17 research outputs found
Assessing Extension Education Efforts in Afghanistan through the Eyes of U.S. Agricultural Support Personnel
Assessment of agricultural extension education efforts in Afghanistan was conducted through a qualitative case study of eight U.S. support personnel serving in the country. Security & access and provincial diversity were two overriding factors which determined how the three key attributes of assessment, content and process (Barrick et al., 2009) were able to function in an Afghan agricultural extension education program. Respondents indicated training should focus on young farmers and local farm demonstration sites should be essential program components. Respondents stressed recruitment of agents from local districts when this would not imperil the agents or their families. Respondents also insisted education should be the primary role of the Afghan extension agent, and networking to facilitate an interchange of ideas among Afghan professionals should be encouraged
Seasonal weather and climate prediction over area burned in grasslands of northeast China
© 2020, The Author(s). Grassland fire dynamics are subject to myriad climatic, biological, and anthropogenic drivers, thresholds, and feedbacks and therefore do not conform to assumptions of statistical stationarity. The presence of non-stationarity in time series data leads to ambiguous results that can misinform regional-level fire management strategies. This study employs non-stationarity in time series data among multiple variables and multiple intensities using dynamic simulations of autoregressive distributed lag models to elucidate key drivers of climate and ecological change on burned grasslands in Xilingol, China. We used unit root methods to select appropriate estimation methods for further analysis. Using the model estimations, we developed scenarios emulating the effects of instantaneous changes (i.e., shocks) of some significant variables on climate and ecological change. Changes in mean monthly wind speed and maximum temperature produce complex responses on area burned, directly, and through feedback relationships. Our framework addresses interactions among multiple drivers to explain fire and ecosystem responses in grasslands, and how these may be understood and prioritized in different empirical contexts needed to formulate effective fire management policies
Facilitating Oak and Hickory Regeneration in Mature Central Hardwood Forests
Advanced oak and hickory regeneration is often absent in mature oak-hickory forests in the Central Hardwood Region of the United States. Prescribed fire and thinning, alone and combined, are commonly prescribed silvicultural treatments that are recommended to initiate the regeneration process. This study examined the regeneration response in three mature oak stands following four treatments: (1) thin, (2) burn, (3) thinning and burning, or (4) no treatment (control). Ten years after initial treatment, results indicate that oak and hickory seedlings had greater height and diameter in the thinning and burning treatment compared to the control and that this treatment may help facilitate desirable regeneration in mature oak-hickory forests
Mitigation of Climate Change for Urban Agriculture: Water Management of Culinary Herbs Grown in an Extensive Green Roof Environment
Extensive green roofs provide space for local agriculture in dense urban environments. However, already extreme drought and heat conditions on green roofs are likely to worsen under future climates, challenging urban crop production and impeding food security. The potential productivity of annual and perennial culinary herbs on an extensive green roof (~8 cm depth) with minimal, but consistent, water inputs was evaluated within a humid, subtropical climate (Southern Illinois University-Carbondale, Carbondale, IL, USA). Vigor, growth, and overwintering ability of four different perennial culinary herbs, namely garlic chives (Allium tuberosum), lavender (Lavandula angustifolia âMunstead Dwarfâ), lemon balm (Melissa officinalis), and winter thyme (Thymus vulgaris âWinter Thymeâ), as well as vigor and growth of annual âItalian large-leafâ basil (Ocimum basilicum) were evaluated under twice-weekly, weekly, and fortnightly water applications of 1 L to each plant. All species of perennial herbs produced greater dry perennial biomass and overwintering potential under the two most frequent water applications. Similarly, with weekly water applications, basil proved highly suitable for production in an extensive green roof environment. Weekly watering was required to provide commercially viable plant growth, vigor, and overwinter survival for all perennial herbs. These results indicate that supplemental water is an important consideration for sustaining culinary herb production on extensive green roofs with the increasingly hot and dry conditions provided under the climate change scenarios projected for cities currently experiencing temperate climates
Mitigation of Climate Change for Urban Agriculture: Water Management of Culinary Herbs Grown in an Extensive Green Roof Environment
Extensive green roofs provide space for local agriculture in dense urban environments. However, already extreme drought and heat conditions on green roofs are likely to worsen under future climates, challenging urban crop production and impeding food security. The potential productivity of annual and perennial culinary herbs on an extensive green roof (~8 cm depth) with minimal, but consistent, water inputs was evaluated within a humid, subtropical climate (Southern Illinois University-Carbondale, Carbondale, IL, USA). Vigor, growth, and overwintering ability of four different perennial culinary herbs, namely garlic chives (Allium tuberosum), lavender (Lavandula angustifolia ‘Munstead Dwarf’), lemon balm (Melissa officinalis), and winter thyme (Thymus vulgaris ‘Winter Thyme’), as well as vigor and growth of annual ‘Italian large-leaf’ basil (Ocimum basilicum) were evaluated under twice-weekly, weekly, and fortnightly water applications of 1 L to each plant. All species of perennial herbs produced greater dry perennial biomass and overwintering potential under the two most frequent water applications. Similarly, with weekly water applications, basil proved highly suitable for production in an extensive green roof environment. Weekly watering was required to provide commercially viable plant growth, vigor, and overwinter survival for all perennial herbs. These results indicate that supplemental water is an important consideration for sustaining culinary herb production on extensive green roofs with the increasingly hot and dry conditions provided under the climate change scenarios projected for cities currently experiencing temperate climates
Previous Land Use and Invasive Species Impacts on Long-term Afforestation Success
