344,979 research outputs found

    Cereal Leaf Beetle (Coleoptera: Chrysomelidae) Influence of Seeding Rate of Oats on Populations

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    In field and greenhouse studies, more cereal leaf beetle [Oulema melanopus (Lin- naeus)] eggs and larvae were found per unit area on spring oats, Avena sativa L., planted either at intermediate (54 kg/ha) or high (136 kg/ha) seeding rates, than when planted at a lower seeding rate (14 kg/ha). However, there were fewer eggs and larvae per stem in plantings of the high or intermediate rates than in those of the lower rate. Oats should not be planted at less than the recommended rates in beetle-infested areas

    Similar biodiversity of ectomycorrhizal fungi in set-aside plantations and ancient old-growth broadleaved forests

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    Setting aside overmature planted forests is currently seen as an option for preserving species associated with old-growth forests, such as those with dispersal limitation. Few data exist, however, on the utility of set-aside plantations for this purpose, or the value of this habitat type for biodiversity relative to old-growth semi-natural ecosystems. Here, we evaluate the contribution of forest type relative to habitat characteristics in determining species richness and composition in seven forest blocks, each containing an ancient old-growth stand (> 1000 yrs) paired with a set-aside even-aged planted stand (ca. 180 yrs). We investigated the functionally important yet relatively neglected ectomycorrhizal fungi (EMF), a group for which the importance of forest age has not been assessed in broadleaved forests. We found that forest type was not an important determinant of EMF species richness or composition, demonstrating that set-aside can be an effective option for conserving ancient EMF communities. Species richness of above-ground EMF fruiting bodies was principally related to the basal area of the stand (a correlate of canopy cover) and tree species diversity, whilst richness of below-ground ectomycorrhizae was driven only by tree diversity. Our results suggest that overmature planted forest stands, particularly those that are mixed-woods with high basal area, are an effective means to connect and expand ecological networks of ancient old-growth forests in historically deforested and fragmented landscapes for ectomycorrhizal fungi

    Evaluating the success of seed sowing in a New England grassland

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    Grassland habitat is declining in the northeastern United States, leading to a decline in associated native species. Consequently, there is considerable interest by land managers in conserving and restoring grassland habitats in the Northeast. However, unlike the Great Plains and Europe, quantitative monitoring of restoration sites is uncommon, making it difficult to improve new restoration projects. Here we evaluate a grassland restoration in Waterford, Connecticut to determine if mechanical clearing of woody vegetation combined with sowing 23 native grasses and forbs led to successful establishment of these species. We also compared cover, diversity, and colonization by exotic and woody species in planted and unplanted areas over time. In the third and fifth growing seasons after planting in 2006, we sampled the vegetation in the planted site, an unplanted zone within the planted grassland, and an adjacent unplanted grassland. Twenty of the 23 sown species established by 2010, and sown species dominated the planted area (70% of total cover). Despite the successful establishment of most sown species, species richness and diversity were no higher in the sown grassland than in adjacent unseeded areas. However, the sown grassland contained lower cover of non-native and invasive species. Big bluestem (Andropogon gerardii Vitman) established aggressively, potentially reducing both exotic colonization and native diversity. This study shows that sowing native grassland species can lead to the successful development of native-dominated grasslands. Results can inform future grassland restoration efforts in the Northeast and show that seeding with aggressive grass species may greatly impact restored plant communities

    Projecting global and regional outlooks for planted forests under the shared socio-economic pathways

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    There is rising global interest in growing more trees in order to meet growing population, climate change, and wood energy needs. Using recently published data on planted forests by country, we estimated relationships between per capita income and planted forest area that are useful for understanding prospective planted forest area futures through 2100 under various United Nations Intergovernmental Panel on Climate Change-inspired Shared Socio-economic Pathways (SSPs). Under all SSPs, projections indicate increasing global planted forest area trends for the next three to four decades and declining trends thereafter, commensurate with the quadratic functions employed. Our projections indicate somewhat less total future planted forest area than prior linear forecasts. Compared to 293 million ha (Mha) of planted forests globally in 2015, SSP5 (a vision of a wealthier world) projects the largest increase (to 334 Mha, a 14% gain) by 2055, followed by SSP2 (a continuation of historical socio-economic trends, to 327 Mha, or an 11% gain), and SSP3 (a vision of a poorer world, to 319 Mha, a 9% gain). The projected trends for major world regions differ from global trends, consistent with differing socio-economic development trajectories in those regions. Our projections based on empirical FAO data for the past 25 years, as well as those by other researchers, suggest that achieving the much more ambitious global planted forest targets proposed recently will require exceptional forest land and investment supply shifts.Peer reviewe

