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Sample records for agricultural landscape vyznam

  1. Incorporating Bioenergy in Sustainable Landscape Designs Workshop Two: Agricultural Landscapes

    SciTech Connect

    Negri, M. Cristina; Ssegane, H.

    2015-08-01

    The Bioenergy Technologies Office hosted two workshops on Incorporating Bioenergy in Sustainable Landscape Designs with Oak Ridge and Argonne National Laboratories in 2014. The second workshop focused on agricultural landscapes and took place in Argonne, IL from June 24—26, 2014. The workshop brought together experts to discuss how landscape design can contribute to the deployment and assessment of sustainable bioenergy. This report summarizes the discussions that occurred at this particular workshop.

  2. LANDSCAPE MANAGEMENT FOR RESTORATION OF AGRICULTURAL WATERSHEDS

    EPA Science Inventory

    As part of CEAP, we conducted a review of the available literature on landscape management to achieve improvement of water quality, water quantity, soil quality, and air quality in agricultural systems. At least 15 general principles emerged from this review. These principles wil...

  3. Monitoring of Agricultural Landscape in Norway

    NASA Astrophysics Data System (ADS)

    Wallin, H. G.; Engan, G.

    2012-07-01

    An overall societal aim is to ensure a sustainable use and management of agricultural landscapes. This requires continuous delivery of reliable and up-to-date information to decision-makers. To be able to deliver this information, a monitoring program for agricultural landscapes was initiated in Norway 13 years ago. The program documents and reports on land use / land cover changes from data captured through interpretation of true colour aerial photos using stereo instruments. The monitoring programme is based on a sample of 1000 squares of 1 × 1 km and the entire sample of squares is photographed over a five-year period. Each square is then mapped repeatedly every fifth year to record changes. Aerial photo interpretation is based on a custom classification system which is built up hierarchically, with three levels. The first level comprises seven land type classes: Agricultural land, Bare ground, Semi-natural open vegetation, Unforested wetland vegetation, Forest, Urban areas and Water. These land classes are further divided into 24 land types at level two, and approximately 100 land types at level 3. In addition to land type units we map both line elements like stone fences and point elements like buildings and solitary threes. By use of indicators that describe status and change focusing on themes of particular policy interest, we can report on whether policy aims are being fulfilled or not. Four indicator themes have been in focus hitherto: landscape spatial structure, biological diversity, cultural heritage and accessibility. Our data is stored in databases and most of the data quality check/structure process and analyses are now being made in open source software like PostGIS and PostSQL. To assess the accuracy of the photo-interpretation, ground truthing is carried out on 10 % of the squares. The results of this operation document the benefits of having access to photos of the same area from two different years. The program is designed first and foremost to

  4. Farming with Grass: Achieving Sustainable Mixed Agricultural Landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agriculture in grassland environments is facing multiple stresses from shifting demographics, declining and fragmented agricultural landscapes, declining environmental quality, variable and changing climate, volatile and increasing energy costs, marginal economic returns, and globalization. Grassla...

  5. Redistribution of soil and soil organic carbon on agricultural landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Patterns of soil organic carbon (SOC) vary widely across the landscape leading to large uncertainties in the SOC budgets for agricultural systems especially for landscapes where water, tillage, and wind erosion redistributes soil and SOC across the landscape. It is often assumed that soil erosion r...

  6. A Landscape Perspective on Sustainability of Agricultural Systems

    SciTech Connect

    Dale, Virginia H; Kline, Keith L; Kaffka, Stephen R; Langeveld, J.W.A.

    2013-01-01

    Landscape sustainability of agricultural systems considers effects of farm activities on social, economic, and ecosystem services at local and regional scales. Sustainable agriculture entails: defining sustainability, developing easily measured indicators of sustainability, moving toward integrated agricultural systems, and offering incentives or imposing regulations to affect farmer behavior. A landscape perspective is useful because landscape ecology provides theory and methods for dealing with spatial heterogeneity, scaling, integration, and complexity. To implement agricultural sustainability, we propose adopting a systems perspective, recognizing spatial heterogeneity, addressing the influences of context, and integrating landscape-design principles. Topics that need further attention at local and regional scales include (1) protocols for quantifying material and energy flows; (2) effects of management practices; (3) incentives for enhancing social, economic, and ecosystem services; (4) integrated landscape planning and management; (5) monitoring and assessment; (6) effects of societal demand; and (7) consistent and holistic policies for promoting agricultural sustainability.

  7. Monitoring the agricultural landscape for insect resistance

    NASA Astrophysics Data System (ADS)

    Casas, Joseph; Glaser, J. A.; Copenhaver, Ken

    Farmers in 25 countries on six continents are using plant biotechnology to solve difficult crop production challenges and conserve the environment. In fact, 13.3 million farmers, which include 90 percent of the farming in developing countries, choose to plant biotech crops. Over the past decade, farmers increased area planted in genetically modified (GM) crops by more than 10 percent each year, thus increasing their farm income by more than 44 billion US dollars (1996-2007), and achieved economic, environmental and social benefits in crops such as soybeans, canola, corn and cotton. To date, total acres of biotech crops harvested exceed more than 2 billion with a proven 13-year history of safe use. Over the next decade, expanded adoption combined with current research on 57 crops in 63 countries will broaden the advantages of genetically modified foods for growers, consumers and the environment. Genetically modified (GM) crops with the ability to produce toxins lethal to specific insect pests are covering a larger percentage of the agricultural landscape every year. The United States department of Agriculture (USDA) estimated that 63 percent of corn and 65 percent of cotton contained these specific genetic traits in 2009. The toxins could protect billions of dollars of loss from insect damage for crops valued at greater than 165 billion US dollars in 2008. The stable and efficient production of these crops has taken on even more importance in recent years with their use, not only as a food source, but now also a source of fuel. It is in the best interest of the United States Environmental Protection Agency (USEPA) to ensure the continued efficacy of toxin producing GM crops as their use reduces pesticides harmful to humans and animals. However, population genetics models have indicated the risk of insect pests developing resistance to these toxins if a high percentage of acreage is grown in these crops. The USEPA is developing methods to monitor the agricultural

  8. Natural enemy interactions constrain pest control in complex agricultural landscapes

    PubMed Central

    Martin, Emily A.; Reineking, Björn; Seo, Bumsuk; Steffan-Dewenter, Ingolf

    2013-01-01

    Biological control of pests by natural enemies is a major ecosystem service delivered to agriculture worldwide. Quantifying and predicting its effectiveness at large spatial scales is critical for increased sustainability of agricultural production. Landscape complexity is known to benefit natural enemies, but its effects on interactions between natural enemies and the consequences for crop damage and yield are unclear. Here, we show that pest control at the landscape scale is driven by differences in natural enemy interactions across landscapes, rather than by the effectiveness of individual natural enemy guilds. In a field exclusion experiment, pest control by flying insect enemies increased with landscape complexity. However, so did antagonistic interactions between flying insects and birds, which were neutral in simple landscapes and increasingly negative in complex landscapes. Negative natural enemy interactions thus constrained pest control in complex landscapes. These results show that, by altering natural enemy interactions, landscape complexity can provide ecosystem services as well as disservices. Careful handling of the tradeoffs among multiple ecosystem services, biodiversity, and societal concerns is thus crucial and depends on our ability to predict the functional consequences of landscape-scale changes in trophic interactions. PMID:23513216

  9. Natural enemy interactions constrain pest control in complex agricultural landscapes.

    PubMed

    Martin, Emily A; Reineking, Björn; Seo, Bumsuk; Steffan-Dewenter, Ingolf

    2013-04-01

    Biological control of pests by natural enemies is a major ecosystem service delivered to agriculture worldwide. Quantifying and predicting its effectiveness at large spatial scales is critical for increased sustainability of agricultural production. Landscape complexity is known to benefit natural enemies, but its effects on interactions between natural enemies and the consequences for crop damage and yield are unclear. Here, we show that pest control at the landscape scale is driven by differences in natural enemy interactions across landscapes, rather than by the effectiveness of individual natural enemy guilds. In a field exclusion experiment, pest control by flying insect enemies increased with landscape complexity. However, so did antagonistic interactions between flying insects and birds, which were neutral in simple landscapes and increasingly negative in complex landscapes. Negative natural enemy interactions thus constrained pest control in complex landscapes. These results show that, by altering natural enemy interactions, landscape complexity can provide ecosystem services as well as disservices. Careful handling of the tradeoffs among multiple ecosystem services, biodiversity, and societal concerns is thus crucial and depends on our ability to predict the functional consequences of landscape-scale changes in trophic interactions. PMID:23513216

  10. Sustainable pest regulation in agricultural landscapes: a review on landscape composition, biodiversity and natural pest control

    PubMed Central

    Bianchi, F.J.J.A; Booij, C.J.H; Tscharntke, T

    2006-01-01

    Agricultural intensification has resulted in a simplification of agricultural landscapes by the expansion of agricultural land, enlargement of field size and removal of non-crop habitat. These changes are considered to be an important cause of the rapid decline in farmland biodiversity, with the remaining biodiversity concentrated in field edges and non-crop habitats. The simplification of landscape composition and the decline of biodiversity may affect the functioning of natural pest control because non-crop habitats provide requisites for a broad spectrum of natural enemies, and the exchange of natural enemies between crop and non-crop habitats is likely to be diminished in landscapes dominated by arable cropland. In this review, we test the hypothesis that natural pest control is enhanced in complex patchy landscapes with a high proportion of non-crop habitats as compared to simple large-scale landscapes with little associated non-crop habitat. In 74% and 45% of the studies reviewed, respectively, natural enemy populations were higher and pest pressure lower in complex landscapes versus simple landscapes. Landscape-driven pest suppression may result in lower crop injury, although this has rarely been documented. Enhanced natural enemy activity was associated with herbaceous habitats in 80% of the cases (e.g. fallows, field margins), and somewhat less often with wooded habitats (71%) and landscape patchiness (70%). The similar contributions of these landscape factors suggest that all are equally important in enhancing natural enemy populations. We conclude that diversified landscapes hold most potential for the conservation of biodiversity and sustaining the pest control function. PMID:16790403

  11. Modelling pollination services across agricultural landscapes

    PubMed Central

    Lonsdorf, Eric; Kremen, Claire; Ricketts, Taylor; Winfree, Rachael; Williams, Neal; Greenleaf, Sarah

    2009-01-01

    Background and Aims Crop pollination by bees and other animals is an essential ecosystem service. Ensuring the maintenance of the service requires a full understanding of the contributions of landscape elements to pollinator populations and crop pollination. Here, the first quantitative model that predicts pollinator abundance on a landscape is described and tested. Methods Using information on pollinator nesting resources, floral resources and foraging distances, the model predicts the relative abundance of pollinators within nesting habitats. From these nesting areas, it then predicts relative abundances of pollinators on the farms requiring pollination services. Model outputs are compared with data from coffee in Costa Rica, watermelon and sunflower in California and watermelon in New Jersey–Pennsylvania (NJPA). Key Results Results from Costa Rica and California, comparing field estimates of pollinator abundance, richness or services with model estimates, are encouraging, explaining up to 80 % of variance among farms. However, the model did not predict observed pollinator abundances on NJPA, so continued model improvement and testing are necessary. The inability of the model to predict pollinator abundances in the NJPA landscape may be due to not accounting for fine-scale floral and nesting resources within the landscapes surrounding farms, rather than the logic of our model. Conclusions The importance of fine-scale resources for pollinator service delivery was supported by sensitivity analyses indicating that the model's predictions depend largely on estimates of nesting and floral resources within crops. Despite the need for more research at the finer-scale, the approach fills an important gap by providing quantitative and mechanistic model from which to evaluate policy decisions and develop land-use plans that promote pollination conservation and service delivery. PMID:19324897

  12. Comparative biodiversity along a gradient of agricultural landscapes

    NASA Astrophysics Data System (ADS)

    Burel, Françoise; Baudry, Jacques; Butet, Alain; Clergeau, Philippe; Delettre, Yannick; Le Coeur, Didier; Dubs, Florence; Morvan, Nathalie; Paillat, Gilles; Petit, Sandrine; Thenail, Claudine; Brunel, Etienne; Lefeuvre, Jean-Claude

    1998-02-01

    The aim of this study is to compare biodiversity in contrasted landscape units within a small region. In western France agricultural intensification leads to changes in landscape structure: permanent grasslands are ploughed, fields enlarged and surrounding hedgerows removed or deteriorated, brooks are straightened and cleaned. South of Mont Saint Michel Bay, four landscape units have been identified along an intensification gradient. Several taxonomic groups (small mammals, birds, insects and plants) have been used to evaluate the characteristics of biodiversity along this gradient. The hypothesis that intensification of agricultural practices lead to changes in biodiversity has been tested. Biodiversity is measured by the species richness, Shannon's diversity index, equitability and similarity indexes. Our results show that intensification of agriculture does not always lead to a decrease in species richness, but to several functional responses according to taxonomic groups, either no modification, or stability by replacement of species, or loss of species. For most of the studied taxonomic groups species richness does not vary greatly along the gradient. Depending on the landscape structure and farming systems this gradient is probably truncated and does not allow to show major changes in species richness. An alternative hypothesis is that used indexes are not sensitive enough to reveal changes in biodiversity. Nevertheless, similarity indexes reveal that sensitivity to changes varies, invertebrates being more likely to perceive the dynamics of the landscapes studied than vertebrates or plants. These points have to be taken into consideration when elaborating policies for sustainable agriculture or nature conservation.

  13. Agricultural landscape simplification does not consistently drive insecticide use.

    PubMed

    Larsen, Ashley E

    2013-09-17

    The increase in agricultural production over the past 40 y has greatly altered land-use patterns, often resulting in simplified landscapes composed of large swaths of monocultures separated by small fragments of natural lands. These simplified landscapes may be more susceptible to insect pest pressure because of the loss of natural enemies and the increased size and connectivity of crop resources, and a recent analysis from a single year (2007) suggests this increased susceptibility results in increased insecticide use. I broaden the temporal analysis of this connection between landscape simplification and insecticide use by examining cross-sectional and panel data models from multiple decades (US Department of Agriculture Census of Agriculture years 2007, 2002, 1997, 1992, 1987) for seven Midwestern states composed of over 560 counties. I find that although the proportion of county in cropland--my metric for landscape simplification--was positively correlated with insecticide use in 2007, this relationship is absent or reversed in prior census years and when all years are analyzed together. This broader temporal perspective suggests that landscape simplification has inconsistent effects on insecticide use and that multiyear studies will be key to unlocking the true drivers of variation in insecticide application. PMID:24003135

  14. Landscape context and plant community composition in grazed agricultural systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Temperate humid grazinglands are an important component of the landscape of the northeastern Unites States. Grass-based agriculture is a major contributor to the economy of this region, but little is known about the basic ecology of these grazinglands. During an eight-year survey of 28 farms across ...

  15. Optimizing carbon storage and biodiversity protection in tropical agricultural landscapes.

    PubMed

    Gilroy, James J; Woodcock, Paul; Edwards, Felicity A; Wheeler, Charlotte; Medina Uribe, Claudia A; Haugaasen, Torbjørn; Edwards, David P

    2014-07-01

    With the rapidly expanding ecological footprint of agriculture, the design of farmed landscapes will play an increasingly important role for both carbon storage and biodiversity protection. Carbon and biodiversity can be enhanced by integrating natural habitats into agricultural lands, but a key question is whether benefits are maximized by including many small features throughout the landscape ('land-sharing' agriculture) or a few large contiguous blocks alongside intensive farmland ('land-sparing' agriculture). In this study, we are the first to integrate carbon storage alongside multi-taxa biodiversity assessments to compare land-sparing and land-sharing frameworks. We do so by sampling carbon stocks and biodiversity (birds and dung beetles) in landscapes containing agriculture and forest within the Colombian Chocó-Andes, a zone of high global conservation priority. We show that woodland fragments embedded within a matrix of cattle pasture hold less carbon per unit area than contiguous primary or advanced secondary forests (>15 years). Farmland sites also support less diverse bird and dung beetle communities than contiguous forests, even when farmland retains high levels of woodland habitat cover. Landscape simulations based on these data suggest that land-sparing strategies would be more beneficial for both carbon storage and biodiversity than land-sharing strategies across a range of production levels. Biodiversity benefits of land-sparing are predicted to be similar whether spared lands protect primary or advanced secondary forests, owing to the close similarity of bird and dung beetle communities between the two forest classes. Land-sparing schemes that encourage the protection and regeneration of natural forest blocks thus provide a synergy between carbon and biodiversity conservation, and represent a promising strategy for reducing the negative impacts of agriculture on tropical ecosystems. However, further studies examining a wider range of ecosystem

  16. Agricultural landscapes dynamic at the North-West of Russia

    NASA Astrophysics Data System (ADS)

    Guzel, N.

    2012-04-01

    The process of reduction of agrolandscapes has taken place some decades in the North-Western European Russia. During 100 last years the area of agricultural lands have reduced in 1,4 times on the Karelian Isthmus. The most part of it had been abandoned after change of State border after of the Second World War. The processes of overgrowing of the former agricultural lands are studied on the landscapes base. The types of landscapes are distinguished on the based of the morphological relief symptoms, characteristics of the structure rock and the humid regime. Agricultural lands occupy landscapes such as kames, sandy, sandy-loam, clayey plains, sometimes with excess moistening, sandy fluvioglacial plains, loamy morainic plains, mesotrophic and evtrophic peat-bogs. Four stages can be revealed. I - (period to 20 years after termination of agricultural use) - grass-herb meadow with unclosed brush II - (20 - 40) - shrub layer with closed or low-closed canopy and unclosed or low closed small-leaved regrowth III - (40 - 80) - closed small-leaved forest, sometime including the coniferous trees IY - predomination of the coniferous on small-leaved trees Reestablish vegetation successions can be realised by different ways, with different rate, including various trees and ecological groups of species in different landscapes. In the different sites many traits in common are discovered during this processes. The processes taking place in soil of abandoned agricultural lands are expressed more poorly than in vegetation as soil is more "conservative" element of landscape. Now most area occupies former agricultural lands, inhering on III stage and presenting itself small-leaved forest. Over the last decade because of a change in the socio-political situation there has emerged a tendency towards an increase in the area of the cultivated land in the Karelian Isthmus including the secondary development of previously abandoned lands. However, this process is going on spontaneously; there

  17. TMDL Implementation in Agricultural Landscapes: A Communicative and Systemic Approach

    NASA Astrophysics Data System (ADS)

    Jordan, Nicholas R.; Slotterback, Carissa Schively; Cadieux, Kirsten Valentine; Mulla, David J.; Pitt, David G.; Olabisi, Laura Schmitt; Kim, Jin-Oh

    2011-07-01

    Increasingly, total maximum daily load (TMDL) limits are being defined for agricultural watersheds. Reductions in non-point source pollution are often needed to meet TMDL limits, and improvements in management of annual crops appear insufficient to achieve the necessary reductions. Increased adoption of perennial crops and other changes in agricultural land use also appear necessary, but face major barriers. We outline a novel strategy that aims to create new economic opportunities for land-owners and other stakeholders and thereby to attract their voluntary participation in land-use change needed to meet TMDLs. Our strategy has two key elements. First, focused efforts are needed to create new economic enterprises that capitalize on the productive potential of multifunctional agriculture (MFA). MFA seeks to produce a wide range of goods and ecosystem services by well-designed deployment of annual and perennial crops across agricultural landscapes and watersheds; new revenue from MFA may substantially finance land-use change needed to meet TMDLs. Second, efforts to capitalize on MFA should use a novel methodology, the Communicative/Systemic Approach (C/SA). C/SA uses an integrative GIS-based spatial modeling framework for systematically assessing tradeoffs and synergies in design and evaluation of multifunctional agricultural landscapes, closely linked to deliberation and design processes by which multiple stakeholders can collaboratively create appropriate and acceptable MFA landscape designs. We anticipate that application of C/SA will strongly accelerate TMDL implementation, by aligning the interests of multiple stakeholders whose active support is needed to change agricultural land use and thereby meet TMDL goals.

  18. TMDL implementation in agricultural landscapes: a communicative and systemic approach.

    PubMed

    Jordan, Nicholas R; Slotterback, Carissa Schively; Cadieux, Kirsten Valentine; Mulla, David J; Pitt, David G; Olabisi, Laura Schmitt; Kim, Jin-Oh

    2011-07-01

    Increasingly, total maximum daily load (TMDL) limits are being defined for agricultural watersheds. Reductions in non-point source pollution are often needed to meet TMDL limits, and improvements in management of annual crops appear insufficient to achieve the necessary reductions. Increased adoption of perennial crops and other changes in agricultural land use also appear necessary, but face major barriers. We outline a novel strategy that aims to create new economic opportunities for land-owners and other stakeholders and thereby to attract their voluntary participation in land-use change needed to meet TMDLs. Our strategy has two key elements. First, focused efforts are needed to create new economic enterprises that capitalize on the productive potential of multifunctional agriculture (MFA). MFA seeks to produce a wide range of goods and ecosystem services by well-designed deployment of annual and perennial crops across agricultural landscapes and watersheds; new revenue from MFA may substantially finance land-use change needed to meet TMDLs. Second, efforts to capitalize on MFA should use a novel methodology, the Communicative/Systemic Approach (C/SA). C/SA uses an integrative GIS-based spatial modeling framework for systematically assessing tradeoffs and synergies in design and evaluation of multifunctional agricultural landscapes, closely linked to deliberation and design processes by which multiple stakeholders can collaboratively create appropriate and acceptable MFA landscape designs. We anticipate that application of C/SA will strongly accelerate TMDL implementation, by aligning the interests of multiple stakeholders whose active support is needed to change agricultural land use and thereby meet TMDL goals. PMID:21547434

  19. Landscape evolution by soil redistribution in a Mediterranean agricultural context

    NASA Astrophysics Data System (ADS)

    Ciampalini, Rossano; Follain, Stéphane; Le Bissonnais, Yves

    2010-05-01

    Soils and landscapes are frequently subjected to rapid evolutions induced by climate changes and humans disturbances. Early, soil scientists had already sought to identify the dynamic interactions between soils and landscapes. Soil redistribution modelling is an appropriate analyse methodology widely utilized (Kirkby, 1985; Van Oost et al., 2000; Van Rompaey et al., 2001; Minasny and McBratney, 1999; Van Oost et al., 2005; Govers et al., 2006) to understand space time evolution in soil and landscape processes at short and medium term. The aims of this research is to develop a model able to simulate soil evolution as affected by soil redistribution processes (e.g. water-erosion processes and mechanical erosion) and to use pedological knowledge acquired from a field study coupled with the present research. The LandSoil model, here proposed, is an event based model, dimensioned for fine spatial [1 m] and medium [10 -100 years] temporal scales, taking into account a detailed representation of the agricultural landscape structure. It is composed of three modules for soil erosion/redistribution: rill erosion (Souchère et al., 2003); interrill erosion (Cerdan et al., 2002); and tillage erosion based on the mechanistic rules developed by Govers et al., 1994. After each rain and tillage event a new topography is evaluated as well as all the geometric landscape parameters. Specificities of the model are: i) long-term landscape analysis and topography balance after each rainfall; ii) evaluation of water erosion and soil mechanistic redistribution (tillage erosion); iii) taking in consideration of the landscape geometry, especially connectivity, as a significant information in describing the landscape and useful in modelling (Landscape structure management and landscape design); and iv) utilisation of various and different climate scenarios thanks to the event based model. Subsequently we apply this model to study the effect of different scenarios of land management and

  20. Measuring biodiversity and sustainable management in forests and agricultural landscapes

    PubMed Central

    Dudley, Nigel; Baldock, David; Nasi, Robert; Stolton, Sue

    2005-01-01

    Most of the world's biodiversity will continue to exist outside protected areas and there are also managed lands within many protected areas. In the assessment of millennium targets, there is therefore a need for indicators to measure biodiversity and suitability of habitats for biodiversity both across the whole landscape/seascape and in specific managed habitats. The two predominant land uses in many inhabited areas are forestry and agriculture and these are examined. Many national-level criteria and indicator systems already exist that attempt to assess biodiversity in forests and the impacts of forest management, but there is generally less experience in measuring these values in agricultural landscapes. Existing systems are reviewed, both for their usefulness in providing indicators and to assess the extent to which they have been applied. This preliminary gap analysis is used in the development of a set of indicators suitable for measuring progress towards the conservation of biodiversity in managed forests and agriculture. The paper concludes with a draft set of indicators for discussion, with suggestions including proportion of land under sustainable management, amount of produce from such land, area of natural or high quality semi-natural land within landscapes under sustainable management and key indicator species. PMID:15814357

  1. Mapping agricultural landscapes and characterizing adaptive capacity in Central America

    NASA Astrophysics Data System (ADS)

    Holland, M. B.; Imbach, P. A.; Bouroncle, C.; Donatti, C.; Leguia, E.; Martinez, M.; Medellin, C.; Saborio-Rodriguez, M.; Shamer, S.; Zamora, J.

    2013-12-01

    One of the key challenges in developing adaptation strategies for smallholder farmers in developing countries is that of a data-poor environment, where spatially-explicit information about where the most vulnerable smallholder communities are located is lacking. Developing countries tend to lack consistent and reliable maps on agricultural land use, and have limited information available on smallholder adaptive capacity. We developed a novel participatory and expert mapping process to overcome these barriers and develop detailed national-scale maps that allow for a characterization of unique agricultural landscapes based on profiles of adaptive capacity for smallholder agriculture in each area. This research focuses specifically on the Central American nations of Costa Rica, Guatemala, and Honduras, where our focus is on coffee and basic grains as the two main cropping systems. Here we present the methodology and results of a series of in-depth interviews and participatory mapping sessions with experts working within the broader agricultural sector in each country. We held individual interviews and mapping sessions with approximately thirty experts from each country, and used a detailed survey instrument for each mapping session to both spatially identify distinct agricultural landscapes, and to further characterize each area based on specific farm practices and social context. The survey also included a series of questions to help us assess the relative adaptive capacity of smallholder agriculture within each landscape. After all expert mapping sessions were completed in each country we convened an expert group to assist in both validating and refining the set of landscapes already defined. We developed a characterization of adaptive capacity by aggregating indicators into main assets-based criteria (e.g. land tenure, access to credit, access to technical assistance, sustainable farm practices) derived from further expert weighting of indicators through an online

  2. Complexity of human and ecosystem interactions in an agricultural landscape

    USGS Publications Warehouse

    Coupe, Richard H.; Barlow, Jeannie R.; Capel, Paul D.

    2012-01-01

    The complexity of human interaction in the commercial agricultural landscape and the resulting impacts on the ecosystem services of water quality and quantity is largely ignored by the current agricultural paradigm that maximizes crop production over other ecosystem services. Three examples at different spatial scales (local, regional, and global) are presented where human and ecosystem interactions in a commercial agricultural landscape adversely affect water quality and quantity in unintended ways in the Delta of northwestern Mississippi. In the first example, little to no regulation of groundwater use for irrigation has caused declines in groundwater levels resulting in loss of baseflow to streams and threatening future water supply. In the second example, federal policy which subsidizes corn for biofuel production has encouraged many producers to switch from cotton to corn, which requires more nutrients and water, counter to national efforts to reduce nutrient loads to the Gulf of Mexico and exacerbating groundwater level declines. The third example is the wholesale adoption of a system for weed control that relies on a single chemical, initially providing many benefits and ultimately leading to the widespread occurrence of glyphosate and its degradates in Delta streams and necessitating higher application rates of glyphosate as well as the use of other herbicides due to increasing weed resistance. Although these examples are specific to the Mississippi Delta, analogous situations exist throughout the world and point to the need for change in how we grow our food, fuel, and fiber, and manage our soil and water resources.

  3. Landscape patterns and soil organic carbon stocks in agricultural bocage landscapes

    NASA Astrophysics Data System (ADS)

    Viaud, Valérie; Lacoste, Marine; Michot, Didier; Walter, Christian

    2014-05-01

    Soil organic carbon (SOC) has a crucial impact on global carbon storage at world scale. SOC spatial variability is controlled by the landscape patterns resulting from the continuous interactions between the physical environment and the society. Natural and anthropogenic processes occurring and interplaying at the landscape scale, such as soil redistribution in the lateral and vertical dimensions by tillage and water erosion processes or spatial differentiation of land-use and land-management practices, strongly affect SOC dynamics. Inventories of SOC stocks, reflecting their spatial distribution, are thus key elements to develop relevant management strategies to improving carbon sequestration and mitigating climate change and soil degradation. This study aims to quantify SOC stocks and their spatial distribution in a 1,000-ha agricultural bocage landscape with dairy production as dominant farming system (Zone Atelier Armorique, LTER Europe, NW France). The site is characterized by high heterogeneity on short distance due to a high diversity of soils with varying waterlogging, soil parent material, topography, land-use and hedgerow density. SOC content and stocks were measured up to 105-cm depth in 200 sampling locations selected using conditioned Latin hypercube sampling. Additive sampling was designed to specifically explore SOC distribution near to hedges: 112 points were sampled at fixed distance on 14 transects perpendicular from hedges. We illustrate the heterogeneity of spatial and vertical distribution of SOC stocks at landscape scale, and quantify SOC stocks in the various landscape components. Using multivariate statistics, we discuss the variability and co-variability of existing spatial organization of cropping systems, environmental factors, and SOM stocks, over landscape. Ultimately, our results may contribute to improving regional or national digital soil mapping approaches, by considering the distribution of SOC stocks within each modeling unit and

  4. Stream Metabolism and Aquatic Vegetation in Agriculturally Dominated Landscapes

    NASA Astrophysics Data System (ADS)

    Munn, M. D.; Bales, J. D.; Waite, I.

    2013-12-01

    Forty-six streams across 7 agricultural areas of the United States were assessed using 2-station whole-stream metabolism techniques and aquatic vegetation measurements. Land use was dominated by agriculture, ranging from 0.1 to 92 percent (mean = 44 percent), with agricultural practices ranging from low intensity pasture to high intensity irrigated agriculture. Streams represented a gradient of nutrient concentrations for TN (0.07- 9.0 mg/L) and TP (0.002-1.7 mg/L). Measures of aquatic vegetation included benthic algal biomass (chlorophyll a/m2) and percent macrophyte cover. Additional data included stream and riparian habitat and basin features. Gross primary production (GPP) ranged from 0.1 to 12 g O2/ m2/ d, with highest production occurring in macrophyte-dominated streams in Idaho and Minnesota, and benthic periphyton-dominated streams in the Ozarks (Arkansas and Missouri). GPP was positively correlated with macrophyte cover (r=0.35), but not with algal biomass. Macrophyte driven systems occurred almost exclusively in open canopy systems where canopy was less than 27 percent. Nutrient concentrations in streams were not determined to be important explanatory variables for GPP; however, modeled estimates of nitrogen and phosphorous inputs to the watershed were related to benthic algal biomass and macrophyte cover in specific agricultural areas. Habitat played a key role in GPP, benthic algal biomass, and macrophyte cover, with indicators of light (for example, canopy cover or suspended sediment), often determined to be significant explanatory variables. Approximately 75 percent of sites had negative net ecosystem production indicating heterotrophic metabolism; intensive agriculture dominated many of these streams. Nutrient management strategies in agricultural landscapes require an understanding of nutrient sources, transport mechanisms, habitat condition, and ecosystem processes in order to make sound decisions on land use practices.

  5. Environment, agriculture, and settlement patterns in a marginal Polynesian landscape

    PubMed Central

    Kirch, P. V.; Hartshorn, A. S.; Chadwick, O. A.; Vitousek, P. M.; Sherrod, D. R.; Coil, J.; Holm, L.; Sharp, W. D.

    2004-01-01

    Beginning ca. A.D. 1400, Polynesian farmers established permanent settlements along the arid southern flank of Haleakala Volcano, Maui, Hawaiian Islands; peak population density (43-57 persons per km2) was achieved by A.D. 1700-1800, and it was followed by the devastating effects of European contact. This settlement, based on dryland agriculture with sweet potato as a main crop, is represented by >3,000 archaeological features investigated to date. Geological and environmental factors are the most important influence on Polynesian farming and settlement practices in an agriculturally marginal landscape. Interactions between lava flows, whose ages range from 3,000 to 226,000 years, and differences in rainfall create an environmental mosaic that constrained precontact Polynesian farming practices to a zone defined by aridity at low elevation and depleted soil nutrients at high elevation. Within this productive zone, however, large-scale agriculture was concentrated on older, tephra-blanketed lava flows; younger flows were reserved for residential sites, small ritual gardens, and agricultural temples. PMID:15210963

  6. Environment, agriculture, and settlement patterns in a marginal Polynesian landscape

    USGS Publications Warehouse

    Kirch, P.V.; Hartshorn, A.S.; Chadwick, O.A.; Vitousek, P.M.; Sherrod, D.R.; Coil, J.; Holm, L.; Sharp, W.D.

    2004-01-01

    Beginning ca. A.D. 1400, Polynesian farmers established permanent settlements along the arid southern flank of Haleakala Volcano, Maui, Hawaiian Islands; peak population density (43-57 persons per km2) was achieved by A.D. 1700-1800, and it was followed by the devastating effects of European contact. This settlement, based on dryland agriculture with sweet potato as a main crop, is represented by >3,000 archaeological features investigated to date. Geological and environmental factors are the most important influence on Polynesian farming and settlement practices in an agriculturally marginal landscape. Interactions between lava flows, whose ages range from 3,000 to 226,000 years, and differences in rainfall create an environmental mosaic that constrained precontact Polynesian farming practices to a zone defined by aridity at low elevation and depleted soil nutrients at high elevation. Within this productive zone, however, large-scale agriculture was concentrated on older, tephra-blanketed lava flows; younger flows were reserved for residential sites, small ritual gardens, and agricultural temples.

  7. The residence time of intensively managed agricultural landscapes

    NASA Astrophysics Data System (ADS)

    Bowling, Laura; Cherkauer, Keith; Chiu, Chun-mei; Rahman, Sanoar

    2015-04-01

    Much of the agricultural landscape across the Midwestern United States is intensively managed through numerous surface and subsurface drainage improvements, and the growing extraction of groundwater resources. The relatively recent glaciation of the North Central region means that the landscape is less dissected and hydrologically connected than older till areas. Low topographic gradients and underlying dense till which restricts vertical water movement, as well as kettle depressions, have led to poorly drained soils and extensive wetlands within the landscape. Large areas of this land could only be farmed once the excess water was removed through artificial surface and subsurface drainage. Conventional wisdom in the region maintains that subsurface tile drainage reduces the occurrence of peak flow events by increasing soil water storage capacity. At the watershed scale, this view does not take into account the coincident increase in surface drainage and reduction in residence time in surface depressions. This paper explores to what degree water management and irrigation has changed surface and subsurface water storage and residence time over the last century and how this has impacted flow duration throughout the Wabash River system in Indiana, USA. The effects of subsurface tile drains, wetlands and aquifer storage are explicitly represented within the Variable Infiltration Capacity (VIC) macroscale hydrology model. We maintain a focus on the entire Wabash River, a river system of historic importance that is also representative of many similar areas in the till plain region of the agricultural Midwest, which contribute to water quality and flood dynamics of the Mississippi river system. By lowering the water table, surface and subsurface drainage improvements have increased the subsurface storage capacity at the beginning of rain events, but this is overwhelmed by the decrease in surface storage capacity for intermediate to large events, decreasing the current

  8. Spatial heterogeneity in landscape structure influences dispersal and genetic structure: empirical evidence from a grasshopper in an agricultural landscape.

    PubMed

    Gauffre, Bertrand; Mallez, Sophie; Chapuis, Marie-Pierre; Leblois, Raphael; Litrico, Isabelle; Delaunay, Sabrina; Badenhausser, Isabelle

    2015-04-01

    Dispersal may be strongly influenced by landscape and habitat characteristics that could either enhance or restrict movements of organisms. Therefore, spatial heterogeneity in landscape structure could influence gene flow and the spatial structure of populations. In the past decades, agricultural intensification has led to the reduction in grassland surfaces, their fragmentation and intensification. As these changes are not homogeneously distributed in landscapes, they have resulted in spatial heterogeneity with generally less intensified hedged farmland areas remaining alongside streams and rivers. In this study, we assessed spatial pattern of abundance and population genetic structure of a flightless grasshopper species, Pezotettix giornae, based on the surveys of 363 grasslands in a 430-km² agricultural landscape of western France. Data were analysed using geostatistics and landscape genetics based on microsatellites markers and computer simulations. Results suggested that small-scale intense dispersal allows this species to survive in intensive agricultural landscapes. A complex spatial genetic structure related to landscape and habitat characteristics was also detected. Two P. giornae genetic clusters bisected by a linear hedged farmland were inferred from clustering analyses. This linear hedged farmland was characterized by high hedgerow and grassland density as well as higher grassland temporal stability that were suspected to slow down dispersal. Computer simulations demonstrated that a linear-shaped landscape feature limiting dispersal could be detected as a barrier to gene flow and generate the observed genetic pattern. This study illustrates the relevance of using computer simulations to test hypotheses in landscape genetics studies. PMID:25773398

  9. Nutrient mitigation efficiency in agricultural drainage ditches: An influence of landscape properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Drainage systems are integral parts of the agricultural landscapes and have the ability to intercept nutrient loading from runoff to surface water. This study investigated nutrient removal efficiency within replicated experimental conventional and controlled (with weirs) agricultural drainage ditche...

  10. Mimicking biochar-albedo feedback in complex Mediterranean agricultural landscapes

    NASA Astrophysics Data System (ADS)

    Bozzi, E.; Genesio, L.; Toscano, P.; Pieri, M.; Miglietta, F.

    2015-08-01

    Incorporation of charcoal produced by biomass pyrolysis (biochar) in agricultural soils is a potentially sustainable strategy for climate change mitigation. However, some side effects of large-scale biochar application need to be investigated. In particular a massive use of a low-reflecting material on large cropland areas may impact the climate via changes in surface albedo. Twelve years of MODIS-derived albedo data were analysed for three pairs of selected agricultural sites in central Italy. In each pair bright and dark coloured soil were identified, mimicking the effect of biochar application on the land surface albedo of complex agricultural landscapes. Over this period vegetation canopies never completely masked differences in background soil colour. This soil signal, expressed as an albedo difference, induced a local instantaneous radiative forcing of up to 4.7 W m-2 during periods of high solar irradiance. Biochar mitigation potential might therefore be reduced up to ˜30%. This study proves the importance of accounting for crop phenology and crop management when assessing biochar mitigation potential and provides more insights into the analysis of its environmental feedback.

  11. Port wine landscape: railroads, phylloxera, and agricultural science.

    PubMed

    Macedo, Marta

    2011-01-01

    It is easy to understand why regions that produce very fine goods such as port wine tend to conceal technological and scientific inputs and praise the uniqueness of the terroir. This paper suggests that, during the last decades of the nineteenth century, viticulture in the Douro region of Portugal was as much a product of soil, local farming traditions, and individual entrepreneurship as it was of modern state science and national politics for agricultural improvement. the unprecedented public projects of building a railroad and fighting phylloxera permanently changed the land of port wine. Moreover, those engineering practices of rationalization, simplification, and standardization that were inscribed on Douro's landscape proved essential for the Portuguese experience of modernization and nation-building. PMID:21563604

  12. Carbon storage of headwater riparian zones in an agricultural landscape

    PubMed Central

    2012-01-01

    Background In agricultural regions, streamside forests have been reduced in age and extent, or removed entirely to maximize arable cropland. Restoring and reforesting such riparian zones to mature forest, particularly along headwater streams (which constitute 90% of stream network length) would both increase carbon storage and improve water quality. Age and management-related cover/condition classes of headwater stream networks can be used to rapidly inventory carbon storage and sequestration potential if carbon storage capacity of conditions classes and their relative distribution on the landscape are known. Results Based on the distribution of riparian zone cover/condition classes in sampled headwater reaches, current and potential carbon storage was extrapolated to the remainder of the North Carolina Coastal Plain stream network. Carbon stored in headwater riparian reaches is only about 40% of its potential capacity, based on 242 MgC/ha stored in sampled mature riparian forest (forest > 50 y old). The carbon deficit along 57,700 km headwater Coastal Plain streams is equivalent to about 25TgC in 30-m-wide riparian buffer zones and 50 TgC in 60-m-wide buffer zones. Conclusions Estimating carbon storage in recognizable age-and cover-related condition classes provides a rapid way to better inventory current carbon storage, estimate storage capacity, and calculate the potential for additional storage. In light of the particular importance of buffer zones in headwater reaches in agricultural landscapes in ameliorating nutrient and sediment input to streams, encouraging the restoration of riparian zones to mature forest along headwater reaches worldwide has the potential to not only improve water quality, but also simultaneously reduce atmospheric CO2. PMID:22333213

  13. Conservation planning in agricultural landscapes: hotspots of conflict between agriculture and nature

    PubMed Central

    Shackelford, Gorm E; Steward, Peter R; German, Richard N; Sait, Steven M; Benton, Tim G

    2015-01-01

    Aim Conservation conflict takes place where food production imposes a cost on wildlife conservation and vice versa. Where does conservation impose the maximum cost on production, by opposing the intensification and expansion of farmland? Where does conservation confer the maximum benefit on wildlife, by buffering and connecting protected areas with a habitable and permeable matrix of crop and non-crop habitat? Our aim was to map the costs and benefits of conservation versus production and thus to propose a conceptual framework for systematic conservation planning in agricultural landscapes. Location World-wide. Methods To quantify these costs and benefits, we used a geographic information system to sample the cropland of the world and map the proportion of non-crop habitat surrounding the cropland, the number of threatened vertebrates with potential to live in or move through the matrix and the yield gap of the cropland. We defined the potential for different types of conservation conflict in terms of interactions between habitat and yield (potential for expansion, intensification, both or neither). We used spatial scan statistics to find ‘hotspots’ of conservation conflict. Results All of the ‘hottest’ hotspots of conservation conflict were in sub-Saharan Africa, which could have impacts on sustainable intensification in this region. Main conclusions Systematic conservation planning could and should be used to identify hotspots of conservation conflict in agricultural landscapes, at multiple scales. The debate between ‘land sharing’ (extensive agriculture that is wildlife friendly) and ‘land sparing’ (intensive agriculture that is less wildlife friendly but also less extensive) could be resolved if sharing and sparing were used as different types of tool for resolving different types of conservation conflict (buffering and connecting protected areas by maintaining matrix quality, in different types of matrix). Therefore, both sharing and sparing

  14. Multi-temporal analysis of an agricultural landscape transformation and abandonment (Lubietová, Central Slovakia)

    NASA Astrophysics Data System (ADS)

    Masný, Matej; Zaušková, Lubica

    2015-12-01

    Socio-political changes in the countries of Eastern and Central Europe in the era of socialism had significant effects on agricultural landscape. Collectivisation (1950 - 1970) lost almost all of traditional agricultural landscapes. On the other hand, the phenomenon of agricultural abandonment started to be significant after 1989. In the model area (part of The Polana Biosphere Reserve) these two processes that formed the agricultural landscape structure were analysed. The analyses were carried out using orthophotos that represented the landscape structure in 1949, 1986 and 2006. It was found that almost complete extinction of the traditional agricultural landscape represented by a mosaic of narrow fields and permanent grasslands occurred during the period. At the same time, increasing trend of abandonment processes was observed. In 2006, non-forestwoody vegetation covered 48% of agricultural land.Natural reforestation as the final stage of agricultural abandonment extended to 46% on the former agricultural land in 2006. Abandonment processes were the most significant already in the period of socialist agriculture. To describe the changes, landscape metrics such as Number of patches (NP), Mean patch size (MPS), Patch size standard deviation (PSSD) and Mean shape index (MSI) were used.

