.3 t CO2eq/t respectively under RCP 8.5 scenario. Fertilizer application (40%) followed by irrigation-energy use (30%) and farmyard manure incorporation (26%) were the three major contributors to the CF of rice production. Subsequently, management of N-fertilizer dose was identified as the major mitigation hotspot, simultaneously reducing carbon footprint and grey water footprint in the crop production process.

Residual Effect of Organic and Inorganic Fertilizers on Growth, Yield and Nutrient Uptake in Wheat under a Basmati Rice–Wheat Cropping System in North-Western India

Restoring soil fertility in farming systems is essential to sustain a crop and its productivity. Thus, the present study was conducted to assess the residual effects of the combined application of fertilizers and manures on yield, concentration and uptake of nutrients in wheat under basmati rice-wheat cropping system. The treatments applied in the present study involve T1: control, T2: farmyard manure (15 t ha−1), T3: poultry manure (6 t ha−1), T4: press mud (15 t ha−1), T5: rice straw compost (6 t ha−1), T6: farmyard manure (15 t ha−1) + 50% recommended dose of nitrogen (RDN), T7: poultry manure (6 t ha−1) + 50% RDN, T8: press mud (15 t ha−1) + 50% RDN, T9: rice straw compost (6 t ha−1) + 50% RDN, T10: 75% RDN, T11: farmyard manure (15 t ha1) + 75% RDN, T12: poultry manure (6 t ha−1) + 75% RDN, T13: press mud (15 t ha−1) + 75% RDN, T14: rice straw compost (6 t ha−1) + 75% RDN, T15: 100% RDN. The residual effects of organic manures significantly improved the growth parameters and yield attributes. Among different residual treatments, the use of farmyard manure + 75% NPK showed maximum plant height (125.2 cm), number of tillers (68.0 m−1), chlorophyll content (45.0) and yield (50.84 q ha−1 for grain and 80.43 q ha−1 for straw, respectively). Additionally, the incorporation of farmyard manure + 75% RDN demonstrated the highest uptake of nitrogen, phosphorus and potassium in grain (7.37, 3.31 and 4.93 g ha−1, respectively) and straw (1.72, 1.05 and 12.63 g ha−1, respectively). The maximum zinc, copper, iron and manganese concentrations were observed to be 32.0, 3.1, 52.1 and 17.6 mg kg−1 in grain and 8.2, 2.1, 374.6 and 20.5 mg kg−1 in straw, respectively. Similarly, the highest uptakes were observed to be 67.6, 15.5, 263.8 and 89.6 g ha−1 in grain and 173.3, 16.8, 3026.9 and 170.6 g ha−1 in straw, respectively. Thus, the integrated application of farmyard manure with 75% RDN could be used to sustain wheat productivity and maintain soil fertility which otherwise deteriorates due to the sole application of inorganic fertilizers.

Role of Organic Amendments to Mitigate Cd Toxicity and Its Assimilation in Triticum aestivum L.

In soil biota, higher and enduring concentration of heavy metals like cadmium (Cd) is hazardous and associated with great loss in growth, yield, and quality parameters of most of the crop plants. Recently, in-situ applications of eco-friendly stabilizing agents in the form of organic modifications have been utilized to mitigate the adverse effects of Cd-toxicity. This controlled experiment was laid down to appraise the imprints of various applied organic amendments namely poultry manure (PM), farmyard manure (FYM), and sugarcane press mud (PS) to immobilize Cd in polluted soil. Moreover, phytoavailability of Cd in wheat was also accessed under an alkaline environment. Results revealed that the addition of FYM (5–10 ton ha-1 ) in Cd-contaminated soil significantly increased germination rate, leaf chlorophyll content, plant height, spike length, biological and grain yield amongst all applied organic amendments. Moreover, the addition of FYM (5–10 ton ha-1 ) also reduced the phytoavailability of Cd by 73–85% in the roots, 57–83% in the shoots, and 81–90% in grains of wheat crop. Thus, it is affirmed that incorporation of FYM (5–10 ton ha-1 ) performed better to enhance wheat growth and yield by remediating Cd. Thus, the application of FYM (5–10 ton ha-1 ) reduced the toxicity induced by Cd to plants by declining its uptake and translocation as compared to all other applied organic amendments to immobilize Cd under sandy alkaline polluted soil.

