• Authors:
    • Prasad, J.
    • Challa, O.
    • Mandal, C.
    • Mandal, D. K.
  • Source: Agropedology
  • Volume: 16
  • Issue: 2
  • Year: 2006
  • Summary: The present study used water use efficiency (WUE) as an indicator of land quality index (LQI), through a composite Water Use Efficiency (GMWUE), on the line of land evaluation index of Food and Agriculture Organization. The GMWUE is a multiplicative function of WUE of individual crop/cropping system raised within a micro agro-edaphic environment (AEE). A relative LQI scale has been developed considering LQI for the most productive land as 100 and accordingly the LQI of other land has been fixed. The experimental cropping systems were cotton (sole), sorghum-wheat, soyabean-wheat, sorghum-gram and soyabean-gram for two years under normal rainfall in typical shrink-swell soils of Nagpur district of Maharashtra, India. The soyabean-wheat system had highest water use (WU) of 586.8 to 755.9 mm followed by sorghum-wheat, soyabean-gram, sorghum-gram and sole cotton. The WUE was highest for sole cotton (4.8-11.5 kg ha -1 mm -1) followed by soyabean-gram (3.7-10.16 kg ha -1 mm -1). The LQI in terms of GMWUE was 100 for Vertic Haplustepts occurring in the lower piedmont plain whereas it was 51 for Typic Haplustepts and 48 for Typic Haplusterts representing the upper piedmont and valley plain, respectively.
  • Authors:
    • Yamaguchi, J.
  • Source: JIRCAS International Symposium Series
  • Issue: 13
  • Year: 2006
  • Summary: Involvement in environment issues and population carrying capacity was analysed based on three typical agricultural systems: slash and burn semi-sedentary agriculture, recycling agriculture in which organic materials are re-used, and non-cyclic agriculture in which nutrient supply depends chiefly on chemical fertilizers. Our analysis showed that, due to its high productivity, non-cyclic agriculture is obligatory to support an ever-growing population and to offset the resultant continuous loss of arable land per person. Fertilizers to be applied should be quantified to exactly meet the balance between plant requirements and natural supply. Excess application of fertilizers should always be avoided. Degradation of soils in the tropics is caused mainly by water and wind erosion, and to a lesser extent from nutrient disturbance (mainly from shortages). The environmental protective effects of permanent crops are shown using two examples. One is in Erimo, Hokkaido (Japan), where fishermen have revived their local fisheries by reforesting the coastline, and the other in Tanzania where indigenous people thrive on the permanent culture of bananas. In the tropics, the use of vegetation as soil cover confers advantages in highly fragile areas, if only because of protection from erosion. The introduction of permanent crops is an alternative to establishing co-existence between agriculture and the environment.
  • Authors:
    • Villenave, C.
    • Girardin, C.
    • Blanchart, E.
    • Azontonde, A.
    • Barthes, B.
    • Oliver, R.
    • Feller, C.
  • Source: Soil Erosion and Carbon Dynamics
  • Year: 2006
  • Summary: Field experiment was conducted from 1988 to 1999 at an experimental farm at Agonkanmey, near Cotonou in southern Benin, to study the effect of relay-cropping maize through Mucuna pruriens (var. utilis). The relay-cropping system was compared with traditional maize cropping system without any input, and with a maize cropping system with mineral fertilizers (NPK). Special attention was given on the changes in soil C during the period of the experiment in relation to residue biomass C returned to the soil, runoff and soil erosion losses, and loss of C with erosion. The soils are classified as sandy loam Typic Kandiustult. The general properties of these soils are given. For this soil type, relay cropping of maize and mucuna was very effective in enhancing C sequestration: change in Ct (total C content) stock for 0 to 40 cm depth was 1.3 t C/ha per year over the 12-year period of the experiment, ranging among the highest rates recorded for the eco-region. This increase resulted first from the high amount of residue biomass provided by mucuna, which amounted to 10 t DM/ha per year (83% aboveground). Mucuna residues, supplying the soil with N, also favoured the production of maize biomass, and total mucuna plus maize residue biomass returned to the soil was approximately 20 t/ha per year. In contrast, non-fertilized and fertilized continuous maize cultivation resulted in -0.2 and 0.2 t C/ha per year change in Ct stock for 0 to 40 cm depth, respectively. Total residue biomass was 8 and 13 t/ha per year, including 77 and 29% by weeds, respectively. Thick mulch produced by mucuna decreased losses by runoff and erosion, which were 0.28, 0.12 and 0.08 mm/mm and 34.0, 9.0 and 3.0 t/ha per year in unfertilized, fertilized with NPK and mucuna treatments, respectively. Eroded C was estimated at 0.3, 0.1 and 1.0 t C/ha per year in unfertilized, fertilized with NPK and mucuna treatments, respectively. Through its benefits on soil organic matter management, weed suppression and erosion control, cropping systems including a legume crop may have an adverse impact from a global change standpoint.