  15. The Impact of Landscape Complexity on Invertebrate Diversity in Edges and Fields in an Agricultural Area

    PubMed Central

    Evans, Tracy R.; Mahoney, Meredith J.; Cashatt, Everett D.; Noordijk, Jinze; de Snoo, Geert; Musters, C. J. M.

    2016-01-01

    Invertebrate diversity is important for a multitude of ecosystem services and as a component of the larger ecological food web. A better understanding of the factors influencing invertebrate taxonomic richness and diversity at both local and landscape scales is important for conserving biodiversity within the agricultural landscape. The aim of this study was to determine if invertebrate richness and diversity in agricultural field interiors and edges in central Illinois, USA, were related to the complexity of the surrounding landscape. Our results show taxonomic richness and diversity in field edges is positively related to large scale landscape complexity, but the relationship is negative for field interiors. These unexpected results need further study. PMID:26848691

  16. The Impact of Landscape Complexity on Invertebrate Diversity in Edges and Fields in an Agricultural Area.

    PubMed

    Evans, Tracy R; Mahoney, Meredith J; Cashatt, Everett D; Noordijk, Jinze; de Snoo, Geert; Musters, C J M

    2016-01-01

    Invertebrate diversity is important for a multitude of ecosystem services and as a component of the larger ecological food web. A better understanding of the factors influencing invertebrate taxonomic richness and diversity at both local and landscape scales is important for conserving biodiversity within the agricultural landscape. The aim of this study was to determine if invertebrate richness and diversity in agricultural field interiors and edges in central Illinois, USA, were related to the complexity of the surrounding landscape. Our results show taxonomic richness and diversity in field edges is positively related to large scale landscape complexity, but the relationship is negative for field interiors. These unexpected results need further study. PMID:26848691

  17. Predicting biodiversity change and averting collapse in agricultural landscapes.

    PubMed

    Mendenhall, Chase D; Karp, Daniel S; Meyer, Christoph F J; Hadly, Elizabeth A; Daily, Gretchen C

    2014-05-01

    The equilibrium theory of island biogeography is the basis for estimating extinction rates and a pillar of conservation science. The default strategy for conserving biodiversity is the designation of nature reserves, treated as islands in an inhospitable sea of human activity. Despite the profound influence of islands on conservation theory and practice, their mainland analogues, forest fragments in human-dominated landscapes, consistently defy expected biodiversity patterns based on island biogeography theory. Countryside biogeography is an alternative framework, which recognizes that the fate of the world's wildlife will be decided largely by the hospitality of agricultural or countryside ecosystems. Here we directly test these biogeographic theories by comparing a Neotropical countryside ecosystem with a nearby island ecosystem, and show that each supports similar bat biodiversity in fundamentally different ways. The island ecosystem conforms to island biogeographic predictions of bat species loss, in which the water matrix is not habitat. In contrast, the countryside ecosystem has high species richness and evenness across forest reserves and smaller forest fragments. Relative to forest reserves and fragments, deforested countryside habitat supports a less species-rich, yet equally even, bat assemblage. Moreover, the bat assemblage associated with deforested habitat is compositionally novel because of predictable changes in abundances by many species using human-made habitat. Finally, we perform a global meta-analysis of bat biogeographic studies, spanning more than 700 species. It generalizes our findings, showing that separate biogeographic theories for countryside and island ecosystems are necessary. A theory of countryside biogeography is essential to conservation strategy in the agricultural ecosystems that comprise roughly half of the global land surface and are likely to increase even further. PMID:24739971

  18. Reducing sedimentation of depressional wetlands in agricultural landscapes

    USGS Publications Warehouse

    Skagen, S.K.; Melcher, C.P.; Haukos, D.A.

    2008-01-01

    Depressional wetlands in agricultural landscapes are easily degraded by sediments and contaminants accumulated from their watersheds. Several best management practices can reduce transport of sediments into wetlands, including the establishment of vegetative buffers. We summarize the sources, transport dynamics, and effect of sediments, nutrients, and contaminants that threaten wetlands and the current knowledge of design and usefulness of grass buffers for protecting isolated wetlands. Buffer effectiveness is dependent on several factors, including vegetation structure, buffer width, attributes of the surrounding watershed (i.e., area, vegetative cover, slope and topography, soil type and structure, soil moisture, amount of herbicides and pesticides applied), and intensity and duration of rain events. To reduce dissolved contaminants from runoff, the water must infiltrate the soil where microbes or other processes can break down or sequester contaminants. But increasing infiltration also diminishes total water volume entering a wetland, which presents threats to wetland hydrology in semi-arid regions. Buffer effectiveness may be enhanced significantly by implementing other best management practices (e.g., conservation tillage, balancing input with nutrient requirements for livestock and crops, precision application of chemicals) in the surrounding watershed to diminish soil erosion and associated contaminant runoff. Buffers require regular maintenance to remove sediment build-up and replace damaged or over-mature vegetation. Further research is needed to establish guidelines for effective buffer width and structure, and such efforts should entail a coordinated, regional, multi-scale, multidisciplinary approach to evaluate buffer effectiveness and impacts. Direct measures in "real-world" systems and field validations of buffer-effectiveness models are crucial next steps in evaluating how grass buffers will impact the abiotic and biotic variables attributes that

  19. Geomorphic Controls of Soil and Carbon Redistribution Across an Agricultural Landscape

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Patterns of soil organic carbon (SOC) vary widely across the landscape leading to large uncertainties in the SOC budget especially for agricultural landscapes where water, tillage, and wind erosion redistributes soil and SOC. It is often assumed that soil erosion results in a loss of SOC from the a...

  20. From Forest Landscape to Agricultural Landscape in the Developing Tropical Country of Malaysia: Pattern, Process, and Their Significance on Policy

    NASA Astrophysics Data System (ADS)

    Abdullah, Saiful Arif; Hezri, Adnan A.

    2008-11-01

    Agricultural expansion and deforestation are spatial processes of land transformation that impact on landscape pattern. In peninsular Malaysia, the conversion of forested areas into two major cash crops—rubber and oil palm plantations—has been identified as driving significant environmental change. To date, there has been insufficient literature studying the link between changes in landscape patterns and land-related development policies. Therefore, this paper examines: (i) the links between development policies and changes in land use/land cover and landscape pattern and (ii) the significance and implications of these links for future development policies. The objective is to generate insights on the changing process of land use/land cover and landscape pattern as a functional response to development policies and their consequences for environmental conditions. Over the last century, the development of cash crops has changed the country from one dominated by natural landscapes to one dominated by agricultural landscapes. But the last decade of the century saw urbanization beginning to impact significantly. This process aligned with the establishment of various development policies, from land development for agriculture between the mid 1950s and the 1970s to an emphasis on manufacturing from the 1980s onward. Based on a case study in Selangor, peninsular Malaysia, a model of landscape pattern change is presented. It contains three stages according to the relative importance of rubber (first stage: 1900-1950s), oil palm (second stage: 1960s-1970s), and urban (third stage: 1980s-1990s) development that influenced landscape fragmentation and heterogeneity. The environmental consequences of this change have been depicted through loss of biodiversity, geohazard incidences, and the spread of vector-borne diseases. The spatial ecological information can be useful to development policy formulation, allowing diagnosis of the country’s “health” and sustainability

  1. From forest landscape to agricultural landscape in the developing tropical country of Malaysia: pattern, process, and their significance on policy.

    PubMed

    Abdullah, Saiful Arif; Hezri, Adnan A

    2008-11-01

    Agricultural expansion and deforestation are spatial processes of land transformation that impact on landscape pattern. In peninsular Malaysia, the conversion of forested areas into two major cash crops--rubber and oil palm plantations--has been identified as driving significant environmental change. To date, there has been insufficient literature studying the link between changes in landscape patterns and land-related development policies. Therefore, this paper examines: (i) the links between development policies and changes in land use/land cover and landscape pattern and (ii) the significance and implications of these links for future development policies. The objective is to generate insights on the changing process of land use/land cover and landscape pattern as a functional response to development policies and their consequences for environmental conditions. Over the last century, the development of cash crops has changed the country from one dominated by natural landscapes to one dominated by agricultural landscapes. But the last decade of the century saw urbanization beginning to impact significantly. This process aligned with the establishment of various development policies, from land development for agriculture between the mid 1950s and the 1970s to an emphasis on manufacturing from the 1980s onward. Based on a case study in Selangor, peninsular Malaysia, a model of landscape pattern change is presented. It contains three stages according to the relative importance of rubber (first stage: 1900--1950s), oil palm (second stage: 1960s--1970s), and urban (third stage: 1980s--1990s) development that influenced landscape fragmentation and heterogeneity. The environmental consequences of this change have been depicted through loss of biodiversity, geohazard incidences, and the spread of vector-borne diseases. The spatial ecological information can be useful to development policy formulation, allowing diagnosis of the country's "health" and sustainability. The

  2. Foreword to farming with grass: Achieving sustainable mixed agricultural landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Farming with Grass conference was developed to bring together diverse stakeholders in grassland environments to (a) help assess the current condition of agriculture, (b) consider alternative production scenarios for grassland agricultural ecosystems, (c) identify key issues hindering the develop...

  3. Bringing together science and policy to protect and enhance wetland ecosystem services in agricultural landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wetland ecosystems operate at the cusp of hydrological and ecological functioning of agricultural landscapes, and provide a range important functions that benefit human societies worldwide. However, agricultural development has led to the drainage, degradation, and loss of vast areas of wetland that...

  4. Biodiversity conservation and agricultural sustainability: towards a new paradigm of 'ecoagriculture' landscapes.

    PubMed

    Scherr, Sara J; McNeely, Jeffrey A

    2008-02-12

    The dominant late twentieth century model of land use segregated agricultural production from areas managed for biodiversity conservation. This module is no longer adequate in much of the world. The Millennium Ecosystem Assessment confirmed that agriculture has dramatically increased its ecological footprint. Rural communities depend on key components of biodiversity and ecosystem services that are found in non-domestic habitats. Fortunately, agricultural landscapes can be designed and managed to host wild biodiversity of many types, with neutral or even positive effects on agricultural production and livelihoods. Innovative practitioners, scientists and indigenous land managers are adapting, designing and managing diverse types of 'ecoagriculture' landscapes to generate positive co-benefits for production, biodiversity and local people. We assess the potentials and limitations for successful conservation of biodiversity in productive agricultural landscapes, the feasibility of making such approaches financially viable, and the organizational, governance and policy frameworks needed to enable ecoagriculture planning and implementation at a globally significant scale. We conclude that effectively conserving wild biodiversity in agricultural landscapes will require increased research, policy coordination and strategic support to agricultural communities and conservationists. PMID:17652072

  5. Restoration of degraded agricultural terraces: rebuilding landscape structure and process.

    PubMed

    LaFevor, M C

    2014-06-01

    The restoration of severely degraded cropland to productive agricultural capacity increases food supply, improves soil and water conservation, and enhances environmental and ecological services. This article examines the key roles that long-term maintenance plays in the processes of repairing degraded agricultural land. Field measurements from Tlaxcala, Mexico stress that restoring agricultural structures (the arrangements of landforms and vegetation) is alone insufficient. Instead, an effective monitoring and maintenance regime of agricultural structures is also crucial if the efforts are to be successful. Consequently, methods of wildland restoration and agricultural restoration may differ in the degree to which the latter must plan for and facilitate a sustained human involvement. An improved understanding of these distinctions is critical for environmental management as restoration programs that employ the technologies of intensive agriculture continue to grow in number and scope. PMID:24355068

  6. Landscape Context and Plant Community Composition in Grazed Agricultural Systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Temperate humid grazinglands are an important component of the landscape of the northeastern United States, as well as of the economy of this region, yet unlike their European counterparts, little is known about their basic ecology. During an eight-year survey of 28 farms across the northeastern Uni...

  7. BATS AND BT INSECT RESISTANCE ON AGRICULTURAL LANDSCAPES

    EPA Science Inventory

    A landscape model that utilizes land cover classification data, insect life history, insect movement, and bat foraging pressure is developed that addresses the implementation of genetically modified crops in the Winter Garden region of Texas. The principal strategy for delaying r...

  8. RIPARIAN AREAS OF AN AGRICULTURAL LANDSCAPE IN WESTERN OREGON

    EPA Science Inventory

    The Willamette Valley is a productive, diversified agricultural area in western Oregon. Pastureland and grass seed fields, mostly located on poorly drained soils, account for 60% of the agricultural land in the valley. The size and character of Willamette Valley streams and ass...

  9. Mass-flowering crops dilute pollinator abundance in agricultural landscapes across Europe.

    PubMed

    Holzschuh, Andrea; Dainese, Matteo; González-Varo, Juan P; Mudri-Stojnić, Sonja; Riedinger, Verena; Rundlöf, Maj; Scheper, Jeroen; Wickens, Jennifer B; Wickens, Victoria J; Bommarco, Riccardo; Kleijn, David; Potts, Simon G; Roberts, Stuart P M; Smith, Henrik G; Vilà, Montserrat; Vujić, Ante; Steffan-Dewenter, Ingolf

    2016-10-01

    Mass-flowering crops (MFCs) are increasingly cultivated and might influence pollinator communities in MFC fields and nearby semi-natural habitats (SNHs). Across six European regions and 2 years, we assessed how landscape-scale cover of MFCs affected pollinator densities in 408 MFC fields and adjacent SNHs. In MFC fields, densities of bumblebees, solitary bees, managed honeybees and hoverflies were negatively related to the cover of MFCs in the landscape. In SNHs, densities of bumblebees declined with increasing cover of MFCs but densities of honeybees increased. The densities of all pollinators were generally unrelated to the cover of SNHs in the landscape. Although MFC fields apparently attracted pollinators from SNHs, in landscapes with large areas of MFCs they became diluted. The resulting lower densities might negatively affect yields of pollinator-dependent crops and the reproductive success of wild plants. An expansion of MFCs needs to be accompanied by pollinator-supporting practices in agricultural landscapes. PMID:27531385

  10. Hydrologic controls on phosphorus and nitrogen biogeochemistry in agricultural landscapes

    NASA Astrophysics Data System (ADS)

    Walter, T.; McPhillips, L. E.; Archibald, J. A.; Anderson, T.; Morris, C. K.

    2012-12-01

    Nonpoint source pollution of nitrogen (N) and phosphorus (P) is a persistent threat to water resources and aquatic ecosystems. Because they have very different transport properties and, therefore, follow different pathways from the landscape to streams, it has been difficult to develop management strategies that simultaneously control both nutrients. Using a combination of modeling and empiricism, we have evidence that targeting nonpoint source control efforts to the parts of the landscape most prone to saturated (or at least wet) soil conditions has good potential for helping mitigate N and P loads to streams in the Northeastern US. With respect to P, the wet-prone soils represent the parts of the landscape most likely to generate runoff and transport P to streams. So, we have developed a variety of schemes for helping farmers avoid contaminating these areas with P. With respect to N, these areas are denitrification hotspots, so managing these areas in ways that promote carbon accumulation, either naturally or engineered, can maximize their functionality for removing nitrate from water as it flows to streams. We will present our modeling strategies for simulating soil moisture patterns across watersheds, show how we couple hydrological modeling with nutrient transport and biogeochemistry, and summarize strategies and tools we are developing to use our insights into these ecosystem functions to protect water quality.

  11. Durable strategies to deploy plant resistance in agricultural landscapes.

    PubMed

    Fabre, Frédéric; Rousseau, Elsa; Mailleret, Ludovic; Moury, Benoit

    2012-03-01

    The deployment of resistant crops often leads to the emergence of resistance-breaking pathogens that suppress the yield benefit provided by the resistance. Here, we theoretically explored how farmers' main leverages (resistant cultivar choice, resistance deployment strategy, landscape planning and cultural practices) can be best combined to achieve resistance durability while minimizing yield losses as a result of plant viruses. Assuming a gene-for-gene type of interaction, virus epidemics are modelled in a landscape composed of a mosaic of resistant and susceptible fields, subjected to seasonality, and a reservoir hosting viruses year-round. The model links the genetic and the epidemiological processes, shaping at nested scales the demogenetic dynamics of viruses. The choice of the resistance gene (characterized by the equilibrium frequency of the resistance-breaking virus at mutation-selection balance in a susceptible plant) is the most influential leverage of action. Our results showed that optimal strategies of resistance deployment range from 'mixture' (where susceptible and resistant cultivars coexist) to 'pure' strategies (with only resistant cultivar) depending on the resistance characteristics and the epidemiological context (epidemic incidence and landscape connectivity). We demonstrate and discuss gaps concerning virus epidemiology across the agro-ecological interface that must be filled to achieve sustainable disease management. PMID:22260272

  12. The Importance of Landscape Elements for Bat Activity and Species Richness in Agricultural Areas.

    PubMed

    Heim, Olga; Treitler, Julia T; Tschapka, Marco; Knörnschild, Mirjam; Jung, Kirsten

    2015-01-01

    Landscape heterogeneity is regarded as a key factor for maintaining biodiversity and ecosystem function in production landscapes. We investigated whether grassland sites at close vicinity to forested areas are more frequently used by bats. Considering that bats are important consumers of herbivorous insects, including agricultural pest, this is important for sustainable land management. Bat activity and species richness were assessed using repeated monitoring from May to September in 2010 with acoustic monitoring surveys on 50 grassland sites in the Biosphere Reserve Schorfheide-Chorin (North-East Germany). Using spatial analysis (GIS), we measured the closest distance of each grassland site to potentially connecting landscape elements (e.g., trees, linear vegetation, groves, running and standing water). In addition, we assessed the distance to and the percent land cover of forest remnants and urban areas in a 200 m buffer around the recording sites to address differences in the local landscape setting. Species richness and bat activity increased significantly with higher forest land cover in the 200 m buffer and at smaller distance to forested areas. Moreover, species richness increased in proximity to tree groves. Larger amount of forest land cover and smaller distance to forest also resulted in a higher activity of bats on grassland sites in the beginning of the year during May, June and July. Landscape elements near grassland sites also influenced species composition of bats and species richness of functional groups (open, edge and narrow space foragers). Our results highlight the importance of forested areas, and suggest that agricultural grasslands that are closer to forest remnants might be better buffered against outbreaks of agricultural pest insects due to higher species richness and higher bat activity. Furthermore, our data reveals that even for highly mobile species such as bats, a very dense network of connecting elements within the landscape is

  13. The Importance of Landscape Elements for Bat Activity and Species Richness in Agricultural Areas

    PubMed Central

    Heim, Olga; Treitler, Julia T.; Tschapka, Marco; Knörnschild, Mirjam; Jung, Kirsten

    2015-01-01

    Landscape heterogeneity is regarded as a key factor for maintaining biodiversity and ecosystem function in production landscapes. We investigated whether grassland sites at close vicinity to forested areas are more frequently used by bats. Considering that bats are important consumers of herbivorous insects, including agricultural pest, this is important for sustainable land management. Bat activity and species richness were assessed using repeated monitoring from May to September in 2010 with acoustic monitoring surveys on 50 grassland sites in the Biosphere Reserve Schorfheide-Chorin (North-East Germany). Using spatial analysis (GIS), we measured the closest distance of each grassland site to potentially connecting landscape elements (e.g., trees, linear vegetation, groves, running and standing water). In addition, we assessed the distance to and the percent land cover of forest remnants and urban areas in a 200 m buffer around the recording sites to address differences in the local landscape setting. Species richness and bat activity increased significantly with higher forest land cover in the 200 m buffer and at smaller distance to forested areas. Moreover, species richness increased in proximity to tree groves. Larger amount of forest land cover and smaller distance to forest also resulted in a higher activity of bats on grassland sites in the beginning of the year during May, June and July. Landscape elements near grassland sites also influenced species composition of bats and species richness of functional groups (open, edge and narrow space foragers). Our results highlight the importance of forested areas, and suggest that agricultural grasslands that are closer to forest remnants might be better buffered against outbreaks of agricultural pest insects due to higher species richness and higher bat activity. Furthermore, our data reveals that even for highly mobile species such as bats, a very dense network of connecting elements within the landscape is

  14. Relationships between Rural Inhabitants and Their Landscapes in Areas of Intensive Agricultural Use: A Case Study in Quebec (Canada)

    ERIC Educational Resources Information Center

    Ruiz, Julie; Domon, Gerald

    2012-01-01

    An understanding of the relationships between local populations and the landscape is crucial for reintroducing the multifunctional character of landscapes in areas of intensive agricultural use. This study proposes to identify and compare the relationships that local populations, both farmers and non-farmers, maintain with their landscapes in…

  15. Ditch network sustains functional connectivity and influences patterns of gene flow in an intensive agricultural landscape.

    PubMed

    Favre-Bac, L; Mony, C; Ernoult, A; Burel, F; Arnaud, J-F

    2016-02-01

    In intensive agricultural landscapes, plant species previously relying on semi-natural habitats may persist as metapopulations within landscape linear elements. Maintenance of populations' connectivity through pollen and seed dispersal is a key factor in species persistence in the face of substantial habitat loss. The goals of this study were to investigate the potential corridor role of ditches and to identify the landscape components that significantly impact patterns of gene flow among remnant populations. Using microsatellite loci, we explored the spatial genetic structure of two hydrochorous wetland plants exhibiting contrasting local abundance and different habitat requirements: the rare and regionally protected Oenanthe aquatica and the more commonly distributed Lycopus europaeus, in an 83 km(2) agricultural lowland located in northern France. Both species exhibited a significant spatial genetic structure, along with substantial levels of genetic differentiation, especially for L. europaeus, which also expressed high levels of inbreeding. Isolation-by-distance analysis revealed enhanced gene flow along ditches, indicating their key role in effective seed and pollen dispersal. Our data also suggested that the configuration of the ditch network and the landscape elements significantly affected population genetic structure, with (i) species-specific scale effects on the genetic neighborhood and (ii) detrimental impact of human ditch management on genetic diversity, especially for O. aquatica. Altogether, these findings highlighted the key role of ditches in the maintenance of plant biodiversity in intensive agricultural landscapes with few remnant wetland habitats. PMID:26486611

  16. Sustainable corn stover harvest strategies for Midwest agricultural landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To support emerging U.S. cellulosic bioenergy industries, 239 site-years of data from field studies at 36 sites in seven states were recently summarized in BioEnergy Research by the ARS Resilient Economic Agricultural Practices (REAP) team [formerly the Renewable Energy Assessment Project (REAP) tea...

  17. Application of the precision agricultural landscape modeling system in semiarid environments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Precision Agricultural Landscape Modeling System (PALMS) is a terrain and weather driven, distributed parameter hydrological-biophysical model primarily used in the Midwestern United States. Recently, research was started to evaluate the effectiveness of PALMS on irrigated and on dryland croppin...

  18. A survey of insect assemblages responding to volatiles from a ubiquitous fungus in an agricultural landscape

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We report here a first survey of insect orientation to fungal cultures and and fungal volatiles from a community ecology perspective. We tested whether volatiles from a ubiquitous yeast-like fungus (Aureobasidium pullulans) are broadly attractive to insects in an agricultural landscape. We evaluated...

  19. Increased area of a highly suitable host crop increases herbivore pressure in intensified agricultural landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    tLandscape simplification associated with agricultural intensification has important effects on economi-cally important arthropods. The declining cover of natural and semi-natural habitats, in particular, hasbeen shown to reduce natural-enemy attack of crop pests, but also in some cases reduced crop...

  20. Simulating semiarid dryland cropping systems using the precision agricultural landscape modeling system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Precision Agricultural Landscape Modeling System (PALMS) is a terrain and weather driven, and distributed parameter hydrological-biophysical model primarily used in the Midwestern United States. Recently, research was started to evaluate the effectiveness of PALMS on irrigated and on dryland cro...

  1. Preliminary GIS analysis of the agricultural landscape of Cuyo Cuyo, Department of Puno, Peru

    NASA Technical Reports Server (NTRS)

    Winterhalder, Bruce; Evans, Tom

    1991-01-01

    Computerized analysis of a geographic database (GIS) for Cuyo Cuyo, (Dept. Puno, Peru) is used to correlate the agricultural production zones of two adjacent communities to altitude, slope, aspect, and other geomorphological features of the high-altitude eastern escarpment landscape. The techniques exemplified will allow ecological anthropologists to analyze spatial patterns at regional scales with much greater control over the data.

  2. Nectar production in oilseeds: Food for pollinators in an agricultural landscape

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pollinating insects are in decline throughout the world, driven by a combination of factors including the loss of forage resources. The corn- and soybean-dominated agriculture of the Central and Midwestern US produces a landscape relatively devoid of nectar and pollen resources. Introducing specialt...

  3. Mineralization of soil organic matter in biochar amended agricultural landscape

    NASA Astrophysics Data System (ADS)

    Chintala, R.; Clay, D. E.; Schumacher, T. E.; Kumar, S.; Malo, D. D.

    2015-12-01

    Pyrogenic biochar materials have been identified as a promising soil amendment to enhance climate resilience, increase soil carbon recalcitrance and achieve sustainable crop production. A three year field study was initiated in 2013 to study the impact of biochar on soil carbon and nitrogen storage on an eroded Maddock soil series - Sandy, Mixed, Frigid Entic Hapludolls) and deposition Brookings clay loam (Fine-Silty, Mixed, Superactive, Frigid Pachic Hapludolls) landscape positions. Three biochars produced from corn stover (Zea mays L.), Ponderosa pine (Pinus ponderosa Lawson and C. Lawson) wood residue, and switchgrass (Panicum virgatum L.) were incorporated at 9.75 Mg ha-1 rate (≈7.5 cm soil depth and 1.3 g/cm3 soil bulk density) with a rototiller. The changes in chemical fractionation of soil carbon (soluble C, acid hydrolyzable C, total C, and δ13 C) and nitrogen (soluble N, acid hydrolyzable N, total N, and δ14 N) were monitored for two soil depths (0-7.5 and 7.5 - 15 cm). Soluble and acid hydrolyzable fractions of soil C and N were influenced by soil series and were not significantly affected by incorporation of biochars. Based on soil and plant samples to be collected in the fall of 2015, C and N budgets are being developed using isotopic and non-isotopic techniques. Laboratory studies showed that the mean residence time for biochars used in this study ranged from 400 to 666 years. Laboratory and field studies will be compared in the presentation.

  4. Investigating biodiversity trajectories using scenarios--lessons from two contrasting agricultural landscapes.

    PubMed

    Lindborg, Regina; Stenseke, Marie; Cousins, Sara A O; Bengtsson, Jan; Berg, Ake; Gustafsson, Tomas; Sjödin, N Erik; Eriksson, Ove

    2009-01-01

    Agriculture is the major land use at a global scale. In addition to food production, multifunctionality of landscapes, including values and ecosystem services like biodiversity, recreation and culture, is now focus for management. This study explores how a scenario approach, involving different stakeholders, may help to improve landscape management for biodiversity conservation. Local farmers and executives at the County Administrative Board were invited to discuss rural development and conditions for farmland biodiversity in two Swedish landscapes. The potential biodiversity for three future land use scenarios for the two landscapes was discussed: nature conservation, outdoor recreation and energy production, and compared with current and historical landscapes in each region. Analyses of habitat areas, connectedness and landscape diversity suggested that the energy and recreation scenarios had a negative impact on farmland biodiversity, whereas the nature conservation scenario, the current and historically reconstructed landscapes had a higher potential for biodiversity. The farmers appreciated the nature conservation scenario, but also the energy production scenario and they highlighted the need of increased subsidies for management of biodiversity. The farmers in the high production area were less interested in nature quality per se. The executives had similar opinions as the farmers, but disagreed on the advantages with energy production, as this would be in conflict with the high biodiversity and recreational values. The local physical and socio-economical conditions differ between landscapes and potentially shaped the stakeholders emotional attachment to the local environment, their opinions and decisions on how to manage the land. We stress the importance of incorporating local knowledge, visions and regional prerequisites for different land uses in conservation, since site and landscape specific planning for biodiversity together with a flexible subsidy

  5. Pollinator Interactions with Yellow Starthistle (Centaurea solstitialis) across Urban, Agricultural, and Natural Landscapes

    PubMed Central

    Leong, Misha; Kremen, Claire; Roderick, George K.

    2014-01-01

    Pollinator-plant relationships are found to be particularly vulnerable to land use change. Yet despite extensive research in agricultural and natural systems, less attention has focused on these interactions in neighboring urban areas and its impact on pollination services. We investigated pollinator-plant interactions in a peri-urban landscape on the outskirts of the San Francisco Bay Area, California, where urban, agricultural, and natural land use types interface. We made standardized observations of floral visitation and measured seed set of yellow starthistle (Centaurea solstitialis), a common grassland invasive, to test the hypotheses that increasing urbanization decreases 1) rates of bee visitation, 2) viable seed set, and 3) the efficiency of pollination (relationship between bee visitation and seed set). We unexpectedly found that bee visitation was highest in urban and agricultural land use contexts, but in contrast, seed set rates in these human-altered landscapes were lower than in natural sites. An explanation for the discrepancy between floral visitation and seed set is that higher plant diversity in urban and agricultural areas, as a result of more introduced species, decreases pollinator efficiency. If these patterns are consistent across other plant species, the novel plant communities created in these managed landscapes and the generalist bee species that are favored by human-altered environments will reduce pollination services. PMID:24466050

  6. Managing Nitrogen in Croplands: Implications for Increasing Ecosystem Services in Agricultural Landscapes

    NASA Astrophysics Data System (ADS)

    Jackson, L.

    2011-12-01

    Many agricultural landscapes in the temperate zone are dominated by agroecosystems that are managed with high inputs of agrochemicals, including synthetic nitrogen (N) fertilizers. The process of agricultural intensification increases crop production per unit area, but also often results in loss of environmental quality (such as N contamination of waters, eutrophication, atmospheric N deposition, and emissions of nitrous oxide (N2O), a potent greenhouse gas). Loss of biodiversity and its 'functional homogenization' is another concern. Not only does little land in these landscapes remain in natural ecosystems, but there are negative off-site impacts of intensive agriculture on non-target organisms. Segregating agroecosystems with high-input agricultural production from natural ecosystems (land sparing) is one view to support both food security and biodiversity conservation. But proponents of land sparing rarely address the loss of other ecosystem services, such as those related to environmental quality, health, and human well-being (e.g., livelihoods and cultural values). An emerging view is that increased reliance on ecological processes in agroecosystems ('ecological intensification') is more feasible when the landscape mosaic includes planned and unplanned biodiversity. This requires research on how to support multiple ecosystem services through the integration of agricultural production and biodiversity conservation in the same landscape, and how ecological and physico-chemical processes at various spatial scales are interlinked. It is an enormous challenge to increase reliance on ecological processes for N availability for crop productivity. There are skeptics who think that this will be detrimental for food security, despite benefits for other types of ecosystem services. Using examples from agricultural landscapes in California, mechanisms for ecologically-based N cycling will be discussed, such as: 1) increasing the reservoir of soil organic N and the

  7. Grass buffers for playas in agricultural landscapes: An annotated bibliography

    USGS Publications Warehouse

    Melcher, Cynthia P.; Skagen, Susan K.

    2005-01-01

    References on best management practices (BMPs) for agricultural lands were included because certain BMPs are crucial for informing decisions about buffer design/ effectiveness and overall playa ecology. We also included various papers that increase the spectrum of time over which buffer theories and practices have evolved. An unannotated section lists references that we did not prioritize for annotation and references that may be helpful but were beyond the scope of this document. Finally, we provide notes on conversations we had with scientists, land managers, and other buffer experts whom we consulted, and their contact information. We conclude the bibliography with appendices of common and scientific names of birds and plants and acronyms used in both the bibliography. In the annotations, italicized text signifies our own editorial remarks. Readers should also note that much of the work on buffers has been designed using English units of measure rather than metrics; in most cases, their results have been converted to metrics for publication, explaining the seemingly odd or irregular buffer widths and other parameters reported.

  8. An exhaustive inventory of coniferous trees in an agricultural landscape

    PubMed Central

    Rousselet, Jérôme; Roques, Alain; Garcia, Jacques

    2015-01-01

    Abstract Background Various species of forest trees are commonly used for ornamental purposes and are therefore frequently found in non-forest ecosystems. These trees constitute a significant component of the trees outside forests (TOF). Although increasingly recognized as prominent feature of agricultural lands and built-up areas, not much is known, however, about TOF since they are generally absent from forest inventories. New information In the present study, we focus on the coniferous tree species that constitute potential hosts for a forest defoliator, the pine processionary moth Thaumetopoea pityocampa Den. & Schiff. (Lepidoptera, Notodontidae). We carried out an exhaustive inventory of all pines (Pinus spp.), cedars (Cedrus spp.) and Douglas-fir (Pseudotsuga menziesii) in a 22 × 22 km study window located in the open-field region of Beauce in the centre of France. We recorded a total of 3834 individuals or small groups host trees corresponding a density of 7.9 occurrences per 100 ha. We provide the spatial coordinates of the points without differentiation between tree species. PMID:25733964

  9. Measuring and monitoring linear woody features in agricultural landscapes through earth observation data as an indicator of habitat availability

    NASA Astrophysics Data System (ADS)

    Pasher, J.; McGovern, M.; Putinski, V.

    2016-02-01

    The loss of natural habitats and the loss of biological diversity is a global problem affecting all ecosystems including agricultural landscapes. Indicators of biodiversity can provide standardized measures that make it easier to compare and communicate changes to an ecosystem. In agricultural landscapes the amount and variety of available habitat is directly correlated with biodiversity levels. Linear woody features (LWF), including hedgerows, windbreaks, shelterbelts as well as woody shrubs along fields, roads and watercourses, play a vital role in supporting biodiversity as well as serving a wide variety of other purposes in the ecosystem. Earth observation can be used to quantify and monitor LWF across the landscape. While individual features can be manually mapped, this research focused on the development of methods using line intersect sampling (LIS) for estimating LWF as an indicator of habitat availability in agricultural landscapes. The methods are accurate, efficient, repeatable and provide robust results. Methods were tested over 9.5 Mha of agricultural landscape in the Canadian Mixedwood Plains ecozone. Approximately 97,000 km of LWF were estimated across this landscape with results useable both at a regional reporting scale, as well as mapped across space for use in wildlife habitat modelling or other landscape management research. The LIS approach developed here could be employed at a variety of scales in particular for large regions and could be adapted for use as a national scale indicator of habitat availability in heavily disturbed agricultural landscape.

  10. Alternative scenarios of bioenergy crop production in an agricultural landscape and implications for bird communities.

    PubMed

    Blank, Peter J; Williams, Carol L; Sample, David W; Meehan, Timothy D; Turner, Monica G

    2016-01-01

    Increased demand and government mandates for bioenergy crops in the United States could require a large allocation of agricultural land to bioenergy feedstock production and substantially alter current landscape patterns. Incorporating bioenergy landscape design into land-use decision making could help maximize benefits and minimize trade-offs among alternative land uses. We developed spatially explicit landscape scenarios of increased bioenergy crop production in an 80-km radius agricultural landscape centered on a potential biomass-processing energy facility and evaluated the consequences of each scenario for bird communities. Our scenarios included conversion of existing annual row crops to perennial bioenergy grasslands and conversion of existing grasslands to annual bioenergy row crops. The scenarios explored combinations of four biomass crop types (three potential grassland crops along a gradient of plant diversity and one annual row crop [corn]), three land conversion percentages to bioenergy crops (10%, 20%, or 30% of row crops or grasslands), and three spatial configurations of biomass crop fields (random, clustered near similar field types, or centered on the processing plant), yielding 36 scenarios. For each scenario, we predicted the impact on four bird community metrics: species richness, total bird density, species of greatest conservation need (SGCN) density, and SGCN hotspots (SGCN birds/ha ≥ 2). Bird community metrics consistently increased with conversion of row crops to bioenergy grasslands and consistently decreased with conversion of grasslands to bioenergy row crops. Spatial arrangement of bioenergy fields had strong effects on the bird community and in some cases was more influential than the amount converted to bioenergy crops. Clustering grasslands had a stronger positive influence on the bird community than locating grasslands near the central plant or at random. Expansion of bioenergy grasslands onto marginal agricultural lands will

  11. Development and implementation of the Norwegian monitoring programme for agricultural landscapes.

    PubMed

    Dramstad, W E; Fjellstad, W J; Strand, G H; Mathiesen, H F; Engan, G; Stokland, J N

    2002-01-01

    This paper describes the development and implementation of the Norwegian monitoring programme for agricultural landscapes--the '3Q programme'. The main objective of the scheme is to indicate development trends in the agricultural landscape, and their consequences for spatial structure, biodiversity, cultural heritage and accessibility. The monitoring programme aims to give policy feedback and provide data to fulfill international reporting requirements. This paper describes the background to the programme and reasons behind the choice of methods. Results are presented to show the accuracy of the methods employed and the range of indicator values recorded in the programme. Strengths and limitations of the monitoring programme are discussed, and potential future improvements and developments are outlined. Although there remains a potential for methodological improvement, we stress the importance of establishing a baseline to enable the detection of development trends in a rapidly changing environment. PMID:11876074

  12. Effects of farm heterogeneity and methods for upscaling on modelled nitrogen losses in agricultural landscapes.

    PubMed

    Dalgaard, T; Hutchings, N; Dragosits, U; Olesen, J E; Kjeldsen, C; Drouet, J L; Cellier, P

    2011-11-01

    The aim of this study is to illustrate the importance of farm scale heterogeneity on nitrogen (N) losses in agricultural landscapes. Results are exemplified with a chain of N models calculating farm-N balances and distributing the N-surplus to N-losses (volatilisation, denitrification, leaching) and soil-N accumulation/release in a Danish landscape. Possible non-linearities in upscaling are assessed by comparing average model results based on (i) individual farm level calculations and (ii) averaged inputs at landscape level. Effects of the non-linearities that appear when scaling up from farm to landscape are demonstrated. Especially in relation to ammonia losses the non-linearity between livestock density and N-loss is significant (p > 0.999), with around 20-30% difference compared to a scaling procedure not taking this non-linearity into account. A significant effect of farm type on soil N accumulation (p > 0.95) was also identified and needs to be included when modelling landscape level N-fluxes and greenhouse gas emissions. PMID:21458123

  13. Ten principles for a landscape approach to reconciling agriculture, conservation, and other competing land uses

    PubMed Central

    Sayer, Jeffrey; Sunderland, Terry; Ghazoul, Jaboury; Pfund, Jean-Laurent; Sheil, Douglas; Meijaard, Erik; Venter, Michelle; Boedhihartono, Agni Klintuni; Day, Michael; Garcia, Claude; van Oosten, Cora; Buck, Louise E.

    2013-01-01

    Landscape approaches” seek to provide tools and concepts for allocating and managing land to achieve social, economic, and environmental objectives in areas where agriculture, mining, and other productive land uses compete with environmental and biodiversity goals. Here we synthesize the current consensus on landscape approaches. This is based on published literature and a consensus-building process to define good practice and is validated by a survey of practitioners. We find the landscape approach has been refined in response to increasing societal concerns about environment and development tradeoffs. Notably, there has been a shift from conservation-orientated perspectives toward increasing integration of poverty alleviation goals. We provide 10 summary principles to support implementation of a landscape approach as it is currently interpreted. These principles emphasize adaptive management, stakeholder involvement, and multiple objectives. Various constraints are recognized, with institutional and governance concerns identified as the most severe obstacles to implementation. We discuss how these principles differ from more traditional sectoral and project-based approaches. Although no panacea, we see few alternatives that are likely to address landscape challenges more effectively than an approach circumscribed by the principles outlined here. PMID:23686581

  14. Importance of wetland landscape structure to shorebirds wintering in an agricultural valley

    USGS Publications Warehouse

    Taft, Oriane W.; Haig, Susan M.

    2006-01-01

    Only recently has the influence of landscape structure on habitat use been a research focus in wetland systems. During non-breeding periods when food can be locally limited, wetland spatial pattern across a landscape may be of great importance in determining wetland use. We studied the influence of landscape structure on abundances of wintering Dunlin (Calidris alpina) and Killdeer (Charadrius vociferus) observed on wetlands in the agricultural Willamette Valley of Oregon, USA, during two winters (1999a??2000, 2000a??2001) of differing rainfall. We examined (1) shorebird use within a sample of 100 km2 regions differing in landscape structure (hectares of shorebird habitat [wet, unvegetated]) and (2) use of sites differing in landscape context (area of shorebird habitat within a species-defined radius). For use of sites, we also assessed the influence of two local characteristics: percent of soil exposed and area of wet habitat. We analyzed data using linear regression and information-theoretic modeling. During the dry winter (2000a??2001), Dunlin were attracted to regions with more wetland habitat and their abundances at sites increased with greater area of shorebird habitat within both the site and the surrounding landscape. In contrast, Dunlin abundances at sites were related to availability of habitat at only a local scale during the wet winter (1999a??2000). Regional habitat availability was of little importance in predicting Killdeer distributions, and Killdeer site use appeared unrelated to habitat distributions at both landscape and local scales. Results suggest prioritizing sites for conservation that are located in areas with high wetland coverage.