Improvement of Maize Productivity and N Use Efficiency in a No-Tillage Irrigated Farming System: Effect of Cropping Sequence and Fertilization Management.

The sequence of the preceding crops in a no-tillage farming system, could interact with the integrated use of mineral and organic nitrogen (N) sources in a way that improves the growth and productivity of the terminal maize crop, meanwhile, enhancing its N use efficiency (NUE). In the current study, six legume-cereal crop sequences, including faba bean, soybean, Egyptian clover, wheat, and maize were evaluated along two experimental rotations that ended up by planting the terminal maize crop. In addition, the effects of applying variable mineral nitrogen (MN) rates with and without the incorporation of farmyard manure (FYM) on the productive performance of maize and its NUE were tested. The field experiments were conducted in a no-tillage irrigated farming system in Northern Egypt, a location that is characterized by its arid, Mediterranean climate. Results revealed that increasing the legume component in the evaluated crop sequences, up to 75%, resulted in improved maize ear leaf area, 1000-grain weight, and harvest index, thus, a higher final grain yield, with the inclusion of Egyptian clover was slightly better than faba bean. Comparing the crop sequences with 50% legume contribution uncovered the positive effects of soybean preceding crop on the terminal maize crop. Substituting 25% of the applied MN with FYM resulted in similar maize yields to the application of the equivalent 100% MN rates. The fertilizer treatments significantly interacted with the crop sequences in determining the maize grain yield, where the highest legume crop contribution in the crop sequence (75%) equalized the effects of the different fertilizer treatments on maize grain yield. The integrated use of FYM with MN in maize fertilization improved the NUE compared to the application of MN alone. Comparing fertilization treatments with similar MN content, with and without FYM, revealed that the difference in NUE was attributed to the additional amount of FYM. In similar conditions to the current study, it is recommended to grow faba bean two years before maize, while Egyptian clover could be grown directly preceding maize growth, with frequent inclusion of soybean in the sequence, this could be combined with the application of an average of 200 kg MN ha−1 in addition to FYM.

Effect of long-term crop rotation and fertilisation management on soil humus dynamics in organic and sustainable agricultural management systems

The integration of organic fertilisers into agricultural practices is one approach to enable more efficient agricultural management systems to decrease adverse environmental impacts of agriculture. In this context, the objective of this research was to determine the impact of long-term crop rotation and organic and mineral fertilisation on soil humus content, humic and fulvic acids, organic matter humification in organic and sustainable agricultural management systems with low (1.90–2.01%) and moderate (2.10–2.40%) initial humus contents. Long-term field experiments with different agricultural management systems started in 1960 at the Lithuanian Research Centre for Agriculture and Forestry and soil humus dynamics experiments were conducted from 2006 to 2017. Results of the long-term use of organic and sustainable agricultural management systems with different crop rotations and fertilisation revealed the positive effect of the applied supplies on soil humus, especially for farmyard manure in combination with green manure. The incorporation of farmyard manure and biomass of white mustard resulted in a lower degree of humification when compared to green manure alone, green manure + mineral N, and farmyard and green manure + mineral N. In the low humus content soil, the degree of humification under all agricultural management systems was significantly improved, on average by 0.9% compared to soil with a moderate humus content.

Leaching of Clothianidin in Two Different Indian Soils: Effect of Organic Amendment.