  • Authors:
    • Rani, S. S.
    • Pradhan, A. C.
  • Source: Journal of Crop and Weed
  • Volume: 1
  • Issue: 2
  • Year: 2005
  • Summary: A field experiment was carried out during winter seasons of 2002-03 and 2003-04 in Nadia, West Bengal, India to study the effect of chemical methods of weed control in zero-till wheat. The results revealed that the crop was severely infested with sedges and grasses. The pooled analysis showed 50 percent reduction in grain yield due to weed-crop competition. All weed control methods effectively reduced weed density and markedly suppressed dry weight of weeds. Growth parameters of wheat like tiller density, leaf area indices, crop growth rates and yield components (spike density, number of filled grains per spike and test weight of grain) increased significantly by the application of chemicals over weedy control in comparison to others. Application of metribuzin at 175 g ha -1 before first irrigation effectively controlled all categories of weeds in zero-till wheat resulting in 78.2 percent increase in grain production which was comparable with weed free and two manual weedings. Among the chemical control measures, metribuzin 175 g ha -1 before first irrigation was most economical by paying highest net return (Rs. 18 598/-) and benefit-cost ratio (2:1).
  • Authors:
    • Verchot, L.
    • Palm, C.
    • Albrecht, A.
    • Cadisch, G.
    • Mutuo, P.
  • Source: Nutrient Cycling in Agroecosystems
  • Volume: 71
  • Issue: 1
  • Year: 2005
  • Summary: Losses of carbon (C) stocks in terrestrial ecosystems and increasing concentrations of greenhouse gases in the atmosphere are challenges that scientists and policy makers have been facing in the recent past. Intensified agricultural practices lead to a reduction in ecosystem carbon stocks, mainly due to removal of aboveground biomass as harvest and loss of carbon as CO2 through burning and/or decomposition. Evidence is emerging that agroforestry systems are promising management practices to increase aboveground and soil C stocks and reduce soil degradation, as well as to mitigate greenhouse gas emissions. In the humid tropics, the potential of agroforestry (tree-based) systems to sequester C in vegetation can be over 70 Mg C ha-1, and up to 25 Mg ha-1 in the top 20 cm of soil. In degraded soils of the sub-humid tropics, improved fallow agroforestry practices have been found to increase top soil C stocks up to 1.6 Mg C ha-1 yr-1 above continuous maize cropping. Soil C accretion is linked to the structural development of the soil, in particular to increasing C in water stable aggregates (WSA). A review of agroforestry practices in the humid tropics showed that these systems were able to mitigate N2O and CO2 emissions from soils and increase the CH4 sink strength compared to cropping systems. The increase in N2O and CO2 emissions after addition of legume residues in improved fallow systems in the sub-humid tropics indicates the importance of using lower quality organic inputs and increasing nutrient use efficiency to derive more direct and indirect benefits from the system. In summary, these examples provide evidence of several pathways by which agroforestry systems can increase C sequestration and reduce greenhouse gas emissions.
  • Authors:
    • Klepker, D.
    • Yamada, M.
    • Hitsuda, K.