The conversion of agricultural lands to forests has increased worldwide over the past few decades for multiple reasons including increasing forest connectivity and wildlife habitat. However, previous land cover and competing vegetation often impede afforestation. We established 219 plots in 29 Quercus plantations on four previous land cover types (LCT): Clover, Soybeans, Woody Brush, and Herbaceous Weeds. Plantations were located in Illinois, USA and were sampled 15â18 years after planting. Sampling data for all trees (planted and volunteer) included species, diameter, and vine presence on the main bole of the tree. Free-to-grow status was recorded for all Quercus species and estimated cover of two invasive species, Elaeagnus umbellata and Lonicera japonica, was documented on each plot. There was a strong relationship between total tree density and invasive species cover across all sites. Stocking success was lower and E. umbellata cover was higher on Woody Brush sites compared to Clover and Soybean cover types. Additionally, significantly more free-to-grow Quercus saplings occurred in Clover and Soybean cover types compared to the Woody Brush sites. The results indicate that previous land cover plays a critical role in forest afforestation. Furthermore, while historically, volunteer tree species were thought to be detrimental to the development of planted species these results suggest that with the increasing prevalence of invasive species worldwide the role of volunteer species in afforestation should be reconsidered and silvicultural protocols adjusted accordingly
Regeneration and Growth following Silvicultural Treatments in a Productive Central Hardwood Forest
The lack of desirable oak (Quercus spp.) regeneration on upland sites is a problem in the Central Hardwood Region. While the reintroduction of fire, thinning, and/or harvesting has been proposed as a solution to increase oak regeneration, these treatments may have limited impact on productive sites, and the effects on the growth of residual midstory oak stems is not clear. This study examined the regeneration response and growth of residual midstory white oak (Quercus alba) stems in a mature, oak-dominated, upland forest following four treatments: (1) burn, (2) thin and burn, (3) harvest and thin and burn, and (4) no treatment (control) at Trail of Tears State Forest located in southern Illinois. Results indicated there was no significant difference in oak density among treatments for any regeneration size class. In addition, none of the treatments resulted in a radial growth release in residual midstory white oak stems. These results suggested these treatments may need to be modified to increase oak regeneration on productive sites and indicated that there may not have been enough time since treatment application, or treatments may not have been intense enough, to release midstory residual stems
Assessing regeneration strategies for sustaining intensively used Chilgoza pine-dominated community forests in Afghanistan
Income from Chilgoza pine (Pinus gerardiana) nut harvests, grazing, and the collection of firewood support forest communities within Afghanistan's Eastern Forest Complex. Persistent instability, frequent incidence of armed conflict, limited capacity of Indigenous communities, and inaccessibility to scientific expertise on forest regeneration limit options for addressing forest degradation. Representatives from forest communities in 16 districts in Khost, Paktia, and Paktika Provinces were surveyed to assess community user perceptions of Chilgoza pine regeneration status, forest protection, and acceptability of potential regeneration strategies (rotational stand harvesting, group seed tree protection, individual seed tree protection, partial cone harvesting, and integrated method). Human activity management, primarily via fine systems and forest guards, was widely reported and was regarded as important in managed forests. Respondents who reported current implementation of regeneration methods were more likely to regard natural regeneration as important and most regarding natural regeneration as very important reported the use of partial cone crop harvest as the prevailing regeneration method. Among proposed strategies, partial cone harvesting was the most frequently chosen option where regeneration was regarded as very or somewhat important. In light of the previously reported decline of forests under prevailing management practices, these results indicate a general awareness of regeneration as a forest management issue but also a significant gap among forest users in identifying the limitations of partial cone crop harvesting without additional protection for seedlings, as a potential remedy. We offer integrated rotational harvesting and grazing management strategies as a means to promote sound silviculture practices and provide a next step for community-based forest management to sustain Chilgoza pine. The context of this work in a region where tribal politics has limited outsider input allows it to serve as a model to address natural resource management issues in similar conflict-prone settings
Data on ecological associations and stand structure of chilgoza pine (Pinus gerardiana Wall. ex D. Don) in Afghanistan
Reported here are original data related to the article âIndigenous knowledge and stand characteristics of a threatened tree species in a highly insecure area: Chilgoza pine in Afghanistanâ (Shalizi et al., 2018) [1]. A dendrochronological summary of all known chilgoza pine tree growth increment cores collected in Afghanistan is presented in this data in brief article. Chilgoza pine trees and regeneration density profiles are reported for four provinces of eastern Afghanistan. In addition, images depicting chilgoza pine forest structure, stand conditions, and utilization impacts are presented
Seasonal weather and climate prediction over area burned in grasslands of northeast China
Grassland fire dynamics are subject to myriad climatic, biological, and anthropogenic drivers, thresholds, and feedbacks and therefore do not conform to assumptions of statistical stationarity. The presence of non-stationarity in time series data leads to ambiguous results that can misinform regional-level fire management strategies. This study employs non-stationarity in time series data among multiple variables and multiple intensities using dynamic simulations of autoregressive distributed lag models to elucidate key drivers of climate and ecological change on burned grasslands in Xilingol, China. We used unit root methods to select appropriate estimation methods for further analysis. Using the model estimations, we developed scenarios emulating the effects of instantaneous changes (i.e., shocks) of some significant variables on climate and ecological change. Changes in mean monthly wind speed and maximum temperature produce complex responses on area burned, directly, and through feedback relationships. Our framework addresses interactions among multiple drivers to explain fire and ecosystem responses in grasslands, and how these may be understood and prioritized in different empirical contexts needed to formulate effective fire management policies.publishedVersio