canopy Archives - Resilient Landscapes (RL)

Nutritious Food Portfolios for targeting year-round food harvest and nutrient gaps – Rumuruti

Allometric equations for predicting above-ground biomass of selected woody species to estimate carbon in East African rangelands

Agroforestry technical manual. Option: Teak – Plum – Coffee – Soybeans – Forage Grass

A set of technical manual of 7 Agroforestry options implemented in Northwest Viet Nam under Agroforestry for livelihoods of smallholder farmers in Northwest Viet Nam (Phase I) and Developing and promoting market-based agroforestry and forest rehabilitation options for Northwest Viet Nam (Phase II) project. Each guideline includes (1) Introduction, (2) Design, (3) Planting techniques and fertilizing, (4) pruning and canopy formation, (5) pests and diseases prevention, (6) harvesting, (7) economic efficiency and (8) reference

Agroforestry technical manual: Option: Longan – Maize – Forage Grass

Woody species diversity and carbon stock under different land use types at Gergera watershed in eastern Tigray, Ethiopia

Woody diversity and carbon stock estimation of land use types have critical role for the successful implementation of climate change mitigation and adaptation strategies. This study investigated relationships between woody species diversity and carbon stock in different land use types. Three land use types (area exclosure, homestead agroforestry and woodlot) were selected in the Gergera watershed, Tigray, Ethiopia. A total of 45 sample plots were established using stratified random sampling, 15 plots in each land use types. Vegetation parameters such as diameter at breast height, diameter at stump height, tree height and species type were recorded. Woody species diversity and carbon stocks significantly varied among the land use types. Woody species diversity, species richness and species density were significantly higher in exclosure compared to the other land use types. Mean above-ground woody species carbon stock in woodlot (8.79 ± 7.72) was significantly higher than both in exclosure (2.29 ± 2.73) (p = 0.002) and homestead agroforestry (4.17 ± 4.18) (p = 0.022) and similarly had higher below ground woody species carbon stock than the other two systems. However, there were no significant difference among exclosure and homestead agroforestry in total carbon stock. There were a significant relationship between woody species diversity and carbon stock (R2 = − 0.349, p = 0.019) in each land use types. Land-use change can lead to changes in species diversity and significantly contribute to carbon sequestration. Although, more carbon stock was found in woodlot dominated by Eucalyptus, this would result in water competition and other fast growing trees may be preferable.

Selection for reproductive stage drought avoidance in rice using infrared thermometry

Water deficits cause major yield reductions on the world’s rainfed riceland. The most severe water deficits occur during the reproductive phase. Differences in canopy temperature among crop cultivars are known to be related to drought avoidance characters. In developing a practical field screening system for reproductive phase drought resistance in rice (Oryza sativa L.), we assessed the canopy temperature response of a range of germplasm, and related the results to other plant characters related to drought resistance. Field experiments were conducted on a silty clay loam Typic Hapludoll at the International Rice Research Institute. Planting of the test cultivars was staggered, to synchronize flowering during the water-deficit period. Canopy temperature measurements were made on 12 dates in Trial 1 and 8 dates in Trial 2. Mean canopy temperatures (Tc) increased from 28 to 37 degrees C during the stress period. Grain yield (r2 = -0.63**) and spikelet fertility (r2 = 051**) were related to midday Tc on the day of flowering. Highly significant differences were observed in canopy temperature among entries, with low coefficients of variation (2.0-2.7%). Entries with a history of outstanding vegetative stage drought screening scores consistently remained coolest under stress. Visual drought tolerance scores (r = 0.72**) and leaf rolling scores (r = 0.68**) were correlated with mean canopy temperatures under moderate water stress, but not under severe stress (r =

Predictors of tree growth in a Dipterocarp-based agroforest: a critical assessment