  • Source: Agronomy Journal
  • Volume: 97
  • Issue: 1
  • Year: 2005
  • Summary: Sulfur deficiency symptoms are more often observed in crops at early stages of growth since S can be easily leached from the surface soil. The objectives of this study were to evaluate some of the popular rotation crops grown in Brazil for tolerance to low external S levels and to determine the critical tissue concentration for S deficiency during early stages of growth. Germinated seedlings of soybean [ Glycine max (L.) Merr.], rice ( Oryza sativa L.), maize ( Zea mays L.), field bean ( Phaseolus vulgaris L.), wheat ( Triticum aestivum L.), cotton ( Gossypium spp.), sorghum ( Sorghum bicolor L.), and sunflower ( Helianthus annuus L.) were transferred to water culture with 0.0 to 32.0 mg S L -1 and were grown for 29 d. The minimum S concentration required in nutrient solutions was 2.0 mg L -1 for sunflower; 1.0 mg L -1 for cotton, sorghum, wheat, and soybean; and 0.5 mg L -1 or less for field bean, rice, and maize. All crops achieved optimum growth at 2.0 mg S L -1. Critical shoot S concentration at early stages of growth was 0.8 g kg -1 in maize and soybean; 1.1 to 1.3 g kg -1 in cotton, sorghum, and rice; and 1.4 to 1.6 g kg -1 in wheat, sunflower, and field bean. Our results demonstrate that the tolerance to low external S (
  • Authors:
    • Jayanthi, C.
    • Shekinah, D. E.
    • Sankaran, N.
  • Source: Journal of Sustainable Agriculture
  • Volume: 25
  • Issue: 3
  • Year: 2005
  • Summary: In a small-scale resource-poor farm, modest increments in productivity are no longer sufficient to justify the investment of scarce resources. Integrated farming systems with multiple enterprises pave the way for realizing increased productivity, profitability and sustainability in small farms of the developing countries. A study conducted at Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, India from July 2000 to March 2002 to optimize enterprise combination, increase employment and bring about maximum bioresource utilization and residue recycling for a 1-ha farm of the dryland tract of the western zone of Tamil Nadu compared four farming system combinations: FS 2 (crop+pigeon+goat+agroforestry+farm pond), FS 3 (crop+pigeon+buffalo+agroforestry+farm pond), and FS 4 (crop+pigeon+goat+buffalo+agroforestry+farm pond) with FS 1 (sorghum only) as the reference system. The results indicated the following: crop (0.80 ha) fertilized with buffalo manure produced on the farm, with pigeon (10 pairs on 0.01 ha), goat (5:1 female:male on 0.02 ha), buffalo (2 milking buffaloes+1 calf on 0.03 ha), agroforestry (0.10 ha) and farm pond (0.04 ha) was the profitable system enterprise that generated higher employment year-round. This system also facilitated the maximum recycling of resources and residues generated on the farm among the enterprises. The output and the waste of one enterprise served as input to another. The nutritive value of the system in terms of carbohydrate, protein and fat was also highest with this enterprise combination. Thus, FS 4 seems to be the best enterprise combination as revealed by the physical indicators. However, since the purchase and maintenance of buffalo enterprise involves higher costs, for farmers who have limited cash for investment, linkage of crop (0.80 ha) with pigeon (10 pairs on 0.01 ha), goat (5:1 female:male on 0.05 ha), agroforestry (0.10 ha) and farm pond (0.04 ha) is suggested as the alternative farming system for sustainability instead of conventional cropping alone.
  • Authors:
    • Tinulele, I.
    • Prawiradilaga, D. M.
    • Koh, L. P.
    • Sodhi, N. S.
    • Putra, D. D.
    • Tan, T. H. T.
  • Source: Biological Conservation
  • Volume: 122
  • Issue: 4
  • Year: 2005
  • Summary: Unprecedented deforestation is currently underway in Southeast Asia. Since this trend is likely to continue, it is critical to determine the value of human-modified habitats (e.g., mixed-rural habitat) for conserving the regional native forest avifauna. The impacts of ongoing deforestation on the highly endemic avifauna (33%) of Sulawesi (Indonesia) are poorly understood. We sampled birds in primary and secondary forests in the Lore Lindu National Park in central Sulawesi, as well as the surrounding plantation and mixed-rural habitats. Species richness, species density and population density of forest birds showed a consistent decreasing trend in the following order: primary forests > secondary forests > mixed-rural habitat > plantations. Although primary forests contained the highest proportion (85%) of a total of 34 forest species recorded from our point count surveys, 40-yr old secondary forests and the mixed-rural habitat showed high conservation potential, containing 82% and 76% of the forest species, respectively. Plantations recorded only 32% of the forest bird species. Fifteen forest species had the highest abundance in primary forests, while two species had higher abundance outside primary forests. Our simulations revealed that all forest birds that were sensitive to native tree cover could be found in areas with at least 20% continuous native tree cover. Our study shows that although primary forests have the highest conservation value for forest avifauna, the potential of degraded habitats, such as secondary forests and the mixed-rural habitat, for conserving forest species can be enhanced with appropriate land use and management decisions. (C) 2004 Elsevier Ltd. All rights reserved.