  15. LandSoil model application for erosion management in sustainable agricultural landscapes

    NASA Astrophysics Data System (ADS)

    Smetanova, Anna; Follain, Stéphane; Raclot, Damien; Le Bissonnais, Yves

    2016-04-01

    Soil erosion and land degradation can lead to irreversible changes and landscape degradation. In order to achieve the sustainability of agricultural landscapes, the land use scenarios might be developed and tested for their erosion mitigation effects. Despite the importance of the long-term scenarios (which are complicated by predictability of climate change in a small scale, its effect on change in soil properties and crops, and the societal behaviour of individual players), the management decision have to be applied already now. Therefore the short-term and medium term scenarios to achieve the most effective soil management and the least soil erosion footprint are necessary to develop. With increasing importance of individual large erosion events, the event-based models, considering soil properties and landscape structures appears to be suitable. The LandSoil model (Ciampalini et al., 2012) - a landscape evolution model operating at the field/small catchment scale, have been applied in order to analyse the effect of different soil erosion mitigation and connectivity management practices in two different Mediterranean catchments. In the soil erosion scenarios the proposed measures targeted soil erosion on field or on catchment scale, and the effect of different extreme events on soil redistribution was evaluated under different spatial designs. Anna Smetanová has received the support of the AgreenSkills fellowship (under grant agreement n°267196). R. Ciampalini, S. Follain, Y. Le Bissonnais, LandSoil: A model for analysing the impact of erosion on agricultural landscape evolution, Geomorphology, 175-176, 2012, 25-37.

  16. Predicted avian responses to bioenergy development scenarios in an intensive agricultural landscape

    USGS Publications Warehouse

    Uden, Daniel R.; Allen, Craig R.; Mitchell, Rob B.; McCoy, Tim D.; Guan, Qingfeng

    2015-01-01

    Conversion of native prairie to agriculture has increased food and bioenergy production but decreased wildlife habitat. However, enrollment of highly erodible cropland in conservation programs has compensated for some grassland loss. In the future, climate change and production of second-generation perennial biofuel crops could further transform agricultural landscapes and increase or decrease grassland area. Switchgrass (Panicum virgatum) is an alternative biofuel feedstock that may be economically and environmentally superior to maize (Zea mays) grain for ethanol production on marginally productive lands. Switchgrass could benefit farmers economically and increase grassland area, but there is uncertainty as to how conversions between rowcrops, switchgrass monocultures and conservation grasslands might occur and affect wildlife. To explore potential impacts on grassland birds, we developed four agricultural land-use change scenarios for an intensively cultivated landscape, each driven by potential future climatic changes and ensuing irrigation limitations, ethanol demand, commodity prices, and continuation of a conservation program. For each scenario, we calculated changes in area for landcover classes and predicted changes in grassland bird abundances. Overall, birds responded positively to the replacement of rowcrops with switchgrass and negatively to the conversion of conservation grasslands to switchgrass or rowcrops. Landscape context and interactions between climate, crop water use, and irrigation availability could influence future land-use, and subsequently, avian habitat quality and quantity. Switchgrass is likely to provide higher quality avian habitat than rowcrops but lower quality habitat than conservation grasslands, and therefore, may most benefit birds in heavily cultivated, irrigation dependent landscapes under warmer and drier conditions, where economic profitability may also encourage conversions to drought tolerant bioenergy feedstocks.

  17. Temporal dynamics influenced by global change: bee community phenology in urban, agricultural, and natural landscapes.

    PubMed

    Leong, Misha; Ponisio, Lauren C; Kremen, Claire; Thorp, Robbin W; Roderick, George K

    2016-03-01

    Urbanization and agricultural intensification of landscapes are important drivers of global change, which in turn have direct impacts on local ecological communities leading to shifts in species distributions and interactions. Here, we illustrate how human-altered landscapes, with novel ornamental and crop plant communities, result not only in changes to local community diversity of floral-dependent species, but also in shifts in seasonal abundance of bee pollinators. Three years of data on the spatio-temporal distributions of 91 bee species show that seasonal patterns of abundance and species richness in human-altered landscapes varied significantly less compared to natural habitats in which floral resources are relatively scarce in the dry summer months. These findings demonstrate that anthropogenic environmental changes in urban and agricultural systems, here mediated through changes in plant resources and water inputs, can alter the temporal dynamics of pollinators that depend on them. Changes in phenology of interactions can be an important, though frequently overlooked, mechanism of global change. PMID:26663622

  18. Ecosystem Services in Agricultural Landscapes: A Spatially Explicit Approach to Support Sustainable Soil Management

    PubMed Central

    Crossman, Neville D.; MacEwan, Richard J.; Wallace, D. Dugal; Bennett, Lauren T.

    2014-01-01

    Soil degradation has been associated with a lack of adequate consideration of soil ecosystem services. We demonstrate a broadly applicable method for mapping changes in the supply of two priority soil ecosystem services to support decisions about sustainable land-use configurations. We used a landscape-scale study area of 302 km2 in northern Victoria, south-eastern Australia, which has been cleared for intensive agriculture. Indicators representing priority soil services (soil carbon sequestration and soil water storage) were quantified and mapped under both a current and a future 25-year land-use scenario (the latter including a greater diversity of land uses and increased perennial crops and irrigation). We combined diverse methods, including soil analysis using mid-infrared spectroscopy, soil biophysical modelling, and geostatistical interpolation. Our analysis suggests that the future land-use scenario would increase the landscape-level supply of both services over 25 years. Soil organic carbon content and water storage to 30 cm depth were predicted to increase by about 11% and 22%, respectively. Our service maps revealed the locations of hotspots, as well as potential trade-offs in service supply under new land-use configurations. The study highlights the need to consider diverse land uses in sustainable management of soil services in changing agricultural landscapes. PMID:24616632

  19. Connectivity in an agricultural landscape as reflected by interpond movements of a freshwater turtle

    USGS Publications Warehouse

    Bowne, D.R.; Bowers, M.A.; Hines, J.E.

    2006-01-01

    Connectivity is a measure of how landscape features facilitate movement and thus is an important factor in species persistence in a fragmented landscape. The scarcity of empirical studies that directly quantify species movement and determine subsequent effects on population density have, however, limited the utility of connectivity measures in conservation planning. We undertook a 4-year study to calculate connectivity based on observed movement rates and movement probabilities for five age-sex classes of painted turtles (Chrysemys picta) inhabiting a pond complex in an agricultural landscape in northern Virginia (U.S.A.). We determined which variables influenced connectivity and the relationship between connectivity and subpopulation density. Interpatch distance and quality of habitat patches influenced connectivity but characteristics of the intervening matrix did not. Adult female turtles were more influenced by the habitat quality of recipient ponds than other age-sex classes. The importance of connectivity on spatial population dynamics was most apparent during a drought. Population density and connectivity were low for one pond in a wet year but dramatically increased as other ponds dried. Connectivity is an important component of species persistence in a heterogeneous landscape and is strongly dependent on the movement behavior of the species. Connectivity may reflect active selection or avoidance of particular habitat patches. The influence of habitat quality on connectivity has often been ignored, but our findings highlight its importance. Conservation planners seeking to incorporate connectivity measures into reserve design should not ignore behavior in favor of purely structural estimates of connectivity.

  20. Response of benthic algae to environmental gradients in an agriculturally dominated landscape

    USGS Publications Warehouse

    Munn, M.D.; Black, R.W.; Gruber, S.J.

    2002-01-01

    Benthic algal communities were assessed in an agriculturally dominated landscape in the Central Columbia Plateau, Washington, to determine which environmental variables best explained species distributions, and whether algae species optima models were useful in predicting specific water-quality parameters. Land uses in the study area included forest, range, urban, and agriculture. Most of the streams in this region can be characterized as open-channel systems influenced by intensive dryland (nonirrigated) and irrigated agriculture. Algal communities in forested streams were dominated by blue-green algae, with communities in urban and range streams dominated by diatoms. The predominance of either blue-greens or diatoms in agricultural streams varied greatly depending on the specific site. Canonical correspondence analysis (CCA) indicated a strong gradient effect of several key environmental variables on benthic algal community composition. Conductivity and % agriculture were the dominant explanatory variables when all sites (n = 24) were included in the CCA; water velocity replaced conductivity when the CCA included only agricultural and urban sites. Other significant explanatory variables included dissolved inorganic nitrogen (DIN), orthophosphate (OP), discharge, and precipitation. Regression and calibration models accurately predicted conductivity based on benthic algal communities, with OP having slightly lower predictability. The model for DIN was poor, and therefore may be less useful in this system. Thirty-four algal taxa were identified as potential indicators of conductivity and nutrient conditions, with most indicators being diatoms except for the blue-greens Anabaenasp. and Lyngbya sp.

  1. The influence of mistletoes on birds in an agricultural landscape of central Mexico

    NASA Astrophysics Data System (ADS)

    Zuria, Iriana; Castellanos, Ignacio; Gates, J. Edward

    2014-11-01

    Mistletoes are hemiparasitic flowering plants that function as keystone resources in forests and woodlands of temperate regions, where a positive relationship between mistletoe density and avian species richness has been observed. Mistletoes have been less studied in tropical regions and the relationship between birds and mistletoes has seldom been explored in tropical agricultural systems. Therefore, we studied the presence of infected trees and infection prevalence (i.e., number of parasitized trees/total number of trees) by Psittacanthus (Loranthaceae) mistletoes in 23 hedgerows located in an agricultural landscape of central Mexico during the dry and rainy seasons, and investigated the relationship between bird species richness and abundance and the abundance of mistletoes. We found a mean of 74 mistletoe plants per 100-m transect of only one species, Psittacanthus calyculatus. Thirty-one percent of the trees surveyed were infected and tree species differed in infection prevalence, mesquite (Prosopis laevigata) being the most infected species with 86% of the surveyed trees infected. For both seasons, we found a positive and significant association between bird species richness and number of mistletoe plants. The same pattern was observed for total bird abundance. Many resident and Neotropical migratory birds were observed foraging on mistletoes. Our results show that mistletoes are important in promoting a higher bird species richness and abundance in tropical agricultural landscapes.

  2. Pesticide concentrations in frog tissue and wetland habitats in a landscape dominated by agriculture.

    PubMed

    Smalling, Kelly L; Reeves, Rebecca; Muths, Erin; Vandever, Mark; Battaglin, William A; Hladik, Michelle L; Pierce, Clay L

    2015-01-01

    Habitat loss and exposure to pesticides are likely primary factors contributing to amphibian decline in agricultural landscapes. Conservation efforts have attempted to restore wetlands lost through landscape modifications to reduce contaminant loads in surface waters and providing quality habitat to wildlife. The benefits of this increased wetland area, perhaps especially for amphibians, may be negated if habitat quality is insufficient to support persistent populations. We examined the presence of pesticides and nutrients in water and sediment as indicators of habitat quality and assessed the bioaccumulation of pesticides in the tissue of two native amphibian species Pseudacris maculata (chorus frogs) and Lithobates pipiens (leopard frogs) at six wetlands (3 restored and 3 reference) in Iowa, USA. Restored wetlands are positioned on the landscape to receive subsurface tile drainage water while reference wetlands receive water from overland run-off and shallow groundwater sources. Concentrations of the pesticides frequently detected in water and sediment samples were not different between wetland types. The median concentration of atrazine in surface water was 0.2 μg/L. Reproductive abnormalities in leopard frogs have been observed in other studies at these concentrations. Nutrient concentrations were higher in the restored wetlands but lower than concentrations thought lethal to frogs. Complex mixtures of pesticides including up to 8 fungicides, some previously unreported in tissue, were detected with concentrations ranging from 0.08 to 1,500 μg/kg wet weight. No significant differences in pesticide concentrations were observed between species, although concentrations tended to be higher in leopard frogs compared to chorus frogs, possibly because of differences in life histories. Our results provide information on habitat quality in restored wetlands that will assist state and federal agencies, landowners, and resource managers in identifying and implementing

  3. Low-Intensity Agricultural Landscapes in Transylvania Support High Butterfly Diversity: Implications for Conservation

    PubMed Central

    Loos, Jacqueline; Dorresteijn, Ine; Hanspach, Jan; Fust, Pascal; Rakosy, László; Fischer, Joern

    2014-01-01

    European farmland biodiversity is declining due to land use changes towards agricultural intensification or abandonment. Some Eastern European farming systems have sustained traditional forms of use, resulting in high levels of biodiversity. However, global markets and international policies now imply rapid and major changes to these systems. To effectively protect farmland biodiversity, understanding landscape features which underpin species diversity is crucial. Focusing on butterflies, we addressed this question for a cultural-historic landscape in Southern Transylvania, Romania. Following a natural experiment, we randomly selected 120 survey sites in farmland, 60 each in grassland and arable land. We surveyed butterfly species richness and abundance by walking transects with four repeats in summer 2012. We analysed species composition using Detrended Correspondence Analysis. We modelled species richness, richness of functional groups, and abundance of selected species in response to topography, woody vegetation cover and heterogeneity at three spatial scales, using generalised linear mixed effects models. Species composition widely overlapped in grassland and arable land. Composition changed along gradients of heterogeneity at local and context scales, and of woody vegetation cover at context and landscape scales. The effect of local heterogeneity on species richness was positive in arable land, but negative in grassland. Plant species richness, and structural and topographic conditions at multiple scales explained species richness, richness of functional groups and species abundances. Our study revealed high conservation value of both grassland and arable land in low-intensity Eastern European farmland. Besides grassland, also heterogeneous arable land provides important habitat for butterflies. While butterfly diversity in arable land benefits from heterogeneity by small-scale structures, grasslands should be protected from fragmentation to provide

  4. Low-intensity agricultural landscapes in Transylvania support high butterfly diversity: implications for conservation.

    PubMed

    Loos, Jacqueline; Dorresteijn, Ine; Hanspach, Jan; Fust, Pascal; Rakosy, László; Fischer, Joern

    2014-01-01

    European farmland biodiversity is declining due to land use changes towards agricultural intensification or abandonment. Some Eastern European farming systems have sustained traditional forms of use, resulting in high levels of biodiversity. However, global markets and international policies now imply rapid and major changes to these systems. To effectively protect farmland biodiversity, understanding landscape features which underpin species diversity is crucial. Focusing on butterflies, we addressed this question for a cultural-historic landscape in Southern Transylvania, Romania. Following a natural experiment, we randomly selected 120 survey sites in farmland, 60 each in grassland and arable land. We surveyed butterfly species richness and abundance by walking transects with four repeats in summer 2012. We analysed species composition using Detrended Correspondence Analysis. We modelled species richness, richness of functional groups, and abundance of selected species in response to topography, woody vegetation cover and heterogeneity at three spatial scales, using generalised linear mixed effects models. Species composition widely overlapped in grassland and arable land. Composition changed along gradients of heterogeneity at local and context scales, and of woody vegetation cover at context and landscape scales. The effect of local heterogeneity on species richness was positive in arable land, but negative in grassland. Plant species richness, and structural and topographic conditions at multiple scales explained species richness, richness of functional groups and species abundances. Our study revealed high conservation value of both grassland and arable land in low-intensity Eastern European farmland. Besides grassland, also heterogeneous arable land provides important habitat for butterflies. While butterfly diversity in arable land benefits from heterogeneity by small-scale structures, grasslands should be protected from fragmentation to provide

  5. From "connecting the dots" to "threading the needle:" The challenges ahead in managing agricultural landscapes for environmental quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Non point source pollution from agriculture is one of the most challenging problems facing society. In this book chapter, we briefly review the development of “landscape thinking” in agriculture and how this has been incorporated into the USDA Conservation Effects Assessment Program (CEAP). We pre...

  6. The Agricultural Policy/Environmental Extender (Apex) Model: An Emerging Tool for Landscape and Watershed Environmental Analyses

    SciTech Connect

    Gassman, Philip W.; Williams, Jimmy R.; Wang, Xiuying; Saleh, Ali; Osei, Edward; Hauck, Larry; Izaurralde, Roberto C.; Flowers, Joan

    2010-06-01

    The Agricultural Policy Environmental eXtender (APEX) model was developed by the Blacklands Research and Extension Center in Temple, Texas. APEX is a flexible and dynamic tool that is capable of simulating a wide array of management practices, cropping systems, and other land uses across a broad range of agricultural landscapes, including whole farms and small watersheds.

  7. Fluxes of carbon dioxide and methane from diverse aquatic environments in an agricultural landscape

    NASA Astrophysics Data System (ADS)

    Stanley, E. H.; Crawford, J. T.; Loken, L. C.; Casson, N. J.; Gubbins, N. J.; Oliver, S. K.

    2014-12-01

    The contribution of aquatic environments to landscape carbon cycling is particularly apparent in carbon- and water-rich regions. Such areas arguably represent an end member in terms of the relative significance of aquatic carbon cycling, while dry, carbon-poor zones are the likely opposing end member. Not surprisingly, most limnological attention has focused on these former regions, leaving open questions as to how aquatic systems in other locales influence larger-scale carbon dynamics. This includes human-dominated landscapes where agricultural and urban land uses can fundamentally alter carbon dynamics. Surveys of streams, ponds, and lakes in a southern Wisconsin landscape highlight three findings relevant to understanding the role of these aquatic systems in larger-scale carbon dynamics. First, streams and ponds had unexpectedly high summertime concentrations in and fluxes of CO2 and CH4. These values were approximately an order of magnitude greater than for less disturbed, forest and wetland-dominated landscapes in northern Wisconsin. Second, while mean C gas concentrations in lakes were lower than in streams and ponds, detailed spatial measurements demonstrate variability in surface water CO2 (43-1090 ppm pCO2) and CH4 (6-839 ppm pCH4) within a lake on a single day is similar to that observed among 25 streams included in our survey (260-6000 ppm pCO2; 50-600 ppm pCH4). This small-scale heterogeneity highlights a basic challenge for upscaling site-specific data collected at one or a few points to the whole lake and across lakes. Third, while agricultural and urban ecosystems are not necessarily carbon-rich environments, area-specific carbon storage in streams and ponds is substantial (up to 3000-5000 g C per m2). Further, carbon storage was strongly related to CH4 concentrations in streams, as C-rich sediments provided both an environment and substrate to fuel methanogenesis. The picture that emerges of C processing in aquatic environments throughout this human

  8. Nutrient Mitigation Efficiency in Agricultural Drainage Ditches: An Influence of Landscape Management.

    PubMed

    Iseyemi, Oluwayinka O; Farris, Jerry L; Moore, Matthew T; Choi, Seo-Eun

    2016-06-01

    Drainage systems are integral parts of agricultural landscapes and have the ability to intercept nutrient loading from runoff to surface water. This study investigated nutrient removal efficiency within replicated experimental agricultural drainage ditches during a simulated summer runoff event. Study objectives were to examine the influence of routine mowing of vegetated ditches on nutrient mitigation and to assess spatial transformation of nutrients along ditch length. Both mowed and unmowed ditch treatments decreased NO3 (-)-N by 79 % and 94 % and PO4 (3-) by 95 % and 98 %, respectively, with no significant difference in reduction capacities between the two treatments. This suggests occasional ditch mowing as a management practice would not undermine nutrient mitigation capacity of vegetated drainage ditches. PMID:27022936

  9. Mapping and determinism of soil microbial community distribution across an agricultural landscape

    PubMed Central

    Constancias, Florentin; Terrat, Sébastien; Saby, Nicolas P A; Horrigue, Walid; Villerd, Jean; Guillemin, Jean-Philippe; Biju-Duval, Luc; Nowak, Virginie; Dequiedt, Samuel; Ranjard, Lionel; Chemidlin Prévost-Bouré, Nicolas

    2015-01-01

    Despite the relevance of landscape, regarding the spatial patterning of microbial communities and the relative influence of environmental parameters versus human activities, few investigations have been conducted at this scale. Here, we used a systematic grid to characterize the distribution of soil microbial communities at 278 sites across a monitored agricultural landscape of 13 km². Molecular microbial biomass was estimated by soil DNA recovery and bacterial diversity by 16S rRNA gene pyrosequencing. Geostatistics provided the first maps of microbial community at this scale and revealed a heterogeneous but spatially structured distribution of microbial biomass and diversity with patches of several hundreds of meters. Variance partitioning revealed that both microbial abundance and bacterial diversity distribution were highly dependent of soil properties and land use (total variance explained ranged between 55% and 78%). Microbial biomass and bacterial richness distributions were mainly explained by soil pH and texture whereas bacterial evenness distribution was mainly related to land management. Bacterial diversity (richness, evenness, and Shannon index) was positively influenced by cropping intensity and especially by soil tillage, resulting in spots of low microbial diversity in soils under forest management. Spatial descriptors also explained a small but significant portion of the microbial distribution suggesting that landscape configuration also shapes microbial biomass and bacterial diversity. PMID:25833770

  10. Nectar resource limitation affects butterfly flight performance and metabolism differently in intensive and extensive agricultural landscapes.

    PubMed

    Lebeau, Julie; Wesselingh, Renate A; Van Dyck, Hans

    2016-05-11

    Flight is an essential biological ability of many insects, but is energetically costly. Environments under rapid human-induced change are characterized by habitat fragmentation and may impose constraints on the energy income budget of organisms. This may, in turn, affect locomotor performance and willingness to fly. We tested flight performance and metabolic rates in meadow brown butterflies (Maniola jurtina) of two contrasted agricultural landscapes: intensively managed, nectar-poor (IL) versus extensively managed, nectar-rich landscapes (EL). Young female adults were submitted to four nectar treatments (i.e. nectar quality and quantity) in outdoor flight cages. IL individuals had better flight capacities in a flight mill and had lower resting metabolic rates (RMR) than EL individuals, except under the severest treatment. Under this treatment, RMR increased in IL individuals, but decreased in EL individuals; flight performance was maintained by IL individuals, but dropped by a factor 2.5 in EL individuals. IL individuals had more canalized (i.e. less plastic) responses relative to the nectar treatments than EL individuals. Our results show significant intraspecific variation in the locomotor and metabolic response of a butterfly to different energy income regimes relative to the landscape of origin. Ecophysiological studies help to improve our mechanistic understanding of the eco-evolutionary impact of anthropogenic environments on rare and widespread species. PMID:27147100

  11. Mapping and determinism of soil microbial community distribution across an agricultural landscape.

    PubMed

    Constancias, Florentin; Terrat, Sébastien; Saby, Nicolas P A; Horrigue, Walid; Villerd, Jean; Guillemin, Jean-Philippe; Biju-Duval, Luc; Nowak, Virginie; Dequiedt, Samuel; Ranjard, Lionel; Chemidlin Prévost-Bouré, Nicolas

    2015-06-01

    Despite the relevance of landscape, regarding the spatial patterning of microbial communities and the relative influence of environmental parameters versus human activities, few investigations have been conducted at this scale. Here, we used a systematic grid to characterize the distribution of soil microbial communities at 278 sites across a monitored agricultural landscape of 13 km². Molecular microbial biomass was estimated by soil DNA recovery and bacterial diversity by 16S rRNA gene pyrosequencing. Geostatistics provided the first maps of microbial community at this scale and revealed a heterogeneous but spatially structured distribution of microbial biomass and diversity with patches of several hundreds of meters. Variance partitioning revealed that both microbial abundance and bacterial diversity distribution were highly dependent of soil properties and land use (total variance explained ranged between 55% and 78%). Microbial biomass and bacterial richness distributions were mainly explained by soil pH and texture whereas bacterial evenness distribution was mainly related to land management. Bacterial diversity (richness, evenness, and Shannon index) was positively influenced by cropping intensity and especially by soil tillage, resulting in spots of low microbial diversity in soils under forest management. Spatial descriptors also explained a small but significant portion of the microbial distribution suggesting that landscape configuration also shapes microbial biomass and bacterial diversity. PMID:25833770

  12. Edges in agricultural landscapes: species interactions and movement of natural enemies.

    PubMed

    Macfadyen, Sarina; Muller, Warren

    2013-01-01

    Agricultural landscapes can be characterized as a mosaic of habitat patches interspersed with hostile matrix, or as a gradient of patches ranging from suitable to unsuitable for different species. Arthropods moving through these landscapes encounter a range of edges, with different permeability. Patches of native vegetation in these landscapes may support natural enemies of crop pests by providing alternate hosts for parasitic wasps and/or acting as a source for predatory insects. We test this by quantifying species interactions and measuring movement across different edge-types. A high diversity of parasitoid species used hosts in the native vegetation patches, however we recorded few instances of the same parasitoid species using hosts in both the native vegetation and the crop (canola). However, we did find overall greater densities of parasitoids moving from native vegetation into the crop. Of the parasitoid groups examined, parasitoids of aphids (Braconidae: Aphidiinae) frequently moved from native vegetation into canola. In contrast, parasitoids of caterpillars (Braconidae: Microgastrinae) moved commonly from cereal fields into canola. Late season samples showed both aphids and parasitoids moving frequently out of native vegetation, in contrast predators moved less commonly from native vegetation (across the whole season). The season-long net advantage or disadvantage of native vegetation for pest control services is therefore difficult to evaluate. It appears that the different edge-types alter movement patterns of natural enemies more so than herbivorous pest species, and this may impact pest control services. PMID:23555737

  13. Frugivorous bats maintain functional habitat connectivity in agricultural landscapes but rely strongly on natural forest fragments.

    PubMed

    Ripperger, Simon P; Kalko, Elisabeth K V; Rodríguez-Herrera, Bernal; Mayer, Frieder; Tschapka, Marco

    2015-01-01

    Anthropogenic changes in land use threaten biodiversity and ecosystem functioning by the conversion of natural habitat into agricultural mosaic landscapes, often with drastic consequences for the associated fauna. The first step in the development of efficient conservation plans is to understand movement of animals through complex habitat mosaics. Therefore, we studied ranging behavior and habitat use in Dermanura watsoni (Phyllostomidae), a frugivorous bat species that is a valuable seed disperser in degraded ecosystems. Radio-tracking of sixteen bats showed that the animals strongly rely on natural forest. Day roosts were exclusively located within mature forest fragments. Selection ratios showed that the bats foraged selectively within the available habitat and positively selected natural forest. However, larger daily ranges were associated with higher use of degraded habitats. Home range geometry and composition of focal foraging areas indicated that wider ranging bats performed directional foraging bouts from natural to degraded forest sites traversing the matrix over distances of up to three hundred meters. This behavior demonstrates the potential of frugivorous bats to functionally connect fragmented areas by providing ecosystem services between natural and degraded sites, and highlights the need for conservation of natural habitat patches within agricultural landscapes that meet the roosting requirements of bats. PMID:25830222

  14. Frugivorous Bats Maintain Functional Habitat Connectivity in Agricultural Landscapes but Rely Strongly on Natural Forest Fragments

    PubMed Central

    Ripperger, Simon P.; Kalko, Elisabeth K. V.; Rodríguez-Herrera, Bernal; Mayer, Frieder; Tschapka, Marco

    2015-01-01

    Anthropogenic changes in land use threaten biodiversity and ecosystem functioning by the conversion of natural habitat into agricultural mosaic landscapes, often with drastic consequences for the associated fauna. The first step in the development of efficient conservation plans is to understand movement of animals through complex habitat mosaics. Therefore, we studied ranging behavior and habitat use in Dermanura watsoni (Phyllostomidae), a frugivorous bat species that is a valuable seed disperser in degraded ecosystems. Radio-tracking of sixteen bats showed that the animals strongly rely on natural forest. Day roosts were exclusively located within mature forest fragments. Selection ratios showed that the bats foraged selectively within the available habitat and positively selected natural forest. However, larger daily ranges were associated with higher use of degraded habitats. Home range geometry and composition of focal foraging areas indicated that wider ranging bats performed directional foraging bouts from natural to degraded forest sites traversing the matrix over distances of up to three hundred meters. This behavior demonstrates the potential of frugivorous bats to functionally connect fragmented areas by providing ecosystem services between natural and degraded sites, and highlights the need for conservation of natural habitat patches within agricultural landscapes that meet the roosting requirements of bats. PMID:25830222

  15. Identifying Landscape Areas Prone to Generating Storm Runoff in Central New York Agricultural Fields

    NASA Astrophysics Data System (ADS)

    Hofmeister, K.; Walter, M. T.

    2015-12-01

    Nonpoint source (NPS) pollution continues to be a leading cause of surface water degradation, especially in agricultural areas. In humid regions where variable source area (VSA) hydrology dominates storm runoff, NPS pollution is generated where VSAs coincide with polluting activities. Mapping storm runoff risks could allow for more precise and informed targeting of NPS pollution mitigation practices in agricultural landscapes. Topographic wetness indices (TWI) provide good approximations of relative soil moisture patterns and relative storm runoff risks. Simulation models are typically used in conjunction with TWIs to quantify VSA behavior. In this study we use empirically derived relationships between TWI values, volumetric water content (VWC) and rainfall frequencies to develop runoff probability maps. Rainfall and soil VWC were measured across regionally representative agricultural areas in central New York over three years (2012-2015) to determine the volume of runoff generated from agricultural fields in the area. We assumed the threshold for storm runoff occurs when the combination of antecedent soil water and rainfall are sufficient to saturate the soil. We determined that approximately 50% of the storm runoff volume is generated from 10% of the land area during spring, summer, and autumn seasons, while the risk of storm runoff generation is higher in the spring and autumn seasons than in the summer for the same area of land.

  16. An insight into space and remote sensing technologies concerning agriculture and landscape analysis

    NASA Astrophysics Data System (ADS)

    Cuca, Branka; Barazzetti, Luigi; Brumana, Raffaella; Previtali, Mattia

    2015-06-01

    Remote sensing and space technologies are increasingly called to offer innovative solutions for current challenges induced by climatic and global change. One of the main priorities of the European Space Policy regards the economic independence of the old continent in this sector. In terms of research and innovation this inevitably leads to numerous attempts in having independent market of services that would tackle specific needs of the citizens. Agriculture, for example, is one of the sectors majorly subsidized by European funds on national, regional and local level, with the aim to foster a more productive and sustainable development. Due to a large territorial scale at which agricultural phenomena are observed, and thus the spatial resolution required, it is also one of the main sectors that has been monitored from space over the past 30 years. In fact, one of the main missions of USA Landsat satellites was to provide a continuous and systematic overview of the globe for the purposes of an effective monitoring of the environment. This paper represents an overview of the ongoing initiatives in Space research done for the field of agriculture and landscape monitoring. In particular, the paper looks into the future possibilities that will be offered by full, open and free-of-charge data arriving from ongoing Copernicus missions and the contribution of Sentinel satellites to the agricultural sector.

  17. Downstream approaches to phosphorus management in agricultural landscapes: regional applicability and use.

    PubMed

    Kröger, R; Dunne, E J; Novak, J; King, K W; McLellan, E; Smith, D R; Strock, J; Boomer, K; Tomer, M; Noe, G B

    2013-01-01

    This review provides a critical overview of conservation practices that are aimed at improving water quality by retaining phosphorus (P) downstream of runoff genesis. The review is structured around specific downstream practices that are prevalent in various parts of the United States. Specific practices that we discuss include the use of controlled drainage, chemical treatment of waters and soils, receiving ditch management, and wetlands. The review also focuses on the specific hydrology and biogeochemistry associated with each of those practices. The practices are structured sequentially along flowpaths as you move through the landscape, from the edge-of-field, to adjacent aquatic systems, and ultimately to downstream P retention. Often practices are region specific based on geology, cropping practices, and specific P related problems and thus require a right practice, and right place mentality to management. Each practice has fundamental P transport and retention processes by systems that can be optimized by management with the goal of reducing downstream P loading after P has left agricultural fields. The management of P requires a system-wide assessment of the stability of P in different biogeochemical forms (particulate vs. dissolved, organic vs. inorganic), in different storage pools (soil, sediment, streams etc.), and under varying biogeochemical and hydrological conditions that act to convert P from one form to another and promote its retention in or transport out of different landscape components. There is significant potential of hierarchically placing practices in the agricultural landscape and enhancing the associated P mitigation. But an understanding is needed of short- and long-term P retention mechanisms within a certain practice and incorporating maintenance schedules if necessary to improve P retention times and minimize exceeding retention capacity. PMID:23178830

  18. Floral resource limitation severely reduces butterfly survival, condition and flight activity in simplified agricultural landscapes.

    PubMed

    Lebeau, Julie; Wesselingh, Renate A; Van Dyck, Hans

    2016-02-01

    Agricultural intensification has a strong negative impact on farmland biodiversity (including flower-visiting insects), but understanding the mechanisms involved in this requires experimental work. We document the impact of nectar limitation on the performance of a flower-visiting insect, the meadow brown butterfly Maniola jurtina. We conducted two types of experiments: a field experiment in agricultural landscapes with grasslands of different management intensity and an experiment in outdoor flight cages in which the nectar supply was simulated. For the field experiment, we introduced an array of nectar resources in intensively managed, nectar-poor meadows and in extensively managed, flower-rich grasslands and counted flower visitors. Despite higher butterfly abundance in the extensive meadows, our introduced nectar sources were more frequently visited in intensive meadows, indicating the lack of floral resources. The 48-h confinement under nectar-poor conditions in the flight cages had a strong negative effect on body condition, flight activity and lifetime survival compared to butterflies under nectar-rich conditions. Female lifespan was reduced by 22% and male lifespan even by 43%. Agricultural landscapes that provide limited amounts of floral nectar, and no high-quality, preferred nectar sources relative to the needs of the flower-visiting species, may create ecological sinks. Regards an insect's performance, the simple presence of nectar is not necessarily functionally adequate. The effectiveness of agri-environmental schemes for flower-visiting insects (e.g. flower strips) could be improved based on ecological and evolutionary insights on the effects of specific nectar quantities and qualities. PMID:26541442

  19. Influence of subsurface drainage on quantity and quality of dissolved organic matter export from agricultural landscapes

    NASA Astrophysics Data System (ADS)

    Dalzell, Brent J.; King, Jennifer Y.; Mulla, David J.; Finlay, Jacques C.; Sands, Gary R.

    2011-06-01

    Despite its importance for aquatic ecosystem function and watershed carbon budgets, little is known about how land use influences dissolved organic matter (DOM) export. We investigated the influence of subsurface soil drainage, widespread in the Midwestern United States, on DOM export from agricultural fields designed to drain water at either 13 mm d-1 (conventional) or 51 mm d-1 (intense). Intense drainage exported 55% (±22%) more dissolved organic carbon (DOC) per year than conventional drainage due to both increased concentration and water yield. DOC export from plots was strongly dependent on precipitation and showed considerable interannual variability. Mean DOC concentrations in drainage water were low (1.62 and 1.87 mg L-1 for conventional and intense treatments), and fluorescence index (FI) measurements showed that it had a microbial source with little evidence of terrestrially derived material, suggesting that flow through deeper, organic-poor soil horizons is important in regulating DOC export from these plots. We compared DOM in subsurface drains with downstream ditch and stream sites. Increases in DOC concentration and molecular weight accompanied by decreasing FI values at downstream sites showed that streams gain a large amount of terrestrially derived DOM during base flow transport through agricultural landscapes, probably from riparian zones. These results show that DOM compositional characteristics change with catchment area and that the relevant observation scale for DOM dynamics is likely to vary among watersheds. This study also demonstrates that land management practices can directly affect DOC via changes to water flow paths. These results are critical for improving model estimates of DOM export from agricultural landscapes as well as predicting how DOC export will respond to changing land use and climate.

  20. Contrasting perceptions of anthropogenic coastal agricultural landscape meanings and management in Italy and Canada

    NASA Astrophysics Data System (ADS)

    Targetti, Stefano; Sherren, Kate; Raggi, Meri; Viaggi, Davide

    2016-04-01

    The Anthropocene concept entails the idea that humans have become the most influential driving factor on the environment. In this context, it is useful to get insights from coastal areas that are affected by a huge impact of human activities in shaping the territory, are prone to several threats linked with climate change, and featured by interlinked economic, cultural and social systems. We compare evidence from three different methods focusing on the perceptions of coastal agricultural landscapes: i) a survey focusing on residents' perceptions of local rural landscape elements; ii) an expert-elicitation multicriteria exercise (Analytic Network Process) focusing on the relationship between economic actors, ecosystem services and local competitiveness; and iii) a Q-methodology survey to identify public discourses concerning management alternatives. The methods were applied in two coastal case studies characterized by land drainage, shoreline barriers and coastal armoring that represent high cultural heritage; created by humans they rely on active management to persist. Moreover, in both the case studies concerns have been raised about the role of agriculture in the rural development context and the perspectives of local stakeholders towards the management of the reclaimed lands. The first area is located on the southern side of the Po River Delta (Emilia Romagna, Italy). The area was reclaimed during the 19th and 20th centuries for agricultural production and is now characterized by intensive agriculture in the hinterlands, an urbanised coastal area with a developed tourism sector, and the presence of remnant wetlands which are mostly included in the Po Delta Natural Park (covering around 30% of the case study). The second area is located in the dykelands of the Bay of Fundy (Nova Scotia, Canada) whose origins go back to the 17th Century when French settlers built the first dykes to reclaim salt marshes for farmland. While some are still farmed, a range of

  1. Rapid genetic turnover in populations of the insect pest Bemisia tabaci Middle East: Asia Minor 1 in an agricultural landscape.

    PubMed

    Dinsdale, A; Schellhorn, N A; De Barro, P; Buckley, Y M; Riginos, C

    2012-10-01

    Organisms differ greatly in dispersal ability, and landscapes differ in amenability to an organism's movement. Thus, landscape structure and heterogeneity can affect genetic composition of populations. While many agricultural pests are known for their ability to disperse rapidly, it is unclear how fast and over what spatial scale insect pests might respond to the temporally dynamic agricultural landscapes they inhabit. We used population genetic analyses of a severe crop pest, a member of the Bemisia tabaci (Hemiptera: Sternorrhyncha: Aleyrodoidea: Aleyrodidea) cryptic species complex known as Middle East-Asia Minor 1 (commonly known as biotype B), to estimate spatial and temporal genetic diversity over four months of the 2006-2007 summer growing season. We examined 559 individuals from eight sites, which were scored for eight microsatellite loci. Temporal genetic structure greatly exceeded spatial structure. There was significant temporal change in local genetic composition from the beginning to the end of the season accompanied by heterozygote deficits and inbreeding. This temporal structure suggests entire cohorts of pests can occupy a large and variable agricultural landscape but are rapidly replaced. These rapid genetic fluctuations reinforce the concept that agricultural landscapes are dynamic mosaics in time and space and may contribute to better decisions for pest and insecticide resistance management. PMID:22420748

  2. Changes in soil fungal communities across a landscape of agricultural soil land-uses

    NASA Astrophysics Data System (ADS)

    Berthrong, S. T.; Buckley, D. H.; Drinkwater, L. E.

    2012-12-01

    Agricultural management is a major driver of changes in soils and their resident microbial communities, but we do not yet have a clear picture of how agriculture affects soil fungi. This is an important gap in our knowledge since fungi play an important role in many soil processes. Previous research has suggested that organic management practices can lead to an increase in soil fungal community diversity, which could have impacts on soil processes and alter the long term trajectory of soil quality in agricultural systems. Also, the relationship between management effects, biogeography, and soil fungi is not clear. The biogeography of macroscopic species is well described by taxa-area relationships and distance decay models, and recent research has suggested that certain subsets of fungi (e.g. AMF, litter sapotrophs) demonstrate similar patterns. However there is little information on how soil fungi as a whole are distributed across a landscape with soils under different managements. The goal of this project was to examine how different management practices alter soil fungal communities across a landscape of agricultural fields in upstate NY. We asked several specific questions: 1) Do different types of agricultural land-uses lead to divergent or convergent communities of soil fungi? 2) If soil type is held constant, do soil fungal communities diverge with geographic distance? 3) What are the major fungal groups that change in response to soil management, and are they cosmopolitan or endemic across the landscape? We studied these questions across agricultural fields in upstate NY that ranged from conventional corn, organic grains/corn, and long-term pasture. We sampled four fields (conventional, 10 and 20 year organic, and pasture) that had identical soils types and ranged from 100 m to 4 km apart. We utilized a multiplexed pyrosequencing approach on genomic DNA to analyze the structure of the soils' fungal communities. This approach allowed us to study soil fungi

  3. Stream Channel Change in an Intensively Managed Agricultural Landscape: Implications for Critical Zone Processes

    NASA Astrophysics Data System (ADS)

    Lewis, Q. W.; Rhoads, B. L.; Andresen, W.

