Quantifying nitrogen fixation of agroforestry shrub species by the 15N natural abundance and dilution techniques under the greenhouse condition

Non-Peer ReviewedThe land use systems of the province of Saskatchewan has agroforestry trees such as sea buckthorn (Hippophae rhamnoides L.), caragana (Caragana arborescens Lam.) and buffaloberry (Shepherdia argentea Nutt.) as important components. They have been employed within the systems to perform functions such as ameliorating soil moisture, light and temperature through wind speed reduction and trapping snow. However, their N2-fixation capability has not been determined. Therefore in a greenhouse experiment conducted at the Agriculture greenhouse at the University of Saskatchewan, Saskatoon, SK, Canada from January 2012 ̶ April 2012, the N2-fixation rates in the test species were evaluated to know their contributions to on-farm nitrogen management. After 120 days after planting, the shoot N derived from the atmosphere (%Ndfa) in the species ranged from 20-59%, 21-70% and 3-15% for caragana, sea buckthorn and buffaloberry, respectively. Also the whole plant %Ndfa in the species ranged from 18-47%, 49-54% and 38-41% for caragana, sea buckthorn and buffaloberry, respectively by both estimation methods. The contributions of the species to soil N were 73-91, 25-261 and 15-110 kg N ha-1 for caragana, sea buckthorn and buffaloberry, respectively by both methods. The amount was sufficient to meet the N requirements of most of the forage and grass species in the province which would progressively reduce the overreliance on synthetic fertilizers and minimize the risk of agrarian-derived soil and water pollution from inorganic nutrient sources

Effects of Climate Smart Agricultural practices and Planting Dates on Maize Growth and Nutrient Uptake in Semi-Arid Tanzania

The shift of growing season’s onset due to rainfall and seasonal variability are among the climate change impacts affecting agricultural productivity in semi-arid. Previous studies have also noted the seasonal variations in planting windows in semi-arid Tanzania. Because of such rainfall variability due to uncertainties of climate change, farmers face difficulties in determining the appropriate planting dates. Though, climate-smart agriculture (CSA) practices are reinforced to mitigate such climatic extremes and sustain crop production, there is limited information on the performance of CSA practices under the uncertainty of planting windows due to unpredictable rainfall on-set and patterns. This study assessed the effects of CSA practices at different planting windows on maize growth and nutrient uptakes at Mlali village of Dodoma, Tanzania. A split-plot experimental design was adopted, treatments involved CSA practices (Chololo pits, tied ridges, intercropping and Ox-cultivation – as a control) and/at planting windows (Early, Normal and Late planting). The planting windows were determined based on previous studies and Tanzania national weather forecasts. The results showed that, CSA practices had a significant (p < 0.05) effect on maize height and N nutrient uptake. Similar biomass and Mg nutrient uptake were significantly affected (p < 0.05) by both CSA practices and planting dates though Leaf Area Index (LAI) were significantly affected (p < 0.05) by planting windows. Chololo pits and tied ridges and late planting dates had the highest soil moisture, plant heights, and biomass. Ox-cultivation had a slight high N, K and Mg nutrient uptake followed with Chololo pits and tied ridges

Effects of biophysical interactions of the alley cropping system on yield and nutrition of forage crops in Saskatchewan

PresentationCompetition between trees and crops in alley cropping systems for soil moisture, light and nutrients, especially N can lead to decreased crop yield. However, there is tree-crop interactions in alley cropping the Canadian prairies are poorly understood. This study examined the effects of light and soil moisture conditions in the alleyways on yield and nutrition of forage crops. The experiment was conducted using a 9-yeald old Manitoba maple alley cropping site with oats inter-planted in the alleys at the experimental site of the Agroforestry Development Centre, Indian Head, SK. Apart from crude protein (CP) and total nitrogen (TN) in the oats plant, dry matter content (DM), and acid detergent fiber (ADF) were not affected by distance from the tree row, orientation of oats plots and their interactions. Apparently, soil moisture (SMC) influenced yield and nutrition of oats in the northern orientation since DM, TN and CP were also higher in north facing plots. Producers may integrate trees on farm to diversify production cycles without comprising forage crop production and nutrition because no significant adverse effects were noted within 6m from the tree row

Efficiency of Three-Stone Fire and Improved Cooking Stoves using on-farm and off-farm fuels in semi-arid Tanzania

In Tanzania, fuelwood availability for cooking is an increasing challenge for rural households struggling to meet this need. Here, a possible pathway for smallholder farmers to reduce their dependency on off-farm fuelwood is evaluated. We compare the cooking performance of on-farm produced fuels, like wood from Gliricidia sepium (Jacq.) Kunth ex Walp. and Cajanus cajan (L.) Millsp. (pigeon pea stalks) with the off-farm fuelwood species Mimusops obtusifolia (Lam. Sapotaceae). Fuel performance was tested using Three-Stone Fire stoves and artisan-made Improved Cooking Stoves. We conducted 75 cooking tasks, cooking a standardized pre-defined meal with two pots in five villages in Chamwino and Kongwa districts, Dodoma region. The Controlled Cooking Test design assessed four key performance indicators: (1) time until water is boiling in pot A, (2) time until food item in pot A is ready to be consumed, (3) total cooking time per meal, including food items in pots A and B, (4) total fuel consumption per meal, including food items in pots A and B. Compared to the off-farm fuel, on-farm fuels perform better across the four key performance indicators. The results show that with regard to total cooking time per meal, including food items in pots A and B and total fuel consumption per meal, including food items in pots A and B, Improved Cooking Stoves used less time and fuel than Three-Stone Fire stoves. Regarding the key performance indicators time until water is boiling in pot A and time until food item in pot A is ready to be consumed, Three-Stone Fire stoves are faster than Improved Cooking Stoves, thus suggesting that Three-Stone Fire stoves are beneficial when cooking with only one pot. In order to reduce fuel and time consumption during cooking, the results suggest switching from off-farm to on-farm fuels; however, the choice of stove will depend on the cooking task performed