  • Authors:
    • Chattopadhyay, N.
    • Das, H. P.
  • Source: Advances in Indian entomology: productivity and health (a silver jubilee supplement)
  • Volume: 1
  • Issue: 3
  • Year: 2005
  • Summary: Every year crops (such as rice, cotton, pigeon pea, sorghum, soyabean, groundnut, sugarcane and vegetables) are being damaged by pests and diseases. Due to lack of proper operational forecasting system for the incidences of pests and diseases, it becomes difficult to adopt efficient plant protection measures at the right time. It has been established with fair degree of accuracy that climate/weather plays major role in the incidences of pests and diseases. Thus, there is a tremendous scope of utilizing meteorological parameters for the advance information of the occurrences of the pests and diseases and ultimately scheduling of prophylactive measures can be taken scientifically and judiciously. Quite a number of studies in this regards have been made in the Agricultural Meteorology Division, India Meteorological Department (Pune, Maharashtra, India). In the present paper, a comprehensive review of the work done in this division on the impact of weather on pests and diseases of crops is presented. This information will probably help the agricultural community of the country to save the crops from the infestation of pest and disease incidences.
  • Authors:
    • Ewulo, B. S.
    • Agele, S. O.
    • Oyewusi, I. K.
  • Source: Nutrient Cycling in Agroecosystems
  • Volume: 72
  • Issue: 2
  • Year: 2005
  • Summary: The interaction of land use and seasonal microclimatic events could explain the differences in soil quality characteristics which mediate biological and physical processes of the soil under low input land use systems (plough plus harrow, strip/heap tillage, manual clearing/no till). It is hypothesised that in a humid tropical Alfisol, low input system involving reduced tillage methods, and mineral fertilizer and/or livestock manure use, would support a higher density of microbial biomass, soil aggregation, organic C and total N and hence improvement in soil quality. The dynamics of biotic and abiotic soil properties as affected by methods of seedbed preparation characterised by manural input and microclimatic transitions from wet to dry season was studied in a maize field in a tropical rain forest Alfisol in Akure, a humid rain forest zone of Nigeria. Each year, trials were carried out during the rainy (April-July) and late (September-December) seasons of 2001 and 2002. Methods of seedbed preparation involving plough plus harrow, strip/heap tillage and no tillage, and addition of different gradients of manures (mineral N and/or plant debris and live stock litter) were imposed on the soil at the site of the experiment (of comparable physical properties of bulk density and texture). Among the treatments, there were significant differences in the values of water holding capacity, aggregate stability (macro-aggregation), concentrations of microbial biomass, organic C, total and mineral N and CEC. In the rainy and late season trials, the strip/heap tillage and the no till treatments improved aggregate stability (as measured by the percent ages of aggregates between 2 and 10 mm of soil) and water holding capacity over plough+harrow. For example, in the rainy season trial, under treatments involving strip/heap tillage and the no till alone and in combination with livestock manuring and residue retention, the values of aggregates between 2 and 10 mm range from (110-116; 113-119 g/kg) and water holding capacity (0.11-0.14; 0.12-0.15 g/g) over plough+harrow (107.3 g/kg; 0.11 g/g). Similar trends were found in the values of soil microbial biomass C (377, 353; 547, 490 g/g dry soil), soil organic C (3.8, 4.3; 5.2, 5.5 g/g) and total N (2.9, 2.3; 2.9, 3.0 mg/g) for strip/heap and no till treatments compared to plough+harrow (327.6 g/g dry soil; 3.4 g/g; 2.8 mg/g). Although the %C microbial to C organic ratio (an indicator of the utilisation of organic carbon by the microbesin terms of organic matter turn over rate) was stable for all treatments, its magnitude was not constant but increased with increases in soil C concentration. The values of microbial biomass carbon to organic carbon (Cmic: Corg) ratio were higher under ploughing and heap tillage combined with mineral N (0.096, 0.099) than in no-till treatment (0.083) in the rainy season trial. Similar trends were obtained in the magnitudes of this parameter in the late season trial. Microbial biomass correlated positively with both soil organic C ( y=0.393 c-6.7; r2=0.99; P< 0.05)