    2014-12-01

    During the Anthropocene, humans have had a substantial impact on fluvial systems throughout the world. Perhaps nowhere is the human imprint on stream systems more pronounced than in the intensively managed agriculture landscapes of the midwestern United States. This study examines changes in the structure of the stream network and in the planform dynamics of stream channels within the upper Sangamon River basin in Illinois - a watershed that is part of a new Critical Zone Observatory focusing on intensively managed landscapes (IML-CZO). The research explores changes in network structure as the landscape changed from prairie and forest into drained farmland dominated by row crop agriculture. It also documents the planform dynamics of stream and river channels over the past 80 to 100 years. Results show that the spatial extent of channels within the stream network expanded greatly as land was cleared and drained for agriculture. Expansion of the network into headwater portions of the watershed occurred through the construction of drainage ditches that serve as outlets for tile drainage systems underlying relatively flat, poorly drained farmland. Analysis of planform dynamics reveals that most of these drainage ditches have not changed alignment since initial construction. Although drainage ditches are maintained by local drainage districts, these human-created channels also are remarkably resistant to change in planform over time. The major type of planform change in headwater streams involves artificial straightening of meandering channels to expand the extent of drainage channels. Many sections of the meandering Sangamon River are heavily forested and exhibit little or no planform change over the past 80-100 years. Sections that are most active tend to occur where forest cover is less prevalent due to clearing of trees for pasture or cropland. Overall, the results demonstrate the pronounced imprint of humans on the structure and planform dynamics of a fluvial

  4. REDD+ and climate smart agriculture in landscapes: A case study in Vietnam using companion modelling.

    PubMed

    Salvini, G; Ligtenberg, A; van Paassen, A; Bregt, A K; Avitabile, V; Herold, M

    2016-05-01

    Finding land use strategies that merge land-based climate change mitigation measures and adaptation strategies is still an open issue in climate discourse. This article explores synergies and trade-offs between REDD+, a scheme that focuses mainly on mitigation through forest conservation, with "Climate Smart Agriculture", an approach that emphasizes adaptive agriculture. We introduce a framework for ex-ante assessment of the impact of land management policies and interventions and for quantifying their impacts on land-based mitigation and adaptation goals. The framework includes a companion modelling (ComMod) process informed by interviews with policymakers, local experts and local farmers. The ComMod process consists of a Role-Playing Game with local farmers and an Agent Based Model. The game provided a participatory means to develop policy and climate change scenarios. These scenarios were then used as inputs to the Agent Based Model, a spatially explicit model to simulate landscape dynamics and the associated carbon emissions over decades. We applied the framework using as case study a community in central Vietnam, characterized by deforestation for subsistence agriculture and cultivation of acacias as a cash crop. The main findings show that the framework is useful in guiding consideration of local stakeholders' goals, needs and constraints. Additionally the framework provided beneficial information to policymakers, pointing to ways that policies might be re-designed to make them better tailored to local circumstances and therefore more effective in addressing synergistically climate change mitigation and adaptation objectives. PMID:26921566

  5. Vegetation Water Content Mapping in a Diverse Agricultural Landscape: National Airborne Field Experiment 2006

    NASA Technical Reports Server (NTRS)

    Cosh, Michael H.; Jing Tao; Jackson, Thomas J.; McKee, Lynn; O'Neill, Peggy

    2011-01-01

    Mapping land cover and vegetation characteristics on a regional scale is critical to soil moisture retrieval using microwave remote sensing. In aircraft-based experiments such as the National Airborne Field Experiment 2006 (NAFE 06), it is challenging to provide accurate high resolution vegetation information, especially on a daily basis. A technique proposed in previous studies was adapted here to the heterogenous conditions encountered in NAFE 06, which included a hydrologically complex landscape consisting of both irrigated and dryland agriculture. Using field vegetation sampling and ground-based reflectance measurements, the knowledge base for relating the Normalized Difference Water Index (NDWI) and the vegetation water content was extended to a greater diversity of agricultural crops, which included dryland and irrigated wheat, alfalfa, and canola. Critical to the generation of vegetation water content maps, the land cover for this region was determined from satellite visible/infrared imagery and ground surveys with an accuracy of 95.5% and a kappa coefficient of 0.95. The vegetation water content was estimated with a root mean square error of 0.33 kg/sq m. The results of this investigation contribute to a more robust database of global vegetation water content observations and demonstrate that the approach can be applied with high accuracy. Keywords: Vegetation, field experimentation, thematic mapper, NDWI, agriculture.

  6. Landscape Planning for Agricultural Nonpoint Source Pollution Reduction I: A Geographical Allocation Framework

    NASA Astrophysics Data System (ADS)

    Diebel, Matthew W.; Maxted, Jeffrey T.; Nowak, Peter J.; Vander Zanden, M. Jake

    2008-11-01

    Agricultural nonpoint source pollution remains a persistent environmental problem, despite the large amount of money that has been spent on its abatement. At local scales, agricultural best management practices (BMPs) have been shown to be effective at reducing nutrient and sediment inputs to surface waters. However, these effects have rarely been found to act in concert to produce measurable, broad-scale improvements in water quality. We investigated potential causes for this failure through an effort to develop recommendations for the use of riparian buffers in addressing nonpoint source pollution in Wisconsin. We used frequency distributions of phosphorus pollution at two spatial scales (watershed and field), along with typical stream phosphorus (P) concentration variability, to simulate benefit/cost curves for four approaches to geographically allocating conservation effort. The approaches differ in two ways: (1) whether effort is aggregated within certain watersheds or distributed without regard to watershed boundaries (dispersed), and (2) whether effort is targeted toward the most highly P-polluting fields or is distributed randomly with regard to field-scale P pollution levels. In realistic implementation scenarios, the aggregated and targeted approach most efficiently improves water quality. For example, with effort on only 10% of a model landscape, 26% of the total P load is retained and 25% of watersheds significantly improve. Our results indicate that agricultural conservation can be more efficient if it accounts for the uneven spatial distribution of potential pollution sources and the cumulative aspects of environmental benefits.

  7. Fine-scale spatial genetic structure of common and declining bumble bees across an agricultural landscape.

    PubMed

    Dreier, Stephanie; Redhead, John W; Warren, Ian A; Bourke, Andrew F G; Heard, Matthew S; Jordan, William C; Sumner, Seirian; Wang, Jinliang; Carvell, Claire

    2014-07-01

    Land-use changes have threatened populations of many insect pollinators, including bumble bees. Patterns of dispersal and gene flow are key determinants of species' ability to respond to land-use change, but have been little investigated at a fine scale (<10 km) in bumble bees. Using microsatellite markers, we determined the fine-scale spatial genetic structure of populations of four common Bombus species (B. terrestris, B. lapidarius, B. pascuorum and B. hortorum) and one declining species (B. ruderatus) in an agricultural landscape in Southern England, UK. The study landscape contained sown flower patches representing agri-environment options for pollinators. We found that, as expected, the B. ruderatus population was characterized by relatively low heterozygosity, number of alleles and colony density. Across all species, inbreeding was absent or present but weak (FIS  = 0.01-0.02). Using queen genotypes reconstructed from worker sibships and colony locations estimated from the positions of workers within these sibships, we found that significant isolation by distance was absent in B. lapidarius, B. hortorum and B. ruderatus. In B. terrestris and B. pascuorum, it was present but weak; for example, in these two species, expected relatedness of queens founding colonies 1 m apart was 0.02. These results show that bumble bee populations exhibit low levels of spatial genetic structure at fine spatial scales, most likely because of ongoing gene flow via widespread queen dispersal. In addition, the results demonstrate the potential for agri-environment scheme conservation measures to facilitate fine-scale gene flow by creating a more even distribution of suitable habitats across landscapes. PMID:24980963

  8. Fine-scale spatial genetic structure of common and declining bumble bees across an agricultural landscape

    PubMed Central

    Dreier, Stephanie; Redhead, John W; Warren, Ian A; Bourke, Andrew F G; Heard, Matthew S; Jordan, William C; Sumner, Seirian; Wang, Jinliang; Carvell, Claire

    2014-01-01

    Land-use changes have threatened populations of many insect pollinators, including bumble bees. Patterns of dispersal and gene flow are key determinants of species' ability to respond to land-use change, but have been little investigated at a fine scale (<10 km) in bumble bees. Using microsatellite markers, we determined the fine-scale spatial genetic structure of populations of four common Bombus species (B. terrestris, B. lapidarius, B. pascuorum and B. hortorum) and one declining species (B. ruderatus) in an agricultural landscape in Southern England, UK. The study landscape contained sown flower patches representing agri-environment options for pollinators. We found that, as expected, the B. ruderatus population was characterized by relatively low heterozygosity, number of alleles and colony density. Across all species, inbreeding was absent or present but weak (FIS = 0.01–0.02). Using queen genotypes reconstructed from worker sibships and colony locations estimated from the positions of workers within these sibships, we found that significant isolation by distance was absent in B. lapidarius, B. hortorum and B. ruderatus. In B. terrestris and B. pascuorum, it was present but weak; for example, in these two species, expected relatedness of queens founding colonies 1 m apart was 0.02. These results show that bumble bee populations exhibit low levels of spatial genetic structure at fine spatial scales, most likely because of ongoing gene flow via widespread queen dispersal. In addition, the results demonstrate the potential for agri-environment scheme conservation measures to facilitate fine-scale gene flow by creating a more even distribution of suitable habitats across landscapes. PMID:24980963

  9. Organic Farming Benefits Local Plant Diversity in Vineyard Farms Located in Intensive Agricultural Landscapes

    NASA Astrophysics Data System (ADS)

    Nascimbene, Juri; Marini, Lorenzo; Paoletti, Maurizio G.

    2012-05-01

    The majority of research on organic farming has considered arable and grassland farming systems in Central and Northern Europe, whilst only a few studies have been carried out in Mediterranean agro-systems, such as vineyards, despite their economic importance. The main aim of the study was to test whether organic farming enhances local plant species richness in both crop and non-crop areas of vineyard farms located in intensive conventional landscapes. Nine conventional and nine organic farms were selected in an intensively cultivated region (i.e. no gradient in landscape composition) in northern Italy. In each farm, vascular plants were sampled in one vineyard and in two non-crop linear habitats, grass strips and hedgerows, adjacent to vineyards and therefore potentially influenced by farming. We used linear mixed models to test the effect of farming, and species longevity (annual vs. perennial) separately for the three habitat types. In our intensive agricultural landscapes organic farming promoted local plant species richness in vineyard fields, and grassland strips while we found no effect for linear hedgerows. Differences in species richness were not associated to differences in species composition, indicating that similar plant communities were hosted in vineyard farms independently of the management type. This negative effect of conventional farming was probably due to the use of herbicides, while mechanical operations and mowing regime did not differ between organic and conventional farms. In grassland strips, and only marginally in vineyards, we found that the positive effect of organic farming was more pronounced for perennial than annual species.

  10. Energy budget components, ammonia concentration and flux measurements on an agricultural landscape near Bjerringbro, Denmark

    NASA Astrophysics Data System (ADS)

    Pogány, Andrea; Weidinger, Tamás.; Bienkowski, Jerzy; Bordás, Árpád.; Bozóki, Zoltán.; Eredics, Attila; Hensen, Arjan; Janku, Krzysztof; Kiss, Győző; Kraai, Aline; Istenes, Zoltán.; Mohácsi, Árpád.; Szabó, Gábor; Schelde, Kirsten; Theobald, Mark

    2010-05-01

    As a part of the NitroEurope common field experiment, energy budget components and ammonia concentrations were measured by various methods on an agricultural field near Bjerringbro, Denmark in April 2009. Several sources of ammonia (pig farms, nearby fertilized fields) were present in the landscape and the field itself was also fertilized with pig slurry during the campaign. Turbulent fluxes were calculated using micrometeorological measurement data (standard meteorological parameters, radiation and surface energy budget components) as well as three different methods: (i) the gradient, (ii) the Bowen ratio and (iii) the eddy covariance method using 15 min average time. Results obtained using different methodologies for flux calculations and local effects on energy budget closure were compared. Instrumentation used for measuring ammonia concentrations included two wet-chemical (AMANDA) instruments and two photoacoustic instruments (a mid-IR CO2 laser based Nitolux and a self-developed near-IR diode laser based WaSul instrument). The WaSul instrument was operated in gradient configuration, which also enables the calculation of ammonia fluxes. The instruments were placed at different points of the field to gain more information on the spatial concentration distribution. Ammonia concentration data measured by the different instruments and wind speed and direction data were used to estimate the location of ammonia sources within the landscape. After fertilization of the field ammonia emission fluxes were calculated from the gradient data.

  11. Landscape planning for agricultural nonpoint source pollution reduction III: Assessing phosphorus and sediment reduction potential

    USGS Publications Warehouse

    Diebel, M.W.; Maxted, J.T.; Robertson, D.M.; Han, S.; Vander Zanden, M. J.

    2009-01-01

    Riparian buffers have the potential to improve stream water quality in agricultural landscapes. This potential may vary in response to landscape characteristics such as soils, topography, land use, and human activities, including legacies of historical land management. We built a predictive model to estimate the sediment and phosphorus load reduction that should be achievable following the implementation of riparian buffers; then we estimated load reduction potential for a set of 1598 watersheds (average 54 km2) in Wisconsin. Our results indicate that land cover is generally the most important driver of constituent loads in Wisconsin streams, but its influence varies among pollutants and according to the scale at which it is measured. Physiographic (drainage density) variation also influenced sediment and phosphorus loads. The effect of historical land use on present-day channel erosion and variation in soil texture are the most important sources of phosphorus and sediment that riparian buffers cannot attenuate. However, in most watersheds, a large proportion (approximately 70%) of these pollutants can be eliminated from streams with buffers. Cumulative frequency distributions of load reduction potential indicate that targeting pollution reduction in the highest 10% of Wisconsin watersheds would reduce total phosphorus and sediment loads in the entire state by approximately 20%. These results support our approach of geographically targeting nonpoint source pollution reduction at multiple scales, including the watershed scale. ?? 2008 Springer Science+Business Media, LLC.

  12. Biodiversity and agriculture in dynamic landscapes: Integrating ground and remotely-sensed baseline surveys.

    PubMed

    Gillison, Andrew N; Asner, Gregory P; Fernandes, Erick C M; Mafalacusser, Jacinto; Banze, Aurélio; Izidine, Samira; da Fonseca, Ambrósio R; Pacate, Hermenegildo

    2016-07-15

    Sustainable biodiversity and land management require a cost-effective means of forecasting landscape response to environmental change. Conventional species-based, regional biodiversity assessments are rarely adequate for policy planning and decision making. We show how new ground and remotely-sensed survey methods can be coordinated to help elucidate and predict relationships between biodiversity, land use and soil properties along complex biophysical gradients that typify many similar landscapes worldwide. In the lower Zambezi valley, Mozambique we used environmental, gradient-directed transects (gradsects) to sample vascular plant species, plant functional types, vegetation structure, soil properties and land-use characteristics. Soil fertility indices were derived using novel multidimensional scaling of soil properties. To facilitate spatial analysis, we applied a probabilistic remote sensing approach, analyzing Landsat 7 satellite imagery to map photosynthetically active and inactive vegetation and bare soil along each gradsect. Despite the relatively low sample number, we found highly significant correlations between single and combined sets of specific plant, soil and remotely sensed variables that permitted testable spatial projections of biodiversity and soil fertility across the regional land-use mosaic. This integrative and rapid approach provides a low-cost, high-return and readily transferable methodology that permits the ready identification of testable biodiversity indicators for adaptive management of biodiversity and potential agricultural productivity. PMID:27064732

  13. Mitigating Nitrous Oxide Emissions from Agricultural Landscape: The Role of Isotopic Techniques

    NASA Astrophysics Data System (ADS)

    Zaman, Mohammad; Nguyen, Minh Long

    2014-05-01

    A review of studies from agricultural landscapes indicate that intensification of agricultural activities, inefficient use of reactive nitrogen (N) fertilizers and irrigation water, increasing human population and changes in their diet (more protein demand), high stocking rate (number of grazing livestock per hectare) and intensive cultivation are the major influencing factors for nitrous oxide (N2O) emissions into the atmosphere. Nitrification (both autotrophic and heterotrophic), denitrification and dissimilatory nitrate reduction to ammonium (DNRA) are the three major microbial processes that produce greenhouse N2O and non-greenhouse gas (N2) and can sometimes occur concurrently in a given soil system. The contribution of N2O production from each of these microbial processes is inconclusive because of the complex interactions between various microbial processes and the physical and chemical conditions in soil microsite (s). Nitrous oxide emissions across an agricultural landscape from different N inputs (chemical fertilizers and animal manure) and soil types are also extremely variable both temporally and spatially and range from 1-20% of the applied N and could therefore represent agronomic loss. The available conventional methods such as acetylene (C2H2) inhibition and helium (He) cannot accurately measure both N2O and N2 and their ratio in a given soil. The use of 15N stable isotopic technique offers the best option to measure both N2O and N2 and to identify their source (nitrification and denitrification) with a greater accuracy. Manipulating soil and fertilizer management practices can minimise these gaseous N losses. For example the combined use of urease inhibitor like (N-(n-butyl) thiophosphoric triamide (nBTPT) (trade name Agrotain®) and nitrification inhibitor dicyandiamide (DCD) with urea (100 kg N ha-1) or animal urine (600 kg N ha-1) was shown to reduce N losses by 39-53 % via denitrification-nitrification-DNRA processes. Other farm management

  14. Railway Embankments as New Habitat for Pollinators in an Agricultural Landscape

    PubMed Central

    Moroń, Dawid; Skórka, Piotr; Lenda, Magdalena; Rożej-Pabijan, Elżbieta; Wantuch, Marta; Kajzer-Bonk, Joanna; Celary, Waldemar; Mielczarek, Łukasz Emil; Tryjanowski, Piotr

    2014-01-01

    Pollinating insect populations, essential for maintaining wild plant diversity and agricultural productivity, rely on (semi)natural habitats. An increasing human population is encroaching upon and deteriorating pollinator habitats. Thus the population persistence of pollinating insects and their associated ecosystem services may depend upon on man-made novel habitats; however, their importance for ecosystem services is barely understood. We tested if man-made infrastructure (railway embankments) in an agricultural landscape establishes novel habitats that support large populations of pollinators (bees, butterflies, hoverflies) when compared to typical habitats for these insects, i.e., semi-natural grasslands. We also identified key environmental factors affecting the species richness and abundance of pollinators on embankments. Species richness and abundance of bees and butterflies were higher for railway embankments than for grasslands. The occurrence of bare (non-vegetated) ground on embankments positively affected bee species richness and abundance, but negatively affected butterfly populations. Species richness and abundance of butterflies positively depended on species richness of native plants on embankments, whereas bee species richness was positively affected by species richness of non-native flowering plants. The density of shrubs on embankments negatively affected the number of bee species and their abundance. Bee and hoverfly species richness were positively related to wood cover in a landscape surrounding embankments. This is the first study showing that railway embankments constitute valuable habitat for the conservation of pollinators in farmland. Specific conservation strategies involving embankments should focus on preventing habitat deterioration due to encroachment of dense shrubs and maintaining grassland vegetation with patches of bare ground. PMID:25054427

  15. Landscape conditions predisposing grizzly bears to conflicts on private agricultural lands in the western USA

    USGS Publications Warehouse

    Wilson, S.M.; Madel, M.J.; Mattson, D.J.; Graham, J.M.; Merrill, T.

    2006-01-01

    We used multiple logistic regression to model how different landscape conditions contributed to the probability of human-grizzly bear conflicts on private agricultural ranch lands. We used locations of livestock pastures, traditional livestock carcass disposal areas (boneyards), beehives, and wetland-riparian associated vegetation to model the locations of 178 reported human-grizzly bear conflicts along the Rocky Mountain East Front, Montana, USA during 1986-2001. We surveyed 61 livestock producers in the upper Teton watershed of north-central Montana, to collect spatial and temporal data on livestock pastures, boneyards, and beehives for the same period, accounting for changes in livestock and boneyard management and beehive location and protection, for each season. We used 2032 random points to represent the null hypothesis of random location relative to potential explanatory landscape features, and used Akaike's Information Criteria (AIC/AICC) and Hosmer-Lemeshow goodness-of-fit statistics for model selection. We used a resulting "best" model to map contours of predicted probabilities of conflict, and used this map for verification with an independent dataset of conflicts to provide additional insights regarding the nature of conflicts. The presence of riparian vegetation and distances to spring, summer, and fall sheep or cattle pastures, calving and sheep lambing areas, unmanaged boneyards, and fenced and unfenced beehives were all associated with the likelihood of human-grizzly bear conflicts. Our model suggests that collections of attractants concentrated in high quality bear habitat largely explain broad patterns of human-grizzly bear conflicts on private agricultural land in our study area. ?? 2005 Elsevier Ltd. All rights reserved.

  16. Impact of climate change on the water cycle of agricultural landscapes in Southwest Germany

    NASA Astrophysics Data System (ADS)

    Witte, Irene; Ingwersen, Joachim; Gayler, Sebastian; Streck, Thilo

    2016-04-01

    For agricultural production and life in general, water is a necessity. To ensure food and drinking water security in the future an understanding of the impact of climate change on the water cycle is indispensable. The objective of this PhD research is to assess how higher temperatures, higher atmospheric CO2 concentration and changing precipitation patterns will alter the water cycle of agricultural landscapes in Southwest Germany. As representative key characteristics data evaluation will focus on water use efficiency (WUE) and groundwater recharge. The main research question is whether the positive effect of elevated atmospheric CO2 on WUE will be overcompensated by a decrease in net primary production due to warming and to altered seasonal water availability caused by higher rainfall variability. Elevated atmospheric CO2 stimulates plant growth and improves WUE, whereas higher temperatures are expected to reduce net primary production and groundwater recharge. Another research question referring to groundwater recharge is whether groundwater recharge will increase in winter and decrease in summer in Southwest Germany. Changed groundwater recharge directly affects drinking water supply and is an indicator for possible temporary water shortages in agricultural production. A multi-model ensemble composed of 16 combinations of four crop growth models, two water regime models and two nitrogen models will be calibrated and validated against sets of field data. Field data will be provided by FOR 1965 from 2009-2015 for the Kraichgau region and the Swabian Alb, two contrasting areas with regard to climate and agricultural intensity. By using a multi model ensemble uncertainties in predictions due to different model structures (epistemic uncertainty) can be quantified. The uncertainty related to the randomness of inputs and parameters, the so-called aleatory uncertainty, will be additionally assessed for each of the 16 models. Hence, a more reliable range of future

  17. Nitrogen transport within an agricultural landscape: insights on how hydrology, biogeochemistry, and the landscape intersect to control the fate and transport of nitrogen in the Mississippi Delta

    USGS Publications Warehouse

    Barlow, Jeannie R.; Kröger, Robert

    2014-01-01

    Nitrogen (N) is a ubiquitous contaminant throughout agricultural landscapes due to both the application of inorganic and organic fertilizers to agricultural fields and the general persistence of nitrate (NO3 ) in oxygenated aqueous environments (Denver et al. 2010; Domagalski et al. 2008; Green et al. 2008; Coupe 2001; Nolan and Stoner 2000). In order to understand why excess N occurs various hydrologic systems (environments), it is important to consider potential sources, the locations of these sources in the watershed, and the timing of the application of sources with respect to the movement of water. To learn how to manage N in a watershed, it is necessary to identify and quantify flow paths and biogeochemical conditions, which ultimately combine to determine transport and fate. If sources, transport mechanisms, and biogeochemical controls were uniformly distributed, it would be possible to manage N uniformly throughout a watershed. However, uniform conditions are rare to nonexistent in the natural world and in the landscape altered for agricultural production. In order to adjust management activities on the landscape to have the greatest effect, it is important to understand the fate and transport N within the intersection of hydrology and biogeochemistry, that is, to understand the extent and duration of the hydrologic and biogeochemical controls as N is routed through and among each hydrologic compartment.

  18. Surface water and groundwater nitrogen dynamics in a well drained riparian forest within a poorly drainged agricultural landscape

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Riparian ecosystems, through their unique position in the agricultural landscape and ability to influence nutrient cycles, can potentially reduce nutrient loading to surface and ground waters. The primary purpose of this study was to determine the efficacy of a well-drained, mixed-deciduous riparia...

  19. Landscape fragmentation and pollinator movement within agricultural environments: a modelling framework for exploring foraging and movement ecology

    PubMed Central

    2014-01-01

    Pollinator decline has been linked to landscape change, through both habitat fragmentation and the loss of habitat suitable for the pollinators to live within. One method for exploring why landscape change should affect pollinator populations is to combine individual-level behavioural ecological techniques with larger-scale landscape ecology. A modelling framework is described that uses spatially-explicit individual-based models to explore the effects of individual behavioural rules within a landscape. The technique described gives a simple method for exploring the effects of the removal of wild corridors, and the creation of wild set-aside fields: interventions that are common to many national agricultural policies. The effects of these manipulations on central-place nesting pollinators are varied, and depend upon the behavioural rules that the pollinators are using to move through the environment. The value of this modelling framework is discussed, and future directions for exploration are identified. PMID:24795848

  20. Landscape context mediates influence of local food abundance on wetland use by wintering shorebirds in an agricultural valley

    USGS Publications Warehouse

    Taft, Oriane W.; Haig, Susan M.

    2006-01-01

    While it is widely understood that local abundance of benthic invertebrates can greatly influence the distribution and abundance of wetland birds, no studies have examined if wetland landscape context can mediate this relationship. We studied the influence of wetland food abundance and landscape context on use of agricultural wetlands by wintering dunlin (Calidris alpina) and killdeer (Charadrius vociferus) in the Willamette Valley of Oregon, USA, over two winters (1999a??2000, 2000a??2001) of differing rainfall and subsequent habitat distribution. We monitored bird use (frequency of occurrence and abundance) at a sample of wetlands differing in local food abundance (density and biomass) and landscape context [adjacent shorebird habitat (defined as ha of wet habitat with less than 50% vegetative cover and within a 2-km radius) and nearest neighbor distance]. We evaluated predictive models for bird use using linear regression and the Cp criterion to select the most parsimonious model. During the dry winter (2000a??2001), dunlin exhibited greater use of sites with higher invertebrate density and biomass but also with more adjacent shorebird habitat and closest to a wetland neighbor. However, neither landscape context nor food abundance were important predictors of dunlin use during the wet winter (1999a??2000). Use of sites by killdeer was unrelated to either local food abundance or landscape context measures during both winters. Our findings contribute to a growing recognition of the importance of landscape structure to wetland birds and highlight a number of implications for the spatial planning and enhancement of wetlands using a landscape approach.

  1. Vegetation water content mapping in a diverse agricultural landscape: National Airborne Field Experiment 2006

    NASA Astrophysics Data System (ADS)

    Cosh, Michael H.; Tao, Jing; Jackson, Thomas J.; McKee, Lynn; O'Neill, Peggy

    2010-05-01

    Mapping land cover and vegetation characteristics on a regional scale is critical to soil moisture retrieval using microwave remote sensing. In aircraft-based experiments such as the National Airborne Field Experiment 2006 (NAFE'06), it is challenging to provide accurate high resolution vegetation information, especially on a daily basis. A technique proposed in previous studies was adapted here to the heterogenous conditions encountered in NAFE'06, which included a hydrologically complex landscape consisting of both irrigated and dryland agriculture. Using field vegetation sampling and ground-based reflectance measurements, the knowledge base for relating the Normalized Difference Water Index (NDWI) and the vegetation water content was extended to a greater diversity of agricultural crops, which included dryland and irrigated wheat, alfalfa, and canola. Critical to the generation of vegetation water content maps, the land cover for this region was determined from satellite visible/infrared imagery and ground surveys with an accuracy of 95.5% and a kappa coefficient of 0.95. The vegetation water content was estimated with a root mean square error of 0.33 kg/m2. The results of this investigation contribute to a more robust database of global vegetation water content observations and demonstrate that the approach can be applied with high accuracy.

  2. Tightly-Coupled Plant-Soil Nitrogen Cycling: Comparison of Organic Farms across an Agricultural Landscape.

    PubMed

    Bowles, Timothy M; Hollander, Allan D; Steenwerth, Kerri; Jackson, Louise E

    2015-01-01

    How farming systems supply sufficient nitrogen (N) for high yields but with reduced N losses is a central challenge for reducing the tradeoffs often associated with N cycling in agriculture. Variability in soil organic matter and management of organic farms across an agricultural landscape may yield insights for improving N cycling and for evaluating novel indicators of N availability. We assessed yields, plant-soil N cycling, and root expression of N metabolism genes across a representative set of organic fields growing Roma-type tomatoes (Solanum lycopersicum L.) in an intensively-managed agricultural landscape in California, USA. The fields spanned a three-fold range of soil carbon (C) and N but had similar soil types, texture, and pH. Organic tomato yields ranged from 22.9 to 120.1 Mg ha-1 with a mean similar to the county average (86.1 Mg ha-1), which included mostly conventionally-grown tomatoes. Substantial variability in soil inorganic N concentrations, tomato N, and root gene expression indicated a range of possible tradeoffs between yields and potential for N losses across the fields. Fields showing evidence of tightly-coupled plant-soil N cycling, a desirable scenario in which high crop yields are supported by adequate N availability but low potential for N loss, had the highest total and labile soil C and N and received organic matter inputs with a range of N availability. In these fields, elevated expression of a key gene involved in root N assimilation, cytosolic glutamine synthetase GS1, confirmed that plant N assimilation was high even when inorganic N pools were low. Thus tightly-coupled N cycling occurred on several working organic farms. Novel combinations of N cycling indicators (i.e. inorganic N along with soil microbial activity and root gene expression for N assimilation) would support adaptive management for improved N cycling on organic as well as conventional farms, especially when plant-soil N cycling is rapid. PMID:26121264

  3. Tightly-Coupled Plant-Soil Nitrogen Cycling: Comparison of Organic Farms across an Agricultural Landscape

    PubMed Central

    Bowles, Timothy M.; Hollander, Allan D.; Steenwerth, Kerri; Jackson, Louise E.

    2015-01-01

    How farming systems supply sufficient nitrogen (N) for high yields but with reduced N losses is a central challenge for reducing the tradeoffs often associated with N cycling in agriculture. Variability in soil organic matter and management of organic farms across an agricultural landscape may yield insights for improving N cycling and for evaluating novel indicators of N availability. We assessed yields, plant-soil N cycling, and root expression of N metabolism genes across a representative set of organic fields growing Roma-type tomatoes (Solanum lycopersicum L.) in an intensively-managed agricultural landscape in California, USA. The fields spanned a three-fold range of soil carbon (C) and N but had similar soil types, texture, and pH. Organic tomato yields ranged from 22.9 to 120.1 Mg ha-1 with a mean similar to the county average (86.1 Mg ha-1), which included mostly conventionally-grown tomatoes. Substantial variability in soil inorganic N concentrations, tomato N, and root gene expression indicated a range of possible tradeoffs between yields and potential for N losses across the fields. Fields showing evidence of tightly-coupled plant-soil N cycling, a desirable scenario in which high crop yields are supported by adequate N availability but low potential for N loss, had the highest total and labile soil C and N and received organic matter inputs with a range of N availability. In these fields, elevated expression of a key gene involved in root N assimilation, cytosolic glutamine synthetase GS1, confirmed that plant N assimilation was high even when inorganic N pools were low. Thus tightly-coupled N cycling occurred on several working organic farms. Novel combinations of N cycling indicators (i.e. inorganic N along with soil microbial activity and root gene expression for N assimilation) would support adaptive management for improved N cycling on organic as well as conventional farms, especially when plant-soil N cycling is rapid. PMID:26121264

  4. Nitrous oxide emissions from agricultural landscapes: quantification tools, policy development, and opportunities for improved management

    NASA Astrophysics Data System (ADS)

    Tonitto, C.; Gurwick, N. P.

    2012-12-01

    Policy initiatives to reduce greenhouse gas emissions (GHG) have promoted the development of agricultural management protocols to increase SOC storage and reduce GHG emissions. We review approaches for quantifying N2O flux from agricultural landscapes. We summarize the temporal and spatial extent of observations across representative soil classes, climate zones, cropping systems, and management scenarios. We review applications of simulation and empirical modeling approaches and compare validation outcomes across modeling tools. Subsequently, we review current model application in agricultural management protocols. In particular, we compare approaches adapted for compliance with the California Global Warming Solutions Act, the Alberta Climate Change and Emissions Management Act, and by the American Carbon Registry. In the absence of regional data to drive model development, policies that require GHG quantification often use simple empirical models based on highly aggregated data of N2O flux as a function of applied N - Tier 1 models according to IPCC categorization. As participants in development of protocols that could be used in carbon offset markets, we observed that stakeholders outside of the biogeochemistry community favored outcomes from simulation modeling (Tier 3) rather than empirical modeling (Tier 2). In contrast, scientific advisors were more accepting of outcomes based on statistical approaches that rely on local observations, and their views sometimes swayed policy practitioners over the course of policy development. Both Tier 2 and Tier 3 approaches have been implemented in current policy development, and it is important that the strengths and limitations of both approaches, in the face of available data, be well-understood by those drafting and adopting policies and protocols. The reliability of all models is contingent on sufficient observations for model development and validation. Simulation models applied without site-calibration generally

  5. Silicate weathering and CO2 consumption within agricultural landscapes, the Ohio-Tennessee River Basin, USA

    NASA Astrophysics Data System (ADS)

    Fortner, S. K.; Lyons, W. B.; Carey, A. E.; Shipitalo, M. J.; Welch, S. A.; Welch, K. A.

    2012-03-01

    Myriad studies have shown the extent of human alteration to global biogeochemical cycles. Yet, there is only a limited understanding of the influence that humans have over silicate weathering fluxes; fluxes that have regulated atmospheric carbon dioxide concentrations and global climate over geologic timescales. Natural landscapes have been reshaped into agricultural ones to meet food needs for growing world populations. These processes modify soil properties, alter hydrology, affect erosion, and consequently impact water-soil-rock interactions such as chemical weathering. Dissolved silica (DSi), Ca2+, Mg2+, NO3-, and total alkalinity were measured in water samples collected from five small (0.0065 to 0.383 km2) gauged watersheds at the North Appalachian Experimental Watershed (NAEW) near Coshocton, Ohio, USA. The sampled watersheds in this unglaciated region include: a forested site (70+ year stand), mixed agricultural use (corn, forest, pasture), an unimproved pasture, tilled corn, and a recently (<3 yr) converted no-till corn field. The first three watersheds had perennial streams, but the two corn watersheds only produced runoff during storms and snowmelt. For the perennial streams, total discharge was an important control of dissolved silicate transport. Median DSi yields (2210-3080 kg km-2 yr-1) were similar to the median of annual averages between 1979-2009 for the much larger Ohio-Tennessee River Basin (2560 kg km-2 yr-1). Corn watersheds, which only had surface runoff, had substantially lower DSi yields (<530 kg km-2 yr-1) than the perennial-flow watersheds. The lack of contributions from Si-enriched groundwater largely explained their much lower DSi yields with respect to sites having baseflow. A significant positive correlation between the molar ratio of (Ca2++Mg2+)/alkalinity to DSi in the tilled corn and the forested site suggested, however, that silicate minerals weathered as alkalinity was lost via enhanced nitrification resulting from fertilizer

  6. Model analysis of riparian buffer effectiveness for reducing nutrient inputs to streams in agricultural landscapes

    NASA Astrophysics Data System (ADS)

    McKane, R. B.; M, S.; F, P.; Kwiatkowski, B. L.; Rastetter, E. B.

    2006-12-01

    Federal and state agencies responsible for protecting water quality rely mainly on statistically-based methods to assess and manage risks to the nation's streams, lakes and estuaries. Although statistical approaches provide valuable information on current trends in water quality, process-based simulation models are essential for understanding and forecasting how changes in human activities across complex landscapes impact the transport of nutrients and contaminants to surface waters. To address this need, we developed a broadly applicable, process-based watershed simulator that links a spatially-explicit hydrologic model and a terrestrial biogeochemistry model (MEL). See Stieglitz et al. and Pan et al., this meeting, for details on the design and verification of this simulator. Here we apply the watershed simulator to a generalized agricultural setting to demonstrate its potential for informing policy and management decisions concerning water quality. This demonstration specifically explores the effectiveness of riparian buffers for reducing the transport of nitrogenous fertilizers from agricultural fields to streams. The interaction of hydrologic and biogeochemical processes represented in our simulator allows several important questions to be addressed. (1) For a range of upland fertilization rates, to what extent do riparian buffers reduce nitrogen inputs to streams? (2) How does buffer effectiveness change over time as the plant-soil system approaches N-saturation? (3) How can buffers be managed to increase their effectiveness, e.g., through periodic harvest and replanting? The model results illustrate that, while the answers to these questions depend to some extent on site factors (climatic regime, soil properties and vegetation type), in all cases riparian buffers have a limited capacity to reduce nitrogen inputs to streams where fertilization rates approach those typically used for intensive agriculture (e.g., 200 kg N per ha per year for corn in the U

  7. [Impacts of landscape patterns on heavy metal contamination of agricultural top soils in the Pearl River Delta, South China].

    PubMed

    Li, Cheng; Li, Fang-bai; Wu, Zhi-feng; Cheng, Jiong

    2015-04-01

    Landscape patterns are known to influence many ecological processes, but the relationship between landscape patterns and soil pollution processes is not well understood. Based on 300 top soil samples, land use and cover map for the Pearl River Delta (PRD) of 2005, this study explored the characteristics and spatial pattern of heavy metal contamination of agricultural top soils and examined the impacts of landscape patterns on the heavy metal contamination in the buffers of soil samples. Research methods included geostatistical analysis, landscape pattern analysis, single-factor pollution indices, and Pearson correlation analysis. We found that: 1) out of the 235 agricultural soil samples, 3.8%, 0.4%, 17.0% and 9.4% samples exceeded the Grade II national standard for As, Pb, Cd and Ni concentrations respectively. High pollution levels were found in three cities, Guangzhou, Foshan and Zhongshan; 2) soils in the farmland were more polluted than those in the forest and orchard land, and there were no differences among different agricultural land use types in contamination level of each heavy metal (except Cd); and 3) the proportion, mean patch area as well as the degree of landscape fragmentation, landscape-level structural complexity and aggregation/connectivity of water at the buffer zone were significantly positively correlated with the contamination level of each of the four heavy metals in agricultural top soils. Part of the landscape pattern of urban land in the buffer zone also positively correlated with Pb and Cd levels (P < 0.05). On the contrary, the proportion, mean patch area and aggregation degree of forest land negatively correlated with soil Pb and Ni levels (P < 0.05); and 4) the closer to the industry land were the soil samples, the more polluted the soils were for Pb, Cd and Ni. Only landscape diversity was found to be positively correlated with soil Cd contamination. The study results provide new information and scientific basis for heavy metal

  8. Wide-area mapping of small-scale features in agricultural landscapes using airborne remote sensing

    PubMed Central

    O’Connell, Jerome; Bradter, Ute; Benton, Tim G.

    2015-01-01

    Natural and semi-natural habitats in agricultural landscapes are likely to come under increasing pressure with the global population set to exceed 9 billion by 2050. These non-cropped habitats are primarily made up of trees, hedgerows and grassy margins and their amount, quality and spatial configuration can have strong implications for the delivery and sustainability of various ecosystem services. In this study high spatial resolution (0.5 m) colour infrared aerial photography (CIR) was used in object based image analysis for the classification of non-cropped habitat in a 10,029 ha area of southeast England. Three classification scenarios were devised using 4 and 9 class scenarios. The machine learning algorithm Random Forest (RF) was used to reduce the number of variables used for each classification scenario by 25.5 % ± 2.7%. Proportion of votes from the 4 class hierarchy was made available to the 9 class scenarios and where the highest ranked variables in all cases. This approach allowed for misclassified parent objects to be correctly classified at a lower level. A single object hierarchy with 4 class proportion of votes produced the best result (kappa 0.909). Validation of the optimum training sample size in RF showed no significant difference between mean internal out-of-bag error and external validation. As an example of the utility of this data, we assessed habitat suitability for a declining farmland bird, the yellowhammer (Emberiza citronella), which requires hedgerows associated with grassy margins. We found that ∼22% of hedgerows were within 200 m of margins with an area >183.31 m2. The results from this analysis can form a key information source at the environmental and policy level in landscape optimisation for food production and ecosystem service sustainability. PMID:26664131

  9. Wide-area mapping of small-scale features in agricultural landscapes using airborne remote sensing

    NASA Astrophysics Data System (ADS)

    O'Connell, Jerome; Bradter, Ute; Benton, Tim G.

    2015-11-01

    Natural and semi-natural habitats in agricultural landscapes are likely to come under increasing pressure with the global population set to exceed 9 billion by 2050. These non-cropped habitats are primarily made up of trees, hedgerows and grassy margins and their amount, quality and spatial configuration can have strong implications for the delivery and sustainability of various ecosystem services. In this study high spatial resolution (0.5 m) colour infrared aerial photography (CIR) was used in object based image analysis for the classification of non-cropped habitat in a 10,029 ha area of southeast England. Three classification scenarios were devised using 4 and 9 class scenarios. The machine learning algorithm Random Forest (RF) was used to reduce the number of variables used for each classification scenario by 25.5 % ± 2.7%. Proportion of votes from the 4 class hierarchy was made available to the 9 class scenarios and where the highest ranked variables in all cases. This approach allowed for misclassified parent objects to be correctly classified at a lower level. A single object hierarchy with 4 class proportion of votes produced the best result (kappa 0.909). Validation of the optimum training sample size in RF showed no significant difference between mean internal out-of-bag error and external validation. As an example of the utility of this data, we assessed habitat suitability for a declining farmland bird, the yellowhammer (Emberiza citronella), which requires hedgerows associated with grassy margins. We found that ∼22% of hedgerows were within 200 m of margins with an area >183.31 m2. The results from this analysis can form a key information source at the environmental and policy level in landscape optimisation for food production and ecosystem service sustainability.

  10. Biodiversity in Organic Farmland - How Does Landscape Context Influence Species Diversity in Organic Vs. Conventional Agricultural Fields?

    NASA Astrophysics Data System (ADS)

    Seufert, V.; Wood, S.; Reid, A.; Gonzalez, A.; Rhemtulla, J.; Ramankutty, N.