Clothianidin is a widely used insecticide under Indian subtropical condition. The objective of this study was to generate residue data which aims to understand leaching potential of clothianidin [(E)-1-(2-chloro-1,3-thiazol-5-ylmethyl)-3-methyl-2- nitroguanidine] through packed soil column. The maximum amount of clothianidin was recovered at 0-5cm soil depth in both Manipur (67.15%) and Delhi soil (52.0%) under continuous flow condition. Manipur and Delhi soil concentrated maximum residue with or without farm yard manure (FYM) in 0-20cm soil depth. The effect of varying the amount of water enhanced the distribution of residues in the first 0-5cm layer. Among the tested soils, residue was detected in the leachate from Delhi soil (0.04µg/mL). Clothianidin leaching was minimized in soil of Manipur compared to Delhi after incorporation of FYM. As the volume of water increased upto 160mL, mobility increased and residues moved to lower depth. Clothianidin did not leach out of the 25cm long soil columns even after percolating water equivalent to 415.42mm rainfall. Clothianidin is mobile in soil system and mobility can be reduced by organic amendment application.

Production and management of cattle manure in the UK and implications for land application practice

AbstractA review of livestock and manure management across the UK was undertaken as part of a wider study of important factors impacting on greenhouse and other gaseous emissions from agriculture. All major livestock sectors were covered by the review, but only data on cattle manure are reported in this study. Cattle manure comprises 67 Mt (80%) of the total 83 Mt of UK annual livestock manure production during the housing period. Overall, about 47% of total UK cattle manure production was estimated to be as undiluted slurry and 53% as solid, mainly straw‐based farmyard manure (FYM). Survey data suggested important regional differences in cattle manure management across the UK; examples include the predominance of slurry in SW Scotland, N Ireland and to a lesser extent, in Wales, compared to the continued importance of straw‐based FYM systems in England. Survey data on land application of manures from the British Survey of Fertiliser Practice (BSFP) generally showed the expected distribution of cattle manure application timings, dominated by crop sowing/establishment or growth patterns. However, in recent years, an apparent increase in land spreading in February–April, with less application in November–January is encouraging, the trend towards spring/early summer spreading of cattle slurry suggesting greater appreciation of its value as a nutrient source. BSFP returns on manure application techniques have also shown increasing uptake of shallow injection of cattle slurry, from <1% (2004) to 10% (2013) and for increasing rapid (<6 h) incorporation of FYM, from 3% (2007) to 14% (2013).

Synergistic and antagonistic interactions among organic amendments of contrasted stability, nutrient availability and soil organic matter in the regulation of C mineralisation

Organic amendments to agricultural soils may increase soil organic matter reserves. However, manure amendment may stimulate soil microbial activity and soil organic matter decomposition. The stability of manure and soil organic matter and the availability of nutrients are crucial for the regulation of soil organic matter decomposition. Therefore, we aimed to study the effects of adding stabilised or unstabilised manures combined with mineral nutrients (N–NO3, P–PO4, K and S–SO4) on carbon mineralisation in two agricultural (sandy loam) soils with contrasted organic matter stocks and N availability. These two soils were incubated alone and after adding unstabilised farmyard manure (FYM) or stabilised manure (compost), combined with the addition of mineral nutrients. Mineralisation of C (CO2 evolution) increased after FYM addition while it decreased after compost addition as compared to the control soils. When mineral nutrients were added to soils amended with FYM, C mineralisation synergistically increased only in soils with low nitrogen availability. In these soils, the addition of nutrients may promote the mobilization of soil C, while in soils with high N availability the synergistic mobilization of C on adding FYM may be reduced. In contrast, the depressed C mineralisation after the addition of compost was little affected by nutrient availability. We suggest that recalcitrant compounds in compost may be stabilised in soil particles and humic substances with little effects of nutrient availability. In contrast, the incorporation of FYM was mainly driven by microbial transformations and affected by nutrient availability. Finally, we conclude that the application of stabilised organic matter may be a good practice for the built up of humus in a wide range of arable lands with particular significance for land reclamation in organic matter depleted soils.

