Laboratory, greenhouse and field studies were undertaken to investigate the status of Cu and Zn and to find out whether the addition of these nutrient elements in soils would increase maize grains and yield components...Laboratory, greenhouse and field studies were undertaken to investigate the status of Cu and Zn and to find out whether the addition of these nutrient elements in soils would increase maize grains and yield components and also, remediate their constraints in coastal plain sand derived soil of southeastern Nigeria, for optimization of maize (Zea mays L.) yields. Dry matter yields, plant concentrations, plant uptake, and maize grain yields were used to evaluate the effects of Cu and Zn levels. In both the greenhouse and field experiments, hydrated Cu and Zn sulphate fertilizers were applied to the soils in separate experiments at seven levels (0, 2, 4, 6, 8, 10 and 12 kg·ha-1) for Cu and Zn respectively. The recommended N, P, and K at rates of 120, 60, 30 kg·ha-1, respectively, were also used as basal application. The results showed the status of available Cu and Zn by 0.1 N HCl was found to be low in the soil. The application of Cu and Zn into the soils significantly (P < 0.05) increased maize dry matter production, concentration, uptake and grain yields. The estimated optimum rates for Cu and Zn under greenhouse environments were established at 10 kg·Cu·ha-1 and 8 kg·Zn·ha-1, respectively. Maximum uptake and grain yields in maize were also established at 10 kg·Cu·ha-1 and 8 kg·Zn·ha-1, respectively. However, maize response curve showed that for optimum grain yield, concentration for Cu was determined to be 10 mg·kg-1, while for Zn it was 8 mg·kg-1. The current study showed that though the soils have a severe Cu and Zn deficiency, which could be due to their strong sorption capacity and nutrients mining due to intensive and continuous cropping, maize production can still be increased considerably in this soil and other similar soils in the same agro-ecological zone within a coastal plain sand derived soil by applying Cu and Zn at rates of 10 kg·Cu·ha-1 and 8 kg·Zn·ha-1, respectively.展开更多
Soil chemical degradation caused by acidity is a serious constraint to food production in most parts of the Tropics. It was in the bid to proffer solution to this that the present study was conceived. Anincubation stu...Soil chemical degradation caused by acidity is a serious constraint to food production in most parts of the Tropics. It was in the bid to proffer solution to this that the present study was conceived. Anincubation study was conducted at the laboratory of Soil Science and Meteorology Department of Michael Okpara University of Agriculture Umudike. The aim was to ascertain the effect of amendments namely: Control (no amendment), Biochar, Ash, Lime, Biochar + Poultry Manure, Ash + Poultry Manure and Lime + Poultry Manure, on soil pH and exchangeable acidity of Sandstone, Shale and Alluvium. The rate of application was 1.43 g for the sole amendments and 0.72 g each for the combined amendments to give an equivalent of 2 t/ha. They were applied to 100 g of the soil and replicated three times in a Completely Randomized Design. The incubation study lasted for eighty-four days, the pH and exchangeable acidity were determined at fourteen days intervals. The result obtained revealed that all the treatments increased the soil pH and decreased the exchangeable acidity over the control. In all parent materials, applied Lime and Lime + Pm significantly (p < 0.05) gave the highest pH of 6.6, 6.9 and 7.2 for Shale, Sandstone and Alluvium respectively on the 28<sup>th</sup> day of incubation which, was the time, the maximum pH value was attained. Biochar and Biochar + Pm were considered the appropriate amendments because the pH values they gave were towards neutral, unlike that of Lime and Lime + Pm that were towards alkaline. It is recommended that field trial of this work is conducted.展开更多
The thrust of this paper is to examine the impact of drought risk on vegetation health in North Central Nigeria. The study applied remote sensing, Geographic information system (GIS) and statistical techniques as rese...The thrust of this paper is to examine the impact of drought risk on vegetation health in North Central Nigeria. The study applied remote sensing, Geographic information system (GIS) and statistical techniques as research methodologies. Monthly rainfall data which span through a period of 56 years (1960-2017) were obtained from Nigeria Meteorological Agency (NIMET) for analysis of variation and drought characterization using SPI. Consequently, drought risk maps were produced for three different periods: 2000-2005, 2005-2010 and 2010-2015. The study made use of the near real time data of Moderate Resolution Imaging Spectroradiometer (MODIS) Terra and Aqua Normalized Difference Vegetation Index (NDVI) of 16 Day L3 Global 250 m resolution from 2000 to 2016 for analysis of vegetation health. The results of the study proved the efficacy of NDVI in highlighting areas that are currently under vegetation stress, reduction and drought. The states with reduced and low vegetation cover corresponded well to those with low rainfall hence, more vulnerable to drought risk. The summary of the NDVI results showed that Niger, plateau and Nasarawa states have low vegetation cover and are more vulnerable to drought risk.展开更多