    2014-12-01

    The most important current driver of biodiversity loss is the conversion of natural habitats for human land uses, mostly for the purpose of food production. However, by causing this biodiversity loss, food production is eroding the very same ecosystem services (e.g. pollination and soil fertility) that it depends on. We therefore need to adopt more wildlife-friendly agricultural practices that can contribute to preserving biodiversity. Organic farming has been shown to typically host higher biodiversity than conventional farming. But how is the biodiversity benefit of organic management dependent on the landscape context farms are situated in? To implement organic farming as an effective means for protecting biodiversity and enhancing ecosystem services we need to understand better under what conditions organic management is most beneficial for species. We conducted a meta-analysis of the literature to answer this question, compiling the most comprehensive database to date of studies that monitored biodiversity in organic vs. conventional fields. We also collected information about the landscape surrounding these fields from remote sensing products. Our database consists of 348 study sites across North America and Europe. Our analysis shows that organic management can improve biodiversity in agricultural fields substantially. It is especially effective at preserving biodiversity in homogeneous landscapes that are structurally simplified and dominated by either cropland or pasture. In heterogeneous landscapes conventional agriculture might instead already hold high biodiversity, and organic management does not appear to provide as much of a benefit for species richness as in simplified landscapes. Our results suggest that strategies to maintain biodiversity-dependent ecosystem services should include a combination of pristine natural habitats, wildlife-friendly farming systems like organic farming, and high-yielding conventional systems, interspersed in structurally

  11. Temporal Beta Diversity of Bird Assemblages in Agricultural Landscapes: Land Cover Change vs. Stochastic Processes

    PubMed Central

    Baselga, Andrés; Bonthoux, Sébastien; Balent, Gérard

    2015-01-01

    Temporal variation in the composition of species assemblages could be the result of deterministic processes driven by environmental change and/or stochastic processes of colonization and local extinction. Here, we analyzed the relative roles of deterministic and stochastic processes on bird assemblages in an agricultural landscape of southwestern France. We first assessed the impact of land cover change that occurred between 1982 and 2007 on (i) the species composition (presence/absence) of bird assemblages and (ii) the spatial pattern of taxonomic beta diversity. We also compared the observed temporal change of bird assemblages with a null model accounting for the effect of stochastic dynamics on temporal beta diversity. Temporal assemblage dissimilarity was partitioned into two separate components, accounting for the replacement of species (i.e. turnover) and for the nested species losses (or gains) from one time to the other (i.e. nestedness-resultant dissimilarity), respectively. Neither the turnover nor the nestedness-resultant components of temporal variation were accurately explained by any of the measured variables accounting for land cover change (r2<0.06 in all cases). Additionally, the amount of spatial assemblage heterogeneity in the region did not significantly change between 1982 and 2007, and site-specific observed temporal dissimilarities were larger than null expectations in only 1% of sites for temporal turnover and 13% of sites for nestedness-resultant dissimilarity. Taken together, our results suggest that land cover change in this agricultural landscape had little impact on temporal beta diversity of bird assemblages. Although other unmeasured deterministic process could be driving the observed patterns, it is also possible that the observed changes in presence/absence species composition of local bird assemblages might be the consequence of stochastic processes in which species populations appeared and disappeared from specific localities in a

  12. Factors affecting songbird nest survival in riparian forests in a Midwestern agricultural landscape

    USGS Publications Warehouse

    Peak, R.G.; Thompson, F. R., III; Shaffer, T.L.

    2004-01-01

    We investigated factors affecting nest success of songbirds in riparian forest and buffers in northeastern Missouri. We used an information-theoretic approach to determine support for hypotheses concerning effects of nest-site, habitat-patch, edge, and temporal factors on nest success of songbirds in three narrow (55DS95 m) and three wide (400DS530 m) riparian forests with adjacent grasslandDSshrub buffer strips and in three narrow and three wide riparian forests without adjacent grasslandDSshrub buffer strips. We predicted that temporal effects would have the most support and that habitat-patch and edge effects would have little support, because nest predation would be great across all sites in the highly fragmented, predominantly agricultural landscape. Interval nest success was 0.404, 0.227, 0.070, and 0.186, respectively, for Gray Catbird (Dumetella carolinensis), Northern Cardinal (Cardinalis cardinalis), Indigo Bunting (Passerina cyanea), and forest interior species pooled (Acadian Flycatcher [Empidonax virescens], Wood Thrush [Hylocichla mustelina], Ovenbird [Seiurus aurocapillus], and Kentucky Warbler [Oporornis formosus]). The effect of nest stage on nest success had the most support; daily nest success for Gray Catbird and Indigo Bunting were lowest in the laying stage. We found strong support for greater nest success of Gray Catbird in riparian forests with adjacent buffer strips than in riparian forests without adjacent buffer strips. Patch width also occurred in the most supported model for Gray Catbird, but with very limited support. The null model received the most support for Northern Cardinal. Riparian forests provided breeding habitat for areas sensitive forest species and grassland-shrub nesting species. Buffer strips provided additional breeding habitat for grassland-shrub nesting species. Interval nest success for Indigo Bunting and area-sensitive forest species pooled, however, fell well below the level that is likely necessary to balance

  13. Factors affecting songbird nest survival in riparian forests in a midwestern agricultural landscape

    USGS Publications Warehouse

    Peak, R.G.; Thompson, F. R., III; Shaffer, T.L.

    2004-01-01

    We investigated factors affecting nest success of songbirds in riparian forest and buffers in northeastern Missouri. We used an information-theoretic approach to determine support for hypotheses concerning effects of nest-site, habitat-patch, edge, and temporal factors on nest success of songbirds in three narrow (55-95 m) and three wide (400-530 m) riparian forests with adjacent grassland-shrub buffer strips and in three narrow and three wide riparian forests without adjacent grassland-shrub buffer strips. We predicted that temporal effects would have the most support and that habitat-patch and edge effects would have little support, because nest predation would be great across all sites in the highly fragmented, predominantly agricultural landscape. Interval nest success was 0.404, 0.227, 0.070, and 0.186, respectively, for Gray Catbird (Dumetella carolinensis), Northern Cardinal (Cardinalis cardinalis), Indigo Bunting (Passerina cyanea), and forest interior species pooled (Acadian Flycatcher [Empidonax virescens], Wood Thrush [Hylocichla mustelina], Ovenbird [Seiurus aurocapillus], and Kentucky Warbler [Oporornis formosus]). The effect of nest stage on nest success had the most support; daily nest success for Gray Catbird and Indigo Bunting were lowest in the laying stage. We found strong support for greater nest success of Gray Catbird in riparian forests with adjacent buffer strips than in riparian forests without adjacent buffer strips. Patch width also occurred in the most-supported model for Gray Catbird, but with very limited support. The null model received the most support for Northern Cardinal. Riparian forests provided breeding habitat for area-sensitive forest species and grassland-shrub nesting species. Buffer strips provided additional breeding habitat for grassland-shrub nesting species. Interval nest success for Indigo Bunting and area-sensitive forest species pooled, however, fell well below the level that is likely necessary to balance juvenile

  14. The fate of soil organic carbon upon erosion, transport and deposition in agricultural landscapes - A review of different concepts

    NASA Astrophysics Data System (ADS)

    Kirkels, F. M. S. A.; Cammeraat, L. H.; Kuhn, N. J.

    2014-12-01

    Erosion and deposition redistribute large quantities of sediment and soil organic carbon (SOC) in agricultural landscapes. In the perspective of global carbon cycling, the coupling between erosion processes and the fate of SOC is of particular interest. However, different concepts have been proposed to assess the impact of erosion-induced lateral and vertical carbon fluxes. On landscape scale, this resulted in contrasting conclusions if agricultural soils represent either a carbon sink or source. The large global area of arable soil and generally high erosion rates, make these insights important. In this review, we aim to give an overview of the different conceptual relations described governing C dynamics at sites of erosion, along the transport pathway and at depositional sites and the current state of knowledge on the fate of SOC upon erosion, transport and deposition in agricultural landscapes. The impact of erosion on SOC dynamics differs for sites of erosion, deposition and during transport, with further influences by agricultural practices (e.g. tillage and fertilisation). Controlling processes are the detachment of sediment and SOC, net primary production resulting in dynamic replacement and changes in mineralisation upon transport and deposition due to aggregate breakdown and deep burial, respectively. However, the exact magnitude and dominance of these processes are debated, resulting in a controversy whether arable land functions as a sink or source for atmospheric CO2. Global estimations range between a net sink strength of 0.06-1 versus a source of 0.27-1.14 Gt C yr- 1 for agricultural soils. An eco-geomorphologic approach, which encompasses physical- and biological-driven factors (e.g. spatio-temporal variation in biological, geomorphological and biological processes, environmental conditions, mineralisation, and net primary production) is of importance to balance the carbon budget and ascertain sink or source formation at landscape scale. High spatio

  15. Nitrous oxide emissions and denitrification rates: A blueprint for smart management and remediation of agricultural landscapes.

    NASA Astrophysics Data System (ADS)

    Tomasek, A.; Hondzo, M.; Kozarek, J. L.

    2015-12-01

    resulting in the release of nitrous oxide, a greenhouse gas with 300 times the warming potential of carbon dioxide. The investigation of nitrous oxide emissions and correlation to denitrification rates will facilitate smart management and remediation efforts of agricultural landscapes.

  16. A survey of insect assemblages responding to volatiles from a ubiquitous fungus in an agricultural landscape.

    PubMed

    Davis, Thomas Seth; Landolt, Peter J

    2013-07-01

    We report here a first survey of insect orientation to fungal cultures and fungal volatiles from a community ecology perspective. We tested whether volatiles from a ubiquitous yeast-like fungus (Aureobasidium pullulans) are broadly attractive to insects in an agricultural landscape. We evaluated insect attraction to fungal cultures and synthetic compounds identified in fungal headspace (2-methyl-1-butanol, 3-methyl-1-butanol, 2-phenylethanol) in a spearmint (Mentha spicata L.) plantation. Three findings emerged: (1) 1,315 insects representing seven orders and 39 species oriented to traps, but 65 % of trapped insects were Dipterans, of which 80 % were hoverflies (Diptera: Syrphidae); (2) traps baited with A. pullulans caught 481 % more insects than unbaited control traps on average, and contained more diverse (Shannon's H index) and species rich assemblages than control traps, traps baited with Penicillium expansum, or uninoculated media; and (3) insects oriented in greatest abundance to a 1:1:1 blend of A. pullulans volatiles, but mean diversity scores were highest for traps baited with only 2-phenylethanol or 2-methyl-1-butanol. Our results show that individual components of fungal headspace are not equivalent in terms of the abundance and diversity of insects that orient to them. The low abundance of insects captured with P. expansum suggests that insect assemblages do not haphazardly orient to fungal volatiles. We conclude that volatiles from a common fungal species (A. pullulans) are attractive to a variety of insect taxa in an agricultural system, and that insect orientation to fungal volatiles may be a common ecological phenomenon. PMID:23564294

  17. The Network Of Shelterbelts As An Agroforestry System Controlling The Water Resources And Biodiversity In The Agricultural Landscape

    NASA Astrophysics Data System (ADS)

    Kędziora, Andrzej

    2015-01-01

    Long-term human activity has led to many unfavourable changes in landscape structure. The main negative effect has been a simplification of landscape structure reflecting the removal of stable ecosystems, such as forests, shelterbelts, strips of meadows and so on, which were converted into unstable ecosystems, mainly farmlands. Thanks to these changes, serious threats have been posed to the sustainable development of rural areas. The most hazardous of these involve a deteriorating of water balance, increased surface and ground water pollution, and impoverishment of biodiversity. An agroforestry system can serve as a toolkit which allows counteracting such negative changes in the landscape. This paper presents the main findings emerge from long-term investigations on the above issues carried out by the Institute for the Agricultural and Forest Environment of the Polish Academy of Sciences.

  18. Applying an agent-based model of agricultural terraces coupled with a landscape evolution model to explore the impact of human decision-making on terraced terrain

    NASA Astrophysics Data System (ADS)

    Glaubius, Jennifer

    2016-04-01

    Agricultural terraces impact landscape evolution as a result of long-term human-landscape interactions, including decisions regarding terrace maintenance and abandonment. Modeling simulations are often employed to examine the sensitivity of landscapes to various factors, such as rainfall and land cover. Landscape evolution models, erosion models, and hydrological models have all previously been used to simulate the impact of agricultural terrace construction on terrain evolution, soil erosion, and hydrological connectivity. Human choices regarding individual terraces have not been included in these models to this point, despite recent recognition that maintenance and abandonment decisions alter transport and storage patterns of soil and water in terraced terrain. An agent-based model of human decisions related to agricultural terraces is implemented based on a conceptual model of agricultural terrace life cycle stages created from a literature review of terracing impacts. The agricultural terracing agent-based model is then coupled with a landscape evolution model to explore the role of human decisions in the evolution of terraced landscapes. To fully explore this type of co-evolved landscape, human decision-making and its feedbacks must be included in landscape evolution models. Project results may also have implications for management of terraced terrain based on how human choices in these environments affect soil loss and land degradation.

  19. The change of nature and the nature of change in agricultural landscapes: Hydrologic regime shifts modulate ecological transitions

    NASA Astrophysics Data System (ADS)

    Foufoula-Georgiou, Efi; Takbiri, Zeinab; Czuba, Jonathan A.; Schwenk, Jon

    2015-08-01

    Hydrology in many agricultural landscapes around the world is changing in unprecedented ways due to the development of extensive surface and subsurface drainage systems that optimize productivity. This plumbing of the landscape alters water pathways, timings, and storage, creating new regimes of hydrologic response and driving a chain of environmental changes in sediment dynamics, nutrient cycling, and river ecology. In this work, we nonparametrically quantify the nature of hydrologic change in the Minnesota River Basin, an intensively managed agricultural landscape, and study how this change might modulate ecological transitions. During the growing season when climate effects are shown to be minimal, daily streamflow hydrographs exhibit sharper rising limbs and stronger dependence on the previous-day precipitation. We also find a changed storage-discharge relationship and show that the artificial landscape connectivity has most drastically affected the rainfall-runoff relationship at intermediate quantiles. Considering the whole year, we show that the combined climate and land use change effects reduce the inherent nonlinearity in the dynamics of daily streamflow, perhaps reflecting a more linearized engineered hydrologic system. Using a simplified dynamic interaction model that couples hydrology to river ecology, we demonstrate how the observed hydrologic change and/or the discharge-driven sediment generation dynamics may have modulated a regime shift in river ecology, namely extirpation of native mussel populations. We posit that such nonparametric analyses and reduced complexity modeling can provide more insight than highly parameterized models and can guide development of vulnerability assessments and integrated watershed management frameworks.

  20. Characterisation and change detection of the agricultural terraced landscape of Costa Viola (Calabria, Italy) in view of its sustainable management

    NASA Astrophysics Data System (ADS)

    Modica, Giuseppe; Praticò, Salvatore; Lanucara, Simone; Di Fazio, Salvatore

    2015-04-01

    The research presented in this paper aimed at the dynamic characterisation of the historical terraced landscape of 'Costa Viola', a coastal region in South Italy, in view of its sustainable management. Here the agricultural terraces, used for vineyards, over time have occupied very steep sites and today are recognised as worthy of protection because of their high cultural and scenic value. During the last century, because of the loss of economic competitiveness, the agricultural terraces have undergone progressive abandonment, followed by landscape deterioration and increase of hydrogeologic risk. As a consequence it has recently emerged the need to support the permanence of terraced agriculture through a sensitive management of the area, based on a precise and updated knowledge of the landscape system and its ongoing dynamics of change. To this end the main characteristics of the Costa Viola dry-stone terraces and the Land Use/Land Cover (LU/LC) evolution between 1955 and 2012 were analysed. Taking into consideration the very steep slopes of Costa Viola and the need to analyse with high precision the historical evolution of the terraced landscape, they were implemented investigation methods coupling the use of precision tools with in-situ detailed surveys. A parallel diachronic study was also carried out, covering nearly 60 years and aiming to identify the local geomorphological processes and forms (such as landslides) through stereoscopic analysis of high resolution historic aerial photograms (1955 and 1976) compared to full colour digital orthophotos (1988, 2006, 2008, 2012), direct on-field verification, analysis of cadastral data and pluviometric data series. The geomorphological processes were analysed also in relation with the changes occurred over time in the agricultural terraces and in the urban/rural interface evolution. They were implemented a geographic database based on PostGIS and a Spatial Data Infrastructure (SDI) developed in a GFOSS (Geographic

  1. How agricultural landscape features control the transfer of nutrient and eutrophication risk in headwater catchments?

    NASA Astrophysics Data System (ADS)

    Dupas, Rémi; Delmas, Magalie; Dorioz, Jean-Marcel; Garnier, Josette; Moatar, Florentina; Gascuel-Odoux, Chantal

    2014-05-01

    The degradation of surface water quality due to nitrogen and phosphorus pollution is a major concern for drinking water quality and ecosystems health. Numerous studies have demonstrated that headwater catchments are large contributors of nutrient loads to downstream waters bodies. In terms of scientific understanding of the processes controlling nutrient transfers, headwater catchments are relevant spatial units to study the role of landscape features because of the relatively low contribution of point sources and in-stream processes compared to larger river networks. This paper presents an analysis of the variability in space and time of observed N and P loads for a dataset of 160 headwater catchments at a national level (France). A multivariate statistical analysis was performed to relate observed N and P loads to spatial attributes describing agricultural landscapes and the physical characteristics of the catchments: climate, topography, soils, etc. We identified factors controlling N and P loads and N:P:Si ratios in freshwaters; and specifically spatially described factors, by considering river corridors and interaction between soils and land use attributes. The same catchment dataset is used to calibrate the Nutting model, i.e. a statistical model developed to estimate nutrient emission to surface water, using readily available data in France (Dupas et al., 2013). Nutting is a statistical model linking N/P sources and catchment land and river attributes to estimate mean interannual nitrate-N, total-N, dissolved-P and total-P loads. It allows to extrapolate nutrient loads in unmonitored catchments at a national level and to estimate the risk of eutrophication in freshwaters considering Redfield's (1963) N:P:Si ratios. Results show that N is in excess over silica in 93% of French headwater bodies, and that phosphorus is in excess over silica in 26%-65% of French headwater catchments. This means that between 26% and 63% of French headwaters are at risk of

  2. Effects of spatial orientation of prairie vegetation in an agricultural landscape on curve number values

    NASA Astrophysics Data System (ADS)

    Franz, K.; Dziubanski, D.; Helmers, M. J.

    2015-12-01

    The simplicity of the Curve Number (CN) method, which summarizes an area's hydrologic soil group, land cover, treatment, and hydrologic condition into a single number, make it a consistently popular choice for modelers. When multiple land cover types are present, a weighted average of the CNs is used. However, the weighted CN does not account for the spatial distribution of different land cover types within the watershed. To overcome this limitation, it becomes necessary to discretize the model into homogenous subunits, perhaps even to the hillslope scale, leading to a more complex model application. The objective of this study is to empirically derive CN values that reflect the effects of placements of native prairie vegetation (NPV) within agricultural landscapes. We derived CN values using precipitation and runoff data from (May 1 - Sept 30 over a 7 year period (2008 - 2014) for 9 ephemeral watersheds in Iowa (USA) ranging from 0.47 to 3.19 ha. The watersheds were planted with varying extents of NPV (0%, 10%, 20%) in different watershed positions (footslope vs. contour strips), with the rest of the watershed as row crop. The derived CN values from watersheds with all row crop were consistent with published values and watersheds with NPV had an average CN reduction of 6.4%, with a maximum reduction of 11.6%. Four of the six sites with treatment had a lower CN than one calculated using a weighted average of look-up values, indicating that accounting for placement of vegetation within the landscape is important for modeling runoff with the CN method. The derived CNs were verified using the leave-one-year-out method (computing CN using data from 6 of the 7 years, and then estimating runoff on the seventh year with that CN). Nash-Sutcliffe Efficiency (NSE) values for the estimated runoff typically ranged from 0.4-0.6. Our results suggest that the new CNs could confidently be used in future modeling studies to explore the hydrologic impacts of the NPV treatments at

  3. Investigating the Environmental Effects of Agriculture Practices on Natural Resources: Scientific Contributions of the U.S. Geological Survey to Enhance the Management of Agricultural Landscapes

    USGS Publications Warehouse

    U.S. Geological Survey

    2007-01-01

    The U.S. Geological Survey (USGS) enhances and protects the quality of life in the United States by advancing scientific knowledge to facilitate effective management of hydrologic, biologic, and geologic resources. Results of selected USGS research and monitoring projects in agricultural landscapes are presented in this Fact Sheet. Significant environmental and social issues associated with agricultural production include changes in the hydrologic cycle; introduction of toxic chemicals, nutrients, and pathogens; reduction and alteration of wildlife habitats; and invasive species. Understanding environmental consequences of agricultural production is critical to minimize unintended environmental consequences. The preservation and enhancement of our natural resources can be achieved by measuring the success of improved management practices and by adjusting conservation policies as needed to ensure long-term protection.

  4. Using high resolution CIR imagery in the classification of non-cropped areas in agricultural landscapes in the UK

    NASA Astrophysics Data System (ADS)

    O'Connell, Jerome; Bradter, Ute; Benton, Tim G.

    2013-10-01

    With global food demand on course to double in the next 50 years the pressures of agricultural intensification on ecosystem services in highly managed landscapes are increasing. Within an agricultural landscape non-cropped areas are a key component of ecological heterogeneity and the sustainability of ecosystem services. Management of the landscape for both production of food and ecosystem services requires configuring the non-cropped areas in an optimal way, which, in turn requires large scale information on the distribution of non-cropped areas. In this study the Canny edge detection algorithm was used to delineate 93% of all boundaries within 422 ha of agricultural land in south east England. The resulting image was used in conjunction with vegetation indices derived from Color Infra Red (CIR) aerial photography and auxiliary landuse data in an Object Orientated (OO) Knowledge Based Classifier (KBC) to identify non-cropped areas. An overall accuracy of 94.27% (Kappa 0.91) for the KBC compared favorably with 63.04% (Kappa 0.55) for a pixel based hybrid classifier of the same area.

  5. Silicate weathering and CO2 consumption within agricultural landscapes, the Ohio-Tennessee River Basin, USA

    NASA Astrophysics Data System (ADS)

    Fortner, S. K.; Lyons, W. B.; Carey, A. E.; Shipitalo, M. J.; Welch, S. A.; Welch, K. A.

    2011-09-01

    Myriad studies have shown the extent of human alteration to global biogeochemical cycles. Yet, there is only a limited understanding of the influence that humans have over silicate weathering fluxes; fluxes that have regulated atmospheric carbon dioxide concentrations and global climate over geologic timescales. Natural landscapes have been reshaped into agricultural ones to meet food needs for growing world populations. These processes modify soil properties, alter hydrology, affect erosion, and consequently impact water-soil-rock interactions such as chemical weathering. Dissolved silica (DSi), Ca2+, Mg2+, NO3-, and total alkalinity were measured in water samples collected from five small (0.65 to 38.3 ha) gauged watersheds at the North Appalachian Experimental Watershed (NAEW) near Coshocton, Ohio, USA. The sampled watersheds in this unglaciated region include: a forested site (70+ yr stand), mixed agricultural use (corn, forest, pasture), an unimproved pasture, tilled corn, and a recently (<3 yr) converted no-till corn field. The first three watersheds had perennial streams, but the two corn watersheds only produced runoff during storms and snowmelt. For the perennial streams, total discharge was an important control of dissolved silicate transport. Median DSi yields (22.1-30.8 kg ha-1 a-1) were similar to the median of annual averages between 1979-2009 for the much larger Ohio-Tennessee River Basin (25.6 kg ha-1 a-1). Corn watersheds, which only had surface runoff, had substantially lower DSi yields (<5.3 kg ha-1 a-1) than the perennial-flow watersheds. The lack of contributions from Si-enriched groundwater largely explained their much lower DSi yields with respect to sites having baseflow. A significant positive correlation between the molar ratio of (Ca2+ + Mg2)/alkalinity to DSi in the tilled corn and the forested site suggested, however, that silicate minerals weathered as alkalinity was lost via enhanced nitrification resulting from fertilizer additions

  6. Occupancy and abundance of wintering birds in a dynamic agricultural landscape

    USGS Publications Warehouse

    Miller, Mark W.; Pearlstine, Elise V.; Dorazio, Robert M.; Mazzotti, Frank J.

    2011-01-01

    Assessing wildlife management action requires monitoring populations, and abundance often is the parameter monitored. Recent methodological advances have enabled estimation of mean abundance within a habitat using presence–absence or count data obtained via repeated visits to a sample of sites. These methods assume populations are closed and intuitively assume habitats within sites change little during a field season. However, many habitats are highly variable over short periods. We developed a variation of existing occupancy and abundance models that allows for extreme spatio-temporal differences in habitat, and resulting changes in wildlife abundance, among sites and among visits to a site within a field season. We conducted our study in sugarcane habitat within the Everglades Agricultural Area southeast of Lake Okeechobee in south Florida. We counted wintering birds, primarily passerines, within 245 sites usually 5 times at each site during December 2006–March 2007. We estimated occupancy and mean abundance of birds in 6 vegetation states during the sugarcane harvest and allowed these parameters to vary temporally or spatially within a vegetation state. Occupancy and mean abundance of the common yellowthroat (Geothlypis trichas) was affected by structure of sugarcane and uncultivated edge vegetation (occupancy=1.00 [95%CĪ=0.96–1.00] and mean abundance=7.9 [95%CĪ=3.2–19.5] in tall sugarcane with tall edge vegetation versus 0.20 [95%CĪ=0.04–0.71] and 0.22 [95%CĪ=0.04–1.2], respectively, in short sugarcane with short edge vegetation in one half of the study area). Occupancy and mean abundance of palm warblers (Dendroica palmarum) were constant (occupancy=1.00, 95%CĪ=0.69–1.00; mean abundance=18, 95%CĪ=1–270). Our model may enable wildlife managers to assess rigorously effects of future edge habitat management on avian distribution and abundance within agricultural landscapes during winter or the breeding season. The model may also help

  7. Occupancy and abundance of wintering birds in a dynamic agricultural landscape

    USGS Publications Warehouse

    Miller, M.W.; Pearlstine, E.V.; Dorazio, R.M.; Mazzotti, F.J.

    2011-01-01

    Assessing wildlife management action requires monitoring populations, and abundance often is the parameter monitored. Recent methodological advances have enabled estimation of mean abundance within a habitat using presence-absence or count data obtained via repeated visits to a sample of sites. These methods assume populations are closed and intuitively assume habitats within sites change little during a field season. However, many habitats are highly variable over short periods. We developed a variation of existing occupancy and abundance models that allows for extreme spatio-temporal differences in habitat, and resulting changes in wildlife abundance, among sites and among visits to a site within a field season. We conducted our study in sugarcane habitat within the Everglades Agricultural Area southeast of Lake Okeechobee in south Florida. We counted wintering birds, primarily passerines, within 245 sites usually 5 times at each site during December 2006-March 2007. We estimated occupancy and mean abundance of birds in 6 vegetation states during the sugarcane harvest and allowed these parameters to vary temporally or spatially within a vegetation state. Occupancy and mean abundance of the common yellowthroat (Geothlypis trichas) was affected by structure of sugarcane and uncultivated edge vegetation (occupancy = 1.00 [95%C?? = 0.96-1.00] and mean abundance = 7.9 [95%C?? = 3.2-19.5] in tall sugarcane with tall edge vegetation versus 0.20 [95%C?? = 0.04-0.71] and 0.22 [95%C?? = 0.04-1.2], respectively, in short sugarcane with short edge vegetation in one half of the study area). Occupancy and mean abundance of palm warblers (Dendroica palmarum) were constant (occupancy = 1.00, 95%C?? = 0.69-1.00; mean abundance = 18, 95%C?? = 1-270). Our model may enable wildlife managers to assess rigorously effects of future edge habitat management on avian distribution and abundance within agricultural landscapes during winter or the breeding season. The model may also help

  8. Exposure of native bees foraging in an agricultural landscape to current-use pesticides.

    PubMed

    Hladik, Michelle L; Vandever, Mark; Smalling, Kelly L

    2016-01-15

    The awareness of insects as pollinators and indicators of environmental quality has grown in recent years, partially in response to declines in honey bee (Apis mellifera) populations. While most pesticide research has focused on honey bees, there has been less work on native bee populations. To determine the exposure of native bees to pesticides, bees were collected from an existing research area in northeastern Colorado in both grasslands (2013-2014) and wheat fields (2014). Traps were deployed bi-monthly during the summer at each land cover type and all bees, regardless of species, were composited as whole samples and analyzed for 136 current-use pesticides and degradates. This reconnaissance approach provides a sampling of all species and represents overall pesticide exposure (internal and external). Nineteen pesticides and degradates were detected in 54 composite samples collected. Compounds detected in >2% of the samples included: insecticides thiamethoxam (46%), bifenthrin (28%), clothianidin (24%), chlorpyrifos (17%), imidacloprid (13%), fipronil desulfinyl (7%; degradate); fungicides azoxystrobin (17%), pyraclostrobin (11%), fluxapyroxad (9%), and propiconazole (9%); herbicides atrazine (19%) and metolachlor (9%). Concentrations ranged from 1 to 310 ng/g for individual pesticides. Pesticides were detected in samples collected from both grasslands and wheat fields; the location of the sample and the surrounding land cover at the 1000 m radius influenced the pesticides detected but because of a small number of temporally comparable samples, correlations between pesticide concentration and land cover were not significant. The results show native bees collected in an agricultural landscape are exposed to multiple pesticides, these results can direct future research on routes/timing of pesticide exposure and the design of future conservation efforts for pollinators. PMID:26520270

  9. Belowground Water Dynamics Under Contrasting Annual and Perennial Plant Communities in an Agriculturally-Dominated Landscape

    NASA Astrophysics Data System (ADS)

    Mora, G.; Asbjornsen, H.; Helmers, M. J.; Shepherd, G. W.

    2005-12-01

    The conversion from grasslands and forests to row-crops in the Midwest has affected soil water cycling because plant characteristics are one of the main parameters determining soil storage capacity, infiltration rates, and surface runoff. Little is known, however, about the extent of modification of soil water dynamics under different plant communities. To address this important issue, we are documenting soil water dynamics under contrasting perennial and annual plant communities in an agriculturally-dominated landscape. Measurements of soil moisture and depths of uptake of source water were obtained for six vegetative cover types (corn and soybean field, brome pasture, degraded savanna, restored savanna, and restored prairie) at the Neal Smith National Wildlife Refuge in Prairie City, Iowa. The depths of uptake of soil water were determined on the basis of oxygen isotope composition of soil water and stem water. Measurements were performed once a month during an entire growing season. Preliminary results indicate that soil water present under the different vegetation types show similar profiles with depth during the dry months. Soil water in the upper 5 cm is enriched in oxygen-18 by about 5 per mil relative to soil water at 100 cm. Our preliminary results also indicate that the isotopic composition of stem water from annual plants is typically higher by about 2 per mil relative to that of stem water from perennial plants during the dry period. Whereas the oxygen isotopic composition for corn stem water is -5.49 per mil, that for elm and oak stem water is -7.62 and -7.51 per mil, respectively. The higher isotope values for corn suggest that annual crop plants are withdrawing water from shallower soil horizons relative to perennial plants. Moreover, our preliminary data suggest lower moisture content in soil under annual plant cover. We propose that the presence of deeper roots in the perennial vegetation allows these plants to tap into deeper water sources when

  10. Characterizing Ice Nucleating Particles Emitted from Agricultural Activities and Natural Landscapes

    NASA Astrophysics Data System (ADS)

    Suski, K. J.; Levin, E. J.; DeMott, P. J.; Kreidenweis, S. M.; Hill, T. C. J.

    2015-12-01

    Soil dust and plant fragment emissions from agricultural harvesting and natural ecosystems are two potentially large, yet unquantified and largely uncharacterized, sources of ice nucleating particles (INPs). Both organic and mineral components have been shown to contribute to the ice-nucleating ability of soil dust, but apart from the likely presence of ice nucleation-active bacteria, little is known about the ice nucleating potential of plant tissues. This work aims to identify and differentiate the organic and inorganic contributions of soil and plant INP sources emitted from harvesting activities and natural landscapes. For this purpose, the CSU Continuous Flow Diffusion Chamber (CFDC) and the Ice Spectrometer (IS) were utilized in a combination of ambient measurements and laboratory studies. Small variability and low INP numbers (< 10 L-1 at -30 °C) characterized measurements made in air over the grazed Pawnee National Grassland in Colorado, while more variable INP over croplands around the DOE-ARM SGP site in Oklahoma appear linked to regional wind, humidity, and rainfall conditions. Harvesting of milo (grain sorghum), soybean, and wheat at an experimental research farm in Kansas resulted in spikes of INPs, with wheat harvesting producing the largest INP concentrations (up to 100 L-1 at -30 °C). In-situ use of heating tubes upstream of the CFDC to deactivate organic INP showed that milo and wheat harvest emissions showed a stronger reduction of INPs at warm temperatures than soybean emissions, suggesting a larger contribution of organics to their INP activity. Further characterization of the sources and organic and inorganic contributions to terrestrially emitted INPs by comparison to laboratory studies on collected soil dust and plant samples will also be presented.

  11. Patch occupancy, number of individuals and population density of the Marbled White in a changing agricultural landscape

    NASA Astrophysics Data System (ADS)

    Lenda, Magdalena; Skórka, Piotr

    2010-09-01

    Metapopulation theory predicts the occurrence of animals in habitat patches. In this paper, we tested predictions based on this theory, including effects of spatial autocorrelation, to describe factors affecting the presence, local number of individuals and density of the Marbled White butterfly Melanargia galathea in habitat patches spread across the agricultural landscape of southern Poland. This agricultural landscape has undergone significant changes in recent decades due to the country's political transformation and is currently characterized by a large proportion of fallow (abandoned) land. We compared 48 occupied habitat patches with 60 unoccupied ones. Positive spatial autocorrelation was found in the number and density of individuals in habitat patches. The probability of patch occupancy was higher for patches that were larger, had a higher proportion of edges, were located closer to the nearest neighbouring local population and to the nearest piece of fallow, contained a smaller area of cut grass, and also had more nectar resources. The number of Marbled Whites in habitat patches was positively related to the patch area, the distance to the nearest fallow and the abundance of nectar resources, but was negatively related to the density of shrubs. The density of individuals was positively related to abundance of flowers, proportion of edge in a patch and distance to the nearest fallow, but it was negatively related to patch area, vegetation height and grass cover. These results indicate that recent land-use changes in agricultural landscapes have had both positive and negative effects on the presence and local number of individuals and density of the Marbled White. These changes affect the metapopulation of the species through changes in habitat quality and landscape connectivity in the area surrounding habitat patches.

  12. Analysis of Employment Flow of Landscape Architecture Graduates in Agricultural Universities

    ERIC Educational Resources Information Center

    Yao, Xia; He, Linchun

    2012-01-01

    A statistical analysis of employment flow of landscape architecture graduates was conducted on the employment data of graduates major in landscape architecture in 2008 to 2011. The employment flow of graduates was to be admitted to graduate students, industrial direction and regional distribution, etc. Then, the features of talent flow and factors…

  13. Patterns and Drivers of Scattered Tree Loss in Agricultural Landscapes: Orchard Meadows in Germany (1968-2009)

    PubMed Central

    Plieninger, Tobias; Levers, Christian; Mantel, Martin; Costa, Augusta; Schaich, Harald; Kuemmerle, Tobias

    2015-01-01

    Scattered trees support high levels of farmland biodiversity and ecosystem services in agricultural landscapes, but they are threatened by agricultural intensification, urbanization, and land abandonment. This study aimed to map and quantify the decline of orchard meadows (scattered fruit trees of high nature conservation value) for a region in Southwestern Germany for the 1968 2009 period and to identify the driving forces of this decline. We derived orchard meadow loss from 1968 and 2009 aerial images and used a boosted regression trees modelling framework to assess the relative importance of 18 environmental, demographic, and socio-economic variables to test five alternative hypothesis explaining orchard meadow loss. We found that orchard meadow loss occurred in flatter areas, in areas where smaller plot sizes and fragmented orchard meadows prevailed, and in areas near settlements and infrastructure. The analysis did not confirm that orchard meadow loss was higher in areas where agricultural intensification was stronger and in areas of lower implementation levels of conservation policies. Our results demonstrated that the influential drivers of orchard meadow loss were those that reduce economic profitability and increase opportunity costs for orchards, providing incentives for converting orchard meadows to other, more profitable land uses. These insights could be taken up by local- and regional-level conservation policies to identify the sites of persistent orchard meadows in agricultural landscapes that would be prioritized in conservation efforts. PMID:25932914

  14. Patterns and drivers of scattered tree loss in agricultural landscapes: orchard meadows in Germany (1968-2009).

    PubMed

    Plieninger, Tobias; Levers, Christian; Mantel, Martin; Costa, Augusta; Schaich, Harald; Kuemmerle, Tobias

    2015-01-01

    Scattered trees support high levels of farmland biodiversity and ecosystem services in agricultural landscapes, but they are threatened by agricultural intensification, urbanization, and land abandonment. This study aimed to map and quantify the decline of orchard meadows (scattered fruit trees of high nature conservation value) for a region in Southwestern Germany for the 1968 2009 period and to identify the driving forces of this decline. We derived orchard meadow loss from 1968 and 2009 aerial images and used a boosted regression trees modelling framework to assess the relative importance of 18 environmental, demographic, and socio-economic variables to test five alternative hypothesis explaining orchard meadow loss. We found that orchard meadow loss occurred in flatter areas, in areas where smaller plot sizes and fragmented orchard meadows prevailed, and in areas near settlements and infrastructure. The analysis did not confirm that orchard meadow loss was higher in areas where agricultural intensification was stronger and in areas of lower implementation levels of conservation policies. Our results demonstrated that the influential drivers of orchard meadow loss were those that reduce economic profitability and increase opportunity costs for orchards, providing incentives for converting orchard meadows to other, more profitable land uses. These insights could be taken up by local- and regional-level conservation policies to identify the sites of persistent orchard meadows in agricultural landscapes that would be prioritized in conservation efforts. PMID:25932914

  15. Challenges in linking agricultural soil erosion studies to landscape scale processes

    NASA Astrophysics Data System (ADS)

    Huang, C.-H.; Norton, L. D.; Flanagan, D. C.

    2009-04-01

    have to shift from the annual cycle of crop management and rotation, i.e., a field scale process, to a much longer time scale as sediment transport and deposition processes in the landscape have a very long response time. Agricultural management practices have different response times depending on where the focus is. Crop yield and water conservation can usually be observed in annual cycles. Changes in aggregate stability and soil erodibility can take several years or even decades. It is often observed that sediments eroded from a field are deposited within the field boundary and sediments transported in stream channels may have been those already deposited decades ago in stream banks and flood plains. Without knowing the transient nature of the sediment movement, or a distribution of travel time for the sediments from fields to stream channels, it can be very difficult to assess the conservation or management effects at the watershed scale where geomorphic processes become dominant. In this presentation, we will provide a cursory review of US agricultural soil erosion research and development, which was intended for developing field scale erosion prediction technology. We will then discuss how we propose to address the scaling issue in assessing conservation effects at the watershed scale for sediments.

  16. Pesticide exposure on sloths (Bradypus variegatus and Choloepus hoffmanni) in an agricultural landscape of Northeastern Costa Rica.

    PubMed

    Pinnock Branford, Margaret Verónica; de la Cruz, Elba; Solano, Karla; Ramírez, Oscar

    2014-01-01

    Between 2005 and 2008, wild Bradypus variegatus and Choloepus hoffmanni inhabiting an agricultural landscape and captive animals from a rescue center in Northeastern Costa Rica were studied to assess exposure to pesticides. A total of 54 animals were sampled: 42 wild sloths captured at an agricultural landscape and 12 captive animals from a rescue center. Pesticides' active ingredients were determined in three sample matrices: hair, aqueous mixture (paws' wash) and cotton gauze (mouth clean) based on multi-residue gas chromatography methods. Recoveries tests ranged from 73 to 146% and relative standard deviations were less than 20% throughout all the recovery tests. Active ingredients detected in sloths samples were ametryn, chlorothalonil, chlorpyrifos, diazinon, difenoconazole, ethoprophos and thiabendazole. These active ingredients were used in intensive agricultural production for bananas, pineapples and other crops. Blood plasma cholinesterase activity (PChE) was determined by the Ellman method modified for micro plates. Enzyme activity determination was normalized to protein content in the samples according to Bradford method. Wild sloth PChE activity was similar for both species while sloths in captivity showed differences between species. Enzyme activity was significantly lower for two-toed sloths. This study showed that sloths were exposed to pesticides that caused acute and chronic effect in mammals and can also be a threat to other wildlife species. There is a need to better understand the potential effects of exposure to pesticides in sloths and other wild mammal populations, especially those threatened or endangered. More studies in this field must be carried out on the wildlife fauna inhabiting the agricultural landscape and its surroundings. PMID:24579518

  17. Quantify Effects of Integrated Land Management on Water Quality in Agricultural Landscape in South Fork Watershed, Iowa River

    NASA Astrophysics Data System (ADS)

    Ha, M.; Wu, M. M.

    2014-12-01

    Sustainable biofuel feedstock production — environmental sustainability and economic sustainability — may be achieved by using a multi-faceted approach. This study focuses on quantifying the water sustainability of an integrated landscaping strategy, by which current land use and land management, cropping system, agricultural Best Management Practices (BMPs), and economics play equal roles. The strategy was applied to the South Fork watershed, IA, including the tributaries of Tipton and Beaver Creeks, which expand to 800-km2 drainage areas. The watershed is an agricultural dominant area covered with row-crops production. On the basis of profitability, switchgrass was chosen as a replacement for row crops in low-productivity land. Areas for harvesting agricultural residue were selected on the basis of soil conservation principals. Double cropping with a cover crop was established to further reduce soil loss. Vegetation buffer strips were in place at fields and in riparian areas for water quality control, resource conservation, and eco service improvement. The Soil and Water Assessment Tool (SWAT) was applied to evaluate source reduction under various management schemes and land use changes. SWAT modeling incorporated 10-yr meteorological information, soil data, land slope classification, land use, four-year crop-rotation cycle, and management operations. Tile drain and pothole parameters were modeled to assess the fate and transport of nutrients. The influence of landscape management and cropping systems on nitrogen and phosphorus loadings, erosion process, and hydrological performance at the sub-watershed scale was analyzed and key factors identified. Results suggest strongly that incorporating agricultural BMPs and conservation strategies into integrated landscape management for certain energy crops in row-crop production regions can be economical and environmentally sustainable.

  18. Native wildflower plantings support wild bee abundance and diversity in agricultural landscapes across the United States.