Nutrient Recycling and Its Relationship with Biofertility Indicators of Soil Health and Nutrient Uptake in a Rice (Oryza sativa L.)-Wheat (Triticum aestivumL. emend. Fiori & Paol) Cropping Sequence

The effect of nutrients recycled through the incorporation of farmyard manure, crop residue, and green manure was studied in the Indo-Gangetic plain of India during 2006 to 2009. The biofertility indicators such as soil health, uptake of nutrients by the crops, yield, and yield attributes were studied in the cropping sequence of rice (Oryza Sativa L.)-wheat (Triticum aestivum L. emend. Fiori & Paol). The recycling of organic residues is evident from the results as the values of soil microbial biomass carbon (364.0 μg/g soil) and carbon dioxide evolution (1.75 μg/g soil/h) were recorded. The results show that dehydrogenase and phosphatase enzymes activities have increased significantly after 3 years as a result of the incorporation of residue plus green manure. The mean yield data of rice and wheat crops revealed that incorporation or burning of residue in the field resulted in a slightly higher yield over residue removal. Further, higher grain yield (rice = 7.54 t/ha, wheat = 5.84 t/ha) was recorded in residue plus green manuring treatment. Total uptake of the nutrients by rice–wheat crops in sequence was highest (N 203.70, P 37.20, K 203.60 kg/ha) in case of crop residue plus green manuring treatment.

Microbial biomass P dynamics and sequential P fractionation in high and low P fixing Kenyan soils

We tested how the incorporation of farmyard manure (FYM) and inorganic phosphorus (P), KH2PO4 fertilizer changed soil microbial biomass phosphorus (biomass Po and inorganic and organic P fractions) in high and low P fixing Kenyan soils. Four soil treatments were compared during 32 weeks of laboratory incubation: (i) Nil; (ii) FYM (10 g kg−1); (iii) KH2PO4 (2.5 g kg−1) (P); and (iv) FYM (10 g kg−1) + KH2PO4 (2.5 g P kg−1). Biomass P was determined by fumigation-extraction followed by resin extraction, and P availability determined using a modified Hedley P fractionation method. The addition of FYM + KH2PO4 only increased biomass P in the high P fixing soil. From a maximum of about 22.5 μg P g−1 soil (week 1), biomass P declined to 4.8 (week 2), increased steadily to week 16 (15.2), and then decreased to 9.7 μg P g−1 soil (week 32). Biomass P in the low P fixing soil, with higher fertility, resin P and organic matter concentrations did not show any significant change. The P fractions that changed the most relative to the control, were the resin, Po–HCO3 and P–OH (week 1 and 16). This difference was enhanced in the high P fixing soil but resin P was the same in that soil at week 16, and the reduction in Po–OH in the FYM + KH2PO4 treatment (162.4 μg P g−1) compared to the control (242.2 μg P g−1) was more pronounced. This indicates an enhancement of microbial activity in the high P fixing soil.

Soil aggregation and distribution of carbon and nitrogen in different fractions after 41 years long-term fertilizer experiment in tropical rice–rice system

