This book is a forge guide to the students and researchers working in the field of agricultural pollution and seeking to get relevant material to understand the current trends of generation, impacts and remediation of pollutants affecting agricultural systems.The book provides the collection of most pertinent material about themes to the readers.The book is helpful in understanding the basic concepts of agricultural pollution as well as the sources of pollutants in agriculture system.The enhancement of agricultural productivity by various environmental friendly methods and their limitations is also implemented.Furthermore, the book comprises the information about impact of pollutants on growth and productivity of agricultural crops followed by various diseases and impacts of agricultural pollutants on human health as well as to other components of ecosystem.The case studies of some countries showing impacts on its population which is caused by such pollutants.The current status of generation of agricultural wastes and its best utilization by means of environmental friendly approaches is the emergence need in this book.
Agricultural Remote Sensing at the Macaulay Institute for Soil Research is examined in three parts. The first and second outline the historical development of the remote sensing facility and its present applications. Since 1975 an automated system, linking photogrammetric and remote sensing techniques, has been developed. This system now allows resource and land use/land cover mapping to be carried out from combined aerial and satellite information. A peatland resource map of Lewis and North Harris, and a land cover map of N.E. Scotland are used as specific examples. The third part deals with future developments in remote sensing techniques and information sources, and their implications for agricultural problems. Possible relationships between crop spectra and crop yields, diseases and nutrient deficiencies are highlighted. The discussion emphasises the crucial role of ground studies in establishing the value of spectral data acquired from high altitudes.
A computer simulation model of the migration of orthophosphate in soils was applied to undisturbed soil columns treated with amounts of pig slurry up to the equivalent of 1000 t of wet slurry per ha. The kinetic parameters and adsorption data necessary in filling in the model were obtained from long-term batch phosphate fixation experiments. Computer simulation predicted a somewhat greater mobility of phosphate than was found in soil columns. The causes of this discrepancy are discussed. The necessity of taking into account the mineralisation of organic phosphorus is shown. The direct contribution of organic P in pig slurry to P-mobility in the soil was found to be negligible.
Earth worms (Lumbricus terrestris) were exposed under laboratory conditions to aldrin, endrin, DDE, parathion and carbaryl in seven different concentrations ranging from 1.5 to 150 μg/g of bedding. Results showed that earthworms were able to tolerate doses of up to 14 μg/g of bedding.without significant mortalities. However, some behavioral and physical symptoms such as “withdrawal responses” and discoloration of the skin were noted in animals where non-lethal dosages were employed. Aldrin and endrin gave an LD50 of approximately 45 μg/g, DDE gave an LD50 of 46 μg/g, parathion showed an LD50 of 34 μg/g and carbaryl which gave an LD50 of 28 μg/g showed the most lethal effect of all insecticides tested.
The results of a 6-year grazing trial in open Tabor oak woodland, dominated by annual plants, were used for the determination of the dependence of productivity on climatic fluctuations. Stepwise multiple regressions between October–November, December–January and February–March rainfall and minimum December–January temperatures resulted in high correlation coefficients, explaining 76% of the variance in the unfertilized, and even 99% of the variance in the more intensively improved and fertilized, pastures. Legumes were more dependent on total rainfall but also highly responsive to N or P dressings, whereas grasses were more responsive to early rains, especially after N dressings.
Soil conservation policy and the resultant programs of soil conservation may be viewed as efforts of planned change. A major reason for the failure of conservation programs is the assumptions or criteria upon which conservation policy is based that limit the amount of flexibility for application of programs to unusual or unanticipated situations. The assumptions relate to (1) the economic rationality of men, (2) the homogeneous distribution of knowledge and information across a population of farmers, and (3) the indivualism of the farmer in his decision-making and action. These assumptions have serious implications upon a farmer's capacity to implement and maintain conservation practices.
Seedlings of two half-sib families of American sycamore were exposed to 0.05 ppm O3, 0.10 ppm NO2, and/or 0.14 ppm SO2 for 6 h/day for 28 consecutive days. The treatments were O3, NO2, SO2 (each used alone), O3 + SO2, O3 +NO2, and O3 + NO2 SO2. Significant growth suppressions were noted for both families when exposed to O3 + SO2 or O3 + SO2 + NO2. The O3 + SO2 treatment had a more significant effect than O3 alone, and adding NO2 to the O3 + SO2 treatment further suppressed height growth significantly. A 45% and 34% growth suppression was observed for the two families (16-Syc-19 and 16-Syc-23), respectively, in response to the three pollutants in combination. The height growth of both families was significantly suppressed by O3 alone in some cases. Both families exhibited significant height growth recovery 2 weeks after removal of the pollutant stress. Pollution-induced foliar injury was never evident on the seedlings.
A soil-plant-atmosphere model was used to evaluate the effects on ammonia (NH3) exchange of changing leaf NH3 compensation concentration, atmospheric NH3 concentration, and soil surface NH3 flux density. An increase in NH3 compensation concentration from 0.5 to 5.0 μg/m3 resulted in a small, constant decrease in the NH3 uptake rates by the crop canopy under all conditions simulated. Ambient concentration and soil flux density proved to be the most critical variables in influencing net vegetative-soil NH3 exchange. Variation in soil flux density determined whether the system evolved or consumed NH3. Consequently, differences between systems in soil flux density may result in NH3 transfer via the atmosphere from agricultural lands to natural lands.
Results of computer simulation concerning transport, nonlinear adsorption, and fixation of orthophosphate in soil, based on a physico-mathematical model discussed in Part I, are presented. The consequences of application of excessive amounts of phosphate and the influence on long-term effects of fixation rate, adsorption isotherm, time of application, and equilibrium concentration were investigated. The fixation rate was found to have the greatest influence on depth of penetration. In the limiting case of very high fixation rates it was shown that the analytical solutions derived in Part I can be used to predict rate of penetration.
[The data presented here represent estimates of the nitrogen content of crop production, nitrogen use efficiency (NUE) and agricultural nitrogen inputs associated with it across the contiguous United States. Net Anthropogenic Nitrogen Input (NANI) estimates and related data are also provided. Data are presented at county, sub-regional and regional scales. Here, subregions refer to multi-county areas delineated with the goal of obtaining more uniform reporting areas than individual counties. Regions refer to the USDA Farm Resource Regions. The data are reported for 6 agricultural census years, 1987, 1992, 1997, 2002, 2007 and 2012. Estimates of the variables were derived originally from USDA agricultural census data, US population census data, and other sources, using version 3.1 of the NANI calculator toolbox [1], [2], [3]].
Exposing Bel W3 tobacco plants for 12 h to 0.03 ppm ozone did not cause any visible injury. However, subsequent exposure to 0.08 and 0.1 ppm ozone caused the earlier appearance of leaf injury, greater number of injured leaves and a larger proportion of chlorotic leaf surface than in previously untreated plants. A quantitative injury index was defined, enabling statistical testing of the injury differences between the two plant groups, and the differences were found to be significant. These effects should be taken into consideration in assessing crop damage and loss induced by ambient air pollution.