    PubMed

    Williams, Neal M; Ward, Kimiora L; Pope, Nathaniel; Isaacs, Rufus; Wilson, Julianna; May, Emily A; Ellis, Jamie; Daniels, Jaret; Pence, Akers; Ullmann, Katharina; Peters, Jeff

    2015-12-01

    Global trends in pollinator-dependent crops have raised awareness of the need to support managed and wild bee populations to ensure sustainable crop production. Provision of sufficient forage resources is a key element for promoting bee populations within human impacted landscapes, particularly those in agricultural lands where demand for pollination service is high and land use and management practices have reduced available flowering resources. Recent government incentives in North America and Europe support the planting of wildflowers to benefit pollinators; surprisingly, in North America there has been almost no rigorous testing of the performance of wildflower mixes, or their ability to support wild bee abundance and diversity. We tested different wildflower mixes in a spatially replicated, multiyear study in three regions of North America where production of pollinator-dependent crops is high: Florida, Michigan, and California. In each region, we quantified flowering among wildflower mixes composed of annual and perennial species, and with high and low relative diversity. We measured the abundance and species richness of wild bees, honey bees, and syrphid flies at each mix over two seasons. In each region, some but not all wildflower mixes provided significantly greater floral display area than unmanaged weedy control plots. Mixes also attracted greater abundance and richness of wild bees, although the identity of best mixes varied among regions. By partitioning floral display size from mix identity we show the importance of display size for attracting abundant and diverse wild bees. Season-long monitoring also revealed that designing mixes to provide continuous bloom throughout the growing season is critical to supporting the greatest pollinator species richness. Contrary to expectation, perennials bloomed in their first season, and complementarity in attraction of pollinators among annuals and perennials suggests that inclusion of functionally diverse

  19. Some physicochemical properties of surface layer soils shelterbelts in agricultural landscape

    NASA Astrophysics Data System (ADS)

    Jaskulska, R.; Szajdak, L.

    2009-04-01

    Shelterbelts belong to very efficient biogeochemical barriers. They decrease the migration of chemical compounds between ecosystems. The investigations were carried out in the Chlapowski's Agroecological Park in Turew situated 40 km South-West of Poznań, Poland. This area is located on loamy soils, which contains 70% cultivated fields and 14% shelterbelts and small afforestations. The shelterbelts represent different ages and the content of plants as well as humus quantity in surface layer. The first one is 100-year-old shelterbelt, where predominant species is Crataegus monogyna Jacq., Quercus rober L., and Fraxinus excelsior (L.) and is characterized by a well-developed humus level. The other one is 14-year-old shelterbelt. It includes 13 species of trees and revealed a small amount of humus. The soil under both shelterbelts is mineral, grey-brown podzolic in surface layer compound from light loamy sands and weakly loamy sands. The soil samples were taken from surface layer (0-20 cm). pH 1N KCl, hydrolytic acidity, cation-exchange capacity, total proper area, total organic carbon and dissociation constants were determined in soils. The study showed that the soil under shelterbelts revealed acidic properties. It was observed that soils of 100-year-old shelterbelt characterizing lowest values pH = 4.2 revealed highest values of hydrolytic acidity equaled to 7.8 cmol(+)ṡkg-1. The physicochemical properties of investigated soils shoved specific surface areas (22.8 m2ṡg-1), cationic sorptive capacity (12.9 cmol(+)ṡkg-1). TOC (1.6%) 100-year-old shelterbelt was higher than in 14-year-old shelterbelt. The dissociation constants were determined by potentiometric titration. This investigation revealed that the pK value was the highest in the humus of 100-year-old shelterbelt (pKa = 3.1). However, soils of 14-year-old shelterbelt characterized by the lovest pK equaled to 2.8. The surface layer soils shelterbelts in agricultural landscape with good humus development

  20. Control of the spread of inorganic elements by shelterbelt in agricultural landscape

    NASA Astrophysics Data System (ADS)

    Szajdak, L.; Życzyńska-Bałoniak, I.

    2009-04-01

    A better understanding of the impact of shelterbelt on the decrease the quantities of chemical compounds in ground water should increase our ability to predict the improvement of the quality of ground water. The objective of this study was to evaluate the effect of shelterbelt on the decrease of calcium, magnesium and inorganic carbon in ground water passing through the shelterbelt from adjoining cultivated fields. The investigations were carried out in Turew in Chlapowski's Agroecological Park situated 40 km South-West of Poznań (West Polish Lowland). This area is located on loamy soils, which contains 70% cultivated fields, 12% meadows and pastures and approximately 14% afforestations including well developed network of shelterbelts (mid-field rows of trees afforestation). The established network of shelterbelts in Turew is the unique in Europe. Ground water under cultivated field and shelterbelt from the artificial wells ones a month during 7 years from 2000 to 2006 was sampled and investigated. Ground water under shelterbelt flows away from adjoining cultivated field and passing through the shelterbelt. The first distance of this shelterbelt 104 m long is located on mineral soils (division-autogenic soils, order-brown forest soils, type-hapludalfs, subtype-glossudalfs) next from 104 to 125 m on mineral organic soils (division-hydrogenic soils, order-post-bog, soils, type-mucky soils, subtype-muckous). Calcium, magnesium and mineral carbon quantities have been investigated in the ground water of shelterbelts. The differences among the concentrations of calcium, magnesium and mineral carbon were attributed solely of width of the shelterbelt. Shelterbelt revealed the improvement in the quality of ground water. The biogeochemical barrier in the form of shelterbelt efficiently decreases the concentration of chemical substances calcium to 26%, magnesium to 25% and also mineral carbon 70,5%. Concerns over the environmental impacts of the elements of agricultural

  1. Strong Discrepancies between Local Temperature Mapping and Interpolated Climatic Grids in Tropical Mountainous Agricultural Landscapes

    PubMed Central

    Faye, Emile; Herrera, Mario; Bellomo, Lucio; Silvain, Jean-François; Dangles, Olivier

    2014-01-01

    Bridging the gap between the predictions of coarse-scale climate models and the fine-scale climatic reality of species is a key issue of climate change biology research. While it is now well known that most organisms do not experience the climatic conditions recorded at weather stations, there is little information on the discrepancies between microclimates and global interpolated temperatures used in species distribution models, and their consequences for organisms’ performance. To address this issue, we examined the fine-scale spatiotemporal heterogeneity in air, crop canopy and soil temperatures of agricultural landscapes in the Ecuadorian Andes and compared them to predictions of global interpolated climatic grids. Temperature time-series were measured in air, canopy and soil for 108 localities at three altitudes and analysed using Fourier transform. Discrepancies between local temperatures vs. global interpolated grids and their implications for pest performance were then mapped and analysed using GIS statistical toolbox. Our results showed that global interpolated predictions over-estimate by 77.5±10% and under-estimate by 82.1±12% local minimum and maximum air temperatures recorded in the studied grid. Additional modifications of local air temperatures were due to the thermal buffering of plant canopies (from −2.7°K during daytime to 1.3°K during night-time) and soils (from −4.9°K during daytime to 6.7°K during night-time) with a significant effect of crop phenology on the buffer effect. This discrepancies between interpolated and local temperatures strongly affected predictions of the performance of an ectothermic crop pest as interpolated temperatures predicted pest growth rates 2.3–4.3 times lower than those predicted by local temperatures. This study provides quantitative information on the limitation of coarse-scale climate data to capture the reality of the climatic environment experienced by living organisms. In highly heterogeneous

  2. High-Resolution Biogeochemical Simulation Identifies Practical Opportunities for Bioenergy Landscape Intensification Across Diverse US Agricultural Regions

    NASA Astrophysics Data System (ADS)

    Field, J.; Adler, P. R.; Evans, S.; Paustian, K.; Marx, E.; Easter, M.

    2015-12-01

    The sustainability of biofuel expansion is strongly dependent on the environmental footprint of feedstock production, including both direct impacts within feedstock-producing areas and potential leakage effects due to disruption of existing food, feed, or fiber production. Assessing and minimizing these impacts requires novel methods compared to traditional supply chain lifecycle assessment. When properly validated and applied at appropriate spatial resolutions, biogeochemical process models are useful for simulating how the productivity and soil greenhouse gas fluxes of cultivating both conventional crops and advanced feedstock crops respond across gradients of land quality and management intensity. In this work we use the DayCent model to assess the biogeochemical impacts of agricultural residue collection, establishment of perennial grasses on marginal cropland or conservation easements, and intensification of existing cropping at high spatial resolution across several real-world case study landscapes in diverse US agricultural regions. We integrate the resulting estimates of productivity, soil carbon changes, and nitrous oxide emissions with crop production budgets and lifecycle inventories, and perform a basic optimization to generate landscape cost/GHG frontiers and determine the most practical opportunities for low-impact feedstock provisioning. The optimization is constrained to assess the minimum combined impacts of residue collection, land use change, and intensification of existing agriculture necessary for the landscape to supply a commercial-scale biorefinery while maintaining exiting food, feed, and fiber production levels. These techniques can be used to assess how different feedstock provisioning strategies perform on both economic and environmental criteria, and sensitivity of performance to environmental and land use factors. The included figure shows an example feedstock cost-GHG mitigation tradeoff frontier for a commercial-scale cellulosic

  3. Soil management shapes ecosystem service provision and trade-offs in agricultural landscapes.

    PubMed

    Tamburini, Giovanni; De Simone, Serena; Sigura, Maurizia; Boscutti, Francesco; Marini, Lorenzo

    2016-08-31

    Agroecosystems are principally managed to maximize food provisioning even if they receive a large array of supporting and regulating ecosystem services (ESs). Hence, comprehensive studies investigating the effects of local management and landscape composition on the provision of and trade-offs between multiple ESs are urgently needed. We explored the effects of conservation tillage, nitrogen fertilization and landscape composition on six ESs (crop production, disease control, soil fertility, water quality regulation, weed and pest control) in winter cereals. Conservation tillage enhanced soil fertility and pest control, decreased water quality regulation and weed control, without affecting crop production and disease control. Fertilization only influenced crop production by increasing grain yield. Landscape intensification reduced the provision of disease and pest control. We also found tillage and landscape composition to interactively affect water quality regulation and weed control. Under N fertilization, conventional tillage resulted in more trade-offs between ESs than conservation tillage. Our results demonstrate that soil management and landscape composition affect the provision of several ESs and that soil management potentially shapes the trade-offs between them. PMID:27559064

  4. Soil and substrate morphology as witnesses of present and former agricultural landscape management

    NASA Astrophysics Data System (ADS)

    Chartin, C.; Salvador-Blanes, S.; Hinschberger, F.; Bourennane, H.; Macaire, J.-J.

    2009-04-01

    Water and tillage erosion, combined with the effect of successive regrouping of the land campaigns, have sensibly modified the morphology of cultivated hillslopes. Nowadays, we can still observe over cultivated landscapes various anthropogenic structures (e.g. lynchets) that correspond to former and/or present field limits. The aim of this work is to spatially characterise the geometry of these various structures, and to assess their relation with soil variability. The 10 ha studied site corresponds to an hillslope located in a small calcareous watershed near Tours in the Parisian Basin (France). Soils are mainly Cambisols (calcaric), Epileptic cambisols (calcaric) and Colluvic cambisols. This watershed is characterised by the presence of many soil accumulation structures and has been submitted to an important regrouping of the lands since the 1960's. The existing structures were accurately located and defined through a topographical analysis (slope, profile curvature...), and then related to past and present field limits using aerial photographies and cadastral maps. Two main morphological structures, deeply marked in the topography, are identified. The most remarkable type corresponds to well developed lynchets located at the lower part of field limits. Secondary structures, less marked than lynchets, are linked to field limits which existed at least since 1836, but that disappeared from the 1960's. These secondary structures look like longitudinal bulges placed perpendicularly to the direction of the main slope. A soil survey on these two geomorphic structure types has been performed in order to determine their specific geometry. Lynchets are characterised by a large increase in the thickness of soils: from 35 cm at 24 m upslope to more than 120 cm on its top. But, in some cases, the elevation study shows a topographical discontinuity between the top of the accumulation and the field or road below, discontinuity that is more important than the maximum soil

  5. Using fallout Cesium-137 to understand soil redistribution over agricultural landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    While it is recognized that soil erosion is highly variable in space and time, studies of the redistribution of soil within a field or watershed are limited. Our studies focus on the use of fallout Cesium-137 to understand pattern of soil movement on the landscape. It is often assumed that eroding...

  6. Spatial analyses of soil properties, terrain, and water dynamics in a semi-arid agricultural landscape

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Quantification of soil-water patterns in space and time is essential for understanding soil hydrological processes and to aid land management decisions. In undulating terrain, dynamics of profile soil water can vary by landscape position in relation to terrain attributes, soil properties, and plant ...

  7. APPLYING THE PATUXENT LANDSCAPE UNIT MODEL TO HUMAN DOMINATED ECOSYSTEMS: THE CASE OF AGRICULTURE. (R827169)

    EPA Science Inventory

    Non-spatial dynamics are core to landscape simulations. Unit models simulate system interactions aggregated within one space unit of resolution used within a spatial model. For unit models to be applicable to spatial simulations they have to be formulated in a general enough w...

  8. Promoting landscape-based crop management for food, feed, and bioenergy with precision agriculture technologies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Failure to consider natural and anthropogenic soil variability within fields and across landscapes in the development and implementation of soil and crop management systems can limit crop production and degrade soil and water resources. Targeting of management systems based on soil variability is ne...

  9. Regional gene flow and population structure of the wind-dispersed plant species Hypochaeris radicata (Asteraceae) in an agricultural landscape.

    PubMed

    Mix, C; Arens, P F P; Rengelink, R; Smulders, M J M; Van Groenendael, J M; Ouborg, N J

    2006-06-01

    Using microsatellites, we investigated population structure and gene flow of the short-lived, wind-dispersed plant species Hypochaeris radicata in a fragmented agricultural landscape where more than 99% of the nutrient-poor grasslands have disappeared over the last century. We sampled populations in the few remaining high density populations in conservation areas, as well as individuals that occurred, with lower densities, in linear landscape elements, at two spatial scales. In a re-inventory of the landscape, after 3 years, both extinctions and colonizations of populations were observed. Contrary to expectations, no differences in genetic diversity between high and low density populations were observed. Both types of populations had relatively high levels of diversity. Overall genetic differentiation (theta) was 0.04 and significantly different from zero (P < 0.01). A significant isolation-by-distance pattern was found when all populations were simultaneously analysed (r = 0.24, P = 0.013). Isolation by distance was (marginally) significant at the small scale (r = 0.32, P = 0.06), whereas nonsignificant at the large spatial scale (r = -0.05, P = 0.66). A maximization-of-explained-variance procedure resulted in a threshold distance of 3.5 km above which populations were effectively genetically isolated. An additional partial exclusion Bayesian-based assignment test showed that overall 32.3% of the individuals were assigned to their population of origin, 48% were assigned to another population in the area and 19.7% were not assigned. Together, these results suggest high levels of gene flow. Seed dispersal contributes to the observed gene flow up to several hundred metres, which is higher than previously modelled using aerodynamic models on seed dispersal of H. radicata. We discuss the consequences of these results for an evaluation of the probability of persistence of this species in the fragmented landscape. PMID:16689895

  10. Control of the spread of inorganic elements by shelterbelt in agricultural landscape

    NASA Astrophysics Data System (ADS)

    Życzyńska-Bałoniak, Irena; Wojciech Szajdak, Lech

    2010-05-01

    water samples were taken from the wells located (a) in the border between adjoining cultivated fields and shelterbelts, and (b) in the distances 62 m, 104 m and 125 m from the edge of the shelterbelt. The concentrations of calciumand magnesium and also mineral carbon were studied by examining ground water filtered by the filter paper Whatman GT/C. The concentrations of calcium and magnesium were investigated by the method by Hermanowicz. Dry masses were isolated by the freeze-dried and drying to the constant of weight at 105oC. Total organic carbon, dissolved organic carbon and mineral carbon were measured on Total Organic Carbon Analyzer 5050A, ASI 5000A auto sampler, SSM - 5000A solid sample module, (Shimadzu, Japan). Total amount of yearly rainfall was in 2000 - 671 mm, 2001 - 544 mm, 2002 - 495 mm, 2003 - 449 mm, 2004 - 672 mm, 2005 - 551 mm, 2006 - 578 mm. Mean temperatures ranged from 9.2 to 13.3oC. The highest temperature +23.5oC was measured in July 2000, and the lowest -6.4oC observed in January 2006. The precision based on replicate analyses, were ± 4% for Ca+2, ± 3% for Mg+2, ± 4% for dry mass. All the determinations were run in triplicate, and the results were averaged. The differences among the concentrations of calcium, magnesium and mineral carbon were attributed solely of width of the shelterbelt. Shelterbelt revealed the improvement in the quality of ground water. Concerns over the environmental impacts of the elements of agricultural landscapes have focused attention on the study of calcium, magnesium, mineral carbon in ground water. These investigations have shown high contents of chemical compounds migrates ground water from cultivated fields. Ground water under cultivated field revealed high concentrations of calcium, which yearly mean contents are equaled from 81.9 to 179.2 mg/l. It was proved that biogeochemical barrier such as shelterbelt efficiency decrease the quantity of chemical compounds in ground water. The highest decrease of determined

  11. Control of the spread of inorganic elements by shelterbelt in agricultural landscape

    NASA Astrophysics Data System (ADS)

    Życzyńska-Bałoniak, Irena; Wojciech Szajdak, Lech

    2010-05-01

    water samples were taken from the wells located (a) in the border between adjoining cultivated fields and shelterbelts, and (b) in the distances 62 m, 104 m and 125 m from the edge of the shelterbelt. The concentrations of calciumand magnesium and also mineral carbon were studied by examining ground water filtered by the filter paper Whatman GT/C. The concentrations of calcium and magnesium were investigated by the method by Hermanowicz. Dry masses were isolated by the freeze-dried and drying to the constant of weight at 105oC. Total organic carbon, dissolved organic carbon and mineral carbon were measured on Total Organic Carbon Analyzer 5050A, ASI 5000A auto sampler, SSM - 5000A solid sample module, (Shimadzu, Japan). Total amount of yearly rainfall was in 2000 - 671 mm, 2001 - 544 mm, 2002 - 495 mm, 2003 - 449 mm, 2004 - 672 mm, 2005 - 551 mm, 2006 - 578 mm. Mean temperatures ranged from 9.2 to 13.3oC. The highest temperature +23.5oC was measured in July 2000, and the lowest -6.4oC observed in January 2006. The precision based on replicate analyses, were ± 4% for Ca+2, ± 3% for Mg+2, ± 4% for dry mass. All the determinations were run in triplicate, and the results were averaged. The differences among the concentrations of calcium, magnesium and mineral carbon were attributed solely of width of the shelterbelt. Shelterbelt revealed the improvement in the quality of ground water. Concerns over the environmental impacts of the elements of agricultural landscapes have focused attention on the study of calcium, magnesium, mineral carbon in ground water. These investigations have shown high contents of chemical compounds migrates ground water from cultivated fields. Ground water under cultivated field revealed high concentrations of calcium, which yearly mean contents are equaled from 81.9 to 179.2 mg/l. It was proved that biogeochemical barrier such as shelterbelt efficiency decrease the quantity of chemical compounds in ground water. The highest decrease of determined

  12. Can conservation trump impacts of climate change and extremes on soil erosion in agricultural landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Preservation of top soil is critical for the long term sustainability of agricultural productivity, food security, and biodiversity. However, today’s growing population and increasing demand for food and fiber is stressing the agricultural soil and water resources. Climate change imposes additional ...

  13. Remote Sensing of Wetland Hydrology: Implications for Water Quality Management in Agricultural Landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to the substantial effect of agriculture on the ability of wetlands to function, the U.S. Department of Agriculture (USDA) serves a key role in wetland conservation and restoration. In order for the USDA to allocate funds to best manage wetlands, a better understanding of wetland functioning is ...

  14. Even the smallest non-crop habitat islands could be beneficial: distribution of carabid beetles and spiders in agricultural landscape.

    PubMed

    Knapp, Michal; Řezáč, Milan

    2015-01-01

    Carabid beetles and ground-dwelling spiders inhabiting agroecosystems are beneficial organisms with a potential to control pest species. Intensification of agricultural management and reduction of areas covered by non-crop vegetation during recent decades in some areas has led to many potentially serious environmental problems including a decline in the diversity and abundance of beneficial arthropods in agricultural landscapes. This study investigated carabid beetle and spider assemblages in non-crop habitat islands of various sizes (50 to 18,000 square metres) within one large field, as well as the arable land within the field, using pitfall traps in two consecutive sampling periods (spring to early summer and peak summer). The non-crop habitat islands situated inside arable land hosted many unique ground-dwelling arthropod species that were not present within the surrounding arable land. Even the smallest non-crop habitat islands with areas of tens of square metres were inhabited by assemblages substantially different from these inhabiting arable land and thus enhanced the biodiversity of agricultural landscapes. The non-crop habitat area substantially affected the activity density, recorded species richness and recorded species composition of carabid and ground-dwelling spider assemblages; however, the effects were weakened when species specialised to non-crop habitats species were analysed separately. Interestingly, recorded species richness of spiders increased with non-crop habitat area, whereas recorded species richness of carabid beetles exhibited an opposite trend. There was substantial temporal variation in the spatial distribution of ground-dwelling arthropods, and contrasting patterns were observed for particular taxa (carabid beetles and spiders). In general, local environmental conditions (i.e., non-crop habitat island tree cover, shrub cover, grass cover and litter depth) were better determinants of arthropod assemblages than non-crop habitat island

  15. Use of radar remote sensing (RADARSAT) to map winter wetland habitat for shorebirds in an agricultural landscape

    USGS Publications Warehouse

    Taft, Oriane W.; Haig, Susan M.

    2004-01-01

    Many of todays agricultural landscapes once held vast amounts of wetland habitat for waterbirds and other wildlife. Successful restoration of these landscapes relies on access to accurate maps of the wetlands that remain. We used C-band (5.6-cm-wavelength), HH-polarized radar remote sensing (RADARSAT) at a 38A? incidence angle (8-m resolution) to map the distribution of winter shorebird (Charadriiformes) habitat on agricultural lands in the Willamette Valley of western Oregon. We acquired imagery on three dates (10 December 1999, 27 January 2000, and 15 March 2000) and simultaneously collected ground reference data to classify radar signatures and evaluate map accuracy of four habitat classes: (1) wet with 50% vegetation (considered optimal shorebird habitat), (2) wet with > 50% vegetation, (3) dry with 50% vegetation, and (4) dry with > 50% vegetation. Overall accuracy varied from 45 to 60% among the three images, but the accuracy of focal class 1 was greater, ranging from 72 to 80%. Class 4 coverage was stable and dominated maps (40% of mapped study area) for all three dates, while coverage of class 3 decreased slightly throughout the study period. Among wet classes, class 1 was most abundant (about 30% coverage) in December and January, decreasing in March to approximately 15%. Conversely, class 2 increased dramatically from January to March, likely due to transition from class 1 as vegetation grew. This approach was successful in detecting optimal habitat for shorebirds on agricultural lands. For modest classification schemes, radar remote sensing is a valuable option for wetland mapping in areas where cloud cover is persistent.

  16. Use of radar remote sensing (RADARSAT) to map winter wetland habitat for shorebirds in an agricultural landscape.

    PubMed

    Taft, Oriane W; Haig, Susan M; Kiilsgaard, Chris

    2004-05-01

    Many of today's agricultural landscapes once held vast amounts of wetland habitat for waterbirds and other wildlife. Successful restoration of these landscapes relies on access to accurate maps of the wetlands that remain. We used C-band (5.6-cm-wavelength), HH-polarized radar remote sensing (RADARSAT) at a 38 degrees incidence angle (8-m resolution) to map the distribution of winter shorebird (Charadriiformes) habitat on agricultural lands in the Willamette Valley of western Oregon. We acquired imagery on three dates (10 December 1999, 27 January 2000, and 15 March 2000) and simultaneously collected ground reference data to classify radar signatures and evaluate map accuracy of four habitat classes: (1) wet with < or = 50% vegetation (considered optimal shorebird habitat), (2) wet with > 50% vegetation, (3) dry with < or = 50% vegetation, and (4) dry with > 50% vegetation. Overall accuracy varied from 45 to 60% among the three images, but the accuracy of focal class 1 was greater, ranging from 72 to 80%. Class 4 coverage was stable and dominated maps (40% of mapped study area) for all three dates, while coverage of class 3 decreased slightly throughout the study period. Among wet classes, class 1 was most abundant (about 30% coverage) in December and January, decreasing in March to approximately 15%. Conversely, class 2 increased dramatically from January to March, likely due to transition from class 1 as vegetation grew. This approach was successful in detecting optimal habitat for shorebirds on agricultural lands. For modest classification schemes, radar remote sensing is a valuable option for wetland mapping in areas where cloud cover is persistent. PMID:15503392

  17. Use of radar remote sensing (RADARSAT) to map winter wetland habitat for shorebirds in an agricultural landscape.

    PubMed

    Taft, Oriane W; Haig, Susan M; Kiilsgaard, Chris

    2003-08-01

    Many of today's agricultural landscapes once held vast amounts of wetland habitat for waterbirds and other wildlife. Successful restoration of these landscapes relies on access to accurate maps of the wetlands that remain. We used C-band (5.6-cm-wavelength), HH-polarized radar remote sensing (RADARSAT) at a 38 degree incidence angle (8-m resolution) to map the distribution of winter shorebird (Charadriiformes) habitat on agricultural lands in the Willamette Valley of western Oregon. We acquired imagery on three dates (10 December 1999, 27 January 2000, and 15 March 2000) and simultaneously collected ground reference data to classify radar signatures and evaluate map accuracy of four habitat classes: (1) wet with < or = 50% vegetation (considered optimal shorebird habitat), (2) wet with > 50% vegetation, (3) dry with < or = 50% vegetation, and (4) dry with > 50% vegetation. Overall accuracy varied from 45 to 60% among the three images, but the accuracy of focal class 1 was greater, ranging from 72 to 80%. Class 4 coverage was stable and dominated maps (40% of mapped study area) for all three dates, while class 3 coverage decreased slightly throughout the study period. Among wet classes, class 1 was most abundant (30% coverage) in December and January, decreasing in March by 15%. Conversely, class 2 increased dramatically from January to March, likely due to transition from class 1 as vegetation grew. This approach was successful in detecting optimal habitat for shorebirds on agricultural lands. For modest classification schemes, radar remote sensing is a valuable option for wetland mapping in areas where cloud cover is persistent. PMID:14753651

  18. Use of radar remote sensing (RADARSAT) to map winter wetland habitat for shorebirds in an agricultural landscape

    USGS Publications Warehouse

    Taft, O.W.; Haig, S.M.; Kiilsgaard, C.

    2003-01-01

    Many of today's agricultural landscapes once held vast amounts of wetland habitat for waterbirds and other wildlife. Successful restoration of these landscapes relies on access to accurate maps of the wetlands that remain. We used C-band (5.6-cm-wavelength), HH-polarized radar remote sensing (RADARSAT) at a 38?? incidence angle (8-m resolution) to map the distribution of winter shorebird (Charadriiformes) habitat on agricultural lands in the Willamette Valley of western Oregon. We acquired imagery on three dates (10 December 1999, 27 January 2000, and 15 March 2000) and simultaneously collected ground reference data to classify radar signatures and evaluate map accuracy of four habitat classes: (1) wet with ??? 50% vegetation (considered optimal shorebird habitat), (2) wet with > 50% vegetation, (3) dry with ??? 50% vegetation, and (4) dry with > 50% vegetation. Overall accuracy varied from 45 to 60% among the three images, but the accuracy of focal class 1 was greater, ranging from 72 to 80%. Class 4 coverage was stable and dominated maps (40% of mapped study area) for all three dates, while class 3 coverage decreased slightly throughout the study period. Among wet classes, class 1 was most abundant (30% coverage) in December and January, decreasing in March by 15%. Conversely, class 2 increased dramatically from January to March, likely due to transition from class 1 as vegetation grew. This approach was successful in detecting optimal habitat for shorebirds on agricultural lands. For modest classification schemes, radar remote sensing is a valuable option for wetland mapping in areas where cloud cover is persistent. ?? 2003 Springer-Verlag New York Inc.

  19. Daily Evolution of the Insect Biomass Spectrum in an Agricultural Landscape Accessed with Lidar

    NASA Astrophysics Data System (ADS)

    Brydegaard, Mikkel; Gebru, Alem; Kirkeby, Carsten; Åkesson, Susanne; Smith, Henrik

    2016-06-01

    We present measurements of atmospheric insect fauna intercepted by a static lidar transect over arable and pastoral land over one day. We observe nearly a quarter million of events which are calibrated to optical cross section. Biomass spectra are derived from the size distribution and presented against space and time. We discuss detection limits and instrument biasing, and we relate the insect observations to relevant ecological landscape features and land use. Future directions and improvements of the technique are also outlined.

  20. Application of ground-based LIDAR for gully investigation in agricultural landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Detailed scientific investigation of gullies in agricultural fields requires accurate topographic information with adequate temporal and spatial resolution. New technologies, such as ground-based LIDAR systems, are capable of generating datasets with high temporal and spatial resolutions. The spatia...

  1. EVALUATING THE IMPACT OF POLICY OPTIONS ON AGRICULTURAL LANDSCAPES: AN ALTERNATIVE-FUTURES APPROACH

    EPA Science Inventory

    Alternative-futures analysis was used to analyze different scenarios of future growth patterns and attendant resource allocations on the agricultural system of Oregon's Willamette River Basin. A stakeholder group formulated three policy alternatives: a continuation of current tr...

  2. Accelerated export of sediment and carbon from a landscape under intensive agriculture.

    PubMed

    Glendell, M; Brazier, R E

    2014-04-01

    The export of total organic carbon (particulate and dissolved) from terrestrial to aquatic ecosystems has important implications for water quality and the global carbon cycle. However, most research to date has focused on DOC losses from either forested or peaty catchments, with only limited studies examining the controls and rates of total fluvial carbon losses from agricultural catchments, particularly during storm events. This study examined the controls and fluxes of total suspended sediment (SS), total particulate (TPC) and dissolved organic carbon (DOC) from two adjacent catchments with contrasting intensive agricultural and semi-natural land-use. Data from 35 individual storm events showed that the agricultural catchment exported significantly higher SS concentrations on a storm-by-storm basis than the semi-natural catchment, with peak discharge exerting a greater control over SS, TPC and DOC concentrations. Baseflow DOC concentrations in the agricultural catchment were significantly higher. DOC quality monitored during one simultaneous rainfall event differed between the two study catchments, with more humic, higher molecular weight compounds prevailing in the agricultural catchment and lower molecular weight compounds prevailing in the semi-natural catchment. During an eight month period for which a comparable continuous turbidity record was available, the estimated SS yields from the agricultural catchment were higher than from the semi-natural catchment. Further, the agricultural catchment exported proportionally more TPC and a comparable amount of DOC, despite a lower total soil carbon pool. These results suggest that altered hydrological and biogeochemical processes within the agricultural catchment, including accelerated soil erosion and soil organic matter turnover, contributed to an enhanced fluvial SS and carbon export. Thus, we argue that enhancing semi-natural vegetation within intensively farmed catchments could reduce sediment and carbon losses

  3. Using landscape typologies to model socioecological systems: Application to agriculture of the United States Gulf Coast

    DOE PAGESBeta

    Preston, Benjamin L.; King, Anthony Wayne; Mei, Rui; Nair, Sujithkumar Surendran

    2016-02-11

    Agricultural enterprises are vulnerable to the effects of climate variability and change. Improved understanding of the determinants of vulnerability and adaptive capacity in agricultural systems is important for projecting and managing future climate risk. At present, three analytical tools dominate methodological approaches to understanding agroecological vulnerability to climate: process-based crop models, empirical crop models, and integrated assessment models. A common weakness of these approaches is their limited treatment of socio-economic conditions and human agency in modeling agroecological processes and outcomes. This study proposes a framework that uses spatial cluster analysis to generate regional socioecological typologies that capture geographic variance inmore » regional agricultural production and enable attribution of that variance to climatic, topographic, edaphic, and socioeconomic components. This framework was applied to historical corn production (1986-2010) in the U.S. Gulf of Mexico region as a testbed. The results demonstrate that regional socioeconomic heterogeneity is an important driving force in human dominated ecosystems, which we hypothesize, is a function of the link between socioeconomic conditions and the adaptive capacity of agricultural systems. Meaningful representation of future agricultural responses to climate variability and change is contingent upon understanding interactions among biophysical conditions, socioeconomic conditions, and human agency their incorporation in predictive models.« less

  4. Comparison of the ranging behavior of Scotophilus kuhlii (Lesser Asiatic Yellow Bat) in agricultural and urban landscape

    NASA Astrophysics Data System (ADS)

    Atiqah, Nur; Akbar, Zubaid; Syafrinna, Ubaidah, Nur; Foo, Ng Yong

    2015-09-01

    Knowledge on home range sizes and movement patterns of animals through the environment is crucial for determining effects of habitat disturbance and fragmentation. To gauge the effects of land-use changes on Scotophilus kuhlii, a telemetric study was conducted between February 2014 and April 2014 in Tasik Chini, Pahang and Universiti Kebangsaan Malaysia (UKM), Bangi Campus. The home range sizes and movement patterns of S. kuhlii inhabiting agricultural landscape (Tasik Chini, Pahang) versus urban landscape (UKM) were compared. A total of ten individuals were successfully radio-tracked. Comparison of home range sizes of both sexes showed male S. kuhlii at Tasik Chini have larger mean home range sizes compared to UKM while female S.kuhlii in UKM have larger mean home range sizes compared to Tasik Chini. All individuals from both localities showed random movement. It is suggested that the home range and activity patterns might be influenced by food availability in the study area, food preferences and diet segregation and breeding behavior. This study provides baseline information on habitat utilization by S. kuhlii in relation to habitat perturbations.

  5. Landscape configuration is the primary driver of impacts on water quality associated with agricultural expansion

    NASA Astrophysics Data System (ADS)

    Chaplin-Kramer, Rebecca; Hamel, Perrine; Sharp, Richard; Kowal, Virgina; Wolny, Stacie; Sim, Sarah; Mueller, Carina

    2016-07-01

    Corporations and other multinational institutions are increasingly looking to evaluate their innovation and procurement decisions over a range of environmental criteria, including impacts on ecosystem services according to the spatial configuration of activities on the landscape. We have developed a spatially explicit approach and modeled a hypothetical corporate supply chain decision representing contrasting patterns of land-use change in four regions of the globe. This illustrates the effect of introducing spatial considerations in the analysis of ecosystem services, specifically sediment retention. We explored a wide variety of contexts (Iowa, USA; Mato Grosso, Brazil; and Jiangxi and Heilongjiang in China) and these show that per-area representation of impacts based on the physical characterization of a region can be misleading. We found two- to five-fold differences in sediment export for the same amount of habitat conversion within regions characterized by similar physical traits. These differences were mainly determined by the distance between land use changes and streams. The influence of landscape configuration is so dramatic that it can override wide variation in erosion potential driven by physical factors like soil type, slope, and climate. To minimize damage to spatially-dependent ecosystem services like water purification, sustainable sourcing strategies should not assume a direct correlation between impact and area but rather allow for possible nonlinearity in impacts, especially in regions with little remaining habitat and highly variable hydrological connectivity.

  6. Effects of lakes and reservoirs on annual river nitrogen, phosphorus, and sediment export in agricultural and forested landscapes

    USGS Publications Warehouse

    Powers, Steve M.; Robertson, Dale M.; Stanley, Emily H.

    2014-01-01

    Recently, effects of lakes and reservoirs on river nutrient export have been incorporated into landscape biogeochemical models. Because annual export varies with precipitation, there is a need to examine the biogeochemical role of lakes and reservoirs over time frames that incorporate interannual variability in precipitation. We examined long-term (~20 years) time series of river export (annual mass yield, Y, and flow-weighted mean annual concentration, C) for total nitrogen (TN), total phosphorus (TP), and total suspended sediment (TSS) from 54 catchments in Wisconsin, USA. Catchments were classified as small agricultural, large agricultural, and forested by use of a cluster analysis, and these varied in lentic coverage (percentage of catchment lake or reservoir water that was connected to river network). Mean annual export and interannual variability (CV) of export (for both Y and C) were higher in agricultural catchments relative to forested catchments for TP, TN, and TSS. In both agricultural and forested settings, mean and maximum annual TN yields were lower in the presence of lakes and reservoirs, suggesting lentic denitrification or N burial. There was also evidence of long-term lentic TP and TSS retention, especially when viewed in terms of maximum annual yield, suggesting sedimentation during high loading years. Lentic catchments had lower interannual variability in export. For TP and TSS, interannual variability in mass yield was often >50% higher than interannual variability in water yield, whereas TN variability more closely followed water (discharge) variability. Our results indicate that long-term mass export through rivers depends on interacting terrestrial, aquatic, and meteorological factors in which the presence of lakes and reservoirs can reduce the magnitude of export, stabilize interannual variability in export, as well as introduce export time lags.

  7. Comparison/Validation of Remote Sensing-Based Surface Energy Balance Models Over the Agricultural Landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Accurate characterization of surface energy fluxes over a range of spatial and temporal scales is critical for many applications in agriculture, hydrology, meteorology, and climatology. Over the past several years, there has been a major effort devoted to the development and refinement of remote sen...

  8. The Role of Hydropedologic Vegetation Zones in Greenhouse Gas Emissions for Agricultural Wetland Landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Net greenhouse gas (GHG) source strength for agricultural wetland ecosystems in the Prairie Pothole Region (PPR) and spatial constraints associated with CH4, CO2, and N2O fluxes are currently unknown. Greenhouse gas fluxes typically vary with edaphic, hydrologic, biologic, and climatic factors. In...

  9. Inundation influences on bioavailability of phosphorus in managed wetland sediments in agricultural landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural runoff carries high nutrient loads to receiving waters contributing to eutrophication. Managed wetlands can be used in integrated management efforts to intercept nutrients before they enter downstream aquatic systems, but detailed information regarding sorption and desorption of P by we...

  10. Innovative best management practices for improving nutrient reductions in agricultural landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As the burgeoning human population increases pressures on agriculture for increasing yields, the concomitant strain on the aquatic environment downstream is elevated through non-point source pollution. Traditional management practices of conservation tillage, terracing, and cover crops are good prac...

  11. Evaluation of the Precision Agricultural Landscape Modeling System (PALMS) in the Semiarid Texas Southern High Plains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Accurate models to simulate the soil water balance in semiarid cropping systems are needed to evaluate management practices for soil and water conservation in both irrigated and dryland production systems. The objective of this study was to evaluate the application of the Precision Agricultural Land...

  12. Application of nitrogen and phosphorus criteria for streams in agricultural landscapes.

    PubMed

    Chambers, P A; Benoy, G A; Brua, R B; Culp, J M

    2011-01-01

    Efforts to control eutrophication of water resources in agriculturally dominated ecosystems have focused on managing on-farm activities to reduce nutrient loss; however, another management measure for improving water quality is adoption of environmental performance criteria (or 'outcome-based standards'). Here, we review approaches for setting environmental quality criteria for nutrients, summarize approaches developed in Canada for setting 'ideal' and 'achievable' nutrient criteria for streams in agricultural watersheds, and consider how such criteria could be applied. As part of a 'National Agri-Environmental Standards Initiative', the Government of Canada committed to the development of non-regulatory environmental performance standards that establish total P (TP) and total N (TN) concentrations to protect ecological condition of agricultural streams. Application of four approaches for defining ideal standards using only chemistry data resulted in values for TP and TN spanning a relatively narrow range of concentrations within a given ecoregion. Cross-calibration of these chemically derived standards with information on biological condition resulted in recommendations for TP and TN that would likely protect aquatic life from adverse effects of eutrophication. Non-point source water quality modelling was then conducted in a specific watershed to estimate achievable standards, i.e. chemical conditions that could be attained using currently available and recommended management practices. Our research showed that, taken together, short-term achievable standards and ultimate ideal standards could be used to set policy targets that should, if realized, lower N and P concentrations in Canadian agricultural streams and improve biotic condition. PMID:22156121

  13. THE EFFECT OF CRANBERRY AGRICULTURE ON WETLAND LANDSCAPES, STREAM HYDROLOGY, AND AQUATIC COMMUNITIES

    EPA Science Inventory

    New Jersey contains about 3600 acres of cranberry bogs, and 70% of this acreage occurs within the 1470-km2 Mullica River basin. Cranberry agriculture occupied about 10,000 acres in 1920. Bog construction and management results in channelized stream segments, ditches, dikes, epi...

  14. Evaluation of the precision agricultural landscape modeling system (PALMS) in the semiarid Texas southern high plains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Accurate models to simulate the soil water balance in semiarid cropping systems are needed to evaluate management practices for soil and water conservation in both irrigated and dryland production systems. The objective of this study was to evaluate the application of the Precision Agricultural Land...

  15. Erosion processes by water in agricultural landscapes: a low-cost methodology for post-event analyses

    NASA Astrophysics Data System (ADS)

    Prosdocimi, Massimo; Calligaro, Simone; Sofia, Giulia; Tarolli, Paolo

    2015-04-01

    Throughout the world, agricultural landscapes assume a great importance, especially for supplying food and a livelihood. Among the land degradation phenomena, erosion processes caused by water are those that may most affect the benefits provided by agricultural lands and endanger people who work and live there. In particular, erosion processes that affect the banks of agricultural channels may cause the bank failure and represent, in this way, a severe threat to floodplain inhabitants and agricultural crops. Similarly, rills and gullies are critical soil erosion processes as well, because they bear upon the productivity of a farm and represent a cost that growers have to deal with. To estimate quantitatively soil losses due to bank erosion and rills processes, area based measurements of surface changes are necessary but, sometimes, they may be difficult to realize. In fact, surface changes due to short-term events have to be represented with fine resolution and their monitoring may entail too much money and time. The main objective of this work is to show the effectiveness of a user-friendly and low-cost technique that may even rely on smart-phones, for the post-event analyses of i) bank erosion affecting agricultural channels, and ii) rill processes occurring on an agricultural plot. Two case studies were selected and located in the Veneto floodplain (northeast Italy) and Marche countryside (central Italy), respectively. The work is based on high-resolution topographic data obtained by the emerging, low-cost photogrammetric method named Structure-from-Motion (SfM). Extensive photosets of the case studies were obtained using both standalone reflex digital cameras and smart-phone built-in cameras. Digital Terrain Models (DTMs) derived from SfM revealed to be effective to estimate quantitatively erosion volumes and, in the case of the bank eroded, deposited materials as well. SfM applied to pictures taken by smartphones is useful for the analysis of the topography

  16. Nitrate fate and transport through current and former depressional wetlands in an agricultural landscape, Choptank Watershed, Maryland, United States

    USGS Publications Warehouse

    Denver, J.M.; Ator, S.W.; Lang, M.W.; Fisher, T.R.; Gustafson, A.B.; Fox, R.; Clune, J.W.; McCarty, G.W.