Growth records from three 1 ha plots of old-growth agroforest that have been monitored for 3–7 years in Sumatra are analysed. These plots of damar agroforest show typical multi-species composition. Tree species were grouped into five sets according to species ecology and average growth rate. Variables used in the multiple linear regression to predict average annual increment were crown form index, crown position (CP) index and initial girth. Crown form (CF) index is indicative both of photosynthetic capacity and of general vigour of the tree. Crown position index is indicative of the amount of light available to a tree. Results show that crown form is the most effective predictor of growth and that initial girth, and crown position only marginally increase the percentage of variance accounted for in most cases. About 40–50% of the variance is explained by using the above mentioned variables depending on the sites. The significance of these results is discussed and some methodological improvements to the monitoring techniques currently in use are suggested.

Allometric estimation of above-ground biomass and leaf area in managed Grevillea robusta agroforestry systems

Non-destructive methods for determining the biomass and leaf area of individual trees throughout their growing cycle are an essential tool in agroforestry research, but must be capable of providing reliable estimates despite the influence that management strategies such as pruning may have on tree form. In the present study, allometric methods involving measurements of the diameter of all branches provided reliable estimates of canopy leaf area and biomass for grevillea trees (Grevillea robusta A. Cunn.; Proteaceae) grown as poles, but proved unsuitable for routine measurements because of their time-consuming nature. An alternative, less laborious method based on measurements of trunk cross-sectional area immediately below the first branch of the canopy provided satisfactory allometric estimates of leaf area and canopy biomass. Trunk biomass was determined from measurements of tree height and diameter at breast height using established methodology based on the assumption that trunk volume may be calculated using a quadratic paraboloid model; biomass was determined as the product of trunk volume and the specific gravity of the wood. The theoretical basis, development and validation of allometric methods for estimating tree growth are discussed and their wider applicability to other agroforestry systems is assessed.

Remote sensing approach for spatial planning of land management interventions in West African Savannas

Forest management, agroforestry and tree planting are some of the key approaches to sustainable rural development, and climate change adaptation and mitigation in West African savannas. However, the planning of land management interventions is hindered by the lack of information at relevant spatial resolution. We examined predictive models for mapping various tree, soil and species diversity attributes with a comparison of RapidEye and Landsat imagery. The field data was collected in the vicinity of the community-managed forest in southern Burkina Faso, where the main environmental threats are agricultural expansion and fuelwood extraction. The modelling was done using Random Forest algorithm. According to our results, tree crown cover and correlated attributes, such as basal area and tree species richness, were predicted most accurately. High spatial resolution RapidEye imagery provided the best accuracy but difference to medium resolution Landsat imagery was negligible for most attributes. Burn scar masked Landsat time series performed similar to dry season single date Landsat imagery, but the former avoids image selection and mosaicking, and could be less sensitive to artifacts due to the burn scars. The presented approach provides valuable information on important tree, soil and species diversity attributes for spatial planning of land management interventions. © 2017 Elsevier Ltd

Initial effects of fertilization and canopy management on flowering and seed and oil yields of Jatropha curcas L. in Malawi

Appropriate canopy management, including planting density and pruning, and application of fertilizer may increase flowering success and seed and oil yields of Jatropha curcas L. Two field experiments were performed from 2009 to 2011 in Balaka, Malawi, to assess the effect of planting density and pruning regime and single fertilizer application (N, P, and K) on male and female flower number and seed and oil yields of J. curcas. Planting density influenced flower sex ratio and female flower number. Branch pruning treatments did not influence the flower sex ratio but reduced seed and final oil yield by 55 % in the following year. It is claimed that J. curcas can be grown on soils with low nutrient content, but this study revealed that yield was low for non-fertilized trees. We observed higher seed and oil yields at higher N application rates (up to 203±42 % seed and 204±45 % oil yield increase) compared with the non-fertilized control. The study suggests thatcurrently used heavy pruning practice is not recommended for J. curcas cultivation, although it needs further longer term investigation. Applying nitrogen fertilizer is effective in increasing yield.

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