Inorganic fertilizers and manure application can alter the aggregate distribution as well as aggregate associated organic carbon and nitrogen. It is not fully understood how long term addition of carbon (C) and nitrogen (N) through biomass, farm yard manure (FYM) and inorganic fertilizers are distributed in soil aggregates in a tropical rice–rice system. Therefore, the objectives of this study were to investigate the long-term effects of FYM and inorganic fertilizer in a rice–rice system on (i) distribution of water stable aggregates in the soil, and (ii) amount of total soil organic carbon (TOC), total N and C/N ratio in different aggregate fractions. The total water stable aggregates (WSA) ranged from 71.6% under control to 91.1% under NPK+FYM in the surface soil (0–15cm). The incorporation of FYM increased the macroaggregates (5–2mm) by 165.3% and mesoaggregates by 130.7% (2–1mm) and 282.8% (1–0.5mm) over control in 0–15cm soil layer. Mean weight diameter (MWD), varied from 0.43 to 0.78 in 0–15cm and from 0.40 to 0.72 in 15–30cm soil layer. MWD was higher under FYM treated plots than inorganic fertilizer alone and unfertilized control plots. Irrespective of treatment, macroaggregates (5–2mm) had the highest (4.13–14.03gkg−1) and microaggregate fraction (0.25–0.1mm) had the least (3.70–8.89gkg−1) TOC content in the 0–15cm soil layer. The application of FYM either alone or in combination with inorganic fertilizers significantly increased the accumulation of TOC in all aggregate fractions over control, however, the effect was more pronounced in macroaggregates fraction 5–2mm and microaggregate fraction 0.1–0.053mm. The combined application of inorganic fertilizers and FYM resulted in an increase in total N content which ranged from 0.43 to 1.0gkg−1 in 5–2mm and from 0.09 to 0.44gkg−1 in 0.25–0.1mm aggregate fractions. The highest C:N ratio was recorded in aggregate fraction of 0.1–0.053mm irrespective of treatment, whereas aggregate fraction of 0.5–0.25mm had the least C:N ratio. A higher C:N ratio was observed in 15–30cm than 0–15cm soil layer. Hence it was concluded that the long-term application of FYM resulted in C and N accumulation in bulk soil and aggregates, but the accumulation pattern was dependent on aggregate size.

Effects of weed management practices on enteric pathogen transfer into lettuce ( Lactucasativa var. capitata)

We evaluated the effect of using farmyard manure (FYM) in combination with four weed control techniques on the hygienic quality of lettuce. Treatments with six replications included the application of fresh FYM on the soil combined with hand-hoeing (assumed high-risk) and fresh FYM incorporation combined with plastic mulch (assumed low risk). The experiment was repeated twice per season over two years at Bonn University, Germany. The amounts of enteric bacteria in all treatments were within the acceptable limits. Enterococcus was detected in the majority of the samples in concentrations up to 3.7 log 10 CFU/g. The Escherichia coli contents of lettuce ranged between n.d. and 10 3 CFU/g. There was no consistent effect suggesting a specific risk linked to one of the experimental treatments. We conclude that weeding techniques did not increase the risk of exposure to E. coli when FYM is used for fertility in organic production systems.

Persistence and management of dinitroaniline herbicides residues in sandy loam soil

The addition of organic manure affects the biological, chemical and physical properties of soil that control the fate of herbicides. Three dinitroaniline herbicides were studied to asses their persistence, dissipation and residue management in sandy loam soil with and without addition of farmyard manure (FYM) under middle western Indian agro-climatic conditions. The herbicides, pendimethalin [N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine], trifluralin [2,6-dinitro-N,N-dipropyl-4-(trifluoromethyl) benzenamine] and fluchloralin [N-(2-chloroethyl)-2,6-dinitro-N-propyl-4-(trifluoromethyl) benzenamine], were applied at a rate of 0.5 and 1.0 kg ha−1 as a pre-plant incorporation in the field, cropped with Indian mustard (Brassica juncea L.). FYM incorporation at a rate of 10 t ha−1 decreased herbicide persistence in all the sampling intervals. Relatively lower half-lives of 44.93, 41.81; 41.23, 39.09 and 39.61, 43.00 days, each at the rate of 0.5 and 1.0 kg ha−1, respectively for pendimethalin, trifluralin and fluchloralin were recorded with FYM incorporation. On the other hand, the half-life values in absence of FYM were higher for all three dinitroaniline herbicides used. Dissipation rate of all three dinitroanilines increased progressively with time at both application rates.