The current climate change is affecting the environment in diverse ways. Some of the effects are good and some others bad. The good side has not been given its deserved attention in Nigeria, nor has it in most parts o...The current climate change is affecting the environment in diverse ways. Some of the effects are good and some others bad. The good side has not been given its deserved attention in Nigeria, nor has it in most parts of the world. Some areas are becoming warmer and wetter, which could enhance agriculture. This paper therefore examined the rainfall and temperature trends as tools of climate change over Kano State, north-western Nigeria, which is an area well known for agriculture. Rainfall and temperature data covering a period of 43 years (1971-2013) were collected and analyzed using the moving averages, regression and correlation statistics. Results obtained showed gradual but steady increases in both temperature and rainfall. The results indicate that Kano State is warming at an average annual rate of 0.011°C and becoming wetter at a rate of 21.26 mm per annum. An implication of this increased rainfall for farmers in the area is the opportunity to increase crop and animal production. This is because more rainfall can now be harvested. Also, soil moisture, rivers, dams, and ponds are being recharged more, thus making water more available and longer lasting for crops and animals.展开更多
This study centers on applying the statistical downscaling technique to the daily minimum and maximum temperatures of Port Harcourt from the period 1985-2014. To select the period of calibration, the wilby and wigley ...This study centers on applying the statistical downscaling technique to the daily minimum and maximum temperatures of Port Harcourt from the period 1985-2014. To select the period of calibration, the wilby and wigley assumption of 2014 was adopted. However, the Bruckner circle assumption was adopted in selecting the normal under review. Secondary data of minimum and maximum temperatures for Port Harcourt were collected from the archive of Nigerian meteorological agency (NIMET). The grid cell of the HadCM3 corresponding to the Port Harcourt meteorological station was selected from the HadCM3 website to generate the largescale predictors. Data for temperature was there after normalized for the period of calibration. To analyze data, ANOVA and Paired t tests were used. Result showed that, the model was significant at p °C from 1960-2080, while for B2 the increase will be 0.18°C for same period. For minimum temperature, the ANOVA also showed a difference of 0.21°C and 0.11°C for A2 and B2 respectively. The paired t test statistics showed that these variations in temperatures for both maximum and minimum at A2 and B2 scenarios are significant at p < 0.05. Reforestation, afforestation, carbon sequestration are strongly advocated.展开更多
文摘Laboratory, greenhouse and field studies were undertaken to investigate the status of Cu and Zn and to find out whether the addition of these nutrient elements in soils would increase maize grains and yield components and also, remediate their constraints in coastal plain sand derived soil of southeastern Nigeria, for optimization of maize (Zea mays L.) yields. Dry matter yields, plant concentrations, plant uptake, and maize grain yields were used to evaluate the effects of Cu and Zn levels. In both the greenhouse and field experiments, hydrated Cu and Zn sulphate fertilizers were applied to the soils in separate experiments at seven levels (0, 2, 4, 6, 8, 10 and 12 kg·ha-1) for Cu and Zn respectively. The recommended N, P, and K at rates of 120, 60, 30 kg·ha-1, respectively, were also used as basal application. The results showed the status of available Cu and Zn by 0.1 N HCl was found to be low in the soil. The application of Cu and Zn into the soils significantly (P < 0.05) increased maize dry matter production, concentration, uptake and grain yields. The estimated optimum rates for Cu and Zn under greenhouse environments were established at 10 kg·Cu·ha-1 and 8 kg·Zn·ha-1, respectively. Maximum uptake and grain yields in maize were also established at 10 kg·Cu·ha-1 and 8 kg·Zn·ha-1, respectively. However, maize response curve showed that for optimum grain yield, concentration for Cu was determined to be 10 mg·kg-1, while for Zn it was 8 mg·kg-1. The current study showed that though the soils have a severe Cu and Zn deficiency, which could be due to their strong sorption capacity and nutrients mining due to intensive and continuous cropping, maize production can still be increased considerably in this soil and other similar soils in the same agro-ecological zone within a coastal plain sand derived soil by applying Cu and Zn at rates of 10 kg·Cu·ha-1 and 8 kg·Zn·ha-1, respectively.