    Defining and Modeling Parameters Associated with Double-Planted Areas in Row Crop Production Fields

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    Automatic Section Control (ASC) utilizes current Global Positioning System (GPS) location of a planter and previously planted coverage maps to control individual planter row units, or sections of planter row units, depending on accuracy desired by equipment operators. ASC eliminates double-planting in areas of agricultural fields where planter overlap is unavoidable, such as end rows, point rows, and around internal field obstacles. Due to costs associated with purchasing ASC, farm managers are interested in rate of return on investment, which depends on several factors such as field boundary irregularity, operator response time, and crop yield response to double-planting. Georeferenced planting data was collected for 52 fields in order to create maps in ArcGIS for calculating percent minimum double-planted area and operator response time. Cotton and corn yield data were collected from test plots at the Research and Education Center at Milan, Tennessee to analyze effects of double-planting on crop yields. Average field size was 33.2 acres and average percent double-planted area was 4.55%. Twenty-two geometry factors were calculated for each field to be used as independent variables in predicting percent minimum double-planted area. Variable selection and Principal Component Analysis (PCA) where conducted to develop best fit models for predicting percent double-planted area and validated using multiple and simple linear regression. The model with the best goodness of fit retained six variables with an R2 of 0.83 (p \u3c 0.0001). Two spatial models were also developed in ArcGIS for estimating percent minimum double-planted area of a field. The simplest model only required a field boundary shapefile and could be automated using the Model Builder function in ArcGIS. Operator response time was calculated using original planting maps. Operators over-planted 58.8% of the time by an average of 8.2 feet and under-planted 41.2% of the time by an average of 9.0 feet. Tukey’s mean separation method was used to determine if cotton and corn yields differed significantly between single-planted plots and double-planted plot treatments. Significant differences were identified in cotton yields but not in corn at an alpha level of 5%

    Santa Rosa Island Restoration Study: Fog Fences vs. No Fences

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    Santa Rosa Island, Channel Islands National Park, was grazed by cattle, sheep, pigs, elk, and deer for 154 years, degrading the island’s vegetation and causing erosion. In 1998, the livestock were removed, and in 2011 the remaining big game animals were removed, allowing ecosystem recovery to begin. This study evaluated growth of two native species planted in 2016, at the cloud forest restoration site on the Soledad Ridge. Baccharis pilularis (coyote brush) was planted as nursery stock from 2-inch pots, while Quercus pacifica (island scrub oak) was planted as sprouted acorns. The plants were watered with drip irrigation 2016-2018, and some had “fog fences” of galvanized 1-inch wire covered with 40% shade cloth installed to intercept blowing fog and deposit it as fog drip along the planting line. The restoration area had three sites with different substrate types: Site 1 consisted of soil, Site 2 was bedrock, and Site 3 had bedrock covered by 1-2 cm of silt. In 2019, we inventoried species present, species height and canopy area. The purpose was to evaluate if the plants planted near a fog fence were larger in height and canopy area than those planted without a fog fence. Plants growing with fog fences were only found larger than those without when observing all the sites together for Baccharis pilularis (p=0.000 for average height; p=0.001 for average canopy area) and were not found larger when observing all the sites together for Quercus pacifica (p=0.289 for average height; p=0.083 for average canopy area). However, all three sites had different substrate types so the data was analyzed for the individual sites as well. The study shows that there are significant differences in height between plants planted with fog fences versus plants planted with no fences, but that the differences vary across different substrate types

    The social & economic implications of alternative land uses involving pastoral farming and forestry in Northland : a thesis presented in partial fulfilment of the requirements for the degree of Master of Philosophy in Natural Resource and Environmental Economics at Massey University