Structural Stability of Humid Tropical Soils as Influenced by Manure Incorporation and Incubation Duration

Soil erosion due to the impact of high‐intensity tropical rainfall is one of the important environmental problems in the Republic of Trinidad and Tobago. Organic matter and incubation can increase soil cohesion after soil structure disruption and therefore influence aggregate stability and saturated hydraulic conductivity (Ksat), which are key properties in improving soil and water management. We examined the influence of manure incorporation and incubation duration on the structural stability of three tropical soils with different clay contents and mineralogies. Samples were treated with farmyard manure (FYM) at the rates of 0, 6, and 12% per dry mass of soil, brought to field capacity (FC), and incubated for 56 d at an average temperature and humidity of 26°C and 67.5%, respectively. Subsamples were taken at 14, 28, and 56 d for the determination of water‐stable aggregation (WSA) and Ksat We found an increase in WSA of 23 to 27% for the three soils studied when we compared the natural sample with no treatment to the largest treatment combination (12% FYM and 56‐d incubation). The higher the load of FYM incorporation, the more stable the soil became with incubation. Greater improvement was found in Ksat, whose values increased between 50 and 700%. Also, both WSA and Ksat increased with incubation duration regardless of FYM level or clay content and mineralogy. This suggests that, by itself, soil incubation at FC after structural disturbance, with or without FYM incorporation, is a desirable practice that encourages particle bonding and structural improvement.

Organic based nutrient management strategies: effect on soil nutrient availability and maize (Zea mays L.) performance in Njoro, Kenya.

A field experiment based on the concept of organic nutrient management (ONM) was conducted in Njoro, Kenya to test the effect of improved legume fallows; crotalaria (CR), lablab (LB), garden pea (GP) and natural fallow (NF, as control) on available soil N and P, and maize performance. The experimental layout was a split plot in a randomized complete block design. The main plots were two cropping systems involving the improved legume fallows and NF preceding sole maize and maize bean (M/B) intercrop. The sub-plots were two residue management types; residue incorporation and residue removal with farm yard manure (FYM) incorporated in its place. Incorporation of LB, CR and GP residues resulted in higher concentrations of N and P in soil than NF residue and FYM incorporation in both cropping systems. Under sole maize, grain yield following LB was significantly higher (51, 28.2 and 52%) than after CR, GP and NF, respectively. In the M/B intercrop, maize grain yield following LB was significantly higher (38.5 and 28.5%) than after GP and NF with no significant differences in yields following CR and LB. Maize dry matter (DM) yields followed a similar trend. Overall, maize grain and DM yields were higher in sole maize cropping system than in M/B intercrop with an additional 0.5 - 0.6 kg ha-1 of bean grain yield obtained in the latter cropping system. The improved fallow legumes, with LB being superior, enhanced soil productivity and consequently higher yields of the succeeding crop. The ONM strategy tested is thus a feasible technology that could easily fit into the circumstances of the resource poor farmers within the region. Key words: Biological nitrogen fixation, farm yard manure, improved legume fallow, residue management.

Effect of Organic Residue Management on Soil Hydro-Physical Characteristics and Rice Yield in Eastern Himalayan Region, India

Monocropping of lowland rice is the predominant system in valley land and high-rainfall regions of northeastern India. Recently, the unsustainability of this system has owing to soil structural deterioration and nutrient depletion, become evident, resulting from continuous puddling on the same piece of land even if recommended inorganic fertilizers have been applying regularly. To regenerate and maintain soil structure in rice fields, farmers in this region frequently use farm yard manure (FYM), but low availability of FYM because of its other uses indicates that it could not meet the organic matter requirements of this system. We evaluated the long-term effects of different locally available jungle grasses and weeds on soil hydro-physical properties and rice yield through a 5-year field experiment (2000 to 2005) at the Indian Council of Agricultural Research (ICAR) Complex for North Eastern Hilly (NEH) Region, Umiam, Meghalaya, India and also compared their negative or positive effects with FYM in acidic, Typic Hapludalf soil. The objective was to determine whether locally available grasses (Jungle grass) and weeds (Ambrosia sp.) could be used as alternative sources of organic materials for lowland rice in scarcity of FYM. Results showed that incorporation of FYM or jungle grass or Ambrosia sp., continuously for 5 years in puddled rice soil improved soil organic carbon (SOC) by 21.1%; the stability of micro-aggregates, moisture retention capacity, and infiltration rate of the soil by 82.5, 10, and 31.3%, respectively; and soil bulk density decreased by 12.6%. Application of FYM produced better soil physical environment than that under jungle grass and Ambrosia sp. However, as these grasses and weeds contained higher nutrient levels than FYM and increased the SOC slowly, these organics may serve as alternative to FYM and may have a dramatic effect on long-term productivity of rice. The gradual improvement in soil physical properties led to a significantly higher yield of rice. We conclude that applying organic manure or organic residue annually may mitigate the negative effect of puddling and related properties and therefore could contribute to the sustainability of the wetland rice ecosystem.