文摘Soil chemical degradation caused by acidity is a serious constraint to food production in most parts of the Tropics. It was in the bid to proffer solution to this that the present study was conceived. Anincubation study was conducted at the laboratory of Soil Science and Meteorology Department of Michael Okpara University of Agriculture Umudike. The aim was to ascertain the effect of amendments namely: Control (no amendment), Biochar, Ash, Lime, Biochar + Poultry Manure, Ash + Poultry Manure and Lime + Poultry Manure, on soil pH and exchangeable acidity of Sandstone, Shale and Alluvium. The rate of application was 1.43 g for the sole amendments and 0.72 g each for the combined amendments to give an equivalent of 2 t/ha. They were applied to 100 g of the soil and replicated three times in a Completely Randomized Design. The incubation study lasted for eighty-four days, the pH and exchangeable acidity were determined at fourteen days intervals. The result obtained revealed that all the treatments increased the soil pH and decreased the exchangeable acidity over the control. In all parent materials, applied Lime and Lime + Pm significantly (p < 0.05) gave the highest pH of 6.6, 6.9 and 7.2 for Shale, Sandstone and Alluvium respectively on the 28<sup>th</sup> day of incubation which, was the time, the maximum pH value was attained. Biochar and Biochar + Pm were considered the appropriate amendments because the pH values they gave were towards neutral, unlike that of Lime and Lime + Pm that were towards alkaline. It is recommended that field trial of this work is conducted.
文摘The thrust of this paper is to examine the impact of drought risk on vegetation health in North Central Nigeria. The study applied remote sensing, Geographic information system (GIS) and statistical techniques as research methodologies. Monthly rainfall data which span through a period of 56 years (1960-2017) were obtained from Nigeria Meteorological Agency (NIMET) for analysis of variation and drought characterization using SPI. Consequently, drought risk maps were produced for three different periods: 2000-2005, 2005-2010 and 2010-2015. The study made use of the near real time data of Moderate Resolution Imaging Spectroradiometer (MODIS) Terra and Aqua Normalized Difference Vegetation Index (NDVI) of 16 Day L3 Global 250 m resolution from 2000 to 2016 for analysis of vegetation health. The results of the study proved the efficacy of NDVI in highlighting areas that are currently under vegetation stress, reduction and drought. The states with reduced and low vegetation cover corresponded well to those with low rainfall hence, more vulnerable to drought risk. The summary of the NDVI results showed that Niger, plateau and Nasarawa states have low vegetation cover and are more vulnerable to drought risk.
文摘The current climate change is affecting the environment in diverse ways. Some of the effects are good and some others bad. The good side has not been given its deserved attention in Nigeria, nor has it in most parts of the world. Some areas are becoming warmer and wetter, which could enhance agriculture. This paper therefore examined the rainfall and temperature trends as tools of climate change over Kano State, north-western Nigeria, which is an area well known for agriculture. Rainfall and temperature data covering a period of 43 years (1971-2013) were collected and analyzed using the moving averages, regression and correlation statistics. Results obtained showed gradual but steady increases in both temperature and rainfall. The results indicate that Kano State is warming at an average annual rate of 0.011°C and becoming wetter at a rate of 21.26 mm per annum. An implication of this increased rainfall for farmers in the area is the opportunity to increase crop and animal production. This is because more rainfall can now be harvested. Also, soil moisture, rivers, dams, and ponds are being recharged more, thus making water more available and longer lasting for crops and animals.
文摘This study centers on applying the statistical downscaling technique to the daily minimum and maximum temperatures of Port Harcourt from the period 1985-2014. To select the period of calibration, the wilby and wigley assumption of 2014 was adopted. However, the Bruckner circle assumption was adopted in selecting the normal under review. Secondary data of minimum and maximum temperatures for Port Harcourt were collected from the archive of Nigerian meteorological agency (NIMET). The grid cell of the HadCM3 corresponding to the Port Harcourt meteorological station was selected from the HadCM3 website to generate the largescale predictors. Data for temperature was there after normalized for the period of calibration. To analyze data, ANOVA and Paired t tests were used. Result showed that, the model was significant at p °C from 1960-2080, while for B2 the increase will be 0.18°C for same period. For minimum temperature, the ANOVA also showed a difference of 0.21°C and 0.11°C for A2 and B2 respectively. The paired t test statistics showed that these variations in temperatures for both maximum and minimum at A2 and B2 scenarios are significant at p < 0.05. Reforestation, afforestation, carbon sequestration are strongly advocated.