    2014-01-01

    denitrification were limited, particularly where reducing conditions did not extend throughout the entire thickness of the surficial aquifer allowing NO3 to pass conservatively beneath a wetland along deeper groundwater flow paths. The complexity of N fate and transport associated with depressional wetlands complicates the understanding of their importance to water quality in adjacent streams. Although depressional wetlands often contribute low NO3 water to local streams, their effectiveness as landscape sinks, for N from adjacent agriculture varies with natural conditions, such as the thickness of the aquifer and the extent of reducing conditions. Measurement of such natural geologic, hydrologic, and geochemical conditions are therefore fundamental to understanding N mitigation in individual wetlands.

  17. Tightly-coupled plant-soil nitrogen cycling: Implications for multiple ecosystem services on organic farms across an intensively managed agricultural landscape

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Variability among farms across an agricultural landscape may reveal diverse biophysical contexts and experiences that show innovations and insights to improve nitrogen (N) cycling and yields, and thus the potential for multiple ecosystem services. In order to assess potential tradeoffs between yield...

  18. The importance of natural habitats to Brazilian free-tailed bats in intensive agricultural landscapes in the Winter Garden Region of Texas, United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The conversion of natural lands to agriculture affects the distribution of biological diversity across the landscape. In particular, cropland monocultures alter insect abundance and diversity compared to adjacent natural habitats, but nevertheless can provide large numbers of insect pests as prey i...

  19. Impact of land consolidation and field borders on soil erosion and storage within agricultural landscapes

    NASA Astrophysics Data System (ADS)

    Chartin, Caroline; Salvador-Blanes, Sébastien; Olivier, Evrard; Van Oost, Kristof; Hinschberger, Florent; Macaire, Jean-Jacques

    2014-05-01

    Soil erosion plays an important role in sediment and carbon storage within, and exports from, catchments. In cultivated landscapes, field borders can improve the temporary storage of eroded soil particles and associated carbon, by impeding lateral soil fluxes. These local soil accumulations can lead to the development of linear landforms (such as headlands and lynchets) which will keep evolving after field border removal. A recent study performed in a representative cultivated hillslope of the SW Parisian Basin showed that 39% of the area corresponds to landforms resulting from soil accumulation induced by former and present field borders. This study demonstrated that field borders influence greatly the landscape morphology, but also the spatial distribution of soil thickness, and locally the A-horizon thickness, which are essential parameters for the prediction of SOC stocks. This study aims at characterizing and quantifying the effect of field borders and their removal on medium term topsoil erosion and deposition rates in a cultivated hillslope of the SW Parisian Basin, consolidated in 1967. Here, we used the Cs-137 technique to assess recent patterns of soil redistribution. We measured the Cs-137 inventories of 68 soil cores sampled along transects covering the area and, more specifically, linear landforms identified along present and past field borders (i.e., lynchet and undulation landforms, respectively). Then, we used a spatially-distributed Cs-137 conversion model that simulates and discriminates soil redistribution induced by water and tillage erosion processes over the last fifty years. Finally, observations and model outputs were confronted. Our results show that tillage erosion dominate the soil redistribution in the study area for the 1954-2009 period and generated about 95% (i.e., 4.50 Mg.ha-1.yr-1) of the total gross erosion. Soil redistribution was largely affected by the presence of current and former field borders, where hotspots areas of

  20. Pre-Columbian agricultural landscapes, ecosystem engineers, and self-organized patchiness in Amazonia

    PubMed Central

    McKey, Doyle; Rostain, Stéphen; Iriarte, José; Glaser, Bruno; Birk, Jago Jonathan; Holst, Irene; Renard, Delphine

    2010-01-01

    The scale and nature of pre-Columbian human impacts in Amazonia are currently hotly debated. Whereas pre-Columbian people dramatically changed the distribution and abundance of species and habitats in some parts of Amazonia, their impact in other parts is less clear. Pioneer research asked whether their effects reached even further, changing how ecosystems function, but few in-depth studies have examined mechanisms underpinning the resilience of these modifications. Combining archeology, archeobotany, paleoecology, soil science, ecology, and aerial imagery, we show that pre-Columbian farmers of the Guianas coast constructed large raised-field complexes, growing on them crops including maize, manioc, and squash. Farmers created physical and biogeochemical heterogeneity in flat, marshy environments by constructing raised fields. When these fields were later abandoned, the mosaic of well-drained islands in the flooded matrix set in motion self-organizing processes driven by ecosystem engineers (ants, termites, earthworms, and woody plants) that occur preferentially on abandoned raised fields. Today, feedbacks generated by these ecosystem engineers maintain the human-initiated concentration of resources in these structures. Engineer organisms transport materials to abandoned raised fields and modify the structure and composition of their soils, reducing erodibility. The profound alteration of ecosystem functioning in these landscapes coconstructed by humans and nature has important implications for understanding Amazonian history and biodiversity. Furthermore, these landscapes show how sustainability of food-production systems can be enhanced by engineering into them fallows that maintain ecosystem services and biodiversity. Like anthropogenic dark earths in forested Amazonia, these self-organizing ecosystems illustrate the ecological complexity of the legacy of pre-Columbian land use. PMID:20385814

  1. Importance of agricultural landscapes to nesting burrowing owls in the Northern Great Plains, USA

    USGS Publications Warehouse

    Restani, M.; Davies, J.M.; Newton, W.E.

    2008-01-01

    Anthropogenic habitat loss and fragmentation are the principle factors causing declines of grassland birds. Declines in burrowing owl (Athene cunicularia) populations have been extensive and have been linked to habitat loss, primarily the decline of black-tailed prairie dog (Cynomys ludovicianus) colonies. Development of habitat use models is a research priority and will aid conservation of owls inhabiting human-altered landscapes. From 2001 to 2004 we located 160 burrowing owl nests on prairie dog colonies on the Little Missouri National Grassland in North Dakota. We used multiple linear regression and Akaike's Information Criterion to estimate the relationship between cover type characteristics surrounding prairie dog colonies and (1) number of owl pairs per colony and (2) reproductive success. Models were developed for two spatial scales, within 600 m and 2,000 m radii of nests for cropland, crested wheatgrass (Agropyron cristatum), grassland, and prairie dog colonies. We also included number of patches as a metric of landscape fragmentation. Annually, fewer than 30% of prairie dog colonies were occupied by owls. None of the models at the 600 m scale explained variation in number of owl pairs or reproductive success. However, models at the 2,000 m scale did explain number of owl pairs and reproductive success. Models included cropland, crested wheatgrass, and prairie dog colonies. Grasslands were not included in any of the models and had low importance values, although percentage grassland surrounding colonies was high. Management that protects prairie dog colonies bordering cropland and crested wheatgrass should be implemented to maintain nesting habitat of burrowing owls. ?? 2008 Springer Science+Business Media B.V.

  2. A small-scale land-sparing approach to conserving biological diversity in tropical agricultural landscapes.

    PubMed

    Chandler, Richard B; King, David I; Raudales, Raul; Trubey, Richard; Chandler, Carlin; Chávez, Víctor Julio Arce

    2013-08-01

    Two contrasting strategies have been proposed for conserving biological diversity while meeting the increasing demand for agricultural products: land sparing and land sharing production systems. Land sparing involves increasing yield to reduce the amount of land needed for agriculture, whereas land-sharing agricultural practices incorporate elements of native ecosystems into the production system itself. Although the conservation value of these systems has been extensively debated, empirical studies are lacking. We compared bird communities in shade coffee, a widely practiced land-sharing system in which shade trees are maintained within the coffee plantation, with bird communities in a novel, small-scale, land-sparing coffee-production system (integrated open canopy or IOC coffee) in which farmers obtain higher yields under little or no shade while conserving an area of forest equal to the area under cultivation. Species richness and diversity of forest-dependent birds were higher in the IOC coffee farms than in the shade coffee farms, and community composition was more similar between IOC coffee and primary forest than between shade coffee and primary forest. Our study represents the first empirical comparison of well-defined land sparing and land sharing production systems. Because IOC coffee farms can be established by allowing forest to regenerate on degraded land, widespread adoption of this system could lead to substantial increases in forest cover and carbon sequestration without compromising agricultural yield or threatening the livelihoods of traditional small farmers. However, we studied small farms (<5 ha); thus, our results may not generalize to large-scale land-sharing systems. Furthermore, rather than concluding that land sparing is generally superior to land sharing, we suggest that the optimal approach depends on the crop, local climate, and existing land-use patterns. PMID:23551570

  3. Evapotranspiration and surface energy balance across an agricultural-urban landscape gradient in Southern California, USA.

    NASA Astrophysics Data System (ADS)

    Shiflett, S. A.; Anderson, R. G.; Jenerette, D.

    2014-12-01

    Urbanization substantially affects energy, surface and air temperature, and hydrology due to extensive modifications in land surface properties such as vegetation, albedo, thermal capacity and soil moisture. The magnitude and direction of these alterations depends heavily on the type of urbanization that occurs. We investigated energy balance variation in a local network of agricultural and urban ecosystems using the eddy covariance method to better understand how vegetation fraction and degree of urbanization affects energy exchanges between the land surface and the atmosphere. We deployed eddy flux systems within a well-irrigated, agricultural citrus orchard, a moderately developed urban zone with a substantial amount of local vegetative cover, and an intensely developed urban zone with minimal vegetative cover and increased impervious surfaces relative to the other two sites. Latent energy (LE) fluxes in the agricultural area ranged from 7.9 ± 1.4 W m-2 (nighttime) to 168.7 ± 6.2 W m-2 (daytime) compared to 10.2 ± 3.5 W m-2 and 40.6 ± 4.1 W m-2, respectively, for the moderately developed urban area. Sensible energy (H) fluxes ranged from -9.1 ± 1.0 W m-2 (nighttime) to 119 ± 7.0 W m-2 (daytime) in the agricultural area compared to 9.6 ± 2.6 W m-2 and 134 ± 6.0 W m-2, respectively, for the moderately developed urban zone. Daytime LE is reduced with increasing urbanization; however, daily cycles of LE are less recognizable in urban areas compared to distinct daily cycles obtained above a mature citrus crop. In contrast, both daytime and nighttime H increases with increasing degree of urbanization. Reduction in vegetation and increases in impervious surfaces along an urbanization gradient leads to alterations in energy balance, which are associated with microclimate and water use changes.

  4. Prevalence of conservation design in an agriculture-dominated landscape: the case of Northern Indiana.

    PubMed

    Crick, Julie; Prokopy, Linda Stalker

    2009-06-01

    We examined the prevalence of residential development that occurs with consideration of the natural features of the site, known as conservation design, within county-level planning jurisdictions across Northern Indiana. Using data from telephone interviews with representatives of planning departments, jurisdictions were ranked based on reported use of conservation design. Three categories of use emerged from the data: no use, use of individual practices associated with conservation design, and integration of multiple conservation design practices. Qualitative data analysis revealed that conservation design practices were not being used widely and, when used, were often used to fulfill stormwater requirements. Statistical analysis, using data from interviews, spatial data sets, and the U.S. Census Bureau, identified several significant positive predictors of the levels of conservation design use including conversion of forest or agricultural land cover to urban uses and education levels in the jurisdiction. Many of the interviewees noted that agricultural land is perceived to meet open space needs within their counties. Given that agricultural land does not fully meet all ecosystem needs, education about the benefits of other types of open space is suggested. PMID:19224272

  5. Classification of crops across heterogeneous agricultural landscape in Kenya using AisaEAGLE imaging spectroscopy data

    NASA Astrophysics Data System (ADS)

    Piiroinen, Rami; Heiskanen, Janne; Mõttus, Matti; Pellikka, Petri

    2015-07-01

    Land use practices are changing at a fast pace in the tropics. In sub-Saharan Africa forests, woodlands and bushlands are being transformed for agricultural use to produce food for the rapidly growing population. The objective of this study was to assess the prospects of mapping the common agricultural crops in highly heterogeneous study area in south-eastern Kenya using high spatial and spectral resolution AisaEAGLE imaging spectroscopy data. Minimum noise fraction transformation was used to pack the coherent information in smaller set of bands and the data was classified with support vector machine (SVM) algorithm. A total of 35 plant species were mapped in the field and seven most dominant ones were used as classification targets. Five of the targets were agricultural crops. The overall accuracy (OA) for the classification was 90.8%. To assess the possibility of excluding the remaining 28 plant species from the classification results, 10 different probability thresholds (PT) were tried with SVM. The impact of PT was assessed with validation polygons of all 35 mapped plant species. The results showed that while PT was increased more pixels were excluded from non-target polygons than from the polygons of the seven classification targets. This increased the OA and reduced salt-and-pepper effects in the classification results. Very high spatial resolution imagery and pixel-based classification approach worked well with small targets such as maize while there was mixing of classes on the sides of the tree crowns.

  6. Prevalence of Conservation Design in an Agriculture-Dominated Landscape: The Case of Northern Indiana

    NASA Astrophysics Data System (ADS)

    Crick, Julie; Prokopy, Linda Stalker

    2009-06-01

    We examined the prevalence of residential development that occurs with consideration of the natural features of the site, known as conservation design, within county-level planning jurisdictions across Northern Indiana. Using data from telephone interviews with representatives of planning departments, jurisdictions were ranked based on reported use of conservation design. Three categories of use emerged from the data: no use, use of individual practices associated with conservation design, and integration of multiple conservation design practices. Qualitative data analysis revealed that conservation design practices were not being used widely and, when used, were often used to fulfill stormwater requirements. Statistical analysis, using data from interviews, spatial data sets, and the U.S. Census Bureau, identified several significant positive predictors of the levels of conservation design use including conversion of forest or agricultural land cover to urban uses and education levels in the jurisdiction. Many of the interviewees noted that agricultural land is perceived to meet open space needs within their counties. Given that agricultural land does not fully meet all ecosystem needs, education about the benefits of other types of open space is suggested.

  7. Impact of the Spatial Arrangement of Agricultural Land Use on Ecosystems Services and Peri-Urban Livelihoods at the Landscape Scale.

    NASA Astrophysics Data System (ADS)

    Inkoom, J. N.; Fürst, C.

    2014-12-01

    The relationship between agricultural land uses (ALU) and their impact on ecosystems services (ES) including biodiversity conservation is complex. This complexity has been augmented by isolated research on the impact of ALU on the landscape's capacity to provide ES in most climatically vulnerable areas of Sub-Saharan Africa. Though a considerable number of studies emphasise the nexus between specific land use types and their impact on ES, a sufficient modelling basis for an empirical consideration of spatial interactions between different agricultural land uses at the landscape scale within peri-urban areas in Sub-Saharan Africa is consistently missing. The need to assess and address significant issues regarding size, shape, spatial location, and interactivity of different land use patches in assessing land use interactions and their impact on ecosystem service provision necessitated this investigation. To formulate a methodology to correspond to this complexity, ES obtained from a characteristically agricultural and urbanizing landscapes were mapped using analytical hierarchical processes and management expert approaches. Further, landscape metrics and mean enrichment factor approaches are explored as neighbourhood assessment tools aimed at assessing the mutual impact gradient of agricultural and adjacent urban land uses on ES provision. Implementation is undertaken in GISCAME using a 2012 rapideye image classification and primary data collected on selected ES from local farmers within the VEA catchment of Upper East, Ghana. The outcome aims to provide the understanding of expected trade-offs and synergies varying ALU could pose to current and potential ES provision within urbanizing landscapes. Policy implications for observed trade-offs and synergies of ALU interaction on ES, rural livelihoods, and food security are communicated to farmers and decision makers. Keywords: Agricultural land use, neighbourhood interaction, ecosystems services, livelihoods, GISCAME.

  8. Geomorphic response to agricultural land use in small fluvial systems - The role of landscape connectivity

    NASA Astrophysics Data System (ADS)

    Poeppl, R.; Keiler, M.; Glade, T.; Engage-Geomorphological Systems; Risk Research

    2010-12-01

    Nearly all river catchments are affected directly or indirectly by human actions, e.g. varying agricultural land use or interventions into to river course and flow lead to significant geomorphic changes. The rates of fluvial change are accelerating in many river catchments and public and institutional awareness of these changes and their consequences has grown. This trend leads to an increasing need for a deeper understanding of how the system elements are interrelated (connected) and how fluvial systems respond to human activities. Most of the studies relating to such topics focus on extrinsic (e.g. climatic) factors, although vegetation cover is one of the primary intrinsic factors on sediment yield to a river and even the most susceptible factor for human alterations. Furthermore, nearly all of the published studies are dealing with large rivers, disregarding the much more abundant smaller ones, which in sum do also influence larger rivers. The presented study contributes to gain a deeper understanding of how river systems geomorphologically respond to human activities. The focus in this study is on the importance of hillslope-channel connectivity relationships, as well as on connectivity relationships between the channel reaches in catchments with agricultural land use. Therefore, aerial photograph and airborne laserscan-interpretations were used to create detailed land use and river maps in order to gather current land use and river planform geometry conditions. The land use data was integrated to a GIS-related spatial soil erosion model so as to determine sources of fine sediment from eroding top soil in agricultural areas. Furthermore, a DEM-based multiple-flow model was applied to examine hillslope-channel connectivity relationships. River bed sediment composition, sediment embeddedness and in-channel accumulation of fine sediments were surveyed as potential indicators for geomorphic system response to agricultural land-use, as well as to determine

  9. A Methodological Approach for Spatiotemporally Analyzing Water-Polluting Effluents in Agricultural Landscapes Using Partial Triadic Analysis.

    PubMed

    Jiménez, J J; Darwiche-Criado, N; Sorando, R; Comín, F A; Sánchez-Pérez, J M

    2015-09-01

    Multivariate techniques for two-dimensional data matrices are normally used in water quality studies. However, if the temporal dimension is included in the analysis, other statistical techniques are recommended. In this study, partial triadic analysis was used to investigate the spatial and temporal variability in water quality variables sampled in a northeastern Spain river basin. The results highlight the spatiality of the physical and chemical properties of water at different sites along a river over 1 yr. Partial triadic analysis allowed us to clearly identify the presence of a stable spatial structure that was common to all sampling dates across the entire catchment. Variables such as electrical conductivity and Na and Cl ions were associated with agricultural sources, whereas total dissolved nitrogen, NH-N concentrations, and NO-N concentrations were linked to polluted urban sites; differences were observed between irrigated and nonirrigated periods. The concentration of NO-N was associated with both agricultural and urban land uses. Variables associated with urban and agricultural pollution sources were highly influenced by the seasonality of different activities conducted in the study area. In analyzing the impact of land use and fertilization management on water runoff and effluents, powerful statistical tools that can properly identify the causes of pollution in watersheds are important. Partial triadic analysis can efficiently summarize site-specific water chemistry patterns in an applied setting for land- and water-monitoring schemes at the landscape level. The method is recommended for land-use decision-making processes to reduce harmful environmental effects and promote sustainable watershed management. PMID:26436278

  10. Woodchip bioreactors for N-source reduction in a highly managed agricultural landscape

    NASA Astrophysics Data System (ADS)

    Kult, K.; Jones, C. S.

    2011-12-01

    Excess nutrification and the resulting hypoxia in the Gulf of Mexico are increasingly understood to originate in managed landscapes of the Upper Mississippi River basin. Nitrogen inputs to cropped fields are high in landscapes with soils containing high organic nitrogen content that, when mineralized, releases nitrogen in the soluble nitrate form. These in situ sources supply extensive subsurface drainage systems that rapidly transport nitrogen to streams and ultimately the Gulf. Aggressive in-field N management can reduce loading to streams, but will not reduce loads to sufficiently impact Gulf hypoxia. Edge of Field (EOF) treatment will be needed to reach water quality objectives. Denitrification bioreactors are one technology being studied for practical and economical EOF nitrate reduction. Bioreactors intercept the high-N tile-drain effluent with woodchip substrates that provide carbon and energy to support denitrification. Iowa Soybean Association (ISA) installed six bioreactors. Design of the ISA bioreactors has focused on the diameter of the field tile and the catchment area. Designs balance discharge with retention times. The bioreactors have been designed to have a 4-hour hydraulic retention time (HRT) capable of treating 20% of peak flow. Denitrification is assumed to follow zero-order kinetics given the high NO3 concentrations in the studied systems. Aerobic organisms must deplete DO sufficiently so anaerobic denitrifying organisms can compete. Insufficient HRT results in unsatisfactory NO3 reductions. Conditions favoring incomplete denitrification can lead to emission of the greenhouse gas N2O. Excessive retention times allow for complete denitrification enabling SO4-reducing bacteria to thrive. This produces undesirable results: conversion of SO4 to H2S, C-source depletion, production of toxic CH3Hg+, and methanogenesis. A flow control structure (FCS) allows for management of HRT by modifying the position of stop logs. Increased HRT reduces the amount

  11. Sampling network stratification by terrain classification in eroded agricultural landscapes at plot scale

    NASA Astrophysics Data System (ADS)

    Penížek, Vít; Zádorová, Tereza; Kodešová, Radka

    2015-04-01

    The description of soil properties variability is important aspect in land management and food production at plot scale. We describe novelty approach for design of sampling network on agricultural plots with high relief variability. The terrain properties were used for improved spatial prediction of soil properties including design of the sampling network. Regular sampling network, random sampling network, systematic unaligned sampling network and stratified sampling network schemes were compared to prove the advantages of relief based stratified sampling networks. The study was performed for humus horizon depth prediction on agriculture plot of 6.5 ha with dissected relief where originally homogenous soil cover was differentiated by erosion and sedimentation into mosaic of Chernozem, Regosol and colluvial soils. Moreover the comparison was done on three levels of sampling density (65, 40 and 24 sampling points). The stratification of sampling network was based on unsupervised relief classification. The performance of the soil properties prediction based on different sampling network was assesed by RMSE calculation based on predicted values versus validation dataset. According the RMSE, the stratified sampling network performed the best (7.4 cm) comparing the regular sampling network (10.8 cm), random sampling network (17.7 cm) and systematic unaligned sampling network (11.2 cm). The accuracy of the soil properties spatial prediction decreased with the decreasing number of sampling points, but the stratified network performed significantly better that other used methods. The study showed that, for soil properties spatial variability description at certain accuracy level, relief-based stratified network can contain 25 % less sampling points comparing to regular network. This leads to potential financial and person cost reduction for the soil survey. The study was supported by grant nr. 13-07516P of the Czech science foundation and by grant nr. QJ1230319 of the

  12. Data on four criteria for targeting the placement of conservation buffers in agricultural landscapes

    PubMed Central

    Qiu, Zeyuan; Dosskey, Michael G.; Kang, Yang

    2016-01-01

    Four criteria are generally used to prioritize agricultural lands for placing conservation buffers. The criteria include soil erodibility, hydrological sensitivity, wildlife habitat, and impervious surface rate that capture conservation buffers’ benefits in reducing soil erosion, controlling runoff generation, enhancing wildlife habitat, and mitigating stormwater impacts, respectively. This article describes the data used to derive the values of those attributes and a scheme to classify the values in multi-criteria analysis of conservation buffer placement in “Choosing between alternative placement strategies for conservation buffers using borda count” [1]. PMID:27222843

  13. Data on four criteria for targeting the placement of conservation buffers in agricultural landscapes.

    PubMed

    Qiu, Zeyuan; Dosskey, Michael G; Kang, Yang

    2016-06-01

    Four criteria are generally used to prioritize agricultural lands for placing conservation buffers. The criteria include soil erodibility, hydrological sensitivity, wildlife habitat, and impervious surface rate that capture conservation buffers' benefits in reducing soil erosion, controlling runoff generation, enhancing wildlife habitat, and mitigating stormwater impacts, respectively. This article describes the data used to derive the values of those attributes and a scheme to classify the values in multi-criteria analysis of conservation buffer placement in "Choosing between alternative placement strategies for conservation buffers using borda count" [1]. PMID:27222843

  14. Agricultural peat lands; towards a greenhouse gas sink - a synthesis of a Dutch landscape study

    NASA Astrophysics Data System (ADS)

    Schrier-Uijl, A. P.; Kroon, P. S.; Hendriks, D. M. D.; Hensen, A.; Van Huissteden, J. C.; Leffelaar, P. A.; Berendse, F.; Veenendaal, E. M.

    2013-06-01

    It is generally known that managed, drained peatlands act as carbon sources. In this study we examined how mitigation through the reduction of management and through rewetting may affect the greenhouse gas (GHG) emission and the carbon balance of intensively managed, drained, agricultural peatlands. Carbon and GHG balances were determined for three peatlands in the western part of the Netherlands from 2005 to 2008 by considering spatial and temporal variability of emissions (CO2, CH4 and N2O). One area (Oukoop) is an intensively managed grass-on-peatland, including a dairy farm, with the ground water level at an average annual depth of 0.55 m below the soil surface. The second area (Stein) is an extensively managed grass-on-peatland, formerly intensively managed, with a dynamic ground water level at an average annual depth of 0.45 m below the soil surface. The third area is an (since 1998) rewetted former agricultural peatland (Horstermeer), close to Oukoop and Stein, with the average annual ground water level at a depth of 0.2 m below the soil surface. During the measurement campaigns we found that both agriculturally managed sites acted as carbon and GHG sources but the rewetted agricultural peatland acted as a carbon and GHG sink. The terrestrial GHG source strength was 1.4 kg CO2-eq m-2 yr-1 for the intensively managed area and 1.0 kg CO2-eq m-2 yr-1 for the extensively managed area; the unmanaged area acted as a GHG sink of 0.7 kg CO2-eq m-2 yr-1. Water bodies contributed significantly to the terrestrial GHG balance because of a high release of CH4 and the loss of DOC only played a minor role. Adding the farm-based CO2 and CH4 emissions increased the source strength for the managed sites to 2.7 kg CO2-eq m-2 yr-1 for Oukoop and 2.1 kg CO2-eq m-2 yr-1 for Stein. Shifting from intensively managed to extensively managed grass-on-peat reduced GHG emissions mainly because N2O emission and farm-based CH4 emissions decreased. Overall, this study suggests that managed

  15. Agriculture at the Edge: Landscape Variability of Soil C Stocks and Fluxes in the Tropical Andes

    NASA Astrophysics Data System (ADS)

    Riveros-Iregui, D. A.; Peña, C.

    2015-12-01

    Paramos, or tropical alpine grasslands occurring right above the forest tree-line (2,800 - 4,700 m), are among the most transformed landscapes in the humid tropics. In the Tropical Andes, Paramos form an archipelago-like pattern from Northern Colombia to Central Peru that effectively captures atmospheric moisture originated in the Amazon-Orinoco basins, while marking the highest altitude capable of sustaining vegetation growth (i.e., 'the edge'). This study investigates the role of land management on mediating soil carbon stocks and fluxes in Paramo ecosystems of the Eastern Cordillera of Colombia. Observations were collected at a Paramo site strongly modified by land use change, including active potato plantations, pasture, tillage, and land abandonment. Results show that undisturbed Paramos soils have high total organic carbon (TOC), high soil water content (SWC), and low soil CO2 efflux (RS) rates. However, Paramo soils that experience human intervention show lower TOC, higher and more variable RS rates, and lower SWC. This study demonstrates that changes in land use in Paramos affect differentially the accumulation and exchange of soil carbon with the atmosphere and offers implications for management and protection strategies of what has been deemed the fastest evolving biodiversity ecosystem in the world.

  16. Farm nitrogen balances in six European agricultural landscapes - a method for farming system assessment, emission hotspot identification, and mitigation measure evaluation

    NASA Astrophysics Data System (ADS)

    Dalgaard, T.; Bienkowski, J. F.; Bleeker, A.; Drouet, J. L.; Durand, P.; Dragosits, U.; Frumau, A.; Hutchings, N. J.; Kedziora, A.; Magliulo, V.; Olesen, J. E.; Theobald, M. R.; Maury, O.; Akkal, N.; Cellier, P.

    2012-07-01

    Six agricultural landscapes in Poland (PL), the Netherlands (NL), France (FR), Italy (IT), Scotland (UK) and Denmark (DK) were studied, and a common method was developed for undertaking farm inventories and the derivation of farm nitrogen (N) balances and N surplus from the in total 222 farms and 11 440 ha of farmland. In all landscapes, a large variation in the farm N surplus was found, and thereby a large potential for reductions. The highest average N surpluses were found in the most livestock-intensive landscapes of IT, FR, and NL; on average 202 ± 28, 179 ± 63 and 178 ± 20 kg N ha-1yr-1, respectively. However, all landscapes showed hotspots, especially from livestock farms, including a special UK case with landless large-scale poultry farming. So, whereas the average N surplus from the land-based UK farms dominated by extensive sheep grazing was only 31 ± 10 kg N ha-1yr-1, the landscape average was similar to those of PL and DK (122 ± 20 and 146 ± 55 kg N ha-1yr-1, respectively) when landless poultry were included. However, the challenge remains how to account for indirect N surpluses and emissions from such farms with a large export of manure out of the landscape. We conclude that farm N balances are a useful indicator for N losses and the potential for improving N management. Significant correlations to N surplus were found, both with ammonia air concentrations and nitrate levels in soils and groundwater, measured during the landscape data collection campaign from 2007-2009. This indicates that farm N surpluses may be used as an independent dataset for validation of measured and modelled N emissions in agricultural landscapes. However, no significant correlation was found to N measured in surface waters, probably because of the short time horizon of the study. A case study of the development in N surplus from the landscape in DK from 1998-2008 showed a 22 % reduction, related to statistically significant effects (p < 0.01) of measures targeted at

  17. Riparian strip efficiency assessment in agricultural landscapes using stereoscopic very high spatial resolution satellite imagery

    NASA Astrophysics Data System (ADS)

    Chokmani, Karem; Novoa, Julio

    2015-04-01

    Riparian strips are used worldwide to protect riverbanks and water quality in agricultural zones because of their several environmental benefits. A metric called the Riparian Strip Quality Index, which is based on the percentage area of riverine vegetation found on the riparian strip, is used to evaluate their ecological condition. This index could be considered an indicator of the potential capacity of riparian strips to filter sediments, retain pollutants, and provide shelter to terrestrial and aquatic species. Thus, in order to know if a riparian strip is truly efficient in agricultural lands, which means that it is fulfilling those ecological functions, it is necessary to understand their ability to intercept surface runoff. The latter is the major cause of water pollution and erosion in these productive areas. Besides vegetation coverage, topographic and hydrologic parameters must be included to model the intensity and spatial distribution of runoff streamflow at local scales. The geospatial information used to assess the ecological efficiency of riparian strips was extracted from very-high-spatial-resolution WorldView-2 satellite imagery. This information was then processed using current geospatial techniques such as object-based image analysis and was used to develop a Riparian Strip Efficiency Index. The results show that this index might be used to assess the efficiency of riparian strips, which will enable land managers to monitor changes occurring over time, identify priority areas for restoration activities. This, in turn, might ensure optimal allocation of private or public funds towards the most inefficient and threatened riparian strips.

  18. Spatial variation analyses of Thematic Mapper data for the identification of linear features in agricultural landscapes

    NASA Technical Reports Server (NTRS)

    Pelletier, R. E.

    1984-01-01

    A need exists for digitized information pertaining to linear features such as roads, streams, water bodies and agricultural field boundaries as component parts of a data base. For many areas where this data may not yet exist or is in need of updating, these features may be extracted from remotely sensed digital data. This paper examines two approaches for identifying linear features, one utilizing raw data and the other classified data. Each approach uses a series of data enhancement procedures including derivation of standard deviation values, principal component analysis and filtering procedures using a high-pass window matrix. Just as certain bands better classify different land covers, so too do these bands exhibit high spectral contrast by which boundaries between land covers can be delineated. A few applications for this kind of data are briefly discussed, including its potential in a Universal Soil Loss Equation Model.

  19. Agricultural peatlands: towards a greenhouse gas sink - a synthesis of a Dutch landscape study

    NASA Astrophysics Data System (ADS)

    Schrier-Uijl, A. P.; Kroon, P. S.; Hendriks, D. M. D.; Hensen, A.; Van Huissteden, J.; Berendse, F.; Veenendaal, E. M.

    2014-08-01

    It is generally known that managed, drained peatlands act as carbon (C) sources. In this study we examined how mitigation through the reduction of the intensity of land management and through rewetting may affect the greenhouse gas (GHG) emission and the C balance of intensively managed, drained, agricultural peatlands. Carbon and GHG balances were determined for three peatlands in the western part of the Netherlands from 2005 to 2008 by considering spatial and temporal variability of emissions (CO2, CH4 and N2O). One area (Oukoop) is an intensively managed grass-on-peatland area, including a dairy farm, with the ground water level at an average annual depth of 0.55 (±0.37) m below the soil surface. The second area (Stein) is an extensively managed grass-on-peatland area, formerly intensively managed, with a dynamic ground water level at an average annual depth of 0.45 (±0.35) m below the soil surface. The third area is a (since 1998) rewetted former agricultural peatland (Horstermeer), close to Oukoop and Stein, with the average annual ground water level at a depth of 0.2 (±0.20) m below the soil surface. During the measurement campaigns we found that both agriculturally managed sites acted as C and GHG sources and the rewetted former agricultural peatland acted as a C and GHG sink. The ecosystem (fields and ditches) total GHG balance, including CO2, CH4 and N2O, amounted to 3.9 (±0.4), 1.3 (±0.5) and -1.7 (±1.8) g CO2-eq m-2 d-1 for Oukoop, Stein and Horstermeer, respectively. Adding the farm-based emissions to Oukoop and Stein resulted in a total GHG emission of 8.3 (±1.0) and 6.6 (±1.3) g CO2-eq m-2 d-1, respectively. For Horstermeer the GHG balance remained the same since no farm-based emissions exist. Considering the C balance (uncertainty range 40-60%), the total C release in Oukoop and Stein is 5270 and 6258 kg C ha-1 yr-1, respectively (including ecosystem and management fluxes), and the total C uptake in Horstermeer is 3538 kg C ha-1 yr-1. Water

  20. Monitoring roadside ditches for antibiotic resistant E. coli in forest and agricultural landscapes

    NASA Astrophysics Data System (ADS)

    Storrer, S.; Archibald, J. A.

    2009-12-01

    There is growing concern over the threat of antibiotic resistant bacteria and how they travel through natural environments. This study was developed to: (1) measure the quantities of antibiotic resistant Escherichia coli present in stormwater collected from roadside ditches, (2) examine the spatial and temporal distribution of antibiotic resistance and (3) explore the difference in antibiotic resistance between different land uses. Autosamplers were used to collect composite samples of stormwater flowing in roadside ditches located near manure fertilized fields or forested areas. Samples were filtered using standard membrane filtration methods and grown with and without antibiotics on EC medium containing MUG. Three antibiotics commonly used to treat infection in humans and dairy cows were used to measure antibiotic resistance: penicillin, ampicillin and tetracycline. Though antibiotic resistance was found at forested and farm sites, preliminary data suggest higher counts of antibiotic resistant E. coli near agricultural areas.

  1. Socioeconomic Dimensions of Changes in the Agricultural Landscape of the Mediterranean Basin: A Case Study of the Abandonment of Cultivation Terraces on Nisyros Island, Greece

    NASA Astrophysics Data System (ADS)

    Petanidou, Theodora; Kizos, Thanasis; Soulakellis, Nikolaos

    2008-02-01

    Agricultural landscapes illustrate the impact of human actions on physical settings, and differential human pressures cause these landscapes to change with time. Our study explored changes in the terraced landscapes of Nisyros Island, Greece, focusing on the socioeconomic aspects during two time periods using field data, cadastral research, local documents, and published literature, as well as surveys of the islanders. Population increases during the late 19th to early 20th centuries marked a significant escalation of terrace and dry stone wall construction, which facilitated cultivation on 58.4% of the island. By the mid-20th century, the economic collapse of agricultural activities and consequent emigration caused the abandonment of cultivated land and traditional management practices, dramatically reducing farm and field numbers. Terrace abandonment continued in recent decades, with increased livestock grazing becoming the main land management tool; as a result, both farm and pasture sizes increased. Neglect and changing land use has led to deterioration and destruction of many terraces on the island. We discuss the socioeconomic and political backgrounds responsible for the land-use change before World War II (annexation of Nisyros Island by the Ottoman Empire, Italy, and Greece; overseas migration opportunities; and world transportation changes) and after the war (social changes in peasant societies; worldwide changes in agricultural production practices). The adverse landscape changes documented for Nisyros Island appear to be inevitable for modern Mediterranean rural societies, including those on other islands in this region. The island’s unique terraced landscapes may qualify Nisyros to become an archive or repository of old agricultural management techniques to be used by future generations and a living resource for sustainable management.

  2. Maximizing the wildlife conservation value of road right-of-ways in an agriculturally dominated landscape.

    PubMed

    McCleery, Robert A; Holdorf, Allison R; Hubbard, Laura L; Peer, Brian D

    2015-01-01

    There has been a growing recognition that the narrow linear strips of uncultivated vegetation that lie between roads and agricultural crops, referred to as roadside right-of-ways or verges, can serve as areas for the conservation of wildlife. The features of right-of-ways that should influence the composition of wildlife communities vary considerably. Our goal was to determine what features of right-of-ways increased the conservation potential of right-of-ways for wildlife in a grassland system dominated by agricultural production. We sampled 100 right-of-ways for birds and 92 right-of-ways for small mammals in McDonough and Warren Counties in west-central Illinois. We found that the sizes of right-of-ways and the amount of traffic on the adjacent roads synergistically worked to influence wildlife communities. On roads with low traffic, avian species richness increased rapidly with increased right-of-way width, while on roads with high traffic, avian richness increased only slightly with increasing right-of-way widths. We found that wider roadside right-of-ways (preferably across the road from equally wide right-of-ways) with thicker and taller vegetation had the greatest conservation value for birds and small mammals. The features that enhanced the conservation value of right-of-ways in our study area were uncommon. Efforts to create or enhance these features for the benefit of wildlife would likely face numerous obstacles. Nonetheless, from a grassland conservation perspective, working with stakeholders to implement specific strategies to enhance these often neglected areas may be an effective complement to purchasing and restoring conservation lands away from roads. PMID:25794180

  3. Maximizing the Wildlife Conservation Value of Road Right-of-Ways in an Agriculturally Dominated Landscape

    PubMed Central

    McCleery, Robert A.; Holdorf, Allison R.; Hubbard, Laura L.; Peer, Brian D.

    2015-01-01

    There has been a growing recognition that the narrow linear strips of uncultivated vegetation that lie between roads and agricultural crops, referred to as roadside right-of-ways or verges, can serve as areas for the conservation of wildlife. The features of right-of-ways that should influence the composition of wildlife communities vary considerably. Our goal was to determine what features of right-of-ways increased the conservation potential of right-of-ways for wildlife in a grassland system dominated by agricultural production. We sampled 100 right-of-ways for birds and 92 right-of-ways for small mammals in McDonough and Warren Counties in west-central Illinois. We found that the sizes of right-of-ways and the amount of traffic on the adjacent roads synergistically worked to influence wildlife communities. On roads with low traffic, avian species richness increased rapidly with increased right-of-way width, while on roads with high traffic, avian richness increased only slightly with increasing right-of-way widths. We found that wider roadside right-of-ways (preferably across the road from equally wide right-of-ways) with thicker and taller vegetation had the greatest conservation value for birds and small mammals. The features that enhanced the conservation value of right-of-ways in our study area were uncommon. Efforts to create or enhance these features for the benefit of wildlife would likely face numerous obstacles. Nonetheless, from a grassland conservation perspective, working with stakeholders to implement specific strategies to enhance these often neglected areas may be an effective complement to purchasing and restoring conservation lands away from roads. PMID:25794180

  4. Watershed Influences on Residence Time and Oxygen Reduction Rates in an Agricultural Landscape

    NASA Astrophysics Data System (ADS)

    Shope, C. L.; Tesoriero, A. J.

    2015-12-01

    Agricultural use of synthetic fertilizers and animal manure has led to increased crop production, but also elevated nitrogen concentrations in groundwater, resulting in impaired water quality. Groundwater oxygen concentrations are a key indicator of potential biogeochemical processes, which control water/aquifer interactions and contaminant transport. The U.S. Geological Survey's National Water-Quality Assessment Program has a long-history of studying nutrient transport and processing across the United States and the Glacial Aquifer system in particular. A series of groundwater well networks in Eastern Wisconsin is being used to evaluate the distribution of redox reaction rates over a range of scales with a focus on dissolved O2 reduction rates. An analysis of these multi-scale networks elucidates the influence of explanatory variables (i.e.: soil type, land use classification) on reduction rates and redox reactions throughout the Fox-Wolf-Peshtigo watersheds. Multiple tracers including dissolved gasses, tritium, helium, chlorofluorocarbons, sulfur hexafluoride, and carbon-14 were used to estimate groundwater ages (0.8 to 61.2 yr) at over 300 locations. Our results indicate O2 reduction rates along a flowpath study area (1.2 km2) of 0.15 mg O2 L-1 yr-1 (0.12 to 0.18 mg O2 L-1 yr-1) up to 0.41 mg O2 L-1 yr-1 (0.23 to 0.89 mg O2 L-1 yr-1) for a larger scale land use study area (3,300 km2). Preliminary explanatory variables that can be used to describe the variability in reduction rates include soil type (hydrologic group, bulk density) and chemical concentrations (nitrite plus nitrate, silica). The median residence time expected to reach suboxic conditions (≤ 0.4 mg O2 L-1) for the flowpath and the land use study areas was 66 and 25 yr, respectively. These results can be used to elucidate and differentiate the impact of residence time on groundwater quality vulnerability and sustainability in agricultural regions without complex flow models.

  5. Environmental attitudes and drift reduction behavior among commercial pesticide applicators in a U.S. agricultural landscape.