Land Use limitations and management option for a Savanna Zone Alfisol

A 50 by 50 m rigid grid survey of part of the Institute For Agricultural Research (IAR) farm in Zaria (11° 10’N and 7°35’E) was carried out to characterize the morphological, physical and chemical properties of soils at the site. Quick crosschecks in areas outside the rigid grid but having seemingly varying soil units was also studied in the field. Two soil units (‘Oxyaquic Vertic Paleustalfs / Gleyic Lixisol’ and ‘Aquic Kandiustalfs / Gleyic Lixisols’) were delineated. Soil samples were obtained from identified horizons of each pedon, air dried, sieved through 2.0mm sieve to obtain sub samples less than 2.0mm for laboratory analysis. Results obtained showed soils of the ‘Oxyaquic Vertic Paleustalfs / Gleyic Lixisol’ to have within its subsoil ‘Argillic’ pedogenetic features, mottling and ‘Gleyic’ properties, and no subsoil acidity problems. The subsoil has increasing clay with depth, and temporary stagnation of water. Soil condition in this unit would however be improved for sustainable crop production by liming and /or incorporation of farmyard manure, contour ridging and construction of field drainage ditches to conduct excess field and subsoil stagnated water away from the fields. Soils of the ‘Aquic Kandiustalfs / Gleyic Lixisols’ have ‘Kandic’ subsoil properties, ‘Gleyic’ and mottled subsoil horizons at shallow depths to the surface horizons, and exchange acidity (H++Al3+) values ranging between 0.6 and 1.4 cmolkg -1, suggesting acid soil problem in this unit. Also, extractable Zn values were very high and could adversely affect growth and production of crops. This problem would be corrected by liming, adequate drainage to remove stagnating subsoil and excess field water, and incorporation of farmyard manure to enhance the soils’ nutrient availability/exchange capacity, control soil acidity build up and improve aeration conditions in the plow layer.

Land Use Limitations and Management Option for a Savanna Zone Alfisol

A 50 by 50 m rigid grid survey of part of the Institute for Agricultural Research (IAR) farm in Zaria (110 10¹N and 7035¹E) was carried out to characterize the morphological, physical and chemical properties of soils at the site. Quick crosschecks in areas outside the rigid grid but having seemingly varying soil units was also studied in the field. Two soil units (‘Oxyaquic Vertic Paleustalfs/Gleyic Lixisol' and ‘Aquic Kandiustalfs/Gleyic Lixisols') were delineated. Soil samples were obtained from identified horizons of each pedon, air dried, sieved through 2.0mm sieve to obtain sub samples less than 2.0mm for laboratory analysis. Results obtained showed soils of the ‘Oxyaquic Vertic Paleustalfs/Gleyic Lixisol' to have within its subsoil ‘Argillic' pedogenetic features, mottling and ‘Gleyic' properties, and no subsoil acidity problems. The subsoil has increasing clay with depth, and temporary stagnation of water. Soil condition in this unit would however be improved for sustainable crop production by incorporation of farmyard manure, contour ridging and construction of field drainage ditches to conduct excess field and subsoil stagnated water away from the fields. Soils of the ‘Aquic Kandiustalfs / Gleyic Lixisols' have ‘Kandic' subsoil properties, ‘Gleyic' and mottled subsoil horizons at shallow depths to the surface horizons, and exchange acidity (H++Al3+) values ranging between 0.6 and 1.4 cmolkg-1, suggesting acid soil problem in this unit. Also, extractable Zn values were very high and could adversely affect growth and production of crops. This problem would be corrected by adequate drainage to remove stagnating subsoil and excess field water, and incorporation of farmyard manure to enhance the soils' nutrient availability/exchange capacity, control soil acidity build up and improve aeration conditions in the plow layer. Keywords : Soil limitations, sub soil drainage, soil and water conservation Nigerian Journal of Soil and Environmental Research Vol. 7 2007: pp. 70-81