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    This thesis is a scenario study which examines the social and economic impacts of different types of forestry being established in an area of pastoral farmland in Northland, New Zealand. Detailed production, income, expenditure, employment and demographic data was collected from 57 of the 59 farms in the study area. This included expenditure direction data. Those businesses and schools which supported, and were in turn supported by, the study area farms were interviewed to find out the importance of these farms to their continued operation. This pastoral farming scenario is then compared with four forestry scenarios - two conventional forestry scenarios, plus a woodlot and finally an agroforestry scenario. In the first conventional forestry scenario all the study area farms (15,000 hectares) are planted in exotics and in the second about 3,000 hectares are planted. With the two farm forestry scenarios about 1,000 hectares are planted. In the first conventional forestry scenario forestry replaces pastoral farming, while in the second and the farm forestry scenarios pastoral farming and forestry are integrated. Variable results resulted from the comparison, with expenditure comparisons very sensitive to the time harvesting commences, the amount cut and the time span of the scenarios. (Thirty-five years.) These comparisons were also sensitive to the locality in which farming and forestry expenditure were being compared. Forestry expenditure would be markedly higher than farming expenditure once harvesting commenced. But farming has higher backward linkage multipliers and unless forestry processing plants are established, the conventional forestry developments in the scenarios imply a relative decline in regional incomes and employment. If forestry processing plants are established, an increase in regional incomes and employment is implied. Woodlot and agroforestry generally imply an increase in expenditure and employment without the drop in agricultural spending associated with conventional forestry activities on former pastoral farmland. Conventional forestry would result in disruption to the existing social structure. It may result in a long term population decline, but it is likely many ex-farm houses would be re-occupied. Woodlot and agroforestry would strengthen the existing social and economic structure. It is concluded that the Northland United Council's interest and concern about the afforestation of pastoral farmland is justified. However, the rural decline, the corporatisation of government departments, plus the impacts of forestry harvesting and wood processing are considered to be of more importance in the establishment of regional planning priorities

    The social & economic implications of alternative land uses involving pastoral farming and forestry in Northland : a thesis presented in partial fulfilment of the requirements for the degree of Master of Philosophy in Natural Resource and Environmental Economics at Massey University

    Get PDF
    This thesis is a scenario study which examines the social and economic impacts of different types of forestry being established in an area of pastoral farmland in Northland, New Zealand. Detailed production, income, expenditure, employment and demographic data was collected from 57 of the 59 farms in the study area. This included expenditure direction data. Those businesses and schools which supported, and were in turn supported by, the study area farms were interviewed to find out the importance of these farms to their continued operation. This pastoral farming scenario is then compared with four forestry scenarios - two conventional forestry scenarios, plus a woodlot and finally an agroforestry scenario. In the first conventional forestry scenario all the study area farms (15,000 hectares) are planted in exotics and in the second about 3,000 hectares are planted. With the two farm forestry scenarios about 1,000 hectares are planted. In the first conventional forestry scenario forestry replaces pastoral farming, while in the second and the farm forestry scenarios pastoral farming and forestry are integrated. Variable results resulted from the comparison, with expenditure comparisons very sensitive to the time harvesting commences, the amount cut and the time span of the scenarios. (Thirty-five years.) These comparisons were also sensitive to the locality in which farming and forestry expenditure were being compared. Forestry expenditure would be markedly higher than farming expenditure once harvesting commenced. But farming has higher backward linkage multipliers and unless forestry processing plants are established, the conventional forestry developments in the scenarios imply a relative decline in regional incomes and employment. If forestry processing plants are established, an increase in regional incomes and employment is implied. Woodlot and agroforestry generally imply an increase in expenditure and employment without the drop in agricultural spending associated with conventional forestry activities on former pastoral farmland. Conventional forestry would result in disruption to the existing social structure. It may result in a long term population decline, but it is likely many ex-farm houses would be re-occupied. Woodlot and agroforestry would strengthen the existing social and economic structure. It is concluded that the Northland United Council's interest and concern about the afforestation of pastoral farmland is justified. However, the rural decline, the corporatisation of government departments, plus the impacts of forestry harvesting and wood processing are considered to be of more importance in the establishment of regional planning priorities
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