    PubMed

    Reimer, Adam P; Prokopy, Linda S

    2012-12-30

    Pesticide drift is a significant environmental problem in rural regions, and can result in losses to certain non-target crops and livestock, water and air pollution, and threats to human health. While state agencies seek to control the harmful effects of pesticides through licensing and certificate programs, the adoption rates of drift-reducing practices by commercial applicators remain highly variable. In order to effectively target outreach efforts to commercial applicators, managers need to better understand current use patterns and the motivations behind the adoption and non-adoption of preferred practices. Using a web and mail survey, this study explored environmental attitudes, awareness and concern for pesticide drift, and current practice adoption for drift reduction by commercial pesticide applicators in Indiana. Researchers surveyed three distinct applicator types: industrial weed management (utility right-of-way), agriculture, and aerial (which are mostly spraying in an agricultural setting). Overall, applicators exhibited positive environmental attitudes, but low concern for pesticide drift in the geographic areas where they operate. Adoption rates for several drift reduction technologies were high, particularly for equipment and spray modifications such as low-drift spray nozzles (88%) and increased spray droplet size (92%). Applicators were less familiar with specialty equipment (such as band sprayers, 13% adoption rate) and methods for identifying sensitive sites such as bee colonies and organic crops. Among the three groups, industrial weed management applicators had the lowest adoption rates. Applicators were motivated to adopt drift-reduction practices by the desire to be a good neighbor and a desire to be a good land steward. There is potential for use of more innovative, voluntary approaches to raise awareness of sites sensitive to pesticide drift in rural landscapes. PMID:23062271

  6. Evaluating atmospheric CO2 inversions at multiple scales over a highly-inventoried agricultural landscape

    NASA Astrophysics Data System (ADS)

    Schuh, A. E.; Lauvaux, T.; West, T. O.; Uliasz, M.; Mueller, K. L.; Davis, K. J.; Ogle, S. M.

    2011-12-01

    Atmospheric inversions provide a promising method for real-time estimation of carbon flux estimation. Although tantalizing as a tool for policy makers, many uncertainties still surround the techniques used. Historically, data constraints, in particular highly calibrated CO2 data, could always be pointed to as the main bottleneck for future usability. However, an intensive campaign spawned by the NACP, over the highly productive agricultural regions of the Midwestern United States, has shown that the availability of calibrated CO2 data might no longer be the main concern of all atmospheric inversions, at least for particular case studies. Comparisons of results across four different inversion frameworks, operating globally, continentally, and regionally, imply some level of robustness at the regional level of the entire MCI. The results from the continental inversion system imply that estimates of net ecosystem exchange (NEE) at the regional level appear to be more robust to boundary conditions of CO2 at the continental margins than NEE estimates at the continental scale. Nevertheless, significant differences still exist across the inversions at the sub-regional scale, 100km - 200km, as well as across different years (2007 vs 2008). We will explore the reasons for these differences and how the differences relate to variations in transport, boundary condition inflow of CO2, and climatic conditions of 2007 and 2008.

  7. Towards multifunctional agricultural landscapes in Europe: Assessing and governing synergies between food production, biodiversity, and ecosystem services - TALE

    NASA Astrophysics Data System (ADS)

    Volk, Martin; Cord, Anna; Demiguel, Ángel; Holzkämper, Annelie; Kaim, Andrea; Kirchner, Mathias; Lienhoop, Nele; Nieto Romero, Marta; Nitsch, Heike; Rutz, Cordula; Saa, Antonio; Schmid, Erwin; Schönhart, Martin; Schramek, Jörg; Strauch, Michael; Tarquis Alfonso, Ana Maria; van der Zanden, Emma H.; Verburg, Peter; Willaarts, Bárbara; Zarrineh, Nina; Rivas, David; Hagemann, Nina

    2016-04-01

    There is a need to improve our understanding of the synergies between biodiversity, food and energy production and other regulating or cultural ecosystem services (ESS) and the development of technical and policy measures to support these synergies. Procedures to quantify synergies and trade-offs between ESS and biodiversity are considered as promising solutions to close this gap. The BiodivERsA project TALE aims at developing such methodologies in a set of representative European agricultural landscapes in Germany, Switzerland, Austria, The Netherlands and Spain. This will be done by using i) a framework that links process-based, integrated, and statistical models with optimization algorithms, and ii) a set of land use scenarios and land use policies, iii) a systematic stakeholder integration process that allows the incorporation of expert knowledge in all phases of the research project to safeguard that research results are of practical relevance. Moreover, the project not only addresses experts but provides an innovative online learning environment that is accessible also for students and the general public.

  8. Groundwater dynamics in wetland soils control the production and transfer mechanisms of dissolved reactive phosphorus in an agricultural landscape

    NASA Astrophysics Data System (ADS)

    Dupas, Rémi; Gu, Sen; Gruau, Gérard; Gascuel-Odoux, Chantal

    2015-04-01

    Because of its high sorption affinity on soils solid phase, mitigation options to reduce diffuse P transfer usually focus on trapping particulate P forms delivered via surface flowpaths. Therefore, vegetated buffer zones placed between croplands and watercourses have been promoted worldwide, sometimes in wetland areas. To investigate the risk of such P trapping riparian wetlands (RWs) releasing dissolved P to rivers, we monitored molybdate reactive P (MRP) in the free soil solution of two RWs in an intensively farmed catchment. Two main mechanisms causing MRP release were identified in light of the geochemical and hydrological conditions in the RWs, controlled by groundwater dynamics. First, soil rewetting after the dry summer was associated with the presence of a pool of mobile P, limited in size. Its mobilization started under conditions of water saturation caused by groundwater uprise in RW organo-mineral soil horizons. Second, the establishment of anoxic conditions in the end of the winter caused reductive solubilization of Fe oxide-hydroxide, along with release of P. Comparison between sites revealed that the first MRP release occurred only in a RW with P enriched soils, whereas the second was recorded even in a RW with a low soil P status. Seasonal variations in MRP concentrations in the stream were synchronized with those in RW soils. Hence, enriched and/or periodically anoxic RWs can act as a key component of the P transfer continuum in agricultural landscapes by converting particulate P from croplands into MRP released to rivers.

  9. Tall tower landscape scale N2O flux measurements in a Danish agricultural and urban, coastal area

    NASA Astrophysics Data System (ADS)

    Ibrom, Andreas; Lequy, Émeline; Loubet, Benjamin; Pilegaard, Kim; Ambus, Per

    2015-04-01

    eastern coastline of the Roskilde fjord on the Danish island Zealand. The tower is surrounded by the fjord, by agricultural area, forests and, in the South by the urban area of the City of Roskilde. The City of Roskilde operates a waste incinerator and a waste water treatment plant, which drains treated waste water into the fjord. The level of the measured flux values was generally relatively low. Based on the clear definition of the lag time between N2O concentrations and the vertical wind speed, fluxes were measureable over larger periods. The fluxes showed clear directional relationships indicating their large spatial and temporal variability in the landscape. Footprint calculations were performed to attribute source areas to the measured fluxes ...(Kormann and Meixner, 2001; Neftel et al., 2008). The footprint of the flux measurement included areas between 200 m and several kilometres distance from the tower. A preliminary approach was developed to generate monthly maps of N2O fluxes around the tower. Here we present the results from the first seven months of flux measurements. Based on these results we discuss the potential and the limitations of tall tower eddy covariance measurements to estimate maps of N2O fluxes and the integral value of the landscape N2O flux. Acknowledgements: This work was funded by the EU-FP7 InGOS project. We thank Ebba Dellwik (Technical University of Denmark) for providing sonic anemometer data. References: Kormann, R. and Meixner, F.X., 2001. An Analytical Footprint Model For Non-Neutral Stratification. Boundary-Layer Meteorology, 99(2): 207-224. Neftel, A., Spirig, C. and Ammann, C., 2008. Application and test of a simple tool for operational footprint evaluations. Environmental Pollution, 152(3): 644-652.

  10. Fugitive methane emissions from natural, urban, agricultural, and energy-production landscapes of eastern Australia

    NASA Astrophysics Data System (ADS)

    Kelly, Bryce F. J.; Iverach, Charlotte P.; Lowry, Dave; Fisher, Rebecca E.; France, James L.; Nisbet, Euan G.

    2015-04-01

    Modern cavity ringdown spectroscopy systems (CRDS) enable the continuous measurement of methane concentration. This allows for improved quantification of greenhouse gas emissions associated with various natural and human landscapes. We present a subset of over 4000 km of continuous methane surveying along the east coast of Australia, made using a Picarro G2301 CRDS, deployed in a utility vehicle with an air inlet above the roof at 2.2 mAGL. Measurements were made every 5 seconds to a precision of <0.5 ppb for CH4. These surveys were undertaken during dry daytime hours and all measurements were moisture corrected. We compare the concentration of methane in the near surface atmosphere adjacent to open-cut coal mines, unconventional gas developments (coal seam gas; CSG), and leaks detected in cities and country towns. In areas of dryland crops the median methane concentration was 1.78 ppm, while in the irrigation districts located on vertisol soils the concentration was as low as 1.76 ppm, which may indicate that these soils are a sink for methane. In the Hunter Valley, New South Wales, open-cut coal mining district we mapped a continuous 50 km interval where the concentration of methane exceeded 1.80 ppm. The median concentration in this interval was 2.02 ppm. Peak readings were beyond the range of the reliable measurement (in excess of 3.00 ppm). This extended plume is an amalgamation of plumes from 17 major pits 1 to 10 km in length. Adjacent to CSG developments in the Surat Basin, southeast Queensland, only small anomalies were detected near the well-heads. Throughout the vast majority of the gas fields the concentration of methane was below 1.80 ppm. The largest source of fugitive methane associated with CSG was off-gassing methane from the co-produced water holding ponds. At one location the down wind plume had a cross section of approximately 1 km where the concentration of methane was above 1.80 ppm. The median concentration within this section was 1.82 ppm

  11. The role of constructed wetlands in sequestering eroded carbon in an agricultural landscape.

    NASA Astrophysics Data System (ADS)

    Maynard, J. J.; O'Geen, A. T.; Dahlgren, R. A.

    2008-12-01

    The fate of carbon lost by erosion is not well understood in agricultural settings. Recent models suggest that wetlands and other small water bodies may serve as important long-term sinks of eroded carbon. An estimated 2.6 million small (less than 104 m2), artificial water bodies (e.g. water catchment reservoirs, farm ponds, and wetlands) are scattered across the United States. These areas are estimated to receive one third of all eroded materials. Consequently, carbon accumulation in small subaqueous environments may have a significant effect on carbon storage. The conversion of marginal farmland to constructed and restored wetlands is a growing land use in California's Central Valley. Many of these systems receive agricultural runoff as their main water supply, which is rich in suspended sediment and nutrients. This study examined the potential for carbon sequestration in an eight-year-old seasonally saturated constructed wetland that receives tailwater from over 4,000 acres of farmland. The temporal and spatial dynamics of carbon and sediment accumulation were evaluated by employing a spatially explicit sampling design to measure net sedimentation and net above-ground biomass in 2004 and 2005. Additionally, in 2006, sediment cores were collected to the antecedent (time zero) soil layer, which ranged between 2 and 50 cm below the surface. The spatial variability of carbon and sediment accumulation was modeled with geostatistics. Average sediment accumulation rate, nearly doubled from 2004 to 2005, with rates of 5.8 kg m-2 y-1 (range: 0-80 kg m-2 y-1) in 2004 and 11.9 kg m-2 y-1 (range: 0-93 kg m2 y-1) in 2005. Average carbon accumulation rate did not change between years, with rates of 0.290 kg m-2 y-1 in 2004 and 0.294 kg m-2 y-1 in 2005, indicating a change in carbon source between years. Average total carbon content of soils in the contributing watershed is 8 g kg-1, whereas average carbon content of inflowing sediment was 14 g kg-1, resulting in an enrichment

  12. Riparian buffer strips as a multifunctional management tool in agricultural landscapes: introduction.

    PubMed

    Stutter, Marc I; Chardon, Wim J; Kronvang, Brian

    2012-01-01

    Catchment riparian areas are considered key zones to target mitigation measures aimed at interrupting the movement of diffuse substances from agricultural land to surface waters. Hence, unfertilized buffer strips have become a widely studied and implemented "edge of field" mitigation measure assumed to provide an effective physical barrier against nitrogen (N), phosphorus (P), and sediment transfer. To ease the legislative process, these buffers are often narrow mandatory strips along streams and rivers, across different riparian soil water conditions, between bordering land uses of differing pollution burdens, and without prescribed buffer management. It would be easy to criticize such regulation for not providing the opportunity for riparian ecosystems to maximize their provision for a wider range of ecosystem goods and services. The scientific basis for judging the best course of action in designing and placing buffers to enhance their multifunctionality has slowly increased over the last five years. This collection of papers aims to add to this body of knowledge by giving examples of studies related to riparian buffer management and assessment throughout Europe. This introductory paper summarizes discussion sessions and 13 selected papers from a workshop held in Ballater, UK, highlighting research on riparian buffers brought together under the EU COST Action 869 knowledge exchange program. The themes addressed are (i) evidence of catchment- to national-scale effectiveness, (ii) ecological functioning linking terrestrial and aquatic habitats, (iii) modeling tools for assessment of effectiveness and costs, and (iv) process understanding enabling management and manipulation to enhance pollutant retention in buffers. The combined understanding led us to consider four principle key questions to challenge buffer strip research and policy. PMID:22370391

  13. Evaluating atmospheric CO2 inversions at multiple scales over a highly-inventoried agricultural landscape.

    SciTech Connect

    Schuh, Andrew E.; Lauvaux, Thomas; West, Tristram O.; Denning, A.; Davis, Kenneth J.; Miles, Natasha; Richardson, S. J.; Uliasz, Marek; Lokupitiya, Erandathie; Cooley, Dan; Andrews, Arlyn; Ogle, Stephen

    2013-05-01

    An intensive regional research campaign was conducted by the North American Carbon Program (NACP) in 2005 to study the carbon cycle of the highly productive agricultural regions of the Midwestern United States. Forty-_ve di_erent associated projects were spawned across _ve U.S. agencies over the course of nearly a decade involving hundreds of researchers. The primary objective of the project was to investigate the ability of atmospheric inversion techniques to use highly calibrated CO2 mixing ratio data to estimate CO2 exchange over the major croplands of the U.S. Statistics from densely monitored crop production, consisting primarily corn and soybeans, provided the backbone of a well-studied\\bottom up"flux estimate that was used to evaluate the atmospheric inversion results. Three different inversion systems, representing spatial scales varying from high resolution mesoscale, to continental, to global, coupled to different transport models and optimization techniques were compared to the bottom up" inventory estimates. The mean annual CO2-C sink for 2007 from the inversion systems ranged from 120 TgC to 170 TgC, when viewed across a wide variety of inversion setups, with the best" point estimates ranging from 145 TgC to 155 TgC. Inversion-based mean C sink estimates were generally slightly stronger, but statistically indistinguishable,from the inventory estimate whose mean C sink was 135 TgC. The inversion results showed temporal correlations at seasonal lengths while week to week correlations remained low. Comparisons were made between atmospheric transport yields of the two regional inversion systems, which despite having different influence footprints in space and time due to differences in underlying transport models and external forcings, showed similarity when aggregated in space and time.

  14. Satellite surface soil moisture from SMOS and Aquarius: Assessment for applications in agricultural landscapes

    NASA Astrophysics Data System (ADS)

    Champagne, Catherine; Rowlandson, Tracy; Berg, Aaron; Burns, Travis; L'Heureux, Jessika; Tetlock, Erica; Adams, Justin R.; McNairn, Heather; Toth, Brenda; Itenfisu, Daniel

    2016-03-01

    Satellite surface soil moisture has become more widely available in the past five years, with several missions designed specifically for soil moisture measurement now available, including the Soil Moisture and Ocean Salinity (SMOS) mission and the Soil Moisture Active/Passive (SMAP) mission. With a wealth of data now available, the challenge is to understand the skill and limitations of the data so they can be used routinely to support monitoring applications and to better understand environmental change. This paper examined two satellite surface soil moisture data sets from the SMOS and Aquarius missions against in situ networks in largely agricultural regions of Canada. The data from both sensors was compared to ground measurements on both an absolute and relative basis. Overall, the root mean squared errors for SMOS were less than 0.10 m3 m-3 at most sites, and less where the in situ soil moisture was measured at multiple sites within the radiometer footprint (sites in Saskatchewan, Manitoba and Ontario). At many sites, SMOS overestimates soil moisture shortly after rainfall events compared to the in situ data; however this was not consistent for each site and each time period. SMOS was found to underestimate drying events compared to the in situ data, however this observation was not consistent from site to site. The Aquarius soil moisture data showed higher root mean squared errors in areas where there were more frequent wetting and drying cycles. Overall, both data sets, and SMOS in particular, showed a stable and consistent pattern of capturing surface soil moisture over time.

  15. Grassland agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agriculture in grassland environments is facing multiple stresses from: shifting demographics, declining and fragmented agricultural landscapes, declining environmental quality, variable and changing climate, volatile and increasing energy costs, marginal economic returns, and globalization. Degrad...

  16. Assessing the mitigation potential of agricultural systems by optimization of the agricultural management: A modeling study on 8 agricultural observation sites across Europe with the process based model LandscapeDNDC

    NASA Astrophysics Data System (ADS)

    Molina Herrera, Saul; Haas, Edwin; Klatt, Steffen; Kraus, David; Kiese, Ralf; Butterbach-Bahl, Klaus

    2014-05-01

    The use of mineral nitrogen (N) fertilizers increase crop yields but cause the biggest anthropogenic source of nitrous oxide (N2O) emissions and strongly contribute to surface water eutrophication (e.g. nitrate leaching). The necessity to identify affordable strategies that improve crop production while improving ecosystem services are in continuous debate between policy decision makers and farmers. In this line, a lack commitment from farmers to enforce laws might result in the reduction of benefits. For this reason, farmers should aim to increase crop production and to reduce environmental harm by the adoption of precision climate smart agriculture tools applied to management practices for instance. In this study we present optimized strategies for 8 sites (agricultural and grassland ecosystems) with long term field observation across Europe to show the mitigation potential to reduce reactive nitrogen losses under the constrain of keeping yields at observed levels. LandscapeDNDC simulations of crop yields and associated nitrogen losses (N2O emissions and NO3 leaching) were evaluated against long term field measurements. The sites presented different management regimes including the main commodity crops (maize, wheat, barley, rape seeds, etc) and fertilization amendments (synthetic and organic fertilizers) in Europe. The simulations reproduced the observed yields, captured N2O emissions and NO3 leaching losses with high statistical presicion (r2), acurrency (ME) and agreement (RMSPEn). The mitigation potentials to reduce N losses while keeping yields at observed levels for all 8 sites were assesed by Monte Carlo optimizations of the individual underlying multi year agricultural management options (timings of planting and harvest, fertilization & manure applications and rates, residues management). In this study we present for all 8 agricultural observations sites their individual mitigation potentials to reduce N losses for multi year rotations. The conclusions

  17. Changes in water budgets and sediment yields from a hypothetical agricultural field as a function of landscape and management characteristics--A unit field modeling approach

    USGS Publications Warehouse

    Roth, Jason L.; Capel, Paul D.

    2012-01-01

    Crop agriculture occupies 13 percent of the conterminous United States. Agricultural management practices, such as crop and tillage types, affect the hydrologic flow paths through the landscape. Some agricultural practices, such as drainage and irrigation, create entirely new hydrologic flow paths upon the landscapes where they are implemented. These hydrologic changes can affect the magnitude and partitioning of water budgets and sediment erosion. Given the wide degree of variability amongst agricultural settings, changes in the magnitudes of hydrologic flow paths and sediment erosion induced by agricultural management practices commonly are difficult to characterize, quantify, and compare using only field observations. The Water Erosion Prediction Project (WEPP) model was used to simulate two landscape characteristics (slope and soil texture) and three agricultural management practices (land cover/crop type, tillage type, and selected agricultural land management practices) to evaluate their effects on the water budgets of and sediment yield from agricultural lands. An array of sixty-eight 60-year simulations were run, each representing a distinct natural or agricultural scenario with various slopes, soil textures, crop or land cover types, tillage types, and select agricultural management practices on an isolated 16.2-hectare field. Simulations were made to represent two common agricultural climate regimes: arid with sprinkler irrigation and humid. These climate regimes were constructed with actual climate and irrigation data. The results of these simulations demonstrate the magnitudes of potential changes in water budgets and sediment yields from lands as a result of landscape characteristics and agricultural practices adopted on them. These simulations showed that variations in landscape characteristics, such as slope and soil type, had appreciable effects on water budgets and sediment yields. As slopes increased, sediment yields increased in both the arid and

  18. Conservation of Pollinators in Traditional Agricultural Landscapes – New Challenges in Transylvania (Romania) Posed by EU Accession and Recommendations for Future Research

    PubMed Central

    Kovács-Hostyánszki, Anikó; Földesi, Rita; Mózes, Edina; Szirák, Ádám; Fischer, Joern; Hanspach, Jan; Báldi, András

    2016-01-01

    Farmland biodiversity is strongly declining in most of Western Europe, but still survives in traditional low intensity agricultural landscapes in Central and Eastern Europe. Accession to the EU however intensifies agriculture, which leads to the vanishing of traditional farming. Our aim was to describe the pollinator assemblages of the last remnants of these landscapes, thus set the baseline of sustainable farming for pollination, and to highlight potential measures of conservation. In these traditional farmlands in the Transylvanian Basin, Romania (EU accession in 2007), we studied the major pollinator groups—wild bees, hoverflies and butterflies. Landscape scale effects of semi-natural habitats, land cover diversity, the effects of heterogeneity and woody vegetation cover and on-site flower resources were tested on pollinator communities in traditionally managed arable fields and grasslands. Our results showed: (i) semi-natural habitats at the landscape scale have a positive effect on most pollinators, especially in the case of low heterogeneity of the direct vicinity of the studied sites; (ii) both arable fields and grasslands hold abundant flower resources, thus both land use types are important in sustaining pollinator communities; (iii) thus, pollinator conservation can rely even on arable fields under traditional management regime. This has an indirect message that the tiny flower margins around large intensive fields in west Europe can be insufficient conservation measures to restore pollinator communities at the landscape scale, as this is still far the baseline of necessary flower resources. This hypothesis needs further study, which includes more traditional landscapes providing baseline, and exploration of other factors behind the lower than baseline level biodiversity values of fields under agri-environmental schemes (AES). PMID:27285118

  19. Conservation of Pollinators in Traditional Agricultural Landscapes - New Challenges in Transylvania (Romania) Posed by EU Accession and Recommendations for Future Research.

    PubMed

    Kovács-Hostyánszki, Anikó; Földesi, Rita; Mózes, Edina; Szirák, Ádám; Fischer, Joern; Hanspach, Jan; Báldi, András

    2016-01-01

    Farmland biodiversity is strongly declining in most of Western Europe, but still survives in traditional low intensity agricultural landscapes in Central and Eastern Europe. Accession to the EU however intensifies agriculture, which leads to the vanishing of traditional farming. Our aim was to describe the pollinator assemblages of the last remnants of these landscapes, thus set the baseline of sustainable farming for pollination, and to highlight potential measures of conservation. In these traditional farmlands in the Transylvanian Basin, Romania (EU accession in 2007), we studied the major pollinator groups-wild bees, hoverflies and butterflies. Landscape scale effects of semi-natural habitats, land cover diversity, the effects of heterogeneity and woody vegetation cover and on-site flower resources were tested on pollinator communities in traditionally managed arable fields and grasslands. Our results showed: (i) semi-natural habitats at the landscape scale have a positive effect on most pollinators, especially in the case of low heterogeneity of the direct vicinity of the studied sites; (ii) both arable fields and grasslands hold abundant flower resources, thus both land use types are important in sustaining pollinator communities; (iii) thus, pollinator conservation can rely even on arable fields under traditional management regime. This has an indirect message that the tiny flower margins around large intensive fields in west Europe can be insufficient conservation measures to restore pollinator communities at the landscape scale, as this is still far the baseline of necessary flower resources. This hypothesis needs further study, which includes more traditional landscapes providing baseline, and exploration of other factors behind the lower than baseline level biodiversity values of fields under agri-environmental schemes (AES). PMID:27285118

  20. Structure and composition of altered riparian forests in an agricultural Amazonian landscape.

    PubMed

    Nagy, R Chelsea; Porder, Stephen; Neill, Christopher; Brando, Paulo; Quintino, Raimundo Mota; do Nascimento, Sebastiâo Aviz

    2015-09-01

    Deforestation and fragmentation influence the microclimate, vegetation structure, and composition of remaining patches of tropical forest. In the southern Amazon, at the frontier of cropland expansion, forests are converted and fragmented in a pattern that leaves standing riparian forests whose dimensions are mandated by the Brazilian National Forest Code. These altered riparian forests share many characteristics of well-studied upland forest fragments, but differ because they remain connected to larger areas of forest downstream, and because they may experience wetter soil conditions because reduction of forest cover in the surrounding watershed raises groundwater levels and increases stream runoff. We compared forest regeneration, structure, composition, and diversity in four areas of intact riparian forest and four areas each of narrow, medium, and wide altered riparian forests that have been surrounded by agriculture since the early 1980s. We found that seedling abundance was reduced by as much as 64% and sapling abundance was reduced by as much as 67% in altered compared to intact riparian forests. The most pronounced differences between altered and intact forest occurred near forest edges and within the narrowest sections of altered riparian forests. Woody plant species composition differed and diversity was reduced in altered forests compared to intact riparian forests. However, despite being fragmented for several decades, large woody plant biomass and carbon storage, the number of live or dead large woody plants, mortality rates, and the size distribution of woody plants did not differ significantly between altered and intact riparian forests. Thus, even in these relatively narrow forests with high edge: area ratios, we saw no evidence of the increases in mortality and declines in biomass that have been found in other tropical forest fragment studies. However, because of the changes in both species community and reduced regeneration, it is unclear how long

  1. The relative importance of fertilization and soil erosion on C-dynamics in agricultural landscapes of NE Germany

    NASA Astrophysics Data System (ADS)

    Pohl, Madlen; Hoffmann, Mathias; Hagemann, Ulrike; Jurisch, Nicole; Remus, Rainer; Sommer, Michael; Augustin, Jürgen

    2016-04-01

    The hummocky ground moraine landscape of north-east Germany is characterized by distinct small-scale soil heterogeneity on the one hand, and intensive energy crop cultivation on the other. Both factors are assumed to significantly influence gaseous C exchange, and thus driving the dynamics of soil organic carbon stocks in terrestrial, agricultural ecosystems. However, it is not yet clear to which extent fertilization and soil erosional status influence soil C dynamics and whether one of these factors is more relevant than the other. We present seasonal and dynamic soil C balances of biogas maize for the growing season 2011, recorded at different sites located within the CarboZALF experimental area. The sites differ regarding soils (non-eroded Albic Luvisols (Cutanic), extremely eroded Calcaric Regosol and depositional Endogleyic Colluvic Regosol,) and applied fertilizer (100% mineral N fertilizer, 50% mineral and 50% N organic fertilizer, 100% organic N fertilizer). Fertilization treatments were established on the Albic Luvisol (Cutanic). Net-CO2-exchange (NEE) and ecosystem respiration (Reco) were measured every four weeks using a dynamic flow-through non-steady-state closed manual chamber system. Gap filling was performed based on empirical temperature and PAR dependency functions to derive daily NEE values. At the same time, daily above-ground biomass production (NPP) was estimated based on biomass samples and final harvest, using a sigmoidal growth function. In a next step, dynamic soil C balances were generated as the balance of daily NEE and NPP considering the initial C input due to N fertilizers. The resulted seasonal soil C balances varied from strong C losses at the Endogleyic Colluvic Regosol (602 g C m-2) to C gains at the Calcaric Regosol (-132 g C m-2). In general, soils exerted a stronger impact on seasonal and dynamic C balances compared to differences in applied N fertilizer. There are indications that inter-annual variations in climate conditions

  2. Landscape factors influencing the spatial distribution and abundance of mosquito vector Culex quinquefasciatus (Diptera: Culicidae) in a mixed residential-agricultural community in Hawai'i

    USGS Publications Warehouse

    Reiter, M.E.; Lapointe, D.A.

    2007-01-01

    Mosquito-borne avian diseases, principally avian malaria (Plasmodium relictum Grassi and Feletti) and avian pox (Avipoxvirus sp.) have been implicated as the key limiting factor associated with recent declines of endemic avifauna in the Hawaiian Island archipelago. We present data on the relative abundance, infection status, and spatial distribution of the primary mosquito vector Culex quinquefasciatus Say (Diptera: Culicidae) across a mixed, residential-agricultural community adjacent to Hawai'i Volcanoes National Park on Hawai'i Island. We modeled the effect of agriculture and forest fragmentation in determining relative abundance of adult Cx. quinquefasciatus in Volcano Village, and we implement our statistical model in a geographic information system to generate a probability of mosquito capture prediction surface for the study area. Our model was based on biweekly captures of adult mosquitoes from 20 locations within Volcano Village from October 2001 to April 2003. We used mixed effects logistic regression to model the probability of capturing a mosquito, and we developed a set of 17 competing models a priori to specifically evaluate the effect of agriculture and fragmentation (i.e., residential landscapes) at two spatial scales. In total, 2,126 mosquitoes were captured in CO 2-baited traps with an average probability of 0.27 (SE = 0.10) of capturing one or more mosquitoes per trap night. Twelve percent of mosquitoes captured were infected with P. relictum. Our data indicate that agricultural lands and forest fragmentation significantly increase the probability of mosquito capture. The prediction surface identified areas along the Hawai'i Volcanoes National Park boundary that may have high relative abundance of the vector. Our data document the potential of avian malaria transmission in residential-agricultural landscapes and support the need for vector management that extends beyond reserve boundaries and considers a reserve's spatial position in a highly

  3. Caesium-137 root uptake by agricultural and wild crops in post-Chernobyl landscape: the possibilities for phytoremediation?

    NASA Astrophysics Data System (ADS)

    Paramonova, Tatiana; Shamshurina, Eugenia; Komissarova, Olga; Belyaev, Vladimir

    2015-04-01

    In spite of long term period after Chernobyl fallout (≈25 years after the accident) the level of Cs-137 in soils of contaminated landscapes remains several times more than radiation safety standard (= 37 kBq/m2). In particular, within the area of Plavsk radioactive hot spot (Tula region, Russia) current Cs-137 activities in soil are 460-500 Bq/kg (170-200 kBq/m2) on watershed, 580-680 Bq/kg (200-220 kBq/m2) in arable lower parts of slopes and 620-710 Bq/kg (210-280 kBq/m2) in untilled foots of slopes and river floodplains. To estimate the process of Cs-137 root uptake and incorporation of the radionuclide in plant tissues 6 agricultural crops of typical field rotation (spring barley, maize, summer rape, galega, potatoes, amaranth) as well as natural ecosystems of dry and wet meadows were selected for the detailed study. Total bioproductivity of agricultural crops varies between 1.7-3.9 kg/m2, natural grass ecosystems - 1.9-2.2 g/m2, and is obviously unaffected by radioactive land contamination. At the same time Cs-137 activity in total biomass slightly increases with Cs-137 activity in soil (correlation coefficient r=0.45) and with total biomass (correlation coefficient r=0.51) in the row: rape (5 Bq/kg) < amaranth, galega (17-19 Bq/kg) < barley, potatoes (31-37 Bq/kg) < maize (58 Bq/kg) < dry meadow (73 Bq/kg) < wet meadow (120 Bq/kg). Commonly, Cs-137 activity in vegetation of natural ecosystems with predominance of perennial grasses is significantly higher than in agrosystems with annual crops. But a substantial portion of Cs-137 in meadow vegetation is associated with belowground biomass, where the radionuclide's activity is 3-5 times greater than in the aboveground part. The distribution of Cs-137 activities between above- and belowground parts of agricultural crops greatly varies depending on the biological characteristics of plants: barley and maize (Gramíneae family) are also characterized by elevated Cs-137 concentrations in belowground parts (12

  4. Simulating Sustainable P Management Practices in Tile-Drained Landscapes of Central Ohio Using the Agricultural Policy Environmental Extender (APEX)

    NASA Astrophysics Data System (ADS)

    Ford, W. I., III; King, K.; Williams, M.

    2014-12-01

    Despite extensive application of conservation practices to minimize sediment P delivery to streams, hypoxic conditions and harmful algal blooms persist in receiving water bodies. Tile-drainage networks are a focal point for reducing soluble P in the food-producing Midwestern United States in that they promote higher connectivity between upland soils and stream channels which decreases soil contact time, and biogeochemical alterations. A critical next step to reduce the environmental impact and maintain sustainable agriculture is to implement best management practices (BMPs) under a holistic framework that considers adverse effects to water resources and crop production, while maintaining economic feasibility. The objective of this study was to apply a robust numerical model, the Agricultural Policy Environmental Extender (APEX), in a tile-drained landscape in Central Ohio in order to evaluate the effectiveness of a suite of BMPs on soluble and particulate P delivery to stream channels. The model was applied and evaluated at two adjacent edge-of-field sites with similar soil, topographic and management characteristics (except for tillage and tile installation on the south field in 2012, preceded by more than 20 years of no-till operations). Three years of daily discharge, total suspended solids, soluble P, soluble N (NO3 and NH4), total P, total N, and crop yields were utilized to verify the model performance. Prevalent BMPs simulated within the modeling framework included drainage water management, tillage and crop rotations, the 4Rs framework (right fertilizer source, rate, time, and placement), and bioreactors. Results of the study quantify the ability of the numerical model to simulate hydrology and P transport for surface runoff and subsurface tile drainage and highlight modifications that improve model performance. Further, results highlight BMPs that effectively reduce P loads to streams while maintaining crop yields, which can later be used to inform BMPs

  5. Agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agriculture within the United States is varied and produces a large value ($200 billion in 2002) of production across a wide range of plant and animal production systems. Because of this diversity, changes in climate will likely impact agriculture throughout the United States. Climate affects crop, ...

  6. Implementing automatic LiDAR and supervised mapping methodologies to quantify agricultural terraced landforms at landscape scale: the case of Veneto Region

    NASA Astrophysics Data System (ADS)

    Eugenio Pappalardo, Salvatore; Ferrarese, Francesco; Tarolli, Paolo; Varotto, Mauro

    2016-04-01

    Traditional agricultural terraced landscapes presently embody an important cultural value to be deeply investigated, both for their role in local heritage and cultural economy and for their potential geo-hydrological hazard due to abandonment and degradation. Moreover, traditional terraced landscapes are usually based on non-intensive agro-systems and may enhance some important ecosystems services such as agro-biodiversity conservation and cultural services. Due to their unplanned genesis, mapping, quantifying and classifying agricultural terraces at regional scale is often critical as far as they are usually set up on geomorphologically and historically complex landscapes. Hence, traditional mapping methods are generally based on scientific literature and local documentation, historical and cadastral sources, technical cartography and aerial images visual interpretation or, finally, field surveys. By this, limitations and uncertainty in mapping at regional scale are basically related to forest cover and lack in thematic cartography. The Veneto Region (NE of Italy) presents a wide heterogeneity of agricultural terraced landscapes, mainly distributed within the hilly and Prealps areas. Previous studies performed by traditional mapping method quantified 2,688 ha of terraced areas, showing the higher values within the Prealps of Lessinia (1,013 ha, within the Province of Verona) and in the Brenta Valley (421 ha, within the Province of Vicenza); however, terraced features of these case studies show relevant differences in terms of fragmentation and intensity of terraces, highlighting dissimilar degrees of clusterization: 1.7 ha on one hand (Province of Verona) and 1.2 ha per terraced area (Province of Vicenza) on the other one. The aim of this paper is to implement and to compare automatic methodologies with traditional survey methodologies to map and assess agricultural terraces in two representative areas of the Veneto Region. Testing different Remote Sensing

  7. Landscape Effects of a Non-Native Grass Facilitate Source Populations of a Native Generalist Bug, Stenotus rubrovittatus, in a Heterogeneous Agricultural Landscape

    PubMed Central

    Yoshioka, A.; Takada, M. B.; Washitani, I.

    2014-01-01

    Non-native plant species can provide native generalist insects, including pests, with novel food and habitats. It is hypothesized that local and landscape-level abundances of non-native plants can affect the population size of generalist insects, although generalists are assumed to be less sensitive to habitat connectivity than specialists. In a heterogeneous landscape in Japan, the relationship between the density of a native pest of rice (Stenotus rubrovittatus (Matsumura) (Heteroptera: Miridae)) and the abundance of Italian ryegrass (Lolium multiflorum Lam. (Poales: Poaceae)), a non-native meadow grass known to facilitate S. rubrovittatus, was analyzed. Statistical analyses of data on bug density, vegetation, and the spatial distribution of fallow fields and meadows dominated by Italian ryegrass, obtained by field surveys, demonstrated that local and landscape-level abundances of Italian ryegrass (the unmowed meadow areas within a few hundred meters of a sampling plot) positively affected bug density before its immigration into rice fields. Our findings suggest that a generalist herbivorous insect that prefers non-native plants responds to spatial availability and connectivity of plant species patches at the metapopulation level. Fragmentation by selective mowing that decreases the total area of source populations and increases the isolation among them would be an effective and environmentally-friendly pest management method. PMID:25205015

  8. Predicted effect of landscape position on wildlife habitat value of Conservation Reserve Enhancement Program wetlands in a tile-drained agricultural region

    USGS Publications Warehouse

    Otis, David L.; Crumpton, William R.; Green, David; Loan-Wilsey, Anna; Cooper, Tom; Johnson, Rex R.

    2013-01-01

    Justification for investment in restored or constructed wetland projects are often based on presumed net increases in ecosystem services. However, quantitative assessment of performance metrics is often difficult and restricted to a single objective. More comprehensive performance assessments could help inform decision-makers about trade-offs in services provided by alternative restoration program design attributes. The primary goal of the Iowa Conservation Reserve Enhancement Program is to establish wetlands that efficiently remove nitrates from tile-drained agricultural landscapes. A secondary objective is provision of wildlife habitat. We used existing wildlife habitat models to compare relative net change in potential wildlife habitat value for four alternative landscape positions of wetlands within the watershed. Predicted species richness and habitat value for birds, mammals, amphibians, and reptiles generally increased as the wetland position moved lower in the watershed. However, predicted average net increase between pre- and post-project value was dependent on taxonomic group. The increased average wetland area and changes in surrounding upland habitat composition among landscape positions were responsible for these differences. Net change in predicted densities of several grassland bird species at the four landscape positions was variable and species-dependent. Predicted waterfowl breeding activity was greater for lower drainage position wetlands. Although our models are simplistic and provide only a predictive index of potential habitat value, we believe such assessment exercises can provide a tool for coarse-level comparisons of alternative proposed project attributes and a basis for constructing informed hypotheses in auxiliary empirical field studies.

  9. Digital Mapping of Soil Salinity and Crop Yield across a Coastal Agricultural Landscape Using Repeated Electromagnetic Induction (EMI) Surveys

    PubMed Central

    Yao, Rongjiang; Yang, Jingsong; Wu, Danhua; Xie, Wenping; Gao, Peng; Jin, Wenhui

    2016-01-01

    Reliable and real-time information on soil and crop properties is important for the development of management practices in accordance with the requirements of a specific soil and crop within individual field units. This is particularly the case in salt-affected agricultural landscape where managing the spatial variability of soil salinity is essential to minimize salinization and maximize crop output. The primary objectives were to use linear mixed-effects model for soil salinity and crop yield calibration with horizontal and vertical electromagnetic induction (EMI) measurements as ancillary data, to characterize the spatial distribution of soil salinity and crop yield and to verify the accuracy of spatial estimation. Horizontal and vertical EMI (type EM38) measurements at 252 locations were made during each survey, and root zone soil samples and crop samples at 64 sampling sites were collected. This work was periodically conducted on eight dates from June 2012 to May 2013 in a coastal salt-affected mud farmland. Multiple linear regression (MLR) and restricted maximum likelihood (REML) were applied to calibrate root zone soil salinity (ECe) and crop annual output (CAO) using ancillary data, and spatial distribution of soil ECe and CAO was generated using digital soil mapping (DSM) and the precision of spatial estimation was examined using the collected meteorological and groundwater data. Results indicated that a reduced model with EMh as a predictor was satisfactory for root zone ECe calibration, whereas a full model with both EMh and EMv as predictors met the requirement of CAO calibration. The obtained distribution maps of ECe showed consistency with those of EMI measurements at the corresponding time, and the spatial distribution of CAO generated from ancillary data showed agreement with that derived from raw crop data. Statistics of jackknifing procedure confirmed that the spatial estimation of ECe and CAO exhibited reliability and high accuracy. A general

  10. Digital Mapping of Soil Salinity and Crop Yield across a Coastal Agricultural Landscape Using Repeated Electromagnetic Induction (EMI) Surveys.

    PubMed

    Yao, Rongjiang; Yang, Jingsong; Wu, Danhua; Xie, Wenping; Gao, Peng; Jin, Wenhui

    2016-01-01

    Reliable and real-time information on soil and crop properties is important for the development of management practices in accordance with the requirements of a specific soil and crop within individual field units. This is particularly the case in salt-affected agricultural landscape where managing the spatial variability of soil salinity is essential to minimize salinization and maximize crop output. The primary objectives were to use linear mixed-effects model for soil salinity and crop yield calibration with horizontal and vertical electromagnetic induction (EMI) measurements as ancillary data, to characterize the spatial distribution of soil salinity and crop yield and to verify the accuracy of spatial estimation. Horizontal and vertical EMI (type EM38) measurements at 252 locations were made during each survey, and root zone soil samples and crop samples at 64 sampling sites were collected. This work was periodically conducted on eight dates from June 2012 to May 2013 in a coastal salt-affected mud farmland. Multiple linear regression (MLR) and restricted maximum likelihood (REML) were applied to calibrate root zone soil salinity (ECe) and crop annual output (CAO) using ancillary data, and spatial distribution of soil ECe and CAO was generated using digital soil mapping (DSM) and the precision of spatial estimation was examined using the collected meteorological and groundwater data. Results indicated that a reduced model with EMh as a predictor was satisfactory for root zone ECe calibration, whereas a full model with both EMh and EMv as predictors met the requirement of CAO calibration. The obtained distribution maps of ECe showed consistency with those of EMI measurements at the corresponding time, and the spatial distribution of CAO generated from ancillary data showed agreement with that derived from raw crop data. Statistics of jackknifing procedure confirmed that the spatial estimation of ECe and CAO exhibited reliability and high accuracy. A general