The effect on N 2O emissions of storage conditions and rapid incorporation of pig and cattle farmyard manure into tillage land

The use of additional straw in animal housing and the rapid incorporation of manure into tillage land have been recognised as potential techniques to reduce ammonia (NH 3 ) emissions. However, there is the potential for these management practices to increase nitrous oxide (N 2 O) emissions, i.e. 'pollution swapping'. Emissions of N 2 O were monitored during storage of either pig or cattle farmyard manure (FYM) and after application to tillage land at two UK sites. Losses of N 2 O from conventionally stored pig and cattle FYM were 2.6% and 4.3% of the total-N into store, respectively. Following land spreading, N 2 O losses ranged from 0.05) effect of extra straw use during housing on N 2 O emissions following the spreading of pig and cattle FYM. No consistent effect of FYM incorporation on N 2 O emissions was evident suggesting that rapid incorporation (<4h) can only reduce both N 2 O and NH 3 losses under site specific conditions. The results suggest that strategies to minimise N 2 O emissions from solid manure management should focus on storage rather than land spreading, and that there is a need to develop integrated manure management strategies to minimise 'pollution swapping'.

Increase in soil pH due to Ca-rich organic matter application causes suppression of the clubroot disease of crucifers

Clubroot disease of cruciferous plants caused by the soil-borne pathogen Plasmodiophora brassicae is difficult to control because the pathogen survives for a long time in soil as resting spores. Disease-suppressive and conducive soils were found during the long-term experiment on the impact of organic matter application to arable fields and have been studied to clarify the biotic and abiotic factors involved in the disease suppression. The fact that a large amount of organic matter, 400 t ha −1 yr −1 farmyard manure (FYM) or 100 t ha −1 yr −1 food factory sludge compost (FSC), had been incorporated for more than 15 yr in the suppressive soils and these soils showed higher pH and Ca concentration than the disease conducive soil led us to hypothesize that an increase in soil pH due to the long-term incorporation of Ca-rich organic matter might be the primary cause of the disease suppression. We have designed a highly reproducible bioassay system to examine this hypothesis. The suppressive and conducive soils were mixed with the resting spores of P. brassicae at a rate of 10 6 spore g −1 soil, and Brassica campestris was grown in a growth chamber for 8 d. The number of root hair infections was assessed on a microscope. It was found that the incorporation of FYM and FSC at 2.5% (w/w) to the conducive soil suppressed the infection and that the finer particles (⩽5 mm) of FSC inhibited the infection and increased soil pH more effectively. Neutralization of the conducive soil by Ca(OH) 2, CaCO 3 and KOH suppressed the infection, but the effectiveness of KOH was less than those of Ca(OH) 2 and CaCO 3. Acidification of the suppressive soils by H 2SO 4, promoted the infection. The involvement of soil biota in the disease suppression was investigated using the sterilized ( γ-ray irradiation) suppressive soils with respect to soil pH. The γ-ray irradiation promoted the infection at pH 5.5, but no infection was observed at pH 7.4 irrespective of the sterilization status. All these observations suggest that soil pH is a major factor in disease suppression by organic matter application and that Ca and soil biota play certain roles in the suppression under the influence of soil pH.